10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2022

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                      to                     

Commission file number 0-32405 

SEAGEN INC.

(Exact name of registrant as specified in its charter) 

Delaware	91-1874389
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

21823 30th Drive SE

Bothell, Washington 98021

(Address of principal executive offices, including zip code)

(Registrant’s telephone number, including area code): (425) 527-4000

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, par value $0.001	SGEN	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ☒    No  ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes  ☒    No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. 

Large accelerated filer	☒	Accelerated filer	☐
Non-accelerated filer	☐	Smaller reporting company	☐
Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ☐ No  ☒

As of April 25, 2022, there were 184,075,643 shares of the registrant’s common stock outstanding.

Seagen Inc.

Quarterly Report on Form 10-Q

For the Quarter Ended March 31, 2022

INDEX

		Page
PART I. FINANCIAL INFORMATION (Unaudited)
Item 1.	Condensed Consolidated Financial Statements	3
	Condensed Consolidated Balance Sheets	3
	Condensed Consolidated Statements of Comprehensive Loss	4
	Condensed Consolidated Statements of Stockholders' Equity	5
	Condensed Consolidated Statements of Cash Flows	6
	Notes to Condensed Consolidated Financial Statements	7
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	15
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	33
Item 4.	Controls and Procedures	34
PART II. OTHER INFORMATION
Item 1.	Legal Proceedings	35
Item 1A.	Risk Factors	35
Item 6.	Exhibits	64
SIGNATURE		66

no

2

PART I. FINANCIAL INFORMATION

Item 1.    Condensed Consolidated Financial Statements

Seagen Inc.

Condensed Consolidated Balance Sheets

(Unaudited)

(In thousands, except par value)

	March 31, 2022		December 31, 2021
Assets
Current assets:
Cash and cash equivalents	$	260,996	$	424,834
Short-term investments	1,690,097		1,735,202
Accounts receivable, net	401,009		389,256
Inventories	275,747		200,663
Prepaid expenses and other current assets	143,406		119,239
Total current assets	2,771,255		2,869,194
Property and equipment, net	214,379		210,073
Operating lease right-of-use assets	54,937		57,889
Intangible assets, net	254,902		260,593
Goodwill	274,671		274,671
Other non-current assets	46,549		47,184
Total assets	$	3,616,693	$	3,719,604
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable	$	87,228	$	114,824
Accrued liabilities and other	444,066		454,030
Total current liabilities	531,294		568,854
Long-term liabilities:
Operating lease liabilities, long-term	53,552		56,665
Other long-term liabilities	33,380		28,946
Total long-term liabilities	86,932		85,611
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000 shares authorized; none issued	—		—
Common stock, $0.001 par value, 250,000 shares authorized; 183,892 shares issued and outstanding at March 31, 2022 and 183,381 shares issued and outstanding at December 31, 2021	184		183
Additional paid-in capital	4,678,392		4,607,816
Accumulated other comprehensive income	424		1,179
Accumulated deficit	(1,680,533)		(1,544,039)
Total stockholders’ equity	2,998,467		3,065,139
Total liabilities and stockholders’ equity	$	3,616,693	$	3,719,604

The accompanying notes are an integral part of these condensed consolidated financial statements.

3

Seagen Inc.

Condensed Consolidated Statements of Comprehensive Loss

(Unaudited)

(In thousands, except per share amounts)

	Three Months Ended March 31,
	2022		2021
Revenues:
Net product sales	$	383,086	$	302,588
Royalty revenues	28,181		27,219
Collaboration and license agreement revenues	15,193		2,176
Total revenues	426,460		331,983
Costs and expenses:
Cost of sales	87,626		64,135
Research and development	297,659		230,426
Selling, general and administrative	174,225		159,842
Total costs and expenses	559,510		454,403
Loss from operations	(133,050)		(122,420)
Investment and other (loss) income , net	(2,190)		1,000
Loss before income taxes	(135,240)		(121,420)
Provision for income taxes	1,254		—
Net loss	$	(136,494)	$	(121,420)
Net loss per share - basic and diluted	$	(0.74)	$	(0.67)
Shares used in computation of per share amounts - basic and diluted	183,647		181,150
Comprehensive loss:
Net loss	$	(136,494)	$	(121,420)
Other comprehensive loss:
Unrealized (loss) gain on securities available-for-sale, net of tax	(861)		166
Foreign currency translation gain (loss)	106		(237)
Total other comprehensive loss	(755)		(71)
Comprehensive loss	$	(137,249)	$	(121,491)

The accompanying notes are an integral part of these condensed consolidated financial statements.

4

Seagen Inc.

Condensed Consolidated Statements of Stockholders' Equity

(Unaudited)

(In thousands)

	Common stock
	Shares	Amount		Additional paid-in capital		Accumulated other comprehensive income		Accumulated deficit		Total stockholders' equity
Balances as of December 31, 2020	180,902	$	181	$	4,356,922	$	565	$	(869,568)	$	3,488,100
Net loss	—	—		—		—		(121,420)		(121,420)
Other comprehensive loss	—	—		—		(71)		—		(71)
Issuance of common stock for stock option exercises and employee stock purchase plan	341	—		19,791		—		—		19,791
Restricted stock vested during the period, net	80	—		—		—		—		—
Share-based compensation	—	—		38,224		—		—		38,224
Balances as of March 31, 2021	181,323	181		4,414,937		494		(990,988)		3,424,624
Balances as of December 31, 2021	183,381	$	183	$	4,607,816	$	1,179	$	(1,544,039)	$	3,065,139
Net loss	—	—		—		—		(136,494)		(136,494)
Other comprehensive loss	—	—		—		(755)		—		(755)
Issuance of common stock for stock option exercises and employee stock purchase plan	463	1		26,663		—		—		26,664
Restricted stock vested during the period, net	48	—		—		—		—		—
Share-based compensation	—	—		43,913		—		—		43,913
Balances as of March 31, 2022	183,892	$	184	$	4,678,392	$	424	$	(1,680,533)	$	2,998,467

The accompanying notes are an integral part of these condensed consolidated financial statements.

5

Seagen Inc.

Condensed Consolidated Statements of Cash Flows

(Unaudited)

(In thousands)

	Three Months Ended March 31,
	2022		2021
Operating activities:
Net loss	$	(136,494)	$	(121,420)
Adjustments to reconcile net loss to net cash used by operating activities
Share-based compensation	43,913		38,224
Depreciation	11,402		9,583
Amortization of intangible assets	5,691		5,694
Amortization of right-of-use assets	2,952		3,356
Amortization of premiums, accretion of discounts, and (gains) losses on debt securities	184		6,482
Losses (gains) on equity securities	2,779		(259)
Deferred income taxes	155		—
Changes in operating assets and liabilities
Accounts receivable, net	(11,753)		(10,840)
Inventories	(75,084)		(30,455)
Prepaid expenses and other assets	(24,523)		(27,763)
Lease liability	(5,158)		(4,239)
Other liabilities	(30,876)		6,311
Net cash used by operating activities	(216,812)		(125,326)
Investing activities:
Purchases of securities	(655,940)		(703,200)
Proceeds from maturities of securities	700,000		632,000
Purchases of property and equipment	(17,397)		(7,515)
Net cash provided (used) by investing activities	26,663		(78,715)
Financing activities:
Proceeds from exercise of stock options and employee stock purchase plan	26,664		19,791
Net cash provided by financing activities	26,664		19,791
Effect of exchange rate changes on cash and cash equivalents	(353)		(462)
Net decrease in cash and cash equivalents	(163,838)		(184,712)
Cash and cash equivalents at beginning of period	424,834		558,424
Cash and cash equivalents at end of period	$	260,996	$	373,712

The accompanying notes are an integral part of these condensed consolidated financial statements.

6

Seagen Inc.

Notes to Condensed Consolidated Financial Statements

(Unaudited)

1. Summary of significant accounting policies

Basis of presentation

The accompanying unaudited condensed consolidated financial statements reflect the accounts of Seagen Inc. and its wholly-owned subsidiaries (collectively “Seagen,” “we,” “our,” or “us”). All intercompany transactions and balances have been eliminated. Management has determined that we operate in one segment: the development and sale of pharmaceutical products on our own behalf or in collaboration with others. Substantially all of our assets and revenues are related to operations in the U.S.; however, we have multiple subsidiaries in foreign jurisdictions, including several subsidiaries in Europe.

The condensed consolidated balance sheet data as of December 31, 2021 were derived from audited financial statements not included in this quarterly report on Form 10-Q. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission, or SEC, and generally accepted accounting principles in the United States of America, or GAAP, for unaudited condensed consolidated financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments that, in the opinion of management, are necessary for a fair statement of our financial position and results of our operations as of and for the periods presented.

These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2021, as filed with the SEC.

The preparation of financial statements in accordance with GAAP requires us to make estimates, assumptions, and judgments that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates. The results of our operations for the three month period ended March 31, 2022 are not necessarily indicative of the results to be expected for the full year or any other interim period.

Non-cash activities

We had $8.2 million and $9.9 million of accrued capital expenditures as of March 31, 2022 and December 31, 2021, respectively. Accrued capital expenditures are treated as a non-cash investing activity and, accordingly, have not been included in the condensed consolidated statement of cash flows until such amounts have been paid in cash.

Investments

We hold certain equity securities which are reported at estimated fair value based on quoted market prices. Changes in the fair value of equity securities are recorded in income or loss. The cost of equity securities for purposes of computing gains and losses is based on the specific identification method.

We invest our available cash primarily in debt securities. These debt securities are classified as available-for-sale, which are reported at estimated fair value with unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains, realized losses and declines in the value of debt securities judged to be other-than-temporary are included in investment and other income (loss), net. The cost of debt securities for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Amortization of premiums and accretion of discounts on debt securities are included in investment and other income (loss), net. Interest and dividends earned are included in investment and other income (loss), net. Accrued interest receivable as of March 31, 2022 and December 31, 2021, were $0.6 million and $0.4 million, respectively, and were included in prepaid expenses and other current assets. We classify investments in debt securities maturing within one year of the reporting date, or where management’s intent is to use the investments to fund current operations or to make them available for current operations, as short-term investments.

If the estimated fair value of a debt security is below its carrying value, we evaluate whether it is more likely than not that we will sell the security before its anticipated recovery in market value and whether evidence indicating that the cost of the investment is recoverable within a reasonable period of time outweighs evidence to the contrary. We also evaluate whether or not we intend to sell the investment. If the impairment is considered to be other-than-temporary, the security is written down to its estimated fair value. In addition, we consider whether credit losses exist for any securities. A credit loss exists if the present value of cash flows expected to be collected is less than the amortized cost basis of the security. Other-than-temporary declines in estimated fair value and credit losses are included in investment and other income (loss), net.

7

Intangible assets, net

Our intangible assets are primarily comprised of acquired TUKYSA technology. The following table presents the balances of our finite-lived intangible assets for the periods presented:

(dollars in thousands)	March 31, 2022		December 31, 2021
Gross carrying value	$	305,650	$	305,650
Less: accumulated amortization	(50,748)		(45,057)
Total	$	254,902	$	260,593

The following table presents our amortization expense related to acquired TUKYSA technology costs, included in cost of sales in our condensed consolidated statements of comprehensive income (loss), for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Amortization expense	$	5,691	$	5,694

The weighted average remaining useful life of our finite-lived intangible assets was approximately 11 years as of March 31, 2022, and estimated future amortization expense related to acquired TUKYSA is $17.4 million for the nine months ending December 31, 2022, and TUKYSA technology costs is $23.1 million for each of the years ending December 31, 2023 through December 31, 2027.

Revenue recognition - Net product sales

We sell our products primarily through a limited number of specialty distributors and specialty pharmacies in the U.S, and to a lesser extent, internationally. The delivery of our products represents a single performance obligation for these transactions and we record net product sales at the point in time when control is transferred to the customer, which generally occurs upon receipt by the customer. The transaction price for net product sales represents the amount we expect to receive, which is net of estimated government-mandated rebates and chargebacks, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. We reflect these accruals as either a reduction in the related account receivable from the distributor or as an accrued liability, depending on the nature of the sales deduction. Sales deductions are based on management’s estimates that consider payor mix in target markets and experience to-date. These estimates involve a substantial degree of judgment.

Outside of the U.S., the transaction price for net product sales represents the amount we expect to receive, which is net of estimated discounts, estimated government mandated rebates, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. These estimates involve judgment in estimating net product sales.

U.S. government-mandated rebates and chargebacks: We have entered into a Medicaid Drug Rebate Agreement, or MDRA, with the Centers for Medicare & Medicaid Services. This agreement provides for a rebate based on covered purchases of our products. Medicaid rebates are invoiced to us by the various state Medicaid programs. We estimate Medicaid rebates using the expected value approach, based on a variety of factors, including payor mix and our experience to-date.

We have a Federal Supply Schedule, or FSS, agreement under which certain U.S. government purchasers receive a discount on eligible purchases of our products. In addition, we have entered into a Pharmaceutical Pricing Agreement with the Secretary of Health and Human Services, which enables certain entities that qualify for government pricing under the Public Health Services Act, or PHS, to receive discounts on their qualified purchases of our products. Under these agreements, eligible customers receive an applicable discount which is processed through the distributor as a chargeback. We estimate expected chargebacks for FSS and PHS purchases based on the expected value of each entity’s eligibility for the FSS and PHS programs. We also review historical rebate and chargeback information to further refine these estimates.

8

Distribution fees, product returns and other deductions: Our distributors charge a volume-based fee for distribution services that they perform for us. We allow for the return of product that is within a specified number of days of its expiration date or that is damaged. We estimate product returns based on our experience to-date using the expected value approach. We provide financial assistance to qualifying patients that are underinsured or cannot cover the cost of commercial coinsurance amounts through our patient support programs. Estimated contributions for commercial coinsurance under Seagen Secure are deducted from gross sales and are based on an analysis of expected plan utilization. These estimates are adjusted as necessary to reflect our actual experience.

Revenue recognition - Royalty revenues

Royalty revenues primarily reflect amounts earned under the ADCETRIS collaboration with Takeda Pharmaceutical Company Limited, or Takeda. These royalties include commercial sales-based milestones and sales royalties that relate predominantly to the license of intellectual property. Sales royalties are based on a percentage of Takeda’s net sales of ADCETRIS, with rates that range from the mid-teens to the mid-twenties based on annual net sales tiers. Takeda bears a portion of low single digit third-party royalty costs owed on its sales of ADCETRIS. This amount is included in royalty revenues. Amounts owed to our third-party licensors related to Takeda’s sales of ADCETRIS are recorded in cost of sales. These amounts are recognized in the period in which the related sales by Takeda occur. Royalty revenues also reflect amounts from Genentech, Inc., a member of the Roche Group, or Genentech, earned on net sales of Polivy, and amounts from GlaxoSmithKline earned on net sales of Blenrep.

Revenue recognition - Collaboration and license agreement revenues

We have collaboration and license agreements for our technology with a number of biotechnology and pharmaceutical companies. Under these agreements, we typically receive or are entitled to receive upfront cash payments and progress- and sales-dependent milestones for the achievement by our licensees of certain events, and annual maintenance fees and support fees for research and development services and materials provided under the agreements. We also are entitled to receive royalties on net sales of any resulting products incorporating our technology. Generally, our licensees are solely responsible for research, product development, manufacturing and commercialization of any product candidates under these collaborations, which includes the achievement of the potential milestones. Since we may not take a substantive role or control the research, development or commercialization of any products generated by some of our licensees, we may not be able to reasonably estimate when, if at all, any potential future milestone payments or royalties may be payable to us by our licensees. As such, the potential future milestone payments associated with certain of our collaboration and license agreements involve a substantial degree of uncertainty and risk that they may never be received.

Collaboration and license agreements are initially evaluated as to whether the intellectual property licenses granted by us represent distinct performance obligations. If they are determined to be distinct, the value of the intellectual property licenses would be recognized up-front while the research and development service fees would be recognized as the performance obligations are satisfied. Variable consideration is assessed at each reporting period as to whether it is not subject to future reversal of cumulative revenue and, therefore, should be included in the transaction price. Assessing the recognition of variable consideration requires significant judgment. If a contract includes a fixed or minimum amount of research and development support, this also would be included in the transaction price. Changes to collaboration and license agreements, such as the extensions of the research term or increasing the number of targets or technology covered under an existing agreement, are assessed for whether they represent a modification or should be accounted for as a new contract.

We have concluded that the license of intellectual property in certain collaboration and license agreements is not distinct from the perspective of our customers at the time of initial transfer, since we often do not license intellectual property without related technology transfer and research and development support services. Such evaluation requires significant judgment since it is made from the customer's perspective. Our performance obligations under our collaborations may include such things as providing intellectual property licenses, performing technology transfer, performing research and development consulting services, providing reagents, ADCs, and other materials, and notifying the customer of any enhancements to licensed technology or new technology that we discover, among others. We determined our performance obligations under certain collaboration and license agreements as evaluated at contract inception were not distinct and represented a single performance obligation. Upfront payments are amortized to revenue over the performance period. Upfront payment contract liabilities resulting from our collaborations do not represent a financing component as the payment is not financing the transfer of goods or services, and the technology underlying the licenses granted reflects research and development expenses already incurred by us. For agreements beyond the initial performance period, we have no remaining performance obligations. We may receive license maintenance fees and potential milestones and royalties based on collaborator development and regulatory progress, which are recorded in the period achieved in the case of milestones, and during the period of the related sales for royalties.

9

When no performance obligations are required of us, or following the completion of the performance obligation period, such amounts are recognized upon transfer of control of the goods or services to the customer. Generally, all amounts received or due other than sales-based milestones and royalties are classified as collaboration and license agreement revenues. Sales-based milestones and royalties are recognized as royalty revenue in the period the related sale occurred.

We generally invoice our collaborators and licensees on a monthly or quarterly basis, or upon the completion of the effort or achievement of a milestone, based on the terms of each agreement. Deferred revenue arises from amounts received in advance of the culmination of the earnings process and is recognized as revenue in future periods as performance obligations are satisfied. Deferred revenue expected to be recognized within the next twelve months is classified as a current liability.

2. Revenue from contracts with customers

The following table presents our disaggregated revenue for the periods presented.

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
ADCETRIS	$	180,989	$	162,573
PADCEV	100,207		69,758
TUKYSA	90,475		70,257
TIVDAK	11,415		—
Net product sales	$	383,086	$	302,588
Royalty revenues	$	28,181	$	27,219
Collaboration and license agreement revenues	$	15,193	$	2,176
Total revenues	$	426,460	$	331,983

3. Leases

We have operating leases for our office and laboratory facilities with terms that expire from 2022 through 2029. We did not record any right-of-use assets in exchange for lease liabilities during the three months ended March 31, 2022 and 2021. All of our significant leases include options for us to extend the lease term. None of our options to extend the rental term of any existing leases were considered reasonably certain as of March 31, 2022.

In June 2021, we entered into a lease agreement for an approximately 258,000 square feet building complex to be constructed by the landlord on approximately 20.5 acres of land in Everett, Washington. We intend to use the building for future manufacturing, laboratory, and office space. Under the terms of the lease, base rent is payable at an initial rate of $4.0 million per year, subject to annual escalations of 3% during the initial term of 20 years. The lease commences on the date when construction and delivery of the building shell and related improvements by the landlord have been substantially completed. We will record a lease liability and right-of-use assets on our condensed consolidated balance sheet on the lease commencement date, which has not commenced as of March 31, 2022. We have an option to renew the lease for two additional terms of ten years each. In addition, we have an option to purchase the premises in the future.

Supplemental operating lease information was as follows:

	Three Months Ended March 31,
(dollars in thousands)	2022			2021
Operating lease cost	$	4,195		$	4,014
Variable lease cost	1,072			987
Total lease cost	$	5,267		$	5,001
Cash paid for amounts included in measurement of lease liabilities	$	4,553		$	3,858
	As of March 31,
	2022			2021
Weighted average remaining lease term	5.7 years			6.0 years
Weighted average discount rate	5.0		%	5.2		%

10

Operating lease liabilities were recorded in the following captions of our condensed consolidated balance sheet as follows:

(dollars in thousands)	March 31, 2022		December 31, 2021
Accrued liabilities and other	$	13,721	$	13,905
Operating lease liabilities, long-term	53,552		56,665
Total	$	67,273	$	70,570

4. Net loss per share

Basic net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted average number of common shares and dilutive potential common shares outstanding during the period. Potentially dilutive common shares include incremental common shares issuable upon the vesting of unvested restricted stock units and the exercise of outstanding stock options, calculated using the treasury stock method.

We excluded the potential shares of common stock from the computation of diluted net income (loss) per share because their effect would have been antidilutive. The following table presents the weighted average number of shares that have been excluded for all periods presented:

	Three Months Ended March 31,
(in thousands)	2022	2021
Stock options and RSUs	10,333	10,468

5. Fair value

We have certain assets that are measured at fair value on a recurring basis according to a fair value hierarchy that prioritizes the inputs, assumptions and valuation techniques used to measure fair value. The three levels of the fair value hierarchy are:

Level 1:	Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.
Level 2:	Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly.
Level 3:	Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

The determination of a financial instrument’s level within the fair value hierarchy is based on an assessment of the lowest level of any input that is significant to the fair value measurement. We consider observable data to be market data which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market.

The fair value hierarchy of assets carried at fair value and measured on a recurring basis was as follows: 

	Fair value measurement using:
(dollars in thousands)	Quoted prices in active markets for identical assets (Level 1)		Other observable inputs (Level 2)		Significant unobservable inputs (Level 3)		Total
March 31, 2022
Short-term investments—U.S. Treasury securities	$	1,690,097	$	—	$	—	$	1,690,097
Other non-current assets—equity securities	11,230		—		—		11,230
Total	$	1,701,327	$	—	$	—	$	1,701,327
December 31, 2021
Short-term investments—U.S. Treasury securities	$	1,735,202	$	—	$	—	$	1,735,202
Other non-current assets—equity securities	14,009		—		—		14,009
Total	$	1,749,211	$	—	$	—	$	1,749,211

11

Our short-term debt investments portfolio only contains investments in U.S. Treasury and other U.S. government-backed securities. We review our portfolio based on the underlying risk profile of the securities and have a zero loss expectation for these investments. We also regularly review the securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. During the three months ended March 31, 2022 and 2021, we recognized no year-to-date credit loss related to our short- and long-term investments, and had no allowance for credit loss recorded as of March 31, 2022 or December 31, 2021.

Our debt securities consisted of the following:

(dollars in thousands)	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
March 31, 2022
U.S. Treasury securities	$	1,691,144	$	1	$	(1,048)	$	1,690,097
Contractual maturities (at date of purchase):
Due in one year or less	$	1,691,144					$	1,690,097
December 31, 2021
U.S. Treasury securities	$	1,735,388	$	12	$	(198)	$	1,735,202
Contractual maturities (at date of purchase):
Due in one year or less	$	1,635,307					$	1,635,118
Due in one to two years	100,081						100,084
Total	$	1,735,388					$	1,735,202

6. Investment and other income (loss), net

Investment and other income (loss), net consisted of the following:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
(Loss) gain on equity securities	$	(2,779)	$	259
Investment and other income, net	589		741
Total investment and other (loss) income, net	$	(2,190)	$	1,000

(Loss) gain on equity securities includes the realized and unrealized holding gains and losses on our equity securities. At times, we hold equity investments in certain companies acquired in relation to a strategic partnership. Shares held at the end of reporting periods are marked to market in our condensed consolidated financial statements, which can result in unrealized gains and losses.

7. Inventories

Inventories consisted of the following:

(dollars in thousands)	March 31, 2022		December 31, 2021
Raw materials	$	13,491	$	12,181
Work in process	216,663		152,635
Finished goods	45,593		35,847
Total	$	275,747	$	200,663

We capitalize our commercial inventory costs. Inventory that is deployed into clinical, research or development use is charged to research and development expense when it is no longer available for use in commercial sales.

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8. Accrued liabilities

Accrued liabilities consisted of the following: 

(dollars in thousands)	March 31, 2022		December 31, 2021
Employee compensation and benefits	$	83,389	$	139,052
Clinical trial and related costs	146,985		122,468
Contract manufacturing	27,147		21,867
Gross-to-net deductions and third-party royalties	88,973		81,316
Other	97,572		89,327
Total	$	444,066	$	454,030

9. Share-based compensation

The following table presents our total share-based compensation expense for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Research and development	$	23,076	$	16,964
Selling, general and administrative	20,837		21,260
Total share-based compensation expense	$	43,913	$	38,224

As of March 31, 2022, there was $137.3 million of unrecognized compensation cost related to unvested options and restricted stock unit awards, excluding our LTIPs and performance-based awards, net of forfeitures. The estimated unrecognized compensation expense related to our performance-based LTIPs was approximately $79 million as of March 31, 2022.

10. Income taxes

For the three months ended March 31, 2022, we had taxable profits in the U.S. as a result of amendments to IRC Section 174, which took effect January 1, 2022 pursuant to the 2017 Tax Cuts and Jobs Act. We recorded an income tax provision of $1.3 million, primarily related to estimated state tax liabilities for which there were limitations on the use of existing state tax carryforwards. We had existing federal tax carryforwards sufficient to offset any federal liability. Our income tax provision also reflected taxable profits in foreign jurisdictions. Our effective tax rate of approximately 0.9% differed from the federal statutory rate primarily because we have provided a valuation allowance against substantially all our deferred tax assets.

For the three months ended March 31, 2021, we did not record any income tax provision.

11. Legal matters

We are engaged in multiple legal disputes with Daiichi Sankyo Co. Ltd., or Daiichi Sankyo.

Dispute over ownership of intellectual property

We are in a dispute with Daiichi Sankyo regarding the ownership of certain technology used by Daiichi Sankyo in its cancer drug ENHERTU and certain product candidates. We believe that the linker and other ADC technology used in ENHERTU and these drug candidates are improvements to our ADC technology, the ownership of which we contend was assigned to us under the terms of a 2008 collaboration agreement between us and Daiichi Sankyo. On November 12, 2019, we submitted an arbitration demand to the American Arbitration Association seeking, among other remedies, a declaration that we are the owner of the intellectual property rights under dispute, monetary damages, and a running royalty. On April 27, 2020, the arbitrator confirmed the dispute should be resolved in arbitration. The arbitration hearing was conducted in June 2021. Recently, the arbitration hearing record was reopened by the arbitrator to consider additional evidence. A decision in the arbitration case is expected in mid-2022.

On November 4, 2019, Daiichi Sankyo filed a declaratory judgment action in the United States District Court for the District of Delaware, alleging that we are not entitled to the intellectual property rights under dispute, in an attempt to have the dispute adjudicated in federal court. The case has been stayed and administratively closed by court order.

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Patent infringement

On October 19, 2020, we filed a complaint in the United States District Court for the Eastern District of Texas to commence an action for infringement of our U.S. Patent No. 10,808,039, or the '039 Patent, by Daiichi Sankyo’s importation into, offer for sale, sale, and use in the United States of the cancer drug ENHERTU. The remedies sought in this action include, among other remedies, a judgment that Daiichi Sankyo infringed one or more valid and enforceable claims of the '039 Patent, monetary damages and a running royalty.

Daiichi Sankyo (as well as Daiichi Sankyo, Inc. and AstraZeneca Pharmaceuticals, LP, or AstraZeneca) subsequently filed an action on November 13, 2020 in the U.S. District Court for the District of Delaware seeking a declaratory judgment that ENHERTU does not infringe the ‘039 Patent. The Delaware action has been stayed by court order.

Daiichi Sankyo, Inc. and AstraZeneca also filed two petitions for post-grant review on December 23, 2020 and January 22, 2021 with the U.S. Patent and Trademark Office, or USPTO, seeking to have claims of the ‘039 Patent cancelled as unpatentable. On June 24, 2021, the USPTO issued a decision denying both petitions for post-grant review. On April 7, 2022, the Patent Trial and Appeal Board of the USPTO granted a request on rehearing and instituted two post-grant review proceedings.

On April 8, 2022, a jury in the United States District Court for the Eastern District of Texas found that Daiichi Sankyo willfully infringed the asserted claims of the '039 Patent with its ENHERTU product, and also found that the asserted claims were not invalid. The jury further awarded damages of $41.8 million for infringement from October 20, 2020 through March 31, 2022. We will record an amount of awarded damages in our condensed consolidated financial statements when we have determined the payment to be realized or realizable under ASC 450. We intend to request a royalty on Daiichi Sankyo's future sales of ENHERTU in the United States through November 5, 2024, as well as enhanced damages, attorney fees and costs.

As a result of these disputes, we have incurred and will continue to incur litigation expenses. In addition, from time to time, we may become involved in other lawsuits, claims and proceedings relating to the conduct of our business, including those pertaining to the defense and enforcement of our patent or other intellectual property rights and our contractual rights. These proceedings are costly and time consuming, and they may subject us to claims which may result in liabilities or require us to take or refrain from certain actions. Additionally, successful challenges to our patent or other intellectual property rights through these proceedings could result in a loss of rights in the relevant jurisdiction and may allow third parties to use our proprietary technologies without a license from us or our collaborators.

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Item 2.    Management’s Discussion and Analysis of Financial Condition and Results of Operations

This Quarterly Report on Form 10-Q, including the following discussion of our financial condition and results of operations, contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are based on our management’s beliefs and assumptions and on information currently available to our management. All statements other than statements of historical facts are “forward-looking statements” for purposes of these provisions, including those relating to future events or our future financial performance and financial guidance. In some cases, you can identify forward-looking statements by terminology such as “may,” “might,” “will,” “should,” “expect,” “plan,” “anticipate,” “project,” “believe,” “estimate,” “predict,” “potential,” “intend” or “continue,” the negative of terms like these or other comparable terminology, and other words or terms of similar meaning in connection with any discussion of future operating or financial performance. These statements are only predictions. All forward-looking statements included in this Quarterly Report on Form 10-Q are based on information available to us on the date hereof, and we assume no obligation to update any such forward-looking statements except as required by law. Any or all of our forward-looking statements in this document may turn out to be wrong. Actual events or results may differ materially. Our forward-looking statements can be affected by inaccurate assumptions we might make or by known or unknown risks, uncertainties and other factors. We discuss many of these risks, uncertainties and other factors in this Quarterly Report on Form 10-Q in greater detail under the heading “Part II Item 1A—Risk Factors.” We caution investors that our business and financial performance are subject to substantial risks and uncertainties.

Overview

Seagen is a biotechnology company that develops and commercializes targeted therapies to treat cancer. We are commercializing ADCETRIS®, or brentuximab vedotin, for the treatment of certain CD30-expressing lymphomas, PADCEV®, or enfortumab vedotin-ejfv, for the treatment of certain metastatic urothelial cancers, TUKYSA®, or tucatinib, for the treatment of certain metastatic HER2-positive breast cancers, and TIVDAK®, or tisotumab vedotin-tftv, for the treatment of certain metastatic cervical cancers. We are also advancing a pipeline of novel therapies for solid tumors and blood-related cancers designed to address unmet medical needs and improve treatment outcomes for patients. Many of our programs, including ADCETRIS, PADCEV and TIVDAK, are based on our ADC technology that utilizes the targeting ability of monoclonal antibodies to deliver cell-killing agents directly to cancer cells.

First quarter 2022 highlights and recent developments

Corporate

•Achieved 27% growth in net product sales for the quarter ended March 31, 2022 compared to the quarter ended March 31, 2021.

•Entered into a collaboration with Sanofi to develop and potentially commercialize multiple novel ADCs. The agreement is an exclusive collaboration that will utilize Sanofi’s proprietary monoclonal antibody technology and our proprietary ADC technology for up to three cancer targets. Under the terms of the collaboration, Seagen and Sanofi will co-fund global development activities and share equally in any future profits. In the first quarter of 2022, the first, of up to three potential targets under the collaboration, was designated, for which Sanofi paid a license fee.

•Announced that a jury found that Daiichi Sankyo willfully infringed our U.S. Patent No. 10,808,039 by selling in the U.S. its ENHERTU® product (trastuzumab deruxtecan; DS-8201). We were awarded damages of $41.8 million for past infringement of the patent. In addition, we intend to request a royalty on future sales of ENHERTU in the United States through November 5, 2024, as well as enhanced damages, attorney fees and costs.

PADCEV

•Announced the European Commission approved PADCEV as monotherapy for the treatment of adult patients with locally advanced or metastatic urothelial cancer who have previously received a platinum-containing chemotherapy and a PD-1/L1 inhibitor in April 2022.

•The UK Medicines and Healthcare products Regulatory Agency (MHRA) granted marketing authorization in Great Britain for previously treated metastatic urothelial cancer in April 2022.

•Reported initial results in patients with muscle-invasive bladder cancer, or MIBC, at the American Society of Clinical Oncology Genitourinary Cancers Symposium, or ASCO GU, in February 2022 demonstrating encouraging activity and tolerability.

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ADCETRIS

•Announced that the phase 3 ECHELON-1 clinical trial demonstrated a statistically significant improvement in OS in patients with advanced Hodgkin lymphoma following treatment with ADCETRIS in combination with chemotherapy. With approximately six years median follow up, patients receiving ADCETRIS plus chemotherapy in the frontline setting had a 41 percent reduction in the risk of death compared to those receiving chemotherapy alone.

TUKYSA

•Treated first patient in the Phase 3 HER2CLIMB-05 trial in the frontline maintenance setting for patients with metastatic HER2-positive breast cancer.

TIVDAK

•Reported initial data from the innovaTV 207 phase 2 trial of TIVDAK in solid tumors at the Multidisciplinary Head and Neck Cancers Symposium in February 2022. The results demonstrated a manageable safety profile and promising preliminary antitumor activity in patients with squamous cell carcinoma of the head and neck.

Pipeline

•The pivotal phase 2 trial of disitamab vedotin began enrolling patients with previously treated HER2-expressing metastatic urothelial cancer in April 2022.

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Our Medicines

Our approved medicines include the following:

Product*	Therapeutic Area	U.S. Approved Indication
	Hodgkin Lymphoma	Previously untreated Stage III/IV classical Hodgkin lymphoma, or cHL, in combination with doxorubicin, vinblastine and dacarbazine
		cHL at high risk of relapse or progression as post-autologous hematopoietic stem cell transplantation, or auto-HSCT, consolidation
		cHL after failure of auto-HSCT or after failure of at least two prior multi-agent chemotherapy regimens in patients who are not auto-HSCT candidates
	T-cell Lymphoma	Previously untreated systemic anaplastic large cell lymphoma, or sALCL, or other CD30-expressing peripheral T-cell lymphoma, or PTCL, including angioimmunoblastic T-cell lymphoma and PTCL not otherwise specified, in combination with cyclophosphamide, doxorubicin and prednisone
		sALCL after failure of at least one prior multi-agent chemotherapy regimen
		Primary cutaneous anaplastic large cell lymphoma, or pcALCL, or CD30-expressing mycosis fungoides who have received prior systemic therapy
	Urothelial Cancer	Locally advanced or metastatic urothelial cancer for patients who: •have previously received a programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor and platinum-containing chemotherapy, or •are ineligible for cisplatin-containing chemotherapy and have previously received one or more prior lines of therapy.
	Breast Cancer	In combination with trastuzumab and capecitabine for the treatment of adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting.
	Cervical Cancer	Recurrent or metastatic cervical cancer with disease progression on or after chemotherapy.
*ADCETRIS, PADCEV, TUKYSA and TIVDAK are only indicated for use in adults.

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ADCETRIS®

ADCETRIS is an ADC targeting CD30, which is a protein located on the surface of cells and highly expressed in Hodgkin lymphoma, certain T-cell lymphomas as well as other cancers. ADCETRIS first received U.S. Food and Drug Administration, or FDA, approval in 2011 and is now approved in a total of six indications to treat Hodgkin lymphoma and certain T-cell lymphomas in various settings including as frontline therapy.

ADCETRIS has received approval in more than 75 countries worldwide. We commercialize ADCETRIS in the U.S. and its territories and in Canada, and we collaborate with Takeda Pharmaceutical Company Limited, or Takeda, to develop and commercialize ADCETRIS on a global basis. Under this collaboration, Takeda has commercial rights in the rest of the world and pays us a royalty. Takeda has received regulatory approvals for ADCETRIS as monotherapy or in combination with other agents in various settings for the treatment of patients with Hodgkin lymphoma or CD30-positive T-cell lymphomas in Europe and many countries throughout the rest of the world and is pursuing additional regulatory approvals.

PADCEV®

PADCEV is an ADC targeting Nectin-4, a protein expressed on the surface of cells and highly expressed in bladder cancer as well as other cancers. PADCEV was granted accelerated approval by the FDA in December 2019 for the treatment of adult patients with locally advanced or metastatic urothelial cancer who have previously received a PD-1 or PD-L1 inhibitor and a platinum-containing chemotherapy before (neoadjuvant) or after (adjuvant) surgery in the locally advanced or metastatic setting. FDA approval of PADCEV was supported by data from a single-arm pivotal phase 2 clinical trial called EV-201.

In July 2021, the FDA converted PADCEV's accelerated approval to regular approval in the U.S., in addition to granting regular approval for a new indication for adult patients with locally advanced or metastatic urothelial cancer who are ineligible for cisplatin-containing chemotherapy and have previously received one or more prior lines of therapy. The conversion to regular approval was supported by the pivotal phase 3 clinical trial called EV-301, and the expanded indication was supported by data from the second cohort in the EV-201 trial. The FDA reviewed the application for regular approval under the Oncology Center of Excellence's, or OCE's, Real Time Oncology Review, or RTOR, pilot program.

In April 2022 the European Commission approved PADCEV as monotherapy for the treatment of adult patients with locally advanced or metastatic urothelial cancer who have previously received a platinum-containing chemotherapy and a PD-1/L1 inhibitor. The approval is applicable in the European Union member states, as well as Iceland, Norway and Liechtenstein.

PADCEV is also approved in Canada, Israel, Japan, Great Britain and Switzerland in previously treated metastatic urothelial cancer.

PADCEV is being co-developed and jointly commercialized with Astellas Pharma, Inc., or Astellas. In the U.S., we and Astellas are jointly promoting PADCEV. We record net sales of PADCEV in the U.S. and are responsible for all U.S. distribution activities. We and Astellas each bear the costs of our own sales organizations in the U.S., equally share certain other costs associated with commercializing PADCEV in the U.S., and equally share in any profits realized in the U.S. Outside the U.S., we have commercialization rights in all other countries in North and South America, and Astellas has commercialization rights in the rest of the world, including Europe, Asia, Australia and Africa. The agreement is intended to provide that we and Astellas will effectively equally share in costs incurred and any profits realized in all of these markets. Cost and profit sharing in Canada, the United Kingdom, Germany, France, Spain and Italy will be based on product sales and costs of commercialization. In the remaining markets, the commercializing party will bear costs and will pay the other party a royalty rate applied to net sales of the product based on a rate intended to approximate an equal profit share for both parties.

TUKYSA®

TUKYSA is an oral, small molecule tyrosine kinase inhibitor, or TKI, that is highly selective for HER2, a growth factor receptor overexpressed in certain cancers. HER2 mediates cell growth, differentiation and survival. Tumors that over-express HER2 are generally more aggressive and historically have been associated with poor overall survival, compared with HER2-negative cancers. In April 2020, TUKYSA received approval from the FDA in combination with trastuzumab and capecitabine for the treatment of adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting. FDA approval of TUKYSA was supported by data from the HER2CLIMB trial.

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The application for approval was reviewed under the FDA's RTOR pilot program. We also participated in the Project Orbis initiative of the FDA OCE which provides a framework for concurrent submission and review of oncology products among international partners. Under this program we have received approval in the U.S., Canada, Australia, Singapore, and Switzerland. In February 2021, the EC granted marketing authorization for TUKYSA in combination with trastuzumab and capecitabine for the treatment of adult patients with HER2-positive locally advanced or metastatic breast cancer who have received at least two prior anti-HER2 treatment regimens. This approval is valid in all countries of the European Union as well as Norway, Liechtenstein, Iceland and Northern Ireland. In Europe, we have begun marketing TUKYSA in Austria, France, Germany and Switzerland. Additionally, in February 2021, the UK Medicines and Healthcare products Regulatory Agency, or MHRA, granted a Great Britain marketing authorization for TUKYSA.

We are responsible for commercializing TUKYSA in the U.S., Canada and Europe. In September 2020, we entered into a license and collaboration agreement, or the TUKYSA Agreement, with Merck & Co., Inc., or Merck, pursuant to which we granted exclusive rights to Merck to commercialize TUKYSA in Asia, the Middle East and Latin America and other regions outside of the U.S., Canada and Europe. The collaboration is intended to accelerate global availability of TUKYSA.

TIVDAK®

TIVDAK is an ADC targeting tissue factor, a protein expressed on the surface of cells that has increased levels of expression on multiple solid tumors. The FDA granted accelerated approval of TIVDAK in September 2021 for the treatment of adult patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy. FDA approval was supported by data from the innovaTV 204 trial where it was evaluated in patients with recurrent or metastatic cervical cancer who had received no more than two prior systemic regimens in the recurrent or metastatic setting, including at least one prior platinum-based chemotherapy regimen. Continued approval may be contingent upon verification and description of clinical benefit in confirmatory trials.

TIVDAK is being co-developed with Genmab A/S, or Genmab, under an agreement in which the companies share all costs and profits for the product on a 50:50 basis. Under a joint commercialization agreement, we and Genmab co-promote TIVDAK in the U.S. and we record net sales of TIVDAK in the U.S. and are responsible for leading U.S. distribution activities. The companies will each maintain 50% of the sales representatives and medical science liaisons, equally share those and certain other costs associated with commercializing TIVDAK in the U.S., and equally share in any profits realized in the U.S. Outside the U.S., we have commercialization rights in the rest of the world except for Japan, where Genmab has commercialization rights. In Europe, China, and Japan, we and Genmab will equally share 50% of the costs associated with commercializing TIVDAK as well as any profits realized in these markets. In markets outside the U.S. other than Europe, China, and Japan, aside from certain costs specified in the agreement, we will be solely responsible for all costs associated with commercializing TIVDAK, and will pay Genmab a royalty based on a percentage of aggregate net sales.

Clinical Development and Regulatory Status

ADCETRIS (brentuximab vedotin)

Beyond our current labeled indications, we are evaluating ADCETRIS as monotherapy and in combination with other agents in ongoing trials, including several potential registration-enabling trials such as the phase 3 ECHELON-3 clinical trial in relapsed or refractory diffuse large B-cell lymphoma. In addition to our corporate-sponsored trials there are numerous investigator-sponsored trials of ADCETRIS in the United States. The investigator-sponsored trials include the use of ADCETRIS in a number of malignant hematologic indications and in solid tumors.

In February 2022, we announced that the phase 3 ECHELON-1 clinical trial demonstrated a statistically significant improvement in overall survival, or OS, (p=0.009) in patients with advanced Hodgkin lymphoma following treatment with ADCETRIS in combination with chemotherapy. With approximately six years median follow up, patients receiving ADCETRIS plus doxorubicin, vinblastine, and dacarbazine (A+AVD) in the frontline setting had a 41 percent reduction in the risk of death (HR 0.59; [95% CI: 0.396 to 0.879]) compared with patients receiving doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). The safety profile of ADCETRIS was consistent with previous studies and no new safety events were observed.

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PADCEV (enfortumab vedotin-ejfv)

In addition to jurisdictions where PADCEV is currently approved, applications are under review for approval in the previously treated metastatic urothelial cancer setting in Australia, under the FDA's Project Orbis program, as well as in Singapore, Brazil and other countries. In collaboration with Astellas we are conducting or planning to conduct clinical trials across the spectrum of bladder cancer including ongoing trials in frontline metastatic urothelial cancer and muscle invasive bladder cancer. We are planning to conduct a trial in non-muscle invasive bladder cancer. In addition, we are conducting a trial in a range of other solid tumors.

PADCEV is being investigated in first-line metastatic urothelial cancer and earlier stages of bladder cancer. We and Astellas are conducting a phase 1b/2 clinical trial, called EV-103, that is a multi-cohort, open-label trial of PADCEV alone or in combination with other agents. The trial is evaluating safety, tolerability and activity in locally advanced and first- and second-line metastatic urothelial cancer, and was expanded to include muscle invasive bladder cancer, or MIBC.

In February 2020, based on the positive initial results of the dose-escalation cohort and the expansion Cohort A of the EV-103 trial, the FDA granted Breakthrough Therapy designation for PADCEV in combination with pembrolizumab for the treatment of patients with unresectable locally advanced or metastatic urothelial cancer who are unable to receive cisplatin-based chemotherapy in the first-line setting. In April 2020, we announced that, based on discussions with the FDA, data from the randomized cohort K in the EV-103 trial, along with other data from the EV-103 trial, could potentially support registration under the FDA's accelerated approval pathway. The primary outcome measures are objective response rate and duration of response, or DOR. In October 2021, we completed enrollment in cohort K.

In addition to the potential accelerated approval pathway based on the EV-103 trial, we are conducting a global, registrational phase 3 trial, called EV-302, in frontline metastatic urothelial cancer in collaboration with Astellas and Merck. We, Astellas and Merck are jointly funding EV-302 and the trial is being conducted by us. EV-302 is an open-label, randomized phase 3 clinical trial evaluating the combination of PADCEV and pembrolizumab versus chemotherapy alone in patients with previously untreated locally advanced or metastatic urothelial cancer. The trial includes metastatic urothelial cancer patients who are either eligible or ineligible for cisplatin-based chemotherapy. The trial has dual primary endpoints of progression free survival and OS and is intended to support global regulatory submissions and potentially serve as a confirmatory trial if accelerated approval is granted based on EV-103.

In April 2020, we and Astellas entered into an agreement with Merck to evaluate PADCEV in MIBC. Merck has amended its ongoing phase 3 KEYNOTE-905/EV-303 registrational trial in cisplatin-ineligible patients with MIBC to include an arm evaluating PADCEV in combination with pembrolizumab. In October 2020, we and Astellas entered into an agreement with Merck to evaluate PADCEV in combination with pembrolizumab in a phase 3 trial, called KEYNOTE-B15/EV-304, to be conducted by Merck in cisplatin-eligible patients with MIBC. This trial was initiated in the first quarter of 2021.

In January 2022, we enrolled the first patient in a phase 1 trial, called EV-104, evaluating PADCEV in patients with BCG unresponsive non-muscle invasive bladder cancer.

In January 2020, we and Astellas also initiated a phase 2 clinical trial, called EV-202, to evaluate PADCEV monotherapy in solid tumors that have high-levels of Nectin-4 expression, including non-small cell lung, head and neck, gastric/esophageal and breast cancers.

TUKYSA (tucatinib)

We are conducting a broad clinical development program for TUKYSA including ongoing and planned trials in earlier lines of breast cancer and in other HER2-positive cancers. The positive results of the HER2CLIMB trial served as the basis for approval in the U.S., Canada, the European Union as well as other countries. Merck is co-funding a portion of the TUKYSA global development plan.

In December 2021, we presented new data at the San Antonio Breast Cancer Symposium from exploratory analyses from the pivotal HER2CLIMB trial showing that improvement in OS was maintained after an additional 15.6 months of follow-up when TUKYSA was combined with trastuzumab and capecitabine in patients with HER2-positive metastatic breast cancer who had stable or active brain metastases. After a median follow-up of 29.6 months, the TUKYSA regimen improved OS for patients with brain metastases by 9.1 months compared to trastuzumab and capecitabine alone (21.6 months vs. 12.5 months) (HR: 0.60; [95% CI: 0.44, 0.81]). The benefit extended to patients with active or stable brain metastases.

In October 2019, we initiated a phase 3 randomized trial, called HER2CLIMB-02, evaluating TUKYSA versus placebo, each in combination with T-DM1, for patients with unresectable locally advanced or metastatic HER2-positive breast cancer, including those with brain metastases, who have had prior treatment with a taxane and trastuzumab.

We are supporting a U.S. cooperative group, the Alliance for Clinical Trials in Oncology, that is conducting a phase 3 randomized trial, called CompassHER2 RD, which is evaluating TUKYSA in combination with T-DM1 in the adjuvant setting for patients with high-risk, HER2-positive breast cancer.

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We are also conducting a phase 2 trial, called HER2CLIMB-04, evaluating TUKYSA in combination with trastuzumab deruxtecan in previously treated locally-advanced or metastatic HER2-positive breast cancer.

We have also initiated a phase 3 trial, called HER2CLIMB-05, evaluating TUKYSA compared to placebo in combination with trastuzumab and pertuzumab in the frontline maintenance setting for patients with metastatic HER2-positive breast cancer.

We are conducting a phase 2 trial, called MOUNTAINEER, evaluating TUKYSA in combination with trastuzumab in patients with HER2-positive, RAS wild-type metastatic colorectal cancer after treatment with first- and second-line standard-of-care therapies. Initial results from 23 patients were presented at the ESMO 2019 Congress that demonstrated encouraging antitumor activity. In September 2021, we completed enrollment in the trial. We believe the trial could potentially support an application for accelerated approval in the U.S.

We are conducting a phase 2/3 trial, called MOUNTAINEER-02, in combination with trastuzumab, ramucirumab and paclitaxel in second-line HER2-positive metastatic gastroesophageal cancer. In addition, we have initiated a phase 3 trial, called MOUNTAINEER-03, in combination with trastuzumab and mFOLFOX6 in first-line HER2-positive metastatic colorectal cancer. We have also initiated a phase 1b trial evaluating TUKYSA in combination with trastuzumab and oxaliplatin based chemotherapy in first-line HER2-positive unresectable or metastatic colorectal, gastric, esophageal and gallbladder cancers.

TIVDAK (tisotumab vedotin-tftv)

In collaboration with Genmab, we are developing TIVDAK for metastatic cervical cancer and are evaluating it as a potential therapy in other solid tumors.

In January 2021, we and Genmab initiated a phase 3 clinical trial, called innovaTV 301, to evaluate TIVDAK compared to chemotherapy in patients with recurrent or metastatic cervical cancer who have received one or two prior lines of therapy. innovaTV 301 is intended to support global regulatory applications for potential approvals in regions where innovaTV 204 does not support approval and to serve as a confirmatory trial in the U.S.

We are also conducting a phase 2 clinical trial, called innovaTV 205, evaluating TIVDAK as monotherapy and in combination with certain other anti-cancer agents for first- and second-line treatment of patients with recurrent or advanced cervical cancer. In September 2021, interim results were presented at the European Society for Medical Oncology Annual Congress from two cohorts of the phase 1b/2 innovaTV 205 trial, evaluating TIVDAK as combination therapy for recurrent or metastatic cervical cancer. Both combinations showed encouraging, durable anti-tumor activity and demonstrated a manageable and acceptable safety profile.

We are conducting a phase 2 clinical trial, called innovaTV 207, for patients with relapsed, locally advanced or metastatic solid tumors. In February 2022, initial data from the innovaTV 207 phase 2 trial of TIVDAK in solid tumors was presented at the Multidisciplinary Head and Neck Cancers Symposium. The results demonstrated a manageable safety profile and promising preliminary antitumor activity in patients with squamous cell carcinoma of the head and neck with 16 percent of patients (95% CI: 5.5 to 33.7) achieving the primary endpoint of confirmed objective response rate per investigator.

Additionally, we are conducting a phase 2 clinical trial, called innovaTV 208, for patients with platinum-resistant ovarian cancer.

Disitamab vedotin

In September 2021, we and RemeGen entered into an exclusive license agreement to develop and commercialize disitamab vedotin, a novel HER2-targeted ADC, which has shown anti-tumor activity in several solid tumor types across a spectrum of HER2 levels, including urothelial, gastric and breast cancer, in all countries outside of RemeGen’s territory of Asia, excluding Japan and Singapore. We have a broad clinical development program planned including an ongoing phase 2 trial evaluating disitamab vedotin as monotherapy in previously treated HER2-expressing metastatic urothelial cancer.

Ladiratuzumab vedotin

We are developing ladiratuzumab vedotin, or LV, an ADC targeting LIV-1, which is currently being evaluated in phase 1 and phase 2 clinical trials both as monotherapy and in combination with other agents for patients with metastatic breast cancer and select solid tumors with high LIV-1 expression. In September 2020, we and Merck entered into a license and collaboration agreement, or the LV Agreement, under which the companies will jointly develop and share future costs and profits worldwide for LV.

Other clinical and early-stage product candidates

We are advancing a pipeline of early-stage clinical candidates as well as multiple preclinical and research-stage programs that employ our proprietary technologies. We advanced several product candidates into clinical development in 2021, and we plan to submit additional Investigational New Drug applications to the FDA in 2022.

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Antibody-Drug Conjugate technology license agreements

We have active technology license agreements for our ADC technology with a number of biotechnology and pharmaceutical companies, including AbbVie Biotechnology Ltd., or AbbVie; Genentech, Inc., a member of the Roche Group, or Genentech; and GlaxoSmithKline LLC, or GSK, as well as collaboration agreements with Astellas and Genmab. Genentech and GSK have received approval for ADC drugs that utilize our technology, Polivy® (polatuzumab vedotin-piic) and Blenrep® (belantamab mafodotin-blmf), respectively, in the U.S., European Union and other countries. Under our ADC license agreements with Genentech and GSK, we are entitled to receive royalties on net sales of Polivy and Blenrep worldwide.

COVID-19

We are continuing to closely monitor the impact of the evolving effects of the COVID-19 pandemic on our business. We are continuing to take proactive steps designed to protect the health and safety of our workforce, patients and healthcare professionals, to continue our business operations and to advance our goal of bringing important medicines to patients as rapidly as possible. Earlier in the pandemic, we instituted a mandatory work-from-home policy for employees who could perform their jobs offsite, but continued our essential research, manufacturing, and laboratory activities on site. More recently, we began to allow additional U.S. office-based employees who have been fully vaccinated to return to the office on a voluntary and limited basis. We maintain a number of precautionary measures designed to protect our on-site employees, such as enhanced facilities cleaning, lower concentrations of staff, contact tracing and making testing available. After pausing most in-person customer interactions in healthcare settings earlier in the pandemic, our field-based personnel are now using a mix of in-person interactions and electronic communications, such as emails, phone calls and video conferences, to support healthcare professionals and patients. We believe that the measures we have implemented are appropriate and are helping to reduce transmission of COVID-19, and we will continue to monitor conditions and related guidance from governmental authorities and adjust our activities as appropriate.

Outlook

We recognize product sales revenue from ADCETRIS in the U.S. and Canada, from PADCEV and TIVDAK in the U.S., and from TUKYSA in the U.S., Europe and Canada. We expect growth in net product sales in 2022 from 2021 to be primarily driven by sales growth of PADCEV and, to a lesser extent, TIVDAK and ADCETRIS. While we anticipate that sales of ADCETRIS will increase modestly in 2022 as compared to 2021, we have experienced continued impacts associated with the COVID-19 pandemic, which appear to have led to a reduction in the rate of Hodgkin lymphoma diagnoses and may further adversely affect the rate of Hodgkin lymphoma diagnoses in the future. We have also experienced an increase in gross-to-net deductions for ADCETRIS since the beginning of the pandemic, which has been driven by the proportion of ADCETRIS sales subject to discounts through the federal 340B drug discount program, as well as increases in discount rates. We believe that the increase in gross-to-net deductions is, in part, due to a shift in the locations where ADCETRIS is administered. We may further experience additional increases in gross-to-net deductions for ADCETRIS and the rest of our portfolio in the future based on market and site-of-care dynamics. Subject to potentially securing additional labels, we anticipate that the rate of growth of PADCEV and TUKYSA sales will decelerate in 2022 compared to 2021 as we expect to continue to more fully penetrate the markets for their currently approved labels within the U.S.

Our ability to maintain or continue to grow net product sales and to realize the anticipated benefits of our investments in our products depends on a number of factors including:

•our and our collaborators’ ability to demonstrate to the medical community the efficacy, safety and value of our products and their potential advantages compared to existing and future therapeutics in their approved indications;

•the extent to which we and our collaborators are able to obtain regulatory and other approvals of our products in additional territories and/or in additional indications, including any approvals for PADCEV in the frontline metastatic urothelial cancer setting and any approvals for TUKYSA in earlier lines of breast cancer and/or other HER2-positive cancers;

•our and our collaborators’ ability to successfully launch, market and commercialize our products in any new markets or new indications, if regulatory approval is obtained, including Astellas' ability to successfully launch, market and commercialize PADCEV in the European Union and its other markets;

•competition from other therapies and changing market dynamics, as further described in "Business—Competition" in Part I of our Annual Report on Form 10-K for the year ended December 31, 2021; for example, the potential approval of ENHERTU for second-line HER2-positive metastatic breast cancer is expected to pose increased competition for TUKYSA;

•the extent to which we are able to successfully work with Astellas to jointly market and commercialize PADCEV in the U.S., and with Genmab to jointly market and commercialize TIVDAK in the U.S.;

•our ability to successfully market and commercialize TUKYSA in our territories outside the U.S.;

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•the extent to which coverage and adequate levels of reimbursement for our products are available from governments and other third-party payors;

•the extent to which we and our collaborators are able to obtain required pricing and reimbursement approvals of our products in additional territories, most notably with respect to TUKYSA and PADCEV;

•the impact of current and future healthcare reform measures, including measures that could result in more rigorous coverage criteria or reduce the price that we receive for our products;

•the incidence flow of patients eligible for treatment in our products’ approved indications;

•our and our collaborators’ ability to accurately predict and supply product demand;

•duration of therapy for patients receiving our products;

•our and our collaborators' ability to successfully comply with rigorous post-marketing requirements, including requirements related to a confirmatory trial as a result of TIVDAK’s accelerated approval by the FDA, and to convert TIVDAK's accelerated approval to regular approval in the U.S.;

•with respect to TIVDAK, the acceptance of TIVDAK and its required eye care by the medical community and patients; and

•impacts related to the COVID-19 pandemic, including potential further adverse effects on the rate of Hodgkin lymphoma diagnoses and potential adverse impacts on diagnosis rates for other cancers.

As a result of these and other factors, our future net product sales for each of our products can be difficult to accurately predict from period to period. We cannot assure you that sales of any of our products will continue to grow or that we can maintain sales of any of our products at or near current levels.

The biopharmaceutical industry and the markets in which we operate are intensely competitive. Many of our competitors are working to develop or have commercialized products similar to those we market or are developing. Drug prices are under significant scrutiny and we expect drug pricing and other healthcare costs to continue to be subject to intense political and societal pressures on a global basis. For example, in July 2021, the Biden administration announced an Executive Order that includes initiatives aimed at lowering prescription drug costs and implementing Canadian drug importation, and in response to President Biden’s Executive Order, in September 2021, the U.S. Department of Health and Human Services released a Comprehensive Plan for Addressing High Drug Prices that outlines principles for drug pricing reform and sets out a variety of potential legislative policies that Congress could pursue to advance these principles. In addition to pricing actions and other measures being taken worldwide designed to reduce healthcare costs and limit the overall level of government expenditures, our sales and operations could also be affected by other risks of doing business internationally.

We expect that amounts received from our collaboration agreements, including royalties, will continue to be an important source of our revenues and cash flows. These revenues and cash flows will be impacted by future development funding and the achievement of development, clinical and commercial success by our collaborators under our existing collaboration and license agreements, as well as by entering into potential new collaboration and license agreements.

Our ongoing research, development, manufacturing and commercial activities will require substantial amounts of capital and may not ultimately be successful. We expect that we will incur substantial expenses, and we will require significant financial resources and additional personnel in order to advance the development of, to pursue, obtain and maintain regulatory approvals for, and to commercialize our products and product candidates, and expand our pipeline. In addition, we may pursue new operations or continue the expansion of our existing operations, including with respect to the continued development of our commercial infrastructure in Europe and our plans to otherwise continue to expand our operations internationally. As a result, we may need to raise additional capital, and our operating expenses may fluctuate as a result of such activities. We may also incur substantial milestone payment obligations to certain of our licensors, including RemeGen, as our product candidates progress through clinical trials towards potential commercialization.

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We are closely evaluating the impacts of the evolving effects of the COVID-19 pandemic on our ability and the ability of our collaborators to effectively market, sell and distribute our products and to develop our products and product candidates. Our field-based personnel are using a mix of in-person interactions and electronic communications, such as emails, phone calls and video conferences, to support healthcare providers and patients. Many healthcare professionals are facing additional demands on their time during the ongoing COVID-19 pandemic. We expect the different quality of electronic interactions as compared with in-person interactions, as well as the reduced quantity of interactions during the COVID-19 pandemic, to reduce the effectiveness of our sales personnel, as well as those of our collaborators, which could negatively affect our product sales and those of our collaborators, as well as physician awareness of our products. In this regard, we believe that the need to conduct some of our activities virtually is negatively impacting our ability to connect with key customers, including those familiar with competitive products, and our ability to conduct payor engagements. We face a number of challenges that will limit our ability to fully resume in-person interactions, including increasing COVID-19 infection rates due to coronavirus mutations and/or low vaccination rates in different areas or otherwise, the need to navigate varying restrictions for entering healthcare facilities and the pandemic's impacts on employee childcare arrangements. In addition, we may subsequently decide or be forced to resume a more restrictive remote work model, whether as a result of further spikes or surges in COVID-19 infection or hospitalization rates or otherwise. Moreover, the long-term effects of the COVID-19 pandemic are also unknown and it is possible that following the pandemic, healthcare institutions could alter their policies with respect to in person visits by pharmaceutical company representatives. Future COVID-19 related restrictions could also present product distribution challenges. The evolving effects of the COVID-19 pandemic appear to have negatively affected and may continue to negatively affect our product sales due to challenges in patient access to healthcare settings, loss of individual health insurance coverage, and inability to access government healthcare programs due to backlogs, some or all of which appear to have negatively affected diagnosis rates, may affect side effect management and course of treatment and may increase enrollment in our patient support programs. In this regard, impacts associated with the COVID-19 pandemic appear to have led to a reduction in the rate of Hodgkin lymphoma diagnoses, may have adversely affected diagnosis rates of other cancers, and may further adversely affect rates of cancer diagnoses in the future. We also expect that the conversion of medical conferences to a virtual format may reduce our ability to effectively disseminate scientific information about our products, which may result in decreased physician awareness of our products, their approved indications and their efficacy and safety.

Some of the sites participating in our clinical trials are affected by site closings, reduced capacity, staffing shortages, or other effects of the COVID-19 pandemic. At some sites, we are experiencing impacts to our ability to monitor patients, activate sites, screen and enroll patients, complete site monitoring and manage samples. The extent of the impact on a particular clinical trial depends on the current stage of activities at a given site, for example study start up versus post-enrollment, and the number of impacted sites participating in that trial. Impacts on diagnosis rates associated with the COVID-19 pandemic may also negatively impact enrollment. While we do not at this time anticipate the need to revise our publicly reported projected clinical milestone dates as a result of the effects of the COVID-19 pandemic, there may continue to be adverse impacts to our clinical study timelines, which, depending upon the duration and severity of the evolving effects of the COVID-19 pandemic, could ultimately delay data availability. Due to the suspension of data monitoring activities at sites that do not currently allow remote monitoring, as well as impacts on the ability to monitor patients, maintain patient treatment according to the trial protocols and manage samples, there is also the potential for negative impacts on data quality. While we are actively utilizing digital monitoring measures and other mitigations designed to prevent negative data quality impacts, if there were in fact a negative impact on data quality, we or our collaborators could be required to repeat, extend the duration of, or increase the size of clinical trials, which could significantly delay potential commercialization and require greater expenditures. We expect that similar factors will impact clinical studies operationalized by our collaborators. In addition, many of our non-essential on-site research activities are currently significantly reduced as a result of the COVID-19 pandemic, which may negatively impact the number of investigational new drug application, or IND, candidates entering our clinical pipeline in future years.

The extent to which the evolving effects of the COVID-19 pandemic impact our business will depend on future developments that are highly uncertain, such as coronavirus variants that may prove to be especially contagious or virulent, the ultimate duration and severity of the pandemic, government actions, such as travel restrictions, quarantines and social distancing requirements in the U.S. and in other countries, business closures or business disruptions and the effectiveness of vaccine programs and other actions taken to contain and treat the disease. For more information on the risks and uncertainties associated with the evolving effects of the COVID-19 pandemic on our business, our ability to generate sales of and revenues from our approved products, and our clinical development and regulatory efforts, see “Part II Item 1A—Risk Factors.”

Because of the above and other factors, our results of operations may vary substantially from year to year and from quarter to quarter and, as a result, we believe that period to period comparisons of our operating results may not be meaningful and should not be relied upon as being indicative of our future performance.

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Financial summary

For the three months ended March 31, 2022, our total revenues increased to $426.5 million, compared to $332.0 million for the same period in 2021. This increase was primarily driven by $80.5 million or 27% higher net product sales, due to growth from each of our approved medicines, and to a lesser extent, higher collaboration and license agreement revenues, and higher royalty revenues.

For the three months ended March 31, 2022, total costs and expenses increased to $559.5 million, compared to $454.4 million for the same period in 2021. The increase was primarily driven by higher research and development expenses, and to a lesser extent, higher cost of sales, and higher sales, general, and administrative expenses.

As of March 31, 2022, we had $2.0 billion in cash, cash equivalents and investments and $3.0 billion in total stockholders’ equity.

Results of operations

Net product sales

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
ADCETRIS	$	180,989	$	162,573	11	%
PADCEV	100,207		69,758		44	%
TUKYSA	90,475		70,257		29	%
TIVDAK	11,415		—		NM
Net product sales	$	383,086	$	302,588	27	%
NM: No amount in comparable period or not a meaningful comparison.

Our net product sales increased 27% during the three months ended March 31, 2022, as compared to the comparable period in 2021, driven by growth from each of our marketed products.

PADCEV net product sales grew primarily due to higher penetration in its approved indications, and to a lesser extent, higher sales in the current period of drug product to another company for use in its clinical trials in the current period. TUKYSA net product sales grew due to increased sales volume in our European markets and higher net product sales in the U.S. due to continued penetration in its current indication. ADCETRIS net product sales grew primarily due to higher net selling prices, and to a lesser extent, growth in volumes of vials sold. We began commercializing TIVDAK in the U.S. following FDA approval in September 2021.

We expect growth in net product sales in 2022 as compared to 2021 to be primarily driven by sales growth of PADCEV, and to a lesser extent, TIVDAK and ADCETRIS. Refer to “Overview—Outlook” above for additional information.

Gross-to-net deductions, net of related payments and credits, were as follows:

(in thousands)	Rebates and chargebacks		Distribution fees, product returns and other		Total
Balance as of December 31, 2021	$	74,889	$	16,818	$	91,707
Provision related to current period sales	129,506		10,864		140,370
Adjustment for prior period sales	(1,774)		(231)		(2,005)
Payments/credits for current period sales	(93,172)		(5,995)		(99,167)
Payments/credits for prior period sales	(26,359)		(4,151)		(30,510)
Balance as of March 31, 2022	$	83,090	$	17,305	$	100,395

Government-mandated rebates and chargebacks are the most significant component of our total gross-to-net deductions and the discount percentage has been increasing. These discount percentages increased during the three months ended March 31, 2022 as a result of price increases for ADCETRIS that we instituted that exceeded the rate of inflation. The most significant portion of our gross-to-net accrual balances as of March 31, 2022 and 2021 was for ADCETRIS Medicaid rebates. We expect future gross-to-net deductions to fluctuate based on the volume of purchases eligible for government mandated discounts and rebates, as well as changes in the discount percentage which is impacted by potential future price increases, the rate of inflation, and other factors. We expect gross-to-net deductions to increase in 2022 as compared to 2021, driven by anticipated growth in our gross product sales.

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Royalty revenues

Royalty revenues primarily reflect royalties earned under the ADCETRIS collaboration with Takeda. These royalties include commercial sales-based milestones and sales royalties. Sales royalties are based on a percentage of Takeda’s net sales of ADCETRIS, with rates that range from the mid-teens to the mid-twenties based on annual net sales tiers. Takeda bears third-party royalty costs owed on its sales of ADCETRIS. This amount is included in royalty revenues. Royalty revenues also reflect, to a lesser extent, amounts from Genentech earned on net sales of Polivy beginning in 2019 and amounts from GlaxoSmithKline earned on net sales of Blenrep beginning in 2020, both of which utilizes technology that we have licensed to them, as well as royalties on TUKYSA sales by Merck in its territory, and royalties on disitamab vedotin sales by RemeGen in its territory.

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
Royalty revenues	$	28,181	$	27,219	4	%

Royalty revenues increased slightly for the three months ended March 31, 2022 from the comparable period in 2021, primarily due to higher royalties earned on net sales of Polivy by Genentech.

We expect that royalty revenues will increase in 2022 as compared to 2021 primarily due to higher royalties from anticipated growth in ADCETRIS sales volume by Takeda, and to a lesser extent, anticipated growth of our other licensees' net product sales.

Collaboration and license agreement revenues

Collaboration and license agreement revenues reflect amounts earned under certain of our license and collaboration agreements. These revenues reflect license fees, payments received by us for technology access and maintenance fees, sales of drug supply to our collaborators, milestone payments, and reimbursement payments for research and development support that we provide to our collaborators.

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
Collaboration and license agreement revenues	$	15,193	$	2,176	NM
NM: No amount in comparable period or not a meaningful comparison.

Collaboration and license agreement revenues increased for the three months ended March 31, 2022 compared to the prior period primarily due to an upfront license payment received from Sanofi during 2022. Growth also was driven by higher amounts received from Astellas profit sharing, primarily driven by sales of PADCEV in Japan, and from drug product supplied to a collaborator.

We expect that collaboration and license agreements revenues will decline slightly in 2022 as compared to 2021. Our collaboration and license agreement revenues are impacted by the term and duration of those agreements and by progress-dependent milestones, annual maintenance fees, and reimbursement of materials and support services. Collaboration and license agreement revenues may vary substantially from year to year and quarter to quarter depending on the progress made by our collaborators with their product candidates and the timing of milestones achieved, the amount of drug supplied to our collaborators, and whether we enter into potential additional collaboration and license agreements.

Collaboration and license agreements

Takeda ADCETRIS collaboration

We have an agreement with Takeda for the global co-development of ADCETRIS and the commercialization of ADCETRIS by Takeda in its territory. We recognize payments from Takeda, including progress-dependent development and regulatory milestone payments, reimbursement for drug supplied, and net development cost reimbursement payments, as collaboration and license agreement revenues upon transfer of control of the goods or services over the development period. When the performance of development activities under the collaboration results in us making a reimbursement payment to Takeda, that payment reduces collaboration and license agreement revenues. We also recognize royalty revenues based on a percentage of Takeda's net sales of ADCETRIS in its territories, ranging from the mid-teens to the mid-twenties based on annual net sales tiers, as well as sales-based milestones. Takeda bears a portion of third-party royalty costs owed on its sales of ADCETRIS, which is included in royalty revenues.

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Astellas PADCEV collaboration

We have a collaboration agreement with Agensys, Inc., which subsequently became an affiliate of Astellas, to jointly research, develop and commercialize ADCs for the treatment of several types of cancer. Under this collaboration, we and Astellas are equally co-funding all development and certain commercialization costs for PADCEV. In the U.S., we and Astellas jointly promote PADCEV. We record sales of PADCEV in the U.S. and are responsible for all U.S. distribution activities. The companies each bear the costs of their own sales organizations in the U.S., equally share certain other costs associated with commercializing PADCEV in the U.S., and equally share in any profits realized in the U.S. Gross profit share payments owed to Astellas in the U.S. under the joint commercialization agreement are recorded in cost of sales. Outside the U.S., we have commercialization rights in all countries in North and South America, and Astellas has commercialization rights in the rest of the world, including Europe, Asia, Australia and Africa.

Astellas or its affiliates are responsible for manufacturing PADCEV for development and commercial use. However, we are responsible for packaging and labeling in countries in which we sell PADCEV. In addition, if the parties determine that a second source is required, we will be responsible for establishing such second source whether internally or through a third party.

Genmab TIVDAK collaboration

We have an agreement with Genmab to develop and commercialize ADCs for the treatment of several types of cancer, under which we previously exercised a co-development option for TIVDAK. Under this collaboration, we and Genmab are co-funding all development costs for TIVDAK. In the U.S., we and Genmab co-promote TIVDAK. We record sales of TIVDAK in the U.S. and are responsible for leading U.S. distribution activities. The companies will each maintain 50% of the sales representatives and medical science liaisons, equally share those and certain other costs associated with commercializing TIVDAK in the U.S., individually bear the costs of certain other personnel in the U.S., and equally share in any profits realized in the U.S. Outside the U.S., we have commercialization rights in the rest of the world except for Japan, where Genmab has commercialization rights. In Europe, China, and Japan, we and Genmab equally share 50% of the costs associated with commercializing TIVDAK as well as any profits realized in these markets. In markets outside the U.S. other than Europe, China, and Japan, aside from certain costs specified in the agreement, we are solely responsible for all costs associated with commercializing TIVDAK and will pay Genmab a royalty based on a percentage of aggregate net sales ranging from the mid-teens to mid-twenties.

Merck LV collaboration

In 2020, we entered into the LV Agreement with a subsidiary of Merck. We are pursuing a broad joint development program evaluating LV as monotherapy and in combination setting, including with Merck’s anti-PD-1 therapy KEYTRUDA® (pembrolizumab) in triple-negative breast cancer, hormone receptor-positive breast cancer and other LIV-1-expressing solid tumors. Under the terms of the LV Agreement, we granted Merck a co-exclusive worldwide development and commercialization license for LV, and agreed to jointly develop and commercialize LV on a worldwide basis. We received an upfront cash payment, and we are eligible to receive milestone payments upon the initiation of certain clinical trials, regulatory approval in certain major markets and achievement of specified annual global net sales thresholds of LV. Each company is responsible for 50% of global costs to develop and commercialize LV and will receive 50% of potential future profits.

We recognize such cost sharing proportionately with the performance of the underlying activities, while recording Merck’s reimbursement of our expenses as a reduction of research and development expenses.

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Merck TUKYSA collaboration

In 2020, we entered into the TUKYSA Agreement with a subsidiary of Merck. We granted exclusive rights to commercialize TUKYSA in Asia, the Middle East and Latin America and other regions outside of the U.S., Canada and Europe. Under the terms of the TUKYSA Agreement, Merck is responsible for marketing applications for approval in its territory, supported by the positive results from the HER2CLIMB clinical trial. We retained commercial rights in, and will record sales in, the U.S., Canada and Europe. Merck is also co-funding a portion of the TUKYSA global development plan, which encompasses several ongoing and planned trials across HER2-positive cancers. We will continue to lead ongoing TUKYSA global development operational execution. Merck will solely fund and conduct country-specific clinical trials necessary to support anticipated regulatory applications in its territories. We are eligible to receive progress-dependent milestone payments, and are entitled to receive tiered royalties on sales of TUKYSA by Merck that begin in the low twenty percent range and escalate based sales volume by Merck in its territory.

We recognize such cost sharing proportionately with the performance of the underlying activities, while recording Merck’s reimbursement of our expenses as a reduction of research and development expenses. Sales of TUKYSA drug product supplied is included in collaboration and license agreement revenues. The $85.0 million prepayment received for global development cost-sharing was recorded as a co-development liability in accrued liabilities and other or other long-term liabilities on our condensed consolidated balance sheet as of March 31, 2022. As joint development expenses are incurred, we recognize the portion of Merck’s prepayment as a reduction of our research and development expenses on our condensed consolidated statements of comprehensive loss. As of March 31, 2022 and December 31, 2021, $48.4 million and $55.3 million was recorded as the remaining co-development liability, respectively.

RemeGen disitamab vedotin license agreement

Effective in September 2021, we and RemeGen entered into an exclusive worldwide licensing agreement to develop and commercialize disitamab vedotin, a novel HER2-targeted ADC. Disitamab vedotin combines the drug-linker technology originally developed by Seagen with RemeGen’s novel HER2 antibody. Disitamab vedotin received FDA Breakthrough Therapy designation in 2020 for use in second-line treatment of patients with HER2-expressing, locally advanced or metastatic urothelial cancer who have previously received platinum-containing chemotherapy. Also in 2020, RemeGen announced FDA’s clearance of an IND application for a phase II clinical trial in locally advanced or metastatic urothelial cancer. Disitamab vedotin is conditionally approved for treating locally advanced metastatic gastric cancer in China, and in July 2021 the National Medical Products Administration of China also accepted a NDA for disitamab vedotin in locally advanced or metastatic urothelial cancer.

Under the terms of the agreement, we made a $200.0 million upfront payment to obtain exclusive license rights to disitamab vedotin for global development and commercialization, outside of RemeGen’s territory. RemeGen retains development and commercialization rights for Asia, excluding Japan and Singapore. We will lead global development and RemeGen will fund and operationalize the portion of global clinical trials attributable to its territory. RemeGen will also be responsible for all clinical development and regulatory submissions specific to its territory. We will pay RemeGen up to $195.0 million in potential milestone payments across multiple indications and products based upon the achievement of specified development goals, and up to $2.2 billion in potential milestone payments based on the achievement of specified regulatory and commercialization goals. RemeGen will be entitled to a tiered, high single digit to mid-teen percentage royalty based on net sales of disitamab vedotin in our territory.

Other technology collaboration and license agreements

We have other collaboration and license agreements for our ADC technology with a number of biotechnology and pharmaceutical companies. We typically receive upfront cash payments and progress- and sales-dependent milestones for the achievement by our licensees of certain events, and annual maintenance fees and support fees for research and development services and materials provided under the agreements. These amounts are recognized as revenue over the performance obligation period if the license is determined not to be distinct from other goods and services provided, or, if there is no performance obligation, upon transfer of control of the goods or services to the customer.

Cost of sales

Cost of sales includes manufacturing and distribution costs of product sold, gross profit share with Astellas and Genmab pursuant to those respective collaborations, amortization of acquired technology license costs, royalties owed on our PADCEV net product sales, and royalties owed on global ADCETRIS, TUKYSA, and TIVDAK net product sales.

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	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
Cost of sales	$	87,626	$	64,135	37	%

Cost of sales increased for the three months ended March 31, 2022 from the comparable period in 2021, driven by higher gross profit sharing owed to our collaboration partners, and to a lesser extent, higher product costs from sales volume increases. The gross profit share owed to collaborators totaled $52.8 million for the three months ended March 31, 2022, as compared to $32.5 million for the comparable period in 2021.

We expect cost of sales to increase in 2022 as compared to 2021 as a result of the net product sales growth of our marketed products, contributing to higher anticipated gross profit sharing with our collaborators, higher manufacturing costs for products sold, and increased royalties owed on certain net sales of our products.

Research and development

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
Research and clinical development	$	229,649	$	174,005	32	%
Process sciences and manufacturing	68,010		56,421		21	%
Total research and development	$	297,659	$	230,426	29	%

Research and clinical development expenses include personnel, occupancy and laboratory expenses, technology access fees, preclinical translational biology and in vitro and in vivo studies, IND-enabling pharmacology and toxicology studies, and external clinical trial costs including costs for clinical sites, clinical research organizations, contractors and regulatory activities associated with conducting human clinical trials. The increase for the three months ended March 31, 2022 from the comparable period in 2021 was due mainly to higher employee-related costs and clinical trial costs mainly to support our early- and late-stage pipeline of product candidates.

Process sciences and manufacturing expenses include personnel and occupancy expenses, manufacturing costs for the scale-up and pre-approval manufacturing of product candidates used in research and our clinical trials, and costs for drug product supplied to our collaborators. Process sciences and manufacturing expenses also include quality control and assurance activities, and storage and shipment of our product candidates. The increase for the three months ended March 31, 2022 from the comparable period in 2021 primarily reflected higher manufacturing costs of our product candidates for use in clinical trials.

We utilize our employee and infrastructure resources across multiple research and development projects. We track human resource efforts expended on many of our programs for purposes of billing our collaborators for time incurred at agreed upon rates and for resource planning. We do not account for actual costs on a project basis as it relates to our infrastructure, facility, employee and other indirect costs; however, we do separately track significant third-party costs including clinical trial costs, manufacturing costs and other contracted service costs on a project basis. To that end, the following table shows third-party costs incurred for research, contract manufacturing of our product candidates and clinical and regulatory services, as well as development milestone payments for in-licensed technology for our products and certain of our clinical-stage product candidates. The table also presents other costs and overhead consisting of third-party costs for our preclinical stage programs, personnel, facilities, manufacturing, and other indirect costs not directly charged to development programs, as well as cost reimbursements received from or payments made to collaborators related to our product candidates.

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	Three months ended March 31,
(dollars in thousands)	2022		2021
TUKYSA (tucatinib)	$	43,595	$	29,993
PADCEV (enfortumab vedotin-ejfv)	24,769		16,288
ADCETRIS (brentuximab vedotin)	13,852		17,076
TIVDAK (tisotumab vedotin)	7,932		12,004
Ladiratuzumab vedotin	3,259		4,845
Disitamab vedotin	10,380		—
Other clinical stage programs	20,533		21,596
Total third-party costs for clinical stage programs	124,320		101,802
Other costs, overhead, and net cost-sharing with collaborators	173,339		128,624
Total research and development	$	297,659	$	230,426

Third-party costs for PADCEV increased for the three months ended March 31, 2022 as compared to the 2021 period, due primarily to higher clinical trials expenses.

Third-party costs for TUKYSA increased for the three months ended March 31, 2022 as compared to the 2021 period, due primarily to higher manufacturing costs as well as higher clinical trials expenses.

Third-party costs for ADCETRIS, TIVDAK, and ladiratuzumab vedotin decreased for the three months ended March 31, 2022 as compared to the 2021 period, due primarily to the timing of clinical trials.

We obtained exclusive license rights to disitamab vedotin for global development and commercialization outside of RemeGen’s territory in September 2021.

Third-party costs for other clinical stage programs were consistent for the three months ended March 31, 2022 as compared to the 2021.

Other costs, overhead, and net cost-sharing with collaborators increased for the three months ended March 31, 2022 from the comparable period in 2021, due to higher employee-related costs and a payment for in-licensed technology. During the three months ended March 31, 2022 and 2021, net cost-sharing reimbursements from and payments made to collaborators were $23.3 million and $21.3 million, respectively.

In order to advance our product candidates toward commercialization, the product candidates are tested in numerous preclinical safety, toxicology and efficacy studies. We then conduct clinical trials for those product candidates that take several years or more to complete. The length of time varies substantially based upon the type, complexity, novelty and intended use of a product candidate. We will also need to conduct additional clinical trials in order to expand labeled indications of use for our commercial products. The outcome of our clinical trials is uncertain. The cost of clinical trials may vary significantly as a result of a variety of factors, including the number of patients enrolled, patient site costs, quantity and source of drug supply required, safety and efficacy of the product candidate, and extent of regulatory efforts, among others. 

We anticipate that our total research and development expenses in 2022 will increase compared to 2021 primarily due to higher costs for the continued development of our approved products and product candidates, offset in part by the $200.0 million RemeGen upfront license payment in 2021.

The risks and uncertainties associated with our research and development projects are discussed more fully in “Part II Item 1A—Risk Factors.” As a result of these risks and uncertainties, we are unable to determine with any degree of certainty the duration and completion costs of our research and development projects, anticipated completion dates, or when and to what extent we will receive cash inflows from the commercialization and sale of our products in any additional approved indications or of any of our product candidates.

Selling, general and administrative 

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
Selling, general and administrative	$	174,225	$	159,842	9	%

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Selling, general and administrative expenses increased for the three months ended March 31, 2022 from the comparable period in 2021, reflecting investments to support our ongoing European TUKYSA launches and the U.S. commercial launch of TIVDAK.

We anticipate that selling, general and administrative expenses will increase in 2022 as compared to 2021 as we continue our commercial activities in support of our product launches, and invest in infrastructure to support our continued growth in the U.S. and Europe.

Investment and other (loss) income , net

	Three months ended March 31,
(dollars in thousands)	2022		2021		% Change
(Loss) gain on equity securities	$	(2,779)	$	259	NM
Investment and other income, net	589		741		(21)	%
Total investment and other (loss) income, net	$	(2,190)	$	1,000	(319)	%
NM: No amount in comparable period or not a meaningful comparison.

Investment and other (loss) income , net includes other non-operating income and loss, such as unrealized holding gains and losses on equity securities, realized gains and losses on equity and debt securities, and amounts earned on our investments in U.S. Treasury securities.

The loss on equity securities for the three months ended March 31, 2022 was due to unrealized holding losses resulting from a decline in the share price of securities held during the period.

Provision for income taxes

Our provision for income taxes was $1.3 million for the three months ended March 31, 2022 compared with $0.0 million for the three months ended March 31, 2021. The provision for income taxes in the 2022 period primarily related to taxable profits in the U.S. as a result of amendments to IRC Section 174, which took effect January 1, 2022 pursuant to the 2017 Tax Cuts and Jobs Act. We had existing federal tax carryforwards sufficient to offset any federal liability; however, there were limitations on the use of existing state tax carryforwards. Our income tax provision also reflected taxable profits in foreign jurisdictions.

Liquidity and capital resources

(in thousands)	March 31, 2022		December 31, 2021
Cash, cash equivalents, and investments	$	1,951,093	$	2,160,036
Working capital	2,239,961		2,300,340
Stockholders’ equity	2,998,467		3,065,139

	Three months ended March 31,
(in thousands)	2022		2021
Cash provided (used) by:
Operating activities	$	(216,812)	$	(125,326)
Investing activities	26,663		(78,715)
Financing activities	26,664		19,791

The change in net cash from operating activities for the three months ended March 31, 2022 as compared to the comparable period in 2021 was primarily related to an increase in net loss and increases in net working capital.

The change in net cash from investing activities for the three months ended March 31, 2022 as compared to the comparable period in 2021 reflected differences between the proceeds received from sale and maturity of our investments and amounts reinvested and the difference for purchases of property, plant, and equipment.

The change in net cash from financing activities for the three months ended March 31, 2022 as compared to the comparable period in 2021 was driven by the higher proceeds from the exercise of stock options and employee stock purchase plan.

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We primarily have financed our operations through the issuance of our common stock, collections from commercial sales of our products, amounts received pursuant to license and collaboration agreements, and royalty revenues. To a lesser degree, we also have financed our operations through investment income. These financing and revenue sources have allowed us to maintain adequate levels of cash and investments.

Our cash, cash equivalents, and investments are held in a variety of non-interest bearing bank accounts and interest-bearing instruments subject to investment guidelines allowing for holdings in U.S. government and agency securities, corporate securities, taxable municipal bonds, commercial paper and money market accounts. Our investment portfolio is structured to provide for investment maturities and access to cash to fund our anticipated working capital needs. However, if our liquidity needs should be accelerated for any reason in the near term, or investments do not pay at maturity, we may be required to sell investment securities in our portfolio prior to their scheduled maturities, which may result in a loss. As of March 31, 2022, we had $2.0 billion held in cash, cash equivalents and investments.

At our currently planned spending rates, we believe that our existing financial resources, together with product and royalty revenues, and reimbursements and profit sharing we expect to receive under our existing collaboration and license agreements, will be sufficient to fund our operations for at least the next twelve months from the date of this filing.

We expect to make additional capital outlays and to increase operating expenditures over the next several years as we hire additional employees, and support our development, commercialization, invest in our facilities, and expand globally, which may require us to raise additional capital. In addition, we may pursue new operations or continue the expansion of our existing operations, including with respect to the continued development of our commercial infrastructure in Europe and our plans to otherwise continue to expand our operations internationally. Our commitment of resources to the continuing development, regulatory and commercialization activities for our products, the continued research, development and manufacturing of our product candidates, our pursuit of regulatory approvals for and preparing to potentially launch and commercialize our product candidates, and the anticipated expansion of our pipeline and operations may require us to raise additional capital. Further, we actively evaluate various strategic transactions on an ongoing basis, including licensing or otherwise acquiring complementary products, technologies or businesses, and we may require significant additional capital in order to complete or otherwise provide funding for such transactions. We may seek additional capital through some or all of the following methods: corporate collaborations, licensing arrangements, and public or private debt or equity financings. We have no committed sources of funding and do not know whether additional capital will be available when needed, or that, if available, we will obtain financing on terms favorable to us or our stockholders. If we are unable to raise additional funds when we need them, we may be required to scale back our operations, delay, reduce the scope of, or eliminate development programs enter into collaboration or license agreements on terms that are not favorable to us, sell or relinquish rights to certain assets, proprietary technologies or product candidates or forego strategic opportunities.

Material Cash Requirements

Our material cash requirements in the short- and long-term consist of the following operational, capital, and manufacturing expenditures, a portion of which contain contractual or other obligations. We plan to fund our material cash requirements with our current financial resources together with our anticipated receipts of accounts receivable, product sales and royalty revenues, and reimbursements we expect to receive under our existing collaboration and license agreements.

Operating expenditures. Our primary uses of cash and operating expenses relate to paying employees and consultants, administering clinical trials, marketing our products, and providing technology and facility infrastructure to support our operations. Our research and development expenses for the three months ended March 31, 2022 were $297.7 million, and we expect to increase our investment in research and development expenses in 2022 as compared to 2021. Our sales, general and administrative expenses were $174.2 million for the three months ended March 31, 2022, and we expect to increase our sales, general, and administrative expenses to support our business growth in 2022 as compared to 2021. On a long-term basis, we manage future cash requirements relative to our long-term business plans.

Operating costs also relate to our building leases for our office and laboratory facilities expiring in 2022 through 2029 that contain rate escalations and options for us to extend the leases. Our future minimum lease payments as of March 31, 2022 totaled $16.8 million related to short-term lease liabilities, and $61.1 million related to long-term lease liabilities. We signed a 20-year lease in June 2021 for a building complex in Everett, Washington that has not commenced as of March 31, 2022, and therefore rent payments are not included in lease liability balances as of March 31, 2022. Refer to Note 3 in the Notes to Financial Statements in Item 1 for further detail of our lease obligations.

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Capital expenditures. We make investments in our office, laboratory, and manufacturing facilities to enable continued expansion of our business. These include leasehold and building improvements at our approximately 1 million square feet of leased and owned properties, installation of laboratory and manufacturing equipment, computers, software, and office equipment. Our purchases for property and equipment for the three months ended March 31, 2022 were $17.4 million, and we anticipate these investments to grow in 2022 as compared to 2021 to support our anticipated business growth and long-term facility needs, including a significant multi-year investment in a building complex being constructed in Everett, Washington, which is expected to provide us additional manufacturing, laboratory, and office space in the future. We expect our capital expenditures for this Everett facility to be approximately $350 million to $400 million through 2024.

Manufacturing costs, and supply agreements. Some of our inventory components and products require long lead times to manufacture. Therefore, we make substantial and often long-term investments in our supply chain in order to ensure we have enough drug product to meet current and future revenue forecasts, as well as clinical trial needs. Supply agreements primarily include non-cancelable obligations under our manufacturing, license and collaboration, and technology agreements. Further, a substantial portion of those non-cancelable obligations include minimum payments related to manufacturing our product candidates for use in our clinical trials and for commercial operations in the case of ADCETRIS. There have been no material changes related to our future minimum contractual commitments under these arrangements as disclosed in our Annual Report on Form 10-K for the year ended December 31, 2021 filed February 9, 2022.

Royalties, milestones and profit-sharing associated with our licensed technology and collaboration agreements. Some of our license and collaboration agreements provide for periodic maintenance fees over specified time periods, profit share payments, and/or payments by us upon the achievement of development and regulatory milestones. Some of our licensing agreements also obligate us to pay royalties based on net sales of products utilizing licensed technology. Such royalties and profit share payments are dependent on future product sales and are contingent on events that have not yet occurred. Royalties and profit share payments totaled $65.7 million for the three months ended March 31, 2022 and are expected to increase in future periods. Milestone payments generally become due and payable upon the achievement of certain events. There have been no material changes related to our future milestone payments potentially owed related to in-licensed technology as disclosed in our Annual Report on Form 10-K for the year ended December 31, 2021 filed February 9, 2022.

Critical accounting policies

The preparation of financial statements in accordance with GAAP requires us to make estimates, assumptions, and judgments that affect the amounts reported in our financial statements and accompanying notes. We evaluate our estimates on an ongoing basis. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form our basis for making judgments about the carrying values of assets and liabilities and the reported amounts of revenues and expenses that are not readily apparent from other sources. Actual results may differ from those estimates. Our critical accounting policies, those with the more significant judgments and estimates, used in the preparation of our financial statements for the three months ended March 31, 2022 were consistent with those in Part II Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2021.

Item 3.    Quantitative and Qualitative Disclosures About Market Risk

There have been no material changes to our market risk disclosures as set forth in Part II Item 7A of our Annual Report on Form 10-K for the year ended December 31, 2021.

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Item 4.    Controls and Procedures

(a) Evaluation of disclosure controls and procedures. Our management, with the participation of our Chief Executive Officer and our Chief Financial Officer, have evaluated our disclosure controls and procedures (as defined in Rules 13a-15(e) under the Securities Exchange Act of 1934, as amended) prior to the filing of this quarterly report. Based on that evaluation, our Chief Executive Officer and our Chief Financial Officer have concluded that, as of the end of the period covered by this quarterly report, our disclosure controls and procedures were, in design and operation, effective at the reasonable assurance level.

A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Because of inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues, if any, within an organization have been detected. Accordingly, our disclosure controls and procedures are designed to provide reasonable, not absolute, assurance that the objectives of our disclosure control system are met.

(b) Changes in internal control over financial reporting. There have not been any changes in our internal control over financial reporting during the quarter ended March 31, 2022 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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Part II. Other Information

Item 1.    Legal Proceedings

The information required to be set forth under this Item 1 is incorporated by reference to “Note 11. Legal matters” of the Notes to Condensed Consolidated Financial Statements included in Part 1 Item 1 of this Quarterly Report on Form 10-Q.

Item 1A.    Risk Factors

You should carefully consider the following risk factors, in addition to the other information contained in this Quarterly Report on Form 10-Q, including our condensed consolidated financial statements and related notes. If any of the events described in the following risk factors occurs, our business, operating results and financial condition could be seriously harmed. This Quarterly Report on Form 10-Q also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in the forward-looking statements as a result of factors that are described below and elsewhere in this Quarterly Report on Form 10-Q.

Risk Factor Summary

Below is a summary of material factors that make an investment in our securities speculative or risky. Importantly, this summary does not address all of the risks that we face. Additional discussion of the risks and uncertainties summarized in this risk factor summary, as well as other risks that we face, follows this summary. This summary is qualified in its entirety by that more complete discussion of such risks and uncertainties.

•Our success depends on our ability to effectively commercialize our products. If we and our collaborators are unable to effectively commercialize our products and to expand their utilization, our ability to generate significant revenue and our prospects for profitability will be adversely affected.

•Our success also depends on our ability to obtain regulatory approvals for our product candidates and for our current products in additional territories, as well as our ability to expand the labeled indications of use for our current products. Our inability to do so could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

•Reports of adverse events or safety concerns involving our products or product candidates could delay or prevent us from obtaining or maintaining regulatory approvals or could negatively impact sales of our products or the prospects for our product candidates.

•Clinical trials and product development are expensive, time consuming and uncertain, may take longer than we expect and may not be successful. Our failure to effectively advance our development programs in a timely manner or at all could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

•The successful commercialization of our products will depend, in part, on the extent to which governmental authorities and health insurers establish adequate coverage and reimbursement levels and pricing policies.

•The successful commercialization of our products will also depend in part on the acceptance of our products by the medical community, patients and third-party payors.

•Any failures or setbacks in our antibody-drug conjugate, or ADC, development program or our other platform technologies could negatively affect our business and financial position.

•We face intense competition and rapid technological change, which may result in others discovering, developing or commercializing competing products before or more successfully than we do.

•Our products and any future approved products remain subject to extensive ongoing regulatory obligations and oversight, including post-approval requirements, that could result in penalties and significant additional expense and could negatively impact our and our collaborators’ ability to commercialize our current and any future approved products.

•Healthcare law and policy changes may negatively impact our business, including by decreasing the prices that we and our collaborators receive for our products.

•We are subject to various state, federal and international laws and regulations, including healthcare, data privacy and information security laws and regulations, that may impact our business and could subject us to significant fines and penalties or other negative consequences.

•Our collaborators and licensees may not perform as expected, which may negatively affect our ability to develop and commercialize our products and product candidates and/or generate revenues through technology licensing, and may otherwise negatively affect our business.

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•We currently rely on third-party manufacturers and other third parties for production of our drug products, and our dependence on these third parties may impair the continued development and commercialization of our products and product candidates.

•If we are unable to enforce our intellectual property rights or if we fail to sustain and further procure additional intellectual property rights, we may not be able to successfully commercialize our products or any future products and competitors may be able to develop competing therapies.

•We and our collaborators rely on license agreements for certain aspects of our products and product candidates and technologies such as our ADC technology. Failure to maintain these license agreements or to secure any required new licenses could prevent us from continuing to develop and commercialize our products and product candidates.

•We have been and may in the future be subject to litigation, which could result in substantial expenses and damages and may divert management’s time and attention from our business.

•The evolving effects of the COVID-19 pandemic and associated global economic instability could have further adverse effects on our business, including our commercialization efforts, supply chain, regulatory activities, clinical development activities and other business operations.

•If we are unable to manage our growth, our business, results of operations, financial condition and growth prospects may be adversely affected.

•Risks associated with our expanding operations in countries outside the U.S. could materially adversely affect our business.

•Our operating results are difficult to predict and may fluctuate. If our operating results are below the expectations of securities analysts or investors, the trading price of our stock could decline.

•We have a history of net losses. We expect to continue to incur net losses and may not achieve future sustained profitability for some time, if at all.

•Our stock price is volatile and our shares may suffer a decline in value.

•Our existing stockholders have significant control of our management and affairs.

Risks Related to Our Products, Product Candidates and Research and Development

Our success depends on our ability to effectively commercialize our products. If we and our collaborators are unable to effectively commercialize our products and to expand their utilization, our ability to generate significant revenue and our prospects for profitability will be adversely affected.

Our ability to generate revenue from product sales and our prospects for profitability are substantially dependent on our and our collaborators’ ability to effectively commercialize our products and expand their utilization. We may not be able to fully realize the commercial potential of our products, and/or commercial sales of our products may be lower than our projections, for a number of reasons, including:

•we and our collaborators may be unable to effectively launch, market and commercialize our products, including in any new markets or in any new indications;

•we and our collaborators may not be able to establish or demonstrate to the medical community the efficacy, safety and value of our products and their potential advantages compared to existing and future therapeutics in their approved indications;

•we and our collaborators may not be able to obtain and maintain regulatory and other required governmental approvals to market our products in any additional territories or for any additional indications;

•new competitive therapies in the approved indications for our products have been approved by regulatory authorities or may be approved or submitted to regulatory authorities for approval in the near term;

•there may continue to be new adverse results, adverse events or safety concerns reported in connection with the use of our products, including in clinical trials;

•there may be additional changes to the labeling for our products that further restrict how we market and sell our products, including as a result of data collected from clinical trials and/or as a result of the use of our products;

•the incidence rate of new patients or the duration of therapy in the approved indications for our products may be lower than our projections;

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•negative impacts related to the COVID-19 pandemic, including potential further impacts on cancer diagnosis rates, may increase or become more severe;

•we may encounter challenges in joint decision making and joint execution with our collaborators that adversely affect product sales;

•co-promotion arrangements, such as the joint commercialization of PADCEV with Astellas in the U.S. and the joint commercialization of TIVDAK with Genmab in the U.S., may not be successful;

•our products may be impacted by adverse reimbursement and coverage policies from government and private payors such as Medicare, Medicaid, insurance companies, health maintenance organizations and other plan administrators, or may be subject to pricing pressures enacted by industry organizations or state and federal governments, including as a result of increased scrutiny over pharmaceutical pricing, the cost of alternative treatment options or otherwise;

•we and our collaborators may not be able to obtain favorable pricing and reimbursement approvals in additional territories in a timely manner or at all;

•physicians may be reluctant to prescribe our products due to side effects associated with their use or until longer term efficacy and safety data exist;

•regulatory restrictions may change or increase;

•we and our collaborators may not have adequate financial or other resources to effectively commercialize our products; and

•we and our collaborators may not be able to accurately predict demand for our products and obtain adequate commercial supplies of our products to meet demand at an acceptable cost.

Our ability to grow our product sales in future periods is also dependent on price increases, and we periodically increase the price of our products. Price increases on our products, as well as negative publicity regarding drug pricing and increases in drug prices generally, whether on our products or products distributed by other pharmaceutical companies, could negatively affect market acceptance of, and sales of, our products. In any event, we cannot assure you that price increases we have taken or may take in the future will not negatively affect our future product sales.

If we and our collaborators are unable to successfully commercialize our products or if sales of a product do not reach the levels we expect, then our business, results of operation, financial condition and growth prospects could be adversely affected.

Our success also depends on our ability to obtain regulatory approvals for our product candidates and for our current products in additional territories, as well as our ability to expand the labeled indications of use for our current products. Our inability to do so could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

We and our collaborators are required to obtain marketing approvals from applicable regulatory authorities in order to market our products or to expand the labeled indications of use for our current marketed products. However, regulatory review is a lengthy and expensive process, and approval is highly uncertain.

The FDA and other regulatory agencies have substantial discretion in the approval process and in determining when or whether regulatory approval will be obtained. Clinical trial data are subject to differing interpretations. Even if we believe data are promising, regulatory authorities may disagree and may require additional data, limit the scope of the approval or deny approval altogether. For example, although applications for approval of PADCEV were submitted to various regulatory authorities based on results from the EV-201 and EV-301 trials, regulatory authorities may not approve these applications in a timely manner or at all. In addition, the approval of a product candidate by one regulatory agency does not mean that other regulatory agencies will also approve such product candidate.

Any approval that a product does receive may be more restricted than anticipated. For example, regulatory authorities may approve a product for fewer indications or narrower indications than requested. Further, regulatory agencies may impose safety monitoring, educational requirements or risk evaluation and mitigation strategies, or REMS. Regulatory authorities may also fail to approve the facilities or processes used to manufacture a product candidate or the dosing or delivery methods.

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The regulatory review process may also take significantly longer than expected, which may delay or eliminate any potential revenues from sales of the affected product or product candidate. Target action dates and regulatory timelines may be subject to substantial delays. Although the FDA and EMA have programs to facilitate expedited development and accelerated approval processes, these programs may not result in faster review or approval than conventional procedures and do not assure ultimate approval. In addition, although the FDA granted Breakthrough Therapy designation to each of PADCEV and disitamab vedotin in a specified treatment setting, these Breakthrough Therapy designations do not increase the likelihood that PADCEV or disitamab vedotin will receive marketing approval in the specified settings or in any other settings in a timely manner or at all. Disruptions at the FDA and other agencies due to reduced funding levels, government shutdowns, impacts associated with the COVID-19 pandemic or other factors, may also lead to delays in the regulatory review process. These disruptions may also slow our other interactions with regulatory agencies, which may slow our other product development efforts.

If a product candidate fails to receive regulatory approvals, we will not have the anticipated revenues from that product candidate to fund our operations, and we may not recoup or receive any return on our investment in that product candidate. Similarly, if regulatory authorities do not approve product labeling that is necessary or desirable for the successful commercialization of an approved product, or if they do not approve an application to expand a product’s labeled indications of use or market the product in a new territory, then our anticipated revenue from that product may be adversely affected. Any of these events could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

Even if regulatory approval is achieved, the launch of a new product or of an existing product in a new indication or territory is subject to a number of risks and uncertainties and may not be successful.

Sales of a new product and sales of an existing product in a new indication or territory are subject to significant risks and uncertainties and can be particularly difficult to predict. For example, the commercialization of TIVDAK is at an early stage and may not be successful. In addition to commercialization risks described elsewhere in these "Risk Factors", impacts related to the COVID-19 pandemic, including restrictions on in-person interactions and resulting impacts on our ability to connect with key customers and conduct payor engagements, could limit our and our collaborators' abilities to effectively launch and commercialize a new product or to launch and commercialize an existing product in a new indication or territory. A proposed launch, including the launch of PADCEV and TUKYSA in countries in Europe where they have not yet launched, could also be delayed or impaired due to a variety of factors, including supply constraints, delays in arranging a commercial infrastructure, delays in obtaining or failure to obtain pricing and reimbursement approvals, or other factors. These risks could be heightened by impacts related to the COVID-19 pandemic. Delays or other difficulties due to any of these factors could negatively impact anticipated revenue from the affected product. In addition, prior to TUKYSA, we had no prior experience as an organization launching or commercializing a product outside the U.S. and Canada, which could adversely affect our ability to maximize the commercial potential of TUKYSA. If we and our collaborators are unable to successfully launch and commercialize any newly approved products and/or to successfully launch and commercialize our existing products in new indications or territories, then our business, results of operation, financial condition and growth prospects could be adversely affected.

Reports of adverse events or safety concerns involving our products or product candidates could delay or prevent us from obtaining or maintaining regulatory approvals or could negatively impact sales of our products or the prospects for our product candidates.

Reports of adverse events or safety concerns involving our products and product candidates could result in the limitation, denial or withdrawal of regulatory approval by the FDA or other regulatory authorities for any or all indications, the need to conduct additional trials, implementation of a REMS or the inclusion of unfavorable information in our product labeling and, in turn, could delay or prevent us from commercializing the applicable product or product candidate. There are no assurances that patients receiving our products will not experience serious adverse events, including fatal events, in the future, whether the serious adverse events are disclosed in the prescribing information or are newly reported. Further, there are no assurances that patients receiving our products with co-morbid diseases not previously studied, such as autoimmune diseases, will not experience new or different serious adverse events in the future.

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The prescribing information for each of our products includes warnings and precautions for various toxicities and reactions, including certain fatal reactions. The prescribing information for ADCETRIS also includes a boxed warning related to the risk that JC virus infection resulting in progressive multifocal leukoencephalopathy and death can occur in patients receiving ADCETRIS. The prescribing information for PADCEV also includes a boxed warning related to the risk that severe and fatal cutaneous adverse reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, may occur in patients receiving PADCEV. The prescribing information for TIVDAK also includes a boxed warning related to the risk that ocular toxicity may occur in patients receiving TIVDAK, and the boxed warning includes requirements for ophthalmic exams at baseline, prior to each dose, and as clinically indicated, as well as premedication and eye care. We have updated the prescribing information for our products from time to time in the past, based on reports of adverse events or safety concerns, and we may be required to further update the prescribing information for our products, including boxed warnings, limitations of use, contraindications, warnings and precautions, and adverse reactions, or to implement a REMS in the future. Side effects and toxicities associated with our products, as well as the warnings, precautions and requirements listed in the prescribing information for our products, could affect the willingness of physicians to prescribe, and patients to utilize, our products and thus harm commercial sales of our products. Implementation of a REMS could advantage products that compete with ours or make it more difficult or expensive for us to distribute our products.

Likewise, reports of adverse events or safety concerns involving our products and product candidates could interrupt, delay or halt clinical trials of our products and product candidates, including the post-approval confirmatory studies that regulatory agencies have required us or our collaborators to complete. There have been serious side effects and, in some cases, deaths in clinical trials for our products and product candidates that were deemed to be treatment-related by the investigators in those trials, and additional and/or unexpected side effects may be observed in these or other trials in the future. In addition, in response to prior safety events observed in our clinical trials, including serious side effects and patient deaths, we have in the past, and may in the future, institute additional precautionary safety measures such as dosing caps and delays, enhanced monitoring for side effects, and modified patient inclusion and exclusion criteria. Additional and/or unexpected safety events could be observed in these or other trials that could delay or prevent us from advancing the clinical development of, or obtaining regulatory approvals for, our products and product candidates, could require us to alter the approved labeling of our products, may cause a trial to be redone or terminated, may affect patient recruitment or may affect the ability of enrolled patients to complete a trial. As a result, such safety events could adversely affect our business, results of operations, financial condition and growth prospects.

Clinical trials and product development are expensive, time consuming and uncertain, may take longer than we expect and may not be successful. Our failure to effectively advance our development programs in a timely manner or at all could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

Our long-term success will depend upon the successful development of new products, as well as developing our existing products for new indications. However, only a small number of development programs result in the commercialization of a product. It is possible that none of our product candidates will ever become commercial products and that none of our existing products will obtain regulatory approval in any additional indications or territories. We and our collaborators are currently conducting multiple clinical trials for our products and product candidates, and we plan to commence additional trials in the future. Each of these trials requires the investment of substantial expense and time. However, there can be no assurance that the design or conduct of these trials, or any data collected from them, will be sufficient to support advancement to the next stage of development, any regulatory approvals or commercial viability.

Many of our clinical trials were initiated based on limited data. Encouraging preclinical, preliminary or interim data, and/or positive early-stage clinical trial results do not ensure that full, larger scale, later stage or confirmatory trials will be successful or that regulatory approval will be obtained. For example, despite the positive initial results we and Astellas reported from the dose-escalation cohort and expansion cohort A of the EV-103 trial, we cannot be certain that PADCEV will demonstrate sufficient efficacy or a favorable safety profile in other trials, including the EV-302 trial, or in other cohorts of the EV-103 trial, including cohort K. PADCEV may never be approved for use in any frontline setting or any other additional indications. Similarly, despite the encouraging antitumor activity in initial results from 23 patients in the MOUNTAINEER trial, we cannot be certain that TUKYSA will demonstrate sufficient efficacy or a favorable safety profile in the MOUNTAINEER trial or in other trials. TUKYSA may never be approved for use in the MOUNTAINEER treatment setting or in any other additional indications. Many companies in the pharmaceutical and biotechnology industries, including us, have suffered significant setbacks in late-stage clinical trials after achieving encouraging or positive results in early-stage development. We cannot be certain that we will not face similar setbacks in our ongoing or planned clinical trials, including ongoing pivotal and confirmatory trials.

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There may still be important facts about the safety, efficacy, and risk versus benefit of our products and product candidates, as single agents or in combination with other agents, that are not known to us at this time and that may negatively impact our ability to develop and commercialize them. Safety events or concerns, or negative or inconclusive trial results, could adversely affect the development timeline and the regulatory approval and commercialization prospects for our products and product candidates, or cause us to cease further development of a product or product candidate, any of which may materially and adversely affect our business, results of operations, financial condition and growth prospects. In addition, we may make a strategic decision to discontinue development if, for example, we believe commercialization will be difficult relative to the standard of care or we prefer to prioritize other opportunities in our pipeline. We also face intense competition, and it is possible that a clinical trial may meet its safety and efficacy endpoints but we may choose not to advance the development of a product or product due to changes in the competitive environment.

From time to time, the commencement, continuation and completion of our clinical trials have been subject to delays, and we are likely to experience additional delays in the future. Factors that could lead to the delay, suspension, termination or need to modify clinical trials of our products and product candidates include:

•adverse medical events or side effects, including fatalities, in treated patients or other safety issues or concerns;

•deficiencies in the conduct of the clinical trial, including failure to conduct the clinical trial in accordance with regulatory requirements, Good Clinical Practice, or GCP, or study protocols;

•problems, errors or other deficiencies with respect to data collection, data processing and analysis;

•action by competent authorities to place a clinical hold or partial clinical hold on a trial or compound;

•the time required to determine efficacy may be longer than expected;

•unfavorable scientific results or insufficient data to support safety and effectiveness;

•inadequate supply or deficient quality of the applicable product or product candidate or of other materials necessary to complete the trials;

•inability to reach agreement on acceptable terms with prospective trial sites, the terms of which can be subject to extensive negotiation and may vary significantly among different trial sites;

•delay or failure to obtain institutional review board, or IRB, or ethics committee approval to conduct a clinical trial at a prospective site;

•decisions by competent authorities, IRBs, ethics committees, our collaborators or us, or recommendation by a data monitoring committee, to suspend or terminate a clinical trial for safety issues, futility or any other reason or to demand variations in the protocols or conduct of clinical trials;

•changes in governmental regulations or administrative actions that adversely affect the ability to continue to conduct or to complete a clinical trial;

•budgetary constraints or prohibitively high clinical trial costs;

•difficulties in identifying and enrolling patients who meet trial eligibility criteria;

•lower than anticipated retention rates for patients who have initiated a clinical trial;

•the risks and evolving effects of the COVID-19 pandemic; and

•risks related to the ongoing military conflict between Russia and Ukraine, and sanctions imposed against Russia by the international community.

Additionally, patient enrollment is a function of many factors, including the size of the patient population, the proximity of patients to clinical sites, the eligibility criteria for the trial, the existence of competing clinical trials, perceived side effects and the availability of alternative or new treatments. We have experienced enrollment-related delays in clinical trials in the past, and we will likely continue to experience similar delays in our current and future trials. Many of our future and ongoing clinical trials are being or will be coordinated or conducted with collaborators. If we and these collaborators fail to collaborate effectively, we may experience delays or adverse effects on the commencement, continuation or completion of these trials. In addition, our collaborators have operational control over some of the studies we conduct jointly and we do not have full visibility into these studies run by our collaborators. We also conduct clinical trials in countries outside the U.S., which may subject us to additional expenses, regulatory requirements and potential delays, as well as risks associated with different standards of medical care.

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If a product candidate or a potential new indication fails at any stage of development, or if we or our collaborators otherwise discontinue development of a product candidate or indication for any reason, we will not have the anticipated revenues from that product candidate or indication to fund our operations and we may not recoup or receive any return on our investment in that product candidate or indication. Failure to effectively advance our development programs in a timely manner or at all could have a material adverse effect on our business, results of operations, financial condition and prospects.

The successful commercialization of our products will depend, in part, on the extent to which governmental authorities and health insurers establish adequate coverage and reimbursement levels and pricing policies.

Successful sales of our current and any future approved products will depend, in part, on the extent to which coverage and reimbursement for our products will be available from government and health administration authorities, private health insurers and other third-party payors. To manage healthcare costs, many governments and third-party payors increasingly scrutinize the pricing of new products and require increasing levels of evidence of favorable clinical outcomes and cost-effectiveness before extending coverage. In light of this pricing scrutiny, we cannot be sure that we and our collaborators will achieve and maintain coverage for our products and any product candidates that we or our collaborators commercialize and, if available, that the reimbursement rates will be adequate and grant access to all eligible patients. If we or our collaborators are unable to obtain and maintain coverage and adequate levels of reimbursement for our current and any future approved products that we or our collaborators commercialize, their marketability will be negatively and materially impacted. For example, we cannot be certain that third-party payors will continue to provide coverage and adequate reimbursement for ADCETRIS in the frontline Hodgkin lymphoma indication based on the relative price and perceived benefit of ADCETRIS as compared to alternative treatment options, which may materially harm our ability to maintain or increase sales of ADCETRIS or may otherwise negatively affect future ADCETRIS sales. Similarly, we cannot be certain that third-party payors will provide coverage and adequate reimbursement for PADCEV, TUKYSA or TIVDAK based on their relative price and perceived benefits as compared to alternative treatment options or otherwise, which may materially harm our and our collaborators’ ability to successfully commercialize PADCEV, TUKYSA and TIVDAK in our respective designated territories. In addition, we have also experienced an increase in gross-to-net deductions for ADCETRIS since the beginning of the COVID-19 pandemic, which has been driven by the proportion of ADCETRIS sales subject to discounts through the federal 340B drug discount program, as well as increases in discount rates. We believe that the increase in gross-to-net deductions is, in part, due to a shift in the locations where ADCETRIS is administered. We may further experience additional increases in gross-to-net deductions for ADCETRIS and the rest of our portfolio in the future based on market and site-of-care dynamics.

In many jurisdictions, including many countries in Europe, the proposed pricing for a drug must be approved in an individual country before it may be lawfully marketed, which could delay entry of a product into a market or, if pricing is not approved, may prevent us or our collaborators from selling a product in a country where it has received regulatory approval. In European countries where TUKYSA and PADCEV have obtained regulatory approval, we will seek pricing and reimbursement agreements for TUKYSA, and work with Astellas to seek pricing and reimbursement agreements for PADCEV, in accordance with local timelines. As an organization, we did not have any experience applying for pricing and reimbursement approvals in jurisdictions outside the U.S. and Canada prior to our applications with respect to TUKYSA. Further, authorities in Europe have substantial discretion in the pricing and reimbursement approval process and in determining when or whether coverage will be available for a product in its initial indication or for any additional indications or in additional territories. In addition, in some cases, they may lower the price for a medicine after the price has been established. If we or our collaborators are unable to obtain favorable pricing and reimbursement approvals in the countries that represent significant potential markets, our anticipated revenue from and growth prospects for PADCEV and/or TUKYSA in those regions would be negatively affected.

Eligibility for coverage and reimbursement does not imply that payors will pay for a drug in all cases or at a rate that captures the value delivered to patients, payors and the overall healthcare system; allows for continued investment in innovative treatments for cancer patients; or covers our costs, including research, development, manufacture, sale and distribution. In addition, obtaining and maintaining adequate coverage and reimbursement status is time-consuming and costly. Third-party payors may deny coverage and reimbursement status altogether for a given product, or they may cover the product but establish prices at levels that are too low to enable us to realize an appropriate return on our investment in product development or limit access to select patient populations, reducing revenue potential. Further, in the U.S., there is no uniform policy of coverage and reimbursement among third-party payors. Third-party payors often rely upon Medicare coverage policy and payment limitations in setting their own coverage and reimbursement policies. However, decisions regarding the extent of coverage and amount of reimbursement to be provided is made on a payor-by-payor basis. One payor’s determination to provide coverage for a product does not assure that other payors will also provide coverage for the product. Because the rules and regulations regarding coverage and reimbursement change frequently, in some cases at short notice, even when there is favorable coverage and reimbursement, future changes may occur that adversely impact the favorable status.

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The unavailability or inadequacy of third-party coverage and reimbursement could have a material adverse effect on the market acceptance of our current and any future approved products and the future revenues we may expect to receive from those products. In addition, we are unable to predict what additional legislation or regulation relating to the healthcare industry or third-party coverage and reimbursement may be upheld or enacted in the future, or what effect such legislation or regulation would have on our business. Continuing negative publicity regarding pharmaceutical pricing practices and ongoing governmental and societal scrutiny create significant uncertainty regarding regulation of the healthcare industry and third-party coverage and reimbursement in the U.S. and other jurisdictions. If additional healthcare policies or reforms intended to curb healthcare costs are implemented or if we experience negative publicity with respect to pricing of our products or the pricing of pharmaceutical products generally, the prices that we charge for our current and any future approved products may be limited, and our revenues from sales of our current and any future approved products may be negatively impacted.

The successful commercialization of our products will also depend in part on the acceptance of our products by the medical community, patients and third-party payors.

The degree of market acceptance among patients, physicians, and third-party payors is important to our ability to successfully commercialize our current and any future approved products. The degree of acceptance will depend on a number of factors including the clinical benefits of our products, the effectiveness of our marketing, sales and distribution strategy and operations, the perceived advantages and relative cost, safety and efficacy of alternative treatments, and the acceptance and degree of adoption of our products by institutional treatment pathways and institutional, local, and national clinical guidelines. In the U.S., many oncology practices and healthcare providers rely on the National Comprehensive Cancer Networks® Clinical Practice Guidelines in Oncology or other institutional practice pathways in decisions related to treatment of patients and utilization of medicines. To the extent that our current or any future approved products are not included or positioned favorably in such treatment guidelines and pathways, the full utilization potential of our products may not be reached, which may harm our ability to successfully commercialize our current or any future approved products.

Any failures or setbacks in our ADC development program or our other platform technologies could negatively affect our business and financial position.

ADCETRIS, PADCEV, TIVDAK and our ladiratuzumab vedotin and disitamab vedotin product candidates are all based on antibody-drug conjugate, or ADC, technology, which utilizes proprietary stable linkers and potent cell-killing synthetic agents. Our ADC technology is also the basis of our license agreements with AbbVie Biotechnology Ltd., or AbbVie, Astellas, Genentech, Inc., a member of the Roche Group, or Genentech, and GlaxoSmithKline LLC, or GSK, and our collaboration agreements with Takeda, Astellas, Genmab and Merck. Any failures or setbacks in our ADC development program or with respect to our additional proprietary technologies, including adverse effects resulting from the use of this technology in human clinical trials and/or the imposition of clinical holds on our trials of our product candidates, could have a detrimental impact on the continued commercialization of our products in their current or any potential future approved indications and on our product candidate pipeline, as well as our ability to maintain and/or enter into new corporate collaborations regarding our ADC technology, which would negatively affect our business and financial position.

We face intense competition and rapid technological change, which may result in others discovering, developing or commercializing competing products before or more successfully than we do.

The biotechnology and biopharmaceutical industries are characterized by rapidly advancing technologies and intense competition. Many third parties compete with us in developing various approaches to treating cancer. They include pharmaceutical companies, biotechnology companies, academic institutions and other research organizations. Many of our competitors have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approval and marketing than we do. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

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With respect to ADCETRIS, there are several other FDA approved drugs for its approved indications. Bristol-Myers Squibb’s, or BMS's, nivolumab and Merck’s pembrolizumab are approved for the treatment of certain patients with relapsed or refractory classical Hodgkin lymphoma, and Acrotech Biopharma’s pralatrexate and belinostat are approved for relapsed or refractory systemic anaplastic large cell lymphoma, or sALCL, among other T-cell lymphomas. Celgene's romidepsin is approved for cutaneous T-cell lymphoma. Kyowa Kirin’s mogamulizumab is approved for adult patients with relapsed or refractory mycosis fungoides or Sézary syndrome. The competition ADCETRIS faces from these and other therapies is intensifying. Additionally, Merck conducted a phase 3 clinical trial in relapsed or refractory classical Hodgkin lymphoma comparing pembrolizumab to ADCETRIS. An interim analysis of this clinical trial demonstrated a statistically significant improvement in progression-free survival for pembrolizumab compared with ADCETRIS, resulting in a label expansion to an earlier line of therapy, and we expect increased competition from pembrolizumab in this indication. We are also aware of multiple investigational agents currently being studied that, if successful, may compete with ADCETRIS in the future, such as camidanlumab tesirine being studied in a phase 2 study in relapsed/refractory classical Hodgkin lymphoma. Merck is conducting a phase 2 study in newly diagnosed classical Hodgkin lymphoma. Data have also been presented on several developing technologies, including bispecific antibodies and CAR modified T-cell therapies that may compete with ADCETRIS in the future. Further, there are many competing approaches used in the treatment of patients in ADCETRIS’ approved indications, including autologous hematopoietic stem cell transplant, allogeneic hematopoietic stem cell transplant and chemotherapy, in addition to clinical trials with experimental agents.

With respect to PADCEV, other treatments in pretreated metastatic urothelial cancer include sacituzumab govitecan (a Trop-2-directed antibody and topoisomerase inhibitor conjugate), checkpoint inhibitor monotherapy, generic chemotherapy and, for patients with select FGFR genetic alterations, Janssen’s erdafitinib. Front line metastatic urothelial cancer has traditionally been treated with chemotherapy alone but is evolving to include checkpoint inhibitors for cisplatin-ineligible patients with high PD-L1 expression in addition to patients who are ineligible for platinum therapy. Several trials of investigational agents in combination with chemotherapy or other novel agents are ongoing. Continued development of PD-(L)1 targeted therapies across early stage bladder cancer and in metastatic bladder cancer in frontline combinations with chemotherapy, in frontline maintenance with the recent approval of avelumab, and in pretreated disease, could potentially impact PADCEV usage and enrollment in PADCEV clinical trials.

With respect to TUKYSA, there are multiple marketed products which target HER2, including the antibodies trastuzumab and pertuzumab and the antibody drug conjugate T-DM1. In addition, lapatinib is an EGFR/HER2 oral kinase inhibitor for the treatment of metastatic breast cancer, and neratinib is an irreversible pan-HER kinase inhibitor indicated for extended adjuvant treatment and treatment of metastatic breast cancer in patients who received two or more prior anti-HER2-based regimens. Daiichi Sankyo and AstraZeneca have fam-trastuzumab deruxtecan-nxki which was approved by the FDA for patients who have received two or more prior anti-HER2-based regimens in the metastatic breast cancer setting and in the HER2 positive gastric cancer setting post-trastuzumab-based therapy. The agent was also granted conditional marketing authorization by the EMA for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens. In addition, fam-trastuzumab deruxtecan-nxki is being reviewed by the FDA for use in second line HER2 positive metastatic breast cancer (i.e., in patients who previously received one anti-HER2 based regimen in the metastatic setting) based on the DESTINY-Breast03 trial results. If approved, the sequence of therapies patients receive in this condition is likely to change, with greater fam-trastuzumab deruxtecan-nxki use in second line. This may pose increased competition for TUKYSA, which is approved by the FDA for patients who have received one or more prior anti-HER2-based regimens in the metastatic breast cancer setting, including in patients with brain metastases. MacroGenics has a HER2 targeted, Fc-optimized antibody, margetuximab, which is approved by the FDA for patients who have received at least two previous anti-HER2 regimens. Additionally, Byondis has an antibody drug conjugate, SYD985, and has released results from its pivotal trial in metastatic breast cancer patients treated with multiple anti-HER2-based regimens; approval of SYD985 for this patient population may occur in 2022.

With respect to TIVDAK, in October 2021, Merck’s pembrolizumab was approved in first line in combination with chemotherapy, with or without bevacizumab, for the treatment of recurrent or metastatic cervical cancer whose tumors express PD-L1 and was granted full approval in second line as a monotherapy for recurrent or metastatic cervical cancer patients with disease progression on or after chemotherapy in patients whose tumors express PD-L1. In March 2022, Merck also received a positive opinion from the EU Committee for Medicinal Products for Human Use for pembrolizumab as first line therapy in combination with chemotherapy, with or without bevacizumab for treatment of persistent, recurrent or metastatic cervical cancer whose tumors express PD-L1.We are also aware of other companies that currently have products in development for the treatment of late-stage cervical cancer which could be competitive with TIVDAK, including Agenus, BMS, Iovance Biotherapeutics, Merck, Regeneron Pharmaceuticals, Sanofi-Aventis and Roche. Cemiplimab is being reviewed in several countries outside the U.S. for the treatment of patients with recurrent or metastatic cervical cancer following progression on platinum-based chemotherapy. A supplemental Biologics License Application for cemiplimab was withdrawn in the U.S. in January 2022. In March 2022, Sanofi received Canadian approval for cemiplimab for the treatment of patients with cervical cancer who have progressed on or after prior platinum-based chemotherapy.

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Many other pharmaceutical and biotechnology companies are developing and/or marketing therapies for the same types of cancer that our product candidates are designed and being developed to treat. In addition, we are aware of a number of other companies that have ADC and other technologies that may be competitive with ours. We are also aware of a number of companies developing monoclonal antibodies directed at the same antigen targets or for the treatment of the same diseases as our product candidates. In addition, our ADC collaborators may develop compounds utilizing our technology that may compete with product candidates that we are developing.

The risk of biosimilar or generic challenges has also been increasing in our industry. In the U.S. and the EU, after a period of exclusivity for an innovator’s approved biological product or branded drug has passed, there are abbreviated pathways for approval of biosimilar products or generic drugs. In addition, it is not possible to predict changes in law that might reduce regulatory exclusivity. As a result, and due to uncertainties regarding patent protection, it is not possible to predict the length of market exclusivity for any particular product with certainty based solely on the expiration of the relevant patent(s) or the current forms of regulatory exclusivity. Absent patent protection or regulatory exclusivity for our products, it is possible, both in the United States and elsewhere, that biosimilar, interchangeable or generic versions of those products may be approved and marketed, which would likely result in substantial and rapid reductions in revenues from sales of those products.

It is also possible that our competitors will succeed in developing technologies that are more effective than our products and product candidates or that would render our technology obsolete or noncompetitive, or will succeed in developing biosimilar, interchangeable or generic products for our products and product candidates. We anticipate that we will continue to face increasing competition in the future as new companies enter our market and scientific developments surrounding biosimilars and other cancer therapies continue to accelerate. We cannot predict to what extent the entry of biosimilars or other competing products will impact potential future sales of our products and product candidates.

Risks Related to Regulatory Oversight, and Other Legal Compliance Matters

Our products and any future approved products remain subject to extensive ongoing regulatory obligations and oversight, including post-approval requirements, that could result in penalties and significant additional expense and could negatively impact our and our collaborators’ ability to commercialize our current and any future approved products.

Any product that has received regulatory approval remains subject to extensive ongoing obligations and continued review from applicable regulatory agencies. These obligations include, among other things, drug safety reporting and surveillance, submission of other post-marketing information and reports, pre-clearance of certain promotional materials, manufacturing processes and practices, product labeling, confirmatory or post-approval clinical research, import and export requirements and record keeping. These obligations may result in significant expense and limit our and our collaborators’ ability to commercialize our current and any future approved products. Any violation of ongoing regulatory obligations could result in restrictions on the applicable product, including the withdrawal of the applicable product from the market.

If FDA approval is granted via the accelerated approval pathway or a product receives conditional marketing authorization from another comparable regulatory agency, we and our collaborators may be required to conduct a post-marketing confirmatory trial in support of full approval and to comply with other additional requirements. For example, in connection with ADCETRIS’s conditional marketing authorization in relapsed Hodgkin lymphoma, relapsed cutaneous T-cell lymphoma, and both relapsed and frontline sALCL in the EU, Takeda is subject to certain post-approval requirements, including the requirement to conduct clinical trials to confirm clinical benefit. The FDA’s accelerated approval of TIVDAK also included a requirement for a confirmatory trial. An unsuccessful post-marketing study or failure to complete such a study with due diligence could result in the withdrawal of marketing approval. Post-marketing studies may also suggest unfavorable safety information that could require us to update the product’s prescribing information or limit or prevent the product’s widespread use. In addition, the labeling, advertising and promotion of products that have received accelerated approval from the FDA, including TIVDAK, are subject to additional regulatory requirements, which entail significant expense and could negatively impact the product’s commercialization.

Regulatory authorities may also impose additional post-marketing commitments, including requirements for companion diagnostics. For example, the FDA’s approval of ADCETRIS in the frontline peripheral T-cell lymphoma indication included a post-marketing commitment to develop an in-vitro diagnostic device for the selection of patients with CD30-expressing PTCL, not including SALCL, for treatment with ADCETRIS in this indication. We and Takeda have a collaboration with Ventana Medical Systems, Inc., or Ventana, under which Ventana is working to develop such a diagnostic device.

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We and the manufacturers of our current and any future approved products are also required, or will be required, to comply with current Good Manufacturing Practices, or cGMP, regulations, which include requirements relating to quality control and quality assurance as well as the corresponding maintenance of records and documentation. Further, regulatory agencies must approve these manufacturing facilities before they can be used to manufacture our products and product candidates, and these facilities are subject to ongoing regulatory inspections. In addition, any approved product, its manufacturer and the manufacturer’s facilities are subject to continual regulatory review and inspections, including periodic unannounced inspections. Failure to comply with applicable FDA and other regulatory requirements may subject us to administrative or judicially imposed sanctions and other consequences, including:

•issuance of Form FDA 483 notices or Warning Letters by the FDA or other regulatory agencies;

•imposition of fines and other civil penalties;

•criminal prosecutions;

•injunctions, suspensions or revocations of regulatory approvals;

•suspension of any ongoing clinical trials;

•total or partial suspension of manufacturing;

•delays in regulatory approvals and commercialization;

•refusal by the FDA to approve pending applications or supplements to approved applications submitted by us;

•refusals to permit drugs to be imported into or exported from the U.S.;

•restrictions on operations, including costly new manufacturing requirements;

•product recalls or seizures or withdrawal of the affected product from the market; and

•reputational harm.

The policies of the FDA and other regulatory agencies may change and additional laws and regulations may be enacted that could prevent or delay regulatory approval of our product candidates or of our products in any additional indications or territories, or further restrict or regulate post-approval activities. Any problems with a product or any violation of ongoing regulatory obligations could result in restrictions on the applicable product, including the withdrawal of the applicable product from the market. If we are not able to maintain regulatory compliance, we or our collaborators might not be permitted to commercialize our current or any future approved products and our business would suffer.

Healthcare law and policy changes may negatively impact our business, including by decreasing the prices that we and our collaborators receive for our products.

In recent years, there have been a number of legislative and regulatory actions and executive orders that have made reforms to the U.S. healthcare system. The implementation of certain of these policy changes has decreased our revenues and increased our costs, and federal and state legislatures, governments in countries outside the U.S., health agencies and third-party payors continue to focus on containing the cost of healthcare. Further legislative and regulatory changes, and increasing pressure from social sources, are likely to further influence the manner in which our products are priced, reimbursed, prescribed and purchased. Such additional reforms could result in further reductions in coverage and levels of reimbursement for our products, expansion of U.S. government rebate and discount programs, increases in the rebates and discounts payable under these programs, requests for additional or supplemental rebates, and additional downward pressure on the prices that we and our collaborators receive for our products.

The federal government has implemented reforms to government healthcare programs in the U.S., including changes to the methods for, and amounts of, Medicare reimbursement and changes to the Medicaid Drug Rebate Program. For example, on March 11, 2021, President Biden signed the American Rescue Plan Act of 2021 into law, which eliminates the statutory Medicaid drug rebate cap, currently set at 100% of a drug’s average manufacturer price, for single source and innovator multiple source drugs, beginning January 1, 2024. On November 15, 2021, President Biden signed the Infrastructure Investment and Jobs Act, which included changes to the Medicare Part B program requiring rebates for some discarded drug products that are expected to increase future rebates for ADCETRIS, PADCEV and TIVDAK with a target implementation date of the first quarter of 2023. The Biden administration also recently announced an Executive Order that includes initiatives to support the implementation of Canadian drug importation and reduce drug prices. In response to President Biden’s Executive Order, on September 9, 2021, the U.S. Department of Health and Human Services released a Comprehensive Plan for Addressing High Drug Prices that outlines principles for drug pricing reform and sets out a variety of potential legislative policies that Congress could pursue to advance these principles. No legislation or administrative actions have been finalized to implement these principles. In addition, Congress is considering drug pricing as part of other healthcare reform initiatives.

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Some states are also considering legislation, or have passed laws, that would control the prices and coverage and reimbursement levels of drugs, including laws to allow importation of pharmaceutical products from lower cost jurisdictions outside the U.S. and laws intended to impose price controls on state drug purchases.

In addition, governments in countries outside the U.S. control the costs of pharmaceuticals. Many European countries and Canada have established pricing and reimbursement policies that contain costs by referencing the price of the same or similar products in other countries. In these instances, if coverage or the level of reimbursement is reduced, limited or eliminated in one or more countries, we may be unable to obtain or maintain anticipated pricing or reimbursement in other countries or in new markets. This may create the opportunity for third-party cross-border trade or may influence our decision whether to sell a product in one or more countries, thus adversely affecting our geographic expansion plans.

It is also possible that governments may take additional action to reform the healthcare system in response to the evolving effects of the COVID-19 pandemic.

We cannot assure you as to the ultimate content, timing, or effect of future healthcare law and policy changes, nor is it possible at this time to estimate the impact of any such potential changes; however, such changes or the ultimate impact of changes could materially and adversely affect our revenue or sales of our current and or potential future products, as well as those of our collaborators.

We are subject to various state, federal and international laws and regulations, including healthcare laws and regulations, that may impact our business and could subject us to significant fines and penalties or other negative consequences.

Our operations may be directly or indirectly subject to various healthcare laws, including, without limitation, the federal Anti-Kickback Statute, federal civil and criminal false claims laws, regulations prohibiting off-label promotions and federal transparency requirements. These laws may impact, among other things, the sales, marketing and education programs for our products and any future approved products. In addition, the number and complexity of healthcare laws and regulations applicable to our business continue to increase.

The federal Anti-Kickback Statute prohibits, among other things, knowingly and willingly soliciting, offering, receiving or providing remuneration, directly or indirectly, in exchange for or to induce either the referral of an individual, or the furnishing or arranging for a good or service, for which payment may be made, in whole or in part, under a federal healthcare program such as the Medicare and Medicaid programs. Although there are a number of statutory exceptions and regulatory safe harbors protecting some common activities from prosecution, the exceptions and safe harbors are drawn narrowly, and practices that involve remuneration not intended to induce prescribing, purchases or recommendations may be subject to scrutiny if they do not qualify for an exception or safe harbor. In addition, a criminal conviction for violation of the federal Anti-Kickback Statute requires mandatory exclusion from participation in federal healthcare programs.

The federal civil and criminal false claims laws, including the civil False Claims Act, prohibit, among other things, persons or entities from knowingly presenting, or causing to be presented, a false claim to, or the knowing use of false statements to obtain payment from or approval by, the federal government, including the Medicare and Medicaid programs, or knowingly making, using, or causing to be made or used a false record or statement material to a false or fraudulent claim or to avoid, decrease, or conceal an obligation to pay money to the federal government. Many pharmaceutical and other healthcare companies have been investigated and have reached substantial financial settlements with the federal government under the civil False Claims Act for a variety of alleged improper marketing, promotion or other activities.

The FDA and other governmental authorities also actively investigate allegations of off-label promotion activities in order to enforce regulations prohibiting these types of activities. In recent years, private whistleblowers have also pursued False Claims Act cases against a number of pharmaceutical companies for causing false claims to be submitted as a result of off-label promotion. If we are found to have promoted an approved product for off-label uses, we may be subject to significant liability, including significant civil and administrative financial penalties and other remedies as well as criminal penalties and other sanctions. Even when a company is not determined to have engaged in off-label promotion, the allegation from government authorities or market participants that a company has engaged in such activities could have a significant impact on the company’s sales, business and financial condition. The U.S. government has also required companies to enter into complex corporate integrity agreements, deferred prosecution agreements and/or non-prosecution agreements that impose significant reporting and other burdens on the affected companies.

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The federal transparency requirements under the Physician Payments Sunshine Act require certain manufacturers of drugs, devices, biologics and medical supplies for which payment is available under Medicare, Medicaid, or the Children’s Health Insurance Program to annually report information related to certain payments or other transfers of value to physicians (defined to include doctors, dentists, optometrists, podiatrists and chiropractors), other healthcare professionals (such as physician assistants and nurse practitioners), and teaching hospitals, or to entities or individuals at the request of, or designated on behalf of, the physicians and teaching hospitals, and to report annually certain ownership and investment interests held by physicians and their immediate family members. Failure to submit timely, accurately and completely the required information for all payments, transfers of value and ownership or investment interests may result in civil monetary penalties of up to an aggregate of $150,000 per year plus up to an aggregate of $1 million per year for “knowing failures,” as adjusted for inflation.

In addition, there has been increased scrutiny of company-sponsored patient assistance programs, including co-pay assistance programs, and donations to third-party charities that provide such assistance. There has also been enhanced scrutiny by governments of reimbursement support offerings, clinical education programs and promotional speaker programs. If we or our vendors are deemed to fail to comply with laws or regulations in the operation of these programs, we could be subject to damages, fines, penalties or other criminal, civil or administrative sanctions or enforcement actions. Further, in connection with civil settlements related to these laws and regulations, the U.S. government has and may in the future require companies to enter into complex corporate integrity agreements that impost significant reporting and other requirements.

Other healthcare laws and regulations that may affect our ability to operate include, among others, the federal civil monetary penalties statute and the healthcare fraud provisions of the federal Health Insurance Portability and Accountability Act, or HIPAA. In addition, many states and jurisdictions outside the U.S. have similar laws and regulations, such as anti-kickback, anti-bribery and corruption, false claims and transparency, to which we are currently and/or may in the future, be subject. Additional information about these requirements is provided under “Government Regulation – Healthcare Regulation” in our Annual Report on Form 10-K for the year ended December 31, 2021.

We are also subject to numerous other laws and regulations that while not specific to the healthcare industry, do apply to the healthcare industry in important ways. For example, we are subject to antitrust regulations with respect to interactions with other participants in the markets we currently serve or may serve in the future. These antitrust laws are vigorously enforced in the U.S. and in other jurisdictions in which we operate.

In an effort to comply with applicable laws and regulations, we have implemented a compliance program designed to actively identify, prevent and mitigate risk by implementing policies and systems and promoting a culture of compliance. We also actively work to revise and evolve our compliance program in an effort to keep pace with evolving compliance risks and the growing scale of our business. However, we cannot guarantee that our compliance program will be sufficient or effective, that we will be able to integrate the operations of newly formed affiliates or acquired businesses into our compliance program effectively or on a timely basis, that our employees will comply with our policies, that our employees will notify us of any violation of our policies, that we will have the ability to take appropriate and timely corrective action in response to any such violation, or that we will make decisions and take actions that will limit or avoid liability for whistleblower claims or actions by governmental authorities. If we are found to be in violation of any of the laws and regulations described above or other applicable laws, we may be subject to penalties, including significant civil, criminal and administrative penalties, damages, fines, disgorgement, contractual damages, reputational harm, administrative burdens, imprisonment, diminished profits and future earnings, exclusion from government healthcare reimbursement programs, additional reporting requirements and oversight if we become subject to a corporate integrity agreement or similar agreement to resolve allegations of non-compliance with these laws, and/or the curtailment or restructuring of our operations. Any of these outcomes could have a material adverse effect on our business, results of operations, financial condition and growth prospects. Regardless of whether we have complied with the law, a government investigation could negatively impact our business practices, harm our reputation, divert the attention of management and increase our expenses. Moreover, achieving and sustaining compliance with applicable federal, state and healthcare laws outside the U.S. is costly and time-consuming for our management.

We are subject to stringent and changing obligations related to data privacy and information security. Our actual or perceived failure to comply with such obligations could lead to governmental investigations or actions, litigation, fines and penalties, a disruption of our business operations, reputational harm and other adverse business impacts.

We are subject to numerous privacy and data protection laws and regulations governing personal information, including healthcare information. In addition, the legislative and regulatory landscape for privacy and data protection continues to evolve.

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In the United States, federal, state, and local governments have enacted numerous data privacy and security laws, including data breach notification laws, personal data privacy laws, and consumer protection laws. The laws are not consistent, and states frequently amend existing laws, requiring attention to constantly changing regulatory requirements. For example, the California Consumer Privacy Act, or CCPA, became effective on January 1, 2020, and the California Privacy Rights Act, or CPRA, will take effect in January 2023 (with a look back for certain rights to January 2022). The CPRA will significantly modify the CCPA, including by expanding consumers’ rights with respect to certain sensitive personal information. We may also be subject to additional U.S. privacy regulations in the future, including the Virginia Consumer Data Protection Act and the Colorado Privacy Act, both of which become effective in 2023. In addition, at the federal level, HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act, and its implementing regulations impose additional obligations on certain types of individuals and entities with respect to the security, privacy and transmission of individually identifiable health information.

EU member countries and other jurisdictions, including Switzerland, the United Kingdom, or the U.K., and Canada, have also adopted data protection laws and regulations which impose significant compliance obligations. For example, the EU’s General Data Protection Regulation, or GDPR, imposes a range of requirements relating to the collection, use, handling and protection of personal data. Violations of the GDPR can result in significant penalties, including potential fines of up to €20 million or 4% of the annual global revenues of the non-compliant company, whichever is greater. The GDPR has increased our responsibility and potential liability in relation to all types of personal data that we process, including clinical trial data and employee information. In addition, local data protection authorities can have different interpretations of the GDPR, leading to compliance challenges as a result of potential inconsistencies amongst various EU member states.

Among other requirements, the GDPR regulates transfers of personal data to countries that have not been found to provide adequate protection to such personal data, including the U.S. This includes transfers between us and our subsidiaries. In July 2020, the Court of Justice of the EU, or the CJEU, invalidated one of the primary safeguards enabling U.S. companies to import personal information from Europe, the EU-U.S. Privacy Shield. The same decision also raised questions about whether one of the primary alternatives to the EU-U.S. Privacy Shield, namely, the EC’s Standard Contractual Clauses, or SCCs, provide sufficient protection for personal data transfers without analyzing each transfer and implementing supplementary measures to protect the data. As a result of the CJEU’s decision, the EC issued new SCCs in June 2021 that repeal and replace the previous clauses. Companies relying on the SCCs for transfers have until December 2022 to implement the new clauses. Following recommendations from the European Data Protection Board, we are reviewing personal data transfers from the EU and adding the new SCCs and supplementary measures, when required. Since local data protection authorities can interpret GDPR and the CJEU’s decision differently, there is no definitive set of controls that can ensure GDPR compliance across our business operations. In addition, authorities in Switzerland and the U.K., whose data protection laws are similar to those of the EU, also invalidated the use of privacy shields. Additional compliance efforts may be needed to respond to evolving regulatory guidance. If our compliance solutions are found to be insufficient, we could face substantial fines under European data protection laws as well as injunctions against processing and/or transferring personal information from Europe. The inability to import personal information from Europe could restrict our clinical trial activities in Europe, limit our ability to collaborate with contract research organizations, service providers, contractors and other companies subject to European data protection laws, interfere with our ability to hire employees in Europe and require us to increase our data processing capabilities in Europe at significant expense.

In addition, we may be subject to other foreign data privacy and security laws. For example, China’s Personal Information Protection Law, or PIPL, which took effect in November 2021, imposes various requirements related to personal information processing, similar to the GDPR and CCPA. In particular, the PIPL sets out personal information localization requirements, along with rules regarding the transfer of personal information outside of China. Such transfers may require assessment and/or approval by China’s Cyberspace Administration, certification by professional institutions or entering into contracts with and supervising overseas recipients. Violations of the PIPL may lead to an administrative fine of up to RMB 50 million or 5% of turnover in the last year.

Any failure or alleged failure to comply with legal or contractual obligations, policies and industry standards relating to personal information, and any incident resulting in the unauthorized access to, or acquisition, release or transfer of, personal information, may result in governmental investigations or enforcement actions, litigation, fines, penalties, damage to our reputation and other adverse consequences. In addition, we expect that laws, regulations, policies and industry standards relating to privacy and data protection will continue to evolve. These changes may require us to modify our practices and may increase our costs of doing business. In addition, privacy advocates and industry groups have regularly proposed, and may propose in the future, self-regulatory standards that may legally or contractually apply to us. If we fail to follow these standards, even if no personal information is compromised, we may incur significant fines or experience a significant increase in costs.

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Product liability and product recalls could harm our business, and we may not be able to obtain adequate insurance to protect us against product liability losses.

The testing, manufacturing, marketing, and sale of products and product candidates expose us to product liability claims. As a result, it is possible that we may be named as a defendant in product liability suits that may allege that drug products we manufactured for BMS resulted in injury to patients. While we have obtained product liability insurance, it may not provide adequate coverage against all potential liabilities. In addition, we may not be able to maintain insurance coverage on acceptable terms or at all. If a product liability claim or series of claims is brought against us, we may experience substantial financial losses, including uninsured liabilities or liabilities in excess of insured amounts, and may be required to limit further development and commercialization of our products, either of which could have a material adverse effect on our business, results of operations, financial condition and growth prospects. Additionally, product liability claims, regardless of their merits, could be costly, could divert management’s attention and could adversely affect our reputation and the demand for our products.

Product recalls may be issued at our discretion, or at the discretion of government agencies and other entities that have regulatory authority for pharmaceutical sales. Any recall of our products could materially adversely affect our business by rendering us unable to sell our products for some time and by adversely affecting our reputation.

Our operations involve hazardous materials and are subject to environmental, health and safety laws and regulations.

We are subject to environmental, health and safety laws and regulations, including those governing the use and disposal of hazardous materials, and we spend considerable time complying with such laws and regulations. Our business activities involve the controlled use of hazardous materials, and although we take precautions to prevent accidental contamination or injury from these materials, we cannot completely eliminate the risk of using these materials. In this regard, with respect to our manufacturing facility, we may incur substantial costs to comply with environmental laws and regulations and may become subject to the risk of accidental contamination or injury from the use of hazardous materials in our manufacturing process. It is also possible that our manufacturing facility may expose us to environmental liabilities associated with historical site conditions that we are not currently aware of and did not cause. Some environmental laws impose liability for contamination on current owners or operators of affected sites, regardless of fault. In the event of an accident or environmental discharge, or new or previously unknown contamination is discovered or new cleanup obligations are otherwise imposed in connection with any of our currently or previously owned or operated facilities, we may be held liable for remediation obligations, damages or fines, which may exceed our insurance coverage and materially harm our business, financial condition and results of operations. Additional federal, state and local laws and regulations affecting our operations may be adopted in the future. We may incur substantial costs to comply with, and substantial fines or penalties if we violate, any of these laws or regulations.

Risks Related to Our Reliance on Third Parties

Our collaborators and licensees may not perform as expected, which may negatively affect our ability to develop and commercialize our products and product candidates and/or generate revenues through technology licensing, and may otherwise negatively affect our business.

We have established collaborations with third parties to develop and market each of our products and some of our current and potential future product candidates. These include our collaborations with Takeda for ADCETRIS, with Astellas for PADCEV, with Merck for TUKYSA and with Genmab for TIVDAK. We also have established clinical trial collaborations to develop certain of our products or product candidates in combination with the products or product candidates of third parties. Our dependence on these collaboration and licensing arrangements subjects us to a number of risks, including:

•we are not able to control the amount or timing of resources our collaborators and licensees devote to the development or commercialization of our programs, products or product candidates;

•the interests of our collaborators may not always be aligned with our interests, and such parties may not pursue regulatory approvals or market a product in the same manner or to the same extent that we would, which could adversely affect our revenue, or may adopt tax strategies that could have an adverse effect on our business, results of operations or financial condition;

•with respect to products or product candidates under joint control, we may encounter challenges in joint decision making and joint execution, including with respect to any joint development or commercialization plans or co-promotion activities, which may delay or otherwise harm the research, development, launch or commercialization of the applicable products and product candidates;

•disputes may arise between us and our collaborators or licensees, including with respect to the achievement and payment of milestones or ownership of rights to technology developed, that could result in litigation or arbitration;

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•any failure on the part of our collaborators to comply with applicable laws, including tax laws, regulatory requirements and/or applicable contractual obligations or to fulfill any responsibilities they may have to protect and enforce any intellectual property rights underlying our products could have an adverse effect on our revenue as well as involve us in possible legal proceedings;

•any improper conduct or actions on the part of our collaborators, licensees or other third parties could subject us to civil or criminal investigations and monetary penalties and injunctions, impact the accuracy and timing of our financial reporting and/or adversely impact our ability to conduct business, our operating results and our reputation;

•business combinations or significant changes in a collaborator’s business strategy may adversely affect such party’s willingness or ability to complete its obligations under any arrangement;

•a collaborator could independently move forward with competing products, therapeutic approaches or technologies, either independently or in collaboration with others, including with our competitors; and

•our collaboration agreements may be terminated, breached or allowed to expire, or our collaborators may reduce the scope of our agreements with them.

If our collaborative and license arrangements are not successful, then our ability to advance the development and commercialization of the applicable products and product candidates, or to otherwise generate revenue from these arrangements, will be adversely affected, and our business and business prospects may be materially harmed. If any of our collaborators terminates our collaboration or opts out of their obligations, we may have to engage another collaborator, or we may have to complete the development process and undertake commercializing the applicable product or product candidate in our collaborator’s current territories ourselves. This could significantly disrupt or delay the development and commercialization of the applicable product or product candidate and substantially increase our costs. Any of these events could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

A substantial portion of our revenue results from payments made under agreements with our collaborators. The loss of any of our collaborators, changes in product development or business strategies of our collaborators, or the failure of our collaborators to perform their obligations under their agreements with us for any reason, including paying license or technology fees, milestone payments, royalties or reimbursements, could have a material adverse effect on our business, results of operations, financial condition and growth prospects. Payments under our existing and potential future collaboration agreements are also subject to significant fluctuations in both timing and amount, which could cause our revenue to fall below the expectations of securities analysts and investors and cause a decrease in our stock price.

In addition to collaboration agreements, we also have ADC license agreements that allow our licensees to use our proprietary ADC technology. Our ADC licensees conduct all research, product development, manufacturing and commercialization of any product candidates under these agreements. Any delay or termination of the development and commercialization of a licensed product or product candidate by the licensee could adversely affect our business, results of operations, financial condition and growth prospects by reducing or eliminating the potential for us to receive applicable milestones and royalties.

We currently rely on third-party manufacturers and other third parties for production of our drug products, and our dependence on these third parties may impair the continued development and commercialization of our products and product candidates.

We own a biologics manufacturing facility located in Bothell, Washington, which we use to support our clinical supply needs, and we recently invested in the facility infrastructure to enable it to potentially support some of our commercial supply needs in the future. We have also signed a lease to a new facility currently being constructed in Everett, Washington, which will be used for future biologics manufacturing capability. We have made and plan to continue to make significant investments in these facilities with no assurance that these investments will be recouped. We may experience cost overruns, delays or other difficulties in construction, obtaining regulatory approvals and permits or in otherwise bringing these manufacturing facilities online. In addition, we rely and expect to continue to rely on collaborators, contract manufacturers and other third parties to produce and store sufficient quantities of drug product for both our clinical and commercial programs. In some cases, we rely on contract manufacturers and other third parties that are single-source suppliers to complete steps in the manufacturing process. If any of the parties in our supply chain cease or interrupt production or otherwise fail to deliver materials, products or services on a timely basis, with sufficient quality, and at commercially reasonable prices, and we fail to find replacements or to develop our own manufacturing capabilities, we may bear costly losses or be required to delay or suspend clinical trials or otherwise delay or discontinue development, production and sale of our products. As a result, our business, results of operations, financial condition and growth prospects could be materially and adversely affected.

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There are a limited number of facilities in which each of our products and product candidates can be produced. Any interruption of the operation of those facilities, due to equipment malfunction or failure, damage to the facility, natural disasters, regulatory actions, contractual disputes or other events, could result in delays, cancellation of shipments, loss of product in the manufacturing process, or a shortfall in supply. Further, we and our collaborators depend on outside vendors for the supply of raw materials used to produce our products and product candidates. If these suppliers were to cease production or otherwise fail to supply quality raw materials and we or our collaborators were unable to contract with alternative suppliers for these raw materials on acceptable terms, our ability to have our products manufactured to meet clinical and commercial requirements would be adversely affected. In an effort to increase the availability of needed medical and other supplies and products in connection with the COVID-19 pandemic, we and our suppliers may elect to, or governments may require us or our suppliers to, allocate raw materials used in manufacturing or manufacturing capacity (for example pursuant to the U.S. Defense Production Act) in a way that adversely affects our ability to have our products manufactured to meet clinical and commercial requirements. In addition, if any of the parties in our supply chain are adversely impacted by the evolving effects of the COVID-19 pandemic, such as staffing shortages, productions slowdowns and/or disruptions in delivery systems, there could be disruptions and delays in the manufacturing and supply of our products and product candidates.

While we believe that the existing supplies of our products and our and our collaborators’ contract manufacturing relationships will be sufficient to accommodate current clinical and commercial needs, we or our collaborators may need to obtain additional manufacturing arrangements or increase manufacturing capability to meet potential future commercial needs, which could require additional capital investment or cause delays. We cannot assure you that we can enter into additional manufacturing arrangements on commercially reasonable terms or at all. Forecasting demand for a new product or for a newly-approved territory or indication for an existing product can be challenging. If demand for a product exceeds our estimates or if our commercial manufacturers are unable or unwilling to increase production capacity commensurate with demand, our commercialization of the affected product could be negatively impacted by short-term product supply challenges. Supply challenges would adversely impact our revenues and could negatively affect our relationships with patients and healthcare professionals. In addition, any failures or delays in manufacturing adequate product supplies and in putting in place or expanding our manufacturing and supply infrastructure could delay or impede our and collaborators’ ability to launch and commercialize our products, including PADCEV and TUKYSA, in additional markets where they have obtained regulatory approval.

In order to obtain regulatory approval of any product candidate or regulatory approval of any product in a new jurisdiction, the suppliers for that product or product candidate must obtain approval to manufacture and supply product. In addition, the facilities utilized to manufacture the product or product candidate will be subject to pre-approval regulatory inspections. Any delay or failure in generating the chemistry, manufacturing and control data required in connection with any application for regulatory approval, or challenges in the regulatory inspection process, could negatively impact our ability to meet our anticipated regulatory submission dates, delay any approval decisions and/or negatively affect our ability to obtain regulatory approval at all. Any failure of us, our collaborators or a manufacturer to obtain approval to manufacture and supply product in a jurisdiction, or to obtain and distribute adequate supplies of the product, on a timely basis or in accordance with applicable specifications and local requirements could negatively impact our ability to successfully launch and commercialize the applicable product in that jurisdiction and to generate sales of that product at the levels we expect. We or our collaborators may also encounter difficulties in meeting the regulatory requirements applicable to the manufacturing process for these agents, in managing the additional complexity of manufacturing for a number of markets outside the U.S. or in responding to changes in the amount or timing of supply needs. Any failures or delays in meeting these requirements could substantially delay or impede our ability to obtain regulatory approvals for and to market these agents, which could negatively impact our operating results and adversely affect our business.

We are dependent upon a small number of distributors for a significant portion of our net sales, and the loss of, or significant reduction or cancellation in sales to, any one of these distributors could adversely affect our revenues and increase our costs.

We sell ADCETRIS, PADCEV and TIVDAK through a limited number of specialty distributors. Healthcare providers order ADCETRIS, PADCEV and TIVDAK through these distributors. We receive orders from distributors and generally ship product directly to the healthcare provider. We sell TUKYSA through a distribution network of specialty pharmacies, integrated delivery network hospitals and practices that dispense in the office. These distributors and distribution network partners do not set or determine demand for our products; however, our ability to effectively commercialize our products will depend, in part, on their performance. If we lost a major distributor or partner, revenue during any period of disruption could suffer and we might incur additional costs. In addition, business disruptions arising from the COVID-19 pandemic could negatively affect the ability of some of our distributors or distribution network partners to pay amounts owed to us in a timely manner or at all.

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We are dependent on third parties such as contract research organizations, medical institutions and clinical investigators to assist with the design, review, management and conduct of our clinical trials and other activities.

We also depend on third parties such as contract research organizations, medical institutions and clinical investigators to assist with the design, review, management and conduct of our clinical trials and other activities. Our reliance on these third parties reduces our control over these activities but does not relieve us of our responsibilities. For example, we remain responsible for ensuring that each of our clinical trials is conducted in accordance with regulatory requirements, GCP and study protocols. To the extent these third parties fail to successfully carry out their contractual duties or meet expected deadlines, our clinical trials and regulatory filings may be negatively impacted including possible impacts to data, results, or conclusions, increased costs, and delays to regulatory timelines, which may harm our reputation and business.

Risks Related to Intellectual Property and Litigation

If we are unable to enforce our intellectual property rights or if we fail to sustain and further procure additional intellectual property rights, we may not be able to successfully commercialize our products or any future products and competitors may be able to develop competing therapies.

Our success depends, in part, on obtaining and maintaining patent protection and successfully enforcing these patents and defending them against third-party challenges in the U.S. and other countries. We own multiple U.S. and foreign patents and pending patent applications for our technologies. We also have rights to issued U.S. patents, patent applications, and their foreign counterparts, relating to our monoclonal antibody, linker and drug-based technologies. Our rights to these patents and patent applications are derived in part from worldwide licenses from third parties.

The standards that the U.S. Patent and Trademark Office, or USPTO, and patent offices in other countries use to grant patents are not always applied predictably or uniformly and can change. Consequently, our pending patent applications may not be allowed and, if allowed, may not contain the type and extent of patent claims that will be adequate to conduct our business as planned. Additionally, patents may have a shorter patent term than expected or may not contain claims that will permit us to stop competitors from using our technology or similar technology or from copying our products. Similarly, the standards that courts use to interpret patents are not always applied predictably or uniformly and may evolve, particularly as new technologies develop. For example, the U.S. Federal Circuit Court of Appeals and the U.S. Supreme Court have modified some legal standards applied by the USPTO in examination of U.S. patent applications, which may decrease the likelihood that we will be able to obtain patents and may increase the likelihood of challenges to patents we obtain or license. These changes and any future changes to the patent system in the U.S. or in other countries could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business, results of operations, financial condition and growth prospects. In addition, changes to patent laws may be applied retroactively to affect the validity, enforceability, or term of our patents. Patent protection outside the U.S. is particularly uncertain and costly. The laws of some countries may not protect our intellectual property rights to the same extent as U.S. laws, and many companies in our industry have encountered significant difficulties in protecting and defending such rights in these jurisdictions.

We rely on external agents to perform certain activities to maintain our patents. Although we carefully select and oversee these agents, the failure of an agent to properly perform these maintenance activities, whether through mistake or otherwise, could adversely affect our intellectual property rights. Additionally, if we do not control all of the intellectual property rights in-licensed to us with respect to a drug candidate and the entity that controls the intellectual property rights does not adequately protect those rights, our rights may be impaired, which may impact our ability to develop, market and commercialize the in-licensed drug candidate.

We rely on trade secrets and other proprietary information where we believe patent protection is not appropriate or obtainable. However, trade secrets and other proprietary information are difficult to protect. We have taken measures to protect our unpatented trade secrets and know-how, including the use of confidentiality and assignment of inventions agreements with our employees, consultants and certain contractors. It is possible, however, that these persons may breach the agreements or that our competitors may independently develop or otherwise discover our trade secrets or other proprietary information. Our research collaborators may also publish confidential data or other restricted information to which we have rights. If we cannot maintain the confidentiality of our technology and other confidential information in connection with our collaborations, then our ability to receive patent protection or protect our proprietary information may be impaired. In addition, under proposed or adopted policies in the EU, information related to clinical trials and clinical trial data that historically were considered confidential are now increasingly subject to public disclosure. The move toward public disclosure of this information could adversely affect our business in many ways, such as by requiring the disclosure of confidential methodologies for product development, preventing us from obtaining intellectual property right protection for innovations, requiring significant resources to prevent others from violating our intellectual property rights, adding complexity to compliance with applicable data privacy regulations, and enabling competitors to use our data to gain approvals for their own products.

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We may incur substantial costs and lose important rights or may not be able to continue to commercialize our products or to commercialize any of our product candidates that may be approved for commercial sale as a result of litigation or other proceedings relating to patent and other intellectual property rights, and we may be required to obtain patent and other intellectual property rights from others.

We may face potential lawsuits by companies, academic institutions or others alleging infringement of their intellectual property. Due to the amount of intellectual property in our field, we cannot be certain that we do not infringe intellectual property rights of competitors or that we will not infringe intellectual property rights of competitors granted or created in the future. In addition, we are monitoring the progress of multiple pending patent applications of other organizations that, if granted, may require us to license or challenge their enforceability in order to continue commercializing our products or to commercialize our product candidates that may be approved for commercial sale. Our challenges to patents of other organizations may not be successful, which may affect our ability to commercialize our products or product candidates. If it is ultimately determined that our products infringe a third-party’s intellectual property rights, we may be required to pay substantial damages, including lost profits, royalties, treble damages, attorneys’ fees and costs. Even if infringement claims against us are without merit, the results may be unpredictable. In addition, defending lawsuits takes significant time, may be expensive and may divert management’s attention from other business concerns. Further, we may be stopped from developing, manufacturing or selling our products unless and until we obtain a license from the owner of the relevant technology or other intellectual property rights, or we may be forced to undertake costly design-arounds, if feasible. If such a license is available at all, it may require us to pay substantial royalties or other fees.

We are or may be from time to time involved in the defense and enforcement of our patent or other intellectual property rights in a court of law, USPTO interference, inter partes review, or IPR, post-grant review or reexamination proceeding, foreign opposition proceeding or related legal and administrative proceeding in the U.S. and elsewhere. For example, we are involved in multiple disputes with Daiichi Sankyo Co. Ltd., or Daiichi Sankyo. In connection with one of these disputes, Daiichi Sankyo, Inc. and AstraZeneca Pharmaceuticals, LP, or AstraZeneca, filed two petitions for post-grant review with the USPTO, and on April 7, 2022, the Patent Trial and Appeal Board of the USPTO instituted two post-grant review proceedings. See the risk factor below titled, “We have been and may in the future be subject to litigation, which could result in substantial expenses and damages and may divert management’s time and attention from our business.” In addition, if we choose to go to court to stop a third party from infringing our patents, that third party has the right to ask the court to rule that these patents are invalid, not infringed and/or should not be enforced. Under the America Invents Act, a third party may also have the option to challenge the validity of certain patents at the Patent Trial and Appeal Board, or PTAB, of the USPTO whether they are accused of infringing our patents or not, and certain entities associated with hedge funds, pharmaceutical companies and other entities have challenged valuable pharmaceutical patents through the IPR process. These lawsuits and administrative proceedings are expensive and consume time and other resources, and we may not be successful in these proceedings or in stopping infringement. In addition, there is a risk that a court will decide that these patents are not valid or not infringed or otherwise not enforceable, or that the PTAB will decide that certain patents are not valid, and that we do not have the right to stop a third party from using the patented subject matter. Successful challenges to our patent or other intellectual property rights through these proceedings could result in a loss of rights in the relevant jurisdiction and may allow third parties to use our proprietary technologies without a license from us or our collaborators, which may also result in loss of future royalty payments. Furthermore, if such challenges to our rights are not resolved promptly in our favor, our existing business relationships may be jeopardized and we could be delayed or prevented from entering into new collaborations or from commercializing potential products, which could adversely affect our business, results of operations, financial condition and growth prospects. In addition, we may challenge the patent or other intellectual property rights of third parties and if we are unsuccessful in actions we bring against the rights of such parties, through litigation or otherwise, and it is determined that we infringe the intellectual property rights of such parties, we may be prevented from commercializing potential products in the relevant jurisdiction, or may be required to obtain licenses to those rights or develop or obtain alternative technologies, any of which could harm our business.

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We and our collaborators rely on license agreements for certain aspects of our products and product candidates and technologies such as our ADC technology. Failure to maintain these license agreements or to secure any required new licenses could prevent us from continuing to develop and commercialize our products and product candidates.

We have entered into agreements with third-party commercial and academic institutions to license technology for use in ADCETRIS, TUKYSA, our product candidates and technologies such as our ADC technology. Currently, we have license agreements with BMS, the University of Miami and Array BioPharma, Inc., among others. In addition to royalty provisions and other payment obligations, some of these license agreements contain diligence and milestone-based termination provisions, in which case our failure to meet any agreed upon royalty or diligence requirements or milestones may allow the licensor to terminate the agreement. Many of our license agreements grant us exclusive licenses to the underlying technologies. In addition, Astellas has agreements to license technology for use in PADCEV. We rely on Astellas to maintain these license agreements. If Astellas fails to maintain these license agreements, if our licensors terminate our license agreements or if we or our collaborators are unable to maintain the exclusivity of our exclusive license agreements, we may be unable to continue to develop and commercialize our products or product candidates. Further, we have had in the past, and we or our collaborators may in the future have, disputes with our licensors, which may impact our ability to develop and commercialize our products or product candidates or require us to enter into additional licenses. An adverse result in potential future disputes with our or our collaborators’ licensors may impact our ability to develop and commercialize our products and product candidates, or may require us to enter into additional licenses or to incur additional costs in litigation or settlement. In addition, continued development and commercialization of our products and product candidates will likely require us to secure licenses to additional technologies. We may not be able to secure these licenses on commercially reasonable terms, if at all.

We have been and may in the future be subject to litigation, which could result in substantial expenses and damages and may divert management’s time and attention from our business.

We are engaged in multiple legal disputes with Daiichi Sankyo. We are in a dispute with Daiichi Sankyo regarding the ownership of certain technology used by Daiichi Sankyo in its cancer drug ENHERTU and certain product candidates. A decision in the arbitration case is expected in mid-2022. In addition, we filed a complaint in the U.S. District Court for the Eastern District of Texas to commence an action for infringement of our U.S. Patent No. 10,808,039, or the ‘039 Patent, by Daiichi Sankyo’s importation into, offer for sale, sale, and use in the U.S. of ENHERTU. Daiichi Sankyo (as well as Daiichi Sankyo, Inc. and AstraZeneca) subsequently filed an action in the U.S. District Court for the District of Delaware seeking a declaratory judgment that ENHERTU does not infringe the ‘039 Patent. The Delaware action has been stayed by court order. Daiichi Sankyo, Inc. and AstraZeneca also filed two petitions for post-grant review with the USPTO seeking to have claims of the ‘039 Patent cancelled as unpatentable. On June 24, 2021, the USPTO issued a decision denying both petitions for post-grant review. On April 7, 2022, the Patent Trial and Appeal Board of the USPTO granted a request on rehearing and instituted two post-grant review proceedings. On April 8, 2022, a jury in the United States District Court for the Eastern District of Texas found that Daiichi Sankyo willfully infringed the asserted claims of the '039 Patent with its ENHERTU product, and also found that the asserted claims were not invalid. As a result of these disputes, we have incurred and will continue to incur litigation expenses. In addition, from time to time, we may become involved in other lawsuits, claims and proceedings relating to the conduct of our business, including those pertaining to the defense and enforcement of our patent or other intellectual property rights and our contractual rights.

These and other potential future litigations are subject to inherent uncertainties, and the actual costs to be incurred relating to litigations may be impacted by unknown factors. The outcome of litigation is necessarily uncertain, and we could be forced to expend significant resources in the course of these and potential future litigations, we may be subject to additional claims and counterclaims that may result in liabilities or require us to take or refrain from certain actions, and we may not prevail. Monitoring, defending against and pursuing legal actions can be time-consuming for our management and detract from our ability to fully focus our internal resources on our business activities, which could result in delays of our clinical trials or our development and commercialization efforts. In addition, we may incur substantial legal fees and costs in connection with these and potential future litigations. Decisions adverse to our interests in these and potential future litigations could result in the payment of substantial damages, or possibly fines, or affect our intellectual property rights and could have a material adverse effect on our business, results of operations, financial condition and growth prospects. Successful challenges to our patent or other intellectual property rights could result in a loss of rights in the relevant jurisdiction and may allow third parties to use our proprietary technologies without a license from us or our collaborators. In addition, the uncertainty associated with litigation could lead to increased volatility in our stock price.

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Risks Related to Our Operations, Managing Our Growth and Other Risks

The evolving effects of the COVID-19 pandemic and associated global economic instability could have further adverse effects on our business, including our commercialization efforts, supply chain, regulatory activities, clinical development activities and other business operations.

Our business is currently being adversely affected and could be materially and adversely affected in the future by the evolving effects of the COVID-19 pandemic. Our ongoing increased reliance on personnel working from home may present operational and workplace culture challenges, negatively impact productivity or disrupt, delay or otherwise adversely impact our business. This could also increase our cybersecurity risk, create data accessibility concerns and make us more susceptible to communication disruptions, any of which could adversely impact our business operations. Our field-based personnel are using a mix of in-person interactions and electronic communications, such as emails, phone calls and video conferences, to support healthcare providers and patients. Many healthcare professionals are facing additional demands on their time during the ongoing COVID-19 pandemic. We expect the different quality of electronic interactions as compared with in-person interactions, as well as the reduced quantity of interactions during the COVID-19 pandemic, to reduce the effectiveness of our sales personnel, as well as those of our collaborators, which could negatively affect our product sales and those of our collaborators, as well as physician awareness of our products. In this regard, we believe that the need to conduct some of our activities virtually is negatively impacting our ability to connect with key customers, including those familiar with competitive products, and our ability to conduct payor engagements.

We face a number of challenges that will limit our ability to fully resume in-person interactions, including increasing COVID-19 infection rates due to coronavirus mutations and/or low vaccination rates in different areas or otherwise, the need to navigate varying restrictions for entering healthcare facilities and the pandemic's impacts on employee childcare arrangements. In addition, we may subsequently decide or be forced to resume a more restrictive remote work model, whether as a result of further spikes or surges in COVID-19 infection or hospitalization rates or otherwise. Moreover, the long-term effects of the COVID-19 pandemic are also unknown and it is possible that following the pandemic, healthcare institutions could alter their policies with respect to in person visits by pharmaceutical company representatives. Future COVID-19 related restrictions could also present product distribution challenges.

The evolving effects of the COVID-19 pandemic appear to have negatively affected and may continue to negatively affect our product sales due to challenges in patient access to healthcare settings, loss of individual health insurance coverage, and inability to access government healthcare programs due to backlogs, some or all of which appear to have negatively affected diagnosis rates, may affect side effect management and course of treatment and may increase enrollment in our patient support programs. In this regard, impacts associated with the COVID-19 pandemic appear to have led to a reduction in the rate of Hodgkin lymphoma diagnoses, may have adversely affected diagnosis rates of other cancers, and may further adversely affect rates of cancer diagnoses in the future. We also expect that the conversion of medical conferences to a virtual format may reduce our ability to effectively disseminate scientific information about our products, which may result in decreased physician awareness of our products, their approved indications and their efficacy and safety.

Some of the sites participating in our clinical trials are affected by site closings, reduced capacity, staffing shortages or other effects of the COVID-19 pandemic. At some sites, we are experiencing impacts to our ability to monitor patients, activate sites, screen and enroll patients, complete site monitoring and manage samples. The extent of the impact on a particular clinical trial depends on the current stage of activities at a given site, for example study start up versus post-enrollment, and the number of impacted sites participating in that trial. Impacts on diagnosis rates associated with the COVID-19 pandemic may also negatively impact enrollment. While we do not at this time anticipate the need to revise our publicly reported projected clinical milestone dates as a result of the effects of the COVID-19 pandemic, there may continue to be adverse impacts to our clinical study timelines, which, depending upon the duration and severity of the evolving effects of the COVID-19 pandemic, could ultimately delay data availability. Due to the suspension of data monitoring activities at sites that do not currently allow remote monitoring, as well as impacts on the ability to monitor patients, maintain patient treatment according to the trial protocols and manage samples, there is also the potential for negative impacts on data quality. While we are actively utilizing digital monitoring measures and other mitigations designed to prevent negative data quality impacts, if there were in fact a negative impact on data quality, we or our collaborators could be required to repeat, extend the duration of, or increase the size of clinical trials, which could significantly delay potential commercialization and require greater expenditures. We expect that similar factors will impact clinical studies operationalized by our collaborators. In addition, many of our non-essential on-site research activities are currently significantly reduced as a result of the COVID-19 pandemic, which may negatively impact the number of investigational new drug application, or IND, candidates entering our clinical pipeline in future years.

The effects of the COVID-19 pandemic continue to rapidly evolve. These effects have increased market volatility and could result in a significant long-term disruption of global financial markets, reducing our ability to access capital, which could in the future negatively affect our liquidity. In addition, economic instability resulting from the effects of the COVID-19 pandemic could materially affect our business and the value of our common stock.

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The extent to which the evolving effects of the COVID-19 pandemic impact our business will depend on future developments that are highly uncertain, such as coronavirus variants that may prove to be especially contagious or virulent, the ultimate duration and severity of the pandemic, government actions, such as travel restrictions, quarantines and social distancing requirements in the U.S. and in other countries, business closures or business disruptions and the effectiveness of vaccine programs and other actions taken to contain and treat the disease. Accordingly, we do not yet know the full extent of potential effects from the pandemic. However, these effects could materially and adversely affect our business, results of operations, financial condition and growth prospects. In addition, the evolving effects of the COVID-19 pandemic may also heighten many of the other risks described elsewhere in this “Risk Factors” section. It is also possible that future global pandemics could occur and materially and adversely affect our business, results of operations, financial condition and growth prospects.

If we are unable to manage our growth, our business, results of operations, financial condition and growth prospects may be adversely affected.

We have experienced and expect to continue to experience significant growth in the number of our employees and in the scope and complexity of our operations. This rapid growth and additional complexity places significant demands on our management and other personnel, our operational and financial resources and our third party suppliers. Our current and planned personnel, operational and financial systems, procedures, controls and suppliers may not be adequate to support our growth, and we may experience operating inefficiencies, delays, control deficiencies, compliance issues or other problems. In addition, we may not be able to achieve any necessary growth objectives in a timely or cost-effective manner, or at all, and may not realize a positive return on our investment. If we are unable to manage our growth effectively, our business, results of operations, financial condition and growth prospects may be adversely affected.

Risks associated with our expanding operations in countries outside the U.S. could materially adversely affect our business.

We have operations outside the U.S., and we plan to continue expanding our operations internationally. For example, we are continuing to expand our commercial infrastructure in Europe and Canada. Consequently, we are, and will increasingly be, subject to risks and complexities related to operating internationally, including:

•the increased complexity and costs inherent in managing international operations, including in geographically disparate locations;

•diverse clinical, drug safety, drug quality, drug supply, healthcare compliance and other pharmaceutical regulatory regimes, and any future changes to such requirements, in the countries and regions where we are located or do business;

•multiple, differing and changing laws and regulations such as tax laws, privacy regulations, tariffs, trade restrictions, export and import restrictions, employment, immigration and labor laws, corporate laws, and other governmental approvals, permits and licenses;

•differing payor reimbursement regimes, governmental payors or patient self-pay systems and price controls;

•adverse tax consequences, including changes in applicable tax laws and regulations;

•political tensions, economic weakness, including inflation, or political or economic instability in particular economies and markets;

•currency fluctuations, which could result in increased operating expenses or reduced revenues;

•challenges inherent in efficiently managing employees in diverse geographies and different languages;

•challenges in adapting systems, policies, benefits and compliance programs for different countries;

•reliance on vendors who are located far from our headquarters and with whom we have not worked previously; and

•workforce uncertainty in countries where labor unrest is more common.

For example, the U.S. government and other nations have imposed significant restrictions on most companies’ ability to do business in Russia as a result of the ongoing military conflict between Russia and Ukraine. It is not possible to predict the broader or longer-term consequences of this conflict, which could include further sanctions, embargoes, regional instability, geopolitical shifts and adverse effects on macroeconomic conditions, security conditions, currency exchange rates and financial markets. Such geopolitical instability and uncertainty could have a negative impact on our ability to continue expanding our operations internationally and to otherwise generate revenues and develop our product candidates internationally. In addition, a significant escalation or expansion of economic disruption or the conflict's current scope could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

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Additionally, the U.S. Foreign Corrupt Practices Act, or FCPA, and the anti-bribery laws and regulations of other countries are extensive and far-reaching. We must ensure that accurate records and controls required by the FCPA are maintained with respect to the activities of our employees, distributors and service providers in all of the countries where we operate. In the course of conducting operations internationally, we interact with regulatory authorities, as well as with healthcare professionals who are often employed by governments and may be deemed to be foreign officials under the FCPA. Any interactions with any such third parties that are found to be in violation of relevant laws could result in substantial fines and penalties and could materially harm our business. Emerging-market countries may be especially vulnerable to periods of political, legal, and financial instability and may have a higher risk of corrupt business practices. As we expand our international operations, we continue to supplement and expand our global compliance program, controls, policies and procedures. However, there can be no assurance that such measures will work effectively at all times or protect us against liability. There is a risk that acts committed by our employees, agents, distributors, collaborators or third-party providers might violate the FCPA and other anti-corruption laws and that we might be held responsible. Furthermore, any finding of a violation under one country’s laws may increase the likelihood that we will be prosecuted and be found to have violated another country’s laws. Our failure, or the failure of others who we engage to act on our behalf, to comply with the laws and regulations of the countries in which we operate, or will operate in the future, could result in criminal and civil penalties, other remedial measures and reputational damage, all of which could materially harm our business, financial condition, results of operations, and prospects. As we continue to expand our footprint and activities internationally, our exposure to compliance risks under the FCPA and other similar laws will likewise increase.

As a business, we do not have significant experience conducting operations outside of the U.S. and Canada. We might not be successful in establishing and conducting commercial and other operations in these regions and may not realize a positive return on our investment. Our failure to successfully do so could have a material adverse effect on our business, results of operations, financial condition and growth prospects. These and other risks associated with expanding our international operations, as described elsewhere in these risk factors, could have a material adverse effect on our business, results of operations, financial condition and growth prospects.

We have engaged in, and may in the future engage in, strategic transactions that increase our capital requirements, dilute our stockholders, cause us to incur debt or assume contingent liabilities and subject us to other risks.

We actively evaluate various strategic transactions on an ongoing basis, including licensing or otherwise acquiring complementary products, product candidates, technologies or businesses. We may spend significant amounts, issue dilutive securities and/or assume or incur significant debt obligations in connection with these transactions. In addition, these transactions, including our recent in-license of development and commercialization rights to disitamab vedotin and any potential future acquisitions or licensing transactions, entail numerous risks, including:

•risks associated with satisfying the closing conditions relating to such transactions and realizing their anticipated benefits;

•increased operating expenses and cash requirements;

•difficulty integrating acquired technologies, products, operations, compliance programs and personnel with our existing business;

•acquired or licensed products, product candidates or technologies, such as disitamab vedotin, may not perform as expected and may not result in regulatory approvals;

•failure to successfully develop and commercialize acquired or licensed products, product candidates or technologies or to achieve other strategic objectives;

•the potential disruption of our historical core business;

•diversion of management’s attention in connection with both negotiating the acquisition or license and integrating the business, technology or product;

•retention of key employees;

•uncertainties in our ability to maintain key business relationships of any acquired companies;

•difficulty implementing and maintaining effective internal control over financial reporting of businesses that we acquire;

•exposure to unanticipated liabilities of acquired companies or companies in which we invest;

•the potential need to write down assets or recognize impairment charges or significant amortization expenses; and

•potential costly and time-consuming litigation, including stockholder lawsuits.

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As a result of these or other problems and risks, businesses, technologies or products we acquire or invest in or obtain licenses to may not produce the revenues, earnings, business synergies or other benefits that we anticipated, within the expected timeframe or at all. As a result, we may incur higher costs and realize lower revenues than we had anticipated. We cannot assure you that any acquisitions or investments we have made or may make in the future will be completed or that, if completed, the acquired business, licenses, investments, products, or technologies will generate sufficient revenue to offset the costs or other negative effects on our business. Further, while we seek to mitigate risks and liabilities of potential acquisitions and in-licensing transactions through, among other things, due diligence, there may be risks and liabilities that we fail to discover, that are not disclosed to us, or that we inadequately assess. Any failure in identifying and managing these risks, liabilities and uncertainties effectively, including in connection with our recent in-license of development and commercialization rights to disitamab vedotin, could have a material adverse effect on our business, results of operations, financial condition and growth prospects. Moreover, we may not be able to identify, negotiate and close strategic acquisition or in-licensing opportunities in the future, and this inability could impair our ability to grow or obtain access to technology or products that may be important to the development of our business. Other pharmaceutical companies, many of which may have substantially greater resources, compete with us for these opportunities. Failure to effectively advance our business strategy and manage our operations through acquisitions or in-licensing transactions could have a material adverse effect on our business, results of operations, financial condition, and growth prospects.

If we lose our key personnel or are unable to attract and retain additional qualified personnel, our future growth and ability to compete would suffer.

We are highly dependent on the efforts and abilities of the principal members of our senior management and other key personnel. For example, we have scientific personnel with significant and unique expertise in monoclonal antibodies, ADCs and related technologies, and our products and product candidates. The loss of the services of any one of the principal members of our managerial, scientific or other key staff may prevent us from achieving our business objectives.

In addition, the competition for qualified personnel in the biotechnology field is intense, and our future success depends upon our ability to attract, retain and motivate highly skilled biotechnology employees. In order to continue to commercialize our products, and advance the development and commercialization of our product candidates, we will be required to expand our workforce and management team, particularly in the areas of manufacturing, clinical trials, regulatory affairs, business development, sales and marketing, both in the U.S. and in Europe. We continue to face intense competition for qualified individuals from numerous pharmaceutical and biotechnology companies, as well as academic and other research institutions, and with increasing reliance on remote work arrangements, the geographic market in which we compete for talent is expanding. Our ability to attract and retain talent in this competitive environment may be further complicated by evolving employment trends arising from the COVID-19 pandemic, including an increased preference for remote, alternative or flexible work arrangements. Our failure to effectively compete for and retain talent could negatively affect our ability to achieve our business objectives and have a material adverse effect on our business, results of operations, financial condition and growth prospects.

If our information technology systems or data are or were compromised, we could experience interruptions to our operations, legal claims, liability, harm to our reputation, a loss of sales and other adverse impacts.

We and our collaborators, suppliers and service providers rely on information technology systems to keep financial and other records, capture laboratory and clinical trial data, support internal and external communications and operate other critical functions. Despite our security measures, these systems are potentially vulnerable to malware, cyber-attacks, security breaches, natural disasters, terrorism, software and hardware failures, telecommunication and electrical failures, and similar issues. If such an event were to occur, it could result in material interruptions to our operations, loss of data or applications, loss of sales, significant extra expenses to restore data or systems, reputational harm and diversion of funds. For example, the loss of preclinical study or clinical trial data could result in delays in our product development or regulatory approval efforts and significantly increase our costs in order to recover or reproduce the data. The effects of the COVID-19 pandemic have intensified our dependence on information technology systems as many of our critical business activities are currently being conducted remotely and our increased reliance on personnel working from home could increase our cybersecurity risk. In addition, our cybersecurity risk could be increased as a result of the ongoing military conflict between Russia and Ukraine and the related sanctions imposed against Russia.

In addition to traditional computer “hackers” and threat actors, sophisticated nation-state and nation-state supported actors now engage in attacks (including advanced persistent threat intrusions). Ransomware attacks, including those from organized criminal threat actors, nation-states and nation-state supported actors, are becoming increasingly prevalent and severe. To alleviate the financial, operational and reputational impact of a ransomware attack, it may be preferable to make extortion payments, but we may be unwilling or unable to do so (including, for example, if applicable laws or regulations prohibit such payments). Similarly, supply chain attacks have increased in frequency and severity. We cannot guarantee that third parties and infrastructure in our supply chain have not been compromised or that they do not contain exploitable defects or bugs that could result in a breach of or disruption to our systems and networks or the systems and networks of third parties that support us.

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Furthermore, because the techniques used to obtain unauthorized access to, or to sabotage, systems change frequently and often are not recognized until launched against a target, we may be unable to anticipate these techniques or implement adequate preventative measures. We may also experience security breaches that may remain undetected for an extended period. Although, to our knowledge, we have not experienced any material security breach to date, any such breach could compromise our networks and the information stored there could be accessed, publicly disclosed, lost or stolen. While we have taken steps to protect the security of the personal data and other sensitive information that we handle, there can be no assurance that any security measures will be effective against current or future security threats. Any unauthorized or accidental access to, or disclosure, modification, misuse, or loss of, personal or other data could result in legal claims or proceedings, liability, significant regulatory penalties, and loss of trade secrets or other intellectual property. In addition, such an event could disrupt our operations, damage our reputation and delay development of our product candidates.

Risks Related to Our Operating Results, Financial Condition and Capital Requirements

Our operating results are difficult to predict and may fluctuate. If our operating results are below the expectations of securities analysts or investors, the trading price of our stock could decline.

Our operating results are difficult to predict and may fluctuate significantly from quarter to quarter and year to year. We believe that our quarterly and annual results of operations may be affected by a variety of factors, including:

•customer ordering patterns for our products, which may vary significantly from period to period;

•the overall level of demand for our products, including the impact of any competitive or biosimilar products;

•the extent to which coverage and adequate reimbursement for our products is available from government and other third-party payors;

•changes in the amount of deductions from gross sales, including government-mandated rebates, chargebacks and discounts that can vary because of changes to the government discount percentage, including increases in the discount percentage resulting from price increases, or due to different levels of utilization by entities entitled to government rebates and discounts and changes in patient demographics;

•increases in the scope of eligibility for customers to purchase our products at the discounted government price or to obtain government-mandated rebates on purchases of our products;

•the timing, receipt and amount of development funding and milestone, royalty and other payments under collaboration and license arrangements, which may vary significantly from quarter to quarter;

•entry into new strategic transactions, such as collaborations, license agreements or acquisitions of products, technologies or businesses;

•changes in our cost of sales due to potential new product launches, royalties owed under technology license agreements or write-offs of inventory;

•the incidence rate of new patients in the approved indications for our products;

•the evolving effects of the COVID-19 pandemic, including those leading to past and potential future reductions in rates of cancer diagnoses;

•the timing, cost and level of investment in our sales and marketing efforts to support our products sales;

•the timing, cost and level of investment in clinical trials, research and development, pre-commercialization, manufacturing and other activities by us or our collaborators; and

•expenditures to develop and/or commercialize any additional products, product candidates, or technologies that we may develop, in-license, or acquire.

Sales of a newly-approved product, or sales an existing product in a newly-approved indication or territory, are particularly difficult to predict. Sales results or trends for such products, indications or territories in any period may not necessarily be indicative of future performance. Changes in our operations, such as new or expanding pipeline programs, the continued expansion or our international operations, additional business activities, or entry into strategic transactions, including potential future acquisitions of products, technologies or businesses, may cause significant fluctuations in our expenses. In addition, stock-based compensation expense may vary significantly from period to period. The variables we use for valuing these awards, including our underlying stock price, change over time. Additionally, from time to time, we have implemented long-term incentive plans for eligible employees, and the incentives provided under these plans are contingent upon the achievement of certain regulatory milestones. Costs of performance-based compensation under these plans are not recorded as an expense until the achievement of the applicable milestones is deemed probable, which may result in large fluctuations to the expense we must recognize in any particular period.

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For these and other reasons, it is difficult for us to accurately forecast future sales of our current or any future approved products, collaboration and license agreement revenues, royalty revenues, operating expenses or future profits or losses. In addition, although we provide financial guidance from time to time, such guidance is based on assumptions that may be incorrect or that may change from quarter to quarter. You also should not rely on operating results in any period as being indicative of future performance. Our operating results have on occasion been, and in in future periods may also be, below prior period results, our own guidance and/or the expectations of securities analysts or investors. Such results could cause the trading price of our common stock to decline, perhaps substantially.

We have a history of net losses. We expect to continue to incur net losses and may not achieve future sustained profitability for some time, if at all.

We have incurred substantial net losses in each of our years of operation, other than the year ended December 31, 2020. We have incurred these losses principally from costs incurred in our research and development programs and from our selling, general and administrative expenses. We expect to continue to spend substantial amounts on research and development, including amounts for conducting clinical trials of our products and product candidates. In addition, we expect to make substantial expenditures to commercialize our products and potentially commercialize our product candidates. For example, in connection with our in-license of development and commercialization rights to disitamab vedotin, we have incurred and expect to continue to incur substantial expenses, including to further develop and potentially commercialize disitamab vedotin. We may also pursue new operations or continue the expansion of our existing operations, including with respect to the continued development of our commercial infrastructure in Europe and our plans to otherwise continue to expand our operations internationally. Accordingly, we expect to continue to incur net losses in the future and may not achieve sustained profitability for some time, if at all. Although we recognize revenue from product sales and we continue to earn amounts under our collaboration agreements, our revenue and profit potential is unproven and our future operating results are difficult to predict. Even if we do achieve profitability in the future, we may not be able to sustain or increase profitability on a quarterly or annual basis. If we are unable to achieve and sustain profitability, the market value of our common stock will likely decline.

We may need to raise additional capital that may not be available to us.

We expect to make additional capital outlays and to increase operating expenditures over the next several years as we hire additional employees, support our development and commercialization activities, invest in our facilities, and expand globally, which may require us to raise additional capital. In addition, we may pursue new operations or continue the expansion of our existing operations, including with respect to the continued development of our commercial infrastructure in Europe and our plans to otherwise continue to expand our operations internationally. Our commitment of resources to the continuing development, regulatory and commercialization activities for our products, the continued research, development and manufacturing of our product candidates, our pursuit of regulatory approvals for and preparing to potentially launch and commercialize our product candidates, and the anticipated expansion of our pipeline and operations may require us to raise additional capital. Further, we actively evaluate various strategic transactions on an ongoing basis, including licensing or otherwise acquiring complementary products, technologies or businesses, and we may require significant additional capital in order to complete or otherwise provide funding for such transactions. We may seek additional capital through some or all of the following methods: corporate collaborations, licensing arrangements and public or private debt or equity financings. We do not know whether additional capital will be available when needed, or that, if available, we will obtain financing on terms favorable to us or our stockholders. If we are unable to raise additional funds when we need them, we may be required to scale back our operations, delay, reduce the scope of, or eliminate development programs enter into collaboration or license agreements on terms that are not favorable to us, sell or relinquish rights to certain assets, proprietary technologies or product candidates or forego strategic opportunities. Our future capital requirements will depend upon a number of factors, including:

•the level of sales of our products and any future approved products;

•the time and costs involved in pursuing regulatory approvals and the timing of any approvals;

•the costs, timing, progress and results of our research and development, including preclinical testing and clinical trials;

•the timing, receipt and amount of royalty revenue generated from commercial sales by our collaborators and licensees, as well as development funding, milestone payments and other payments under collaboration and license arrangements;

•the cost of establishing and maintaining clinical supplies of our products and product candidates and commercial supplies of our current and any future approved products;

•the extent of our investment in development, manufacturing and commercialization outside the U.S.;

•the costs associated with past and potential future strategic transactions, including acquisitions or licenses of additional technologies, products or businesses as well as licenses we may need to commercialize our current or any future approved products;

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•the terms and timing of any future collaboration, licensing and other arrangements;

•expenses associated with current or future litigation;

•the potential costs associated with international, state and federal taxes; and

•competing technological and market developments.

In addition, changes in our spending rate may occur that would consume available capital resources sooner, such as increased development, manufacturing and clinical trial expenses in connection with our expanding pipeline programs or our undertaking of additional programs, business activities or entry into additional strategic transactions, including potential future acquisitions of products, technologies or businesses. Moreover, we may choose to raise additional capital due to market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution. Debt financing arrangements may require us to pledge certain assets or enter into covenants that could restrict our operations or our ability to pay dividends or other distributions on our common stock or incur further indebtedness. To the extent that we raise additional funds through collaboration and licensing arrangements, we may be required to relinquish some rights to our technologies or product candidates, or grant licenses on terms that are not favorable to us.

During the past several years, domestic and international financial markets have experienced, and they may continue to experience, extreme disruption from time to time, including, among other things, high volatility, significant declines in stock prices and severely diminished liquidity and credit availability for both borrowers and investors. Such adverse capital and credit market conditions could make it more difficult to obtain additional capital on favorable terms, or at all, which could have a material adverse effect on our business and growth prospects. For example, our ability to raise additional capital may be adversely impacted by deteriorating global economic conditions and the disruptions to and volatility in the credit and financial markets in the U.S. and worldwide resulting from the evolving effects of the COVID-19 pandemic and the ongoing military conflict between Russian and Ukraine and related sanctions imposed against Russia.

The potential future impairment of intangible assets and goodwill may negatively affect our results of operations and financial position.

As of March 31, 2022, we carried $529.6 million of intangible assets, net and goodwill on our condensed consolidated balance sheet. Our intangible assets and goodwill are subject to an impairment analysis whenever events or changes in circumstances indicate the carrying amount of the asset may not be recoverable. Additionally, goodwill and indefinite-lived assets are subject to an impairment test at least annually. Events giving rise to impairment are an inherent risk in the pharmaceutical industry and cannot be predicted. Our results of operations and financial position in future periods could be negatively impacted should future impairments of intangible assets or goodwill occur.

Risks Related to Our Common Stock

Our stock price is volatile and our shares may suffer a decline in value.

The market price of our stock has been, and is likely to continue to be, volatile. As a result of fluctuations in the price of our common stock, you may be unable to sell your shares at or above the price you paid for them. The market price of our common stock may be subject to substantial volatility in response to many risk factors listed in this section, and others beyond our control, including:

•the levels of product sales;

•regulatory approval or non-approval of our products or product candidates, specific label indications for or restrictions, warnings or limitations in their use, or delays in the regulatory review process;

•clinical trial results;

•announcements regarding the results of discovery efforts, product development and commercial activities by us, our collaborators or our competitors;

•announcements regarding, or negative publicity concerning, adverse events or safety concerns associated with the use of our products or product candidates;

•issuance of new or changed analysts’ reports and recommendations regarding us or our competitors;

•termination of or changes in our existing collaborations or licensing arrangements, or establishment of new collaborations or licensing arrangements;

•our failure to achieve the perceived benefits of our strategic transactions, including our recent in-license of development and commercialization rights to disitamab vedotin, as rapidly or to the extent anticipated by financial analysts or investors;

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•our entry into additional material strategic transactions including licensing or acquisition of products, businesses or technologies;

•regulatory actions with respect to our products, product candidates, clinical trials or regulatory filings;

•our raising of additional capital and the terms upon which we may raise any additional capital;

•developments or disputes concerning our proprietary rights, including with respect to our disputes with Daiichi Sankyo;

•developments regarding any litigation or potential litigation;

•the evolving effects of the COVID-19 pandemic;

•share price and volume fluctuations attributable to inconsistent trading volume levels of our shares;

•changes in laws, regulations or government policies, including with respect to pricing and reimbursement;

•market conditions for equity investments in general, or the biotechnology or pharmaceutical industries in particular; and

•other economic, social or political conditions.

The stock markets in general, and the markets for biotechnology and pharmaceutical stocks in particular, have historically experienced significant volatility that has often been unrelated or disproportionate to the operating performance of particular companies. In the past, companies whose securities have experienced periods of volatility in market price have been subjected to securities class action or derivative litigation. In this regard, we have been, and may in the future again become, subject to claims and litigation alleging violations of the securities laws or other related claims. Lawsuits brought against us could result in substantial costs, which would hurt our financial condition and results of operations and divert management’s attention and resources.

Substantial future sales or issuances of shares of our common stock or equity-related securities could cause the market price of our common stock to decline.

Sales of a substantial number of shares of our common stock, and sales by members of our management or board of directors or entities affiliated with such members, could occur at any time. In addition, in December 2020, pursuant to a ten-year registration rights agreement we entered into with certain entities affiliated with Baker Bros. Advisors LP, or the Baker Entities, we registered up to 47,366,602 shares of our common stock for resale by the Baker Entities, and we may be required to register the resale of additional shares held by the Baker Entities from time to time in the future. Sales by our management, our directors, their affiliates, or significant shareholders like the Baker Entities, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce the market price of our common stock, perhaps substantially, and could impair our ability to raise capital through the sale of additional equity or equity-related securities. In addition, we may issue a substantial number of shares of our common stock or equity-related securities, including convertible debt, to meet our capital needs, including in connection with funding potential future acquisition or licensing opportunities, capital expenditures or product development costs. These issuances could be substantially dilutive and could adversely affect the market price of our common stock. Likewise, future issuances of our common stock upon the exercise, conversion or settlement of equity-based awards or other equity-related securities would dilute existing stockholders’ ownership interest in our company.

Our existing stockholders have significant control of our management and affairs.

Based on information available to us as of March 31, 2022, the Baker Entities collectively beneficially owned approximately 26% of our common stock. In addition, based solely on the most recent Schedules 13G and 13D filed with the SEC, reports filed with the SEC under Section 16 of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and our outstanding shares of common stock as of March 31, 2022, our executive officers and directors and holders of greater than five percent of our outstanding common stock beneficially owned approximately 54% of our voting power as of March 31, 2022. As a result, these stockholders are able to exert substantial influence over our management and affairs and matters requiring stockholder approval, including the election of directors and approval of significant corporate transactions, such as mergers, consolidations or the sale of substantially all of our assets. Consequently, this concentration of ownership may result in our taking corporate actions that other stockholders may not consider to be in their best interest. For example, it may have the effect of delaying, deferring or preventing a change in control, including a merger, consolidation, takeover or other business combination involving us or discourage a potential acquirer from making a tender offer or otherwise attempting to obtain control, which might affect the market price of our common stock.

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Anti-takeover provisions could make it more difficult for a third party to acquire us.

Our Board of Directors has the authority to issue up to 5,000,000 shares of preferred stock and to determine the terms of those shares, including voting rights, without any further action by the stockholders. The rights of the holders of common stock may be subject to, and may be adversely affected by, the rights of the holders of any preferred stock that may be issued in the future. The issuance of preferred stock may have the effect of delaying, deferring or preventing a change of control of Seagen. Further, certain provisions of our charter documents, including provisions eliminating the ability of stockholders to take action by written consent and limiting the ability of stockholders to raise matters at a meeting of stockholders without giving advance notice, may have the effect of delaying or preventing changes in control or management of Seagen, which could have an adverse effect on the market price of our stock. In addition, our charter documents provide for a classified board, which may make it more difficult for a third party to gain control of our Board of Directors. Similarly, state laws in Delaware and Washington related to corporate takeovers may prevent or delay a change of control of Seagen.

Our disclosures related to environmental, social and governance, or ESG, matters expose us to various risks, including risks to our reputation and stock price.

Investors are increasingly likely to factor ESG disclosures into their investment decisions. We have elevated the degree to which we manage, track and report on our ESG efforts and goals. Where provided, goal statements are aspirational, are subject to a number of risks, many of which are beyond our control, and are not guarantees. Our processes and operations may not always conform to various frameworks for identifying, measuring and reporting ESG metrics, and ESG reporting standards may change over time, either of which could result in significant revisions to reported metrics. In addition, our interpretation of reporting standards may differ from those of others. Any failure or perceived failure to pursue or fulfill our goals or to satisfy various reporting standards could have negative impacts on our reputation and stock price and expose us to litigation or government actions.

General Risk Factors

Changes in tax laws or regulations may have a material adverse effect on our business, results of operations, financial condition or growth prospects.

Due to economic and political conditions, new tax laws, statutes, rules, regulations or ordinances could be enacted at any time, which could adversely affect our business operations and financial performance. Further, existing tax laws, statutes, rules, regulations or ordinances could be interpreted, changed, modified or applied adversely to us. For example, the current U.S. presidential administration has proposed numerous corporate tax reform proposals including implementation of a minimum tax on book income and increasing taxation of international business operations. In addition, as we continue to expand our operations internationally, we may become increasingly subject to taxation in jurisdictions outside the U.S. Changes in corporate tax rates or in rules applicable to the realization of net deferred tax assets relating to our operations, the taxation of foreign earnings or the deductibility of expenses could have a material impact on the value of our deferred tax assets, result in significant one-time charges, increase our future tax expense or otherwise have a material adverse effect on our business, results of operations, financial condition or growth prospects.

If our facilities are damaged or our research and development, manufacturing or other business processes are interrupted, our business could be seriously harmed.

We conduct most of our business in a limited number of facilities. Damage or extended periods of interruption to these facilities due to fire, natural disaster, severe weather, power loss, communications failure, unauthorized entry or other events could cause significant disruption and/or delays in our research and development, manufacturing and commercial activities and could cause us to incur large expenses to repair or replace the facilities. Although we maintain property damage and business interruption insurance coverage on these facilities, our insurance might not cover all losses under such circumstances and our business may be seriously harmed by such disruption, delays and costs.

Legislative actions and new accounting pronouncements are likely to impact our future financial position or results of operations.

Future changes in financial accounting standards may cause adverse, unexpected revenue fluctuations and affect our financial position or results of operations. New pronouncements and varying interpretations of pronouncements have occurred with frequency in the past and are expected to occur again in the future. As a result we may be required to make changes in our accounting policies that could adversely affect our reported revenues and expenses, future profitability or financial position. The application of existing or future financial accounting standards, particularly those relating to the way we account for revenues and costs, could have a significant impact on our reported results.

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Item 6.    Exhibits

Exhibit		Incorporation By Reference
Number	Exhibit Description	Form	SEC File No.	Exhibit	Filing Date
2.1†	License Agreement dated as of August 8, 2021 between RemeGen Co. Ltd. and Seagen Inc.	8-K	000-32405	2.1	9/21/2021
3.1	Fourth Amended and Restated Certificate of Incorporation of Seagen Inc. (f/k/a Seattle Genetics, Inc.).	10-Q	000-32405	3.1	11/7/2008
3.2	Certificate of Amendment of Fourth Amended and Restated Certificate of Incorporation of Seagen Inc. (f/k/a Seattle Genetics, Inc.).	8-K	000-32405	3.3	5/26/2011
3.3	Certificate of Amendment of Fourth Amended and Restated Certificate of Incorporation of Seagen Inc. (f/k/a Seattle Genetics, Inc.).	8-K	000-32405	3.1	10/8/2020
3.4	Amended and Restated Bylaws of Seagen Inc.	8-K	000-32405	3.1	4/15/2022
4.1	Specimen Stock Certificate.	10-K	000-32405	4.2	2/12/2021
4.2	Investor Rights Agreement dated July 8, 2003 among Seagen Inc. (f/k/a Seattle Genetics, Inc.) and certain of its stockholders.	10-Q	000-32405	4.3	11/7/2008
4.3	Registration Rights Agreement dated September 10, 2015 between Seagen Inc. (f/k/a Seattle Genetics, Inc.) and the persons listed on Schedule A attached thereto.	8-K	000-32405	10.1	9/11/2015
10.1*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Clay Siegall.	10-K	000-32405	10.52	2/9/2022
10.2*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Roger Dansey.	10-K	000-32405	10.53	2/9/2022
10.3*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Vaughn Himes.	10-K	000-32405	10.54	2/9/2022
10.4*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Jean Liu.	10-K	000-32405	10.55	2/9/2022
10.5*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Charles Romp.	10-K	000-32405	10.56	2/9/2022
10.6*	Amended and Restated Employment Agreement dated February 9, 2022, between Seagen Inc. and Todd Simpson.	10-K	000-32405	10.57	2/9/2022
10.7*	Form of Performance-Based Stock Unit Grant Notice and Stock Unit Agreement under the Amended and Restated 2007 Equity Incentive Plan (Approved January 18, 2022)	10-K	000-32405	10.118	2/9/2022
10.8+*	Form of Stock Unit Grant Notice and Stock Unit Agreement for Non-employee Directors under the Amended and Restated 2007 Equity Incentive Plan (Approved February 10, 2022).	—	—	—	—
10.9+*	Form of Stock Option Agreement for Non-Employee Directors under the Amended and Restated 2007 Equity Incentive Plan (Approved February 10, 2022).	—	—	—	—
31.1+	Certification of Chief Executive Officer pursuant to Rule 13a-14(a).	—	—	—	—
31.2+	Certification of Chief Financial Officer pursuant to Rule 13a-14(a).	—	—	—	—
32.1+	Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350.	—	—	—	—
32.2+	Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350.	—	—	—	—
101	The following financial statements from the Company's Quarterly Report on Form 10-Q for the quarter ended March 31, 2022, formatted in Inline XBRL: (i) Condensed Consolidated Balance Sheets, (ii) Condensed Consolidated Statements of Comprehensive Loss, (iii) Condensed Consolidated Statements of Stockholders' Equity, (iv) Condensed Consolidated Statements of Cash Flows, and (v) Notes to Condensed Consolidated Financial Statements, tagged as blocks of text and including detailed tags.	—	—	—	—
104	Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101).	—	—	—	—

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+	Filed herewith.
†	Certain confidential information contained in this Exhibit, marked by brackets in the Exhibit, has been omitted, because it is both not material and is the type that the registrant treats as private or confidential.
*	Indicates a management contract or compensatory plan or arrangement.

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SIGNATURE

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

SEAGEN INC.
By:	/s/ Todd E. Simpson
	Todd E. Simpson
	Duly Authorized and Chief Financial Officer
	(Principal Financial and Accounting Officer)
Date:	April 28, 2022

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EX-10.8

Exhibit 10.8 2-10-2022 SEAGEN INC. STOCK UNIT GRANT NOTICE (AMENDED AND RESTATED 2007 EQUITY INCENTIVE PLAN) Seagen Inc. (the “Company”), pursuant to its Amended and Restated 2007 Equity Incentive Plan (the “Plan”), hereby awards to Participant a Stock Unit Award for the number of stock units set forth below (the “Award”). The Award is subject to all of the terms and conditions as set forth herein and in the Plan and the Stock Unit Agreement, both of which are incorporated herein in their entirety. Capitalized terms not otherwise defined herein shall have the meanings set forth in the Plan or the Stock Unit Agreement, as applicable. Except as otherwise explicitly provided herein, in the event of any conflict between the terms in the Award and the Plan, the terms of the Plan shall control. Participant: Date of Grant: Number of Stock Units Subject to Award: Consideration: Participant’s Services Vesting Schedule: Subject to Section 2 of the Stock Unit Agreement, [this Award shall vest in full on the first anniversary of the Date of Grant] [one-quarter of the shares subject to the Award will vest each year on the anniversary of the Date of Grant until the Award is fully vested on the fourth anniversary of the Date of Grant]. Notwithstanding the foregoing, vesting shall terminate upon the Participant’s Termination of Employment. Issuance Schedule: The Shares to be issued in respect of the Award will be issued in accordance with the issuance schedule set forth in Section 6 of the Stock Unit Agreement.

Exhibit 10.8 2-10-2022 Additional Terms/Acknowledgements: Participant acknowledges receipt of, and understands and agrees to, this Stock Unit Grant Notice, the Stock Unit Agreement and the Plan. Participant also acknowledges receipt of the Prospectus for the Plan. Participant further acknowledges that as of the Date of Grant, this Stock Unit Grant Notice, the Stock Unit Agreement and the Plan set forth the entire understanding between Participant and the Company regarding the Award and supersede all prior oral and written agreements on that subject, with the exception of any arrangement that would provide for vesting acceleration of the Award upon the terms and conditions set forth therein. SEAGEN INC. PARTICIPANT: By: (Signature) Name: Clay B. Siegall, Ph.D. Title: President & CEO Date: Date:

1. 2-10-2022 SEAGEN INC. AMENDED AND RESTATED 2007 EQUITY INCENTIVE PLAN STOCK UNIT AGREEMENT Pursuant to the Stock Unit Grant Notice (“Grant Notice”) and this Stock Unit Agreement (this “Agreement”) and in consideration of your services, Seagen Inc. (the “Company”) has awarded you a Stock Unit Award (the “Award”) under its Amended and Restated 2007 Equity Incentive Plan (the “Plan”). Your Award is granted to you effective as of the Date of Grant set forth in the Grant Notice for this Award. This Agreement shall be deemed to be agreed to by the Company and you upon the signing by you of the Stock Unit Grant Notice to which it is attached. Capitalized terms not explicitly defined in this Agreement shall have the same meanings given to them in the Plan or the Grant Notice, as applicable. Except as otherwise explicitly provided herein, in the event of any conflict between the terms in this Agreement and the Plan, the terms of the Plan shall control. The details of your Award, in addition to those set forth in the Grant Notice and the Plan, are as follows. 1. GRANT OF THE AWARD. This Award represents the right to be issued on a future date the number of Shares that is equal to the number of stock units indicated in the Grant Notice (the “Stock Units”). As of the Date of Grant, the Company will credit to a bookkeeping account maintained by the Company for your benefit (the “Account”) the number of Stock Units subject to the Award. This Award is granted in consideration of your services to the Company. Except as otherwise provided herein, you will not be required to make any payment to the Company (other than past and future services to the Company) with respect to your receipt of the Award, the vesting of the Stock Units or the delivery of the Shares to be issued in respect of the Award. 2. VESTING. Subject to the limitations contained herein, your Award will vest, if at all, in accordance with the vesting schedule provided in the Grant Notice, provided that you have not incurred a Termination of Employment before the vesting date set forth in the Grant Notice. Upon your Termination of Employment, the Stock Units credited to the Account that are not vested on the date of such Termination of Employment will be forfeited at no cost to the Company and you will have no further right, title or interest in the Stock Units or the Shares to be issued in respect of the Award. Notwithstanding the foregoing or anything in this Agreement to the contrary, in the event of your Termination of Employment as a result of your death or Disability, the vesting of your Award shall accelerate such that your Award shall become vested as to an additional twelve (12) months, effective as of the date of such Termination of Employment, to the extent that your Award is outstanding on such date. In the event of a Change in Control (as defined in the Plan), the vesting of your Award (if your Award is outstanding at such time) shall be accelerated in full immediately prior to the effective time of the Change in Control.

2. 2-10-2022 3. NUMBER OF SHARES. (a) The number of Stock Units subject to your Award may be adjusted from time to time for changes in capitalization, as provided in Section 13 of the Plan. (b) Any additional Stock Units that become subject to the Award pursuant to this Section 3 shall be subject, in a manner determined by the Administrator, to the same forfeiture restrictions, restrictions on transferability, and time and manner of delivery as applicable to the other Stock Units covered by your Award. (c) Notwithstanding the provisions of this Section 3, no fractional Shares or rights for fractional Shares shall be created pursuant to this Section 3. The Administrator shall, in its discretion, determine an equivalent benefit for any fractional Shares or fractional Shares that might be created by the adjustments referred to in this Section 3. 4. SECURITIES LAW COMPLIANCE. You may not be issued any Shares in respect of your Award unless either (i) such Shares are registered under the Securities Act; or (ii) the Company has determined that such issuance would be exempt from the registration requirements of the Securities Act. Your Award also must comply with other applicable laws and regulations governing the Award, and you will not receive such Shares if the Company determines that such receipt would not be in material compliance with such laws and regulations. You represent and warrant that you (a) have been furnished with a copy of the prospectus for the Plan and all information deemed necessary to evaluate the merits and risks of receipt of the Award, (b) have had the opportunity to ask questions concerning the information received about the Award and the Company, and (c) have been given the opportunity to obtain any information you deem necessary to verify the accuracy of any information obtained concerning the Award and the Company. 5. TRANSFER RESTRICTIONS. Your Award is not transferable, except by will or by the laws of descent and distribution. In addition to any other limitation on transfer created by applicable securities laws, you agree not to assign, hypothecate, donate, encumber or otherwise dispose of any interest in any of the Shares subject to the Award until such Shares are issued to you in accordance with Section 6 of this Agreement. After such Shares have been issued to you, you are free to assign, hypothecate, donate, encumber or otherwise dispose of any interest in such Shares provided that any such actions are in compliance with the provisions herein and applicable securities laws. Notwithstanding the foregoing, by delivering written notice to the Company, in a form satisfactory to the Company, you may designate a third party who, in the event of your death, shall thereafter be entitled to receive any distribution of Shares to which you were entitled at the time of your death pursuant to this Agreement. 6. DATE OF ISSUANCE. (a) If the Award is exempt from application of Section 409A of the Code and any state law of similar effect (collectively “Section 409A”), the Company will deliver to you a number of Shares equal to the number of vested Stock Units subject to your Award, including any additional Stock Units received pursuant to Section 3 above that relate to those vested Stock Units

3. 2-10-2022 on the applicable vesting date (the “Original Issuance Date”). However, if the Original Issuance Date falls on a date that is not a business day, such delivery date shall instead fall on the next following business day. Notwithstanding the foregoing, if (i) the Original Issuance Date does not occur (1) during an “open window period” applicable to you, as determined by the Company in accordance with the Company’s then-effective policy or policies on trading in Company securities or (2) on a date when you are otherwise permitted to sell Shares on the open market; and (ii) the Company elects, prior to the Original Issuance Date, (x) not to satisfy the Withholding Obligation (as defined in Section 10(a) hereof), if any, by withholding Shares from the Shares otherwise due, on the Original Issuance Date, to you under this Award pursuant to Section 10 hereof, (y) not to permit you to sell Shares pursuant to a written plan that meets the requirements of Rule 10b5-1 under the Exchange Act, and (z) not to permit you to satisfy the Withholding Obligation in cash, then such Shares shall not be delivered on such Original Issuance Date and shall instead be delivered on the first business day of the next occurring open window period applicable to you or the next business day when you are not prohibited from selling Shares on the open market, as applicable (and regardless of whether there has been a Termination of Employment before such time), but in no event later than the 15th day of the third calendar month of the calendar year following the calendar year in which the Stock Units vest. Delivery of the Shares pursuant to the provisions of this Section 6(a) is intended to comply with the requirements for the short-term deferral exemption available under Treasury Regulations Section 1.409A-1(b)(4) and shall be construed and administered in such manner. The form of such delivery of the Shares (e.g., a stock certificate or electronic entry evidencing such Shares) shall be determined by the Company. (b) The provisions of this Section 6(b) are intended to apply if the Award is subject to Section 409A because of the terms of a severance arrangement or other agreement between you and the Company, if any, that provide for acceleration of vesting of the Award upon your separation from service (as such term is defined in Section 409A(a)(2)(A)(i) of the Code (“Separation from Service”) and such severance benefit does not satisfy the requirements for an exemption from application of Section 409A provided under Treasury Regulations Section 1.409A-1(b)(4) or 1.409A-1(b)(9) (“Non-Exempt Severance Arrangement”). If the Award is subject to and not exempt from application of Section 409A due to application of a Non-Exempt Severance Arrangement, the following provisions in this Section 6(b) shall supersede anything to the contrary in Section 6(a). (i) If the Award vests in the ordinary course before your Termination of Employment in accordance with the vesting schedule set forth in the Grant Notice, without accelerating vesting under the terms of a Non-Exempt Severance Arrangement, in no event will the Shares to be issued in respect of your Award be issued any later than December 31st of the calendar year that includes the applicable vesting date. (ii) If vesting of the Award accelerates under the terms of a Non-Exempt Severance Arrangement in connection with your Separation from Service, and such vesting acceleration provisions were in effect as of the date of grant of the Award and, therefore, are part of the terms of the Award as of the date of grant, then the Shares will be earlier issued in respect of your Award upon your Separation from Service in accordance with the terms of the Non-Exempt

4. 2-10-2022 Severance Arrangement, but in no event later than the 60th day that follows the date of your Separation from Service. However, if at the time the Shares would otherwise be issued you are subject to the distribution limitations contained in Section 409A applicable to “specified employees,” as defined in Section 409A(a)(2)(B)(i) of the Code, such Shares shall instead be issued on the date that is six months following the date of your Separation from Service, or, if earlier, the date of your death that occurs within such six-month period. (iii) If either (A) vesting of the Award accelerates under the terms of a Non-Exempt Severance Arrangement in connection with your Separation from Service, and such vesting acceleration provisions were not in effect as of the date of grant of the Award and, therefore, are not a part of the terms of the Award on the date of grant, or (B) vesting accelerates pursuant to Section 4(b) or Section 13 of the Plan, then such acceleration of vesting of the Award shall not accelerate the issuance date of the Shares (or any substitute property), but such Shares (or substitute property) shall instead be issued on the same schedule as set forth in the Grant Notice as if they had vested in the ordinary course before your Termination of Employment, notwithstanding the vesting acceleration of the Award. Such issuance schedule is intended to satisfy the requirements of payment on a specified date or pursuant to a fixed schedule, as provided under Treasury Regulations Section 1.409A-3(a)(4). (c) Notwithstanding anything to the contrary set forth herein, the Company explicitly reserves the right to earlier issue the Shares in respect of the Award to the extent permitted and in compliance with the requirements of Section 409A, including pursuant to any of the exemptions available in Treasury Regulations Section 1.409A-3(j)(4)(ix). (d) The provisions in this Agreement for delivery of the Shares in respect of the Award are intended either to comply with the requirements of Section 409A or to provide a basis for exemption from such requirements so that the vesting or delivery of such Shares will not trigger the additional tax imposed under Section 409A, and any ambiguities herein will be so interpreted. (e) The Administrator may modify the terms of this Agreement and/or the Plan without your consent, in the manner that the Administrator may determine to be necessary or advisable in order to comply with Code Section 409A or to mitigate any additional tax, interest and/or penalties or other adverse tax consequences that may apply under Code Section 409A if compliance is not practical. This Section 6(e) does not create an obligation on the part of the Company to modify the terms of this Agreement or the Plan and does not guarantee that this Award or the delivery of Shares upon settlement of the Award will not be subject to taxes, interest and penalties or any other adverse tax consequences under Code Section 409A. Nothing in this Agreement shall provide a basis for any person to take any action against the Company based on matters covered by Code Section 409A, including the tax treatment of any amounts paid under this Agreement, and the Company will not have any liability under any circumstances to the Participant or any other party if the Award, the delivery of Shares upon vesting/settlement of the Award or other payment or tax event hereunder that is intended to be exempt from, or compliant with, Code Section 409A, is not so exempt or compliant or for any action taken by the Administrator with respect thereto.

5. 2-10-2022 7. DIVIDENDS. You shall receive no benefit or adjustment to your Award with respect to any cash dividend, stock dividend or other distribution that does not result from a change in capitalization as provided in Section 13 of the Plan; provided, however, that this sentence shall not apply with respect to any Shares that are delivered to you in connection with your Award after such Shares have been delivered to you. 8. [RESERVED]. 9. AWARD NOT A SERVICE CONTRACT. (a) Your service with the Company or an Affiliate is not for any specified term and may be terminated by you or by the Company or an Affiliate at any time, for any reason, with or without cause and with or without notice. Nothing in this Agreement (including, but not limited to, the vesting of your Award pursuant to the schedule set forth in Section 2 herein or the issuance of the Shares in respect of your Award), the Plan or any covenant of good faith and fair dealing that may be found implicit in this Agreement or the Plan shall: (i) confer upon you any right to continue in the service of, or affiliation with, the Company or an Affiliate; (ii) constitute any promise or commitment by the Company or an Affiliate regarding the fact or nature of future positions, future work assignments, future compensation or any other term or condition of service or affiliation; (iii) confer any right or benefit under this Agreement or the Plan unless such right or benefit has specifically accrued under the terms of this Agreement or Plan; or (iv) deprive the Company or an Affiliate of the right to terminate you at will and without regard to any future vesting opportunity that you may have. (b) By accepting this Award, you acknowledge and agree that the right to continue vesting in the Award pursuant to the schedule set forth in Section 2 is earned only by continuing as an employee, director or consultant at the will of the Company (not through the act of being hired, being granted this Award or any other award or benefit) and that the Company has the right to reorganize, sell, spin-out or otherwise restructure one or more of its businesses or Affiliates at any time or from time to time, as it deems appropriate (a “reorganization”). You further acknowledge and agree that such a reorganization could result in your Termination of Employment, or the termination of Affiliate status with the Company and the loss of benefits available to you under this Agreement, including but not limited to, the termination of the right to continue vesting in the Award. You further acknowledge and agree that this Agreement, the Plan, the transactions contemplated hereunder and the vesting schedule set forth herein or any covenant of good faith and fair dealing that may be found implicit in any of them do not constitute an express or implied promise of continued engagement as an employee or consultant for the term of this Agreement, for any period, or at all, and shall not interfere in any way with your right or the Company’s right to terminate your service at any time, with or without cause and with or without notice.

6. 2-10-2022 10. WITHHOLDING OBLIGATIONS. (a) On or before the time you receive a distribution of Shares pursuant to your Award, or at any time thereafter as requested by the Company, you hereby authorize any required withholding from the Shares issuable to you and/or otherwise agree to make adequate provision in cash for any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Company or any Affiliate which arise in connection with your Award (the “Withholding Obligation”), if any. (b) Additionally, the Company may, at its discretion, satisfy the Withholding Obligation, if any, by the following means (or by a combination of the following means): (i) Requiring you to pay to the Company any portion of the Withholding Obligation in cash; (ii) Withholding from any compensation otherwise payable to you by the Company; (iii) Withholding Shares from the Shares issued or otherwise issuable to you in connection with the Award with a Fair Market Value (measured as of the date Shares are issued pursuant to Section 6) equal to the amount of the Withholding Obligation; provided, however, that the number of such Shares so withheld shall not exceed the amount necessary to satisfy the Company’s or Affiliate’s required tax withholding obligations using the minimum statutory withholding rates for federal, state, local and foreign tax purposes, including payroll taxes, that are applicable to supplemental taxable income (or such other amount as may be permitted while still avoiding classification of the Award as a liability for financial accounting purposes); and/or (iv) Permitting you to enter into a “same day sale” commitment with a broker-dealer that is a member of the Financial Industry Regulatory Authority (a “FINRA Dealer”) whereby you irrevocably elect to sell a portion of the Shares to be delivered in connection with your Award to satisfy the Withholding Obligation and whereby the FINRA Dealer irrevocably commits to forward the proceeds necessary to satisfy the Withholding Obligation directly to the Company and/or its Affiliates. (c) Unless the Withholding Obligation, if any, of the Company and/or any Affiliate are satisfied, the Company shall have no obligation to deliver to you any Shares. (d) In the event the Withholding Obligation, if any, of the Company arises prior to the delivery to you of Shares or it is determined after the delivery of Shares to you that the amount of the Withholding Obligation was greater than the amount withheld by the Company, you agree to indemnify and hold the Company harmless from any failure by the Company to withhold the proper amount.

7. 2-10-2022 11. UNSECURED OBLIGATION. Your Award is unfunded, and as a holder of a vested Award, you shall be considered an unsecured creditor of the Company with respect to the Company’s obligation, if any, to issue Shares pursuant to this Agreement. You shall not have voting or any other rights as a stockholder of the Company with respect to the Shares to be issued pursuant to this Agreement until such Shares are issued to you pursuant to Section 6 of this Agreement. Upon such issuance, you will obtain full voting and other rights as a stockholder of the Company. Nothing contained in this Agreement, and no action taken pursuant to its provisions, shall create or be construed to create a trust of any kind or a fiduciary relationship between you and the Company or any other person. 12. OTHER DOCUMENTS. You hereby acknowledge receipt or the right to receive a document providing the information required by Rule 428(b)(1) promulgated under the Securities Act, which includes the Plan prospectus. In addition, you acknowledge receipt of the Company’s policy on trading in Company securities permitting insiders to sell Shares only during certain “window” periods and the Company’s insider trading policy, in effect from time to time. 13. DATA TRANSFER. You hereby explicitly and unambiguously consent to the collection, use and transfer, in electronic or other form, of your personal data as described in this document by the Company for the purpose of implementing, administering and managing your participation in the Plan. You understand that the Company holds certain personal information about you, including, but not limited to, your name, home address and telephone number, date of birth, social security number (or other identification number), salary, nationality, job title, any shares of stock or directorships held in the Company, details of all options or any other entitlement to shares of stock awarded, canceled, purchased, exercised, vested, unvested or outstanding in your favor for the purpose of implementing, managing and administering the Plan (“Data”). You understand that the Data may be transferred to any third parties assisting in the implementation, administration and management of the Plan, including providing ancillary services related to stock plan administration. You authorize the recipients to receive, possess, use, retain and transfer the Data, in electronic or other form, for the purposes of implementing, administering and managing your participation in the Plan (including providing ancillary services related to stock plan administration), including any requisite transfer of such Data, as may be required to a broker or other third party with whom you may elect to deposit any shares issued in respect of your Award. 14. NOTICES; ELECTRONIC DELIVERY AND ACCEPTANCE. Any notices provided for in your Award or the Plan shall be given in writing and shall be deemed effectively given upon receipt or, in the case of notices delivered by the Company to you, five (5) days after deposit in the United States mail, postage prepaid, addressed to you at the last address you provided to the Company. Notwithstanding the foregoing, the Company may, in its sole discretion, decide to deliver any documents related to participation in the Plan and this Award by electronic means or to request your consent to participate in the Plan by electronic means. You hereby consent to receive such documents by electronic delivery and, if requested, to agree to participate in the Plan through an on-line or electronic system established and maintained by the Company, the Agent or another third party designated by the Company and agree notice shall be provided upon posting to your electronic account held by the Company, the Agent or another third party designated by the

8. 2-10-2022 Company. You hereby acknowledge that delivery, execution and acceptance of this or any other such documents by electronic means constitutes valid and effective delivery, execution and acceptance and shall be legally effective to create a valid and binding agreement. 15. MISCELLANEOUS. (a) The rights and obligations of the Company under your Award shall be transferable by the Company to any one or more persons or entities, and all covenants and agreements hereunder shall inure to the benefit of, and be enforceable by the Company’s successors and assigns. Your rights and obligations under your Award may only be assigned with the prior written consent of the Company. (b) You agree upon request to execute any further documents or instruments necessary or desirable in the sole determination of the Company to carry out the purposes or intent of your Award. (c) You acknowledge and agree that you have reviewed your Award in its entirety, have had an opportunity to obtain the advice of counsel prior to executing and accepting your Award, and fully understand all provisions of your Award. (d) This Agreement shall be subject to all applicable laws, rules, and regulations, and to such approvals by any governmental agencies or national securities exchanges as may be required. (e) All obligations of the Company under the Plan and this Agreement shall be binding on any successor to the Company, whether the existence of such successor is the result of a direct or indirect purchase, merger, consolidation, or otherwise, of all or substantially all of the business and/or assets of the Company. 16. GOVERNING PLAN DOCUMENT. Your Award is subject to all the provisions of the Plan, the provisions of which are hereby made a part of your Award, and is further subject to all interpretations, amendments, rules and regulations which may from time to time be promulgated and adopted pursuant to the Plan. Except as expressly provided herein, in the event of any conflict between the provisions of your Award and those of the Plan, the provisions of the Plan shall control. 17. ENTIRE AGREEMENT. The Plan, this Agreement and the Grant Notice constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and you with respect to the subject matter hereof, with the exception of any arrangement that would provide for vesting acceleration of this Award upon the terms and conditions set forth therein. This Agreement is governed by the laws of the state of Delaware. 18. SEVERABILITY. If all or any part of this Agreement or the Plan is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity shall

9. 2-10-2022 not invalidate any portion of this Agreement or the Plan not declared to be unlawful or invalid. Any Section of this Agreement (or part of such a Section) so declared to be unlawful or invalid shall, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid. 19. EFFECT ON OTHER EMPLOYEE BENEFIT PLANS. In the event that you become an Employee, the value of the Award subject to this Agreement shall not be included as compensation, earnings, salaries, or other similar terms used when calculating your benefits under any employee benefit plan sponsored by the Company or any Affiliate, except as such plan otherwise expressly provides. The Company expressly reserves its rights to amend, modify, or terminate any of the Company’s or any Affiliate’s employee benefit plans. 20. AMENDMENT. This Agreement may not be modified, amended or terminated except by an instrument in writing, signed by you and by a duly authorized representative of the Company. Notwithstanding the foregoing, this Agreement may be amended solely by the Administrator by a writing which specifically states that it is amending this Agreement, so long as a copy of such amendment is delivered to you, and provided that no such amendment materially adversely affecting your rights hereunder may be made without your written consent, except as otherwise provided in the Plan. Without limiting the foregoing, the Administrator reserves the right to change, by written notice to you and without your prior written consent, the provisions of this Agreement in any way it may deem necessary or advisable to carry out the purpose of the grant to facilitate compliance with applicable laws or regulations or any future law, regulation, ruling, or judicial decision.

EX-10.9

Exhibit 10.9 1 2-10-2022 SEAGEN INC. AMENDED AND RESTATED 2007 EQUITY INCENTIVE PLAN NOTICE OF STOCK OPTION GRANT «Name» «Title» «CompanyInstitute» «Address» «Address2» «City_State_Zip» Dear «Salutation»: You have been granted an option to purchase Common Stock of Seagen Inc. as follows: Date of Grant [_______] Exercise Price per Share [$______] Total Number of Shares Granted [_______] Type of Option Nonstatutory Stock Option Expiration Date [________] Vesting Schedule: Subject to Section 3 of the Stock Option Agreement, this Option may be exercised, in whole or in part, in accordance with the following schedule, provided that Optionee does not experience a Termination of Employment before the applicable vesting date: [One hundred percent (100%) of the total number of Shares subject to the Option shall vest on the first anniversary of the Grant Date] [One-fourth (1/4th) of the total number of Shares subject to the Option shall vest on the first anniversary of the Grant Date, and one thirty-sixth (1/36th) of the remaining Shares subject to the Option shall vest each month thereafter until all Shares are fully vested]. Termination Period: This Option may be exercised for three months after Optionee’s Termination of

Exhibit 10.9 2 2-10-2022 Employment, or such longer period as may be applicable upon the death or Disability of Optionee as provided in the Stock Option Agreement, but in no event later than the Expiration Date as provided above.

Exhibit 10.9 3 2-10-2022 By your signature and the signature of the Company’s representative below, you and Seagen Inc. agree that this Option is granted under and governed by the terms and conditions of the Seagen Inc. Amended and Restated 2007 Equity Incentive Plan and the Stock Option Agreement, all of which are attached and made a part of this document. OPTIONEE SEAGEN INC. By: «Name» Clay B. Siegall, Ph.D. President & CEO Social Security Number

Exhibit 10.9 4 2-10-2022 SEAGEN INC. AMENDED AND RESTATED 2007 EQUITY INCENTIVE PLAN STOCK OPTION AGREEMENT THIS STOCK OPTION AGREEMENT (the “Agreement”) dated [________] (“Grant Date”) between Seagen Inc., a Delaware corporation (the “Company”), and «Name» (“Optionee”), is entered into as follows: WITNESSETH: WHEREAS, the Company has established the Amended and Restated 2007 Equity Incentive Plan (the “Plan”); and WHEREAS, the Board of Directors of the Company (the “Board”) has determined that Optionee shall be granted an option under the Plan as hereinafter set forth; The parties hereby agree that the Company grants, effective as of the Grant Date, Optionee a Nonstatutory Stock Option (this “Option”) to purchase [________] shares of its $0.001 par value Common Stock (the “Shares”) upon the terms and conditions set forth in this Agreement. 1. Plan Award. This Option is granted under and pursuant to the Plan and is subject to each and all of the provisions thereof. 2. Exercise Price. The exercise price applicable to this Option (meaning, the price Optionee must pay in order to purchase any Shares hereunder) shall be [$_______] per Share. 3. Vesting and Exercise of Option. Subject to Optionee’s not experiencing a Termination of Employment during the following vesting period, Optionee shall vest in and earn the right to exercise this Option as follows: [One hundred percent (100%) of the total number of Shares subject to the Option shall vest on the first anniversary of the Grant Date] [One-fourth (1/4th) of the total number of Shares subject to the Option shall vest on the first anniversary of the Grant Date, and one thirty-sixth (1/36th) of the remaining Shares subject to the Option shall vest each month thereafter until all Shares are fully vested]. This Option may be exercised in whole or in part. Notwithstanding the foregoing or anything in this Agreement to the contrary, in the event of Optionee's Termination of Employment as a result of Optionee's death or Disability, the vesting and exercisability of this Option shall accelerate such that this Option shall become vested and exercisable as to an additional twelve (12) months, effective as of the date of such Termination of Employment, to the extent that this Option is outstanding on such date. In the event of a Change in Control (as defined in the Plan), the vesting of this Option (if this Option is outstanding at such time) shall be accelerated in full such that Optionee shall have the right to exercise this Option for all of the Shares subject to this Option immediately prior to the effective time of the Change in Control.

Exhibit 10.9 5 2-10-2022 4. Expiration. This Option will expire ten (10) years from the Grant Date, unless sooner terminated or canceled in accordance with the provisions of the Plan. This means that (subject to the continuing service requirement set forth in Section 3 above and subject to earlier termination upon certain other events as set forth in the Plan) this Option must be exercised, if at all, on or before [________] (the “Expiration Date”). If this Option expires on a stock exchange holiday or weekend day, this Option will expire on the last trading day prior to the holiday or weekend. Optionee shall be solely responsible for exercising this Option, if at all, prior to its Expiration Date. The Company shall have no obligation to notify Optionee of this Option's expiration. 5. Exercise Mechanics. This Option may be exercised by delivery of an exercise notice, in the form attached as Exhibit A (the “Exercise Notice”), which shall state the election to exercise the Option, the number of Shares in respect of which the Option is being exercised (the “Exercised Shares”), and such other representations and agreements as may be required by the Company pursuant to the provisions of the Plan. The Exercise Notice shall be signed by Optionee and shall be delivered in person or by certified mail to the Secretary of the Company. The Exercise Notice must be accompanied by the payment of the full Option exercise price of such Shares. Exercise shall not be deemed to have occurred unless and until Optionee has delivered to the Company (or its authorized representative) an approved notice of exercise, full payment of the exercise price for the Shares being exercised and payment of any applicable withholding taxes in accordance with Section 8 below. Payment of the Option exercise price may be in cash (including check or wire transfer); through an approved cashless-brokered exercise program; with Shares (subject to the Company's discretion to withhold approval for such payment method at any time); through a cashless “net exercise” arrangement pursuant to which the Company will reduce the number of Shares issued upon exercise by the largest whole number of Shares having an aggregate fair market value that does not exceed the aggregate exercise price, provided the Company shall accept a cash or other payment from Optionee to the extent of any remaining balance of the exercise price not satisfied by such reduction in the number of whole Shares to be issued; or a combination thereof to the extent permissible under Applicable Law; provided, however, that any permitted method of payment shall be in strict compliance with all procedural rules established by the Board. 6. Termination of Employment. All rights of Optionee in this Option, to the extent that it has not previously become vested and been exercised, shall terminate upon Optionee's Termination of Employment except as set forth in this Section 6. The portion of the Option that relates to any Shares that were unvested and unexercisable as of the date of Optionee's Termination of Employment shall terminate and expire effective immediately upon such date. With respect to the vested and exercisable portion of the Option, and subject to the final sentence of this Section 6: (i) In the event of Termination of Employment other than as a result of Optionee's death or Disability, Optionee shall have three months from the date of such Termination of Employment to exercise the Option as to the Shares subject to the Option that were vested and exercisable as of the date of Termination of Employment; provided, however, that (A) if during any part of such three month period, the Option is not exercisable because the issuance of the Shares would violate the registration requirements under the Securities Act, the Option shall not expire until the Option shall have been exercisable for an aggregate of three months after the date of Termination of Employment (but in no event may the Option be exercised more than one year

Exhibit 10.9 6 2-10-2022 after the date of Termination of Employment), and (B) if during any part of such three month period, the Shares issued upon exercise of the Option may not be sold because Optionee has material nonpublic information regarding the Company or is otherwise subject to a trading blackout period under the Company’s Insider Trading Policy, the Option shall not expire until Optionee shall have had an aggregate of three months after the date of Termination of Employment during which Optionee can sell the Shares without being subject to such restrictions arising under insider trading laws or Company policy (but in no event may the Option be exercised more than one year after the date of Termination of Employment); (ii) In the event of Termination of Employment as a result of Optionee's Disability, Optionee shall have 12 months from the date of such Termination of Employment to exercise the Option as to the Shares subject to the Option that were vested and exercisable as of the date of Termination of Employment; and (iii) In the event of Termination of Employment as a result of Optionee’s death or in the event of Optionee’s death within three months following Optionee’s Termination of Employment, Optionee's estate, any person who acquired the right to exercise the Option by bequest or inheritance, or any person designated to exercise the Option upon Optionee's death shall have 12 months following Optionee’s death to exercise the Option as to the Shares subject to the Option that were vested and exercisable as of the date of Optionee’s death. Notwithstanding the above, in no event may an Option be exercised, even as to vested and otherwise exercisable Shares, after the Expiration Date set forth in Section 4 above. 7. Transferability. This Option is not transferable by Optionee otherwise than by will or the laws of descent and distribution, and is exercisable only by Optionee during Optionee’s lifetime. 8. Tax Matters. Regardless of any action the Company takes with respect to any or all income tax, social security, payroll tax, payment on account or other tax-related withholding (“Tax-Related Items”), Optionee acknowledges and agrees that the ultimate liability for all Tax- Related Items legally due by him or her is and remains Optionee's responsibility and that the Company (i) makes no representations nor undertakings regarding the treatment of any Tax- Related Items in connection with any aspect of this Option, including the grant, vesting or exercise of this Option, the subsequent sale of Shares acquired pursuant to such exercise and receipt of any dividends; and (ii) does not commit to structure the terms or the grant or any aspect of this Option to reduce or eliminate Optionee's liability for Tax-Related Items. If Optionee is subject to certain withholding requirements, then prior to the exercise of this Option, Optionee shall pay or make adequate arrangements satisfactory to the Company to withhold all applicable Tax-Related Items legally payable by Optionee from Optionee's wages or other cash compensation paid to Optionee by the Company or from proceeds of the sale of Shares. Alternatively, or in addition, if applicable and permissible under Applicable Laws, the Company may (but shall not be obligated to): (1) sell or arrange for the sale of Shares that Optionee acquires to meet the withholding obligation for Tax-Related Items, and/or (2) withhold in Shares to meet the withholding obligation for Tax-Related Items, provided that the Company only withholds the amount of Shares necessary to satisfy the minimum withholding amount (or such other amount as may be permitted while still avoiding classification of this Option as a liability for financial accounting purposes). In addition, if applicable, Optionee shall pay the Company

Exhibit 10.9 7 2-10-2022 any amount of Tax-Related Items that the Company may be required to withhold as a result of Optionee's participation in the Plan or Optionee's purchase of Shares that cannot be satisfied by the means previously described, and if Optionee does not otherwise so pay the Company, then the Company may withhold amounts from Optionee's cash compensation to satisfy such withholding obligation. The Company may refuse to honor the exercise and refuse to deliver the Shares if Optionee fails to comply with Optionee's obligations in connection with the Tax-Related Items (including if Optionee's cash compensation is not sufficient to satisfy such obligations). Although Optionee is being provided in the Plan prospectus a description of certain tax consequences of transactions related to the Option, Optionee remains responsible for all such tax consequences and the Company shall not be deemed to provide any individual tax advice with respect thereto. 9. Optionee Acknowledgements. By accepting the grant of this Option, Optionee acknowledges and agrees that the Plan is established voluntarily by the Company, it is discretionary in nature and may be modified, amended, suspended or terminated by the Company at any time unless otherwise provided in the Plan or this Agreement. Optionee acknowledges that all decisions with respect to future grants, if any, will be at the sole discretion of the Company. Optionee's participation in the Plan shall not create a right to his or her continued service as a Director. This Option shall not be part of calculating any severance, resignation, termination, redundancy, end-of-service payments, bonuses, long-service awards, pension or retirement benefits or similar payments insofar as permitted by law. In the event that Optionee is not an employee of the Company, this Option grant will not be interpreted to form an employment contract or relationship with the Company or any Subsidiary or Affiliate of the Company. Optionee acknowledges that the future value of the underlying Shares is unknown, may increase or decrease in the future, and cannot be predicted with certainty. In consideration of the grant of this Option, no claim or entitlement to compensation or damages shall arise from termination of this Option or diminution in value of this Option or Shares purchased through exercise of this Option resulting from Optionee's Termination of Employment by the Company (for any reason whatsoever and whether or not in breach of Applicable Laws). 10. Data Transfer. Optionee explicitly and unambiguously consents to the collection, use and transfer, in electronic or other form, of Optionee's personal data as described in this document by the Company for the purpose of implementing, administering and managing Optionee's participation in the Plan. Optionee understands that the Company holds certain personal information about Optionee, including, but not limited to, name, home address and telephone number, date of birth, social security number (or other identification number), salary, nationality, job title, any shares of stock or directorships held in the Company, details of all options or any other entitlement to shares of stock awarded, canceled, purchased, exercised, vested, unvested or outstanding in Optionee's favor for the purpose of implementing, managing and administering the Plan (“Data”). Optionee understands that the Data may be transferred to any third parties assisting in the implementation, administration and management of the Plan, including providing ancillary services related to stock plan administration. Optionee authorizes the recipients to receive, possess, use, retain and transfer the Data, in electronic or other form, for the purposes of implementing, administering and managing Optionee's participation in the Plan (including providing ancillary services related to stock plan administration), including any requisite transfer of such Data, as may be required to a broker or other third party with whom Optionee may elect to deposit any Shares acquired upon the exercise of this Option.

Exhibit 10.9 8 2-10-2022 11. Notices; Electronic Delivery and Acceptance. Any notices provided for in this Option or the Plan shall be given in writing and shall be deemed effectively given upon receipt or, in the case of notices delivered by the Company to Optionee, five (5) days after deposit in the United States mail, postage prepaid, addressed to Optionee at the last address Optionee provided to the Company. Notwithstanding the foregoing, the Company may, in its sole discretion, decide to deliver any documents related to participation in the Plan and this Option by electronic means or to request Optionee’s consent to participate in the Plan by electronic means. Optionee hereby consents to receive such documents by electronic delivery and, if requested, to agree to participate in the Plan through an on-line or electronic system established and maintained by the Company or another third party designated by the Company and agrees notice shall be provided upon posting to Optionee’s electronic account held by the Company or another third party designated by the Company. You hereby acknowledge that delivery, execution and acceptance of this or any other such documents by electronic means constitutes valid and effective delivery, execution and acceptance and shall be legally effective to create a valid and binding agreement. 12. Copies of Plan Materials. Optionee acknowledges that Optionee has received copies of the Plan and the Plan prospectus from the Company and agrees to receive stockholder information, including copies of any annual report, proxy statement and periodic report, from the Company's website at https://investor.seagen.com/overview/default.aspx (under the “Financial information” tab). Optionee acknowledges that copies of the Plan, Plan prospectus, Plan information and stockholder information are also available upon written or telephonic request to the Stock Plan Administrator. 13. Entire Agreement; Plan Controls. The Plan is incorporated herein by reference. The Plan and this Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Optionee with respect to the subject matter hereof, with the exception of any arrangement that would provide for vesting acceleration of this Option upon the terms and conditions set forth therein. This Agreement is governed by the laws of the state of Delaware. In the event of any conflict between the terms and provisions of the Plan and this Agreement, the Plan terms and provisions shall govern. Capitalized terms used but not defined in this Agreement or the Notice of Stock Option Grant attached to this Agreement have the meanings assigned to them in the Plan. Certain other important terms governing this Agreement are contained in the Plan. 14. Severability. If all or any part of this Agreement or the Plan is declared by any court or governmental authority to be unlawful or invalid, such unlawfulness or invalidity shall not invalidate any portion of this Agreement or the Plan not declared to be unlawful or invalid. Any Section of this Agreement (or part of such a Section) so declared to be unlawful or invalid shall, if possible, be construed in a manner which will give effect to the terms of such Section or part of a Section to the fullest extent possible while remaining lawful and valid. 15. Amendment. This Agreement may not be modified, amended or terminated except by an instrument in writing, signed by Optionee and by a duly authorized representative of the Company. Notwithstanding the foregoing, this Agreement may be amended solely by the Administrator by a writing which specifically states that it is amending this Agreement, so long as a copy of such amendment is delivered to Optionee, and provided that no such amendment adversely affecting Optionee’s rights hereunder may be made without Optionee’s written consent,

Exhibit 10.9 9 2-10-2022 except as otherwise provided in the Plan. Without limiting the foregoing, the Administrator reserves the right to change, by written notice to Optionee, the provisions of this Agreement in any way it may deem necessary or advisable to carry out the purpose of the grant as a result of any change in applicable laws or regulations or any future law, regulation, ruling, or judicial decision, provided that any such change shall be applicable only to rights relating to that portion of the Option which is then subject to restrictions as provided herein.

Exhibit 10.9 10 2-10-2022 By your signature and the signature of the Company’s representative below, you and the Company agree that this Option is granted under and governed by the terms and conditions of the Amended and Restated 2007 Equity Incentive Plan (the “Plan”) and this Stock Option Agreement (the “Agreement”). Optionee has reviewed the Plan and this Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Agreement and fully understands all provisions of the Plan and this Agreement. Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions relating to the Plan and this Agreement. OPTIONEE SEAGEN INC. By: «Name» Clay B. Siegall, Ph.D. President & CEO

Exhibit 10.9 11 2-10-2022 EXHIBIT A NOTICE OF EXERCISE To: Seagen Inc. Attn: Stock Option Administrator Subject: Notice of Intention to Exercise Stock Option This is official notice that the undersigned (“Optionee”) intends to exercise Optionee’s option to purchase __________ shares of Seagen Inc. Common Stock, under and pursuant to the Company’s Amended and Restated 2007 Equity Incentive Plan and the Stock Option Agreement dated _______________, as follows: Grant Number: Date of Purchase: Number of Shares: Purchase Price: Method of Payment of Purchase Price: Social Security No.: The shares should be issued as follows: Name: Address: Signed: Date:

EX-31.1

Exhibit 31.1

CERTIFICATIONS

I, Clay B. Siegall, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Seagen Inc.;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a.designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b.designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c.evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d.disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a.all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b.any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Clay B. Siegall
	Clay B. Siegall
	Chief Executive Officer
	(Principal Executive Officer)
Date:	April 28, 2022

EX-31.2

Exhibit 31.2

CERTIFICATIONS

I, Todd E. Simpson, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Seagen Inc.;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a.designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b.designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c.evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d.disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a.all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b.any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Todd E. Simpson
	Todd E. Simpson
	Chief Financial Officer
	(Principal Financial and Accounting Officer)
Date:	April 28, 2022

EX-32.1

Exhibit 32.1

SEAGEN INC.

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Seagen Inc. (the “Company”) on Form 10-Q for the quarter ended March 31, 2022, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Clay B. Siegall, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1.The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

By:	/s/ Clay B. Siegall
	Clay B. Siegall
	Chief Executive Officer
	(Principal Executive Officer)
Date:	April 28, 2022

This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Seagen Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

EX-32.2

Exhibit 32.2

SEAGEN INC.

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Seagen Inc. (the “Company”) on Form 10-Q for the quarter ended March 31, 2022, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Todd E. Simpson, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1.The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

By:	/s/ Todd E. Simpson
	Todd E. Simpson
	Chief Financial Officer
	(Principal Financial and Accounting Officer)
Date:	April 28, 2022

This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Seagen Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

XML

Cover Page - shares	3 Months Ended
	Mar. 31, 2022	Apr. 25, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	0-32405
Entity Registrant Name	SEAGEN INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	91-1874389
Entity Address	21823 30th Drive SE
Entity Address, City or Town	Bothell
Entity Address, State or Province	WA
Postal Zip Code	98021
City Area Code	425
Local Phone Number	527-4000
Title of 12(b) Security	Common Stock, par value $0.001
Trading Symbol	SGEN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		184,075,643
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001060736
Current Fiscal Year End Date	--12-31

XML

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 260,996	$ 424,834
Short-term investments	1,690,097	1,735,202
Accounts receivable, net	401,009	389,256
Inventories	275,747	200,663
Prepaid expenses and other current assets	143,406	119,239
Total current assets	2,771,255	2,869,194
Property and equipment, net	214,379	210,073
Operating lease right-of-use assets	54,937	57,889
Intangible assets, net	254,902	260,593
Goodwill	274,671	274,671
Other non-current assets	46,549	47,184
Total assets	3,616,693	3,719,604
Current liabilities:
Accounts payable	87,228	114,824
Accrued liabilities and other	444,066	454,030
Total current liabilities	531,294	568,854
Long-term liabilities:
Operating lease liabilities, long-term	53,552	56,665
Other long-term liabilities	33,380	28,946
Total long-term liabilities	86,932	85,611
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000 shares authorized; none issued	0	0
Common stock, $0.001 par value, 250,000 shares authorized; 183,892 shares issued and outstanding at March 31, 2022 and 183,381 shares issued and outstanding at December 31, 2021	184	183
Additional paid-in capital	4,678,392	4,607,816
Accumulated other comprehensive income	424	1,179
Accumulated deficit	(1,680,533)	(1,544,039)
Total stockholders’ equity	2,998,467	3,065,139
Total liabilities and stockholders’ equity	$ 3,616,693	$ 3,719,604

XML

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	183,892,000	183,381,000
Common stock, shares outstanding (in shares)	183,892,000	183,381,000

XML

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenues:
Total revenues	$ 426,460,000	$ 331,983,000
Costs and expenses:
Cost of sales	87,626,000	64,135,000
Research and development	297,659,000	230,426,000
Selling, general and administrative	174,225,000	159,842,000
Total costs and expenses	559,510,000	454,403,000
Loss from operations	(133,050,000)	(122,420,000)
Investment and other (loss) income , net	(2,190,000)	1,000,000
Loss before income taxes	(135,240,000)	(121,420,000)
Provision for income taxes	1,254,000	0
Net loss	$ (136,494,000)	$ (121,420,000)
Net loss per share - basic (in dollars per share)	$ (0.74)	$ (0.67)
Net loss per share - diluted (in dollars per share)	$ (0.74)	$ (0.67)
Shares used in computation of per share amounts - basic (in shares)	183,647	181,150
Shares used in computation of per share amounts - diluted (in shares)	183,647	181,150
Comprehensive loss:
Net loss	$ (136,494,000)	$ (121,420,000)
Other comprehensive loss:
Unrealized (loss) gain on securities available-for-sale, net of tax	(861,000)	166,000
Foreign currency translation gain (loss)	106,000	(237,000)
Total other comprehensive loss	(755,000)	(71,000)
Comprehensive loss	(137,249,000)	(121,491,000)
Net product sales
Revenues:
Total revenues	383,086,000	302,588,000
Royalty revenues
Revenues:
Total revenues	28,181,000	27,219,000
Collaboration and license agreement revenues
Revenues:
Total revenues	$ 15,193,000	$ 2,176,000

XML

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Accumulated other comprehensive income	Accumulated deficit
Beginning (in shares) at Dec. 31, 2020		180,902,000
Beginning at Dec. 31, 2020	$ 3,488,100	$ 181	$ 4,356,922	$ 565	$ (869,568)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(121,420)				(121,420)
Other comprehensive loss	(71)			(71)
Issuance of common stock for stock option exercises and employee stock purchase plan (in shares)		341,000
Issuance of common stock for stock option exercises and employee stock purchase plan	19,791		19,791
Restricted stock vested during the period, net (in shares)		80,000
Share-based compensation	38,224		38,224
Ending (in shares) at Mar. 31, 2021		181,323,000
Ending at Mar. 31, 2021	$ 3,424,624	$ 181	4,414,937	494	(990,988)
Beginning (in shares) at Dec. 31, 2021	183,381,000	183,381,000
Beginning at Dec. 31, 2021	$ 3,065,139	$ 183	4,607,816	1,179	(1,544,039)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(136,494)				(136,494)
Other comprehensive loss	(755)			(755)
Issuance of common stock for stock option exercises and employee stock purchase plan (in shares)		463,000
Issuance of common stock for stock option exercises and employee stock purchase plan	26,664	$ 1	26,663
Restricted stock vested during the period, net (in shares)		48,000
Share-based compensation	$ 43,913		43,913
Ending (in shares) at Mar. 31, 2022	183,892,000	183,892,000
Ending at Mar. 31, 2022	$ 2,998,467	$ 184	$ 4,678,392	$ 424	$ (1,680,533)

XML

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (136,494)	$ (121,420)
Adjustments to reconcile net loss to net cash used by operating activities
Share-based compensation	43,913	38,224
Depreciation	11,402	9,583
Amortization of intangible assets	5,691	5,694
Amortization of right-of-use assets	2,952	3,356
Amortization of premiums, accretion of discounts, and (gains) losses on debt securities	184	6,482
Losses (gains) on equity securities	2,779	(259)
Deferred income taxes	155	0
Changes in operating assets and liabilities
Accounts receivable, net	(11,753)	(10,840)
Inventories	(75,084)	(30,455)
Prepaid expenses and other assets	(24,523)	(27,763)
Lease liability	(5,158)	(4,239)
Other liabilities	(30,876)	6,311
Net cash used by operating activities	(216,812)	(125,326)
Investing activities:
Purchases of securities	(655,940)	(703,200)
Proceeds from maturities of securities	700,000	632,000
Purchases of property and equipment	(17,397)	(7,515)
Net cash provided (used) by investing activities	26,663	(78,715)
Financing activities:
Proceeds from exercise of stock options and employee stock purchase plan	26,664	19,791
Net cash provided by financing activities	26,664	19,791
Effect of exchange rate changes on cash and cash equivalents	(353)	(462)
Net decrease in cash and cash equivalents	(163,838)	(184,712)
Cash and cash equivalents at beginning of period	424,834	558,424
Cash and cash equivalents at end of period	$ 260,996	$ 373,712

XML

Summary of significant accounting policies

3 Months Ended

Mar. 31, 2022

Accounting Policies [Abstract]

Summary of significant accounting policies

Summary of significant accounting policies

Basis of presentation

The accompanying unaudited condensed consolidated financial statements reflect the accounts of Seagen Inc. and its wholly-owned subsidiaries (collectively “Seagen,” “we,” “our,” or “us”). All intercompany transactions and balances have been eliminated. Management has determined that we operate in one segment: the development and sale of pharmaceutical products on our own behalf or in collaboration with others. Substantially all of our assets and revenues are related to operations in the U.S.; however, we have multiple subsidiaries in foreign jurisdictions, including several subsidiaries in Europe.

The condensed consolidated balance sheet data as of December 31, 2021 were derived from audited financial statements not included in this quarterly report on Form 10-Q. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission, or SEC, and generally accepted accounting principles in the United States of America, or GAAP, for unaudited condensed consolidated financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments that, in the opinion of management, are necessary for a fair statement of our financial position and results of our operations as of and for the periods presented.

These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2021, as filed with the SEC.

The preparation of financial statements in accordance with GAAP requires us to make estimates, assumptions, and judgments that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates. The results of our operations for the three month period ended March 31, 2022 are not necessarily indicative of the results to be expected for the full year or any other interim period.

Non-cash activities

We had $8.2 million and $9.9 million of accrued capital expenditures as of March 31, 2022 and December 31, 2021, respectively. Accrued capital expenditures are treated as a non-cash investing activity and, accordingly, have not been included in the condensed consolidated statement of cash flows until such amounts have been paid in cash.

Investments

We hold certain equity securities which are reported at estimated fair value based on quoted market prices. Changes in the fair value of equity securities are recorded in income or loss. The cost of equity securities for purposes of computing gains and losses is based on the specific identification method.

We invest our available cash primarily in debt securities. These debt securities are classified as available-for-sale, which are reported at estimated fair value with unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains, realized losses and declines in the value of debt securities judged to be other-than-temporary are included in investment and other income (loss), net. The cost of debt securities for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Amortization of premiums and accretion of discounts on debt securities are included in investment and other income (loss), net. Interest and dividends earned are included in investment and other income (loss), net. Accrued interest receivable as of March 31, 2022 and December 31, 2021, were $0.6 million and $0.4 million, respectively, and were included in prepaid expenses and other current assets. We classify investments in debt securities maturing within one year of the reporting date, or where management’s intent is to use the investments to fund current operations or to make them available for current operations, as short-term investments.

If the estimated fair value of a debt security is below its carrying value, we evaluate whether it is more likely than not that we will sell the security before its anticipated recovery in market value and whether evidence indicating that the cost of the investment is recoverable within a reasonable period of time outweighs evidence to the contrary. We also evaluate whether or not we intend to sell the investment. If the impairment is considered to be other-than-temporary, the security is written down to its estimated fair value. In addition, we consider whether credit losses exist for any securities. A credit loss exists if the present value of cash flows expected to be collected is less than the amortized cost basis of the security. Other-than-temporary declines in estimated fair value and credit losses are included in investment and other income (loss), net.

Intangible assets, net

Our intangible assets are primarily comprised of acquired TUKYSA technology. The following table presents the balances of our finite-lived intangible assets for the periods presented:

(dollars in thousands)	March 31, 2022		December 31, 2021
Gross carrying value	$	305,650	$	305,650
Less: accumulated amortization	(50,748)		(45,057)
Total	$	254,902	$	260,593

The following table presents our amortization expense related to acquired TUKYSA technology costs, included in cost of sales in our condensed consolidated statements of comprehensive income (loss), for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Amortization expense	$	5,691	$	5,694

The weighted average remaining useful life of our finite-lived intangible assets was approximately 11 years as of March 31, 2022, and estimated future amortization expense related to acquired TUKYSA is $17.4 million for the nine months ending December 31, 2022, and TUKYSA technology costs is $23.1 million for each of the years ending December 31, 2023 through December 31, 2027.

Revenue recognition - Net product sales

We sell our products primarily through a limited number of specialty distributors and specialty pharmacies in the U.S, and to a lesser extent, internationally. The delivery of our products represents a single performance obligation for these transactions and we record net product sales at the point in time when control is transferred to the customer, which generally occurs upon receipt by the customer. The transaction price for net product sales represents the amount we expect to receive, which is net of estimated government-mandated rebates and chargebacks, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. We reflect these accruals as either a reduction in the related account receivable from the distributor or as an accrued liability, depending on the nature of the sales deduction. Sales deductions are based on management’s estimates that consider payor mix in target markets and experience to-date. These estimates involve a substantial degree of judgment.

Outside of the U.S., the transaction price for net product sales represents the amount we expect to receive, which is net of estimated discounts, estimated government mandated rebates, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. These estimates involve judgment in estimating net product sales.

U.S. government-mandated rebates and chargebacks: We have entered into a Medicaid Drug Rebate Agreement, or MDRA, with the Centers for Medicare & Medicaid Services. This agreement provides for a rebate based on covered purchases of our products. Medicaid rebates are invoiced to us by the various state Medicaid programs. We estimate Medicaid rebates using the expected value approach, based on a variety of factors, including payor mix and our experience to-date.

We have a Federal Supply Schedule, or FSS, agreement under which certain U.S. government purchasers receive a discount on eligible purchases of our products. In addition, we have entered into a Pharmaceutical Pricing Agreement with the Secretary of Health and Human Services, which enables certain entities that qualify for government pricing under the Public Health Services Act, or PHS, to receive discounts on their qualified purchases of our products. Under these agreements, eligible customers receive an applicable discount which is processed through the distributor as a chargeback. We estimate expected chargebacks for FSS and PHS purchases based on the expected value of each entity’s eligibility for the FSS and PHS programs. We also review historical rebate and chargeback information to further refine these estimates.

Distribution fees, product returns and other deductions: Our distributors charge a volume-based fee for distribution services that they perform for us. We allow for the return of product that is within a specified number of days of its expiration date or that is damaged. We estimate product returns based on our experience to-date using the expected value approach. We provide financial assistance to qualifying patients that are underinsured or cannot cover the cost of commercial coinsurance amounts through our patient support programs. Estimated contributions for commercial coinsurance under Seagen Secure are deducted from gross sales and are based on an analysis of expected plan utilization. These estimates are adjusted as necessary to reflect our actual experience.

Revenue recognition - Royalty revenues

Royalty revenues primarily reflect amounts earned under the ADCETRIS collaboration with Takeda Pharmaceutical Company Limited, or Takeda. These royalties include commercial sales-based milestones and sales royalties that relate predominantly to the license of intellectual property. Sales royalties are based on a percentage of Takeda’s net sales of ADCETRIS, with rates that range from the mid-teens to the mid-twenties based on annual net sales tiers. Takeda bears a portion of low single digit third-party royalty costs owed on its sales of ADCETRIS. This amount is included in royalty revenues. Amounts owed to our third-party licensors related to Takeda’s sales of ADCETRIS are recorded in cost of sales. These amounts are recognized in the period in which the related sales by Takeda occur. Royalty revenues also reflect amounts from Genentech, Inc., a member of the Roche Group, or Genentech, earned on net sales of Polivy, and amounts from GlaxoSmithKline earned on net sales of Blenrep.

Revenue recognition - Collaboration and license agreement revenues

We have collaboration and license agreements for our technology with a number of biotechnology and pharmaceutical companies. Under these agreements, we typically receive or are entitled to receive upfront cash payments and progress- and sales-dependent milestones for the achievement by our licensees of certain events, and annual maintenance fees and support fees for research and development services and materials provided under the agreements. We also are entitled to receive royalties on net sales of any resulting products incorporating our technology. Generally, our licensees are solely responsible for research, product development, manufacturing and commercialization of any product candidates under these collaborations, which includes the achievement of the potential milestones. Since we may not take a substantive role or control the research, development or commercialization of any products generated by some of our licensees, we may not be able to reasonably estimate when, if at all, any potential future milestone payments or royalties may be payable to us by our licensees. As such, the potential future milestone payments associated with certain of our collaboration and license agreements involve a substantial degree of uncertainty and risk that they may never be received.

Collaboration and license agreements are initially evaluated as to whether the intellectual property licenses granted by us represent distinct performance obligations. If they are determined to be distinct, the value of the intellectual property licenses would be recognized up-front while the research and development service fees would be recognized as the performance obligations are satisfied. Variable consideration is assessed at each reporting period as to whether it is not subject to future reversal of cumulative revenue and, therefore, should be included in the transaction price. Assessing the recognition of variable consideration requires significant judgment. If a contract includes a fixed or minimum amount of research and development support, this also would be included in the transaction price. Changes to collaboration and license agreements, such as the extensions of the research term or increasing the number of targets or technology covered under an existing agreement, are assessed for whether they represent a modification or should be accounted for as a new contract.

We have concluded that the license of intellectual property in certain collaboration and license agreements is not distinct from the perspective of our customers at the time of initial transfer, since we often do not license intellectual property without related technology transfer and research and development support services. Such evaluation requires significant judgment since it is made from the customer's perspective. Our performance obligations under our collaborations may include such things as providing intellectual property licenses, performing technology transfer, performing research and development consulting services, providing reagents, ADCs, and other materials, and notifying the customer of any enhancements to licensed technology or new technology that we discover, among others. We determined our performance obligations under certain collaboration and license agreements as evaluated at contract inception were not distinct and represented a single performance obligation. Upfront payments are amortized to revenue over the performance period. Upfront payment contract liabilities resulting from our collaborations do not represent a financing component as the payment is not financing the transfer of goods or services, and the technology underlying the licenses granted reflects research and development expenses already incurred by us. For agreements beyond the initial performance period, we have no remaining performance obligations. We may receive license maintenance fees and potential milestones and royalties based on collaborator development and regulatory progress, which are recorded in the period achieved in the case of milestones, and during the period of the related sales for royalties.

When no performance obligations are required of us, or following the completion of the performance obligation period, such amounts are recognized upon transfer of control of the goods or services to the customer. Generally, all amounts received or due other than sales-based milestones and royalties are classified as collaboration and license agreement revenues. Sales-based milestones and royalties are recognized as royalty revenue in the period the related sale occurred.

We generally invoice our collaborators and licensees on a monthly or quarterly basis, or upon the completion of the effort or achievement of a milestone, based on the terms of each agreement. Deferred revenue arises from amounts received in advance of the culmination of the earnings process and is recognized as revenue in future periods as performance obligations are satisfied. Deferred revenue expected to be recognized within the next twelve months is classified as a current liability.

XML

Revenue from contracts with customers

3 Months Ended

Mar. 31, 2022

Revenue from Contract with Customer [Abstract]

Revenue from contracts with customers

Revenue from contracts with customers

The following table presents our disaggregated revenue for the periods presented.

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
ADCETRIS	$	180,989	$	162,573
PADCEV	100,207		69,758
TUKYSA	90,475		70,257
TIVDAK	11,415		—
Net product sales	$	383,086	$	302,588
Royalty revenues	$	28,181	$	27,219
Collaboration and license agreement revenues	$	15,193	$	2,176
Total revenues	$	426,460	$	331,983

XML

Leases

3 Months Ended

Mar. 31, 2022

Leases [Abstract]

Leases

Leases

We have operating leases for our office and laboratory facilities with terms that expire from 2022 through 2029. We did not record any right-of-use assets in exchange for lease liabilities during the three months ended March 31, 2022 and 2021. All of our significant leases include options for us to extend the lease term. None of our options to extend the rental term of any existing leases were considered reasonably certain as of March 31, 2022.

In June 2021, we entered into a lease agreement for an approximately 258,000 square feet building complex to be constructed by the landlord on approximately 20.5 acres of land in Everett, Washington. We intend to use the building for future manufacturing, laboratory, and office space. Under the terms of the lease, base rent is payable at an initial rate of $4.0 million per year, subject to annual escalations of 3% during the initial term of 20 years. The lease commences on the date when construction and delivery of the building shell and related improvements by the landlord have been substantially completed. We will record a lease liability and right-of-use assets on our condensed consolidated balance sheet on the lease commencement date, which has not commenced as of March 31, 2022. We have an option to renew the lease for two additional terms of ten years each. In addition, we have an option to purchase the premises in the future.

Supplemental operating lease information was as follows:

	Three Months Ended March 31,
(dollars in thousands)	2022			2021
Operating lease cost	$	4,195		$	4,014
Variable lease cost	1,072			987
Total lease cost	$	5,267		$	5,001
Cash paid for amounts included in measurement of lease liabilities	$	4,553		$	3,858
	As of March 31,
	2022			2021
Weighted average remaining lease term	5.7 years			6.0 years
Weighted average discount rate	5.0		%	5.2		%

Operating lease liabilities were recorded in the following captions of our condensed consolidated balance sheet as follows:

(dollars in thousands)	March 31, 2022		December 31, 2021
Accrued liabilities and other	$	13,721	$	13,905
Operating lease liabilities, long-term	53,552		56,665
Total	$	67,273	$	70,570

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Net loss per share

3 Months Ended

Mar. 31, 2022

Earnings Per Share [Abstract]

Net loss per share

Net loss per share

Basic net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted average number of common shares and dilutive potential common shares outstanding during the period. Potentially dilutive common shares include incremental common shares issuable upon the vesting of unvested restricted stock units and the exercise of outstanding stock options, calculated using the treasury stock method.

We excluded the potential shares of common stock from the computation of diluted net income (loss) per share because their effect would have been antidilutive. The following table presents the weighted average number of shares that have been excluded for all periods presented:

	Three Months Ended March 31,
(in thousands)	2022	2021
Stock options and RSUs	10,333	10,468

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Fair value

3 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Fair value

Fair value

We have certain assets that are measured at fair value on a recurring basis according to a fair value hierarchy that prioritizes the inputs, assumptions and valuation techniques used to measure fair value. The three levels of the fair value hierarchy are:

Level 1:	Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.
Level 2:	Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly.
Level 3:	Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

The determination of a financial instrument’s level within the fair value hierarchy is based on an assessment of the lowest level of any input that is significant to the fair value measurement. We consider observable data to be market data which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market.

The fair value hierarchy of assets carried at fair value and measured on a recurring basis was as follows: 

	Fair value measurement using:
(dollars in thousands)	Quoted prices in active markets for identical assets (Level 1)		Other observable inputs (Level 2)		Significant unobservable inputs (Level 3)		Total
March 31, 2022
Short-term investments—U.S. Treasury securities	$	1,690,097	$	—	$	—	$	1,690,097
Other non-current assets—equity securities	11,230		—		—		11,230
Total	$	1,701,327	$	—	$	—	$	1,701,327
December 31, 2021
Short-term investments—U.S. Treasury securities	$	1,735,202	$	—	$	—	$	1,735,202
Other non-current assets—equity securities	14,009		—		—		14,009
Total	$	1,749,211	$	—	$	—	$	1,749,211

Our short-term debt investments portfolio only contains investments in U.S. Treasury and other U.S. government-backed securities. We review our portfolio based on the underlying risk profile of the securities and have a zero loss expectation for these investments. We also regularly review the securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. During the three months ended March 31, 2022 and 2021, we recognized no year-to-date credit loss related to our short- and long-term investments, and had no allowance for credit loss recorded as of March 31, 2022 or December 31, 2021.

Our debt securities consisted of the following:

(dollars in thousands)	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
March 31, 2022
U.S. Treasury securities	$	1,691,144	$	1	$	(1,048)	$	1,690,097
Contractual maturities (at date of purchase):
Due in one year or less	$	1,691,144					$	1,690,097
December 31, 2021
U.S. Treasury securities	$	1,735,388	$	12	$	(198)	$	1,735,202
Contractual maturities (at date of purchase):
Due in one year or less	$	1,635,307					$	1,635,118
Due in one to two years	100,081						100,084
Total	$	1,735,388					$	1,735,202

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Investment and other income (loss), net

3 Months Ended

Mar. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Investment and other income (loss), net

Investment and other income (loss), net

Investment and other income (loss), net consisted of the following:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
(Loss) gain on equity securities	$	(2,779)	$	259
Investment and other income, net	589		741
Total investment and other (loss) income, net	$	(2,190)	$	1,000

(Loss) gain on equity securities includes the realized and unrealized holding gains and losses on our equity securities. At times, we hold equity investments in certain companies acquired in relation to a strategic partnership. Shares held at the end of reporting periods are marked to market in our condensed consolidated financial statements, which can result in unrealized gains and losses.

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Inventories

3 Months Ended

Mar. 31, 2022

Inventory Disclosure [Abstract]

Inventories

Inventories

Inventories consisted of the following:

(dollars in thousands)	March 31, 2022		December 31, 2021
Raw materials	$	13,491	$	12,181
Work in process	216,663		152,635
Finished goods	45,593		35,847
Total	$	275,747	$	200,663

We capitalize our commercial inventory costs. Inventory that is deployed into clinical, research or development use is charged to research and development expense when it is no longer available for use in commercial sales.

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Accrued liabilities

3 Months Ended

Mar. 31, 2022

Payables and Accruals [Abstract]

Accrued liabilities

Accrued liabilities

Accrued liabilities consisted of the following: 

(dollars in thousands)	March 31, 2022		December 31, 2021
Employee compensation and benefits	$	83,389	$	139,052
Clinical trial and related costs	146,985		122,468
Contract manufacturing	27,147		21,867
Gross-to-net deductions and third-party royalties	88,973		81,316
Other	97,572		89,327
Total	$	444,066	$	454,030

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Share-based compensation

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Share-based compensation

Share-based compensation

The following table presents our total share-based compensation expense for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Research and development	$	23,076	$	16,964
Selling, general and administrative	20,837		21,260
Total share-based compensation expense	$	43,913	$	38,224

As of March 31, 2022, there was $137.3 million of unrecognized compensation cost related to unvested options and restricted stock unit awards, excluding our LTIPs and performance-based awards, net of forfeitures. The estimated unrecognized compensation expense related to our performance-based LTIPs was approximately $79 million as of March 31, 2022.

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Income taxes

3 Months Ended

Mar. 31, 2022

Income Tax Disclosure [Abstract]

Income taxes

Income taxes

For the three months ended March 31, 2022, we had taxable profits in the U.S. as a result of amendments to IRC Section 174, which took effect January 1, 2022 pursuant to the 2017 Tax Cuts and Jobs Act. We recorded an income tax provision of $1.3 million, primarily related to estimated state tax liabilities for which there were limitations on the use of existing state tax carryforwards. We had existing federal tax carryforwards sufficient to offset any federal liability. Our income tax provision also reflected taxable profits in foreign jurisdictions. Our effective tax rate of approximately 0.9% differed from the federal statutory rate primarily because we have provided a valuation allowance against substantially all our deferred tax assets.

For the three months ended March 31, 2021, we did not record any income tax provision.

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Legal matters

3 Months Ended

Mar. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Legal matters

Legal matters

We are engaged in multiple legal disputes with Daiichi Sankyo Co. Ltd., or Daiichi Sankyo.

Dispute over ownership of intellectual property

We are in a dispute with Daiichi Sankyo regarding the ownership of certain technology used by Daiichi Sankyo in its cancer drug ENHERTU and certain product candidates. We believe that the linker and other ADC technology used in ENHERTU and these drug candidates are improvements to our ADC technology, the ownership of which we contend was assigned to us under the terms of a 2008 collaboration agreement between us and Daiichi Sankyo. On November 12, 2019, we submitted an arbitration demand to the American Arbitration Association seeking, among other remedies, a declaration that we are the owner of the intellectual property rights under dispute, monetary damages, and a running royalty. On April 27, 2020, the arbitrator confirmed the dispute should be resolved in arbitration. The arbitration hearing was conducted in June 2021. Recently, the arbitration hearing record was reopened by the arbitrator to consider additional evidence. A decision in the arbitration case is expected in mid-2022.

On November 4, 2019, Daiichi Sankyo filed a declaratory judgment action in the United States District Court for the District of Delaware, alleging that we are not entitled to the intellectual property rights under dispute, in an attempt to have the dispute adjudicated in federal court. The case has been stayed and administratively closed by court order.

Patent infringement

On October 19, 2020, we filed a complaint in the United States District Court for the Eastern District of Texas to commence an action for infringement of our U.S. Patent No. 10,808,039, or the '039 Patent, by Daiichi Sankyo’s importation into, offer for sale, sale, and use in the United States of the cancer drug ENHERTU. The remedies sought in this action include, among other remedies, a judgment that Daiichi Sankyo infringed one or more valid and enforceable claims of the '039 Patent, monetary damages and a running royalty.

Daiichi Sankyo (as well as Daiichi Sankyo, Inc. and AstraZeneca Pharmaceuticals, LP, or AstraZeneca) subsequently filed an action on November 13, 2020 in the U.S. District Court for the District of Delaware seeking a declaratory judgment that ENHERTU does not infringe the ‘039 Patent. The Delaware action has been stayed by court order.

Daiichi Sankyo, Inc. and AstraZeneca also filed two petitions for post-grant review on December 23, 2020 and January 22, 2021 with the U.S. Patent and Trademark Office, or USPTO, seeking to have claims of the ‘039 Patent cancelled as unpatentable. On June 24, 2021, the USPTO issued a decision denying both petitions for post-grant review. On April 7, 2022, the Patent Trial and Appeal Board of the USPTO granted a request on rehearing and instituted two post-grant review proceedings.

On April 8, 2022, a jury in the United States District Court for the Eastern District of Texas found that Daiichi Sankyo willfully infringed the asserted claims of the '039 Patent with its ENHERTU product, and also found that the asserted claims were not invalid. The jury further awarded damages of $41.8 million for infringement from October 20, 2020 through March 31, 2022. We will record an amount of awarded damages in our condensed consolidated financial statements when we have determined the payment to be realized or realizable under ASC 450. We intend to request a royalty on Daiichi Sankyo's future sales of ENHERTU in the United States through November 5, 2024, as well as enhanced damages, attorney fees and costs.

As a result of these disputes, we have incurred and will continue to incur litigation expenses. In addition, from time to time, we may become involved in other lawsuits, claims and proceedings relating to the conduct of our business, including those pertaining to the defense and enforcement of our patent or other intellectual property rights and our contractual rights. These proceedings are costly and time consuming, and they may subject us to claims which may result in liabilities or require us to take or refrain from certain actions. Additionally, successful challenges to our patent or other intellectual property rights through these proceedings could result in a loss of rights in the relevant jurisdiction and may allow third parties to use our proprietary technologies without a license from us or our collaborators.

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Summary of significant accounting policies (Policies)

3 Months Ended

Mar. 31, 2022

Accounting Policies [Abstract]

Basis of presentation

Basis of presentation

The accompanying unaudited condensed consolidated financial statements reflect the accounts of Seagen Inc. and its wholly-owned subsidiaries (collectively “Seagen,” “we,” “our,” or “us”). All intercompany transactions and balances have been eliminated. Management has determined that we operate in one segment: the development and sale of pharmaceutical products on our own behalf or in collaboration with others. Substantially all of our assets and revenues are related to operations in the U.S.; however, we have multiple subsidiaries in foreign jurisdictions, including several subsidiaries in Europe.

The condensed consolidated balance sheet data as of December 31, 2021 were derived from audited financial statements not included in this quarterly report on Form 10-Q. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission, or SEC, and generally accepted accounting principles in the United States of America, or GAAP, for unaudited condensed consolidated financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments that, in the opinion of management, are necessary for a fair statement of our financial position and results of our operations as of and for the periods presented.

These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2021, as filed with the SEC.

The preparation of financial statements in accordance with GAAP requires us to make estimates, assumptions, and judgments that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates. The results of our operations for the three month period ended March 31, 2022 are not necessarily indicative of the results to be expected for the full year or any other interim period.

Non-cash activities

Non-cash activitiesWe had $8.2 million and $9.9 million of accrued capital expenditures as of March 31, 2022 and December 31, 2021, respectively. Accrued capital expenditures are treated as a non-cash investing activity and, accordingly, have not been included in the condensed consolidated statement of cash flows until such amounts have been paid in cash.

Investments

Investments

We hold certain equity securities which are reported at estimated fair value based on quoted market prices. Changes in the fair value of equity securities are recorded in income or loss. The cost of equity securities for purposes of computing gains and losses is based on the specific identification method.

We invest our available cash primarily in debt securities. These debt securities are classified as available-for-sale, which are reported at estimated fair value with unrealized gains and losses included in accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains, realized losses and declines in the value of debt securities judged to be other-than-temporary are included in investment and other income (loss), net. The cost of debt securities for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Amortization of premiums and accretion of discounts on debt securities are included in investment and other income (loss), net. Interest and dividends earned are included in investment and other income (loss), net. Accrued interest receivable as of March 31, 2022 and December 31, 2021, were $0.6 million and $0.4 million, respectively, and were included in prepaid expenses and other current assets. We classify investments in debt securities maturing within one year of the reporting date, or where management’s intent is to use the investments to fund current operations or to make them available for current operations, as short-term investments.

If the estimated fair value of a debt security is below its carrying value, we evaluate whether it is more likely than not that we will sell the security before its anticipated recovery in market value and whether evidence indicating that the cost of the investment is recoverable within a reasonable period of time outweighs evidence to the contrary. We also evaluate whether or not we intend to sell the investment. If the impairment is considered to be other-than-temporary, the security is written down to its estimated fair value. In addition, we consider whether credit losses exist for any securities. A credit loss exists if the present value of cash flows expected to be collected is less than the amortized cost basis of the security. Other-than-temporary declines in estimated fair value and credit losses are included in investment and other income (loss), net.

Intangible assets, net

Intangible assets, netOur intangible assets are primarily comprised of acquired TUKYSA technology.

Revenue recognition - Net product sales

Revenue recognition - Net product sales

We sell our products primarily through a limited number of specialty distributors and specialty pharmacies in the U.S, and to a lesser extent, internationally. The delivery of our products represents a single performance obligation for these transactions and we record net product sales at the point in time when control is transferred to the customer, which generally occurs upon receipt by the customer. The transaction price for net product sales represents the amount we expect to receive, which is net of estimated government-mandated rebates and chargebacks, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. We reflect these accruals as either a reduction in the related account receivable from the distributor or as an accrued liability, depending on the nature of the sales deduction. Sales deductions are based on management’s estimates that consider payor mix in target markets and experience to-date. These estimates involve a substantial degree of judgment.

Outside of the U.S., the transaction price for net product sales represents the amount we expect to receive, which is net of estimated discounts, estimated government mandated rebates, distribution fees, estimated product returns, and other deductions. Accruals are established for these deductions, and actual amounts incurred are offset against applicable accruals. These estimates involve judgment in estimating net product sales.

U.S. government-mandated rebates and chargebacks: We have entered into a Medicaid Drug Rebate Agreement, or MDRA, with the Centers for Medicare & Medicaid Services. This agreement provides for a rebate based on covered purchases of our products. Medicaid rebates are invoiced to us by the various state Medicaid programs. We estimate Medicaid rebates using the expected value approach, based on a variety of factors, including payor mix and our experience to-date.

We have a Federal Supply Schedule, or FSS, agreement under which certain U.S. government purchasers receive a discount on eligible purchases of our products. In addition, we have entered into a Pharmaceutical Pricing Agreement with the Secretary of Health and Human Services, which enables certain entities that qualify for government pricing under the Public Health Services Act, or PHS, to receive discounts on their qualified purchases of our products. Under these agreements, eligible customers receive an applicable discount which is processed through the distributor as a chargeback. We estimate expected chargebacks for FSS and PHS purchases based on the expected value of each entity’s eligibility for the FSS and PHS programs. We also review historical rebate and chargeback information to further refine these estimates.

Distribution fees, product returns and other deductions: Our distributors charge a volume-based fee for distribution services that they perform for us. We allow for the return of product that is within a specified number of days of its expiration date or that is damaged. We estimate product returns based on our experience to-date using the expected value approach. We provide financial assistance to qualifying patients that are underinsured or cannot cover the cost of commercial coinsurance amounts through our patient support programs. Estimated contributions for commercial coinsurance under Seagen Secure are deducted from gross sales and are based on an analysis of expected plan utilization. These estimates are adjusted as necessary to reflect our actual experience.

Revenue recognition - Royalty revenues

Royalty revenues primarily reflect amounts earned under the ADCETRIS collaboration with Takeda Pharmaceutical Company Limited, or Takeda. These royalties include commercial sales-based milestones and sales royalties that relate predominantly to the license of intellectual property. Sales royalties are based on a percentage of Takeda’s net sales of ADCETRIS, with rates that range from the mid-teens to the mid-twenties based on annual net sales tiers. Takeda bears a portion of low single digit third-party royalty costs owed on its sales of ADCETRIS. This amount is included in royalty revenues. Amounts owed to our third-party licensors related to Takeda’s sales of ADCETRIS are recorded in cost of sales. These amounts are recognized in the period in which the related sales by Takeda occur. Royalty revenues also reflect amounts from Genentech, Inc., a member of the Roche Group, or Genentech, earned on net sales of Polivy, and amounts from GlaxoSmithKline earned on net sales of Blenrep.

Revenue recognition - Collaboration and license agreement revenues

We have collaboration and license agreements for our technology with a number of biotechnology and pharmaceutical companies. Under these agreements, we typically receive or are entitled to receive upfront cash payments and progress- and sales-dependent milestones for the achievement by our licensees of certain events, and annual maintenance fees and support fees for research and development services and materials provided under the agreements. We also are entitled to receive royalties on net sales of any resulting products incorporating our technology. Generally, our licensees are solely responsible for research, product development, manufacturing and commercialization of any product candidates under these collaborations, which includes the achievement of the potential milestones. Since we may not take a substantive role or control the research, development or commercialization of any products generated by some of our licensees, we may not be able to reasonably estimate when, if at all, any potential future milestone payments or royalties may be payable to us by our licensees. As such, the potential future milestone payments associated with certain of our collaboration and license agreements involve a substantial degree of uncertainty and risk that they may never be received.

Collaboration and license agreements are initially evaluated as to whether the intellectual property licenses granted by us represent distinct performance obligations. If they are determined to be distinct, the value of the intellectual property licenses would be recognized up-front while the research and development service fees would be recognized as the performance obligations are satisfied. Variable consideration is assessed at each reporting period as to whether it is not subject to future reversal of cumulative revenue and, therefore, should be included in the transaction price. Assessing the recognition of variable consideration requires significant judgment. If a contract includes a fixed or minimum amount of research and development support, this also would be included in the transaction price. Changes to collaboration and license agreements, such as the extensions of the research term or increasing the number of targets or technology covered under an existing agreement, are assessed for whether they represent a modification or should be accounted for as a new contract.

We have concluded that the license of intellectual property in certain collaboration and license agreements is not distinct from the perspective of our customers at the time of initial transfer, since we often do not license intellectual property without related technology transfer and research and development support services. Such evaluation requires significant judgment since it is made from the customer's perspective. Our performance obligations under our collaborations may include such things as providing intellectual property licenses, performing technology transfer, performing research and development consulting services, providing reagents, ADCs, and other materials, and notifying the customer of any enhancements to licensed technology or new technology that we discover, among others. We determined our performance obligations under certain collaboration and license agreements as evaluated at contract inception were not distinct and represented a single performance obligation. Upfront payments are amortized to revenue over the performance period. Upfront payment contract liabilities resulting from our collaborations do not represent a financing component as the payment is not financing the transfer of goods or services, and the technology underlying the licenses granted reflects research and development expenses already incurred by us. For agreements beyond the initial performance period, we have no remaining performance obligations. We may receive license maintenance fees and potential milestones and royalties based on collaborator development and regulatory progress, which are recorded in the period achieved in the case of milestones, and during the period of the related sales for royalties.

When no performance obligations are required of us, or following the completion of the performance obligation period, such amounts are recognized upon transfer of control of the goods or services to the customer. Generally, all amounts received or due other than sales-based milestones and royalties are classified as collaboration and license agreement revenues. Sales-based milestones and royalties are recognized as royalty revenue in the period the related sale occurred.

We generally invoice our collaborators and licensees on a monthly or quarterly basis, or upon the completion of the effort or achievement of a milestone, based on the terms of each agreement. Deferred revenue arises from amounts received in advance of the culmination of the earnings process and is recognized as revenue in future periods as performance obligations are satisfied. Deferred revenue expected to be recognized within the next twelve months is classified as a current liability.

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Summary of significant accounting policies (Tables)

3 Months Ended

Mar. 31, 2022

Accounting Policies [Abstract]

Schedule of finite-lived intangible assets

The following table presents the balances of our finite-lived intangible assets for the periods presented:

(dollars in thousands)	March 31, 2022		December 31, 2021
Gross carrying value	$	305,650	$	305,650
Less: accumulated amortization	(50,748)		(45,057)
Total	$	254,902	$	260,593

Schedule of amortization expense

The following table presents our amortization expense related to acquired TUKYSA technology costs, included in cost of sales in our condensed consolidated statements of comprehensive income (loss), for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Amortization expense	$	5,691	$	5,694

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Revenue from contracts with customers (Tables)

3 Months Ended

Mar. 31, 2022

Revenue from Contract with Customer [Abstract]

Summary of Collaboration and License Agreement Revenues by Collaborator

The following table presents our disaggregated revenue for the periods presented.

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
ADCETRIS	$	180,989	$	162,573
PADCEV	100,207		69,758
TUKYSA	90,475		70,257
TIVDAK	11,415		—
Net product sales	$	383,086	$	302,588
Royalty revenues	$	28,181	$	27,219
Collaboration and license agreement revenues	$	15,193	$	2,176
Total revenues	$	426,460	$	331,983

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Leases (Tables)

3 Months Ended

Mar. 31, 2022

Leases [Abstract]

Summary of Supplemental Operating Lease Information

Supplemental operating lease information was as follows:

	Three Months Ended March 31,
(dollars in thousands)	2022			2021
Operating lease cost	$	4,195		$	4,014
Variable lease cost	1,072			987
Total lease cost	$	5,267		$	5,001
Cash paid for amounts included in measurement of lease liabilities	$	4,553		$	3,858
	As of March 31,
	2022			2021
Weighted average remaining lease term	5.7 years			6.0 years
Weighted average discount rate	5.0		%	5.2		%

Summary of Operating Lease Assets and Liabilities

Operating lease liabilities were recorded in the following captions of our condensed consolidated balance sheet as follows:

(dollars in thousands)	March 31, 2022		December 31, 2021
Accrued liabilities and other	$	13,721	$	13,905
Operating lease liabilities, long-term	53,552		56,665
Total	$	67,273	$	70,570

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Net (loss) income per share (Tables)

3 Months Ended

Mar. 31, 2022

Earnings Per Share [Abstract]

Schedule of Weighted Average Number of Shares

The following table presents the weighted average number of shares that have been excluded for all periods presented:

	Three Months Ended March 31,
(in thousands)	2022	2021
Stock options and RSUs	10,333	10,468

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Fair value (Tables)

3 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Summary of Fair Value Hierarchy of Assets Carried at Fair Value and Measured on a Recurring Basis

The fair value hierarchy of assets carried at fair value and measured on a recurring basis was as follows: 

	Fair value measurement using:
(dollars in thousands)	Quoted prices in active markets for identical assets (Level 1)		Other observable inputs (Level 2)		Significant unobservable inputs (Level 3)		Total
March 31, 2022
Short-term investments—U.S. Treasury securities	$	1,690,097	$	—	$	—	$	1,690,097
Other non-current assets—equity securities	11,230		—		—		11,230
Total	$	1,701,327	$	—	$	—	$	1,701,327
December 31, 2021
Short-term investments—U.S. Treasury securities	$	1,735,202	$	—	$	—	$	1,735,202
Other non-current assets—equity securities	14,009		—		—		14,009
Total	$	1,749,211	$	—	$	—	$	1,749,211

Summary of Debt Securities

Our debt securities consisted of the following:

(dollars in thousands)	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
March 31, 2022
U.S. Treasury securities	$	1,691,144	$	1	$	(1,048)	$	1,690,097
Contractual maturities (at date of purchase):
Due in one year or less	$	1,691,144					$	1,690,097
December 31, 2021
U.S. Treasury securities	$	1,735,388	$	12	$	(198)	$	1,735,202
Contractual maturities (at date of purchase):
Due in one year or less	$	1,635,307					$	1,635,118
Due in one to two years	100,081						100,084
Total	$	1,735,388					$	1,735,202

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Investment and other income (loss), net (Tables)

3 Months Ended

Mar. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Schedule of Investment and Other Income, Net

Investment and other income (loss), net consisted of the following:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
(Loss) gain on equity securities	$	(2,779)	$	259
Investment and other income, net	589		741
Total investment and other (loss) income, net	$	(2,190)	$	1,000

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Inventories (Tables)

3 Months Ended

Mar. 31, 2022

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories consisted of the following:

(dollars in thousands)	March 31, 2022		December 31, 2021
Raw materials	$	13,491	$	12,181
Work in process	216,663		152,635
Finished goods	45,593		35,847
Total	$	275,747	$	200,663

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Accrued liabilities (Tables)

3 Months Ended

Mar. 31, 2022

Payables and Accruals [Abstract]

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following: 

(dollars in thousands)	March 31, 2022		December 31, 2021
Employee compensation and benefits	$	83,389	$	139,052
Clinical trial and related costs	146,985		122,468
Contract manufacturing	27,147		21,867
Gross-to-net deductions and third-party royalties	88,973		81,316
Other	97,572		89,327
Total	$	444,066	$	454,030

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Share-based compensation (Tables)

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Schedule of Share-based Compensation

The following table presents our total share-based compensation expense for the periods presented:

	Three Months Ended March 31,
(dollars in thousands)	2022		2021
Research and development	$	23,076	$	16,964
Selling, general and administrative	20,837		21,260
Total share-based compensation expense	$	43,913	$	38,224

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Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of reporting segments | segment	1
Accrued capital expenditures	$ 8.2	$ 9.9
Accrued interest receivable	0.6	$ 0.4
Estimated future amortization expense, remainder of fiscal year	17.4
Estimated future amortization expense, 2023	23.1
Estimated future amortization expense, 2024	23.1
Estimated future amortization expense, 2025	23.1
Estimated future amortization expense, 2026	23.1
Estimated future amortization expense, 2027	$ 23.1
Weighted Average
Summary Of Significant Accounting Policies [Line Items]
Intangible asset useful life	11 years

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Summary of significant accounting policies - Finite-lived intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Gross carrying value	$ 305,650	$ 305,650
Less: accumulated amortization	(50,748)	(45,057)
Total	$ 254,902	$ 260,593

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Summary of significant accounting policies - Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accounting Policies [Abstract]
Amortization expense	$ 5,691	$ 5,694

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Revenue from contracts with customers - Summary of Collaboration and License Agreement Revenues by Collaborator (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	$ 426,460	$ 331,983
Net product sales
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	383,086	302,588
Net product sales | ADCETRIS
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	180,989	162,573
Net product sales | PADCEV
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	100,207	69,758
Net product sales | TUKYSA
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	90,475	70,257
Net product sales | TIVDAK
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	11,415	0
Royalty revenues
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	28,181	27,219
Collaboration and license agreement revenues
Disaggregation of Revenue [Line Items]
Collaboration and license agreement revenues	$ 15,193	$ 2,176

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Leases - Additional Information (Details) ft² in Thousands, $ in Thousands	1 Months Ended	3 Months Ended
	Jun. 30, 2021 USD ($) ft² a term	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Leases [Abstract]
Lease agreement, rented area | ft²	258
Rentable building and complex constructed (in acres) | a	20.5
Initial rate | $	$ 4,000	$ 4,553	$ 3,858
Annual escalations	3.00%
Initial term	20 years
Option to extend | term	2
Renewal term	10 years

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Leases - Lease Cost (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2022	Mar. 31, 2021
Leases [Abstract]
Operating lease cost		$ 4,195	$ 4,014
Variable lease cost		1,072	987
Total lease cost		5,267	5,001
Cash paid for amounts included in measurement of lease liabilities	$ 4,000	$ 4,553	$ 3,858
Weighted average remaining lease term		5 years 8 months 12 days	6 years
Weighted average discount rate		5.00%	5.20%

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Leases - Summary of Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Accrued liabilities and other	$ 13,721	$ 13,905
Accrued liabilities and other extensible list	Accrued liabilities and other	Accrued liabilities and other
Operating lease liabilities, long-term	$ 53,552	$ 56,665
Total	$ 67,273	$ 70,570

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Net loss per share - Additional Information (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Stock options and RSUs (in shares)	10,333	10,468

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Fair value - Summary of Fair Value Hierarchy of Assets Carried at Fair Value and Measured on a Recurring Basis (Details) - Fair Value Measurements Recurring - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 1,701,327	$ 1,749,211
US Treasury Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,690,097	1,735,202
Equity Securities | Other Non-current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	11,230	14,009
Quoted prices in active markets for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,701,327	1,749,211
Quoted prices in active markets for identical assets (Level 1) | US Treasury Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,690,097	1,735,202
Quoted prices in active markets for identical assets (Level 1) | Equity Securities | Other Non-current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	11,230	14,009
Other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Other observable inputs (Level 2) | US Treasury Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Other observable inputs (Level 2) | Equity Securities | Other Non-current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Significant unobservable inputs (Level 3) | US Treasury Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Significant unobservable inputs (Level 3) | Equity Securities | Other Non-current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 0	$ 0

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Fair value - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Credit loss	$ 0	$ 0
Allowance for credit loss	$ 0		$ 0

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Fair value - Summary of Debt Securities (Details) - US Treasury Securities - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 1,691,144	$ 1,735,388
Gross unrealized gains	1	12
Gross unrealized losses	(1,048)	(198)
Fair value	1,690,097	1,735,202
Debt securities, due in one year or less, amortized cost	1,691,144	1,635,307
Debt securities, due in one year or less, fair value	$ 1,690,097	1,635,118
Debt securities, due in one to two years, amortized cost		100,081
Debt securities, due in one to two years, fair value		$ 100,084

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Investment and other income (loss), net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
(Loss) gain on equity securities	$ (2,779)	$ 259
Investment and other income, net	589	741
Total investment and other (loss) income, net	$ (2,190)	$ 1,000

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Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Inventory Disclosure [Abstract]
Raw materials	$ 13,491	$ 12,181
Work in process	216,663	152,635
Finished goods	45,593	35,847
Total	$ 275,747	$ 200,663

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Accrued liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Employee compensation and benefits	$ 83,389	$ 139,052
Clinical trial and related costs	146,985	122,468
Contract manufacturing	27,147	21,867
Gross-to-net deductions and third-party royalties	88,973	81,316
Other	97,572	89,327
Accrued liabilities and other	$ 444,066	$ 454,030

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Share-based compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 43,913	$ 38,224
Unrecognized compensation cost	137,300
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	23,076	16,964
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	20,837	$ 21,260
Long Term Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, excluding options	$ 79,000

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Income taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 1,254,000	$ 0
Effective income tax rate	0.90%

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Legal matters (Details) - Patent Infringement $ in Millions		1 Months Ended
	Apr. 08, 2022 USD ($)	Jan. 22, 2021 petition
Commitments and Contingencies Disclosure [Abstract]
Number of petitions filed		2
Subsequent Event [Line Items]
Number of petitions filed		2
Subsequent Event [Member]
Subsequent Event [Line Items]
Awarded damages for past infringement | $	$ 41.8