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 September 30, 2022

☐	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 001-32587

ALTIMMUNE, INC.

(Exact Name of Registrant as Specified in its Charter)


Delaware		20-2726770
(State or Other Jurisdiction of Incorporation or Organization)		(I.R.S. Employer Identification No.)

910 Clopper Road Suite 201S, Gaithersburg, Maryland		20878
(Address of Principal Executive Offices)		(Zip Code)

(240) 654-1450

(Registrant’s Telephone Number, Including Area Code)

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 $0.0001 per share	ALT	The NASDAQ Global Market

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 (§ 232.405 of this chapter) 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 Act). Yes ☐ No ⌧

As of November 4, 2022, there were 49,159,056 shares of the registrant’s common stock, par value $0.0001 per share, outstanding.

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PART I. FINANCIAL INFORMATION

Item 1. Financial Statements

ALTIMMUNE, INC.

CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share data)


	September 30,		December 31,
	2022		2021
	(Unaudited)
ASSETS
Current assets:
Cash and cash equivalents	$	127,465	$	190,301
Restricted cash		34		34
Total cash, cash equivalents and restricted cash		127,499		190,335
Short-term investments		74,362		—
Accounts receivable		633		429
Income tax and R&D incentive receivables		3,720		5,410
Prepaid expenses and other current assets		4,790		7,952
Total current assets		211,004		204,126
Property and equipment, net		1,172		1,448
Intangible assets, net		12,419		12,419
Other assets		682		872
Total assets	$	225,277	$	218,865
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable	$	1,419	$	2,034
Contingent consideration		—		6,090
Accrued expenses and other current liabilities		14,323		10,152
Total current liabilities		15,742		18,276
Other long-term liabilities		4,506		1,454
Total liabilities		20,248		19,730
Commitments and contingencies (Note 14)
Stockholders’ equity:
Common stock, $0.0001 par value; 200,000,000 shares authorized; 49,161,637 and 40,993,768 shares issued and outstanding as of September 30, 2022 and December 31, 2021, respectively		5		4
Additional paid-in capital		566,551		497,342
Accumulated deficit		(356,224)		(293,171)
Accumulated other comprehensive loss, net		(5,303)		(5,040)
Total stockholders’ equity		205,029		199,135
Total liabilities and stockholders’ equity	$	225,277	$	218,865

The accompanying notes are an integral part of the unaudited consolidated financial statements.

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ALTIMMUNE, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(Unaudited)

(In thousands, except share and per share data)


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2022		2021		2022		2021
Revenues	$	2	$	158	$	42	$	1,133
Operating expenses:
Research and development		20,262		29,206		51,359		54,356
General and administrative		4,492		4,156		13,329		11,636
Impairment loss on construction-in-progress		—		—		—		8,070
Total operating expenses		24,754		33,362		64,688		74,062
Loss from operations		(24,752)		(33,204)		(64,646)		(72,929)
Other income (expense):
Interest expense		(64)		(33)		(191)		(67)
Interest income		1,053		13		1,402		88
Other income (expense), net		50		(286)		185		(293)
Total other income (expense), net		1,039		(306)		1,396		(272)
Net loss before income taxes		(23,713)		(33,510)		(63,250)		(73,201)
Income tax benefit		197		—		197		—
Net loss		(23,516)		(33,510)		(63,053)		(73,201)
Other comprehensive income — unrealized (loss) gain on short-term investments		(143)		(2)		(263)		4
Comprehensive loss	$	(23,659)	$	(33,512)	$	(63,316)	$	(73,197)
Net loss per share, basic and diluted	$	(0.48)	$	(0.81)	$	(1.37)	$	(1.79)
Weighted-average common shares outstanding, basic and diluted		49,286,535		41,370,768		45,881,547		40,843,905

The accompanying notes are an integral part of the unaudited consolidated financial statements.

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ALTIMMUNE, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(Unaudited)

(In thousands, except share amounts)


								Accumulated
				Additional				Other		Total
	Common Stock			Paid-In		Accumulated		Comprehensive		Stockholders’
	Shares	Amount		Capital		Deficit		Loss		Equity
Balance at December 31, 2021	40,993,768	$	4	$	497,342	$	(293,171)	$	(5,040)	$	199,135
Stock-based compensation	—		—		2,033		—		—		2,033
Exercise of stock options	95,771		—		197		—		—		197
Vesting of restricted stock awards including withholding, net	17,568		—		(170)		—		—		(170)
Issuance of common stock from Employee Stock Purchase Plan	16,450		—		113		—		—		113
Issuance of common stock in at-the-market offerings, net	335,485		—		2,990		—		—		2,990
Issuance of common stock upon exercise of warrants	1,760,854		—		—		—		—		—
Net loss	—		—		—		(19,430)		—		(19,430)
Balance at March 31, 2022	43,219,896	$	4	$	502,505	$	(312,601)	$	(5,040)	$	184,868
Stock-based compensation	—	$	—	$	2,048	$	—	$	—	$	2,048
Exercise of stock options	152,913		—		403		—		—		403
Vesting of restricted stock awards including withholding, net	(5,865)		—		(80)		—		—		(80)
Issuance of common stock in at-the-market offerings, net	2,157,717		1		21,346		—		—		21,347
Issuance of common stock related to contingent consideration liability	847,444		—		6,176		—		—		6,176
Unrealized (loss) gain on short-term investments	—		—		—		—		(120)		(120)
Net loss	—		—		—		(20,107)		—		(20,107)
Balance at June 30, 2022	46,372,105	$	5	$	532,398	$	(332,708)	$	(5,160)	$	194,535
Stock-based compensation	—	$	—	$	2,128	$	—	$	—	$	2,128
Exercise of stock options	76,161		—		268		—		—		268
Vesting of restricted stock awards including withholding, net	(7,744)		—		(140)		—		—		(140)
Issuance of common stock in at-the-market offerings, net	2,711,013		—		31,829		—		—		31,829
Issuance of common stock from Employee Stock Purchase Plan	9,945		—		68		—		—		68
Other increase	157		—		—		—		—		—
Unrealized loss on short-term investments	—		—		—		—		(143)		(143)
Net loss	—		—		—		(23,516)		—		(23,516)
Balance at September 30, 2022	49,161,637	$	5	$	566,551	$	(356,224)	$	(5,303)	$	205,029

The accompanying notes are an integral part of the unaudited consolidated financial statements.

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ALTIMMUNE, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(Unaudited)

(In thousands, except share amounts)


								Accumulated
				Additional				Other		Total
	Common Stock			Paid-In		Accumulated		Comprehensive		Stockholders’
	Shares	Amount		Capital		Deficit		Loss		Equity
Balance at December 31, 2020	37,142,946	$	4	$	417,337	$	(186,421)	$	(5,044)	$	225,876
Stock-based compensation	—		—		1,218		—		—		1,218
Vesting of restricted stock awards including withholding, net	(6,349)		—		(92)		—		—		(92)
Issuance of common stock from Employee Stock Purchase Plan	8,733		—		106		—		—		106
Retirement of common stock in exchange for common stock warrant	(1,000,000)		—		(7,540)		(9,660)		—		(17,200)
Issuance of common stock warrant in exchange for retirement of common stock	—		—		17,200		—		—		17,200
Issuance of common stock in at-the-market offerings, net	2,110,800		—		34,178		—		—		34,178
Issuance of common stock upon cashless exercise of warrants	1,050		—		10		—		—		10
Unrealized gain on short-term investments	—		—		—		—		5		5
Net loss	—		—		—		(14,864)		—		(14,864)
Balance at March 31, 2021	38,257,180	$	4	$	462,417	$	(210,945)	$	(5,039)	$	246,437
Stock-based compensation	—	$	—	$	1,485	$	—	$	—	$	1,485
Exercise of stock options	38,217		—		94		—		—		94
Vesting of restricted stock awards including withholding, net	(7,583)		—		(90)		—		—		(90)
Issuance of common stock in at-the-market offerings, net	1,405,710		—		18,178		—		—		18,178
Unrealized (loss) gain on short-term investments	—		—		—		—		1		1
Net loss	—		—		—		(24,827)		—		(24,827)
Balance at June 30, 2021	39,693,524	$	4	$	482,084	$	(235,772)	$	(5,038)	$	241,278
Stock-based compensation	—	$	—	$	1,497	$	—	$	—	$	1,497
Exercise of stock options	398		—		6		—		—		6
Vesting of restricted stock awards including withholding, net	(6,521)		—		(124)		—		—		(124)
Issuance of common stock from Employee Stock Purchase Plan	15,367		—		119		—		—		119
Unrealized loss on short-term investments	—		—		—		—		(2)		(2)
Net loss	—		—		—		(33,510)		—		(33,510)
Balance at September 30, 2021	39,702,768	$	4	$	483,582	$	(269,282)	$	(5,040)	$	209,264

The accompanying notes are an integral part of the unaudited consolidated financial statements.

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ALTIMMUNE, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

(In thousands)


	Nine Months Ended September 30,
	2022		2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$	(63,053)	$	(73,201)
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of contingent consideration liability		86		1,560
Impairment loss on construction-in-progress		—		8,070
Stock-based compensation expense		6,209		4,200
Depreciation and amortization		31		434
Unrealized (gains) losses on foreign currency exchange		(183)		297
Changes in operating assets and liabilities:
Accounts receivable		(204)		3,036
Prepaid expenses and other assets		3,204		(5,263)
Accounts payable		(615)		(606)
Accrued expenses and other liabilities		7,555		6,916
Income tax and R&D incentive receivables		1,690		(1,714)
Net cash used in operating activities		(45,280)		(56,271)
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sales and maturities of short-term investments		—		82,406
Purchases of short-term investments		(74,292)		(7,592)
Purchases of property and equipment, net		(88)		(11,970)
Cash paid for internally developed patents		—		(190)
Net cash (used in) provided by investing activities		(74,380)		62,654
CASH FLOWS FROM FINANCING ACTIVITIES:
Payments of deferred offering costs		—		(118)
Proceeds from issuance of common stock in at-the-market offerings, net		56,166		52,356
Proceeds from issuance of common stock from Employee Stock Purchase Plan		181		225
Proceeds from exercises of stock options, net		477		100
Net cash provided by financing activities		56,824		52,563
Net (decrease) increase in cash and cash equivalents and restricted cash		(62,836)		58,946
Cash, cash equivalents and restricted cash at beginning of period		190,335		115,952
Cash, cash equivalents and restricted cash at end of period	$	127,499	$	174,898

SUPPLEMENTAL NON-CASH ACTIVITIES:
Common stock issued related to contingent consideration liability	$	6,176	$	—
Operating lease liability and right of use asset addition	$	—	$	72

The accompanying notes are an integral part of the unaudited consolidated financial statements.

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ALTIMMUNE, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

1. Nature of Business and Basis of Presentation

Nature of Business

Altimmune, Inc., headquartered in Gaithersburg, Maryland, United States, together with its subsidiaries (collectively, the “Company” or “Altimmune”) is a clinical stage biopharmaceutical company incorporated under the laws of the State of Delaware.

The Company is focused on developing treatments for obesity and liver diseases. The Company’s pipeline includes next generation peptide therapeutics for obesity and non-alcoholic steatohepatitis (“NASH”) (for both, pemvidutide, formerly known as ALT-801), and for chronic hepatitis B (HepTcell). Since its inception, the Company has devoted substantially all of its efforts to business planning, research and development, recruiting management and technical staff and raising capital, and has financed its operations through the issuance of common and preferred stock, long-term debt and proceeds from research grants and government contracts. The Company has not generated any revenues from the sale of any products to date, and there is no assurance of any future revenues from product sales.

Basis of Presentation

The accompanying unaudited consolidated financial statements are prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Accordingly, they do not include all of the information and disclosures required by accounting principles generally accepted in the United States (“U.S. GAAP”) for complete consolidated financial statements and should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2021 included in the Annual Report on Form 10-K which was filed with the SEC on March 15, 2022. In the opinion of management, the Company has prepared the accompanying unaudited consolidated financial statements on the same basis as the audited consolidated financial statements, and these consolidated financial statements include all adjustments, consisting only of normal recurring adjustments, necessary for a fair presentation of the results of the interim periods presented. The operating results for the interim periods presented are not necessarily indicative of the results expected for the full year 2022 or any future years or periods.

The accompanying unaudited consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.

The accompanying unaudited consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets, and the satisfaction of liabilities in the ordinary course of business. The financial statements do not include any adjustments relating to the recoverability and classification of recorded assets and liabilities that might be necessary should we be unable to continue as a going concern.

2. Summary of Significant Accounting Policies

During the nine months ended September 30, 2022, there have been no significant changes to the Company’s summary of significant accounting policies contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 as filed with the SEC.

Use of Estimates

The preparation of these financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The extent to which the COVID-19 pandemic, including any resurgences or the emergence of new variants, may directly or indirectly impact the Company’s business, financial condition, and results of operations is highly uncertain and subject to change.

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The Company considered the potential impact of the COVID-19 pandemic on the Company’s estimates and assumptions and determined that there was not a material impact to the Company’s unaudited consolidated financial statements as of and for the three and nine months ended September 30, 2022. However, actual results could differ from those estimates and there may be changes to the Company’s estimates in future periods.

3. Fair Value Measurements

The Company’s assets measured at fair value on a recurring basis as of September 30, 2022 consisted of the following (in thousands):


	Fair Value Measurement at September 30, 2022
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents - money market funds	$	123,921	$	123,921	$	—	$	—
Short-term investments		74,362		—		74,362		—
Total	$	198,283	$	123,921	$	74,362	$	—

The Company’s assets and liabilities measured at fair value on a recurring basis as of December 31, 2021 consisted of the following (in thousands):


	Fair Value Measurement at December 31, 2021
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents - money market funds	$	65,634	$	65,634	$	—	$	—
Total	$	65,634	$	65,634	$	—	$	—
Liabilities:
Contingent consideration liability (see Note 6)	$	6,090	$	—	$	—	$	6,090
Total	$	6,090	$	—	$	—	$	6,090

As described in Note 6 the remaining milestone payment underlying the contingent consideration liability was fully settled in shares of the Company’s common stock. As of September 30, 2022, the Company had no contingent consideration liability.

Short-term investments have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, utilizing third party pricing services or other market observable data (Level 2). The pricing services utilize industry standard valuation models, including both income and market-based approaches and observable market inputs to determine value.

Short-term investments had quoted prices as of September 30, 2022 as shown below (in thousands):


	September 30, 2022
	Amortized Cost		Unrealized Loss		Market Value
United States treasury securities	$	17,784	$	(112)	$	17,672
Commercial paper and corporate debt securities		49,931		(124)		49,807
Asset backed securities		6,910		(27)		6,883
Total	$	74,625	$	(263)	$	74,362

Separate disclosure is required for assets and liabilities measured at fair value on a recurring basis from those measured at fair value on a non-recurring basis. Assets recorded at fair value on a non-recurring basis, such as property and equipment and intangible assets are recognized at fair value when they are impaired. During the nine months ended September 30, 2022, the Company had no significant assets or liabilities that were measured at fair value on a non-recurring basis. During the year ended December 31, 2021, the Company recorded non-cash impairment charges to property and equipment, net on a non-recurring basis (see below).

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Lonza Manufacturing Agreement

In March 2021, the Company expanded its manufacturing collaboration with Lonza Houston, Inc. (“Lonza”) for the manufacture of AdCOVID or other adenovirus-based vaccines. Under the expanded agreement, the Company had committed approximately $23.0 million to Lonza to procure long-lead equipment and construct a dedicated manufacturing suite for clinical and commercial production of adenovirus-based vaccines. In June 2021, the Company announced the discontinuation of further development of AdCOVID following the Company’s review of findings from its Phase 1 clinical trial. Construction continued at Lonza, and the Company assessed its strategic options with respect to the suite. This work was completed during the fourth quarter of 2021. The Company capitalized a total of $11.4 million as construction-in-progress (“CIP”) during the nine months ended September 30, 2021 under this expanded agreement.

In connection with the discontinuation of further development of AdCOVID, the Company recorded a non-cash impairment charge of $8.1 million in the unaudited consolidated statements of operations and comprehensive loss for the nine months ended September 30, 2021 to write-down the CIP associated with the construction of the Lonza facility to its fair value of $3.3 million as of September 30, 2021. As of September 30, 2021, the fair value of the CIP related assets was primarily determined utilizing the cost approach, which reflected the replacement cost of the asset being appraised, adjusted for contractual restrictions on the assets, the probability of satisfying the contractual restrictions, physical deterioration, functional obsolescence and economic obsolescence. The fair value measurement was considered a Level 3 measurement within the valuation hierarchy.

Furthermore, the remaining $3.3 million CIP was fully charged to impairment during the three months ended December 31, 2021 upon termination of the agreement.

4. Operating Leases

The Company rents office and laboratory space in the United States which expires in April 2025. Rent expense under the Company’s operating leases was $0.1 million and $0.4 million during each of the three and nine months ended September 30, 2022 and 2021, respectively. Rent expense includes short-term leases and variable lease costs that are not included in the lease obligation.

Short-term leases are leases having a term of twelve months or less. The Company recognizes short-term leases on a straight-line basis and does not record a related lease asset or liability for such leases.

The office space lease provides for increases in future minimum annual rental payments as defined in the lease agreement. The office space lease also includes an option to renew the lease as of the end of the term. The Company has determined that the lease renewal option is not reasonably certain of being exercised.

The cash paid for operating lease liabilities for each of the nine months ended September 30, 2022 and 2021 was $0.4 million.

Supplemental other information related to the operating leases balance sheet information is as follows (in thousands):



	September 30, 2022			December 31, 2021
Operating lease obligations (see Note 5 and 7)	$	1,230		$	1,535
Operating lease right-of-use assets (included in "Other assets" in Balance Sheet)	$	649		$	798
Weighted-average remaining lease term (years)		2.6			3.3
Weighted-average discount rate		7.2	%		7.2	%

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5. Accrued Expenses

Accrued expenses and other current liabilities consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Accrued professional services	$	624	$	396
Accrued payroll and employee benefits		2,110		2,313
Accrued research and development		9,930		6,988
Lease obligation, current portion (see Note 4)		442		411
Income tax payable		1,169		—
Accrued interest and other		48		44
Total accrued expenses and other current liabilities	$	14,323	$	10,152

6. Contingent Consideration

The Company entered into an Agreement and Plan of Merger and Reorganization, dated July 8, 2019, by and among the Company, Springfield Merger Sub, Inc., Springfield Merger Sub, LLC, Spitfire Pharma, Inc. and David Collier, as the Stockholder Representative (the “Spitfire Merger Agreement”) to acquire all of the equity interests of Spitfire Pharma, Inc. (“Spitfire”). Spitfire was a privately held, preclinical pharmaceutical company developing a novel GLP-1/glucagon receptor dual agonist for the treatment of NASH.

The transaction closed on July 12, 2019. The Company issued 1,887,250 unregistered shares of its common stock as upfront consideration to certain former securityholders of Spitfire, representing an amount equal to $5.0 million less working capital and transaction expense adjustment amounts as defined in the agreement.

The acquisition of Spitfire was accounted for as an asset acquisition instead of a business combination because substantially all of the fair value of the gross assets acquired was concentrated in a single identifiable asset or group of similar identifiable assets, and therefore, the asset was not considered a business. The Company expensed the acquired intellectual property as of the acquisition date as in-process research and development with no alternative future uses.

The Spitfire Merger Agreement also includes future contingent payments up to $88.0 million in cash and shares of the Company’s common stock as follows:

●

a one-time payment of $5.0 million (the “IND Milestone Consideration Amount”) within sixty days of the submission of an Investigational New Drug Application (“IND”) to the United States Food and Drug Administration (the “FDA”) or other applicable governmental authority in a foreign jurisdiction, which IND has not been rejected or placed on clinical hold by the FDA or such applicable foreign governmental authority within time specified in the Spitfire Merger Agreement;

●

a one-time payment of $3.0 million (the “Phase 2 Milestone Consideration Amount” and together with the IND Milestone Consideration Amount, the “Regulatory Milestones”) within sixty days of the initiation (first patient, first dosing) of a Phase 2 clinical trial of a product candidate anywhere in the world (a “Phase 2 Milestone Event”); and

●

payments of up to $80.0 million upon the achievement of specified worldwide net sales (the “Sales Milestones”) of all products developed using the technology acquired in the Amended and Restated License Agreement, dated July 12, 2019, by and between Mederis Diabetes, LLC and Spitfire, within ten years following the approval of a new drug application filed with the FDA.

The Regulatory Milestones were payable in shares of the Company’s common stock, with the number of shares of the Company’s common stock issued in connection with each milestone amount, if any, dependent on the share price at the time of achievement. The number of shares issued in consideration for the IND Milestone Consideration Amount was determined based on the lower of (A) the average of the closing prices of the Company’s common stock as reported on the Nasdaq Global Market for the twenty (20) consecutive trading days prior to the IND Reference Date or (B) $2.95.

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The number of shares issued in consideration for the Phase 2 Milestone Consideration Amount was determined based on the lower of (A) the average of the closing trading prices of the Company’s common stock as reported on the Nasdaq Global Market for the twenty (20) consecutive trading days immediately preceding the date of the occurrence of the Phase 2 Milestone Event or (B) $3.54.

The contingent payments related to the Regulatory Milestones were stock-based payments accounted for under FASB Accounting Standards Codification Topic 480, Distinguishing Liabilities From Equity (“ASC 480”). Such stock-based payments are subject to a lock-up whereby 50% of the shares are released at 3 months following issuance and 50% are released at 6 months following issuance. The future contingent payments related to the Sales Milestones are predominately cash-based payments accounted for under FASB Accounting Standards Codification Topic 450, Contingencies. Accordingly, the Company will recognize the Sales Milestones when the contingency is probable and the amount can be reasonably estimated.

On November 3, 2020, the Company received acknowledgement from the Australian Government Department of Health on the Company’s submitted clinical trial notification (“CTN”) which triggered the obligation to settle the IND Milestone payment to the former owners. As a result, on November 19, 2020, the Company issued 1,694,906 shares of its common stock valued at $9.57 per share for the amount value of $13.6 million to the former Spitfire stockholders. Pursuant to the Spitfire Merger Agreement, the Company issued the shares within sixty days of the submission of the CTN, which was October 29, 2020. From September 30, 2020 through November 19, 2020, the date of issuance, the Company recognized a decrease in the fair value of the IND Milestone payment of $5.4 million to research and development expense and reclassified the balance in the contingent consideration liability associated with the fair value of the IND Milestone payment to equity in the Company’s consolidated balance sheet.

On April 26, 2022, the Company dosed the first patient in the Phase 2 MOMENTUM trial of pemvidutide in obesity, which triggered the obligation to pay the Phase 2 Milestone Consideration Amount to the former owners. As a result, on June 10, 2022, the Company issued 847,444 shares of its common stock valued at $8.55 per share for the amount value of $7.2 million to the former Spitfire stockholders. From the last valuation date on March 31, 2022 through June 10, 2022, the date of issuance, the Company recognized an increase in the fair value of the Phase 2 Milestone Consideration Amount of $1.9 million to research and development expense and reclassified the balance in the contingent consideration liability to equity in the Company’s consolidated balance sheet. As of September 30, 2022, the Company had no contingent consideration liability.

Below is a summary of the contingent consideration activity (in thousands):


	Nine Months Ended September 30,
	2022		2021
Beginning balance	$	6,090	$	5,390
Change in fair value		86		1,560
Fair value of payments settled in common stock (Phase II Milestone)		(6,176)		—
Ending balance	$	—	$	6,950

7. Other Long-Term Liabilities

During the nine months ended September 30, 2022, the Company received a total of $3.4 million in cash for research and development (“R&D”) incentive credit that the Company earned during the fiscal years 2021 and 2020 through the participation in the Australian research and development incentive credit program administered through the Australian Tax Office. The Company recorded the receipt as long-term liability until there is reasonable assurance that the Company will comply with the conditions attached to the incentive credit. See Note 2. Summary of Significant Accounting Policies in the Company’s 2021 Annual Report on Form 10-K for accounting policies related to research and development incentive credits.

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The Company’s other long-term liabilities are summarized as follows (in thousands):



	September 30, 2022		December 31, 2021
Research and development incentive credit	$	3,402	$	—
Lease obligation, long-term portion (see Note 4)		788		1,124
Conditional economic incentive grants		250		250
Other		66		80
Total other long-term liabilities	$	4,506	$	1,454

8. Common Stock

Public Offering

On July 16, 2020, the Company offered and sold (i) 3,369,564 shares of common stock, at a price to the public of $23.00 per share, and (ii) pre-funded warrants of the Company to purchase 1,630,436 shares of common stock at an exercise price equal to $0.0001 per share (the “Pre-Funded Warrants”), at a price to the public of $22.9999 per share of common stock underlying the Pre-Funded Warrants (equal to the public offering price per share of Common Stock, minus the exercise price of each Pre-Funded Warrant). The Pre-Funded Warrants are exercisable at any time, provided that each Pre-Funded Warrant holder will be prohibited from exercising such Pre-Funded Warrants into shares of the Company’s common stock if, as a result of such exercise, the holder, together with its affiliates, would own more than 4.99% of the total number of shares of the Company’s common stock then issued and outstanding, which percentage may change at the holders’ election to any other number less than or equal to 19.99% upon 61 days’ notice to the Company. The gross proceeds of this offering were approximately $132.2 million, which includes the exercise in full of the underwriters’ option to purchase an additional 750,000 shares of common stock, before deducting underwriting discounts and commissions and offering expenses during the third quarter of 2020. The net proceeds of this offering were approximately $124.0 million, after deducting underwriting discounts and commissions and offering expenses payable by the Company.

The Company has assessed the Pre-Funded Warrants for appropriate equity or liability classification and determined that the Pre-Funded Warrants are freestanding instruments that do not meet the definition of a liability pursuant to ASC 480 and do not meet the definition of a derivative pursuant to FASB Accounting Standards Codification Topic 815, Derivatives and Hedging (“ASC 815”). The Pre-Funded Warrants are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815. Accordingly, the Pre-Funded Warrants are classified as equity and are accounted for as a component of additional paid-in capital at the time of issuance. As of September 30, 2022, 760,870 of the Pre-Funded Warrants were exercised, leaving 869,566 remaining Pre-Funded Warrants unexercised.

At-the-Market Offerings

On February 25, 2021, the Company entered into an Equity Distribution Agreement (the “2021 Agreement”) with Piper Sandler & Co., Evercore Group L.L.C. and B. Riley Securities, Inc., serving as sales agents (the “Sales Agents”) with respect to an at-the-market offerings program under which the Company offered and sold shares of its common stock, par value $0.0001 per share (the “Common Stock”), having an aggregate offering price of up to $125.0 million (the “Shares”) through the Sales Agents (the “2021 Offering”). All the Shares offered and sold in the 2021 Offering were issued pursuant to the Company’s Registration Statement on Form S-3 filed with the Securities and Exchange Commission (the “SEC”) on December 31, 2020, which was declared effective on January 11, 2021 (“2021 Shelf”), the prospectus supplement relating to the 2021 Offering filed with the SEC on February 25, 2021 and any applicable additional prospectus supplements related to the 2021 Offering that form a part of the Registration Statement.

During the nine months ended September 30, 2022, the Company sold 5,204,415 shares of Common Stock under the 2021 Agreement resulting in approximately $56.2 million in proceeds, net of $1.9 million commission and other offering costs. As of September 30, 2022, the Company has sold 10,004,869 shares of Common Stock under the 2021 Agreement resulting in approximately $121.0 million in proceeds, net of $4.0 million commission and other offering costs, As of September 30, 2022, there were no remaining shares available for issuance under the 2021 Agreement. The Company

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recorded approximately $0.3 million of other offering costs which offset the proceeds received from the shares sold through September 30, 2022.

Exchange Agreement

On February 25, 2021, the Company entered into an exchange agreement (the “Exchange Agreement”) with an investor and its affiliates (the “Exchanging Stockholders”), pursuant to which the Company exchanged an aggregate of 1,000,000 shares of the Company’s common stock, par value $0.0001 per share, owned by the Exchanging Stockholders for pre-funded warrants (the “Exchange Warrants”) to purchase an aggregate of 1,000,000 shares of common stock (subject to adjustment in the event of any stock dividends and splits, reverse stock split, recapitalization, reorganization or similar transaction, as described in the Exchange Warrants), with an exercise price of $0.0001 per share. The Exchange Warrants did not have an expiration date and were exercisable at any time except that the Exchange Warrants could not be exercised by the Exchanging Stockholders if, after giving effect thereto, the Exchanging Stockholders would beneficially own more than 9.99% of the Company’s common stock, subject to certain exceptions. In accordance with FASB Accounting Standards Codification Topic 505, Equity, the Company recorded the retirement of the common stock exchanged as a reduction of common shares outstanding and a corresponding debit to additional paid-in-capital and accumulated deficit at the fair value of the Exchange Warrants on the issuance date. The Exchange Warrants were classified as equity in accordance with ASC 480 and the fair value of the Exchange Warrants was recorded as a credit to additional paid-in-capital and is not subject to remeasurement. The Company determined that the fair value of the Exchange Warrants is substantially similar to the fair value of the retired shares on the issuance date due to the negligible exercise price for the Exchange Warrants. On January 24, 2022, the Exchange Warrants to purchase 1,000,000 shares were net exercised, resulting in the issuance of 999,984 shares of common stock, and no Exchange Warrants remain outstanding.

9. Warrants

A summary of warrant activity during the nine months ended September 30, 2022 is as follows:


				Weighted-Average
			Weighted	Remaining
	Number of		Average	Contractual Term
	Warrants		Exercise Price	(Years)
Warrants outstanding, December 31, 2021	2,776,191
Expired	(155)
Exercises (see Note 8)	(1,760,870)
Warrants outstanding, September 30, 2022	1,015,166	$	0.66	1.2

The warrants outstanding as of September 30, 2022 included 869,566 Pre-Funded Warrants with an exercise price of $0.0001 per-share and no expiration date.

10. Stock-Based Compensation

Stock Options

The Company’s stock option awards generally vest over four years and typically have a contractual life of ten years. As of September 30, 2022, there was $13.7 million of unrecognized compensation cost related to stock options, which is expected to be recognized over a weighted-average period of 2.6 years. During the nine months ended September 30, 2022, the Company granted 1,433,427 stock options with a weighted average exercise price of $8.39 and per share weighted average grant date fair value of $6.97.

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Information related to stock options outstanding as of September 30, 2022 is as follows (in thousands, except share and per share data):


				Weighted-Average
		Weighted-		Remaining
	Number of	Average		Contractual Term	Aggregate Intrinsic
	Stock Options	Exercise Price		(Years)	Value
Outstanding	3,528,473	$	9.09	5.9	$	16,975
Exercisable	1,382,587	$	8.75	5.8	$	7,824
Unvested	2,145,886	$	9.31	6.0	$	9,151

Restricted Stock

As of September 30, 2022, the Company had unvested restricted stock of 13,454 shares with total unrecognized compensation expense of $47,000, which the Company expects to recognize over a weighted average period of approximately 0.2 years. During the nine months ended September 30, 2022, the Company issued 34,132 of unrestricted common stock as a result of the vesting of 60,546 restricted stock net of 26,414 shares of common stock withheld to satisfy tax withholding obligations.

Restricted Stock Units (RSUs)

During the nine months ended September 30, 2022, the Company granted 285,000 shares of RSUs with a weighted average grant date fair value of $7.11 which vest over four years. As of September 30, 2022, the Company had unvested RSUs of 470,275 shares with total unrecognized compensation expense of $3.4 million, which the Company expects to recognize over a weighted average period of approximately 3.1 years. During the nine months ended September 30, 2022, the Company issued 30,373 shares of unrestricted common stock as a result of the vesting of 46,653 RSUs net of 16,280 shares of common stock withheld to satisfy tax withholding obligations.

2019 Employee Stock Purchase Plan (ESPP)

Under the ESPP, employees purchased 26,395 shares for $0.2 million during the nine months ended September 30, 2022. During the three and nine months ended September 30, 2022, the Company recognized compensation expense of $0.1 million and $0.2 million respectively. During the three and nine months ended September 30, 2021, the Company recognized compensation expense of $29,000 and $0.3 million, respectively.

Stock-based Compensation Expense

Stock-based compensation expense is classified in the unaudited consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2022 and 2021 as follows (in thousands):


	For the Three Months Ended				For the Nine Months Ended
	September 30,				September 30,
	2022		2021		2022		2021
Research and development	$	743	$	449	$	2,024	$	1,211
General and administrative		1,385		1,048		4,185		2,989
Total	$	2,128	$	1,497	$	6,209	$	4,200

11. U.S. Government Contracts and Grants

In June 2020, the Company was awarded $4.7 million from the U.S. Army Medical Research & Development Command (“USAMRDC”) to fund its Phase 1/2 clinical trial of T-COVID. The competitive award was granted by USAMRDC in collaboration with the Medical Technology Enterprise Consortium (“MTEC”), a 501(c)(3) biomedical technology consortium working in partnership with the Department of Defense (“DoD”). Under the contract, MTEC paid the Company a firm fixed fee based upon the achievement of certain milestones for conduct and completion of a Phase 1/2 study and research and development work on the replication-deficient adenovirus 5 (“RD-Ad5”) vector vaccine

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platform. For the nine months ended September 30, 2021, the Company recognized approximately $0.5 million of grant revenue under the contract, which completed the full recognition of this award. No revenue was recognized for this contract for the three and nine months ended September 30, 2022.

In July 2016, the Company signed a five-year contract with Biomedical Advanced Research and Development Authority (“BARDA”). The contract, as amended, had a total value of up to $136.8 million to be used to fund clinical development of NasoShield. Under the contract, BARDA paid the Company a fixed fee and reimbursed certain costs for the research and development of an Ad5-vectored, protective antigen-based intranasal anthrax vaccine through cGMP manufacture and conduct of a Phase 1 clinical trial dose ranging assessment of safety and immunogenicity. The contract consisted of an initial base performance period providing approximately $30.9 million in funding for the period July 2016 through December 2021. BARDA had seven options to extend the contract to fund certain continued development and manufacturing activities for the anthrax vaccine, including Phase 2 clinical studies. Each option, if exercised by BARDA, would have provided additional funding ranging from approximately $1.1 million to $34.4 million for a three-year period beginning in 2021. For the three and nine months ended September 30, 2021, the Company recognized approximately $0.1 million and $0.4 million, respectively, of grant revenue under the BARDA contract. For the three and nine months ended September 30, 2022, the Company has recognized de minimis grant revenue related to the close-out of the BARDA contract. BARDA did not extend the contract beyond the end of December 2021.

12. Income Taxes

During the three and nine months ended September 30, 2022, the Company recorded a total of $0.2 million income tax benefit related to interest received and receivable on income tax refunds. Other than the tax benefit related to interest, the Company did not record an income tax benefit in the three and nine months ended September 30, 2022 and 2021 due to a full valuation allowance.

13. Net Loss Per Share

Because the Company has reported a net loss attributable to common stockholders for all periods presented, basic and diluted net loss per share attributable to common stockholders are the same for all periods presented.

Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted average numbers of shares of common stock outstanding for the period. Basic shares outstanding includes the weighted average effect of the Company’s outstanding pre-funded warrants, the exercise of which requires little or no consideration for the delivery of shares of common stock.

Diluted net loss per share is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period. As such, all unvested restricted stock, restricted stock units, common stock warrants and stock options have been excluded from the computation of diluted weighted average shares outstanding because such securities would have an anti-dilutive impact for all periods presented.

Potential common shares issuable upon conversion, vesting or exercise of unvested restricted stock, restricted stock units, common stock warrants and stock options that are excluded from the computation of diluted weighted-average shares outstanding, as they are anti-dilutive, are as follows:


	For the Three and Nine Months Ended
	September 30,
	2022	2021
Common stock warrants	145,600	145,755
Common stock options	3,542,534	2,626,482
Restricted stock units	470,275	207,529
Restricted stock	13,454	94,181

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14. Commitments and Contingencies

Spitfire Acquisition

As disclosed in Note 6, the Company is obligated to make payments of up to $80.0 million upon the achievement of specified worldwide net sales of all products developed using the technology acquired from Spitfire Pharma Inc. within ten years following the approval of a new drug application filed with the FDA.

Litigation

In December 2019, a complaint was filed by Dr. De-Chu Christopher Tang (“Plaintiff”) against the Company, which was removed to the United States District Court for the Eastern District of Texas. The Plaintiff amended the complaint in February 2020 to include Vipin K. Garg and David J. Drutz as defendants, in addition to the Company (Dr. Garg, Dr. Drutz, and the Company are collectively referred to as “Defendants”). In March 2020 the Defendants filed a motion to dismiss the complaint. The Court denied the motion without prejudice and allowed Plaintiff an opportunity to file an amended complaint. Plaintiff’s second amended complaint was filed on April 17, 2020, and Defendants filed a motion to dismiss that complaint on May 1, 2020. A hearing on Defendants’ motion to dismiss was held on May 20, 2020. Plaintiff, who is representing himself, alleges five causes of action as follows: (1) Defendants’ alleged retention of Plaintiff’s lab notebooks after the termination of his employment in 2012; (2) alleged plagiarism based on publishing an article without naming Plaintiff as an author; (3) use of the Adhigh System, which Plaintiff alleges he developed; (4) allegations that Defendants manipulated the Company’s stock and caused a decrease in value; and (5) allegations that the Defendants “wast[ed] government grant money and poison[ed] science by leaving data to rot.” On September 30, 2020, Plaintiff filed a motion titled “Motion to Proscribe Defendants’ Allegedly Illegal Use of Plaintiff’s AdHigh System in Altimmune’s Human Clinical Trials,” to which Defendants filed an opposition on October 13, 2020. The court has not yet ruled on that motion, which also remains pending. On November 6, 2020, Defendants filed a motion for summary judgment on the basis of lack of personal jurisdiction, insufficient service of process, and failure to state a claim. The court ruled on that motion on March 25, 2021, which dismissed the case on the basis of lack of personal jurisdiction. On December 1, 2020, the magistrate judge assigned to the case issued a report and recommendation that Defendants’ motion to dismiss of May 1, 2020 be granted and that this action be dismissed for lack of personal jurisdiction. Plaintiff filed objections to the report and recommendation on December 14, 2020, and the resolution of those objections by the district court remains pending.

In December 2021, the Plaintiff refiled the complaint in the United States District Court for the District of Maryland. On February 24, 2022, Defendants filed a memorandum containing a brief description of the planned motion and a concise summary of the factual and legal support for it. On the basis of that memorandum, the Court granted Defendants’ request to file a motion to dismiss and allowed Plaintiff an opportunity to file an amended complaint. Plaintiff’s amended complaint was filed on March 3, 2022, and Defendants filed a motion to dismiss that complaint on April 4, 2022. The Company believes the allegations in the complaint are without merit and intends to vigorously defend the litigation.

The Company is a party in various contracts and subject to disputes, litigation and potential claims arising in the ordinary course of business, none of which are currently reasonably possible or probable of material loss.

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

The following discussion and analysis of our financial condition and results of operations should be read together with our consolidated financial statements and related notes appearing elsewhere in this Quarterly Report on Form 10-Q and our consolidated financial statements and related notes for the year ended December 31, 2021 included in our Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission on March 15, 2022.

This Quarterly Report on Form 10-Q contains forward-looking statements that involve substantial risks and uncertainties. The words “expect,” “anticipate,” “intend,” “plan,” “believe,” “estimate,” “may,” “will,” “should,” “could,” “target,” “strategy,” “intend,” “project,” “guidance,” “likely,” “usually,” “potential,” or the negative of these words or variations of such words, similar expressions, or comparable terminology are intended to identify such forward-looking statements, although not all forward-looking statements contain these identifying words. There are a number of important risks and uncertainties that could cause our actual results to differ materially from those indicated by forward-looking statements. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. A further list and description of risks, uncertainties and other factors that could cause actual results or events to differ materially from the forward-looking statements that we make is included in the cautionary statements herein and in our other filings with the Securities and Exchange Commission, including those set forth under Part I, Item 1A, Risk Factors in our Annual Report on Form 10-K for the year ended December 31, 2021. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments that we may make.

We have based the forward-looking statements included in this Quarterly Report on Form 10-Q on information available to us on the date of this quarterly report, and we assume no obligation to update any such forward-looking statements, other than as required by law. Although we undertake no obligation to revise or update any forward-looking statements, whether as a result of new information, future events or otherwise, you are advised to consult any additional disclosures that we may make directly to you or through reports that we, in the future, may file with the SEC, including Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K.

Overview

Altimmune, Inc. is a clinical stage biopharmaceutical company focused on developing treatments for obesity and liver diseases. Our lead product candidate, pemvidutide (formerly known as ALT-801), is a GLP-1/glucagon receptor dual agonist that is being developed for the treatment of obesity and non-alcoholic steatohepatitis (“NASH”). In addition, we are developing HepTcell, an immunotherapeutic agent designed to achieve a functional cure for chronic hepatitis B.

Impact of COVID-19

We are closely monitoring how the spread of COVID-19, including any resurgences or the emergence of new variants, is affecting our employees, business, preclinical studies and clinical trials. We have reopened our executive office to allow employees to return to the office based on an approach that is intended to comply with federal and state guidelines, with a focus on employee safety and optimal work environment. We are continuing our regular interactions with the FDA and other regulatory agencies and, based on current information, we do not anticipate COVID-19 to materially affect our regulatory timelines for our ongoing clinical trials. Furthermore, as a government contractor, we are subject to the federal government vaccination mandate, which requires federal contractor employees, except in certain limited circumstances, to be vaccinated against COVID-19 by December 8, 2021. While the vaccination mandate remains subject to the interpretation of various government agencies and other entities, and questions remain regarding the specific application of the vaccination mandate, we are continuing to develop and implement health, safety, employment and operational protocols in order to timely comply with the vaccination mandate. As of and for the nine months ended September 30, 2022, the vaccination mandate has not had a material impact on our employees or operations.

Although operations have not been materially affected by the COVID-19 pandemic as of and for the three and nine months ended September 30, 2022, at this time, however, disruptions caused by the COVID-19 pandemic may result in difficulties or delays in initiating, enrolling, conducting or completing our planned and ongoing trials and the incurrence

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of unforeseen costs as a result of disruptions in clinical supply or preclinical study or clinical trial delays. The impact of COVID-19 on our future results will largely depend on future developments, which are highly uncertain and cannot be predicted with confidence, such as the ultimate geographic spread of the disease, the duration of the pandemic, travel restrictions and social distancing in the United States and other countries, business closures or business disruptions, the ultimate impact on financial markets and the global economy, and the effectiveness of actions taken in the United States and other countries to contain and treat the disease. In addition, a recurrence of COVID-19 cases, or variants thereof, could cause other widespread or more severe impacts depending on where infection rates are highest. We continue to monitor developments as we deal with the disruptions and uncertainties relating to the COVID-19 pandemic. See “Risk Factors” in Part II, Item 1A of this Quarterly Report on Form 10-Q and “Item 1A. Risk Factors” of our Annual Report on Form 10-K for the year ended December 31, 2021.

Recent Global Events

Russia and Ukraine Conflict

The military conflict in Russia and Ukraine that began in February 2022 continues as of the date of this quarterly report. As the conflict continues to evolve, we are closely monitoring the impact on our business. The conflict, and the sanctions and counter-sanctions imposed in response to it, have created increased economic uncertainty and operational complexity globally. While we have no direct exposure to Russia and Ukraine, and do not at the moment believe the situation will have a material impact on our operating results, we are monitoring any broader economic impact from the situation. Should the conflict continue or escalate, it could have a significant negative effect on the global economy or on our operations, including continued inflationary pressures on raw materials, supply chain and logistics disruptions, volatility in foreign exchange rates and interest rates and heightened cybersecurity threats.

U.S. Government Contracts and Grants

In June 2020, we were awarded $4.7 million from the U.S. Army Medical Research & Development Command (“USAMRDC”) to fund our Phase 1/2 clinical trial of T-COVID. The competitive award was granted by USAMRDC in collaboration with the Medical Technology Enterprise Consortium (“MTEC”), a 501(c)(3) biomedical technology consortium working in partnership with the Department of Defense (“DoD”). Under the contract, MTEC paid us a firm fixed fee based upon the achievement of certain milestones for conduct and completion of a Phase 1/2 study and research and development work on the replication-deficient adenovirus 5 (“RD-Ad5”) vector vaccine platform. For the nine months ended September 30, 2021, we recognized approximately $0.5 million of grant revenue under the contract, which completed the full recognition of this award. No revenue was recognized for this contract for the three and nine months ended September 30, 2022.

In July 2016, we signed a five-year contract with Biomedical Advanced Research and Development Authority (“BARDA”). The contract, as amended, had a total value of up to $136.8 million to be used to fund clinical development of NasoShield. Under the contract, BARDA paid us a fixed fee and reimbursed certain costs for the research and development of an Ad5-vectored, protective antigen-based intranasal anthrax vaccine through cGMP manufacture and conduct of a Phase 1 clinical trial dose ranging assessment of safety and immunogenicity. The contract consisted of an initial base performance period providing approximately $30.9 million in funding for the period July 2016 through December 2021. BARDA had seven options to extend the contract to fund certain continued development and manufacturing activities for the anthrax vaccine, including Phase 2 clinical trials. Each option, if exercised by BARDA, would have provided additional funding ranging from approximately $1.1 million to $34.4 million for a three-year period beginning in 2021. For the three and nine months ended September 30, 2021, we recognized approximately $0.1 million and $0.4 million, respectively, of grant revenue under the BARDA contract. For the three and nine months ended September 30, 2022, we have recognized de minimis grant revenue related to the close-out of the BARDA contract. BARDA did not extend the contract beyond the end of December 2021.

Critical Accounting Policies and Significant Judgment and Estimates

Management’s Discussion and Analysis of Financial Condition and Results of Operations is based upon our unaudited consolidated financial statements, which have been prepared in accordance with accounting principles generally

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accepted in the U.S. and the rules and regulations of the SEC for interim financial reporting. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues, expenses and the disclosure of contingent liabilities in our consolidated financial statements. We base our estimates and judgments on historical experience, knowledge of current conditions and expectations of what could occur in the future given available information.

There have been no changes in our critical accounting policies and significant judgment and estimates as disclosed in our Annual Report on Form 10-K for the year ended December 31, 2021. For more information regarding our critical accounting policies, we encourage you to read the discussion contained in Item 7 under the heading “Critical Accounting Policies and Significant Judgments and Estimates” and Note 2 “Summary of Significant Accounting Policies” included in the notes to the consolidated financial statements contained in our Annual Report on Form 10-K for the year ended December 31, 2021.

Results of Operations

Comparison of the three months ended September 30, 2022 and 2021:


	For the Three Months Ended
	September 30,
(in thousands)	2022		2021		Increase (Decrease)
Revenue	$	2	$	158	$	(156)	(99)	%
Operating expenses:
Research and development		20,262		29,206		(8,944)	(31)	%
General and administrative		4,492		4,156		336	8	%
Total operating expenses		24,754		33,362		(8,608)	(26)	%
Loss from operations		(24,752)		(33,204)		8,452	25	%
Other income (expense):
Interest expense		(64)		(33)		(31)	(94)	%
Interest income		1,053		13		1,040	8,000	%
Other income (expense), net		50		(286)		336	(117)	%
Total other income (expense), net		1,039		(306)		1,345	(440)	%
Net loss before income taxes		(23,713)		(33,510)		9,797	29	%
Income tax benefit		197		—		197
Net loss	$	(23,516)	$	(33,510)	$	9,994	30	%

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Comparison of the nine months ended September 30, 2022 and 2021:


	For the Nine Months Ended
	September 30,
(in thousands)	2022		2021		Increase (Decrease)
Revenue	$	42	$	1,133	$	(1,091)	(96)	%
Operating expenses:
Research and development		51,359		54,356		(2,997)	(6)	%
General and administrative		13,329		11,636		1,693	15	%
Impairment loss on construction-in-progress		—		8,070		(8,070)	100	%
Total operating expenses		64,688		74,062		(9,374)	(13)	%
Loss from operations		(64,646)		(72,929)		8,283	11	%
Other income (expense):
Interest expense		(191)		(67)		(124)	(185)	%
Interest income		1,402		88		1,314	1,493	%
Other income (expense), net		185		(293)		478	163	%
Total other income (expense), net		1,396		(272)		1,668	613	%
Net loss before income taxes		(63,250)		(73,201)		9,951	14	%
Income tax benefit		197		—		197
Net loss	$	(63,053)	$	(73,201)	$	10,148	14	%

Revenue

Revenue consists primarily of research grants in the United States from MTEC for our T-COVID product candidate and BARDA for our NasoShield vaccine product candidate. These grants consist of firm fixed fee contracts based on milestones and cost reimbursement contracts, with a fixed fee based on either costs incurred or milestones met. Our T-COVID and NasoShield programs were discontinued as of the end of 2021.

Revenue decreased by $0.2 million, or 99% for the three months ended September 30, 2022 and $1.1 million, or 96%, for the nine months ended September 30, 2022, as compared to the three and nine months ended September 30, 2021. The decrease was primarily the result of the discontinuation of development work on both T-COVID and NasoShield programs as described above.

Research and development expenses

Research and development expense decreased by $8.9 million, or 31%, for the three months ended September 30, 2022, as compared to the three months ended September 30, 2021. The decrease was primarily the result of:

●

a decrease of $17.9 million due primarily to development activities for our COVID-19 programs, which included AdCOVID and T-COVID (which were discontinued in 2021);

●

a decrease of $1.7 million due to change in the fair value of contingent consideration liability with respect to the acquisition of pemvidutide, which was fully paid on June 10, 2022;

●

an increase of $9.1 million due to the development activities for pemvidutide primarily due to the ongoing NAFLD trials and the MOMENTUM Phase 2 trial in obesity;

●

an increase of $0.2 million due to development activities for HepTcell; and

●

a net increase of $1.4 million due primarily to costs associated with non-project specific research and development costs including employee compensation and facility costs.

Research and development expense decreased by $3.0 million, or 6%, for the nine months ended September 30, 2022, as compared to the nine months ended September 30, 2021. The decrease was primarily the result of:

●

a decrease of $32.1 million due primarily to development activities for our COVID-19 programs, which included AdCOVID and T-COVID (which were discontinued in 2021);

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●

a decrease of $1.5 million due to change in the fair value of contingent consideration liability with respect to the acquisition of pemvidutide, which was fully paid on June 10, 2022;

●

an increase of $25.2 million due to the development activities for pemvidutide primarily due to the ongoing NAFLD trials and initiation of the MOMENTUM Phase 2 trial in obesity;

●

an increase of $2.9 million due to development activities for HepTcell; and

●

a net increase of $2.5 million due primarily to costs associated with non-project specific research and development costs including employee compensation and facility costs.

General and administrative expenses

General and administrative expense increased by $0.3 million, or 8% for the three months ended September 30, 2022, as compared to the three months ended September 30, 2022, primarily due to increase in stock compensation expense. For the nine months ended September 30, 2022, general and administrative expense increased by $1.7 million, or 15%, as compared to the nine months ended September 30, 2021, due primarily to a $1.2 million increase in stock compensation and other labor related costs and $0.4 million increase in professional fees.

Impairment loss on construction-in-progress

Impairment loss on construction-in-progress of $8.1 million reported during the nine months ended September 30, 2021 represents non-cash impairment charges recorded for assets that were previously capitalized in connection with the construction of the Lonza facility and subsequent discontinuation of AdCOVID. There were no such impairment charges reported during the nine months ended September 30, 2022.

Total other income (expense), net

Total other income (expense), net increased by $1.3 million and $1.7 million for the three and nine months ended September 30, 2022, as compared to the three and nine months ended September 30, 2021, respectively, primarily due to increase in interest income earned on our cash equivalents and short-term investments.

Income tax benefit

Income tax benefit of $0.2 million related to interest received and receivable on income tax refunds was recorded during the three and nine months ended September 30, 2022. Other than the income tax benefit related to interest, we did not record an income tax benefit in the three and nine months ended September 30, 2022 and 2021 due to a full valuation allowance.

Liquidity and Capital Resources

Overview

Our primary sources of cash during the nine months ended September 30, 2022 were from equity transactions. Our cash, cash equivalents, restricted cash and short-term investments were $201.9 million as of September 30, 2022. We believe, based on the operating cash requirements and capital expenditures expected for 2022 and 2023, our cash on hand as of September 30, 2022, together with expected cash receipts from our income tax refunds and R&D incentives, are sufficient to fund operations for at least a twelve-month period from the issuance date of our September 30, 2022 consolidated financial statements.

We have not generated any revenues from the sale of any products to date, and there is no assurance of any future revenues from product sales. Our sources of revenue have consisted of grant revenues under our arrangements with BARDA for the development of NasoShield, MTEC for a clinical trial and development work on T-COVID, and to a lesser degree from other licensing arrangements. We have incurred significant losses since we commenced operations. As of September 30, 2022, we had an accumulated deficit of $356.2 million. In addition, we have not generated positive cash flows from operations. We have had to rely on a variety of financing sources, including the issuance of debt and equity

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securities. As capital resources are consumed to fund our research and development activities, we may require additional capital beyond our currently anticipated amounts. In order to address our capital needs, including our planned clinical trials, we must continue to actively pursue additional equity or debt financing, government funding, and monetization of our existing programs through partnership arrangements or sales to third parties.

On December 31, 2020, we filed a shelf registration statement on Form S-3, which was declared effective by the SEC on January 11, 2021. This shelf registration statement covered the offering, issuance and sale by us of up to an aggregate of $250.0 million of our common stock, preferred stock, debt securities, warrants, rights and units (the “2021 Shelf”). As of September 30, 2022, approximately $125.0 million remained available to be sold under the 2021 Shelf.

In June 2020, we were awarded $4.7 million from the U.S. Army Medical Research & Development Command (“USAMRDC”) to fund our Phase 1/2 clinical trial of T-COVID. The competitive award was granted by USAMRDC in collaboration with the Medical Technology Enterprise Consortium (“MTEC”), a 501(c)(3) biomedical technology consortium working in partnership with the Department of Defense (“DoD”). Under the contract, MTEC paid us a firm fixed fee based upon the achievement of certain milestones for conduct and completion of a Phase 1/2 study and research and development work on the replication-deficient adenovirus 5 (“RD-Ad5”) vector vaccine platform. Through September 30, 2022, we have collected approximately $4.7 million in cash under the contract, which completed the full recognition of this award.

In July 2016, we signed a five-year contract with BARDA. The contract, as amended, had a total value of up to $136.8 million to be used to fund clinical development of NasoShield. Under the contract, BARDA paid us a fixed fee and reimbursed certain costs for the research and development of an Ad5-vectored, protective antigen-based intranasal anthrax vaccine through cGMP manufacture and conduct of a Phase 1 clinical trial dose ranging assessment of safety and immunogenicity. The contract consisted of an initial base performance period providing approximately $30.9 million in funding for the period July 2016 through December 2021. BARDA had seven options to extend the contract to fund certain continued development and manufacturing activities for the anthrax vaccine, including Phase 2 clinical trials. Each option, if exercised by BARDA, would have provided additional funding ranging from approximately $1.1 million to $34.4 million for a three-year period beginning in 2021. Through September 30, 2022, we have collected approximately $29.3 million in cash under the BARDA contract. BARDA did not extend the contract beyond the end of December 2021.

Cash Flows

The following table provides information regarding our cash flows for the nine months ended September 30, 2022 and 2021:


	Nine Months Ended September 30,
(in thousands)	2022		2021
Net cash (used in) provided by:
Operating activities	$	(45,280)	$	(56,271)
Investing activities		(74,380)		62,654
Financing activities		56,824		52,563
Net (decrease) increase in cash and cash equivalents and restricted cash	$	(62,836)	$	58,946

Operating Activities

Net cash used in operating activities was $45.3 million for the nine months ended September 30, 2022 compared to $56.3 million during the nine months ended September 30, 2021. The primary uses of cash from our operating activities include payments for labor and labor-related costs, professional fees, research and development costs associated with our clinical trials and other general corporate expenditures. The decrease in cash used in operations of $11.0 million year over year is due to changes in working capital accounts of $9.3 million and a decrease in net loss as adjusted for non-cash items of $1.7 million.

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Investing Activities

Net cash used in investing activities was $74.4 million for the nine months ended September 30, 2022 compared to $62.7 million net cash provided during the nine months ended September 30, 2021. The net cash used in investing activities during the nine months ended September 30, 2022 was primarily due to purchase of short-term investments. The net cash provided by investing activities during the nine months ended September 30, 2021 was primarily due to $74.8 million net proceeds from short-term investment activity, partially offset by a $12.0 million purchases of property and equipment.

Financing Activities

Net cash provided by financing activities during the nine months ended September 30, 2022 was $56.8 million compared to $52.6 million for the nine months ended September 30, 2021. The net cash provided by financing activities during the nine months ended September 30, 2022 was primarily the result of the receipt of $56.2 million in net proceeds from the issuance of common stock from our at-the-market offerings program and $0.5 million in net proceeds from exercise of stock options. The net cash provided by financing activities during the nine months ended September 30, 2021 was primarily the result of the receipt of $52.4 million in net proceeds from the issuance of common stock from our at-the-market offerings program.

Financing

Public Offering

On July 16, 2020, we offered and sold (i) 3,369,564 shares of our common stock, at a price to the public of $23.00 per share, and (ii) pre-funded warrants to purchase 1,630,436 shares of our common stock at an exercise price equal to $0.0001 per share (the “Pre-Funded Warrants”), at a price to the public of $22.9999 per share of common stock underlying the Pre-Funded Warrants (equal to the public offering price per share of Common Stock, minus the exercise price of each Pre-Funded Warrant). The Pre-Funded Warrants are exercisable at any time, provided that each Pre-Funded Warrant holder will be prohibited from exercising such Pre-Funded Warrants into shares of our common stock if, as a result of such exercise, the holder, together with its affiliates, would own more than 4.99% of the total number of shares of our common stock then issued and outstanding, which percentage may change at the holders’ election to any other number less than or equal to 19.99% upon 61 days’ notice to us. The gross proceeds of this offering were approximately $132.2 million, which includes the exercise in full of the underwriters’ option to purchase an additional 750,000 shares of common stock, before deducting underwriting discounts and commissions and offering expenses during the third quarter of 2020. The net proceeds of this offering were approximately $124.0 million, after deducting underwriting discounts and commissions and offering expenses payable by us. As of September 30, 2022, 760,870 of the Pre-Funded Warrants were exercised, leaving 869,566 remaining Pre-Funded Warrants unexercised.

At-the-Market Offerings

On February 25, 2021, we entered into an Equity Distribution Agreement (the “2021 Agreement”) with Piper Sandler & Co., Evercore Group L.L.C. and B. Riley Securities, Inc., serving as sales agents (the “Sales Agents”) with respect to an at-the-market offerings program under which we offered and sold shares of our common stock, par value $0.0001 per share (the “Common Stock”), having an aggregate offering price of up to $125.0 million through the Sales Agents from the 2021 Shelf.

During the nine months ended September 30, 2022, we sold 5,204,415 shares of Common Stock under the 2021 Agreement resulting in approximately $56.2 million in net proceeds. As of September 30, 2022, we sold 10,004,869 shares of Common Stock under the 2021 Agreement resulting in approximately $121.0 million in net proceeds. As of September 30, 2022, there were no remaining shares available for issuance under the 2021 Agreement.

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Current Resources

We have financed our operations to date principally through our equity offerings and proceeds from issuances of our preferred stock, common stock and warrants. As of September 30, 2022, we had $127.5 million of cash, cash equivalents and restricted cash and $74.4 million of short-term investments. Accordingly, management believes that we have sufficient capital to fund our plan of operations for at least a twelve-month period from the issuance date of our September 30, 2022 financial statements. However, in order to address our capital needs in the long-term, including potential future clinical trials, we must continue to actively pursue additional equity or debt financing, government funding, and monetization of our existing programs through partnership arrangements or sales to third parties.

Off-Balance Sheet Arrangements

We did not have during the periods presented, and we do not currently have, any off-balance sheet arrangements, as defined in the rules and regulations of the Securities and Exchange Commission.

Item 3. Quantitative and Qualitative Disclosures about Market Risk

As a “smaller reporting company” as defined by Item 10 of Regulation S-K, we are not required to provide the information required by this Item.

Item 4. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure controls and procedures pursuant to Rule 13a-15 under the Securities Exchange Act of 1934, as amended (“the “Exchange Act”) as of the end of the period covered by this Quarterly Report on Form 10-Q.

Based on this evaluation, our principal executive officer and principal financial officer concluded that, as of September 30, 2022, our disclosure controls and procedures were effective to provide reasonable assurance that information we are required to disclose in reports that we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms, and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate, to allow timely decisions regarding required disclosure.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting (as defined in Rule 13a-15(f) and Rule 15d-15(f) under the Exchange Act) during the quarter ended September 30, 2022 identified in connection with the evaluation thereof by our management, including the Chief Executive Officer and Chief Financial Officer, that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

PART II. OTHER INFORMATION

Item 1. Legal Proceedings

From time to time, we may be involved in various legal proceedings arising from the normal course of business activities. Defending such proceedings is costly and can impose a significant burden on management and employees. The results of any current or future litigation cannot be predicted with certainty, and regardless of the outcome, litigation can have an adverse impact on us because of defense and settlement costs, diversion of management resources, and other factors.

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In December 2019, a complaint was filed by Dr. De-Chu Christopher Tang (“Plaintiff”) against us, which we removed to the United States District Court for the Eastern District of Texas. The Plaintiff amended the complaint in February 2020 to include Vipin K. Garg and David J. Drutz as defendants, in addition to the Company (Dr. Garg, Dr. Drutz, and the Company are collectively referred to as “Defendants”). In December 2021, the Plaintiff refiled the complaint in the United States District Court for the District of Maryland. See Note 14 to the consolidated financial statements appearing in Item 1 of this report for further details.

Item 1A. Risk Factors

There have been no material changes from the risk factors disclosed in our Annual Report on Form 10-K filed with the SEC on March 15, 2022.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

None.

Item 3. Default upon Senior Securities

None.

Item 4. Mine Safety Disclosures

Not applicable.

Item 5. Other Information

None.

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Item 6. Exhibits


		Exhibit Index

Exhibit No.		Description

31.1 †		Certification of Principal Executive Officer Pursuant to SEC Rule 13a-14(a)/15d-14(a)

31.2 †		Certification of Principal Financial Officer Pursuant to SEC Rule 13a-14(a)/15d-14(a)

32.1 †		Certification Pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code

32.2 †		Certification Pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code

101.INS		Inline XBRL Instance Document (the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document)

101.SCH		Inline XBRL Taxonomy Extension Schema Document

101.CAL		Inline XBRL Taxonomy Extension Calculation Linkbase Document

101.DEF		Inline XBRL Taxonomy Extension Definition Linkbase Document

101.LAB		Inline XBRL Taxonomy Extension Label Linkbase Document

101.PRE		Inline XBRL Taxonomy Extension Presentation Linkbase Document

104		Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)

†

This certification will not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section. Such certification will not be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except to the extent specifically incorporated by reference into such filing.

§	Certain portions of this exhibit have been omitted pursuant to a request for confidential treatment.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused the report to be signed on its behalf by the undersigned, thereunto duly authorized.


	ALTIMMUNE, INC.

Dated: November 10, 2022	By:	/s/ Vipin K. Garg
	Name:	Vipin K. Garg
	Title:	President and Chief Executive Officer (Principal Executive Officer)

Dated: November 10, 2022	By:	/s/ Richard Eisenstadt
	Name:	Richard Eisenstadt
	Title:	Chief Financial Officer (Principal Financial and Accounting Officer)

Exhibit 31.1

Certification of Principal Executive Officer

Pursuant to SEC Rule 13a-14(a)/15d-14(a)

I, Vipin K. Garg, certify that:

1.	I have reviewed this report on Form 10-Q of Altimmune, Inc. for the period ended September 30, 2022;

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;

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.


Dated: November 10, 2022	/s/ Vipin K. Garg
	Name: Vipin K. Garg
	Title: President and Chief Executive Officer (Principal Executive Officer)

Exhibit 31.2

Certification of Principal Financial Officer

Pursuant to SEC Rule 13a-14(a)/15d-14(a)

I, Richard Eisenstadt, certify that:

1.	I have reviewed this report on Form 10-Q of Altimmune, Inc. for the period ended September 30, 2022;

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;

(a)

(b)

(c)

(d)

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)

(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.


Dated: November 10, 2022	/s/ Richard Eisenstadt
	Name: Richard Eisenstadt
	Title: Chief Financial Officer (Principal Financial Officer)

Exhibit 32.1

Certification Pursuant to Section 1350 of Chapter 63

of Title 18 of the United States Code

In connection with the quarterly report on Form 10-Q of Altimmune, Inc. (the “Company”) for the period ended September 30, 2022, as filed with the Securities and Exchange Commission (the “Report”), I, Vipin K. Garg, President and 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 to the best of my knowledge:

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

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


/s/ Vipin K. Garg
Vipin K. Garg
President and Chief Executive Officer
November 10, 2022

A signed original of this written statement required by Section 906 of the Sarbanes-Oxley Act of 2002 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

This certification is being furnished pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, or otherwise subject to the liability of that section. This certification will not be deemed to be incorporated by reference into any filing under the Securities Act of 1933 or the Securities Exchange Act of 1934.

Exhibit 32.2

Certification Pursuant to Section 1350 of Chapter 63

of Title 18 of the United States Code

In connection with the quarterly report on Form 10-Q of Altimmune, Inc. (the “Company”) for the period ended September 30, 2022, as filed with the Securities and Exchange Commission (the “Report”), I, Richard Eisenstadt, 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 to the best of my knowledge:

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

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


/s/ Richard Eisenstadt
Richard Eisenstadt
Chief Financial Officer
November 10, 2022

Document and Entity Information - shares

CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)
$ in Thousands

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($)
$ in Thousands

Common Stock [Member]

Additional Paid-In Capital [Member]

Accumulated Deficit [Member]

Accumulated Other Comprehensive Loss [Member]

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands

Nature of Business and Basis of Presentation

Summary of Significant Accounting Policies

Fair Value Measurements

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Operating Leases

Accrued Expenses

Contingent Consideration

Below is a summary of the contingent consideration activity (in thousands):


	Nine Months Ended September 30,
	2022		2021
Beginning balance	$	6,090	$	5,390
Change in fair value		86		1,560
Fair value of payments settled in common stock (Phase II Milestone)		(6,176)		—
Ending balance	$	—	$	6,950

Other Long-Term Liabilities

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (b)
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 505
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-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Stock-Based Compensation

U.S. Government Contracts and Grants

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Net Loss Per Share

Commitments and Contingencies

Summary of Significant Accounting Policies (Policies)

Fair Value Measurements (Tables)

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Operating Leases (Tables)

Accrued Expenses (Tables)

Contingent Consideration (Tables)

Other Long-Term Liabilities (Tables)

Warrants (Tables)

Stock-Based Compensation (Tables)

Net Loss Per Share (Tables)

Fair Value Measurements - Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($)
$ in Thousands

Fair Value Measurements - Schedule of Short Term Investments (Detail)
$ in Thousands

Fair Value Measurements - Additional Information (Detail) - USD ($)
$ in Thousands

Operating Leases - Additional Information (Detail) - USD ($)
$ in Millions

Operating Leases - Summary of Supplemental other Information Related to Operating Leases Balance Sheet (Detail) - USD ($)
$ in Thousands

Accrued Expenses - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($)
$ in Thousands

Contingent Consideration - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands

Contingent Consideration - Summary of Fair Value of Contingent Consideration (Detail) - USD ($)
$ in Thousands

Other Long-Term Liabilities - Summary of Other Long-Term Liabilities (Detail) - USD ($)
$ in Thousands

Common Stock - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands

Warrants - Summary of Warrant Activity (Detail)

Warrants - Additional Information (Detail) - $ / shares

Stock-Based Compensation - Additional Information (Detail) - USD ($)

Stock-Based Compensation - Schedule of Information Related to Stock Options Outstanding (Detail)

Stock-Based Compensation - Schedule of Stock-based Compensation Expense (Detail) - USD ($)
$ in Thousands

U.S. Government Contracts and Grants - Additional Information (Detail) - USD ($)
$ in Thousands

Income Taxes - Additional Information (Detail) - USD ($)
$ in Thousands

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares

Commitments and Contingencies - Additional Information (Details) - USD ($)
$ in Thousands

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2022	Nov. 04, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Trading Symbol	ALT
Entity Registrant Name	ALTIMMUNE, INC.
Entity Central Index Key	0001326190
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		49,159,056
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity File Number	001-32587
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-2726770
Entity Address, Address Line One	910 Clopper Road
Entity Address, Address Line Two	Suite 201S
Entity Address, City or Town	Gaithersburg
Entity Address, State or Province	MD
Entity Address, Postal Zip Code	20878
City Area Code	240
Local Phone Number	654-1450
Document Transition Report	false

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
CONSOLIDATED BALANCE SHEETS
Common stock, par or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	49,161,637	40,993,768
Common stock, shares outstanding	49,161,637	40,993,768

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Mar. 31, 2021	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2022
Assets or liabilities measured at fair value on a non-recurring basis.				$ 0
Non-cash impairment charge			$ 8,070
Lonza Manufacturing Agreement [Member]
Non-cash impairment charge			8,100
Commitment to procure equipment and construction	$ 23,000
Lonza Manufacturing Agreement [Member] \| Construction-In-Progress
Non-cash impairment charge		$ 3,300
Capitalized costs			11,400
Lonza Manufacturing Agreement [Member] \| Construction-In-Progress \| Fair Value, Nonrecurring [Member] \| Level 3 [Member]
Fair value of impaired assets			$ 3,300

Operating Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating Leases
Cash paid for operating lease liabilities			$ 0.4	$ 0.4
Operating lease rent expense	$ 0.1	$ 0.1	$ 0.4	$ 0.4

Contingent Consideration - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				2 Months Ended		9 Months Ended
	Jun. 10, 2022	Nov. 19, 2020	Jul. 12, 2019	Jun. 10, 2022	Nov. 19, 2020	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Common stock issued related to contingent consideration liability						$ 6,176
Estimated future contingent consideration							$ 6,950	$ 6,090	$ 5,390
Change in value of contingent consideration for acquired in-process research and development						86	$ 1,560
Clinical Trial Notification [Member]
Business Acquisition [Line Items]
Common stock issued related to contingent consideration liability		$ 13,600
Shares issued for contingent milestone payment		1,694,906
Period for submission of clinical trial notification		60 days
Submission date of clinical trial notification		Oct. 29, 2020
Clinical Trial Notification [Member] \| Regulatory Milestones [Member]
Business Acquisition [Line Items]
Change in value of contingent consideration for acquired in-process research and development					$ 5,400
Spitfire Pharma, Inc. [Member]
Business Acquisition [Line Items]
Agreement date			Jul. 08, 2019
Unregistered shares of common stock			1,887,250
Up-front consideration			$ 5,000
Spitfire Pharma, Inc. [Member] \| Investigational New Drug Application Milestone [Member]
Business Acquisition [Line Items]
Estimated future contingent consideration			$ 5,000
Estimated future contingent consideration term			60 days
Number of consecutive trading days			20 days
Consideration amount			$ 2.95
Spitfire Pharma, Inc. [Member] \| Investigational New Drug Application and Regulatory Milestones [Member]
Business Acquisition [Line Items]
Estimated future contingent consideration			$ 3,000
Estimated future contingent consideration term			60 days
Number of consecutive trading days			20 days
Consideration amount			$ 3.54
Spitfire Pharma, Inc. [Member] \| Sales Milestones [Member]
Business Acquisition [Line Items]
Estimated future contingent consideration			$ 80,000
License agreement term			10 years
Spitfire Pharma, Inc. [Member] \| Regulatory Milestones [Member]
Business Acquisition [Line Items]
Contingent consideration, percentage of shares released after three months			50.00%
Contingent consideration, percentage of shares released after six months			50.00%
Spitfire Pharma, Inc. [Member] \| Phase Two Milestone [Member]
Business Acquisition [Line Items]
Common stock issued related to contingent consideration liability	$ 7,200
Estimated future contingent consideration						$ 0
Consideration amount	$ 8.55			$ 8.55
Shares issued for contingent milestone payment	847,444
Change in value of contingent consideration for acquired in-process research and development				$ 1,900
Spitfire Pharma, Inc. [Member] \| Clinical Trial Notification [Member]
Business Acquisition [Line Items]
Consideration amount		$ 9.57			$ 9.57
Spitfire Pharma, Inc. [Member] \| Common Stock [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Estimated future contingent consideration			$ 88,000


		Page

PART I. FINANCIAL INFORMATION

Item 1.	Financial Statements	1

	Consolidated Balance Sheets as of September 30, 2022 (unaudited) and December 31, 2021	1

	Consolidated Statements of Operations and Comprehensive Loss for the three and nine months ended September 30, 2022 and 2021 (unaudited)	2

	Consolidated Statements of Changes in Stockholders’ Equity for the three and nine months ended September 30, 2022 and 2021 (unaudited)	3

	Consolidated Statements of Cash Flows for the nine months ended September 30, 2022 and 2021 (unaudited)	5

	Notes to Consolidated Financial Statements (unaudited)	6

Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	16

Item 3.	Quantitative and Qualitative Disclosures about Market Risk	23

Item 4.	Controls and Procedures	23


PART II. OTHER INFORMATION

Item 1.	Legal Proceedings	23

Item 1A.	Risk Factors	24

Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	24

Item 3.	Defaults Upon Senior Securities	24

Item 4.	Mine Safety Disclosures	24

Item 5.	Other Information	24

Item 6.	Exhibits	25

	Signatures	26

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 127,465	$ 190,301
Restricted cash	34	34
Total cash, cash equivalents and restricted cash	127,499	190,335
Short-term investments	74,362
Accounts receivable	633	429
Income tax and R&D incentive receivables	3,720	5,410
Prepaid expenses and other current assets	4,790	7,952
Total current assets	211,004	204,126
Property and equipment, net	1,172	1,448
Intangible assets, net	12,419	12,419
Other assets	682	872
Total assets	225,277	218,865
Current liabilities:
Accounts payable	1,419	2,034
Contingent consideration		6,090
Accrued expenses and other current liabilities	14,323	10,152
Total current liabilities	15,742	18,276
Other long-term liabilities	4,506	1,454
Total liabilities	20,248	19,730
Commitments and contingencies (Note 14)
Stockholders' equity:
Common stock, $0.0001 par value; 200,000,000 shares authorized; 49,161,637 and 40,993,768 shares issued and outstanding as of September 30, 2022 and December 31, 2021, respectively	5	4
Additional paid-in capital	566,551	497,342
Accumulated deficit	(356,224)	(293,171)
Accumulated other comprehensive loss, net	(5,303)	(5,040)
Total stockholders' equity	205,029	199,135
Total liabilities and stockholders' equity	$ 225,277	$ 218,865

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Beginning Balance at Dec. 31, 2020	$ 4	$ 417,337	$ (186,421)	$ (5,044)	$ 225,876
Beginning Balance (in shares) at Dec. 31, 2020	37,142,946
Stock-based compensation		1,218			1,218
Vesting of restricted stock awards including withholding, net		(92)			(92)
Vesting of restricted stock awards including withholding, net (in shares)	(6,349)
Issuance of common stock from Employee Stock Purchase Plan		106			106
Issuance of common stock from Employee Stock Purchase Plan (in shares)	8,733
Issuance of common stock in at the market offerings, net		34,178			34,178
Issuance of common stock in at the market offerings, net (in shares)	2,110,800
Retirement of common stock in exchange for common stock warrant		(7,540)	(9,660)		(17,200)
Retirement of common stock in exchange for common stock warrant (in Shares)	(1,000,000)
Issuance of common stock warrant in exchange for retirement of common stock		17,200			17,200
Issuance of common stock upon cashless exercise of warrants		10			10
Issuance of common stock upon cashless exercise of warrants (in shares)	1,050
Unrealized (loss) gain on short-term investments				5	5
Net loss			(14,864)		(14,864)
Ending Balance at Mar. 31, 2021	$ 4	462,417	(210,945)	(5,039)	246,437
Ending Balance (in shares) at Mar. 31, 2021	38,257,180
Beginning Balance at Dec. 31, 2020	$ 4	417,337	(186,421)	(5,044)	225,876
Beginning Balance (in shares) at Dec. 31, 2020	37,142,946
Unrealized (loss) gain on short-term investments					4
Net loss					(73,201)
Ending Balance at Sep. 30, 2021	$ 4	483,582	(269,282)	(5,040)	209,264
Ending Balance (in shares) at Sep. 30, 2021	39,702,768
Beginning Balance at Mar. 31, 2021	$ 4	462,417	(210,945)	(5,039)	246,437
Beginning Balance (in shares) at Mar. 31, 2021	38,257,180
Stock-based compensation		1,485			1,485
Exercise of stock options		94			94
Exercise of stock options (in shares)	38,217
Vesting of restricted stock awards including withholding, net		(90)			(90)
Vesting of restricted stock awards including withholding, net (in shares)	(7,583)
Issuance of common stock in at the market offerings, net		18,178			18,178
Issuance of common stock in at the market offerings, net (in shares)	1,405,710
Unrealized (loss) gain on short-term investments				1	1
Net loss			(24,827)		(24,827)
Ending Balance at Jun. 30, 2021	$ 4	482,084	(235,772)	(5,038)	241,278
Ending Balance (in shares) at Jun. 30, 2021	39,693,524
Stock-based compensation		1,497			1,497
Exercise of stock options		6			6
Exercise of stock options (in shares)	398
Vesting of restricted stock awards including withholding, net		(124)			(124)
Vesting of restricted stock awards including withholding, net (in shares)	(6,521)
Issuance of common stock from Employee Stock Purchase Plan		119			119
Issuance of common stock from Employee Stock Purchase Plan (in shares)	15,367
Unrealized (loss) gain on short-term investments				(2)	(2)
Net loss			(33,510)		(33,510)
Ending Balance at Sep. 30, 2021	$ 4	483,582	(269,282)	(5,040)	209,264
Ending Balance (in shares) at Sep. 30, 2021	39,702,768
Beginning Balance at Dec. 31, 2021	$ 4	497,342	(293,171)	(5,040)	199,135
Beginning Balance (in shares) at Dec. 31, 2021	40,993,768
Stock-based compensation		2,033			2,033
Exercise of stock options		197			197
Exercise of stock options (in shares)	95,771
Vesting of restricted stock awards including withholding, net		(170)			(170)
Vesting of restricted stock awards including withholding, net (in shares)	17,568
Issuance of common stock from Employee Stock Purchase Plan		113			113
Issuance of common stock from Employee Stock Purchase Plan (in shares)	16,450
Issuance of common stock in at the market offerings, net		2,990			2,990
Issuance of common stock in at the market offerings, net (in shares)	335,485
Issuance of common stock upon cashless exercise of warrants (in shares)	1,760,854
Net loss			(19,430)		(19,430)
Ending Balance at Mar. 31, 2022	$ 4	502,505	(312,601)	(5,040)	184,868
Ending Balance (in shares) at Mar. 31, 2022	43,219,896
Beginning Balance at Dec. 31, 2021	$ 4	497,342	(293,171)	(5,040)	199,135
Beginning Balance (in shares) at Dec. 31, 2021	40,993,768
Unrealized (loss) gain on short-term investments					(263)
Net loss					(63,053)
Ending Balance at Sep. 30, 2022	$ 5	566,551	(356,224)	(5,303)	205,029
Ending Balance (in shares) at Sep. 30, 2022	49,161,637
Beginning Balance at Mar. 31, 2022	$ 4	502,505	(312,601)	(5,040)	184,868
Beginning Balance (in shares) at Mar. 31, 2022	43,219,896
Stock-based compensation		2,048			2,048
Exercise of stock options		403			403
Exercise of stock options (in shares)	152,913
Vesting of restricted stock awards including withholding, net		(80)			(80)
Vesting of restricted stock awards including withholding, net (in shares)	(5,865)
Issuance of common stock in at the market offerings, net	$ 1	21,346			21,347
Issuance of common stock in at the market offerings, net (in shares)	2,157,717
Issuance of common stock related to contingent consideration liability		6,176			6,176
Issuance of common stock related to contingent consideration liability (in shares)	847,444
Unrealized (loss) gain on short-term investments				(120)	(120)
Net loss			(20,107)		(20,107)
Ending Balance at Jun. 30, 2022	$ 5	532,398	(332,708)	(5,160)	194,535
Ending Balance (in shares) at Jun. 30, 2022	46,372,105
Stock-based compensation		2,128			2,128
Exercise of stock options		268			268
Exercise of stock options (in shares)	76,161
Vesting of restricted stock awards including withholding, net		(140)			(140)
Vesting of restricted stock awards including withholding, net (in shares)	(7,744)
Issuance of common stock from Employee Stock Purchase Plan		68			68
Issuance of common stock from Employee Stock Purchase Plan (in shares)	9,945
Issuance of common stock in at the market offerings, net		31,829			31,829
Issuance of common stock in at the market offerings, net (in shares)	2,711,013
Other increase (in shares)	157
Unrealized (loss) gain on short-term investments				(143)	(143)
Net loss			(23,516)		(23,516)
Ending Balance at Sep. 30, 2022	$ 5	$ 566,551	$ (356,224)	$ (5,303)	$ 205,029
Ending Balance (in shares) at Sep. 30, 2022	49,161,637

Fair Value Measurements - Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 74,362
Contingent consideration liability (see Note 6)		$ 6,090	$ 6,950	$ 5,390
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	74,362
Total	198,283	65,634
Contingent consideration liability (see Note 6)	0	6,090
Total		6,090
Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total	123,921	65,634
Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	74,362
Total	74,362
Fair Value, Measurements, Recurring [Member] \| Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration liability (see Note 6)		6,090
Total		6,090
Money Market Funds [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	123,921	65,634
Money Market Funds [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	$ 123,921	$ 65,634

Fair Value Measurements - Schedule of Short Term Investments (Detail) $ in Thousands	Sep. 30, 2022 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 74,625
Unrealized Loss	(263)
Market Value	74,362
United States Treasury Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	17,784
Unrealized Loss	(112)
Market Value	17,672
Commercial Paper and Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	49,931
Unrealized Loss	(124)
Market Value	49,807
Asset Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	6,910
Unrealized Loss	(27)
Market Value	$ 6,883

Operating Leases - Summary of Supplemental other Information Related to Operating Leases Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Operating Leases
Operating lease obligations (see Note 5 and 7)	$ 1,230	$ 1,535
Operating lease right-of-use assets (included in "Other assets" in Balance Sheet)	$ 649	$ 798
Weighted-average remaining lease term (years)	2 years 7 months 6 days	3 years 3 months 18 days
Weighted-average discount rate	7.20%	7.20%

Accrued Expenses - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Accrued Liabilities And Other Liabilities [Abstract]
Accrued professional services	$ 624	$ 396
Accrued payroll and employee benefits	2,110	2,313
Accrued research and development	9,930	6,988
Lease obligation, current portion (see Note 4)	442	411
Income tax payable	1,169
Accrued interest and other	48	44
Total accrued expenses and other current liabilities	$ 14,323	$ 10,152

Common Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended					9 Months Ended		19 Months Ended
	Jan. 24, 2022	Feb. 25, 2021	Jul. 16, 2020	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Dec. 31, 2021
Changes In Equity And Comprehensive Income Line Items [Line Items]
Warrants outstanding				1,015,166					1,015,166		1,015,166	2,776,191
Exercise price of warrants or rights				$ 0.66					$ 0.66		$ 0.66
Proceeds from issuance of common stock in public offering									$ 56,166	$ 52,356
Common stock, par or stated value per share				$ 0.0001					$ 0.0001		$ 0.0001	$ 0.0001
Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights				760,870					760,870		760,870
Warrants outstanding				869,566					869,566		869,566
Exercise price of warrants or rights				$ 0.0001					$ 0.0001		$ 0.0001
Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold				2,711,013	2,157,717	335,485	1,405,710	2,110,800
Exchange Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold	999,984
Number of securities called by warrants or rights		1,000,000
Warrants outstanding	0
Exercise price of warrants or rights		$ 0.0001
Common stock, par or stated value per share		$ 0.0001
Common stock exchanged for pre-funded warrants		1,000,000
Number of warrants exercised	1,000,000
Exchange Warrants [Member] \| Exchanging Stockholders [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Ownership percentage		9.99%
Public Offering [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Gross proceeds from offering including exercise of underwriter's option			$ 132,200
Public Offering [Member] \| Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights			1,630,436
Exercise price of warrants or rights			$ 0.0001
Purchase price of warrants issued			$ 22.9999
Ownership percentage on exercise of warrants without notice, minimum			4.99%
Ownership percentage on exercise of warrants with notice, maximum			19.99%
Notice period to increase ownership percentage on exercise of warrants			61 days
Public Offering [Member] \| Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold			3,369,564
Public offering price, per share			$ 23.00
Over-Allotment Option [Member] \| Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold			750,000
Proceeds from issuance of common stock in public offering			$ 124,000
At-The-Market Offering [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold									5,204,415
Proceeds from issuance of common stock in public offering									$ 56,200
Issuance costs									1,900
At-The-Market Offering [Member] \| Equity Distribution Agreement [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Commission and other offering costs				$ 300					$ 300		$ 300
Remaining shares available for issuance				0					0		0
At-The-Market Offering [Member] \| Equity Distribution Agreement [Member] \| Piper Sandler company and evercore group limited liability company and B Riley Securities inc [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold											10,004,869
Proceeds from issuance of common stock in public offering											$ 121,000
Common stock, par or stated value per share		$ 0.0001
Aggregate offering price		$ 125,000
Issuance costs											$ 4,000

Warrants - Summary of Warrant Activity (Detail)	9 Months Ended
Warrants - Summary of Warrant Activity (Detail)	Sep. 30, 2022 $ / shares shares
Warrants
Warrants outstanding, December 31, 2021	2,776,191
Expired	(155)
Exercises (see Note 8)	(1,760,870)
Warrants outstanding, September 30, 2022	1,015,166
Weighted Average Exercise Price \| $ / shares	$ 0.66
Weighted-Average Remaining Contractual Term (Years)	1 year 2 months 12 days

Warrants - Additional Information (Detail) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Class Of Warrant Or Right [Line Items]
Warrants outstanding	1,015,166	2,776,191
Exercise price of warrants or rights	$ 0.66
Pre-Funded Warrants [Member]
Class Of Warrant Or Right [Line Items]
Warrants outstanding	869,566
Exercise price of warrants or rights	$ 0.0001

Stock-Based Compensation - Schedule of Information Related to Stock Options Outstanding (Detail)	9 Months Ended
	Sep. 30, 2022 USD ($) $ / shares shares
Stock-Based Compensation
Number of Stock Options, Outstanding \| shares	3,528,473
Number of Stock Options, Exercisable \| shares	1,382,587
Number of Stock Options, Unvested \| shares	2,145,886
Weighted-average Exercise Price, Outstanding \| $ / shares	$ 9.09
Weighted-average Exercise Price, Exercisable \| $ / shares	8.75
Weighted-average Exercise Price, Unvested \| $ / shares	$ 9.31
Weighted-average Remaining Contractual Term, Outstanding	5 years 10 months 24 days
Weighted-average Remaining Contractual Term, Exercisable	5 years 9 months 18 days
Weighted-average Remaining Contractual Term, Unvested	6 years
Aggregate Intrinsic Value, Outstanding \| $	$ 16,975
Aggregate Intrinsic Value, Exercisable \| $	7,824
Aggregate Intrinsic Value, Unvested \| $	$ 9,151

U.S. Government Contracts and Grants - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 01, 2021	Jun. 30, 2020	Jul. 31, 2016	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenues				$ 2	$ 158	$ 42	$ 1,133
BARDA Contract [Member]
Duration of contract	3 years		5 years
Amount used to fund clinical development			$ 136,800
BARDA Contract [Member] \| Minimum [Member]
Additional funding for development and manufacturing activities	$ 1,100
BARDA Contract [Member] \| Maximum [Member]
Additional funding for development and manufacturing activities	$ 34,400
MTEC Collaborative Arrangement [Member]
Revenues		$ 4,700
Grant [Member] \| BARDA Contract [Member]
Revenues					$ 100		400
Grant [Member] \| MTEC Collaborative Arrangement [Member]
Revenues				$ 0		$ 0	$ 500
Investment Performance [Member] \| BARDA Contract [Member]
Revenues			$ 30,900

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands	Jul. 12, 2019	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Commitments And Contingencies [Line Items]
Estimated future contingent consideration		$ 6,090	$ 6,950	$ 5,390
Spitfire Pharma, Inc. [Member] \| Sales Milestones [Member]
Commitments And Contingencies [Line Items]
Estimated future contingent consideration	$ 80,000
License agreement term	10 years