Note 4 - Balance Sheet Components

3 Months Ended

Mar. 31, 2025

Notes to Financial Statements

Supplemental Balance Sheet Disclosures [Text Block]

NOTE 4.  Balance Sheet Components

(a) Cash, Cash Equivalents and Short-Term Investments

Cash, cash equivalents and investments consisted of the following (in thousands):

	Amortized		Gross Unrealized					Estimated		Cash and Cash		Short-Term
	Cost		Gains		Losses			Fair Value		Equivalents		Investments
March 31, 2025
Cash at banks	$	3,912	$	—	$	—		$	3,912	$	3,912	$	—
Money market funds		24,786		—		—			24,786		24,786		—
U.S. Treasury securities		10,879		—		(7	)		10,872		—		10,872
Commercial paper		2,368		—		—			2,368		—		2,368
Total	$	41,945	$	—	$	(7	)	$	41,938	$	28,698	$	13,240

	Amortized		Gross Unrealized					Estimated		Cash and Cash		Short-Term
	Cost		Gains		Losses			Fair Value		Equivalents		Investments
December 31, 2024
Cash at banks	$	8,740	$	—	$	—		$	8,740	$	8,740	$	—
Money market funds		16,489		—		—			16,489		16,489		—
U.S. Treasury securities		23,802		7		(4	)		23,805		—		23,805
Commercial paper		2,688		1		—			2,689		—		2,689
Total	$	51,719	$	8	$	(4	)	$	51,723	$	25,229	$	26,494

As of March 31, 2025 and December 31, 2024, all investments were available-for-sale debt securities with remaining maturities of 12 months or less. As of  March 31, 2025 and  December 31, 2024, the Company held 7 and 5 securities, respectively, in an unrealized loss position for 12 months or less. Interest receivable as of March 31, 2025 and December 31, 2024, was $0.2 million and $0.2 million, respectively, and is recorded as a component of prepaid expenses and other current assets on the consolidated balance sheets.

(b) Accounts Receivable

Accounts receivable consists of $1.5 million royalty receivable as of March 31, 2025, and $2.7 million of government contract receivables from HHS BARDA and $3.0 million royalty receivable totaling $5.7 million as of December 31, 2024. For further information on HHS BARDA receivables, see Note 5.

The Company has provided no allowance for credit losses as of  March 31, 2025 and December 31, 2024 based on historical collection experience, customer credit worthiness, the age of accounts receivable balances, regulatory changes and current economic conditions and trends that  may affect a customer’s ability to pay.

(c) Unbilled Receivable from Government Contracts

Unbilled receivable, which was earned and not yet billed, consists of government contracts from HHS BARDA of $14.6 million and $6.2 million as of March 31, 2025 and December 31, 2024, respectively, as detailed in Note 5.

(d) Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consist of the following (in thousands):

	March 31, 2025		December 31, 2024
Prepaid clinical and manufacturing expenses	$	1,691	$	1,998
Prepaid insurance		781		282
Prepaid rent		514		521
Other prepaid		1,224		1,449
Other current assets		375		318
Prepaid expenses and other current assets	$	4,585	$	4,568

As of March 31, 2025 there was a significant concentration by two contract research organizations (“CRO”), which represented 35% of the Company’s total prepaid expenses balance. As of  December 31, 2024, there was a significant concentration by one CRO, which represented 28% of the Company’s total prepaid expenses balance.

(e) Property and Equipment, Net

Property and equipment, net consists of the following (in thousands):

	March 31, 2025			December 31, 2024
Laboratory equipment	$	13,910		$	13,806
Office and computer equipment		1,142			1,140
Leasehold improvements		4,107			4,107
Construction in progress		86			160
Total property and equipment		19,245			19,213
Less: accumulated depreciation		(11,424	)		(10,508	)
Property and equipment, net	$	7,821		$	8,705

Depreciation expense was $0.9 million for the three months ended  March 31, 2025 and 2024. There were no impairments of the Company’s property and equipment recorded in the three months ended March 31, 2025 and 2024.

(f) Prepaid Clinical Services, Long-Term

Prepaid clinical services, long-term were $60.1 million as of March 31, 2025 and December 31, 2024. The long-term prepaid clinical services represent amounts the Company has paid to a single CRO that will be utilized in over one year.

(g) Right-of-Use Assets, Net

Right-of-use assets, net comprises facilities of $19.3 million and $20.4 million as of March 31, 2025 and December 31, 2024, respectively. 

(h) Intangible Assets, Net

Intangible assets are comprised of developed technology and intellectual property. Intangible assets are carried at cost less accumulated amortization. As of March 31, 2025, developed technology and intellectual property had remaining lives of 4.6 years and 2.8 years, respectively. As of March 31, 2025, there have been no indicators of impairment.

Intangible assets consist of the following (in thousands):

	March 31, 2025			December 31, 2024
Developed technology	$	5,000		$	5,000
Intellectual property		80			80
Total cost		5,080			5,080
Less: accumulated amortization		(1,705	)		(1,523	)
Intangible assets, net	$	3,375		$	3,557

Intangible asset amortization expense was $0.2 million for the three months ended March 31, 2025 and 2024.

As of March 31, 2025, the estimated future amortization expense by year is as follows (in thousands):

Year Ending December 31,	Amount
2025 (nine months remaining)	$	550
2026		731
2027		731
2028		727
2029		636
Total	$	3,375

(i) Goodwill

Goodwill, which represents the excess of the purchase price over the fair value of assets acquired, was $4.5 million as of both March 31, 2025 and December 31, 2024. As of March 31, 2025, there have been no indicators of impairment.

(j) Accounts Payable

Accounts payable were $16.6 million and $7.0 million as of March 31, 2025 and December 31, 2024, respectively. As of March 31, 2025, there was a significant concentration by two CROs, which represented 90% of the Company’s total accounts payable balance. As of  December 31, 2024, there was a significant concentration by one CRO, which represented 67% of the Company’s total accounts payable balance.

(k) Deferred Government Revenue

Deferred government revenue represents amounts received from HHS BARDA contracts where the earnings process is not yet complete. The Company will recognize deferred government revenue once the earnings process is complete, in accordance with its revenue recognition policies.

The following table represents the Company’s deferred government revenue during the three months ended March 31, 2025 (in thousands):

	March 31, 2025
Balance at beginning of period	$	65,400
Revenue recognized		(47	)
Amounts collected or invoiced		—
Balance at end of period	$	65,353

Amounts collected or invoiced during the year ended  December 31, 2024 primarily relate to amounts received on the 2024 ATI-RRPV Contract (as defined in Note 5) but for which revenue cannot yet be recognized due to contractual milestones not being achieved and the 2024 ASPR-BARDA Contract (as defined in Note 5) budgeted costs that cannot be recognized until project close out.

(l) Other Accrued Current Liabilities

Other accrued current liabilities consist of the following (in thousands):

	March 31, 2025		December 31, 2024
Accrued compensation	$	2,715	$	5,087
Accrued clinical and manufacturing expenses		5,792		5,134
Accrued professional and consulting services		767		623
Other liabilities, current portion		681		534
Total	$	9,955	$	11,378

As of March 31, 2025 and December 31, 2024, there was a significant concentration by one CRO, which represented 46% and 42% of the Company’s total other accrued liabilities balances, respectively.