Aptevo Therapeutics (APVO) 10-Q 8 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	May 08, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Trading Symbol	APVO
Entity Registrant Name	APTEVO THERAPEUTICS INC.
Entity Central Index Key	0001671584
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Transition Report	false
Document Quarterly Report	true
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding		4,080,169
Title of 12(b) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NASDAQ
Entity Address, Address Line One	2401 4th Avenue
Entity Address, Address Line Two	Suite 1050
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98121
City Area Code	206
Local Phone Number	838-0500
Entity Incorporation, State or Country Code	DE
Entity Current Reporting Status	Yes
Entity Tax Identification Number	81-1567056
Entity File Number	001-37746

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 10,250	$ 16,904
Prepaid expenses	1,133	1,473
Other current assets	691	689
Total current assets	12,074	19,066
Property and equipment, net	789	895
Operating lease right-of-use asset	4,766	4,881
Total assets	17,629	24,842
Current liabilities:
Accounts payable and other accrued liabilities	3,720	3,984
Accrued compensation	1,610	2,098
Other current liabilities	968	1,142
Total current liabilities	6,298	7,224
Other long-term liabilities	14
Operating lease liability	5,214	5,397
Total liabilities	11,526	12,621
Stockholders' equity:
Preferred stock: $0.001 par value; 15,000,000 shares authorized, zero shares issued or outstanding
Common stock: $0.001 par value; 500,000,000 shares authorized; 673,430 and 442,458 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	66	61
Additional paid-in capital	236,318	235,607
Accumulated deficit	(230,281)	(223,447)
Total stockholders' equity	6,103	12,221
Total liabilities and stockholders' equity	$ 17,629	$ 24,842

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	15,000,000	15,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	673,430	442,458
Common stock, shares outstanding	673,430	442,458

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating expenses:
Research and development	$ (3,752,000)	$ (4,168,000)
General and administrative	(3,231,000)	(3,588,000)
Loss from operations	(6,983,000)	(7,756,000)
Other income (expense):
Other income (expense) from continuing operations, net	149,000	(67,000)
Gain related to sale of non-financial asset		9,650,000
Net (loss) income from continuing operations	(6,834,000)	1,827,000
Discontinued operations:
Income from discontinued operations	0	946,000
Net (loss) income	$ (6,834,000)	$ 2,773,000
Basic and diluted net (loss) income per share from continuing operations:
Basic	$ (9.95)	$ 11.45
Diluted	(9.95)	11.45
Basic net (loss) income per share	(9.95)	17.38
Diluted net (loss) income per share	$ (9.95)	$ 17.38
Shares used in calculation:
Basic shares used in calculation	686,735	159,597
Diluted shares used in calculation	686,735	159,597

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities
Net (loss) income	$ (6,834)	$ 2,773
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Stock-based compensation	719	915
Depreciation and amortization	106	178
Non-cash interest expense and other		10
Changes in operating assets and liabilities:
Royalty receivable		2,500
Prepaid expenses and other current assets	338	(841)
Operating lease right-of-use asset	115	103
Accounts payable, accrued compensation and other liabilities	(926)	(909)
Long-term operating lease liability	(169)	(163)
Net cash (used in) provided by operating activities	(6,651)	4,566
Financing Activities
Payments of long-term debt, including fees		(3,467)
Value of equity awards withheld for tax liability		(8)
Proceeds from issuance of common stock		1,602
Payments in lieu of fractional shares	(3)
Net cash (used in) provided by financing activities	(3)	(1,873)
(Decrease) increase in cash and cash equivalents	(6,654)	2,693
Cash and cash equivalents at beginning of period	16,904	22,635
Cash and cash equivalents at end of period	$ 10,250	$ 25,328

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Balance at Dec. 31, 2022	$ 17,974	$ 48	$ 223,962	$ (206,036)
Balance (in shares) at Dec. 31, 2022		146,961
Common stock issued upon vesting of restricted stock units	(8)		(8)
Common stock issued upon vesting of restricted stock units (in shares)		961
Issuances of common stock	1,602	$ 1	1,601
Issuances of common stock (in shares)		16,611
Stock-based compensation	915		915
Net income (loss) for the period	2,773			2,773
Balance at Mar. 31, 2023	23,256	$ 49	226,470	(203,263)
Balance (in shares) at Mar. 31, 2023		164,533
Balance at Dec. 31, 2023	12,221	$ 61	235,607	(223,447)
Balance (in shares) at Dec. 31, 2023		442,458
Common stock issued upon vesting of restricted stock units (in shares)		213
Issuances of common stock		$ 5	(5)
Issuances of common stock (in shares)		231,130
Payment in lieu of fractional shares in connection with the 1-for-44 reverse stock split effected on March 5, 2024	(3)		(3)
Payment in lieu of fractional shares in connection with the 1-for-44 reverse stock split effected on March 5, 2024 (in shares)		(371)
Stock-based compensation	719		719
Net income (loss) for the period	(6,834)			(6,834)
Balance at Mar. 31, 2024	$ 6,103	$ 66	$ 236,318	$ (230,281)
Balance (in shares) at Mar. 31, 2024		673,430

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited)(Parenthetical)		3 Months Ended
	Feb. 27, 2024	Mar. 31, 2024
Statement of Stockholders' Equity [Abstract]
Reverse stock split	0.02	0.02

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (6,834)	$ 2,773

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false

Nature of Business and Signific

Nature of Business and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Nature of Business and Significant Accounting Policies	Note 1. Nature of Business and Significant Accounting Policies Organization and Liquidity Aptevo Therapeutics Inc. (Aptevo, we, us, or the Company) is a clinical-stage, research and development biotechnology company focused on developing novel immuno-oncology candidates for the treatment of different forms of cancer. We have developed two versatile and enabling platform technologies for rational design of precision immune modulatory drugs. Our clinical candidates, APVO436 and ALG.APV-527, and preclinical candidates, APVO603 and APVO711, were developed using our ADAPTIR™ modular protein technology platform. Our preclinical candidate APVO442 was developed using our ADAPTIR-FLEX™ modular protein technology platform. We are currently trading on the Nasdaq Capital Market under the symbol “APVO.” The accompanying financial statements have been prepared on a basis that assumes we will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the normal course of business. The consolidated financial statements do not include any adjustments that might result from the outcome of the uncertainty of our ability to continue as a going concern, nor do they include adjustments to reflect the possible future effects of the recoverability and classification of recorded asset amounts and classifications of liabilities that might be necessary should the Company be unable to continue as a going concern. For the three months ended March 31, 2024 , we had a net loss of $ 6.8 million. We had an accumulated deficit of $ 230.3 million as of March 31, 2024. For the three months ended March 31, 2024 , net cash used in our operating activities was $ 6.7 million. We have suffered recurring losses from operations and negative cash flows from operating activities. When considered in aggregate, these factors raise substantial doubt about our ability to continue as a going concern for the one-year period from the date of issuance of these financial statements. We will need to raise additional funds to support our operating and capital needs in addition to our existing cash resources, cash to be generated from future milestones related to IXINITY sales and regulatory approvals achieved by Medexus Pharmaceuticals ("Medexus"), and exercise of common warrants. We may choose to raise additional funds to support our operating and capital needs in the future. We continue to face significant challenges and uncertainties and, as a result, our available capital resources may be consumed more rapidly than currently expected due to: (a) changes we may make to the business that affect ongoing operating expenses; (b) changes we may make in our business strategy; (c) changes we may make in our research and development spending plans; (d) whether and to what extent potential milestones are received from Medexus with respect to IXINITY; (e) macroeconomic conditions such as rising interest rates, inflation and costs; and (f) other items affecting our forecasted level of expenditures and use of cash resources. We may attempt to obtain other public or private financing, collaborative or licensing arrangements with strategic partners, or through credit lines or other debt financing sources to increase the funds available to fund operations. However, we may not be able to secure such funding in a timely manner or on favorable terms, if at all. Furthermore, if we issue equity or debt securities to raise additional funds, our existing stockholders may experience dilution, and the new equity or debt securities may have rights, preferences, and privileges senior to those of our existing stockholders. If we raise additional funds through collaboration, licensing, or other similar arrangements, it may be necessary to relinquish valuable rights to our potential products or proprietary technologies, or grant licenses on terms that are not favorable to us. Without additional funds, we may be forced to delay, scale back, or eliminate some of our research and development activities or other operations and potentially delay product development in an effort to provide sufficient funds to continue our operations. If any of these events occurs, our ability to achieve our development goals may be adversely affected. Given the continuing global economic and geopolitical climate, including rising interest rates and stock market volatility, we may experience delays or difficulties in the financing environment and raising capital due to economic uncertainty. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). These unaudited condensed consolidated financial statements include all adjustments, which include normal recurring adjustments, necessary for the fair presentation of the Company’s financial position. These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements as of and for the year ended December 31, 2023, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates and changes in these estimates are recorded when known. The unaudited condensed consolidated financial statements include the accounts of the Company and our wholly owned subsidiary, Aptevo Research and Development LLC. All intercompany balances and transactions have been eliminated. Use of Estimates The preparation of financial statements in conformity with GAAP requires estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and related disclosures of contingent liabilities in the unaudited condensed financial statements and accompanying notes. Estimates are used for, but not limited to, clinical accruals, useful lives of equipment, commitments and contingencies, stock-based compensation, and incremental borrowing rate (IBR) used for our lease. Given the global economic and geopolitical climate, these estimates are becoming more challenging, and actual results could differ materially from those estimates. Significant Accounting Policies Gain Related to Sale of Nonfinancial Asset to XOMA (US) LLC On March 29, 2023, we entered into and closed a payment interest purchase agreement (the “Purchase Agreement”) with XOMA (US) LLC (“XOMA”) pursuant to which we sold to XOMA our right, title and interest in all of the deferred payments and a portion of the milestone payments from Medexus pursuant to our LLC Purchase Agreement with Medexus, dated February 28, 2020 (the "LLC Agreement"). Under the terms of the Purchase Agreement, we received $ 9.6 million at closing (the “Closing Payment”) and an additional post-closing payment of $ 0.05 . We accounted for the $ 9.6 million Closing Payment and the $ 0.05 million post-closing payment from XOMA as other income in accordance with Accounting Standards Codification ("ASC") 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets in the first quarter of 2023. Contractual rights sold to XOMA represent an intangible asset under ASC 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets for which XOMA bears all benefit and Aptevo has no obligations going forward. The Company will continue to account for its portion of future milestones under our LLC Purchase Agreement with Medexus as contingent consideration under ASC 450-30 Gain Contingencies and will record income when proceeds are received. Other Significant Accounting Policies Our other significant accounting policies were reported in our Annual Report on Form 10-K for the year ended December 31, 2023 that was filed with the SEC on March 5, 2024. Our other significant accounting policies have not changed materially from the policies previously reported.

Discontinued Operations

Discontinued Operations	3 Months Ended
	Mar. 31, 2024
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Note 2. Discontinued Operations The accompanying unaudited condensed consolidated financial statements include discontinued operations from the sale of business products and segments. The following table represents the components attributable to income from discontinued operations in the unaudited condensed consolidated statements of operations (in thousands): For the Three Months Ended March 31, 2023 Deferred payment from Medexus $ 523 Gain on contingent consideration from release of escrow related to sale of Aptevo BioTherapeutics 163 Gain on contingent consideration from Kamada 260 Income from discontinued operations $ 946 For the three months ended March 31, 2024 , we did no t record income from discontinued operations. For the three months ended March 31, 2023 , we collected $ 0.5 million in deferred payments from Medexus related to IXINITY sales and $ 0.2 million related to funds released from escrow from the sale of Aptevo BioTherapeutics in 2020. Additionally, we received $ 0.3 million related to the sale of hyperimmune business to Saol (later acquired by Kamada, Ltd.) as a result of the collection of certain accounts receivable.

XOMA Transaction

XOMA Transaction	3 Months Ended
	Mar. 31, 2024
Related Party Transactions [Abstract]
XOMA Transaction	Note 3. XOMA Transaction On March 29, 2023, we entered into and closed a Purchase Agreement with XOMA pursuant to which we sold to XOMA our right, title and interest in and to all of the deferred payments and a portion of the milestone payments from Medexus under our LLC Purchase Agreement. Under the terms of our Purchase Agreement with XOMA, we received $ 9.6 million at closing and an additional post-closing payment of $ 0.05 million. In exchange for the Closing Payment, we sold to XOMA our right, title and interest to the following payments under the LLC Purchase Agreement: (i) 100 % of the Company’s entitlement to receive the deferred payments that may become due and payable following March 29, 2023 (including, for avoidance of doubt, any and all payments earned during Q1 2023), (ii) 25 % of the Company’s entitlement to receive the Canadian Approval Milestone Payment; and (iii) 50 % of the Company’s entitlement to receive the European Approval Milestone Payments and Net Sales Milestone Payment. We accounted for the $ 9.6 million Closing Payment and the $ 0.05 million post-closing payment from XOMA as other income in accordance with ASC 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets in the first quarter of 2023. Contractual rights sold to XOMA represent an intangible asset under ASC 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets for which XOMA bears all benefit and Aptevo has no obligations going forward. The Company will continue to account for its portion of future milestones under our LLC Purchase Agreement with Medexus as contingent consideration under ASC 450-30 Gain Contingencies and will record income when proceeds are received.

Collaboration Agreements

Collaboration Agreements	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaboration Agreements	Note 4. Collaboration Agreements Alligator Bioscience AB On July 20, 2017, our wholly owned subsidiary Aptevo Research and Development LLC ("Aptevo R&D"), entered into a collaboration and option agreement (the "Collaboration Agreement") with Alligator Bioscience AB ("Alligator"), pursuant to which Aptevo and Alligator have been collaboratively developing ALG.APV-527, a first-in-class bispecific antibody candidate simultaneously targeting 4-1BB (CD137), a member of the TNFR superfamily of a costimulatory receptor found on activated T cells, and 5T4, a tumor antigen widely overexpressed in a number of different types of cancer. We assessed the arrangement in accordance with ASC 606 and concluded that the contract counterparty, Alligator, is not a customer. As such the arrangement is not in the scope of ASC 606 and is instead treated as a collaborative agreement under ASC 808 – Collaborative Arrangements ("ASC 808"). In accordance with ASC 808, we concluded that because the Collaboration Agreement is a cost sharing agreement, there is no revenue. For the three months ended March 31, 2024 and 2023 , we recorded approximately $ 0.6 million and $ 0.8 million, which represent our 50 % cost share, in our research and development expense related to the Collaboration Agreement, respectively.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 5. Fair Value Measurements The Company’s estimates of fair value for financial assets and financial liabilities are based on the framework established in the fair value accounting guidance. The framework is based on the inputs used in valuation, it gives the highest priority to quoted prices in active markets and requires that observable inputs be used in the valuations when available. The disclosure of fair value estimates in the fair value accounting guidance hierarchy is based on whether the significant inputs into the valuation are observable. In determining the level of the hierarchy in which the estimate is disclosed, the highest priority is given to unadjusted quoted prices in active markets and the lowest priority to unobservable inputs that reflect the Company’s significant market assumptions. The level in the fair value hierarchy within which the fair value measurement is reported is based on the lowest level input that is significant to the measurement in its entirety. The three levels of the hierarchy are as follows: Level 1— Quoted prices in active markets for identical assets and liabilities; Level 2— Inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3— Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. At March 31, 2024 and December 31, 2023 , we had $ 9.6 million and $ 13.2 million in Level 1 money market funds, respectively. The carrying amounts of our money market funds approximate their fair value. At March 31, 2024 and December 31, 2023 , we did no t have any Level 2 or Level 3 assets.

Cash and Cash Equivalents

Cash and Cash Equivalents	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents	Note 6. Cash and Cash Equivalents The Company’s cash equivalents are highly liquid investments with a maturity of 90 days or less at the date of purchase and include time deposits and investments in money market funds. The following table shows our cash and cash equivalents as of March 31, 2024 and December 31, 2023: March 31, December 31, (in thousands) 2024 2023 Cash $ 663 $ 3,732 Cash equivalents 9,587 13,171 Total cash and cash equivalents $ 10,250 $ 16,904

Leases

Leases	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
Leases	Note 7. Leases Office Space Lease - Operating We have an operating lease related to our office and laboratory space in Seattle, Washington with a term through April 2030 and two options to extend the lease term, each by five years . As of March 31, 2024 , we are not reasonably certain to exercise the two options to extend the lease term and our lease liability is recorded through April 30, 2030. For the three months ended March 31, 2024 and 2023, we recorded $ 0.2 million related to variable lease expense. Components of lease expense: For the Three Months Ended March 31, (in thousands) 2024 2023 Operating lease cost $ 297 $ 297 Total lease cost $ 297 $ 297 Right of use assets acquired under operating leases: As of March 31, As of December 31, (in thousands) 2024 2023 Seattle office lease, including amendment $ 4,766 $ 4,881 Total operating leases $ 4,766 $ 4,881 Lease payments: For the Three Months Ended March 31, (in thousands) 2024 2023 For operating leases $ 344 $ 115 As of March 31, 2024 , the long-term and current portion of the lease liabilities is $ 5.2 million and $ 0.7 million, respectively. As of March 31, 2023 , the long-term and current portion of the lease liabilities were $ 5.9 million and $ 0.6 million, respectively. As of March 31, 2024 , the weighted-average remaining lease term and weighted-average discount rate for operating leases was 6.08 years and 12.03 %.

Reverse Stock Split

Reverse Stock Split	3 Months Ended
	Mar. 31, 2024
Reverse Stock Split [Abstract]
Reverse Stock Split	Note 8. Reverse Stock Split On February 5, 2024, we held a Special Meeting of Stockholders at which our stockholders approved a series of alternate amendments to the Amended and Restated Certificate of Incorporation to effect, at the option of our Board of Directors (the "Board"), a reverse split of Aptevo's common stock at a ratio ranging from 1-for-15 to 1-for-44 , inclusive, with the effectiveness of one of such amendments and the abandonment of the other amendments, or the abandonment of all amendments, to be determined by the Board in its sole discretion following the Special Meeting. The specific 1-for-44 reverse split ratio was subsequently approved by the Board on February 27, 2024. On March 5, 2024, the Company filed a Certificate of Amendment of Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware to effect a 1-for-44 reverse stock split of the Company's outstanding common stock (the "Reverse Stock Split"). The Reverse Stock Split became effective on March 5, 2024 at 5:01 p.m. Eastern Time, and our common stock began trading on the Nasdaq Capital Market, on a split-adjusted basis, at market open on March 6, 2024. No fractional shares were issued as a result of the Reverse Stock Split. Stockholders of record who would otherwise be entitled to receive a fractional share received a cash payment in lieu thereof. We have adjusted all common stock and stock equivalent figures retroactively in this Form 10-Q for all periods presented to reflect the Reverse Stock Split.

Net Income (Loss) per Share

Net Income (Loss) per Share	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Net Income (Loss) per Share	Note 9. Net Income (Loss) per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing the net income (loss) by the weighted-average number of common share equivalents outstanding for the period using the as-if converted method. Shares of the Company's common stock underlying pre-funded warrants and shares held in abeyance resulting from the previous exercise of warrants are included in the calculation of basic and diluted earnings per share because there is little to no consideration required for delivery of shares. For the purpose of this calculation, warrants, stock options and restricted stock units ("RSUs") are only included in the calculation of diluted net income (loss) per share when their effect is dilutive. We utilize the control number concept in the computation of diluted earnings per share to determine whether potential common stock instruments are dilutive. The control number used is income (loss) from continuing operations or income from discontinued operations. The control number concept requires that the same number of potentially dilutive securities applied in computing diluted earnings per share from continuing operations be applied to all other categories of income or loss, regardless of their anti-dilutive effect on such categories. Common stock equivalents include warrants, stock options and unvested RSUs. The following table presents the computation of basic and diluted net (loss) income per share (in thousands, except share and per share amounts): For the Three Months Ended March 31, 2024 2023 Net (loss) income from continuing operations $ ( 6,834 ) $ 1,827 Income from discontinued operations — 946 Net (loss) income $ ( 6,834 ) $ 2,773 Basic and diluted net (loss) income per share from continuing operations: Basic $ ( 9.95 ) $ 11.45 Diluted $ ( 9.95 ) $ 11.45 Basic and diluted net income per share from discontinued operations: Basic $ — $ 5.93 Diluted $ — $ 5.93 Basic and diluted net (loss) income per share: Basic $ ( 9.95 ) $ 17.38 Diluted $ ( 9.95 ) $ 17.38 Shares used in calculation: Basic 686,735 159,597 Diluted 686,735 159,597 The following table represents all potentially dilutive shares: As of March 31, (in thousands) 2024 2023 Warrants 689 7 Outstanding options to purchase common stock 10 10 Unvested RSUs 6 7 We use the treasury stock method when determining dilutive shares. For the three months ended March 31, 2024, the Company was in a net loss position, therefore the share number used to calculate diluted earnings per share is the same as the basic earnings per share. As of March 31, 2023 , we determined that outstanding warrants, options, and RSUs are not dilutive as the exercise and grant prices were higher than our average share price for the three.

Equity

Equity	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Equity	Note 10. Equity August 2023 Public Raise On August 4, 2023, we completed a public offering of common stock and warrants, which included the following: • 50,488 shares of common stock at a price of $ 27.28 per share. • Pre-funded warrants to purchase up to 132,793 shares of common stock at a price of $ 27.28 per with an exercise price of $ 0.001 per share. As of March 31, 2024, all pre-funded warrants have been exercised. • Series A and Series B common warrants to purchase up to an aggregate of 366,562 shares of common stock at an exercise price of $ 27.28 per share. We received net proceeds of $ 4.3 million, net of transaction costs, as a result of this offering. In the fourth quarter of 2023, an aggregate of 322,691 Series A and Series B common warrants were exercised as part of our November 2023 warrant inducement agreement with certain holders of our common warrants. As of March 31, 2024, there were 42,555 Series A and 1,316 Series B common warrants outstanding with an exercise price of $ 27.28 which will expire on August 4, 2028 and February 4, 2025 , respectively. If these warrants are exercised, we will receive up to an additional $ 1.2 million in gross proceeds. November 2023 Warrant Inducement On November 9, 2023, we entered into a warrant inducement agreement (the "Inducement Agreement") with certain holders of our Series A and Series B common warrants issued in connection with our August 2023 public offering to exercise for cash 140,726 Series A and 181,965 Series B common warrants at a reduced exercise price of $ 10.25 . We received $ 3.3 million in gross proceeds from the exercise of these warrants and issued an aggregate of 645,382 new Series A and new Series B warrants as follows: • 281,452 Series A common warrants to purchase an aggregate of up to 281,452 shares of common stock at $ 10.25 per share, of which 140,726 Series A-1 common warrants were immediately exercisable and 140,726 Series A-2 common warrants were exercisable at any time on or after February 5, 2024 . The Series A-1 and Series A-2 common warrants have terms of four years and eight months , and five years , respectively. • 363,930 Series B common warrants to purchase an aggregate of up to 363,930 shares of common stock at $ 10.25 per share, of which 181,965 Series B-1 common warrants were immediately exercisable and 181,695 Series B-2 common warrants were exercisable at any time on or after February 5, 2024 . The Series B-1 and Series B-2 common warrants have terms of fourteen months and twenty-four months , respectively. As of March 31, 2024, there were 140,726 Series A-1, 140,726 Series A-2, 181,965 Series B-1 and 181,965 Series B-2 common warrants outstanding with an exercise price of $ 10.25 per share, and 4,798 shares remain held in abeyance. If these new warrants are exercised, we will receive up to an additional $ 6.6 million in gross proceeds. Equity Distribution Agreement The Company previously entered into an Equity Distribution Agreement with Piper Sandler (the "Equity Distribution Agreement") under which we could issue and sell through Piper Sandler shares of our common stock pursuant to a Registration Statement on Form S-3 which we filed on December 14, 2020, and expired in December 2023. In the three months ended March 31, 2023 , the Company issued 16,611 shares of common stock at an average price of $ 99.43 under the Equity Distribution Agreement. We received $ 1.6 million in proceeds from the issuance of these shares. Rights Plan On November 8, 2020, our Board of Directors (the "Board") approved and adopted a Rights Agreement (the "Rights Agreement"), dated as of November 8, 2020, by and between the Company and Broadridge Corporate Issuer Solutions, Inc., as rights agent, pursuant to which the Board declared a dividend of one preferred share purchase right (each, a "Right") for each outstanding share of the Company’s common stock held by stockholders as of the close of business on November 23, 2020. One Right also will be issued together with each Common Share issued by the Company after November 23, 2020, but before the Distribution Date (as defined in the Rights Agreement) (or the earlier redemption or expiration of the Rights) and, in certain circumstances, after the Distribution Date. When exercisable, each Right initially would represent the right to purchase from the Company one one-thousandth of a share of a newly-designated series of preferred stock , Series A Junior Participating Preferred Stock, par value $ 0.001 per share, of the Company. Subject to various exceptions, the Rights become exercisable in the event any person (excluding certain exempted or grandfathered persons) becomes the beneficial owner of ten percent ( 10 %) or more of the Company’s common stock without the approval of the Board. On November 2, 2023, we entered into Amendment No. 3 to the Rights Agreement and extended the expiration of such agreement to November 4, 2024 and changed the exercise price to $ 2.02 per one one-thousandth of a Series A Junior Participating Preferred Share, subject to adjustment. 2018 Stock Incentive Plan On June 1, 2018, at the 2018 Annual Meeting of the Stockholders, the Company’s stockholders approved a new 2018 Stock Incentive Plan (the "2018 SIP"), which replaced the Restated 2016 Plan on a go-forward basis. All stock options, RSUs or other equity awards granted subsequent to June 1, 2018 have been and will be issued out of the 2018 SIP, which has 0.02 million shares of Aptevo common stock authorized for issuance. The 2018 SIP became effective immediately upon stockholder approval at the 2018 Annual Meeting of the Stockholders. Any shares subject to outstanding stock awards granted under the 2016 SIP that (a) expire or terminate for any reason prior to exercise or settlement; (b) are forfeited because of the failure to meet a contingency or condition required to vest such shares or otherwise return to the Company; or (c) otherwise would have returned to the 2016 SIP for future grant pursuant to the terms of the 2016 Plan (such shares, the “Returning Shares”) will immediately be added to the share reserve under the 2018 SIP as and when such shares become Returning Shares, up to a maximum of 0.02 million shares. On June 7, 2022, at the 2022 Annual Meeting of Stockholders, our stockholders approved the Amended and Restated 2018 SIP to increase the number of shares authorized for issuance under the 2018 SIP by 500,000 shares of common stock. As of March 31, 2024 , there are 1,558 shares available to be granted under the 2018 SIP. Stock options and RSUs under the Amended and Restated 2018 SIP generally vest pro rata over a one-year or three-year period. Stock options terminate ten years from the grant date, though the specific terms of each grant are determined individually. The Company’s executive officers, members of our board of directors, and certain other employees and consultants may be awarded options and/or RSUs with different vesting criteria, and awards granted to non-employee directors will vest over a one-year period. Option exercise and RSU grant prices for new awards granted by the Company equal the closing price of the Company’s common stock on the Nasdaq Capital Market on the date of grant. Stock-Based Compensation Expense Stock-based compensation expense includes amortization of stock options and RSUs granted to employees and non-employees and has been reported in our unaudited condensed consolidated statements of operations as follows: For the Three Months Ended March 31, (in thousands) 2024 2023 Research and development $ 242 $ 310 General and administrative $ 477 $ 605 Total stock-based compensation expense $ 719 $ 915 The Company accounts for stock-based compensation by measuring the cost of employee services received in exchange for all equity awards granted based on the fair value of the award as of the grant date. The Company recognizes the compensation expense over the vesting period. All assumptions used to calculate the grant date fair value of non-employee equity awards are generally consistent with the assumptions used for equity awards granted to employees. In the event the Company terminates any of its consulting agreements, the unvested equity underlying the agreements would also be forfeited. Stock Options Aptevo utilizes the Black-Scholes valuation model for estimating the fair value of all stock options granted. Set forth below are the assumptions used in valuing the stock options granted: For the Three Months Ended March 31, 2024 2023 Expected dividend yield — — Expected volatility — 103.63 % Risk-free interest rate — 4.18 % Expected average life of options — 5 years The Company did no t grant stock options for the three months ended March 31, 2024. For the three months ended March 31, 2023 , management has applied an estimated forfeiture rate of 30 %. The following is a summary of option activity for the three months ended March 31, 2024: Number of Weighted- Weighted- Balance at December 31, 2023 9,946 $ 563.19 7.38 Granted — — — Exercised — — — Forfeited ( 34 ) 709.25 — Outstanding at March 31, 2024 9,912 561.59 7.14 Exercisable March 31, 2024 7,209 679.55 6.64 Vested and expected to vest at March 31, 2024 9,195 593.56 7.03 As of March 31, 2024 , we had $ 0.4 million of unrecognized compensation expense related to options expected to vest over a weighted-average remaining vesting period of 0.9 years. The weighted-average grant date fair value per share of options granted during the three months ended March 31, 2023 was $ 73.83 . The total fair value of stock options vested for the three months ended March 31, 2024 and 2023 was $ 0.8 million and $ 0.9 million, respectively. The aggregate intrinsic value is the total pretax intrinsic value (the difference between the closing stock price of Aptevo’s common stock on the last trading day of March 2024 and the exercise price, multiplied by the number of in the money options) that would have been received by the option holders had all the option holders exercised their options on the last trading day of the quarter. Restricted Stock Units The following is a summary of RSU activity for the three months ended March 31, 2024: Number of Weighted Balance at December 31, 2023 6,342 $ 205.08 Granted 1,643 7.24 Vested ( 2,070 ) 287.68 Forfeited ( 56 ) 69.21 Outstanding and expected to vest at March 31, 2024 5,859 $ 121.72 As of March 31, 2024 , there was $ 0.5 million unrecognized stock-based compensation expense related to unvested RSUs expected to vest over the weighted-average period of 1.21 years. The fair value of each RSU has been determined to be the closing trading price of the Company’s common stock on the date of grant as quoted on the Nasdaq Capital Market.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	Note 11. Subsequent Events On April 10, 2024, we completed a public offering of (i) 926,666 shares of our common stock and accompanying common warrants ("Common Warrants") to purchase up to 1,853,332 shares of common stock at a public offering price of $ 1.35 per share and accompanying Common Warrants and (ii) pre-funded warrants ("Pre-Funded Warrants") to purchase 2,473,334 shares of common stock and accompanying Common Warrants to purchase up to 4,946,668 shares of common stock at a combined public offering price of $ 1.3499 per Pre-funded Warrant and accompanying Common Warrants, which is equal to the public offering price per share of Common Stock and accompanying Common Warrant less the $ 0.0001 per share exercise price of each such Pre-funded Warrant. We received $ 4.6 million in gross proceeds from the offering. Our net proceeds from the offering amounted to approximately $ 4.0 million after deducting offering expenses payable by us, including placement agent and other fees. The Common Warrants have an exercise price of $ 1.35 per share and are exercisable immediately following the date of issuance and will expire in April 2029. If the Common Warrants are exercised, we will receive up to an additional $ 9.2 million in proceeds.

Nature of Business and Signif_2

Nature of Business and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). These unaudited condensed consolidated financial statements include all adjustments, which include normal recurring adjustments, necessary for the fair presentation of the Company’s financial position. These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements as of and for the year ended December 31, 2023, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates and changes in these estimates are recorded when known. The unaudited condensed consolidated financial statements include the accounts of the Company and our wholly owned subsidiary, Aptevo Research and Development LLC. All intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and related disclosures of contingent liabilities in the unaudited condensed financial statements and accompanying notes. Estimates are used for, but not limited to, clinical accruals, useful lives of equipment, commitments and contingencies, stock-based compensation, and incremental borrowing rate (IBR) used for our lease. Given the global economic and geopolitical climate, these estimates are becoming more challenging, and actual results could differ materially from those estimates.
Gain Related to Sale of Nonfinancial Asset	Gain Related to Sale of Nonfinancial Asset to XOMA (US) LLC On March 29, 2023, we entered into and closed a payment interest purchase agreement (the “Purchase Agreement”) with XOMA (US) LLC (“XOMA”) pursuant to which we sold to XOMA our right, title and interest in all of the deferred payments and a portion of the milestone payments from Medexus pursuant to our LLC Purchase Agreement with Medexus, dated February 28, 2020 (the "LLC Agreement"). Under the terms of the Purchase Agreement, we received $ 9.6 million at closing (the “Closing Payment”) and an additional post-closing payment of $ 0.05 . We accounted for the $ 9.6 million Closing Payment and the $ 0.05 million post-closing payment from XOMA as other income in accordance with Accounting Standards Codification ("ASC") 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets in the first quarter of 2023. Contractual rights sold to XOMA represent an intangible asset under ASC 610-20 Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets for which XOMA bears all benefit and Aptevo has no obligations going forward. The Company will continue to account for its portion of future milestones under our LLC Purchase Agreement with Medexus as contingent consideration under ASC 450-30 Gain Contingencies and will record income when proceeds are received.
Other Significant Accounting Policies	Other Significant Accounting Policies Our other significant accounting policies were reported in our Annual Report on Form 10-K for the year ended December 31, 2023 that was filed with the SEC on March 5, 2024. Our other significant accounting policies have not changed materially from the policies previously reported.

Discontinued Operations (Tables

Discontinued Operations (Tables)	3 Months Ended
	Mar. 31, 2024
Discontinued Operations and Disposal Groups [Abstract]
Summary of Reconciliation of Carrying Amounts of Assets and Liabilities and Income (Loss) from Discontinued Operation	The following table represents the components attributable to income from discontinued operations in the unaudited condensed consolidated statements of operations (in thousands): For the Three Months Ended March 31, 2023 Deferred payment from Medexus $ 523 Gain on contingent consideration from release of escrow related to sale of Aptevo BioTherapeutics 163 Gain on contingent consideration from Kamada 260 Income from discontinued operations $ 946

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents [Abstract]
Schedule of Cash and Cash Equivalents	The following table shows our cash and cash equivalents as of March 31, 2024 and December 31, 2023: March 31, December 31, (in thousands) 2024 2023 Cash $ 663 $ 3,732 Cash equivalents 9,587 13,171 Total cash and cash equivalents $ 10,250 $ 16,904

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
Components of Lease Expense	Components of lease expense: For the Three Months Ended March 31, (in thousands) 2024 2023 Operating lease cost $ 297 $ 297 Total lease cost $ 297 $ 297
Summary of Right of Use Assets Acquired Under Operating Leases	Right of use assets acquired under operating leases: As of March 31, As of December 31, (in thousands) 2024 2023 Seattle office lease, including amendment $ 4,766 $ 4,881 Total operating leases $ 4,766 $ 4,881 Lease payments: For the Three Months Ended March 31, (in thousands) 2024 2023 For operating leases $ 344 $ 115

Net Income (Loss) per Share (Ta

Net Income (Loss) per Share (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Computation of Basic and Diluted Net (Loss) Income per Share	The following table presents the computation of basic and diluted net (loss) income per share (in thousands, except share and per share amounts): For the Three Months Ended March 31, 2024 2023 Net (loss) income from continuing operations $ ( 6,834 ) $ 1,827 Income from discontinued operations — 946 Net (loss) income $ ( 6,834 ) $ 2,773 Basic and diluted net (loss) income per share from continuing operations: Basic $ ( 9.95 ) $ 11.45 Diluted $ ( 9.95 ) $ 11.45 Basic and diluted net income per share from discontinued operations: Basic $ — $ 5.93 Diluted $ — $ 5.93 Basic and diluted net (loss) income per share: Basic $ ( 9.95 ) $ 17.38 Diluted $ ( 9.95 ) $ 17.38 Shares used in calculation: Basic 686,735 159,597 Diluted 686,735 159,597
Summary of Potentially Dilutive Shares Excluded from Calculation of Net Loss Per Share	The following table represents all potentially dilutive shares: As of March 31, (in thousands) 2024 2023 Warrants 689 7 Outstanding options to purchase common stock 10 10 Unvested RSUs 6 7

Equity (Tables)

Equity (Tables)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Summary of Stock-based Compensation Expense Includes Amortization of Stock Options and Restricted Stock Units Granted	Stock-based compensation expense includes amortization of stock options and RSUs granted to employees and non-employees and has been reported in our unaudited condensed consolidated statements of operations as follows: For the Three Months Ended March 31, (in thousands) 2024 2023 Research and development $ 242 $ 310 General and administrative $ 477 $ 605 Total stock-based compensation expense $ 719 $ 915
Assumptions used in Valuing the Stock Options Granted under Black-Scholes Valuation Model	Aptevo utilizes the Black-Scholes valuation model for estimating the fair value of all stock options granted. Set forth below are the assumptions used in valuing the stock options granted: For the Three Months Ended March 31, 2024 2023 Expected dividend yield — — Expected volatility — 103.63 % Risk-free interest rate — 4.18 % Expected average life of options — 5 years
Summary of Stock Option Activity	The following is a summary of option activity for the three months ended March 31, 2024: Number of Weighted- Weighted- Balance at December 31, 2023 9,946 $ 563.19 7.38 Granted — — — Exercised — — — Forfeited ( 34 ) 709.25 — Outstanding at March 31, 2024 9,912 561.59 7.14 Exercisable March 31, 2024 7,209 679.55 6.64 Vested and expected to vest at March 31, 2024 9,195 593.56 7.03
Summary of RSU Activity	The following is a summary of RSU activity for the three months ended March 31, 2024: Number of Weighted Balance at December 31, 2023 6,342 $ 205.08 Granted 1,643 7.24 Vested ( 2,070 ) 287.68 Forfeited ( 56 ) 69.21 Outstanding and expected to vest at March 31, 2024 5,859 $ 121.72

Nature of Business and Signif_3

Nature of Business and Significant Accounting Policies - Additional Information (Details)					3 Months Ended		9 Months Ended
	Apr. 10, 2024 USD ($) $ / shares	Nov. 09, 2023 USD ($) $ / shares	Aug. 04, 2023 USD ($) $ / shares	Mar. 29, 2023 USD ($)	Mar. 31, 2024 USD ($) Platform $ / shares	Mar. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Nature Of Business [Line Items]
Number of technology platforms | Platform					2
Net Income (Loss)					$ (6,834,000)	$ 2,773,000
Accumulated deficit					(230,281,000)			$ (223,447,000)
Net cash used in operating activities					(6,651,000)	4,566,000
Income from discontinued operations					0	946,000
Deferred payment from Medexus						523,000
Proceeds from issuance of common stock						1,602,000
Public Offering
Nature Of Business [Line Items]
Proceeds from issuance of common stock			$ 4,300,000
Public Offering | Series A and Series B Common Warrants
Nature Of Business [Line Items]
Warrants exercise price, per share | $ / shares			$ 27.28
Subsequent Event | Public Offering
Nature Of Business [Line Items]
Proceeds from issuance of common stock	$ 4,000,000
Subsequent Event | Warrants
Nature Of Business [Line Items]
Warrants exercise price, per share | $ / shares	$ 0.0001
IXINITY
Nature Of Business [Line Items]
Deferred payment from Medexus						$ 500,000
Payment Interest Purchase Agreement
Nature Of Business [Line Items]
Income from discontinued operations				$ 9,600,000
Additional post-closing payment				$ 50,000
Percentage of entitlement to receive deferred payments				100%
Percentage of entitlement to receive Canadian approval milestone payment				25%
Percentage of entitlement to receive European approval milestone payment				50%
Payment Interest Purchase Agreement | ASC 610-20
Nature Of Business [Line Items]
Income from discontinued operations					9,600,000		$ 9,600,000
Additional post-closing payment					$ 50,000		$ 50,000
Warrant Inducement Agreement | Series A and Series B Common Warrants
Nature Of Business [Line Items]
Warrants exercise price, per share | $ / shares		$ 10.25			$ 10.25
Warrant Inducement Agreement | Warrants
Nature Of Business [Line Items]
Gross proceeds from warrant exercises		$ 3,300,000
Nasdaq Capital Market
Nature Of Business [Line Items]
Net Income (Loss)					$ 6,800,000
Accumulated deficit					230,300,000
Net cash used in operating activities					$ 6,700,000

Discontinued Operations - Summa

Discontinued Operations - Summary of Reconciliation of Carrying Amounts of Assets and Liabilities and Income (Loss) from Discontinued Operation (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred payment from Medexus		$ 523,000
Income from discontinued operations	$ 0	946,000
Aptevo BioTherapeutics [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred payment from Medexus		200,000
Gain on contingent consideration		163,000
Kamada [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on contingent consideration		$ 260,000

Discontinued Operations - Addit

Discontinued Operations - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred payment		$ 523,000
Income from discontinued operations	$ 0	946,000
Hyperimmune Business
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred payment	$ 300,000
IXINITY
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred payment		500,000
Aptevo BioTherapeutics
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred payment		$ 200,000

XOMA Transaction - Additional I

XOMA Transaction - Additional Information (Details) - USD ($)		3 Months Ended		9 Months Ended
	Mar. 29, 2023	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023
Related Party Transaction [Line Items]
Income from discontinued operations		$ 0	$ 946,000
Payment Interest Purchase Agreement
Related Party Transaction [Line Items]
Income from discontinued operations	$ 9,600,000
Additional post-closing payment	$ 50,000
Percentage of entitlement to receive deferred payments	100%
Percentage of entitlement to receive Canadian approval milestone payment	25%
Percentage of entitlement to receive European approval milestone payment	50%
Payment Interest Purchase Agreement | ASC 610-20
Related Party Transaction [Line Items]
Income from discontinued operations		9,600,000		$ 9,600,000
Additional post-closing payment		$ 50,000		$ 50,000

Collaboration Agreements - Addi

Collaboration Agreements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development expense	$ 0.6	$ 0.8
Percentage of cost related to research and development	50%	50%

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 9,600,000	$ 13,200,000
Level Two
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	0	0
Level Three
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	$ 0	$ 0

Cash and Cash Equivalents - Add

Cash and Cash Equivalents - Additional Information (Details)	3 Months Ended
	Mar. 31, 2024
Restricted Cash And Cash Equivalents Items [Line Items]
Cash equivalents, maturity period	90 days

Cash and Cash Equivalents - Sch

Cash and Cash Equivalents - Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Cash and Cash Equivalents [Abstract]
Cash	$ 663	$ 3,732
Cash equivalents	9,587	13,171
Total cash and cash equivalents	$ 10,250	$ 16,904

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) RenewalOption	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Lessee Lease Description [Line Items]
Operating lease right-of-use asset	$ 4,766		$ 4,881
Long term portion of operating lease liabilities	5,214	$ 5,900	$ 5,397
Current portion of operating lease liabilities	$ 700	$ 600
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current	Other Liabilities, Current
Weighted average remaining lease term for operating leases	6 years 29 days
Weighted discount rate for operating leases	12.03%
Office Space Lease
Lessee Lease Description [Line Items]
Initial operating lease term date	2030-04
Operating lease renewal option description	term through April 2030 and two options to extend the lease term, each by five years
Operating lease renewal option term	5 years
Number of operating lease renewal option | RenewalOption	2
Operating lease option to extend	true
Variable expense	$ 200	$ 200

Leases - Components of Lease Ex

Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Leases [Abstract]
Operating lease cost	$ 297	$ 297
Total lease cost	$ 297	$ 297

Leases - Summary of Right of Us

Leases - Summary of Right of Use Assets Acquired Under Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Lessee Lease Description [Line Items]
Operating lease right-of-use asset	$ 4,766		$ 4,881
For operating leases	344	$ 115
Seattle Office Lease, Including Amendment
Lessee Lease Description [Line Items]
Operating lease right-of-use asset	$ 4,766		$ 4,881

Reverse Stock Split - Additiona

Reverse Stock Split - Additional Information (Details)			3 Months Ended
	Feb. 27, 2024	Feb. 05, 2024	Mar. 31, 2024
Reverse Stock Split [Line Item]
Reverse stock split	0.02		0.02
Reverse Stock Split, outstanding common stock			On March 5, 2024, the Company filed a Certificate of Amendment of Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware to effect a 1-for-44 reverse stock split of the Company's outstanding common stock (the "Reverse Stock Split").
Minimum
Reverse Stock Split [Line Item]
Reverse stock split		0.02
Maximum
Reverse Stock Split [Line Item]
Reverse stock split		0.06

Net Income (Loss) Per Share - C

Net Income (Loss) Per Share - Computation of Basic and Diluted Net (Loss) Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net (loss) income from continuing operations	$ (6,834)	$ 1,827
Income from discontinued operations		946
Net (loss) income	$ (6,834)	$ 2,773
Basic and diluted net (loss) income per share:
Basic net income per share from continuing operations	$ (9.95)	$ 11.45
Diluted net income per share from continuing operations	(9.95)	11.45
Basic net income per share from discontinued operations		5.93
Diluted net income per share from discontinued operations		5.93
Basic net (loss) income per share	(9.95)	17.38
Diluted net (loss) income per share	$ (9.95)	$ 17.38
Shares used in calculation:
Basic shares used in calculation	686,735	159,597
Diluted shares used in calculation	686,735	159,597

Net Income (Loss) Per Share - S

Net Income (Loss) Per Share - Summary of Potentially Dilutive Shares Excluded from Calculation of Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Common Warrants 2019
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	689	7
Outstanding Options to Purchase Common Stock
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	10	10
Unvested RSUs
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	6	7

Equity - Additional Information

Equity - Additional Information (Details) - USD ($)						3 Months Ended
	Apr. 10, 2024	Nov. 09, 2023	Aug. 04, 2023	Nov. 08, 2020	Jun. 01, 2018	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Jun. 07, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from issuance of common stock							$ 1,602,000
Preferred stock, par value						$ 0.001		$ 0.001
Weighted-average grant date fair value per share of options granted							$ 73.83
Total fair value of stock option vested						$ 800,000	$ 900,000
Unvested RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense						$ 500,000
Options expected to vest, weighted average period						1 year 2 months 15 days
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated forfeiture rate							30%
Unrecognized compensation expense						$ 400,000
Options expected to vest, weighted average remaining vesting term						10 months 24 days
Stock options granted						0
2018 Stock Incentive Plan | Unvested RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock authorized for issuance under Stock Plan					20,000				500,000
Maximum number of returning shares from old plan to be add to shares reserve					20,000
Number of shares available for grant						1,558
Stock plan termination period					10 years
2018 Stock Incentive Plan | Unvested RSUs | Non-employee Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period					1 year
Broadridge Corporate Issuer Solutions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Preferred share purchase right				1
Broadridge Corporate Issuer Solutions | Series A Junior Participating Preferred Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Preferred stock, par value				$ 0.001
Share portion entitled to purchase by rights				When exercisable, each Right initially would represent the right to purchase from the Company one one-thousandth of a share of a newly-designated series of preferred stock
Warrants exercise price, per share				$ 2.02
Percentage of beneficial ownership				10%
Minimum | 2018 Stock Incentive Plan | Unvested RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period					1 year
Maximum | 2018 Stock Incentive Plan | Unvested RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period					3 years
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares						231,130	16,611
Warrants | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock price per share	$ 1.35
Warrants exercise price, per share	$ 0.0001
Number of common stock to be issued up conversion of warrants	4,946,668
Warrants | Series A
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share						$ 27.28
Warrants outstanding						42,555
Warrants | Series B
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share						$ 27.28
Warrants outstanding						1,316
Equity Distribution Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock price per share							$ 99.43
Proceeds from issuance of common stock							$ 1,600,000
Equity Distribution Agreement | Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares							16,611
Warrant Inducement Agreement | Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional amount to be received upon exercise of warrants						$ 1,200,000
Gross proceeds from warrant exercises		$ 3,300,000
Warrant Inducement Agreement | Warrants | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional amount to be received upon exercise of warrants	$ 9,200,000
Warrant Inducement Agreement | Warrants | Series A
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding		140,726
Warrant Inducement Agreement | Warrants | Series B
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding		181,965
Pre-funded Warrants | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock price per share	$ 1.3499
Number of common stock to be issued up conversion of warrants	2,473,334
Series A and Series B Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share		$ 10.25				$ 10.25
Number of warrants issued		645,382
Shares remain held in abeyance						4,798
New Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional amount to be received upon exercise of warrants						$ 6,600,000
Series A Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share		$ 10.25
Number of warrants issued		281,452
Series A Common Warrants | Warrant Inducement Agreement | Common Stock | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants		281,452
Series B Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share		$ 10.25
Number of warrants issued		363,930
Series B Common Warrants | Warrant Inducement Agreement | Common Stock | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants		363,930
Series A-1 Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercisable date						Feb. 05, 2024
Number of common stock to be issued up conversion of warrants		140,726
Warrants outstanding, term		4 years 8 months
Warrants outstanding						140,726
Series A-2 Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercisable date						Feb. 05, 2024
Number of common stock to be issued up conversion of warrants		140,726
Warrants outstanding, term		5 years
Warrants outstanding						140,726
Series B-1 Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercisable date						Feb. 05, 2024
Number of common stock to be issued up conversion of warrants		181,965
Warrants outstanding, term		14 months
Warrants outstanding						181,965
Series B-2 Common Warrants | Warrant Inducement Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercisable date						Feb. 05, 2024
Number of common stock to be issued up conversion of warrants		181,695
Warrants outstanding, term		24 months
Warrants outstanding						181,965
Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares			50,488
Common stock price per share			$ 27.28
Proceeds from issuance of common stock			$ 4,300,000
Public Offering | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares	926,666
Proceeds from issuance of common stock	$ 4,000,000
Public Offering | Warrants | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants	1,853,332
Public Offering | Pre-funded Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock price per share			$ 27.28
Warrants exercise price, per share			$ 0.001
Number of common stock to be issued up conversion of warrants			132,793
Public Offering | Series A and Series B Common Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants exercise price, per share			$ 27.28
Number of common stock to be issued up conversion of warrants			366,562

Equity - August 2023 Public Rai

Equity - August 2023 Public Raise - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Aug. 04, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Nov. 09, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Proceeds from issuance of common stock				$ 1,602
Warrant Inducement Agreement | Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional amount to be received upon exercise of warrants		$ 1,200
Series A | Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Warrants exercise price, per share		$ 27.28
Warrants outstanding		42,555
Warrants expiration date	Aug. 04, 2028
Series A | Warrant Inducement Agreement | Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock issued upon exercise of stock options			322,691
Warrants outstanding					140,726
Series B | Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Warrants exercise price, per share		$ 27.28
Warrants outstanding		1,316
Warrants expiration date	Feb. 04, 2025
Series B | Warrant Inducement Agreement | Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock issued upon exercise of stock options			322,691
Warrants outstanding					181,965
Series A and Series B Common Warrants | Warrant Inducement Agreement
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Warrants exercise price, per share		$ 10.25			$ 10.25
Public Offering
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Issuance of common stock shares	50,488
Common stock price per share	$ 27.28
Proceeds from issuance of common stock	$ 4,300
Public Offering | Pre-funded Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock price per share	$ 27.28
Number of common stock to be issued up conversion of warrants	132,793
Warrants exercise price, per share	$ 0.001
Public Offering | Series A and Series B Common Warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants	366,562
Warrants exercise price, per share	$ 27.28

Equity - Summary of Stock-based

Equity - Summary of Stock-based Compensation Expense Includes Amortization of Stock Options and Restricted Stock Units Granted (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 719	$ 915
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	242	310
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 477	$ 605

Equity - Assumptions used in Va

Equity - Assumptions used in Valuing the Stock Options Granted under Black-Scholes Valuation Model (Details) - Employee Stock Option	3 Months Ended
	Mar. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility	103.63%
Risk-free interest rate	4.18%
Expected average life of options	5 years

Equity - Summary of Stock Optio

Equity - Summary of Stock Option Activity (Details) - Employee Stock Option - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning balance	9,946
Number of Shares, Granted	0
Number of Shares, Forfeited	(34)
Number of Shares, Outstanding, Ending balance	9,912	9,946
Number of Shares, Exercisable	7,209
Number of Shares, Vested and expected to Vest	9,195
Weighted-Average Exercise Price, Outstanding, Beginning balance	$ 563.19
Weighted-Average Exercise Price, Forfeited	709.25
Weighted-Average Exercise Price, Outstanding, Ending balance	561.59	$ 563.19
Weighted-Average Exercise Price, Exercisable	679.55
Weighted-Average Exercise Price, Vested and expected to vest	$ 593.56
Weighted-Average Remaining Term, Outstanding	7 years 1 month 20 days	7 years 4 months 17 days
Weighted-Average Remaining Term, Exercisable	6 years 7 months 20 days
Weighted-Average Remaining Term, Vested and expected to vest	7 years 10 days

Equity - Summary of RSU Activit

Equity - Summary of RSU Activity (Details) - Unvested RSUs - $ / shares	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units, Outstanding		6,342
Number of Units, Granted	1,643
Number of Units, Vested	(2,070)
Number of Units, Forfeited	(56)
Number of Units, Outstanding and expected to vest	5,859
Weighted Average Fair Value per Unit, Outstanding		$ 205.08
Weighted Average Fair Value per Unit, Granted	$ 7.24
Weighted Average Fair Value per Unit, Vested	287.68
Weighted Average Fair Value per Unit, Forfeited	69.21
Weighted Average Fair Value per Unit, Outstanding and expected to vest	$ 121.72

Subsequent Events (Additional I

Subsequent Events (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Apr. 10, 2024	Aug. 04, 2023	Mar. 31, 2024	Mar. 31, 2023	Nov. 09, 2023
Subsequent Event [Line Items]
Proceeds from issuance of common stock				$ 1,602
Public Offering
Subsequent Event [Line Items]
Common stock price per share		$ 27.28
Proceeds from issuance of common stock		$ 4,300
Issuance of common stock shares		50,488
Series A and Series B Common Warrants | Public Offering
Subsequent Event [Line Items]
Number of common stock to be issued up conversion of warrants		366,562
Warrants exercise price, per share		$ 27.28
Pre-funded Warrants | Public Offering
Subsequent Event [Line Items]
Number of common stock to be issued up conversion of warrants		132,793
Common stock price per share		$ 27.28
Warrants exercise price, per share		$ 0.001
Warrant Inducement Agreement | New Warrants
Subsequent Event [Line Items]
Additional amount to be received upon exercise of warrants			$ 6,600
Warrant Inducement Agreement | Series A and Series B Common Warrants
Subsequent Event [Line Items]
Warrants exercise price, per share			$ 10.25		$ 10.25
Warrant Inducement Agreement | Warrants
Subsequent Event [Line Items]
Additional amount to be received upon exercise of warrants			$ 1,200
Subsequent Event | Public Offering
Subsequent Event [Line Items]
Gross proceeds from the offering	$ 4,600
Proceeds from issuance of common stock	$ 4,000
Issuance of common stock shares	926,666
Subsequent Event | Pre-funded Warrants
Subsequent Event [Line Items]
Number of common stock to be issued up conversion of warrants	2,473,334
Common stock price per share	$ 1.3499
Subsequent Event | Warrants
Subsequent Event [Line Items]
Number of common stock to be issued up conversion of warrants	4,946,668
Common stock price per share	$ 1.35
Warrants exercise price, per share	$ 0.0001
Subsequent Event | Warrants | Public Offering
Subsequent Event [Line Items]
Number of common stock to be issued up conversion of warrants	1,853,332
Subsequent Event | Warrant Inducement Agreement | Warrants
Subsequent Event [Line Items]
Additional amount to be received upon exercise of warrants	$ 9,200