Chimerix (CMRX) 10-Q 3 Aug 23 2023 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2023	Jul. 28, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-35867
Entity Registrant Name	CHIMERIX, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	33-0903395
Entity Address, Address Line One	2505 Meridian Parkway
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Durham
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27713
City Area Code	919
Local Phone Number	806-1074
Title of each class	Common Stock, par value $0.001 per share
Trading Symbol(s)	CMRX
Name of each exchange on which registered	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	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		88,583,567
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001117480
Current Fiscal Year End Date	--12-31

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 20,099	$ 25,842
Short-term investments, available-for-sale	185,657	191,492
Accounts receivable	26	1,040
Prepaid expenses and other current assets	5,735	9,764
Total current assets	211,517	228,138
Long-term investments	27,258	48,626
Property and equipment, net of accumulated depreciation	256	227
Operating lease right-of-use assets	1,728	1,964
Other long-term assets	326	386
Total assets	241,085	279,341
Current liabilities:
Accounts payable	1,823	3,034
Accrued liabilities	13,518	17,381
Total current liabilities	15,341	20,415
Line of credit commitment fee	125	250
Lease-related obligations	1,507	1,819
Total liabilities	16,973	22,484
Stockholders’ equity:
Preferred stock, $0.001 par value, 10,000,000 shares authorized at June 30, 2023 and December 31, 2022; no shares issued and outstanding as of June 30, 2023 and December 31, 2022	0	0
Common stock, $0.001 par value, 200,000,000 shares authorized at June 30, 2023 and December 31, 2022; 88,583,567 and 88,054,127 shares issued and outstanding as of June 30, 2023 and December 31, 2022, respectively	89	88
Additional paid-in capital	978,213	970,535
Accumulated other comprehensive loss, net	(813)	(337)
Accumulated deficit	(753,377)	(713,429)
Total stockholders’ equity	224,112	256,857
Total liabilities and stockholders’ equity	$ 241,085	$ 279,341

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	88,583,567	88,054,127
Common stock, shares outstanding (in shares)	88,583,567	88,054,127

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Contract and grant revenue	$ 26	$ 440	$ 309	$ 455
Cost of goods sold	0	0	0	114
Gross profit	26	440	309	341
Operating expenses:
Research and development	16,926	18,047	35,748	37,087
General and administrative	4,448	5,840	10,127	11,472
Total operating expenses	21,374	23,887	45,875	48,559
Loss from operations	(21,348)	(23,447)	(45,566)	(48,218)
Other income (loss):
Interest income and other, net	2,772	(21)	5,618	(17)
Net loss	(18,576)	(23,468)	(39,948)	(48,235)
Other comprehensive loss:
Unrealized (loss) gain on debt investments, net	(582)	5	(476)	(47)
Comprehensive loss	$ (19,158)	$ (23,463)	$ (40,424)	$ (48,282)
Per share information:
Net loss, basic (in dollars per share)	$ (0.21)	$ (0.27)	$ (0.45)	$ (0.55)
Net loss, diluted (in dollars per share)	$ (0.21)	$ (0.27)	$ (0.45)	$ (0.55)
Weighted-average shares outstanding, basic (in shares)	88,583,567	87,436,180	88,439,894	87,263,452
Weighted-average shares outstanding, diluted (in shares)	88,583,567	87,436,180	88,439,894	87,263,452
Contract and grant revenue
Contract and grant revenue	$ 26	$ 0	$ 260	$ 0
Licensing revenue
Contract and grant revenue	$ 0	$ 440	$ 49	$ 455

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Gain (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2021	$ 68,252	$ 87	$ 953,782	$ (21)	$ (885,596)
Beginning balance (in shares) at Dec. 31, 2021		86,884,266
Increase (Decrease) in Stockholders' Equity
Share-based compensation	3,708		3,708
Exercise of stock options	102		102
Exercise of stock options (in shares)		34,406
Employee stock purchase plan purchases	555		555
Employee stock purchase plan purchases (in shares)		383,981
RSU stock issuance (in shares)		133,527
Comprehensive loss:
Unrealized gain (loss) on investments, net	(52)			(52)
Net loss	(24,767)				(24,767)
Total comprehensive loss	(24,819)
Ending balance at Mar. 31, 2022	47,798	$ 87	958,147	(73)	(910,363)
Ending balance (in shares) at Mar. 31, 2022		87,436,180
Beginning balance at Dec. 31, 2021	68,252	$ 87	953,782	(21)	(885,596)
Beginning balance (in shares) at Dec. 31, 2021		86,884,266
Comprehensive loss:
Unrealized gain (loss) on investments, net	(47)
Net loss	(48,235)
Total comprehensive loss	(48,282)
Ending balance at Jun. 30, 2022	27,928	$ 87	961,740	(68)	(933,831)
Ending balance (in shares) at Jun. 30, 2022		87,436,180
Beginning balance at Mar. 31, 2022	47,798	$ 87	958,147	(73)	(910,363)
Beginning balance (in shares) at Mar. 31, 2022		87,436,180
Increase (Decrease) in Stockholders' Equity
Share-based compensation	3,593		3,593
Comprehensive loss:
Unrealized gain (loss) on investments, net	5			5
Net loss	(23,468)				(23,468)
Total comprehensive loss	(23,463)
Ending balance at Jun. 30, 2022	27,928	$ 87	961,740	(68)	(933,831)
Ending balance (in shares) at Jun. 30, 2022		87,436,180
Beginning balance at Dec. 31, 2022	$ 256,857	$ 88	970,535	(337)	(713,429)
Beginning balance (in shares) at Dec. 31, 2022	88,054,127	88,054,127
Increase (Decrease) in Stockholders' Equity
Share-based compensation	$ 4,363		4,363
Employee stock purchase plan purchases	357	$ 1	356
Employee stock purchase plan purchases (in shares)		308,000
RSU stock issuance (in shares)		221,440
Comprehensive loss:
Unrealized gain (loss) on investments, net	106			106
Net loss	(21,372)				(21,372)
Total comprehensive loss	(21,266)
Ending balance at Mar. 31, 2023	240,311	$ 89	975,254	(231)	(734,801)
Ending balance (in shares) at Mar. 31, 2023		88,583,567
Beginning balance at Dec. 31, 2022	$ 256,857	$ 88	970,535	(337)	(713,429)
Beginning balance (in shares) at Dec. 31, 2022	88,054,127	88,054,127
Comprehensive loss:
Unrealized gain (loss) on investments, net	$ (476)
Net loss	(39,948)
Total comprehensive loss	(40,424)
Ending balance at Jun. 30, 2023	$ 224,112	$ 89	978,213	(813)	(753,377)
Ending balance (in shares) at Jun. 30, 2023	88,583,567	88,583,567
Beginning balance at Mar. 31, 2023	$ 240,311	$ 89	975,254	(231)	(734,801)
Beginning balance (in shares) at Mar. 31, 2023		88,583,567
Increase (Decrease) in Stockholders' Equity
Share-based compensation	2,959		2,959
Comprehensive loss:
Unrealized gain (loss) on investments, net	(582)			(582)
Net loss	(18,576)				(18,576)
Total comprehensive loss	(19,158)
Ending balance at Jun. 30, 2023	$ 224,112	$ 89	$ 978,213	$ (813)	$ (753,377)
Ending balance (in shares) at Jun. 30, 2023	88,583,567	88,583,567

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (39,948)	$ (48,235)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation of property and equipment	45	48
Amortization of debt issuance costs	132	100
Amortization of discount/premium on investments	(4,002)	74
Share-based compensation	7,324	7,301
Gain on sale of investments	0	(1)
Lease-related amortization	(43)	46
Changes in operating assets and liabilities:
Accounts receivable	1,014	0
Inventories	0	(1,365)
Prepaid expenses and other assets	4,019	917
Accounts payable and accrued liabilities	(5,108)	7,108
Net cash used in operating activities	(36,567)	(34,007)
Cash flows from investing activities:
Purchases of property and equipment	(74)	0
Purchases of short-term investments	(30,347)	(5,258)
Purchases of long-term investments	(15,208)	0
Proceeds from sales of short-term investments	0	7,699
Proceeds from maturities of short-term investments	76,285	57,726
Net cash provided by investing activities	30,656	60,167
Cash flows from financing activities:
Proceeds from exercise of stock options	0	102
Proceeds from employee stock purchase plan	356	556
Payments of debt issuance costs	(188)	(129)
Payment of note payable related to Oncoceutics acquisition	0	(14,000)
Net cash provided by (used in) financing activities	168	(13,471)
Net (decrease) increase in cash and cash equivalents	(5,743)	12,689
Cash and cash equivalents:
Beginning of period	25,842	15,397
End of period	$ 20,099	$ 28,086

The Business and Summary of Sig

The Business and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
The Business and Summary of Significant Accounting Policies	The Business and Summary of Significant Accounting Policies Description of Business Chimerix is a biopharmaceutical company whose mission it is to develop medicines that meaningfully improve and extend the lives of patients facing deadly diseases. Basis of Presentation The accompanying unaudited consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Company’s audited financial statements and notes thereto included in its Annual Report on Form 10-K for the year ended December 31, 2022. In the opinion of the Company’s management, all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of its financial position, operating results and cash flows for the periods presented have been included. Operating results for the three and six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the full year, for any other interim period or for any future year. Fair Value of Financial Instruments The carrying amounts of certain financial instruments, including accounts receivable, accounts payable and accrued expenses approximate their fair values due to the short-term nature of such instruments. For assets and liabilities recorded at fair value, it is the Company’s policy to maximize the use of observable inputs and minimize the use of unobservable inputs when developing fair value measurements, in accordance with the fair value hierarchy. Fair value measurements for assets and liabilities where there exists limited or no observable market data are based primarily upon estimates and are often calculated based on the economic and competitive environment, the characteristics of the asset or liability and other factors. Therefore, fair value measurements cannot be determined with precision and may not be realized in an actual sale or immediate settlement of the asset or liability. Additionally, there may be inherent weaknesses in any calculation technique and changes in the underlying assumptions used, including discount rates and estimates of future cash flows, could significantly affect the calculated current or future fair values. The Company utilizes fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. The Company groups assets and liabilities at fair value in three levels, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. The determination of where an asset or liability falls in the hierarchy requires significant judgment. These levels are: • Level 1 — Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access. • Level 2 — Valuations based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and models for which all significant inputs are observable, either directly or indirectly. • Level 3 — Valuations based on inputs that are unobservable and significant to the overall fair value measurement. There was no material re-measurement to fair value of financial assets and liabilities that are not measured at fair value on a recurring basis. For additional information regarding the Company’s investments, please refer to Note 2, “Investments.” Below are tables that present information about certain assets measured at fair value on a recurring basis (in thousands): Fair Value Measurements June 30, 2023 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 18,142 $ 18,142 $ — $ — Total cash equivalents 18,142 18,142 — — Short-term investments U.S. treasury securities 82,033 37,496 44,537 — Commercial paper 76,124 — 76,124 — Corporate bonds 27,500 — 27,500 — Total short-term investments 185,657 37,496 148,161 — Long-term investments U.S. treasury securities 27,258 2,924 24,334 — Total long-term investments 27,258 2,924 24,334 — Total assets $ 231,057 $ 58,562 $ 172,495 $ — Fair Value Measurements December 31, 2022 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 17,826 $ 17,826 $ — $ — Commercial paper 4,998 — 4,998 — Total cash equivalents 22,824 17,826 4,998 — Short-term investments U.S. treasury securities 38,094 25,271 12,823 — Commercial paper 127,517 — 127,517 — Corporate bonds 25,881 — 25,881 — Total short-term investments 191,492 25,271 166,221 — Long-term investments U.S. treasury securities 48,626 11,685 36,941 — Total long-term investments 48,626 11,685 36,941 — Total assets $ 262,942 $ 54,782 $ 208,160 $ — Inventories The Company considers regulatory approval of product candidates to be uncertain and product manufactured prior to regulatory approval may not be sold unless regulatory approval is obtained. As such, the manufacturing costs for product candidates incurred prior to regulatory approval are not capitalized as inventory but are expensed as research and development costs. The Company begins capitalization of these inventory related costs once regulatory approval is obtained. The Company primarily uses actual costs to determine its cost basis for inventories. On May 15, 2022, we entered into an Asset Purchase Agreement (the Asset Purchase Agreement) with an affiliate of Emergent BioSolutions Inc. (Emergent BioSolutions) for the sale of our exclusive worldwide rights to brincidofovir, including TEMBEXA® and specified related assets (the Asset Sale). On September 26, 2022, we closed the Asset Sale with Emergent Biodefense Operations Lansing LLC (Emergent), an affiliate of Emergent BioSolutions. Prior to the sale of TEMBEXA to Emergent, the Company’s inventory consisted of TEMBEXA, which was being manufactured for the treatment of smallpox for potential delivery to the Strategic National Stockpile (SNS) for the U.S. government and to other government agencies. TEMBEXA was approved by the FDA on June 4, 2021, at which time the Company began to capitalize inventory costs associated with TEMBEXA. Prior to FDA approval of TEMBEXA, all costs related to the manufacturing of TEMBEXA were charged to research and development expense in the period incurred as there was no alternative future use. The Company valued its inventories at the lower of cost or estimated net realizable value. The Company determined the cost of its inventories, which included amounts related to materials, manufacturing costs, shipping and handling costs on a first-in, first-out (FIFO) basis. Work-in-process included all inventory costs prior to packaging and labelling, including raw material, active product ingredient, and drug product. Finished goods included packaged and labelled products. Title to all inventory was transferred to Emergent upon the close of the Asset Sale. Employee Retention Credit Under the provisions of the extension of the Coronavirus Aid, Relief, and Economic Security Act (the CARES Act) passed by the United States Congress and signed by the President, the Company was eligible for a refundable employee retention credit subject to certain criteria. The Company recognized a $2.0 million employee retention credit during the three months ended September 30, 2022 related to labor costs recognized during 2020 and 2021, which is recorded in prepaid expenses and other current assets. For the three months ended September 30, 2022, $1.5 million was recorded as a reduction to research and development expenses and $0.5 million was recorded as a reduction to general and administrative expenses. The Company has filed for refunds of the employee retention credits and as of the date of this Quarterly Report on Form 10-Q, it has received $27,000 of refunds and cannot reasonably estimate when it will receive any or all of the remaining refunds. Deferred Loan Costs On January 31, 2022 (the Effective Date), the Company entered into a Loan and Security Agreement (the Loan Agreement), by and between the Company, as borrower, and Silicon Valley Bank, now a division of First-Citizens Bank & Trust Company, as the lender (the Lender). The Loan Agreement provides for a four-year secured revolving loan facility (the Credit Facility) in an aggregate principal amount of up to $50.0 million. Proceeds from the Credit Facility may be used for working capital and general corporate purposes. The Company has no obligation to draw down any amount under the Credit Facility, and has not drawn down any amount as of June 30, 2023. In September 2022, in connection with the Asset Sale, the Lender and the Company agreed to suspend the availability of future advances under the Loan Agreement until such time the parties mutually agree to amend the Loan Agreement to, among other things, adjust the borrowing base and reset the covenants. Borrowings under the Credit Facility accrue interest at a floating per annum rate of the greater of (i) 1.50% above the Prime Rate (as defined below) and (ii) 4.75%. Prime Rate is defined as the rate of interest per annum published in The Wall Street Journal or any successor publication thereto as the “Prime Rate”. If such rate of interest from The Wall Street Journal becomes unavailable, the “Prime Rate” shall mean the rate of interest per annum announced by the Lender as its prime rate in effect. In each case, in the event such prime rate is less than zero, such rate shall be deemed to be zero for purposes of the Loan Agreement. The Company must also pay an unused line fee equal to 0.25% per annum on the unused portion of the Credit Facility, payable quarterly in arrears. Upon the termination of the Loan Agreement for any reason prior to the Maturity Date, the Company will be required to pay to the Lender an early termination fee of $0.5 million. The Loan Agreement also requires the Company to pay the Lender a non-refundable commitment fee of $0.5 million, payable in four equal installments beginning on the Effective Date and each anniversary of the Effective Date thereafter until January 31, 2025. As of June 30, 2023, the Company has recorded current deferred loan costs of $0.1 million in prepaid expenses and other current assets and non-current deferred loan costs of $0.2 million in other long-term assets on the Consolidated Balance Sheets. As of June 30, 2023, the Company has recorded a current loan fee liability of $0.2 million in accrued liabilities and a non-current loan fee liability of $0.1 million in line of credit commitment fee on the Consolidated Balance Sheets. Accrued Liabilities Accrued liabilities consisted of the following (in thousands): June 30, 2023 December 31, 2022 Accrued research and development expenses $ 7,591 $ 6,691 Accrued compensation 3,649 6,438 Other accrued liabilities 2,278 4,252 Total accrued liabilities $ 13,518 $ 17,381 Revenue Recognition Policy The Company’s revenues generally consist of (i) contract and grant revenue—revenue generated under federal and private foundation grants and contracts, (ii) licensing revenue—revenue related to non-refundable upfront fees, royalties and milestone payments earned under license agreements (iii) royalty revenue—revenue related to sales of TEMBEXA made by Emergent after the Asset Sale, and (iv) procurement revenue—revenue related to sales of TEMBEXA prior to the Asset Sale. Revenue is recognized in accordance with the criteria outlined in Accounting Standards Codification (ASC) 606 issued by the Financial Accounting Standards Board (FASB). Following this accounting pronouncement, a five-step approach is applied for recognizing revenue, including (1) identify the contract with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when, or as, the entity satisfies a performance obligation. Emergent BioSolutions, Inc. On September 26, 2022, the Company completed the Asset Sale to Emergent of the Company’s exclusive worldwide rights to brincidofovir, including TEMBEXA® and specified related assets (the Asset Sale). Emergent paid the Company an upfront cash payment of approximately $238 million upon the closing of the Asset Sale. In addition, pursuant to the Asset Purchase Agreement, the Company is eligible to receive from Emergent: (i) up to an aggregate of approximately $124 million in milestone payments payable upon the exercise of the options under the BARDA Agreement (as defined below) for the delivery of up to 1.7 million treatment courses of tablet and suspension formulations of TEMBEXA to the U.S. government; (ii) royalty payments equal to 15% of all gross profits associated with the sales of TEMBEXA made outside of the United States during the exclusivity period of TEMBEXA on a market-to-market basis; (iii) royalty payments equal to 20% of future gross profits of TEMBEXA made in the United States associated with volumes above 1.7 million treatment courses of therapy during the exclusivity period of TEMBEXA; and (iv) up to an additional $12.5 million upon the achievement of certain other developmental milestones. The BARDA Agreement was novated to Emergent in December 2022. Under the Asset Purchase Agreement, the Company recognized $26,000 and $0.2 million of contract revenue for expense reimbursement related to support provided to Emergent for the three and six months ended June 30, 2023, respectively. Grant Revenue Grant revenue under cost-plus-fixed-fee grants from the federal government and private foundations is recognized as allowable costs are incurred and fees are earned. At June 30, 2023, the Company has a deferred revenue balance of $0.1 million related to these grants. For the three months ended June 30, 2023, the Company recognized no grant revenue and for the six months ended June 30, 2023, the Company recognized $30,000 of grant revenue. For the three and six months ended June 30, 2022, the Company recognized no grant revenue related to these grants. Ohara Agreement In 2019, Oncoceutics, Inc., a Delaware corporation (Oncoceutics) which was subsequently acquired by the Company in January 2021, entered into a license, development and commercialization agreement with Ohara Pharmaceutical Co., Ltd. for ONC201 in Japan. The Company is entitled to receive up to $2.5 million in nonrefundable regulatory milestone payments. The Company is entitled to double-digit tiered royalties based on the aggregate annual net sales of all products, as defined in the agreement, in Japan. For the three months ended June 30, 2023, the Company recognized no license revenue related to this agreement and for the six months ended June 30, 2023, the Company recognized approximately $58,000 of license revenue related to this agreement. For the three and six months ended June 30, 2022, the Company recognized approximately $0.4 million and $0.4 million, respectively, of license revenue related to this agreement. TEMBEXA Procurement Agreements Revenue and Royalty Revenue In June 2022, the Company entered into the Supply Agreement and the PHAC Contract (as defined in Note 6 below), pursuant to which the Company was responsible for supplying TEMBEXA (brincidofovir) treatment courses for use outside of the United States. There are no material performance obligations outside of delivery in the agreements, therefore revenue related to these procurement agreements was recognized when the delivery performance obligation was satisfied. Revenue was recognized based on price per treatment course as outlined in the agreements. For the three months ended September 30, 2022, the Company recognized $32.0 million of procurement revenue related to these agreements. The remaining deliveries of treatment courses related to the PHAC Contract were delivered by Emergent and were subject to the royalty terms of the Asset Purchase Agreement applicable to gross profits outside the United States. The Company recognized approximately $0.4 million of royalty revenue in the three months ended December 31, 2022. Research and Development Prepaids and Accruals As part of the process of preparing financial statements, the Company is required to estimate its expenses resulting from its obligation under contracts with vendors and consultants and clinical site agreements in connection with its research and development efforts. The financial terms of these contracts are subject to negotiations which vary contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to the Company under such contracts. The Company’s objective is to reflect the appropriate research and development expenses in its financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of its research and development efforts. The Company determines prepaid and accrual estimates through discussion with applicable personnel and outside service providers as to the progress or state of communication of clinical trials, or other services completed. The Company adjusts its rate of research and development expense recognition if actual results differ from its estimates. The Company makes estimates of its prepaid and accrued expenses as of each balance sheet date in its financial statements based on facts and circumstances known at that time. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of status and timing of services performed relative to the actual status and timing of services performed may vary and may result in the Company reporting amounts that are too high or too low for any particular period. Through June 30, 2023, there had been no material adjustments to the Company’s prior period estimates of prepaid and accruals for research and development expenses. The Company’s research and development prepaids and accruals are dependent upon the timely and accurate reporting of contract research organizations and other third-party vendors. Basic and Diluted Net Income (Loss) Per Share of Common Stock Basic net income (loss) per share of common stock is computed by dividing net income (loss) by the weighted-average number of shares of common stock outstanding during the period, excluding the dilutive effects of non-vested restricted stock, stock options, and employee stock purchase plan purchase rights. Diluted net income (loss) per share of common stock is computed by dividing net income (loss) by the sum of the weighted-average number of shares of common stock outstanding during the period plus the potential dilutive effects of non-vested restricted stock, stock options, and employee stock purchase plan purchase rights outstanding during the period calculated in accordance with the treasury stock method, but are excluded if their effect is anti-dilutive. Because the impact of these items is anti-dilutive during the periods of net loss, there was no difference between basic and diluted loss per share of common stock for the three and six months ended June 30, 2023 and 2022. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. In addition to estimates discussed in other sections of this Quarterly Report on Form 10-Q, the most significant estimates in the Company’s consolidated financial statements relate to the valuation of stock options and the valuation allowance for deferred tax assets resulting from net operating losses. These estimates are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. Segments The Company operates in only one segment, pharmaceuticals. Impact of Recently Adopted Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which amends the impairment model by requiring entities to use a forward-looking approach on expected losses to estimate credit losses on certain financial instruments, including trade receivables and available-for-sale debt securities. The new guidance was originally due to become effective for the Company beginning in the first quarter of 2020, however the FASB in November 2019 issued ASU 2019-10 which moved the effective date for smaller reporting companies to the first quarter of 2023. The Company adopted ASU 2016-03 as of January 1, 2023. Given the nature of the Company’s receivables and investment portfolio, adoption of this standard had no impact on the Company's financial position, results of operations or cash flows.

Investments

Investments	6 Months Ended
	Jun. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The following tables summarize the Company’s debt investments (in thousands): June 30, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 27,556 $ — $ (56) $ 27,500 Commercial paper 76,211 3 (90) 76,124 U.S. treasury securities 109,961 1 (671) 109,291 Total investments $ 213,728 $ 4 $ (817) $ 212,915 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 25,906 $ 4 $ (29) $ 25,881 Commercial paper 127,657 36 (176) 127,517 U.S. treasury securities 86,892 7 (179) 86,720 Total investments $ 240,455 $ 47 $ (384) $ 240,118 The following tables summarize the Company’s debt investments with unrealized losses, aggregated by investment type and the length of time that individual investments have been in a continuous unrealized loss position (in thousands, except number of securities): June 30, 2023 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 27,500 $ (56) $ — $ — $ 27,500 $ (56) Commercial paper 55,662 (90) — — 55,662 (90) U.S. treasury securities 104,558 (672) — — 104,558 (672) Total $ 187,720 $ (818) $ — $ — $ 187,720 $ (818) Number of securities with unrealized losses 60 — 60 December 31, 2022 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 22,905 $ (29) $ — $ — $ 22,905 $ (29) Commercial paper 88,860 (176) — — 88,860 (176) U.S. treasury securities $ 67,489 $ (179) $ — $ — $ 67,489 $ (179) Total $ 179,254 $ (384) $ — $ — $ 179,254 $ (384) Number of securities with unrealized losses 55 — 55 The Company invests in high credit quality investments in accordance with its investment policy, which is designed to minimize the possibility of loss. The objective of the Company’s investment policy is to ensure the safety and preservation of invested funds, as well as maintaining liquidity sufficient to meet cash flow requirements. The Company places its excess cash with high credit quality financial institutions, commercial companies, and government agencies in order to limit the amount of its credit exposure. In accordance with its policy, the Company is able to invest in marketable debt securities that may consist of U.S. Government and government agency securities, money market and mutual fund investments, certificates of deposits, municipal and corporate notes and bonds, and commercial paper, among others. The Company’s investment policy requires it to purchase high-quality marketable securities with a maximum individual maturity of two years and requires an average portfolio maturity of no more than 12 months. Some of the securities in which the Company invests may have market risk. This means that a change in prevailing interest rates may cause the principal amount of the investment to fluctuate. To minimize this risk, the Company schedules its investments with maturities that coincide with expected cash flow needs, thus avoiding the need to redeem an investment prior to its maturity date. Accordingly, the Company does not believe it has a material exposure to interest rate risk arising from its investments. Generally, the Company’s investments are not collateralized. The Company has not realized any significant losses from its investments. The Company classifies all of its investments as available-for-sale. Unrealized gains and losses on investments are recognized in comprehensive loss, unless an unrealized loss is considered to be other than temporary, in which case the unrealized loss is charged to operations. The Company periodically reviews its investments for other than temporary declines in fair value below cost basis and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company evaluates, among other things, the duration and extent to which the fair value of a security is less than its cost; the financial condition of the issuer and any changes thereto; and the Company’s intent to sell, or whether it will more likely than not be required to sell, the security before recovery of its cost basis. The Company believes the individual unrealized losses represent temporary declines primarily resulting from interest rate changes. Unrealized gains and losses on debt investments are recorded to unrealized gain (loss) on debt investments, net in the Consolidated Statements of Operations and Comprehensive Loss. Realized gains and losses on debt investments are recorded based on specific identification to interest income and other, net in the Consolidated Statements of Operations and Comprehensive Loss. Investments with original maturities at date of purchase beyond three months and which mature at or less than 12 months from the balance sheet date are classified as current investments. Investments with a maturity beyond 12 months from the balance sheet date are classified as long-term investments. At June 30, 2023, the Company believes that the cost of its investments is recoverable in all material respects. The Company recognizes interest income on an accrual basis in interest income in the Consolidated Statements of Operations and Comprehensive Loss. The following table summarizes the scheduled maturity for the Company’s debt investments at June 30, 2023 (in thousands): Maturing in one year or less $ 185,657 Maturing after one year through two years 27,258 Total debt investments $ 212,915

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases The Company leases its facilities under long-term operating leases that expire at various dates through 2026. The Company generally has options to renew lease terms on its facilities, which may be exercised at the Company’s sole discretion. In addition, certain lease arrangements may be terminated prior to their original expiration date at the Company’s discretion. The Company evaluates renewal and termination options at the lease commencement date to determine if it is reasonably certain to exercise the option and has concluded on all operating leases that it is not reasonably certain that any options will be exercised. The weighted-average remaining lease term for the Company’s operating leases as of June 30, 2023 was 3.09 years. Expense related to leases is recorded on a straight-line basis over the lease term. Lease expense under operating leases, including common area maintenance fees, totaled approximately $0.2 million and $0.1 million, respectively, for the three months ended June 30, 2023 and 2022 and $0.3 million and $0.3 million for the six months ended June 30, 2023 and 2022. The discount rate implicit within the Company’s leases is generally not determinable and therefore the Company determines the discount rate based on its incremental borrowing rate based on the information available at commencement date. As of June 30, 2023, the operating lease liabilities reflect a weighted-average discount rate of 7.89%. The following table sets forth the operating lease right-of-use assets and liabilities as of June 30, 2023 (in thousands): Assets Operating lease right-of-use assets $ 1,728 Liabilities Operating lease short-term liabilities (recorded within Accrued liabilities) $ 607 Operating lease long-term liabilities (recorded within Lease-related obligations) 1,507 Total operating lease liabilities $ 2,114 Operating lease payments over the remainder of the lease terms are as follows (in thousands): Years Ending December 31, As of June 30, 2023 2023 371 2024 759 2025 781 2026 467 Total future minimum rental payments $ 2,378 Less amount of lease payments representing interest 264 Total present value of lease payments $ 2,114 As of December 31, 2022, operating lease payments over the remainder of the lease terms were as follows (in thousands): Years Ending December 31, As of December 31, 2022 2023 736 2024 759 2025 781 2026 467 Total future minimum rental payments $ 2,743 Less amount of lease payments representing interest 351 Total present value of lease payments $ 2,392 For the three months ended June 30, 2023 and 2022, the Company made lease payments of approximately $0.2 million and $0.2 million, respectively, and for the six months ended June 30, 2023 and 2022, the Company made lease payments of approximately $0.4 million and $0.3 million, respectively. Significance of Revenue Source The Company was the recipient of federal research contract funds from BARDA, the primary source of the Company’s prior period contract and grant revenue. Periodic audits are required in connection with the Company’s receipt of such funds and certain costs may be questioned as appropriate by BARDA. Accordingly, at June 30, 2023 and December 31, 2022, the Company had recorded a provision for potential refundable amounts of $52,000.

Equity Transactions and Share-b

Equity Transactions and Share-based Compensation	6 Months Ended
	Jun. 30, 2023
Share-Based Payment Arrangement [Abstract]
Equity Transactions and Share-based Compensation	Equity Transactions and Share-based Compensation At-The-Market Equity Offering; Shelf Registration Statement On August 10, 2020, we entered into an Open Market Sale Agreement SM (the Jefferies Sales Agreement) with Jefferies LLC, as agent, pursuant to which we may offer and sell, from time to time through Jefferies, up to $75 million of shares of our common stock. As of June 30, 2023, we have not sold any shares of our common stock under the Jefferies Sales Agreement. On May 6, 2021, we filed an automatic shelf registration statement on Form S-3 with the SEC, which was subsequently amended in March 2022 to convert to a non-automatic shelf registration statement. This registration statement enables us to offer for sale, from time to time, in one or more offerings, up to $250 million in the aggregate, of common stock, debt securities, warrants, rights and/or units, and will remain in effect for up to three years from the date it became effective. As of June 30, 2023, no sales have been made under the shelf registration statement. Stock Options The Company maintains a 2013 Equity Incentive Plan (the 2013 Plan), which provides for the grant of incentive stock options (ISOs), non-statutory stock options (NSOs), stock appreciation rights, restricted stock awards, restricted stock unit (RSU) awards, performance-based stock awards, and other forms of equity compensation (collectively, stock awards), all of which may be granted to employees, including officers, non-employee directors and consultants of the Company and its affiliates. Additionally, the 2013 Plan provides for the grant of performance cash awards. The number of shares of common stock reserved for future issuance automatically increased on January 1, 2023, by 4% of the total number of shares of capital stock outstanding on December 31 of the preceding calendar year, or 3.5 million shares. As of June 30, 2023, there was a total of 2.6 million shares reserved for future issuance under the 2013 Plan. The Company issued no shares of common stock pursuant to the exercise of stock options during the three and six months ended June 30, 2023. The Company issued no shares and approximately 34,000 shares of common stock pursuant to the exercise of stock options during the three and six months ended June 30, 2022. Employee Stock Purchase Plan The Company maintains a 2013 Employee Stock Purchase Plan (ESPP), which provides for the issuance of shares of common stock pursuant to purchase rights granted to the Company’s employees or to employees of any of its designated affiliates. The Company has reserved a total of 4.8 million shares of common stock to be purchased under the ESPP, of which 2.3 million shares remained available for purchase as of June 30, 2023. The number of shares of common stock reserved for issuance automatically increased on January 1, 2023, by an additional 422,535 shares. The ESPP provides for an automatic reset feature to start participants on a new twenty-four month participation period in the event that the common stock market value on a purchase date is less than the common stock value on the first day of the twenty-four month offering period. Eligible employees may authorize an amount up to 15% of their salary to purchase common stock at the lower of a 15% discount to the beginning price of their offering period or a 15% discount to the ending price of each six-month purchase interval. The Company issued approximately 308,000 and 384,000 shares of common stock pursuant to the ESPP during the six months ended June 30, 2023 and 2022, respectively. Compensation expense for shares purchased under the ESPP related to the purchase discount and the “look-back” option and were determined using a Black-Scholes option pricing model. Restricted Stock Units The Company has issued RSUs to certain employees which vest based on service criteria. When vested, the RSU represents the right to be issued the number of shares of the Company’s common stock that is equal to the number of RSUs granted. The grant date fair value for RSUs is based upon the market price of the Company’s common stock on the date of the grant. The fair value is then amortized to compensation expense over the requisite service period or vesting term. The Company issued no shares and approximately 221,000 of common stock pursuant to the vesting of RSUs during the three and six months ended June 30, 2023. The Company issued no shares and approximately 134,000 shares of common stock pursuant to the vesting of RSUs during the three and six months ended June 30, 2022. Stock-based Compensation For awards with only service conditions and graded-vesting features, the Company recognizes compensation expense on a straight-line basis over the requisite service period. Total share-based compensation expense recognized related to stock options, the ESPP and RSUs was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development expense $ 1,566 $ 1,827 $ 3,880 $ 3,730 General and administrative expense 1,393 1,766 3,444 3,571 Total share-based compensation expense $ 2,959 $ 3,593 $ 7,324 $ 7,301 In December 2022, the Company announced a reduction in workforce. As a result, certain vested stock options were modified to extend their exercise period from 90 days to 12 months. In addition, certain outstanding stock option and RSU grants received accelerated vesting as if the service period of the terminated employee continued for up to an additional 12-month period. The Company recorded expense ratably from the announcement date through the date of termination with approximately $0.4 million being recognized during the twelve months ended December 31, 2022 and an additional $0.6 million being recognized during the three months ended March, 31, 2023. In January 2023, the Company extended the post-termination exercise period from 90 days to three years for stock option grants made to non-employee members of our Board of Directors. This extension applies to all future grants as well as all then-outstanding grants. Related to this extension, the Company recorded approximately $0.3 million of expense during the three months ended March 31, 2023.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company estimates an annual effective tax rate of 0.0% for the year ending December 31, 2023 as the Company incurred losses for the six month period ended June 30, 2023 and is forecasting an estimated net loss for both financial statement and tax purposes for the year ending December 31, 2023. Therefore, no federal or state income taxes are expected and none have been recorded at this time. Income taxes have been accounted for using the liability method in accordance with FASB ASC 740. Due to the Company's history of losses since inception, there is not enough evidence at this time to support that the Company will generate future income of a sufficient amount and nature to utilize the benefits of its net deferred tax assets. Accordingly, the deferred tax assets have been reduced by a full valuation allowance, since the Company cannot currently support that realization of its deferred tax assets is more likely than not. However, the Company feels its deferred tax assets may be used upon the Company becoming profitable. At June 30, 2023, the Company had no unrecognized tax benefits that would reduce the Company’s effective tax rate if recognized.

Significant Agreements

Significant Agreements	6 Months Ended
	Jun. 30, 2023
Revenue Recognition [Abstract]
Significant Agreements	Significant Agreements BARDA 2022 Procurement and Development Contract On August 26, 2022, the Company entered into a procurement contract (as amended, the BARDA Agreement) with BARDA for the delivery of up to 1.7 million treatment courses of tablet and suspension formulations of TEMBEXA® to the U.S. government over a possible 10-year period. The BARDA Agreement consists of a five-year base period of performance and a total contract period of performance (base period plus option exercises) of up to ten years (if necessary). Under the terms of the BARDA Agreement, the base period activities are valued at approximately $127 million, consisting of an initial shipment of 319,000 treatment courses of TEMBEXA for delivery to the Strategic National Stockpile for an aggregate purchase price of approximately $115 million, and reimbursement for certain post-marketing activities of approximately $12 million. The options under the BARDA Agreement, which are exercised at the sole discretion of BARDA, are valued at approximately $553 million (if all such options are exercised during the 10-year contract period), which consists of options to purchase up to an additional 1.381 million treatment courses of TEMBEXA for an aggregate purchase price of approximately $551 million and funding for certain post-marketing activities of approximately $2 million. In connection with the sale of the TEMBEXA assets to Emergent, the BARDA Agreement was novated to Emergent in December 2022. In accordance with federal regulations, the terms of the novation agreement require that the Company guarantee the performance of all obligations transferred to Emergent should Emergent not have the ability to deliver on the terms of the BARDA Agreement. In this instance, BARDA may request that we perform the obligations in place of Emergent. Emergent BioSolutions, Inc. On September 26, 2022, the Company completed the Asset Sale to Emergent of the Company’s exclusive worldwide rights to brincidofovir, including TEMBEXA and specified related assets (the Asset Sale). Emergent paid the Company an upfront cash payment of approximately $238 million upon the closing of the Asset Sale. In addition, pursuant to the Asset Purchase Agreement, the Company is eligible to receive from Emergent: (i) up to an aggregate of approximately $124 million in milestone payments payable upon the exercise of the options under the BARDA Agreement for the delivery of up to 1.7 million treatment courses of tablet and suspension formulations of TEMBEXA to the U.S. government; (ii) royalty payments equal to 15% of the gross profits from the sales of TEMBEXA made outside of the United States; (iii) royalty payments equal to 20% of the gross profits from the sales of TEMBEXA made in the United States in excess of 1.7 million treatment courses; and (iv) up to an additional $12.5 million upon the achievement of certain other developmental milestones. The effects of recording certain adjustments associated with contingent consideration related to TEMBEXA have been excluded as the Company has made a policy election to account for these amounts when the contingency has been resolved in accordance with Accounting Standards Codification 450, Contingencies . The period under which the Company was contracted to provide the majority of operational support services to Emergent in furtherance of its obligations under the Asset Purchase Agreement and the BARDA Agreement concluded on March 26, 2023, except for certain services which the parties agreed would continue until the occurrence of a specific event, or in some cases a predetermined end date. The BARDA Agreement was novated to Emergent in December 2022. Under the Asset Purchase Agreement, the Company recognized approximately $26,000 and $0.2 million of contract revenue for support provided for the three and six months ended June 30, 2023, respectively. The sale of TEMBEXA constitutes a significant disposition of a business, however, the Company determined the disposition did not represent a strategic shift, and accordingly, the Company did not account for the disposition as a discontinued operation. The Company recorded a $229.7 million net gain on sale of business in other income (loss) on the Consolidated Statement of Operations and Comprehensive Income (Loss) in the third quarter of 2022. The net gain consists of the following assets and liabilities transferred in accordance with the Asset Purchase Agreement (in thousands): As of September 26, 2022 Up-front cash payment $ 237,987 Liabilities assumed by Emergent 1,423 Inventory transferred to Emergent (5,227) Prepaids transferred to Emergent (511) Transaction costs incurred (4,002) Net gain $ 229,670 TEMBEXA Procurement Agreements In June 2022, the Company entered into a Supply Agreement (the Supply Agreement) with a third-party outside of North America (the Purchaser), pursuant to which the Company was responsible for supplying to the Purchaser, and the Purchaser was responsible for purchasing from the Company, TEMBEXA treatment courses for use in a jurisdiction outside of the United States. Under the terms of the Supply Agreement, the Purchaser paid the Company an aggregate purchase price of approximately $9.3 million, in two equal installments in June and July 2022. The Company recognized $9.3 million of procurement revenue under the Supply Agreement for the three months ended September 30, 2022. Additionally, in June 2022, the Public Health Agency of Canada (PHAC) awarded a Contract (PHAC Contract) to the Company, pursuant to which PHAC agreed to purchase up to approximately USD $25.3 million (CAD $33.0 million) of TEMBEXA treatment courses for use in Canada. Substantially all of the procurement was delivered and accepted by PHAC in July 2022, completing the performance obligation for those shipments and resulting in $22.6 million of procurement revenue for the three months ended September 2022. Upon the assignment of the PHAC Contract to Emergent, which requires the consent of PHAC, if the remaining deliveries of treatment courses are made by Emergent, they will be subject to the royalty terms of the Asset Purchase Agreement applicable to gross profits outside the United States. PHAC assigned the PHAC Contract to Emergent in November 2022. The remaining deliveries of treatment courses were delivered by Emergent and are subject to the royalty terms of the Asset Purchase Agreement applicable to gross profits outside the United States. The Company recognized approximately $0.4 million of royalty revenue in the three months ended December 31, 2022. Ohara Agreement In 2019, Oncoceutics, Inc., a Delaware corporation (Oncoceutics) which was subsequently acquired by the Company in January 2021, entered into a license, development and commercialization agreement with Ohara Pharmaceutical Co., Ltd. for ONC201 in Japan. The Company is entitled to receive up to $2.5 million in nonrefundable regulatory milestone payments. The Company is entitled to double-digit tiered royalties based on the aggregate annual net sales of all products, as defined in the agreement, in Japan. CR Sanjiu Agreement In December 2020, Oncoceutics entered into a license, development and commercialization agreement with China Resources Sanjiu Medical & Pharmaceutical Co., Ltd. (CR Sanjiu). Oncoceutics granted CR Sanjiu an exclusive royalty bearing license to develop and commercialize ONC201 in China, Hong Kong, Macau and Taiwan (CR Sanjiu Territory). The Company is entitled to receive up to $5.0 million in nonrefundable regulatory milestone payments. The Company is entitled to double-digit tiered royalties based on the aggregate annual net sales of all licensed products, as defined in the agreement, in the CR Sanjiu Territory. Note 7. DSTAT Contract Close-out In May 2022, the Company made the decision to discontinue the development of DSTAT for the treatment of AML. Effective July 12, 2022, the Company terminated the License and Development Agreement with Cantex. As a result, the Company recorded an accrual of expenses to close-out the DSTAT vendor contracts. As of June 30, 2023, on the Consolidated Balance Sheets, the Company has recorded $0.9 million of contract close-out costs in accrued liabilities and accounts payable. These balances are expected to be fully paid prior to the end of 2023. The following table summarizes the contract close-out costs (in thousands) recorded in 2022: Contract Close-out Costs Research & development $ 791 General & administrative 8 Total contract close-out expenses $ 799 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for 2022. Contract Close-out Costs Balance at June 30, 2022 $ 4,539 Revised estimates (746) Payments (2,482) Balance at December 31, 2022 $ 1,311 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for the six months ended June 30, 2023. Contract Close-out Costs Balance at December 31, 2022 $ 1,311 Revised estimates 10 Payments (250) Balance at March 31, 2023 $ 1,071 Revised estimates (122) Payments (96) Balance at June 30, 2023 $ 853

DSTAT Contract Close-out

DSTAT Contract Close-out	6 Months Ended
	Jun. 30, 2023
Revenue Recognition [Abstract]
DSTAT Contract Close-out	Significant Agreements BARDA 2022 Procurement and Development Contract On August 26, 2022, the Company entered into a procurement contract (as amended, the BARDA Agreement) with BARDA for the delivery of up to 1.7 million treatment courses of tablet and suspension formulations of TEMBEXA® to the U.S. government over a possible 10-year period. The BARDA Agreement consists of a five-year base period of performance and a total contract period of performance (base period plus option exercises) of up to ten years (if necessary). Under the terms of the BARDA Agreement, the base period activities are valued at approximately $127 million, consisting of an initial shipment of 319,000 treatment courses of TEMBEXA for delivery to the Strategic National Stockpile for an aggregate purchase price of approximately $115 million, and reimbursement for certain post-marketing activities of approximately $12 million. The options under the BARDA Agreement, which are exercised at the sole discretion of BARDA, are valued at approximately $553 million (if all such options are exercised during the 10-year contract period), which consists of options to purchase up to an additional 1.381 million treatment courses of TEMBEXA for an aggregate purchase price of approximately $551 million and funding for certain post-marketing activities of approximately $2 million. In connection with the sale of the TEMBEXA assets to Emergent, the BARDA Agreement was novated to Emergent in December 2022. In accordance with federal regulations, the terms of the novation agreement require that the Company guarantee the performance of all obligations transferred to Emergent should Emergent not have the ability to deliver on the terms of the BARDA Agreement. In this instance, BARDA may request that we perform the obligations in place of Emergent. Emergent BioSolutions, Inc. On September 26, 2022, the Company completed the Asset Sale to Emergent of the Company’s exclusive worldwide rights to brincidofovir, including TEMBEXA and specified related assets (the Asset Sale). Emergent paid the Company an upfront cash payment of approximately $238 million upon the closing of the Asset Sale. In addition, pursuant to the Asset Purchase Agreement, the Company is eligible to receive from Emergent: (i) up to an aggregate of approximately $124 million in milestone payments payable upon the exercise of the options under the BARDA Agreement for the delivery of up to 1.7 million treatment courses of tablet and suspension formulations of TEMBEXA to the U.S. government; (ii) royalty payments equal to 15% of the gross profits from the sales of TEMBEXA made outside of the United States; (iii) royalty payments equal to 20% of the gross profits from the sales of TEMBEXA made in the United States in excess of 1.7 million treatment courses; and (iv) up to an additional $12.5 million upon the achievement of certain other developmental milestones. The effects of recording certain adjustments associated with contingent consideration related to TEMBEXA have been excluded as the Company has made a policy election to account for these amounts when the contingency has been resolved in accordance with Accounting Standards Codification 450, Contingencies . The period under which the Company was contracted to provide the majority of operational support services to Emergent in furtherance of its obligations under the Asset Purchase Agreement and the BARDA Agreement concluded on March 26, 2023, except for certain services which the parties agreed would continue until the occurrence of a specific event, or in some cases a predetermined end date. The BARDA Agreement was novated to Emergent in December 2022. Under the Asset Purchase Agreement, the Company recognized approximately $26,000 and $0.2 million of contract revenue for support provided for the three and six months ended June 30, 2023, respectively. The sale of TEMBEXA constitutes a significant disposition of a business, however, the Company determined the disposition did not represent a strategic shift, and accordingly, the Company did not account for the disposition as a discontinued operation. The Company recorded a $229.7 million net gain on sale of business in other income (loss) on the Consolidated Statement of Operations and Comprehensive Income (Loss) in the third quarter of 2022. The net gain consists of the following assets and liabilities transferred in accordance with the Asset Purchase Agreement (in thousands): As of September 26, 2022 Up-front cash payment $ 237,987 Liabilities assumed by Emergent 1,423 Inventory transferred to Emergent (5,227) Prepaids transferred to Emergent (511) Transaction costs incurred (4,002) Net gain $ 229,670 TEMBEXA Procurement Agreements In June 2022, the Company entered into a Supply Agreement (the Supply Agreement) with a third-party outside of North America (the Purchaser), pursuant to which the Company was responsible for supplying to the Purchaser, and the Purchaser was responsible for purchasing from the Company, TEMBEXA treatment courses for use in a jurisdiction outside of the United States. Under the terms of the Supply Agreement, the Purchaser paid the Company an aggregate purchase price of approximately $9.3 million, in two equal installments in June and July 2022. The Company recognized $9.3 million of procurement revenue under the Supply Agreement for the three months ended September 30, 2022. Additionally, in June 2022, the Public Health Agency of Canada (PHAC) awarded a Contract (PHAC Contract) to the Company, pursuant to which PHAC agreed to purchase up to approximately USD $25.3 million (CAD $33.0 million) of TEMBEXA treatment courses for use in Canada. Substantially all of the procurement was delivered and accepted by PHAC in July 2022, completing the performance obligation for those shipments and resulting in $22.6 million of procurement revenue for the three months ended September 2022. Upon the assignment of the PHAC Contract to Emergent, which requires the consent of PHAC, if the remaining deliveries of treatment courses are made by Emergent, they will be subject to the royalty terms of the Asset Purchase Agreement applicable to gross profits outside the United States. PHAC assigned the PHAC Contract to Emergent in November 2022. The remaining deliveries of treatment courses were delivered by Emergent and are subject to the royalty terms of the Asset Purchase Agreement applicable to gross profits outside the United States. The Company recognized approximately $0.4 million of royalty revenue in the three months ended December 31, 2022. Ohara Agreement In 2019, Oncoceutics, Inc., a Delaware corporation (Oncoceutics) which was subsequently acquired by the Company in January 2021, entered into a license, development and commercialization agreement with Ohara Pharmaceutical Co., Ltd. for ONC201 in Japan. The Company is entitled to receive up to $2.5 million in nonrefundable regulatory milestone payments. The Company is entitled to double-digit tiered royalties based on the aggregate annual net sales of all products, as defined in the agreement, in Japan. CR Sanjiu Agreement In December 2020, Oncoceutics entered into a license, development and commercialization agreement with China Resources Sanjiu Medical & Pharmaceutical Co., Ltd. (CR Sanjiu). Oncoceutics granted CR Sanjiu an exclusive royalty bearing license to develop and commercialize ONC201 in China, Hong Kong, Macau and Taiwan (CR Sanjiu Territory). The Company is entitled to receive up to $5.0 million in nonrefundable regulatory milestone payments. The Company is entitled to double-digit tiered royalties based on the aggregate annual net sales of all licensed products, as defined in the agreement, in the CR Sanjiu Territory. Note 7. DSTAT Contract Close-out In May 2022, the Company made the decision to discontinue the development of DSTAT for the treatment of AML. Effective July 12, 2022, the Company terminated the License and Development Agreement with Cantex. As a result, the Company recorded an accrual of expenses to close-out the DSTAT vendor contracts. As of June 30, 2023, on the Consolidated Balance Sheets, the Company has recorded $0.9 million of contract close-out costs in accrued liabilities and accounts payable. These balances are expected to be fully paid prior to the end of 2023. The following table summarizes the contract close-out costs (in thousands) recorded in 2022: Contract Close-out Costs Research & development $ 791 General & administrative 8 Total contract close-out expenses $ 799 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for 2022. Contract Close-out Costs Balance at June 30, 2022 $ 4,539 Revised estimates (746) Payments (2,482) Balance at December 31, 2022 $ 1,311 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for the six months ended June 30, 2023. Contract Close-out Costs Balance at December 31, 2022 $ 1,311 Revised estimates 10 Payments (250) Balance at March 31, 2023 $ 1,071 Revised estimates (122) Payments (96) Balance at June 30, 2023 $ 853

Restructuring Costs

Restructuring Costs	6 Months Ended
	Jun. 30, 2023
Restructuring and Related Activities [Abstract]
Restructuring Costs	Restructuring Costs In December 2022, the Company made the decision to restructure its operations, which included a reduction in workforce of 20 full-time employees. During the three months ended December 31, 2022, the Company recorded expense for one-time employee termination benefits of $1.9 million, which included a ratable share of the total stock compensation expense that resulted from the modifications of stock option agreements of employees. The total amount of stock compensation expense related to the reduction in workforce equals $1.0 million of which $0.4 million was recorded in the fourth quarter of 2022. The following table summarizes the restructuring charges (in thousands) recorded for the three months ended December 31, 2022: Employee Termination Benefits Research and development $ 1,768 General and administrative 86 Total restructuring expenses $ 1,854 The following table sets forth the accrual activity for employee termination benefits (in thousands) for the six months ended June 30, 2023: Employee Termination Benefits Balance at December 31, 2022 $ 1,442 Revised estimates (73) Payments (641) Balance at March 31, 2023 $ 728 Revised estimates (89) Payments (395) Balance at June 30, 2023 $ 244

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsThe Company has evaluated subsequent events through the issuance date of these financial statements to ensure that this filing includes appropriate disclosure of events both recognized in the financial statements as of June 30, 2023, and events which occurred subsequently but were not recognized in the financial statements.

The Business and Summary of S_2

The Business and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of PresentationThe accompanying unaudited consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Company’s audited financial statements and notes thereto included in its Annual Report on Form 10-K for the year ended December 31, 2022. In the opinion of the Company’s management, all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of its financial position, operating results and cash flows for the periods presented have been included. Operating results for the three and six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the full year, for any other interim period or for any future year.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts of certain financial instruments, including accounts receivable, accounts payable and accrued expenses approximate their fair values due to the short-term nature of such instruments. For assets and liabilities recorded at fair value, it is the Company’s policy to maximize the use of observable inputs and minimize the use of unobservable inputs when developing fair value measurements, in accordance with the fair value hierarchy. Fair value measurements for assets and liabilities where there exists limited or no observable market data are based primarily upon estimates and are often calculated based on the economic and competitive environment, the characteristics of the asset or liability and other factors. Therefore, fair value measurements cannot be determined with precision and may not be realized in an actual sale or immediate settlement of the asset or liability. Additionally, there may be inherent weaknesses in any calculation technique and changes in the underlying assumptions used, including discount rates and estimates of future cash flows, could significantly affect the calculated current or future fair values. The Company utilizes fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. The Company groups assets and liabilities at fair value in three levels, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. The determination of where an asset or liability falls in the hierarchy requires significant judgment. These levels are: • Level 1 — Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access. • Level 2 — Valuations based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and models for which all significant inputs are observable, either directly or indirectly. • Level 3 — Valuations based on inputs that are unobservable and significant to the overall fair value measurement. There was no material re-measurement to fair value of financial assets and liabilities that are not measured at fair value on a recurring basis. For additional information regarding the Company’s investments, please refer to Note 2, “Investments.”
Inventories	Inventories The Company considers regulatory approval of product candidates to be uncertain and product manufactured prior to regulatory approval may not be sold unless regulatory approval is obtained. As such, the manufacturing costs for product candidates incurred prior to regulatory approval are not capitalized as inventory but are expensed as research and development costs. The Company begins capitalization of these inventory related costs once regulatory approval is obtained. The Company primarily uses actual costs to determine its cost basis for inventories. On May 15, 2022, we entered into an Asset Purchase Agreement (the Asset Purchase Agreement) with an affiliate of Emergent BioSolutions Inc. (Emergent BioSolutions) for the sale of our exclusive worldwide rights to brincidofovir, including TEMBEXA® and specified related assets (the Asset Sale). On September 26, 2022, we closed the Asset Sale with Emergent Biodefense Operations Lansing LLC (Emergent), an affiliate of Emergent BioSolutions. Prior to the sale of TEMBEXA to Emergent, the Company’s inventory consisted of TEMBEXA, which was being manufactured for the treatment of smallpox for potential delivery to the Strategic National Stockpile (SNS) for the U.S. government and to other government agencies. TEMBEXA was approved by the FDA on June 4, 2021, at which time the Company began to capitalize inventory costs associated with TEMBEXA. Prior to FDA approval of TEMBEXA, all costs related to the manufacturing of TEMBEXA were charged to research and development expense in the period incurred as there was no alternative future use. The Company valued its inventories at the lower of cost or estimated net realizable value. The Company determined the cost of its inventories, which included amounts related to materials, manufacturing costs, shipping and handling costs on a first-in, first-out (FIFO) basis. Work-in-process included all inventory costs prior to packaging and labelling, including raw material, active product ingredient, and drug product. Finished goods included packaged and labelled products. Title to all inventory was transferred to Emergent upon the close of the Asset Sale.
Revenue Recognition	Revenue Recognition Policy The Company’s revenues generally consist of (i) contract and grant revenue—revenue generated under federal and private foundation grants and contracts, (ii) licensing revenue—revenue related to non-refundable upfront fees, royalties and milestone payments earned under license agreements (iii) royalty revenue—revenue related to sales of TEMBEXA made by Emergent after the Asset Sale, and (iv) procurement revenue—revenue related to sales of TEMBEXA prior to the Asset Sale. Revenue is recognized in accordance with the criteria outlined in Accounting Standards Codification (ASC) 606 issued by the Financial Accounting Standards Board (FASB). Following this accounting pronouncement, a five-step approach is applied for recognizing revenue, including (1) identify the contract with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when, or as, the entity satisfies a performance obligation.
Research and Development Prepaids and Accruals	Research and Development Prepaids and Accruals As part of the process of preparing financial statements, the Company is required to estimate its expenses resulting from its obligation under contracts with vendors and consultants and clinical site agreements in connection with its research and development efforts. The financial terms of these contracts are subject to negotiations which vary contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to the Company under such contracts. The Company’s objective is to reflect the appropriate research and development expenses in its financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of its research and development efforts. The Company determines prepaid and accrual estimates through discussion with applicable personnel and outside service providers as to the progress or state of communication of clinical trials, or other services completed. The Company adjusts its rate of research and development expense recognition if actual results differ from its estimates. The Company makes estimates of its prepaid and accrued expenses as of each balance sheet date in its financial statements based on facts and circumstances known at that time. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of status and timing of services performed relative to the actual status and timing of services performed may vary and may result in the Company reporting amounts that are too high or too low for any particular period. Through June 30, 2023, there had been no material adjustments to the Company’s prior period estimates of prepaid and accruals for research and development expenses. The Company’s research and development prepaids and accruals are dependent upon the timely and accurate reporting of contract research organizations and other third-party vendors.
Basic and Diluted Net Income (Loss) Per Share of Common Stock	Basic and Diluted Net Income (Loss) Per Share of Common Stock Basic net income (loss) per share of common stock is computed by dividing net income (loss) by the weighted-average number of shares of common stock outstanding during the period, excluding the dilutive effects of non-vested restricted stock, stock options, and employee stock purchase plan purchase rights. Diluted net income (loss) per share of common stock is computed by dividing net income (loss) by the sum of the weighted-average number of shares of common stock outstanding during the period plus the potential dilutive effects of non-vested restricted stock, stock options, and employee stock purchase plan purchase rights outstanding during the period calculated in accordance with the treasury stock method, but are excluded if their effect is anti-dilutive. Because the impact of these items is anti-dilutive during the periods of net loss, there was no difference between basic and diluted loss per share of common stock for the three and six months ended June 30, 2023 and 2022.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. In addition to estimates discussed in other sections of this Quarterly Report on Form 10-Q, the most significant estimates in the Company’s consolidated financial statements relate to the valuation of stock options and the valuation allowance for deferred tax assets resulting from net operating losses. These estimates are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates.
Segments	SegmentsThe Company operates in only one segment, pharmaceuticals.
Impact of Recently Adopted Accounting Standards	Impact of Recently Adopted Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which amends the impairment model by requiring entities to use a forward-looking approach on expected losses to estimate credit losses on certain financial instruments, including trade receivables and available-for-sale debt securities. The new guidance was originally due to become effective for the Company beginning in the first quarter of 2020, however the FASB in November 2019 issued ASU 2019-10 which moved the effective date for smaller reporting companies to the first quarter of 2023. The Company adopted ASU 2016-03 as of January 1, 2023. Given the nature of the Company’s receivables and investment portfolio, adoption of this standard had no impact on the Company's financial position, results of operations or cash flows.

The Business and Summary of S_3

The Business and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Schedule of Certain Assets Measured at Fair Value on a Recurring Basis	Below are tables that present information about certain assets measured at fair value on a recurring basis (in thousands): Fair Value Measurements June 30, 2023 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 18,142 $ 18,142 $ — $ — Total cash equivalents 18,142 18,142 — — Short-term investments U.S. treasury securities 82,033 37,496 44,537 — Commercial paper 76,124 — 76,124 — Corporate bonds 27,500 — 27,500 — Total short-term investments 185,657 37,496 148,161 — Long-term investments U.S. treasury securities 27,258 2,924 24,334 — Total long-term investments 27,258 2,924 24,334 — Total assets $ 231,057 $ 58,562 $ 172,495 $ — Fair Value Measurements December 31, 2022 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 17,826 $ 17,826 $ — $ — Commercial paper 4,998 — 4,998 — Total cash equivalents 22,824 17,826 4,998 — Short-term investments U.S. treasury securities 38,094 25,271 12,823 — Commercial paper 127,517 — 127,517 — Corporate bonds 25,881 — 25,881 — Total short-term investments 191,492 25,271 166,221 — Long-term investments U.S. treasury securities 48,626 11,685 36,941 — Total long-term investments 48,626 11,685 36,941 — Total assets $ 262,942 $ 54,782 $ 208,160 $ —
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): June 30, 2023 December 31, 2022 Accrued research and development expenses $ 7,591 $ 6,691 Accrued compensation 3,649 6,438 Other accrued liabilities 2,278 4,252 Total accrued liabilities $ 13,518 $ 17,381

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Schedule of Short-Term and Long-Term Investments	The following tables summarize the Company’s debt investments (in thousands): June 30, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 27,556 $ — $ (56) $ 27,500 Commercial paper 76,211 3 (90) 76,124 U.S. treasury securities 109,961 1 (671) 109,291 Total investments $ 213,728 $ 4 $ (817) $ 212,915 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 25,906 $ 4 $ (29) $ 25,881 Commercial paper 127,657 36 (176) 127,517 U.S. treasury securities 86,892 7 (179) 86,720 Total investments $ 240,455 $ 47 $ (384) $ 240,118
Schedule of Investments with Unrealized Losses, Aggregated by Investment Type and the Length of Time	The following tables summarize the Company’s debt investments with unrealized losses, aggregated by investment type and the length of time that individual investments have been in a continuous unrealized loss position (in thousands, except number of securities): June 30, 2023 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 27,500 $ (56) $ — $ — $ 27,500 $ (56) Commercial paper 55,662 (90) — — 55,662 (90) U.S. treasury securities 104,558 (672) — — 104,558 (672) Total $ 187,720 $ (818) $ — $ — $ 187,720 $ (818) Number of securities with unrealized losses 60 — 60 December 31, 2022 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 22,905 $ (29) $ — $ — $ 22,905 $ (29) Commercial paper 88,860 (176) — — 88,860 (176) U.S. treasury securities $ 67,489 $ (179) $ — $ — $ 67,489 $ (179) Total $ 179,254 $ (384) $ — $ — $ 179,254 $ (384) Number of securities with unrealized losses 55 — 55
Schedule of the Scheduled Maturity of Company Investments	The following table summarizes the scheduled maturity for the Company’s debt investments at June 30, 2023 (in thousands): Maturing in one year or less $ 185,657 Maturing after one year through two years 27,258 Total debt investments $ 212,915

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Operating Lease Right-of-Use Assets and Liabilities	The following table sets forth the operating lease right-of-use assets and liabilities as of June 30, 2023 (in thousands): Assets Operating lease right-of-use assets $ 1,728 Liabilities Operating lease short-term liabilities (recorded within Accrued liabilities) $ 607 Operating lease long-term liabilities (recorded within Lease-related obligations) 1,507 Total operating lease liabilities $ 2,114
Schedule of Operating Lease Maturity	Operating lease payments over the remainder of the lease terms are as follows (in thousands): Years Ending December 31, As of June 30, 2023 2023 371 2024 759 2025 781 2026 467 Total future minimum rental payments $ 2,378 Less amount of lease payments representing interest 264 Total present value of lease payments $ 2,114 As of December 31, 2022, operating lease payments over the remainder of the lease terms were as follows (in thousands): Years Ending December 31, As of December 31, 2022 2023 736 2024 759 2025 781 2026 467 Total future minimum rental payments $ 2,743 Less amount of lease payments representing interest 351 Total present value of lease payments $ 2,392

Equity Transactions and Share_2

Equity Transactions and Share-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Employee and Non-Employee Share-Based Compensation Expense Recognized Related to Stock Options, the ESPP and RSUs	Total share-based compensation expense recognized related to stock options, the ESPP and RSUs was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development expense $ 1,566 $ 1,827 $ 3,880 $ 3,730 General and administrative expense 1,393 1,766 3,444 3,571 Total share-based compensation expense $ 2,959 $ 3,593 $ 7,324 $ 7,301

Significant Agreements (Tables)

Significant Agreements (Tables)	6 Months Ended
	Jun. 30, 2023
Revenue Recognition [Abstract]
Schedule Of Net Gain From The Sales Of Assets	The net gain consists of the following assets and liabilities transferred in accordance with the Asset Purchase Agreement (in thousands): As of September 26, 2022 Up-front cash payment $ 237,987 Liabilities assumed by Emergent 1,423 Inventory transferred to Emergent (5,227) Prepaids transferred to Emergent (511) Transaction costs incurred (4,002) Net gain $ 229,670

DSTAT Contract Close-out (Table

DSTAT Contract Close-out (Tables)	6 Months Ended
	Jun. 30, 2023
Revenue Recognition [Abstract]
Schedule of Accrual Activities for Contract Close-out Cost	The following table summarizes the contract close-out costs (in thousands) recorded in 2022: Contract Close-out Costs Research & development $ 791 General & administrative 8 Total contract close-out expenses $ 799 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for 2022. Contract Close-out Costs Balance at June 30, 2022 $ 4,539 Revised estimates (746) Payments (2,482) Balance at December 31, 2022 $ 1,311 The following table sets forth the accounts payable and accrual activity for contract close-out costs (in thousands) for the six months ended June 30, 2023. Contract Close-out Costs Balance at December 31, 2022 $ 1,311 Revised estimates 10 Payments (250) Balance at March 31, 2023 $ 1,071 Revised estimates (122) Payments (96) Balance at June 30, 2023 $ 853

Restructuring Costs (Tables)

Restructuring Costs (Tables)	6 Months Ended
	Jun. 30, 2023
Restructuring and Related Activities [Abstract]
Schedule of Restructuring and Related Costs	The following table summarizes the restructuring charges (in thousands) recorded for the three months ended December 31, 2022: Employee Termination Benefits Research and development $ 1,768 General and administrative 86 Total restructuring expenses $ 1,854
Schedule of Restructuring Reserve by Type of Cost	The following table sets forth the accrual activity for employee termination benefits (in thousands) for the six months ended June 30, 2023: Employee Termination Benefits Balance at December 31, 2022 $ 1,442 Revised estimates (73) Payments (641) Balance at March 31, 2023 $ 728 Revised estimates (89) Payments (395) Balance at June 30, 2023 $ 244

The Business and Summary of S_4

The Business and Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Separate Account Investment
Short-term investments	$ 185,657	$ 191,492
Total long-term investments	27,258	48,626
Fair value, measurements, recurring
Fair Value, Separate Account Investment
Cash equivalents	18,142	22,824
Short-term investments	185,657	191,492
Total long-term investments	27,258	48,626
Total assets	231,057	262,942
Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Cash equivalents	18,142	17,826
Short-term investments	37,496	25,271
Total long-term investments	2,924	11,685
Total assets	58,562	54,782
Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Cash equivalents	0	4,998
Short-term investments	148,161	166,221
Total long-term investments	24,334	36,941
Total assets	172,495	208,160
Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Cash equivalents	0	0
Short-term investments	0	0
Total long-term investments	0	0
Total assets	0	0
U.S. treasury securities | Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments	82,033	38,094
Total long-term investments	27,258	48,626
U.S. treasury securities | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments	37,496	25,271
Total long-term investments	2,924	11,685
U.S. treasury securities | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments	44,537	12,823
Total long-term investments	24,334	36,941
U.S. treasury securities | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments	0	0
Total long-term investments	0	0
Commercial paper | Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments	76,124	127,517
Commercial paper | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments	0	0
Commercial paper | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments	76,124	127,517
Commercial paper | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments	0	0
Corporate bonds | Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments	27,500	25,881
Corporate bonds | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments	0	0
Corporate bonds | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments	27,500	25,881
Corporate bonds | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments	0	0
Money Market Funds [Member] | Fair value, measurements, recurring
Fair Value, Separate Account Investment
Cash equivalents	18,142	17,826
Money Market Funds [Member] | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Cash equivalents	18,142	17,826
Money Market Funds [Member] | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Cash equivalents	0	0
Money Market Funds [Member] | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Cash equivalents	$ 0	0
Commercial paper | Fair value, measurements, recurring
Fair Value, Separate Account Investment
Cash equivalents		4,998
Commercial paper | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Cash equivalents		0
Commercial paper | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Cash equivalents		4,998
Commercial paper | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Cash equivalents		$ 0

The Business and Summary of S_5

The Business and Summary of Significant Accounting Policies - Employee Retention Credit (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Business and Summary of Significant Accounting Policies
Employee retention credit		$ 2,000
Research and development	$ 16,926		$ 18,047	$ 35,748	$ 37,087
General and administrative	$ 4,448		$ 5,840	10,127	$ 11,472
Proceeds from tax refund				$ 27
Scenario, Adjustment
Business and Summary of Significant Accounting Policies
Research and development		(1,500)
General and administrative		$ (500)

The Business and Summary of S_6

The Business and Summary of Significant Accounting Policies - Deferred Loan Costs (Details)	Jan. 31, 2022 USD ($) installment	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Business and Summary of Significant Accounting Policies
Non-current loan fee liability		$ 125,000	$ 250,000
Revolving Credit Facility
Business and Summary of Significant Accounting Policies
Debt instrument, term (in years)	4 years
Aggregate principal amount	$ 50,000,000
Debt instrument, interest rate, stated (as a percent)	4.75%
Line of credit facility, unused capacity, commitment fee (as a percent)	0.25%
Debt instrument, early termination fee	$ 500,000
Debt instrument, unused borrowing capacity, fee	$ 500,000
Number of installment payments (installment) | installment	4
Current deferred loan costs		100,000
Noncurrent deferred loan costs		200,000
Loan fee liability		200,000
Non-current loan fee liability		$ 100,000
Revolving Credit Facility | Prime Rate
Business and Summary of Significant Accounting Policies
Debt instrument, basis spread on variable rate (as a percent)	1.50%

The Business and Summary of S_7

The Business and Summary of Significant Accounting Policies - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Accrued research and development expenses	$ 7,591	$ 6,691
Accrued compensation	3,649	6,438
Other accrued liabilities	2,278	4,252
Total accrued liabilities	$ 13,518	$ 17,381

The Business and Summary of S_8

The Business and Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands		1 Months Ended	3 Months Ended				6 Months Ended
	Sep. 26, 2022 USD ($) treatment	Jul. 31, 2022 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) segment	Jun. 30, 2022 USD ($)	Dec. 31, 2019 USD ($)
Business and Summary of Significant Accounting Policies
Contract and grant revenue			$ 26			$ 440	$ 309	$ 455
Number of segment | segment							1
TEMBEXA | PHAC
Business and Summary of Significant Accounting Policies
Contract and grant revenue		$ 22,600			$ 32,000
Grant | Oncoceutics, Inc.
Business and Summary of Significant Accounting Policies
Deferred revenue			100				$ 100
Contract and grant revenue			0			0	30	0
Licensing
Business and Summary of Significant Accounting Policies
Contract and grant revenue			0			440	49	455
Royalty
Business and Summary of Significant Accounting Policies
Contract and grant revenue				$ 400
Emergent
Business and Summary of Significant Accounting Policies
Up-front cash payment	$ 237,987
SymBio Pharmaceuticals | Scenario, Plan
Business and Summary of Significant Accounting Policies
Deferred revenue	12,500
Emergent Biodefense Operations Lansing LLC
Business and Summary of Significant Accounting Policies
Revenue recognized			26				200
Ohara Pharmaceutical Co., Ltd.
Business and Summary of Significant Accounting Policies
License agreement, nonrefundable regulatory milestone payment to be received									$ 2,500
Ohara Pharmaceutical Co., Ltd. | Licensing
Business and Summary of Significant Accounting Policies
Contract and grant revenue			$ 0			$ 400	$ 58	$ 400
Base Period | Emergent | TEMBEXA
Business and Summary of Significant Accounting Policies
Up-front cash payment	$ 238,000
Quantity royalty rate, trigger (treatments) | treatment	1,700,000
Base Period | Emergent | TEMBEXA | Non- United States
Business and Summary of Significant Accounting Policies
Gross profit royalty rate (as a percent)	15%
Base Period | Emergent | TEMBEXA | United States
Business and Summary of Significant Accounting Policies
Gross profit royalty rate (as a percent)	20%
Base Period | Emergent | BARDA
Business and Summary of Significant Accounting Policies
Maximum milestone proceeds upon the exercise of options	$ 124,000

Investments - Schedule of Avail

Investments - Schedule of Available-for-Sale securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Investments
Amortized Cost	$ 213,728	$ 240,455
Gross Unrealized Gains	4	47
Gross Unrealized Losses	(817)	(384)
Estimated Fair Value	212,915	240,118
Corporate bonds
Schedule of Investments
Amortized Cost	27,556	25,906
Gross Unrealized Gains	0	4
Gross Unrealized Losses	(56)	(29)
Estimated Fair Value	27,500	25,881
Commercial paper
Schedule of Investments
Amortized Cost	76,211	127,657
Gross Unrealized Gains	3	36
Gross Unrealized Losses	(90)	(176)
Estimated Fair Value	76,124	127,517
U.S. treasury securities
Schedule of Investments
Amortized Cost	109,961	86,892
Gross Unrealized Gains	1	7
Gross Unrealized Losses	(671)	(179)
Estimated Fair Value	$ 109,291	$ 86,720

Investments - Schedule of Inves

Investments - Schedule of Investments with Unrealized Losses, Aggregated by Investment Type and the Length of Time (Details) $ in Thousands	Jun. 30, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Debt Securities, Available-for-sale
Fair value, less than 12 months	$ 187,720	$ 179,254
Unrealized loss, less than 12 months	(818)	(384)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	187,720	179,254
Unrealized loss, total	$ (818)	$ (384)
Number of securities with unrealized losses, less than 12 months | security	60	55
Number of securities with unrealized losses, greater than 12 months | security	0	0
Number of securities with unrealized losses, total | security	60	55
Corporate bonds
Debt Securities, Available-for-sale
Fair value, less than 12 months	$ 27,500	$ 22,905
Unrealized loss, less than 12 months	(56)	(29)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	27,500	22,905
Unrealized loss, total	(56)	(29)
Commercial paper
Debt Securities, Available-for-sale
Fair value, less than 12 months	55,662	88,860
Unrealized loss, less than 12 months	(90)	(176)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	55,662	88,860
Unrealized loss, total	(90)	(176)
U.S. treasury securities
Debt Securities, Available-for-sale
Fair value, less than 12 months	104,558	67,489
Unrealized loss, less than 12 months	(672)	(179)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	104,558	67,489
Unrealized loss, total	$ (672)	$ (179)

Investments - Schedule of Inv_2

Investments - Schedule of Investment Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value
Maturing in one year or less	$ 185,657
Maturing after one year through two years	27,258
Total debt investments	$ 212,915	$ 240,118

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Disaggregation of Revenue
Weighted average remaining lease term (in years)	3 years 1 month 2 days		3 years 1 month 2 days
Rent expense under non-cancelable operating leases	$ 200	$ 100	$ 300	$ 300
Weighted average discount rate (as a percent)	7.89%		7.89%
Lease payments	$ 200	$ 200	$ 400	$ 300
BARDA | Refundable Agreements
Disaggregation of Revenue
Provision for refundable amounts	$ 52		$ 52		$ 52

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Operating Lease Right-of-Use Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets
Operating lease right-of-use assets	$ 1,728	$ 1,964
Liabilities
Operating lease short-term liabilities (recorded within Accrued liabilities)	607
Operating lease long-term liabilities (recorded within Lease-related obligations)	1,507	1,819
Total operating lease liabilities	$ 2,114	$ 2,392
Operating lease, liability, current, statement of financial position [extensible list]	Accrued Liabilities, Current

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Maturity Analysis of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Lessee, Operating Lease, Liability, Payment, Due
Year one	$ 371	$ 736
Year two	759	759
Year three	781	781
Year four	467	467
Total future minimum rental payments	2,378	2,743
Less amount of lease payments representing interest	264	351
Total present value of lease payments	$ 2,114	$ 2,392

Equity Transactions and Share_3

Equity Transactions and Share-based Compensation - Narrative (Details) - USD ($)		3 Months Ended				6 Months Ended		12 Months Ended
	Jan. 01, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Mar. 31, 2022	Aug. 10, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Shares issued for restricted stock units (in shares)		0			0	221,000	134,000
One-time employee termination benefits			$ 600,000	$ 1,854,000				$ 400,000
The 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Evergreen option provision, equity increase (as a percent)	4%
Additional shares authorized (in shares)	3,500,000
Number of shares reserved for future issuance (in shares)		2,600,000				2,600,000
Shares issued pursuant to the exercise of stock options (in shares)		0			0	0	34,000
The 2013 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award
Additional shares authorized (in shares)	422,535
Number of shares reserved for future issuance (in shares)		2,300,000				2,300,000
Number of shares authorized to be granted (in shares)		4,800,000				4,800,000
Participation term (in months)						24 months
Percentage of pay that employee can contribute, maximum (as a percent)		15%				15%
Discounted purchase price from market price, offering date (as a percent)						15%
Discounted purchase price from market price, purchase date (as a percent)						15%
Purchase interval (in months)						6 months
Shares issued pursuant to employee stock purchase plan (in shares)						308,000	384,000
Public Offering
Share-based Compensation Arrangement by Share-based Payment Award
Sale of common stock, amount authorized									$ 250,000,000	$ 75,000,000
Sales of stock, authorization term (in years)									3 years

Equity Transactions and Share_4

Equity Transactions and Share-based Compensation - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Total share-based compensation expense	$ 2,959		$ 3,593	$ 7,324	$ 7,301
Independent Members Of Board
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Total share-based compensation expense		$ 300
Research and development expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Total share-based compensation expense	1,566		1,827	3,880	3,730
General and administrative expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Total share-based compensation expense	$ 1,393		$ 1,766	$ 3,444	$ 3,571

Income Taxes (Details)

Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Jun. 30, 2023
Income Tax Contingency
Unrecognized tax benefits		$ 0
Scenario, Forecast
Income Tax Contingency
Estimated annual effective tax rate (as a percent)	0%

Significant Agreements- Narrati

Significant Agreements- Narrative (Details) $ in Thousands, $ in Millions

1 Months Ended

3 Months Ended

6 Months Ended

Sep. 26, 2022 USD ($) treatment

Aug. 26, 2022 USD ($) treatment

Jun. 23, 2022 installment

Jul. 31, 2022 USD ($)

Jun. 30, 2023 USD ($)

Dec. 31, 2022 USD ($)

Sep. 30, 2022 USD ($)

Jun. 30, 2022 USD ($)

Jun. 30, 2023 USD ($)

Jun. 30, 2022 USD ($)

Jun. 30, 2022 CAD ($)

Dec. 31, 2020 USD ($)

Dec. 31, 2019 USD ($)

Schedule of Investments

Contract and grant revenue

$ 26

$ 440

$ 309

$ 455

TEMBEXA | Purchaser

Schedule of Investments

Deferred revenue

$ 9,300

Number of payment installments | installment

2

Contract and grant revenue

$ 9,300

TEMBEXA | PHAC

Schedule of Investments

Contract and grant revenue

$ 22,600

32,000

TEMBEXA | Scenario, Plan | Purchaser

Schedule of Investments

Deferred revenue

9,300

9,300

TEMBEXA | Scenario, Plan | PHAC

Schedule of Investments

Deferred revenue

$ 25,300

$ 25,300

$ 33

Royalty

Schedule of Investments

Contract and grant revenue

$ 400

BARDA | TEMBEXA

Schedule of Investments

Base performance, contract term (in years)

5 years

Amount of additional courses at the discretion of customer, gross value

$ 553,000

Amount of additional courses at the discretion of customer | treatment

1,381,000

Amount of additional courses at the discretion of customer, net of marketing cost

$ 551,000

Reimbursable marketing cost upon the exercise of options

$ 2,000

BARDA | TEMBEXA | Base Period | Scenario, Plan

Schedule of Investments

Contractual treatment commitment (treatment) | treatment

319,000

Deferred revenue

$ 127,000

BARDA | TEMBEXA | Maximum

Schedule of Investments

Contractual treatment commitment (treatment) | treatment

1,700,000

Contract term (in years)

10 years

National Stockpile | TEMBEXA | Base Period | Scenario, Plan

Schedule of Investments

Deferred revenue

$ 115,000

National Stockpile | Expense Reimbursement | Base Period | Scenario, Plan

Schedule of Investments

Reimbursable marketing expenses

$ 12,000

Emergent

Schedule of Investments

Up-front cash payment

$ 237,987

Gain (loss) on sale of assets

229,670

$ 229,700

Emergent | TEMBEXA | Base Period

Schedule of Investments

Up-front cash payment

$ 238,000

Quantity royalty rate, trigger (treatments) | treatment

1,700,000

Emergent | TEMBEXA | Base Period | Non- United States

Schedule of Investments

Gross profit royalty rate (as a percent)

15%

Emergent | TEMBEXA | Base Period | United States

Schedule of Investments

Gross profit royalty rate (as a percent)

20%

Emergent | BARDA | Base Period

Schedule of Investments

Maximum milestone proceeds upon the exercise of options

$ 124,000

SymBio Pharmaceuticals | Scenario, Plan

Schedule of Investments

Deferred revenue

$ 12,500

Emergent Biodefense Operations Lansing LLC

Schedule of Investments

Revenue recognized

$ 26

$ 200

Ohara Pharmaceutical Co., Ltd.

Schedule of Investments

License agreement, nonrefundable regulatory milestone payment to be received

$ 2,500

CR Sanjui | Scenario, Plan | Oncoceutics, Inc.

Schedule of Investments

Deferred revenue

$ 5,000

Significant Agreements- Schedul

Significant Agreements- Schedule of Assets and Liabilities Transferred in Accordance with Asset Purchase Agreement (Details) - Emergent - USD ($) $ in Thousands		3 Months Ended
	Sep. 26, 2022	Sep. 30, 2022
Schedule of Investments
Up-front cash payment	$ 237,987
Liabilities assumed by Emergent	1,423
Inventory transferred to Emergent	(5,227)
Prepaids transferred to Emergent	(511)
Transaction costs incurred	(4,002)
Net gain	$ 229,670	$ 229,700

DSTAT Contract Close-out - Narr

DSTAT Contract Close-out - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Contract close out liability	$ 853	$ 1,071	$ 853	$ 1,311	$ 4,539
Revised estimates	(122)	$ 10	(111)	$ (746)
Accrued Liabilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Contract close out liability	$ 900		$ 900

DSTAT Contract Close-out- Sched

DSTAT Contract Close-out- Schedule of Contract Close-out Cost Income Statement Location (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative
Contract close out cost	$ 799
Research & development
Collaborative Arrangement and Arrangement Other than Collaborative
Contract close out cost	791
General & administrative
Collaborative Arrangement and Arrangement Other than Collaborative
Contract close out cost	$ 8

DSTAT Contract Close-out- Sch_2

DSTAT Contract Close-out- Schedule of Accrual Activities for Contract Close-out Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Accrual Activities for Contract Close-out Cost
Beginning balance	$ 1,071	$ 1,311	$ 1,311	$ 4,539
Revised estimates	(122)	10	(111)	(746)
Payments	(96)	(250)		(2,482)
Ending balance	$ 853	$ 1,071	$ 853	$ 1,311

Restructuring Costs- Narrative

Restructuring Costs- Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 31, 2022 USD ($) employee	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Restructuring and Related Activities [Abstract]
Reduction in workforce | employee	20
One-time employee termination benefits		$ 600	$ 1,854	$ 400
Anticipated severance cost	$ 1,000		$ 1,000	$ 1,000

Restructuring Costs - Schedule

Restructuring Costs - Schedule of Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2022
Restructuring Cost and Reserve
Total restructuring expenses	$ 600	$ 1,854	$ 400
Research & development
Restructuring Cost and Reserve
Total restructuring expenses		1,768
General & administrative
Restructuring Cost and Reserve
Total restructuring expenses		$ 86

Restructuring Costs - Schedul_2

Restructuring Costs - Schedule of Accrual Activity for Restructuring Accrual (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2023	Mar. 31, 2023
Restructuring Reserve
Balance at December 31, 2022	$ 728	$ 1,442
Revised estimates	(89)	(73)
Payments	(395)	(641)
Balance at March 31, 2023	$ 244	$ 728