Chimerix (CMRX) 10-Q 7 May 20 2020 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Registrant Name	CHIMERIX INC
Entity Central Index Key	0001117480
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Common Stock, Shares Outstanding		61,930,339

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 24,553	$ 16,901
Short-term investments, available-for-sale	78,469	96,574
Accounts receivable	1,079	1,233
Prepaid expenses and other current assets	2,639	3,385
Total current assets	106,740	118,093
Property and equipment, net of accumulated depreciation	435	540
Operating lease right-of-use assets	578	709
Other long-term assets	16	34
Total assets	107,769	119,376
Current liabilities:
Accounts payable	1,124	2,398
Accrued liabilities	5,556	6,830
Total current liabilities	6,680	9,228
Lease-related obligations	48	196
Total liabilities	6,728	9,424
Stockholders’ equity:
Preferred stock, $0.001 par value, 10,000,000 shares authorized at March 31, 2020 and December 31, 2019; no shares issued and outstanding as of March 31, 2020 and December 31, 2019	0	0
Common stock, $0.001 par value, 200,000,000 shares authorized at March 31, 2020 and December 31, 2019; 61,930,339 and 61,590,013 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively	62	62
Additional paid-in capital	780,248	778,693
Accumulated other comprehensive (loss) gain, net	(11)	35
Accumulated deficit	(679,258)	(668,838)
Total stockholders’ equity	101,041	109,952
Total liabilities and stockholders’ equity	$ 107,769	$ 119,376

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
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)	61,930,339	61,590,013
Common stock, shares outstanding (in shares)	61,930,339	61,590,013

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Total revenues	$ 1,241	$ 2,356
Operating expenses:
Research and development	8,949	13,515
General and administrative	3,205	7,686
Total operating expenses	12,154	21,201
Loss from operations	(10,913)	(18,845)
Other income:
Interest income and other, net	493	1,152
Net loss	(10,420)	(17,693)
Other comprehensive loss:
Unrealized (loss) gain on debt investments, net	(46)	140
Comprehensive loss	$ (10,466)	$ (17,553)
Per share information:
Net loss, basic and diluted (in dollars per share)	$ (0.17)	$ (0.35)
Weighted-average shares outstanding, basic and diluted (in shares)	61,742,035	50,887,221
Contract revenue
Total revenues	$ 1,171	$ 2,356
Licensing revenue
Total revenues	$ 70	$ 0

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, 2018	$ 177,604	$ 51	$ 733,907	$ (92)	$ (556,262)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	4,073		4,073
Exercise of stock options	13		13
Employee stock purchase plan purchases	170		170
Comprehensive loss:
Unrealized gain (loss) on investments, net	140			140
Net loss	(17,693)				(17,693)
Comprehensive loss	(17,553)
Ending Balance at Mar. 31, 2019	164,307	51	738,163	48	(573,955)
Beginning Balance at Dec. 31, 2019	109,952	62	778,693	35	(668,838)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	1,326		1,326
Employee stock purchase plan purchases	229		229
Comprehensive loss:
Unrealized gain (loss) on investments, net	(46)			(46)
Net loss	(10,420)				(10,420)
Comprehensive loss	(10,466)
Ending Balance at Mar. 31, 2020	$ 101,041	$ 62	$ 780,248	$ (11)	$ (679,258)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net loss	$ (10,420)	$ (17,693)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation of property and equipment	112	149
Amortization of discount/premium on investments	(191)	(595)
Share-based compensation	1,326	4,073
Unrealized loss on equity investment	0	8
Lease-related amortization	(21)	(16)
Changes in operating assets and liabilities:
Accounts receivable	154	(1,095)
Prepaid expenses and other assets	762	59
Accounts payable and accrued liabilities	(2,542)	(624)
Net cash used in operating activities	(10,820)	(15,734)
Cash flows from investing activities:
Purchases of property and equipment	(7)	(97)
Purchases of short-term investments	(27,652)	(69,680)
Proceeds from maturities of short-term investments	45,902	23,950
Net cash provided by (used in) investing activities	18,243	(45,827)
Cash flows from financing activities:
Proceeds from exercise of stock options	0	13
Proceeds from employee stock purchase plan	229	170
Payments of deferred offering costs	0	(23)
Net cash provided by financing activities	229	160
Net increase (decrease) in cash and cash equivalents	7,652	(61,401)
Cash and cash equivalents:
Beginning of period	16,901	81,106
End of period	$ 24,553	$ 19,705

The Business and Summary of Sig

The Business and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
The Business and Summary of Significant Accounting Policies	The Business and Summary of Significant Accounting Policies Description of Business Chimerix, Inc. (the Company) is a development-stage biopharmaceutical company dedicated to accelerating the advancement of innovative medicines that make a meaningful impact in the lives of patients living with cancer and other serious diseases. The Company has two clinical-stage product candidates, dociparstat sodium (DSTAT) and brincidofovir (BCV). Dociparstat sodium is a potential first-in-class glycosaminoglycan compound derived from porcine heparin with known anti-inflammatory properties, but with substantially reduced risk of bleeding complications compared to commercially available forms of heparin. DSTAT is currently in development as a first-line therapy in acute myeloid leukemia (AML). DSTAT may enhance eradication of leukemic blasts and quiescent leukemic stem cells (LSCs) by making them more sensitive to chemotherapy. Specifically, DSTAT inhibits binding and/or interactions of proteins including CXCL12, P-selectins, HMGB1, and platelet factor 4. DSTAT may sensitize malignant blasts to chemotherapy by inhibiting AML survival pathways and reversing LSC quiescence leading to the observed increases in relapse-free survival (RFS) and overall survival (OS) in a Phase 2 study with DSTAT versus placebo. Randomized Phase 2 data suggests that DSTAT may also accelerate platelet recovery post chemotherapy via inhibition of platelet factor 4, a negative regulator of platelet production that impairs platelet recovery following chemotherapy. DSTAT is also being developed for acute lung injury (ALI) in COVID-19 patients. DSTAT has demonstrated potential in preclinical studies to address key inflammatory and coagulation disorders observed in patients with severe COVID-19. DSTAT has the potential to inhibit the hyperactive immune response and resulting inflammation, as well as address the underlying causes of coagulation disorders seen in COVID-19, but with substantially reduced risk of bleeding complications compared to commercially available forms of heparin . BCV is a lipid conjugate DNA polymerase inhibitor in development as a medical countermeasure for smallpox. The Company expects to continue its evaluation of external innovation in order to license, acquire or otherwise gain access to molecules that further broaden its pipeline of investigational agents in cancer or other serious 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, 2019 . 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 months ended March 31, 2020 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. Reclassifications Certain prior period amounts in the accompanying consolidated financial statements have been reclassified to conform to the current year presentation. These reclassifications had no effect on previously reported net income or stockholders' equity (deficit). 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. At March 31, 2020 the Company had cash equivalents including money market funds and U.S. Treasury securities and at December 31, 2019 , the Company had cash equivalents including money market funds, whose value is based on quoted market prices. At March 31, 2020 and December 31, 2019 , the Company had short term investments, including U.S. Treasury securities, whose value is based on quoted market prices. Accordingly, these securities are classified as Level 1. At March 31, 2020 and December 31, 2019 , the Company had short-term investments, including commercial paper and corporate bonds. As quoted prices are not available for these securities, they are valued using independent pricing models or other model-based valuation techniques such as the present value of future cash flows, adjusted for the security’s credit rating, prepayment assumptions and other factors such as credit loss assumptions. Accordingly, these securities are classified as Level 2. 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 March 31, 2020 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 17,963 $ 17,963 $ — $ — U.S. treasury securities 2,500 2,500 — — Total cash equivalents 20,463 20,463 — — Short-term investments U.S. treasury securities 12,047 12,047 — — Commercial paper 43,893 — 43,893 — Corporate bonds 22,529 — 22,529 — Total short-term investments 78,469 12,047 66,422 — Total assets $ 98,932 $ 32,510 $ 66,422 $ — Fair Value Measurements December 31, 2019 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 11,854 $ 11,854 $ — $ — Total cash equivalents 11,854 11,854 — — Short-term investments U.S. treasury securities 22,493 22,493 — — Commercial paper 43,119 — 43,119 — Corporate bonds 30,962 — 30,962 — Total short-term investments 96,574 22,493 74,081 — Total assets $ 108,428 $ 34,347 $ 74,081 $ — Accrued Liabilities Accrued liabilities consisted of the following (in thousands): March 31, 2020 December 31, 2019 Accrued research and development expenses $ 2,612 $ 1,868 Accrued compensation 1,734 3,626 Other accrued liabilities 1,210 1,336 Total accrued liabilities $ 5,556 $ 6,830 Revenue Recognition Policy The Company’s revenues generally consist of (i) contract revenue - revenue generated under federal contracts, and (ii) collaboration and licensing revenue - revenue related to non-refundable upfront fees, royalties and milestone payments earned under license agreements. 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. Biomedical Advanced Research and Development Authority (BARDA) In February 2011, the Company entered into a contract with BARDA for the advanced development of BCV as a medical countermeasure in the event of a smallpox release. Under the contract, the Company may receive up to $75.8 million in expense reimbursement and $5.3 million in fees over the performance of 1 base segment and 4 option segments. Exercise of each option segment is solely at the discretion of BARDA. Currently, option segments 1 through 3 have been exercised. The Company assessed the services in accordance with the authoritative guidance and concluded that there is a potential of 5 separate contracts ( 1 base segment and 4 option segments) within this agreement, each of which has a single performance obligation. The transaction price for each segment, based on the transaction price as defined in each segment contract, is allocated to the single performance obligation for each contract. The transaction price is recognized over time by measuring the progress toward complete satisfaction of the performance obligation. For reimbursable expenses, this occurs as qualifying research activities are conducted based on invoices from company vendors. For the fixed fee, the progress toward complete satisfaction is estimated based on the costs incurred to date relative to the total estimated costs per the terms of each contract. The Company typically invoices BARDA monthly as costs are incurred. Any amounts received in advance of performance are recorded as deferred revenue until earned. The base segment and first option segment were completed prior to adoption of ASC 606. The Company is currently performing under the second and third option segments of the contract during which the Company may receive up to a total of $23.9 million and $14.1 million in expense reimbursement and fees, respectively. The second option and third option segments are scheduled to end on May 31, 2020. SymBio Pharmaceuticals On September 30, 2019, the Company entered into a license agreement with SymBio Pharmaceuticals Limited (SymBio) for the exclusive worldwide rights to develop, manufacture and commercialize BCV for all human indications, excluding the prevention and treatment of orthopoxviruses, including smallpox. The Company assessed the agreement in accordance with the authoritative guidance and concluded that the SymBio contract includes multiple performance obligations. The SymBio contract has one fixed transaction amount of a $5.0 million upfront payment received in October 2019 and several variable transaction amounts, up to $180 million , due to the Company at certain regulatory and commercial milestones, along with low double-digit royalties, due to the Company on annual net sales. All variable transaction amounts are fully constrained, therefore the allocated transaction price is $5.0 million . The majority of the transaction price of the contract has been allocated to the combined performance obligation of the granting of the license to BCV and associated technology transfer which was recognized when the technology transfer was completed in the fourth quarter of 2019. The remainder of the upfront payment will be recognized as the technical assistance performance obligation is completed, which is expected to occur in the second quarter of 2020. The revenue from regulatory and commercial milestones and royalties from net sales will be recognized upon occurrence of the triggering events or when those transaction amounts are no longer fully constrained. As of March 31, 2020 , the Company had recognized approximately $5.0 million of revenue related to the upfront payment and $14,000 remained in deferred revenue in accrued liabilities. 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 March 31, 2020 , 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 Loss Per Share of Common Stock Basic net loss per share of common stock is computed by dividing net 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 loss per share of common stock is computed by dividing net 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 months ended March 31, 2020 and 2019 . Impact of Recently Issued 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 is currently evaluating the potential impact that this standard may have on its consolidated financial statements.

Investments

Investments	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The following tables summarize the Company's debt investments (in thousands): March 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 22,609 $ — $ (80 ) $ 22,529 U.S. treasury securities 11,996 51 — 12,047 Commercial paper 43,878 25 (10 ) 43,893 Total investments $ 78,483 $ 76 $ (90 ) $ 78,469 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 30,952 $ 19 $ (9 ) $ 30,962 Commercial paper 43,109 14 (4 ) 43,119 U.S. treasury securities 22,478 17 (2 ) 22,493 Total investments $ 96,539 $ 50 $ (15 ) $ 96,574 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): March 31, 2020 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 22,529 $ (80 ) $ — $ — $ 22,529 $ (80 ) Commercial paper 8,351 (10 ) — — 8,351 (10 ) Total $ 30,880 $ (90 ) $ — $ — $ 30,880 $ (90 ) Number of securities with unrealized losses 14 — 14 December 31, 2019 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 9,657 $ (9 ) $ — $ — $ 9,657 $ (9 ) Commercial paper 10,147 (4 ) — — 10,147 (4 ) U.S. treasury securities 2,994 (2 ) — — 2,994 (2 ) Total $ 22,798 $ (15 ) $ — $ — $ 22,798 $ (15 ) Number of securities with unrealized losses 9 — 9 The Company periodically reviews available-for-sale debt investments for other-than-temporary declines in fair value below the 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. At March 31, 2020 , the Company did not intend to sell, and was not more likely than not to be required to sell, the available-for-sale debt investments in an unrealized loss position before recovery of the cost basis of the securities, which may be at maturity. There were no such declines in value for the three months ended March 31, 2020 and 2019 . Unrealized gains and losses on debt investments are recorded to unrealized (loss) gain on debt investments, net in the Consolidated Statements of Operations and Comprehensive Loss. 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 March 31, 2020 (in thousands): Maturing in one year or less $ 78,469 Maturing after one year through two years — Total debt investments $ 78,469

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
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 2021. 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 March 31, 2020 was 1.03 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 $193,000 and $194,000 , respectively, for the three months ended March 31, 2020 and 2019 . 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 March 31, 2020 , the operating lease liabilities reflect a weighted-average discount rate of 13.07% . The following table sets forth the operating lease right-of-use assets and liabilities as of March 31, 2020 (in thousands): Assets Operating lease right-of-use assets $ 578 Liabilities Operating lease short-term liabilities (recorded within Accrued liabilities) $ 633 Operating lease long-term liabilities (recorded within Lease-related obligations) 48 Total operating lease liabilities $ 681 Operating lease payments over the remainder of the lease terms are as follows (in thousands): Years Ending December 31, As of March 31, 2020 2020 $ 541 2021 182 Total future minimum rental payments $ 723 Less amount of lease payments representing interest 42 Total present value of lease payments $ 681 As of December 31, 2019 , operating lease payments over the remainder of the lease terms were as follows (in thousands): Years Ending December 31, As of December 31, 2019 2020 $ 719 2021 182 Total future minimum rental payments $ 901 Less amount of lease payments representing interest 66 Total present value of lease payments $ 835 For the three months ended March 31, 2020 and 2019 , the Company made lease payments of approximately $178,000 and $192,000 , respectively, which are included in operating cash flows. Sublease The Company subleases 3,537 square feet of its office space under a non-cancelable operating lease that expires in February 2021. For the three months ended March 31, 2020 and 2019 , the Company recognized approximately $18,000 and $18,000 of income in Interest income and other, net on the Consolidated Statement of Operations and Comprehensive Loss. Total future minimum rentals under the non-cancelable operating sublease are presented below (in thousands): Years Ending December 31, As of March 31, 2020 2020 $ 61 2021 14 Total future minimum sublease rentals $ 75 Significance of Revenue Source The Company is the recipient of federal research contract funds from BARDA, the sole source of the Company's contract revenue. Periodic audits are required under the Company’s BARDA agreement and certain costs may be questioned as appropriate under the BARDA agreement. Management believes that such amounts in the current year, if any, are not significant. Accordingly, no provision for refundable amounts under the BARDA agreement had been made as of March 31, 2020 and December 31, 2019 .

Equity Transactions and Share-b

Equity Transactions and Share-based Compensation	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Equity Transactions and Share-based Compensation	Equity Transactions and Share-based Compensation 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 increases on January 1 of each calendar year by 4% of the total number of shares of capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s board of directors. On January 1, 2020 , the common stock reserved for issuance under the 2013 Plan was automatically increased by 2.5 million shares. As of March 31, 2020 , there was a total of 1.7 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 months ended March 31, 2020 . The Company issued approximately 8,000 shares of common stock pursuant to the exercise of stock options during the three months ended March 31, 2019 . 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 3.5 million shares of common stock to be purchased under the ESPP, of which 2.6 million shares remained available for purchase as of March 31, 2020 . The number of shares of common stock reserved for issuance automatically increases on January 1 of each calendar year, by the lesser of (a) 1% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, (b) 422,535 shares, or (c) a number determined by the Company’s board of directors that is less than (a) and (b). On January 1, 2020 , the common stock reserved for issuance under the ESPP was automatically increased 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 177,000 and 113,000 shares of common stock pursuant to the ESPP during the three months ended March 31, 2020 and 2019 , 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 approximately 163,000 and 168,000 shares of common stock pursuant to the vesting of RSUs during the three months ended March 31, 2020 and 2019 , respectively. 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 March 31, 2020 2019 Research and development expense $ 740 $ 1,270 General and administrative expense 586 2,803 Total share-based compensation expense $ 1,326 $ 4,073 The three months ended March 31, 2019 includes $1.8 million of share-based compensation expense related to the accelerated vesting and modification of stock options and RSUs of the Company's then President and CEO in connection with her severance agreement.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company estimates an annual effective tax rate of 0% for the year ending December 31, 2020 as the Company incurred losses for the three month period ended March 31, 2020 , and is forecasting an estimated net loss for both financial statement and tax purposes for the year ending December 31, 2020 . 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 March 31, 2020 , the Company had no unrecognized tax benefits that would reduce the Company’s effective tax rate if recognized. On March 27, 2020, President Trump signed into law the “Coronavirus Aid, Relief and Economic Security (CARES) Act.” The CARES Act, among other things, includes provisions relating to refundable payroll tax credits, deferment of employer side social security payments, net operating loss carryback periods, alternative minimum tax credit refunds, modifications to the net interest deduction limitations and technical corrections to tax depreciation methods for qualified improvement property. At this point, we do not expect the CARES Act to have a material impact on our financial results. We continue to examine the impact the CARES Act may have on our business.

Significant Agreements

Significant Agreements	3 Months Ended
	Mar. 31, 2020
Revenue Recognition [Abstract]
Significant Agreements	Significant Agreements The Regents of the University of California In May 2002, the Company entered into a license agreement with The Regents of the University of California (UC) under which the Company obtained an exclusive, worldwide license to UC’s patent rights in certain inventions (the UC Patent Rights) related to lipid-conjugated antiviral compounds and their use, including certain patents relating to BCV. The license agreement was terminated effective September 29, 2019. The termination of the license to the UC Patent Rights does not affect the Chimerix solely-owned patents covering BCV composition of matter that currently are set to expire in 2034. Biomedical Advanced Research and Development Authority (BARDA) In February 2011, the Company entered into a contract with BARDA for the advanced development of BCV as a medical countermeasure in the event of a smallpox release. Under the contract, BARDA will reimburse the Company, plus pay a fixed fee, for the research and development of BCV as a broad-spectrum therapeutic antiviral for the treatment of smallpox infections. The contract consists of an initial performance period, referred to as the base performance segment, plus up to four extension periods, referred to as option segments, each of which may be exercised at BARDA’s sole discretion. The Company must complete the agreed upon milestones and deliverables in each discrete work segment before the next option segment is eligible to be exercised. Under the contract as currently in effect, the Company may receive up to $75.8 million in expense reimbursement and $5.3 million in fees. The Company is currently performing under the second and third option segments of the contract during which the Company may receive up to a total of $23.9 million and $14.1 million in expense reimbursement and fees, respectively. The second and third option segments are scheduled to end on May 31, 2020. Of the $75.8 million in expense reimbursement and $5.3 million in fees that the Company may receive, approximately $74.3 million in expense reimbursement and fees has been funded. As of March 31, 2020 , of the total funding the Company had invoiced an aggregate of $71.3 million with respect to the base performance segment and the first three option segments. For the three months ended March 31, 2020 and 2019 , the Company recognized revenue under this contract of $1.2 million and $2.4 million , respectively. Cantex Pharmaceuticals, Inc. On July 26, 2019, the Company entered into a License and Development Agreement with Cantex Pharmaceuticals, Inc. (Cantex) pursuant to which the Company acquired exclusive worldwide rights to develop and commercialize, for any and all uses, a glycosaminoglycan compound known as DSTAT, which is currently being studied for the treatment of acute myeloid leukemia and acute lung injury in patients with COVID-19. Under the terms of the license agreement, the Company will be responsible for, and bear the future costs of, worldwide development and commercialization of DSTAT. In connection with the transaction, Cantex assigned to the Company all of its rights under its DSTAT supply agreements, including its bulk API agreement with Scientific Protein Laboratories LLC (SPL), pursuant to which SPL will exclusively produce DSTAT for the Company through October 2030. In consideration for the license rights, the Company made an upfront cash payment of $30.0 million to Cantex and issued to Cantex 10.0 million shares of its common stock. During 2019, the Company recognized 65.0 million of acquired in-process research and development expenses for the $30.0 million upfront cash payment, the fair value of the 10.0 million shares of common stock issued to Cantex and $0.1 million of transaction costs. The license agreement obligates the Company to pay Cantex regulatory milestone payments of up to $202.5 million upon receipt of product approvals in the United States, the European Union and Japan, and sales milestone payments of up to $385.0 million upon achievement of specified net sales levels. The Company also agreed to pay Cantex tiered royalties based on percentages of net sales beginning at 10% and not to exceed the high-teens. SymBio Pharmaceuticals On September 30, 2019, the Company entered into a license agreement with Symbio for the exclusive worldwide rights to develop, manufacture and commercialize BCV for all human indications, excluding the prevention and treatment of orthopoxviruses, including smallpox. Under the terms of the license agreement, SymBio will be responsible for, and bear the future costs of, worldwide development and commercialization of BCV in the licensed indications. Either party may terminate the license agreement upon the occurrence of a material breach by the other party (subject to standard cure periods), or upon certain events involving the bankruptcy or insolvency of the other party. SymBio may also terminate the license agreement without cause on a country-by-country basis upon ninety days ' prior notice. In exchange for the license to BCV rights, the Company received an upfront payment of $5.0 million in October 2019. In addition, the Company is eligible to receive up to $180.0 million in clinical, regulatory and commercial milestones worldwide, as well as low double-digit royalties and additional milestones based on commercial sales. Since entering into the license agreement in September 2019, the Company has recognized approximately $5.0 million of revenue related to the upfront payment and as of March 31, 2020 , 14,000 remained in deferred revenue in accrued liabilities. University of Michigan In 2006, the Company entered into a license agreement with The Regents of the University of Michigan (UM) under which the Company obtained an exclusive, worldwide license to UM’s patent rights in certain inventions (UM Patent Rights) related to certain compounds originally synthesized at UM. Under the license agreement, the Company is permitted to research, develop, manufacture and commercialize products utilizing the UM Patent Rights, and to sublicense such rights subject to certain sublicensing fees and royalty payments. In consideration for the rights granted to the Company, under the license agreement as amended in December 2016, the Company paid UM $50,000 in fees in 2016 and in January 2017 issued UM an aggregate of 33,058 shares of its common stock. In connection with the Company's commercialization or sublicensing of certain products covered by the license agreement, including CMX521, the Company could be required to pay royalties on net sales of such products ranging from 0.25% to 2% . Beginning in 2024, the Company is also subject to certain minimum annual royalty payments. The UM license agreement requires that the Company use commercially reasonable efforts to develop and make commercially available licensed products as soon as practicable. Specifically, the Company has agreed to make the first commercial sale of a licensed product by June of 2026. UM may terminate the license agreement if the Company materially breaches the license agreement. The Company is currently in compliance with its milestone requirements.

Restructuring Costs

Restructuring Costs	3 Months Ended
	Mar. 31, 2020
Restructuring and Related Activities [Abstract]
Restructuring Costs	Restructuring Costs In May 2019, the Company made the decision to discontinue the development of oral and IV BCV development programs for the treatment of Adenovirus (AdV) in stem-cell transplant (HCT) patients. The Company's development efforts with respect to BCV are now focused on the treatment of smallpox. As a result, the Company restructured its operations, which included a reduction in workforce of 43 full-time employees and the accrual of expenses to close-out the clinical trials for the oral and IV development programs of BCV in AdV (study 210, study 211, AdAPT) and other supportive BCV development programs. In 2019, the Company recorded charges for one-time employee termination benefits of $3.3 million , contract close-out costs of $2.0 million , other BCV development costs of $0.3 million , and losses on disposals of fixed assets of $0.3 million during 2019. The $2.0 million of contract close-out costs were recorded through an increase in liabilities of $1.5 million with the remainder recognized through the expensing of prepaid balances. As of December 31, 2019 , the Company had a clinical trial accrual balance related to the AdAPT, 210 and 211 trial terminations of $27,000 , other development costs accrual balance of $0.1 million , and severance accrual balance of $0.2 million . Additionally, as of December 31, 2019 prepaid balances of $1.3 million for unused deposits have been reclassed to other receivables, which was recorded in prepaid expenses and other current assets on the Consolidated Balance Sheet. The following table summarizes the restructuring charges (in thousands) recorded in 2019 during the period subsequent to the restructuring in May 2019: Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Fixed Asset Disposals Total Research and development $ 1,437 $ 2,021 $ 339 $ — $ 3,797 General and administrative 1,909 — — — 1.909 Interest income and other, net — — — 250 250 Total restructuring expenses $ 3,346 $ 2,021 $ 339 $ 250 $ 5,956 The following table sets forth the accrual activity for employee termination benefits and contract close-out costs (in thousands) for 2019. Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Fixed Asset Disposals Total Balance at January 1, 2019 $ — $ — $ — $ — $ — Accruals 3,335 2,131 315 — 5,781 Revised estimates 11 (621 ) 24 250 (336 ) Payments (3,163 ) (1,483 ) (229 ) (250 ) (5,125 ) Balance at December 31, 2019 $ 183 $ 27 $ 110 $ — $ 320 The following table sets forth the accrual activity for employee termination benefits and contract close-out costs (in thousands) for the three months ended March 31, 2020 . All amounts are expected to be fully paid by the end of the second quarter of 2020 and no additional charges are expected to be incurred. Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Total Balance at December 31, 2019 $ 183 $ 27 $ 110 $ 320 Revised estimates — (14 ) — (14 ) Payments (114 ) (4 ) (100 ) (218 ) Balance at March 31, 2020 $ 69 $ 9 $ 10 $ 88 For the three months ended March 31, 2020 , the revised accrual estimates resulted in a decrease to research and development expenses of $14,000 . As of March 31, 2020 prepaid balances of $1.3 million for unused deposits remained in prepaid expenses and other current assets on the Consolidated Balance Sheet and are expected to be refunded during the second quarter of 2020.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The 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 March 31, 2020 , 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 (Policy)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	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, 2019 . 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 months ended March 31, 2020 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.
Reclassifications	Reclassifications Certain prior period amounts in the accompanying consolidated financial statements have been reclassified to conform to the current year presentation. These reclassifications had no effect on previously reported net income or stockholders' equity (deficit).
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.
Revenue Recognition	Revenue Recognition Policy The Company’s revenues generally consist of (i) contract revenue - revenue generated under federal contracts, and (ii) collaboration and licensing revenue - revenue related to non-refundable upfront fees, royalties and milestone payments earned under license agreements. 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 March 31, 2020 , 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 Loss Per Share of Common Stock	Basic and Diluted Net Loss Per Share of Common Stock Basic net loss per share of common stock is computed by dividing net 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 loss per share of common stock is computed by dividing net 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 months ended March 31, 2020 and 2019 .
Impact of Recently Issued Accounting Standards and Impact of Recently Adopted Accounting Standards	Impact of Recently Issued 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 is currently evaluating the potential impact that this standard may have on its consolidated financial statements.

The Business and Summary of S_3

The Business and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
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 March 31, 2020 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 17,963 $ 17,963 $ — $ — U.S. treasury securities 2,500 2,500 — — Total cash equivalents 20,463 20,463 — — Short-term investments U.S. treasury securities 12,047 12,047 — — Commercial paper 43,893 — 43,893 — Corporate bonds 22,529 — 22,529 — Total short-term investments 78,469 12,047 66,422 — Total assets $ 98,932 $ 32,510 $ 66,422 $ — Fair Value Measurements December 31, 2019 Total Quoted Prices in Significant Other Significant Cash equivalents Money market funds $ 11,854 $ 11,854 $ — $ — Total cash equivalents 11,854 11,854 — — Short-term investments U.S. treasury securities 22,493 22,493 — — Commercial paper 43,119 — 43,119 — Corporate bonds 30,962 — 30,962 — Total short-term investments 96,574 22,493 74,081 — Total assets $ 108,428 $ 34,347 $ 74,081 $ —
Schedule of accrued liabilities	Accrued liabilities consisted of the following (in thousands): March 31, 2020 December 31, 2019 Accrued research and development expenses $ 2,612 $ 1,868 Accrued compensation 1,734 3,626 Other accrued liabilities 1,210 1,336 Total accrued liabilities $ 5,556 $ 6,830

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Summary of short-term and long-term investments	The following tables summarize the Company's debt investments (in thousands): March 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 22,609 $ — $ (80 ) $ 22,529 U.S. treasury securities 11,996 51 — 12,047 Commercial paper 43,878 25 (10 ) 43,893 Total investments $ 78,483 $ 76 $ (90 ) $ 78,469 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate bonds $ 30,952 $ 19 $ (9 ) $ 30,962 Commercial paper 43,109 14 (4 ) 43,119 U.S. treasury securities 22,478 17 (2 ) 22,493 Total investments $ 96,539 $ 50 $ (15 ) $ 96,574
Summary 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): March 31, 2020 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 22,529 $ (80 ) $ — $ — $ 22,529 $ (80 ) Commercial paper 8,351 (10 ) — — 8,351 (10 ) Total $ 30,880 $ (90 ) $ — $ — $ 30,880 $ (90 ) Number of securities with unrealized losses 14 — 14 December 31, 2019 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate bonds $ 9,657 $ (9 ) $ — $ — $ 9,657 $ (9 ) Commercial paper 10,147 (4 ) — — 10,147 (4 ) U.S. treasury securities 2,994 (2 ) — — 2,994 (2 ) Total $ 22,798 $ (15 ) $ — $ — $ 22,798 $ (15 ) Number of securities with unrealized losses 9 — 9
Summary of the scheduled maturity of company investments	The following table summarizes the scheduled maturity for the Company's debt investments at March 31, 2020 (in thousands): Maturing in one year or less $ 78,469 Maturing after one year through two years — Total debt investments $ 78,469

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Operating Lease Right-of-Use Assets and Liabilities	The following table sets forth the operating lease right-of-use assets and liabilities as of March 31, 2020 (in thousands): Assets Operating lease right-of-use assets $ 578 Liabilities Operating lease short-term liabilities (recorded within Accrued liabilities) $ 633 Operating lease long-term liabilities (recorded within Lease-related obligations) 48 Total operating lease liabilities $ 681
Operating Lease Maturity	Operating lease payments over the remainder of the lease terms are as follows (in thousands): Years Ending December 31, As of March 31, 2020 2020 $ 541 2021 182 Total future minimum rental payments $ 723 Less amount of lease payments representing interest 42 Total present value of lease payments $ 681 As of December 31, 2019 , operating lease payments over the remainder of the lease terms were as follows (in thousands): Years Ending December 31, As of December 31, 2019 2020 $ 719 2021 182 Total future minimum rental payments $ 901 Less amount of lease payments representing interest 66 Total present value of lease payments $ 835
Sublease Income	Total future minimum rentals under the non-cancelable operating sublease are presented below (in thousands): Years Ending December 31, As of March 31, 2020 2020 $ 61 2021 14 Total future minimum sublease rentals $ 75

Equity Transactions and Share_2

Equity Transactions and Share-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2020
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 March 31, 2020 2019 Research and development expense $ 740 $ 1,270 General and administrative expense 586 2,803 Total share-based compensation expense $ 1,326 $ 4,073

Restructuring Costs (Tables)

Restructuring Costs (Tables)	3 Months Ended
	Mar. 31, 2020
Restructuring and Related Activities [Abstract]
Restructuring and Related Costs	The following table summarizes the restructuring charges (in thousands) recorded in 2019 during the period subsequent to the restructuring in May 2019: Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Fixed Asset Disposals Total Research and development $ 1,437 $ 2,021 $ 339 $ — $ 3,797 General and administrative 1,909 — — — 1.909 Interest income and other, net — — — 250 250 Total restructuring expenses $ 3,346 $ 2,021 $ 339 $ 250 $ 5,956
Schedule of Restructuring Reserve by Type of Cost	The following table sets forth the accrual activity for employee termination benefits and contract close-out costs (in thousands) for 2019. Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Fixed Asset Disposals Total Balance at January 1, 2019 $ — $ — $ — $ — $ — Accruals 3,335 2,131 315 — 5,781 Revised estimates 11 (621 ) 24 250 (336 ) Payments (3,163 ) (1,483 ) (229 ) (250 ) (5,125 ) Balance at December 31, 2019 $ 183 $ 27 $ 110 $ — $ 320 The following table sets forth the accrual activity for employee termination benefits and contract close-out costs (in thousands) for the three months ended March 31, 2020 . All amounts are expected to be fully paid by the end of the second quarter of 2020 and no additional charges are expected to be incurred. Employee Termination Benefits Clinical Trial Close-out Costs Other Development Costs Total Balance at December 31, 2019 $ 183 $ 27 $ 110 $ 320 Revised estimates — (14 ) — (14 ) Payments (114 ) (4 ) (100 ) (218 ) Balance at March 31, 2020 $ 69 $ 9 $ 10 $ 88

The Business and Summary of S_4

The Business and Summary of Significant Accounting Policies - Description of Business (Details)	3 Months Ended
	Mar. 31, 2020product_candidate
Accounting Policies [Abstract]
Number of product candidates	2

The Business and Summary of S_5

The Business and Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Separate Account Investment [Line Items]
Short-term investments	$ 78,469	$ 96,574
Fair value, measurements, recurring
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	20,463	11,854
Short-term investments	78,469	96,574
Total assets	98,932	108,428
Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	20,463	11,854
Short-term investments	12,047	22,493
Total assets	32,510	34,347
Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0	0
Short-term investments	66,422	74,081
Total assets	66,422	74,081
Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0	0
Short-term investments	0	0
Total assets	0	0
Money market funds | Fair value, measurements, recurring
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	17,963	11,854
Money market funds | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	17,963	11,854
Money market funds | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0	0
Money market funds | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0	0
U.S. treasury securities | Fair value, measurements, recurring
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	2,500
Short-term investments	12,047	22,493
U.S. treasury securities | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	2,500
Short-term investments	12,047	22,493
U.S. treasury securities | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0
Short-term investments	0	0
U.S. treasury securities | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment [Line Items]
Cash equivalents	0
Short-term investments	0	0
Commercial paper | Fair value, measurements, recurring
Fair Value, Separate Account Investment [Line Items]
Short-term investments	43,893	43,119
Commercial paper | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	0	0
Commercial paper | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	43,893	43,119
Commercial paper | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	0	0
Corporate bonds | Fair value, measurements, recurring
Fair Value, Separate Account Investment [Line Items]
Short-term investments	22,529	30,962
Corporate bonds | Fair value, measurements, recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	0	0
Corporate bonds | Fair value, measurements, recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	22,529	30,962
Corporate bonds | Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment [Line Items]
Short-term investments	$ 0	$ 0

The Business and Summary of S_6

The Business and Summary of Significant Accounting Policies - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accrued research and development expenses	$ 2,612	$ 1,868
Accrued compensation	1,734	3,626
Other accrued liabilities	1,210	1,336
Total accrued liabilities	$ 5,556	$ 6,830

The Business and Summary of S_7

The Business and Summary of Significant Accounting Policies - Revenue Recognition (Details)	3 Months Ended		6 Months Ended	110 Months Ended	112 Months Ended
	Mar. 31, 2020USD ($)	Mar. 31, 2019USD ($)	Mar. 31, 2020USD ($)	Mar. 31, 2020USD ($)	May 31, 2020USD ($)base_segmentrevenue_contractoption_segment	Sep. 30, 2019USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	$ 1,241,000	$ 2,356,000
Licensing
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	70,000	0
BARDA
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	1,200,000	$ 2,400,000		$ 71,300,000
BARDA | Scenario, Forecast
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues					$ 74,300,000
Total number of base segments | base_segment					1
Total number of option segments | option_segment					4
Total number of separate contracts | revenue_contract					5
BARDA | Expense reimbursement | Scenario, Forecast
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues					$ 75,800,000
BARDA | Fees | Scenario, Forecast
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues					5,300,000
BARDA Second Option Segment | Scenario, Forecast
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues					23,900,000
BARDA Third Option Segment | Scenario, Forecast
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues					$ 14,100,000
SymBio Pharmaceuticals
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Initial upfront payment to be received	5,000,000		$ 5,000,000	5,000,000		$ 5,000,000
Payment to be received upon achievement of milestones	180,000,000		180,000,000	180,000,000		$ 180,000,000
SymBio Pharmaceuticals | Licensing
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues			5,000,000
Deferred revenue	$ 14,000		$ 14,000	$ 14,000

Investments - Summary of Availa

Investments - Summary of Available-for-Sale securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Amortized Cost	$ 78,483	$ 96,539
Gross Unrealized Gains	76	50
Gross Unrealized Losses	(90)	(15)
Estimated Fair Value	78,469	96,574
Corporate bonds
Schedule of Investments [Line Items]
Amortized Cost	22,609	30,952
Gross Unrealized Gains	0	19
Gross Unrealized Losses	(80)	(9)
Estimated Fair Value	22,529	30,962
U.S. treasury securities
Schedule of Investments [Line Items]
Amortized Cost	11,996	22,478
Gross Unrealized Gains	51	17
Gross Unrealized Losses	0	(2)
Estimated Fair Value	12,047	22,493
Commercial paper
Schedule of Investments [Line Items]
Amortized Cost	43,878	43,109
Gross Unrealized Gains	25	14
Gross Unrealized Losses	(10)	(4)
Estimated Fair Value	$ 43,893	$ 43,119

Investments - Summary of Invest

Investments - Summary of Investments with Unrealized Losses, Aggregated by Investment Type and the Length of Time (Details) $ in Thousands	Mar. 31, 2020USD ($)security	Dec. 31, 2019USD ($)security
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	$ 30,880	$ 22,798
Unrealized loss, less than 12 months	(90)	(15)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	30,880	22,798
Unrealized loss, total	$ (90)	$ (15)
Number of securities with unrealized losses, less than 12 months | security	14	9
Number of securities with unrealized losses, greater than 12 months | security	0	0
Number of securities with unrealized losses, total | security	14	9
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	$ 22,529	$ 9,657
Unrealized loss, less than 12 months	(80)	(9)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	22,529	9,657
Unrealized loss, total	(80)	(9)
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	8,351	10,147
Unrealized loss, less than 12 months	(10)	(4)
Fair value, greater than 12 months	0	0
Unrealized loss, greater than 12 months	0	0
Fair value, total	8,351	10,147
Unrealized loss, total	$ (10)	(4)
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months		2,994
Unrealized loss, less than 12 months		(2)
Fair value, greater than 12 months		0
Unrealized loss, greater than 12 months		0
Fair value, total		2,994
Unrealized loss, total		$ (2)

Investments - Schedule of Inves

Investments - Schedule of Investment Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Maturing in one year or less	$ 78,469
Maturing after one year through two years	0
Total debt investments	$ 78,469	$ 96,574

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)ft²	Mar. 31, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Weighted average remaining lease term	1 year 11 days
Rent expense under non-cancelable operating leases	$ 193	$ 194
Weighted average discount rate	13.07%
Lease payments	$ 178	192
Area of sublease space (in sq ft) | ft²	3,537
Sublease income	$ 18	$ 18

Commitments and Contingencies_2

Commitments and Contingencies - Operating Lease Right-of-Use Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Operating lease right-of-use assets	$ 578	$ 709
Liabilities
Operating lease short-term liabilities (recorded within Accrued liabilities)	633
Operating lease long-term liabilities (recorded within Lease-related obligations)	48
Total present value of lease payments	$ 681	$ 835

Commitments and Contingencies_3

Commitments and Contingencies - Maturity Analysis of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2020	$ 541	$ 719
2021	182	182
Total future minimum rental payments	723	901
Less amount of lease payments representing interest	42	66
Total present value of lease payments	$ 681	$ 835

Commitments and Contingencies_4

Commitments and Contingencies - Minimum Sublease Rentals (Details) $ in Thousands	Mar. 31, 2020USD ($)
Commitments and Contingencies Disclosure [Abstract]
2020	$ 61
2021	14
Total future minimum sublease rentals	$ 75

Equity Transactions and Share_3

Equity Transactions and Share-based Compensation (Details) - USD ($) $ in Millions	Jan. 01, 2019	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued for restricted stock units (in shares)		163,000	168,000
Acceleration compensation			$ 1.8
The 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Evergreen option provision, equity increase		4.00%
Additional shares authorized (in shares)	2,500,000
Number of shares reserved for future issuance (in shares)		1,700,000
Shares issued pursuant to the exercise of stock options (in shares)		0	8,000
The 2013 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Evergreen option provision, equity increase		1.00%
Additional shares authorized (in shares)	422,535
Number of shares reserved for future issuance (in shares)		2,600,000
Number of shares authorized to be granted (in shares)		3,500,000
Number of shares reserved for issuance, annual increase (in shares)		422,535
Participation term		2 years
Percentage of pay that employee can contribute, maximum		15.00%
Discounted purchase price from market price, offering date		15.00%
Discounted purchase price from market price, purchase date		15.00%
Purchase interval		6 months
Shares issued pursuant to employee stock purchase plan (in shares)		177,000	113,000

Equity Transactions and Share_4

Equity Transactions and Share-based Compensation - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total share-based compensation expense	$ 1,326	$ 4,073
Research and development expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total share-based compensation expense	740	1,270
General and administrative expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total share-based compensation expense	$ 586	$ 2,803

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020
Income Tax Contingency [Line Items]
Federal or state income taxes	$ 0
Unrecognized tax benefits	$ 0
Scenario, Forecast
Income Tax Contingency [Line Items]
Estimated annual effective tax rate		0.00%

Significant Agreements (Details

Significant Agreements (Details)	Sep. 30, 2019USD ($)	Jul. 26, 2019USD ($)shares	Jan. 31, 2017shares	Feb. 28, 2011extension	Mar. 31, 2020USD ($)	Mar. 31, 2019USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2016USD ($)	Mar. 31, 2020USD ($)	May 31, 2020USD ($)
Long-term Purchase Commitment [Line Items]
Total revenues					$ 1,241,000	$ 2,356,000
Licensing
Long-term Purchase Commitment [Line Items]
Total revenues					70,000	0
BARDA
Long-term Purchase Commitment [Line Items]
Number of extension periods | extension				4
Total revenues					1,200,000	$ 2,400,000			$ 71,300,000
Cantex Pharmaceuticals Inc.
Long-term Purchase Commitment [Line Items]
Upfront cash payment for license and development agreement		$ 30,000,000
Shares issued for license and development agreement (in shares) | shares		10,000,000
Acquired in-process research and development		$ 65,000,000
Transaction costs		100,000
Payments to be made for regulatory milestones (up to)		202,500,000
Payments to be made upon achievement of specified net sales levels (up to)		$ 385,000,000
Royalty percentage to be paid (at least)		10.00%
SymBio Pharmaceuticals
Long-term Purchase Commitment [Line Items]
Termination notice period	90 days
Initial upfront payment to be received	$ 5,000,000				5,000,000		$ 5,000,000		5,000,000
Payment to be received upon achievement of milestones	$ 180,000,000				180,000,000		180,000,000		180,000,000
SymBio Pharmaceuticals | Licensing
Long-term Purchase Commitment [Line Items]
Total revenues							5,000,000
Deferred revenue					$ 14,000		$ 14,000		$ 14,000
The Regents of the University of Michigan
Long-term Purchase Commitment [Line Items]
Upfront cash payment for license and development agreement								$ 50,000
Shares issued for license and development agreement (in shares) | shares			33,058
The Regents of the University of Michigan | Minimum
Long-term Purchase Commitment [Line Items]
Royalty percentage to be paid (at least)								0.25%
The Regents of the University of Michigan | Maximum
Long-term Purchase Commitment [Line Items]
Royalty percentage to be paid (at least)								2.00%
Scenario, Forecast | BARDA
Long-term Purchase Commitment [Line Items]
Total revenues										$ 74,300,000
Scenario, Forecast | BARDA | Expense reimbursement
Long-term Purchase Commitment [Line Items]
Total revenues										75,800,000
Scenario, Forecast | BARDA | Fees
Long-term Purchase Commitment [Line Items]
Total revenues										5,300,000
Scenario, Forecast | BARDA Second Option Segment
Long-term Purchase Commitment [Line Items]
Total revenues										23,900,000
Scenario, Forecast | BARDA Third Option Segment
Long-term Purchase Commitment [Line Items]
Total revenues										$ 14,100,000

Restructuring Costs (Details)

Restructuring Costs (Details)	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2019employee	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Restructuring Cost and Reserve [Line Items]
Reduction in workforce | employee	43
One-time employee termination benefits			$ 3,346,000
Accrued contract close-out costs			2,021,000
Other BCV development costs			339,000
Fixed Asset Disposals			250,000
Accrual balance		$ 88,000	320,000	$ 0
Revised estimates		(14,000)	(336,000)
Trial Terminations
Restructuring Cost and Reserve [Line Items]
Change in accrual balance			1,500,000
Accrual balance		9,000	27,000	0
Revised estimates		(14,000)	(621,000)
Other Development Costs
Restructuring Cost and Reserve [Line Items]
Accrual balance		10,000	110,000	0
Revised estimates		0	24,000
Severance Accrual Balance
Restructuring Cost and Reserve [Line Items]
Accrual balance		69,000	183,000	$ 0
Revised estimates		0	11,000
Restatement Adjustment
Restructuring Cost and Reserve [Line Items]
Unused deposits		$ (1,300,000)	$ (1,300,000)

Restructuring Costs - Summary o

Restructuring Costs - Summary of Restructuring Charges (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Restructuring Cost and Reserve [Line Items]
Employee Termination Benefits	$ 3,346
Clinical Trial Close-out Costs	2,021
Other Development Costs	339
Fixed Asset Disposals	250
Total	5,956
Research and development expense
Restructuring Cost and Reserve [Line Items]
Employee Termination Benefits	1,437
Clinical Trial Close-out Costs	2,021
Other Development Costs	339
Fixed Asset Disposals	0
Total	3,797
General and administrative expense
Restructuring Cost and Reserve [Line Items]
Employee Termination Benefits	1,909
Clinical Trial Close-out Costs	0
Other Development Costs	0
Fixed Asset Disposals	0
Total	1,909
Interest income and other, net
Restructuring Cost and Reserve [Line Items]
Employee Termination Benefits	0
Clinical Trial Close-out Costs	0
Other Development Costs	0
Fixed Asset Disposals	250
Total	$ 250

Restructuring Costs - Accrual A

Restructuring Costs - Accrual Activity for Restructuring Accrual (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning balance	$ 320,000	$ 0
Accruals		5,781,000
Revised estimates	(14,000)	(336,000)
Payments	(218,000)	(5,125,000)
Ending balance	88,000	320,000
Employee Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	183,000	0
Accruals		3,335,000
Revised estimates	0	11,000
Payments	(114,000)	(3,163,000)
Ending balance	69,000	183,000
Clinical Trial Close-out Costs
Restructuring Reserve [Roll Forward]
Beginning balance	27,000	0
Accruals		2,131,000
Revised estimates	(14,000)	(621,000)
Payments	(4,000)	(1,483,000)
Ending balance	9,000	27,000
Other Development Costs
Restructuring Reserve [Roll Forward]
Beginning balance	110,000	0
Accruals		315,000
Revised estimates	0	24,000
Payments	(100,000)	(229,000)
Ending balance	10,000	110,000
Fixed Asset Disposals
Restructuring Reserve [Roll Forward]
Beginning balance	$ 0	0
Accruals		0
Revised estimates		250,000
Payments		(250,000)
Ending balance		$ 0