SCYNEXIS (SCYX) 10-Q 17 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 01, 2021
Cover [Abstract]
Entity Registrant Name	SCYNEXIS, Inc.
Trading Symbol	SCYX
Entity Central Index Key	0001178253
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Document Type	10-Q
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		20,630,750
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity File Number	001-36365
Entity Tax Identification Number	56-2181648
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	1 Evertrust Plaza
Entity Address, Address Line Two	13th Floor
Entity Address, City or Town	Jersey City
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07302-6548
City Area Code	201
Local Phone Number	884-5485
Document Quarterly Report	true
Document Transition Report	false
Title of Each Class	Common Stock, par value $0.001 per share
Name of Each Exchange on Which Registered	NASDAQ

Unaudited Condensed Consolidate

Unaudited Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 92,011	$ 93,041
Prepaid expenses and other current assets	3,310	5,165
Restricted cash	55	0
Total current assets	95,376	98,206
Other assets	692	573
Deferred offering costs	187	187
Restricted cash	218	273
Property and equipment, net	271	298
Intangible assets	378	0
Operating lease right-of-use asset (See Note 6)	2,950	2,999
Total assets	100,072	102,536
Current liabilities:
Accounts payable	6,516	4,639
Accrued expenses	2,134	4,141
Warrant liabilities	16,225	17,564
Operating lease liability, current portion (See Note 6)	57	52
Total current liabilities	24,932	26,396
Other liabilties	140	0
Warrant liabilities	33,635	33,592
Convertible debt and derivative liability (See Note 5)	12,226	16,516
Operating lease liability (See Note 6)	3,215	3,274
Total liabilities	74,148	79,778
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value, authorized 5,000,000 shares as of March 31, 2021 and December 31, 2020; 0 shares issued and outstanding as of March 31, 2021 and December 31, 2020	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized as of March 31, 2021 and December 31, 2020; 20,625,637 and 19,663,698 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	21	20
Additional paid-in capital	357,192	349,351
Accumulated deficit	(331,289)	(326,613)
Total stockholders’ equity	25,924	22,758
Total liabilities and stockholders’ equity	$ 100,072	$ 102,536

Unaudited Condensed Consolida_2

Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
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)	100,000,000	100,000,000
Common stock, shares issued (in shares)	20,625,637	19,663,698
Common stock, shares outstanding (in shares)	20,625,637	19,663,698

Unaudited Condensed Consolida_3

Unaudited Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Revenue	$ 12,050	$ 0
Operating expenses:
Research and development	6,948	9,866
Selling, general and administrative	6,696	2,613
Total operating expenses	13,644	12,479
Loss from operations	(1,594)	(12,479)
Other expense (income):
Loss on extinguishment of debt	2,725	0
Amortization of debt issuance costs and discount	256	278
Interest income	(7)	(147)
Interest expense	214	210
Other income	0	(350)
Warrant liabilities fair value adjustment	(1,296)	(4,768)
Derivative liabilities fair value adjustment	90	(700)
Total other expense (income)	1,982	(5,477)
Loss before taxes	(3,576)	(7,002)
Income tax expense	1,100	0
Net loss	$ (4,676)	$ (7,002)
Net loss per share attributable to common stockholders – basic
Net loss per share – basic	$ (0.18)	$ (0.72)
Net loss per share attributable to common stockholders – diluted
Net loss per share – diluted	$ (0.23)	$ (0.72)
Weighted average common shares outstanding – basic and diluted
Basic	25,802,700	9,744,577
Diluted	26,523,920	9,744,577

Unaudited Condensed Consolida_4

Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net loss	$ (4,676)	$ (7,002)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	27	28
Stock-based compensation expense	398	410
Accretion of investments discount	0	(31)
Amortization of debt issuance costs and discount	256	278
Change in fair value of warrant liabilities	(1,296)	(4,768)
Change in fair value of derivative liabilities	90	(700)
Noncash operating lease expense for right-of-use asset	49	48
Loss on extinguishment of debt	2,725	0
Changes in operating assets and liabilities:
Prepaid expenses, other assets, deferred costs, and other	1,736	1,734
Accounts payable, accrued expenses, and other	(68)	(4,054)
Net cash used in operating activities	(759)	(14,057)
Cash flows from investing activities:
Maturities of investments	0	6,477
Purchases of property and equipment	0	(4)
Purchase of intangible assets	(200)	0
Purchases of investments	0	(14,235)
Net cash used in investing activities	(200)	(7,762)
Cash flows from financing activities:
Proceeds from common stock issued	0	214
Payments of offering costs and underwriting discounts and commissions	(62)	(7)
Proceeds from common stock issuance under employee stock purchase plan	6	18
Repurchase of shares to satisfy tax withholdings	(15)	(73)
Net cash (used in) provided by financing activities	(71)	152
Net decrease in cash, cash equivalents, and restricted cash	(1,030)	(21,667)
Cash, cash equivalents, and restricted cash at beginning of period	93,314	42,193
Cash, cash equivalents, and restricted cash at end of period	92,284	20,526
Supplemental cash flow information:
Cash paid for interest	420	420
Cash received for interest	5	129
Noncash financing and investing activities:
Common stock issued for settlement of senior convertible notes	7,452	0
Purchased intangible assets included in accounts payable and accrued expenses	178	0
Deferred offering and issuance costs included in accounts payable and accrued expenses	$ 0	$ 40

Description of Business and Bas

Description of Business and Basis of Preparation	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business and Basis of Preparation	1. Description of Business and Basis of Preparation Organization SCYNEXIS, Inc. (“SCYNEXIS” or the “Company”) is a Delaware corporation formed on November 4, 1999. SCYNEXIS is a biotechnology company, headquartered in Jersey City, New Jersey, pioneering innovative medicines to overcome and prevent difficult-to-treat and drug-resistant infections. The Company is developing its lead product candidate, ibrexafungerp, as the first representative of a novel oral and intravenous triterpenoid antifungal family for the treatment of several fungal infections, including serious and life-threatening invasive fungal infections. The Company has incurred significant losses and negative cash flows from operations since its initial public offering in May 2014 and expects to continue to incur losses and negative cash flows for the foreseeable future. As a result, the Company had an accumulated deficit of $331.3 million at March 31, 2021 and limited capital resources to fund ongoing operations. These capital resources primarily comprised cash and cash equivalents of $92.0 million at March 31, 2021. While the Company believes its capital resources are sufficient to fund the Company’s on-going operations for a period of at least 12 months subsequent to the issuance of the accompanying unaudited condensed consolidated financial statements, the Company's liquidity could be materially affected over this period by, among other things: (1) its ability to raise additional capital through equity offerings, debt financings, or other non-dilutive third-party funding; (2) costs associated with new or existing strategic alliances, or licensing and collaboration arrangements; (3) negative regulatory events or unanticipated costs related to its development of ibrexafungerp; (4) its ability to potentially commercialize ibrexafungerp for the treatment of vaginal yeast infections and; (5) any other unanticipated material negative events or costs. One or more of these events or costs could materially affect the Company’s liquidity. If the Company is unable to meet its obligations when they become due, the Company may have to delay expenditures, reduce the scope of its research and development programs, or make significant changes to its operating plan. The accompanying unaudited condensed consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. Intercompany balances and transactions are eliminated in consolidation. Reverse Stock Split On July 16, 2020, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation (the “Amendment”), which became effective on Friday, July 17, 2020, (a) implementing a 1-for-10 presented in these unaudited condensed consolidated financial statements have been retroactively adjusted for the reverse stock split and certain items in the prior period financial statements have been revised to conform to the current presentation. The reverse stock split affected all shares of the Company’s common stock outstanding immediately prior to the effective time of the reverse stock split, as well as the number of shares of common stock available for issuance under the Company’s equity incentive plans. In addition, the reverse stock split effected a reduction in the number of shares of common stock issuable upon the conversion of outstanding convertible notes or upon the exercise of stock options or warrants outstanding. Unaudited Interim Condensed Consolidated Financial Information The accompanying unaudited condensed consolidated financial statements and notes have been prepared in accordance with accounting principles generally accepted in the United States (“US GAAP”), as contained in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (the “Codification” or “ASC”) for interim financial information. In the opinion of management, the interim financial information includes all adjustments of a normal recurring nature necessary for a fair presentation of the results of operations, financial position, and cash flows. The results of operations for the three months ended March 31, 2021, are not necessarily indicative of the results for the full year or the results for any future periods. These unaudited condensed consolidated financial statements should be read in conjunction with the financial statements and notes set forth in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 29, 2021. Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with US GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. Significant estimates include: determination of the fair value of stock-based compensation grants ; the estimate of services and effort expended by third-party research and development service providers used to recognize research and development expense ; and the estimates and assumptions utilized in measuring the fair values of the warrant and derivative liabilities each reporting period.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The accompanying unaudited condensed consolidated financial statements and notes follow the same significant accounting policies as those described in the notes to the audited consolidated financial statements of the Company for the year ended December 31, 2020, except as described below. Revenue Recognition The Company has entered into arrangements involving the sale or license of intellectual property and the provision of other services. When entering into any arrangement involving the sale or license of intellectual property rights and other services, the Company determines whether the arrangement is subject to accounting guidance in ASC 606, Revenue from Contracts with Customers Collaborative Arrangements Analyzing the arrangement to identify performance obligations requires the use of judgment. In arrangements that include the sale or license of intellectual property and other promised services, the Company first identifies if the licenses are distinct from the other promises in the arrangement. If the license is not distinct, the license is combined with other services into a single performance obligation. Factors that are considered in evaluating whether a license is distinct from other promised services include, for example, whether the counterparty can benefit from the license without the promised service on its own or with other readily available resources and whether the promised service is expected to significantly modify or customize the intellectual property. The Company classifies non-refundable upfront payments, milestone payments and royalties received for the sale or license of intellectual property as revenues within its statements of operations because the Company views such activities as being central to its business operations. For the sale of intellectual property that is distinct, fixed consideration and variable consideration are included in the transaction price and recognized in revenue immediately to the extent that it is probable that there would not be a significant reversal of cumulative revenue in the future. For the license of intellectual property that is distinct, fixed and variable consideration (to the extent there will not be a significant reversal in the future) are also recognized immediately in income, except for consideration received in the form of royalty or sales-based milestones, which is recorded when the customer’s subsequent sales or usages occur. If the sale or license of intellectual property is not distinct, revenue is deferred and recognized over the estimated period of the Company’s combined performance obligation. For contractual arrangements that meet the definition of a collaborative arrangement under Topic 808, consideration received for any units-of-account that are outside the scope of Topic 606 are recognized in the statements of operations by considering (i) the nature of the arrangement, (ii) the nature of the Company’s business operations, and (iii) the contractual terms of the arrangement. Basic and Diluted Net Loss per Share of Common Stock The Company calculates net loss per common share in accordance with ASC Earnings Per Share Earnings Per Share, Three Months Ended March 31, 2021 2020 Net loss $ (4,676 ) $ (7,002 ) Dilutive effect of warrant liability (1,323 ) — Net loss allocated to common shares $ (5,999 ) $ (7,002 ) Weighted average common shares outstanding – basic 25,802,700 9,744,577 Dilutive effect of warrant liability 721,220 — Weighted average common shares outstanding – diluted 26,523,920 9,744,577 Net loss per share – diluted $ (0.23 ) $ (0.72 ) The following potentially dilutive shares of common stock have not been included in the computation of diluted net loss per share for the three months ended March 31, 2021 and 2020, as the result would be anti-dilutive: Three Months Ended March 31, 2021 2020 Outstanding stock options 1,371,606 768,354 Outstanding restricted stock units 96,974 85,754 Warrants to purchase common stock associated with June 2016 public offering 421,867 421,867 Warrants to purchase common stock associated with March 2018 public offering – Series 2 798,810 798,810 Warrants to purchase common stock associated with December 2019 Public Offering 4,472,205 4,472,205 Warrants to purchase common stock associated with December 2020 Public Offering - Series 2 6,800,000 — Common stock associated with March 2019 Notes 1,138,200 1,138,200 Warrants to purchase common stock associated with Solar loan agreement 12,243 12,243 Total 15,111,905 7,697,433 Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Financial Instruments – Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity’s Own Equity: Accounting for Convertible Instruments and Contracts in and Entity’s Own Equity Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes: Simplifying the Accounting for Income Taxes simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes , and clarifies certain aspects of the current guidance to promote consistency among reporting entities. This guidance was adopted by the Company in the first quarter of 2021 and it did not have a material impact on its unaudited

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	3 Months Ended
	Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	3 . Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): March 31, 2021 December 31, 2020 Prepaid research and development services $ 1,300 $ 1,535 Prepaid insurance 115 362 Other prepaid expenses 525 19 Other receivables 1,000 2,876 Other current assets 370 373 Total prepaid expenses and other current assets $ 3,310 $ 5,165

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Accrued Expenses	4 . Accrued Expenses Accrued expenses consisted of the following (in thousands): March 31, 2021 December 31, 2020 Accrued research and development expenses $ 647 $ 991 Accrued employee bonus compensation 433 2,190 Other accrued expenses 1,054 960 Total accrued expenses $ 2,134 $ 4,141

Borrowings

Borrowings	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Borrowings	5 . Borrowings April 2020 Note Purchase Agreement On April 9, 2020, the Company entered into the April 2020 Note Purchase Agreement with Puissance Life Science Opportunities Fund VI (“Puissance”) and issued and sold to Puissance $10.0 million aggregate principal amount of its April 2020 Notes, resulting in net proceeds of approximately $9.5 million after deducting $0.5 million for an advisory fee and other issuance costs. At December 31, 2020, the fair value of the April 2020 Notes was $ In January 2021, Puissance converted the remaining $6.0 million of the April 2020 Notes for 959,080 shares of common stock. Upon conversion of the $6.0 million of the April 2020 Notes, the Company recognized a $2.7 million extinguishment loss which represents the difference between the total net carrying amount of the convertible debt and derivative liability of $4.8 million and the fair value of the consideration issued of $7.5 million. March 2019 Note Purchase Agreement On March 7, 2019, the Company entered into a Senior Convertible Note Purchase Agreement (the “March 2019 Note Purchase Agreement”) with Puissance. Pursuant to the March 2019 Note Purchase Agreement, on March 7, 2019, the Company issued and sold to Puissance $16.0 million aggregate principal amount of its 6.0% Senior Convertible Notes due 2025 (“March 2019 Notes”), resulting in $14.7 million in net proceeds after deducting $1.3 million for an advisory fee and other issuance costs. As of March 31, 2021, the Company’s March 2019 Notes consists of the convertible debt balance of $9.6 million, presented net of the unamortized debt issuance costs allocated to the convertible debt of $0.4 million, and the bifurcated embedded conversion option derivative liability of $2.6 million. In connection with the Company’s issuance of its March 2019 Notes, the Company bifurcated the embedded conversion option, inclusive of the interest make-whole provision and make-whole fundamental change provision, and recorded the embedded conversion option as a long-term derivative liability in the Company’s balance sheet in accordance with ASC 815, Derivatives and Hedging The Company estimated the fair value of the convertible debt and derivative liability for the March 2019 Notes using a binomial lattice valuation model and Level 3 inputs. At both March 31, 2021 and December 31, 2020, the fair value of the convertible debt and derivative liability for the March 2019 Notes is $ 12.9 million The March 2019 Notes were issued and sold for cash at a purchase price equal to 100% of their principal amount, in reliance on the exemption from registration The holder of the March 2019 Notes may convert their March 2019 Notes at their option at any time prior to the close of business on the business day immediately preceding March 15, 2025 into shares of the Company’s common stock. The initial conversion rate is 73.9096 shares of common stock per $1,000 principal amount of March 2019 Notes, which is equivalent to an initial conversion price of approximately $13.53 and is subject to adjustment in certain events described in the March 2019 Note Purchase Agreement. The Holder upon conversion may also be entitled to receive, under certain circumstances, an interest make-whole payment payable in shares of common stock. In addition, following certain corporate events that occur prior to the maturity date, the Company will, in certain circumstances, increase the conversion rate if the holder elects to convert its March 2019 Notes in connection with such a corporate event. Subject to adjustment in the conversion rate, the number of shares that the Company may deliver in connection with a conversion of the March 2019 Notes, including those delivered in connection with an interest make-whole payment, will not exceed a cap of 81 shares of common stock per $1,000 principal amount of the March 2019 Notes. On or after March 15, 2022, the Company has the right, at its election, to redeem all or any portion of the March 2019 Notes not previously converted if the last reported sale price per share of common stock exceeds 130% of the conversion price on each of at least 20 trading days (whether or not consecutive) during the 30 consecutive trading days ending on, and including, the trading day immediately before the date the Company sends the related redemption notice. The redemption price will be 100% of the principal amount of the March 2019 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. If a “fundamental change” (as defined in the March 2019 Note Purchase Agreement) occurs, then, subject to certain exceptions, the Company must offer to repurchase the March 2019 Notes for cash at a repurchase price of 100% of the principal amount of the March 2019 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the repurchase date.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	6 . Commitments and Contingencies Leases On March 1, 2018, the Company entered into a long-term lease agreement for approximately 19,275 square feet of office space in Jersey City, New Jersey, that the Company identified as an operating lease under ASC 842 (the “Lease”). The lease term is eleven years from August 1, 2018, the commencement date, with total lease payments of $7.3 million over the lease term. The Company has the option to renew for two consecutive five-year in the accompanying unaudited condensed consolidated balance sheets . The consideration in the Lease allocated to the single lease component includes the fixed payments for the right to use the office space as well as common area maintenance. The Lease also contains costs associated with certain expense escalation, property taxes, insurance, parking, and utilities which are all considered variable payments and are excluded from the operating lease liability. The incremental borrowing rate utilized approximated the prevailing market interest rate the Company would incur to borrow a similar amount equal to the total Lease payments on a collateralized basis over the term of the Lease. The following table summarizes certain quantitative information associated with the amounts recognized in the unaudited condensed consolidated financial statements for the Lease (dollars in thousands): Three Months Ended March 31, 2021 Three Months Ended March 31, 2020 Operating lease cost $ 166 $ 166 Variable lease cost (2 ) 21 Total operating lease expense $ 164 $ 187 Cash paid for amounts included in the measurement of operating lease liability $ 170 $ 167 March 31, 2021 March 31, 2020 Remaining Lease term (years) 8.34 9.34 Discount rate 15 % 15 % Future minimum lease payments for the Lease as of March 31, 2021 are as follows (in thousands): March 31, 2021 2021 $ 347 2022 527 2023 715 2024 730 2025 744 Thereafter 2,789 Total $ 5,852 The presentations of the operating lease liability as of March 31, 2021 are as follows (in thousands): March 31, 2021 Present value of future minimum lease payments $ 3,272 Operating lease liability, current portion $ 57 Operating lease liability, long-term portion 3,215 Total operating lease liability $ 3,272 Difference between future minimum lease payments and discounted cash flows $ 2,580 License Arrangement with Potential Future Expenditures As of March 31, 2021, the Company had a license arrangement with Merck Sharp & Dohme Corp., or Merck, as amended, that involves potential future expenditures. Under the license arrangement, executed in May 2013, the Company exclusively licensed from Merck its rights to ibrexafungerp in the field of human health. In January 2014, Merck assigned the patents related to ibrexafungerp that it had exclusively licensed to the Company. Ibrexafungerp is the Company's lead product candidate. Pursuant to the terms of the license agreement, Merck was originally eligible to receive milestone payments from the Company that could total $19.0 million upon occurrence of specific events, including initiation of a Phase 3 clinical study, new drug application, and marketing approvals in each of the U.S., major European markets, and Japan. In addition, Merck is eligible to receive tiered royalties from the Company based on a percentage of worldwide net sales of ibrexafungerp. The aggregate royalties are mid- to high-single digits. In December 2014, the Company and Merck entered into an amendment to the license agreement that deferred the remittance of a milestone payment due to Merck, such that no amount would be due upon initiation of the first Phase 2 clinical trial of a product containing the ibrexafungerp compound (the “Deferred Milestone”). The amendment also increased, in an amount equal to the Deferred Milestone, the milestone payment that would be due upon initiation of the first Phase 3 clinical trial of a product containing the ibrexafungerp compound. In December 2016 and January 2018, the Company entered into second and third amendments to the license agreement with Merck which clarified what would constitute the initiation of a Phase 3 clinical trial for the purpose of milestone payment. In January 2019, a milestone payment became due to Merck as a result of the initiation of the VANISH Phase 3 VVC program and was paid in March 2019. On December 2, 2020, the Company entered into a fourth amendment to the license agreement with Merck. The amendment eliminates two cash milestone payments that the Company would have paid to Merck upon the first filing of an NDA, triggered by the FDA acceptance for filing of the Company’s NDA for ibrexafungerp for the treatment of VVC, and first marketing approval in the U.S., anticipated in June 2021 for the Company’s NDA for ibrexafungerp for the treatment of VVC. Such cash milestone payments would have been creditable against future royalties owed to Merck on net sales of ibrexafungerp. With the amendment, these milestones will not be paid in cash and, accordingly, credits will not accrue. Pursuant to the amendment, the Company will also forfeit the credits against future royalties that it had accrued from a prior milestone payment already paid to Merck. All other key terms of the license agreement are unchanged. Clinical Development Arrangements The Company has entered into, and expects to continue to enter into, contracts in the normal course of business with various third parties who support its clinical trials, preclinical research studies, and other services related to its development activities. The scope of the services under these agreements can generally be modified at any time, and the agreement can be terminated by either party after a period of notice and receipt of written notice.

Stockholders_ Equity

Stockholders’ Equity	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Stockholders’ Equity	7 . Stockholders’ Equity Authorized, Issued, and Outstanding Common Stock The Company’s authorized common stock has a par value of $0.001 per share and consists of 100,000,000 shares as of March 31, 2021, and December 31, 2020; 20,625,637 and 19,663,698 shares were issued and outstanding at March 31, 2021, and December 31, 2020, respectively. On July 16, 2020, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation (the “Amendment”), which became effective on Friday, July 17, 2020, (a) implementing a 1-for- 10 The following table summarizes common stock share activity for the three months ended March 31, 2021 and 2020 (dollars in thousands): Three Months Ended March 31, 2021 Shares of Common Stock Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Balance, December 31, 2020 19,663,698 $ 20 $ 349,351 $ (326,613 ) $ 22,758 Net loss — — — (4,676 ) (4,676 ) Stock-based compensation expense — — 398 — 398 Common stock issued for conversion of April 2020 Notes 959,080 1 7,452 — 7,453 Common stock issued through employee stock purchase plan 2,184 — 6 — 6 Common stock issued for vested restricted stock units 675 — (15 ) — (15 ) Balance, March 31, 2021 20,625,637 $ 21 $ 357,192 $ (331,289 ) $ 25,924 Three Months Ended March 31, 2020 Shares of Common Stock Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Balance, December 31, 2019 9,741,372 $ 10 $ 284,313 $ (271,428 ) $ 12,895 Net loss — — — (7,002 ) (7,002 ) Stock-based compensation expense — — 410 — 410 Common stock issued through employee stock purchase plan 2,215 — 18 — 18 Common stock issued, net of expenses 28,527 — 207 — 207 Common stock issued for vested restricted stock units 15,490 — (73 ) — (73 ) Balance, March 31, 2020 9,787,604 $ 10 $ 284,875 $ (278,430 ) $ 6,455 Shares Reserved for Future Issuance The Company had reserved shares of common stock for future issuance as follows: March 31, 2021 December 31, 2020 Outstanding stock options 1,371,606 830,343 Outstanding restricted stock units 96,974 29,087 Warrants to purchase common stock associated with June 2016 Public Offering 421,867 421,867 Warrants to purchase common stock associated with March 2018 Public Offering – Series 2 798,810 798,810 Warrants to purchase common stock associated with December 2019 Public Offering 4,472,205 4,472,205 Warrants to purchase common stock associated with December 2020 Public Offering - Series 1 6,800,000 6,800,000 Warrants to purchase common stock associated with December 2020 Public Offering - Series 2 6,800,000 6,800,000 Prefunded warrants to purchase common stock associated with December 2020 Public Offering 5,260,000 5,260,000 Warrants to purchase common stock associated with Solar loan agreement 12,243 12,243 For possible future issuance for the conversion of the March 2019 Notes 1,138,200 1,138,200 For possible future issuance for the conversion of the April 2020 Notes — 1,299,790 For possible future issuance under 2014 Equity Incentive Plan (Note 9) 318,097 146,488 For possible future issuance under Employee Stock Purchase Plan 6,652 5,895 For possible future issuance under 2015 Inducement Award Plan (Note 9) 14,050 14,050 Total common shares reserved for future issuance 27,510,704 28,028,978 Common Stock Purchase Agreement On April 10, 2020, the Company entered into the Common Stock Purchase Agreement with Aspire Capital pursuant to which the Company has the right to sell to Aspire Capital from time to time in its sole discretion up to $20.0 million in shares of the Company’s common stock over the next 30 months, subject to certain limitations and conditions set forth in the Common Stock Purchase Agreement. The aggregate number of shares that we can sell to Aspire Capital under the Common Stock Purchase Agreement may in no case exceed 1,956,547 shares of the Company’s common stock (which is equal to approximately 19.99% of the common stock outstanding on the date of the Common Stock Purchase Agreement), including the 70,910 commitment shares (the Exchange Cap), unless either (a) shareholder approval is obtained to issue more, in which case the Exchange Cap will not apply, or (b) the average purchase price of all shares sold under the Common Stock Purchase Agreement exceeds $8.461; provided that at no time shall Aspire Capital (together with its affiliates) beneficially own more than 19.99% of the Company’s common stock. During the three months ended March 31, 2021 and 2020, the Company did not sell any shares of its common stock under the Common Stock Purchase Agreement. Convertible Debt and Derivative Liabilities In connection with the Company’s issuances of its April 2020 Notes and March 2019 Notes, the Company bifurcated the embedded conversion options, inclusive of the interest make-whole provisions and make-whole fundamental change provisions, and recorded the embedded conversion options as long-term derivative liabilities in the Company’s balance sheet in accordance with ASC 815, Derivatives and Hedging Warrants Associated with June 2016 , March 2018 , December 2019 , and December 2020 Public Offerings The outstanding warrants associated with the June 2016, March 2018, December 2019, and December 2020 public offerings contain a provision where the warrant holder has the option to receive cash, equal to the Black-Scholes fair value of the remaining unexercised portion of the warrant, as cash settlement in the event that there is a fundamental transaction (contractually defined to include various merger, acquisition or stock transfer activities). Due to this provision, ASC 480, Distinguishing Liabilities from Equity, Warrant Associated with Solar Loan Agreement On the closing date of the Company’s previous loan agreement with Solar, pursuant to the loan agreement the Company issued to Solar the warrant to purchase an aggregate of up to 12,243 shares of the Company’s common stock at an exercise price of $36.754 per share. The warrant will expire five years from the date of the grant. The warrant was classified as equity and recorded at its relative fair value at issuance in the stockholders’ equity section of the balance sheet.

Stock-based Compensation

Stock-based Compensation	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Compensation	8 . Stock-based Compensation Pursuant to the terms of the Company’s 2014 Equity Incentive Plan (“2014 Plan”), on January 1, 2021 and 2020, the Company automatically added 786,547 and 389,650 shares to the total number shares of common stock available for future issuance under the 2014 Plan, respectively. As of March 31, 2021, there were 318,097 shares of common stock available for future issuance under the 2014 Plan. As of March 31, 2021, there were 14,050 shares of common stock available for future issuance under the Company’s 2015 Inducement Award Plan (“2015 Plan”). During the three months ended March 31, 2021 and 2020, there were zero and 17,500 granted options of the Company’s common stock under the 2015 Plan, respectively. On April 30, 2021, the Company’s board of directors amended the 2015 Plan, and the share reserve for the 2015 Plan was increased from 90,000 to 500,000 shares of common stock. The activity for the Company’s 2009 Stock Option Plan, 2014 Plan, and 2015 Plan, for the three months ended March 31, 2021, is summarized as follows: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value ($000) Outstanding — December 31, 2020 830,343 $ 21.52 7.71 $ 96 Granted 545,450 $ 7.57 Forfeited/Cancelled (4,187 ) $ 8.48 Outstanding — March 31, 2021 1,371,606 $ 16.01 8.33 $ 355 Exercisable — March 31, 2021 500,625 $ 29.27 6.72 $ 37 Vested or expected to vest — March 31, 2021 1,371,606 $ 16.01 8.33 $ 355 Restricted stock unit (“RSU”) activity under the 2014 Plan and 2015 Plan for the three months ended March 31, 2021, is summarized as follows: Number of Shares Weighted Average Grant Date Fair Value Per Share Non-vested at December 31, 2020 29,087 $ 9.52 Granted 73,675 $ 7.55 Vested (5,788 ) $ 10.68 Non-vested at March 31, 2021 96,974 $ 7.95 The fair value of RSUs is based on the market price of the Company’s common stock on the date of grant. RSUs generally vest 25% annually over a four-year Upon vesting, the RSUs are net share settled to cover the required withholding tax with the remaining shares issued to the holder. The Company recognizes compensation expense for such awards ratably over the corresponding vesting period. Compensation Cost The compensation cost that has been charged against income for stock awards under the 2014 Plan and the 2015 Plan was $0.4 million for both the three months ended March 31, 2021 and 2020. The total income tax benefit recognized in the statements of operations for share-based compensation arrangements was zero for each of the three months ended March 31, 2021 and 2020. Stock-based compensation expense related to stock options is included in the following line items in the accompanying unaudited condensed consolidated statements of operations (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 126 $ 136 Selling, general and administrative 272 274 Total $ 398 $ 410

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	9 . Fair Value Measurements The carrying amounts of certain financial instruments, including cash and cash equivalents, restricted cash, accounts receivable, prepaid expenses and other current assets, accounts payable, and accrued expenses approximate their respective fair values due to the short-term nature of such instruments. Assets and Liabilities Measured at Fair Value on a Recurring Basis The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level in which to classify them for each reporting period. This determination requires significant judgments to be made. The following table summarizes the conclusions reached as of March 31, 2021 and December 31, 2020 for financial instruments measured at fair value on a recurring basis (in thousands): Fair Value Hierarchy Classification Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) March 31, 2021 Cash $ 236 $ 236 — — Restricted cash 273 273 — — Money market funds 91,775 91,775 — — Total assets $ 92,284 $ 92,284 — — Warrant liabilities $ 49,860 — — $ 49,860 Derivative liability 2,618 — — 2,618 Total liabilities $ 52,478 — — $ 52,478 December 31, 2020 Cash $ 117 $ 117 — — Restricted cash 273 273 — — Money market funds 92,924 92,924 — — Total assets $ 93,314 $ 93,314 — — Warrant liabilities $ 51,156 — — $ 51,156 Derivative liabilities 5,954 — — 5,954 Total liabilities $ 57,110 — — $ 57,110 The Company measures cash equivalents at fair value on a recurring basis. The fair value of cash equivalents is determined based on “Level 1” inputs, which consist of quoted prices in active markets for identical assets. Level 3 financial liabilities consist of the warrant liabilities for which there is no current market such that the determination of fair value requires significant judgment or estimation. Changes in fair value measurements categorized within Level 3 of the fair value hierarchy are analyzed each period based on changes in estimates or assumptions and recorded as appropriate. The Company uses the Black-Scholes option valuation model to value the Level 3 warrant liabilities at inception and on subsequent valuation dates. This model incorporates transaction details such as the Company’s stock price, contractual terms, maturity, risk free rates, as well as volatility. The unobservable input for all of the Level 3 warrant liabilities includes volatility. The historical volatility of the Company, using its closing common stock prices, is utilized to reflect future volatility over the expected term of the warrants. At March 31, 2021, the range and weighted average of the Level 3 volatilities utilized in the Black-Scholes model to fair value the warrant liabilities were 69.6% to 82.5% and 77.6%, respectively. Additionally, the expected term associated with the December 2019 Public Offering warrants is an unobservable unit given that the expiration of the warrants is the earlier of (i) such date that is six months after the Company publicly announces the approval from the U.S. Food and Drug Administration for ibrexafungerp for the treatment of vulvovaginal candidiasis and (ii) June 12, 2023. 0.66 to 2.2 years The Company uses the binomial lattice valuation model to value the Level 3 derivative liabilit ies at inception and on subsequent valuation dates. This model incorporates transaction details such as the Company’s stock price, contractual terms, dividend yield, risk-free rate, historical volatility, credit rating, market credit spread, and estimated effective yield. The unobservable inputs associated with the Level 3 derivative liabilit ies are adjusted equity volatility, market credit spread, and estimated yield. As of March 31, 2021 , these inputs were 61.5 %, basis points, and 15.1 %, respectively. The senior convertible notes are initially fair valued using the binomial lattice model and with the straight debt fair value calculated using the discounted cash flow method. The discount for lack of marketability, 7.1 % as of March 31, 2021 , is applied to the value of the March 2019 Notes . The residual difference represents the fair value of the embedded derivative liabilit ies and the fair value of the embedded derivative liabilit ies are reassessed using the binomial lattice valuation model on a quarterly basis . A reconciliation of the beginning and ending balances for liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) is as follows (in thousands): Warrant Liabilities Balance – December 31, 2020 $ 51,156 Gain adjustment to fair value (1,296 ) Balance – March 31, 2021 $ 49,860 Derivative Liabilities Balance – December 31, 2020 $ 5,954 Adjustment for conversion of April 2020 Notes (3,426 ) Gain adjustment to fair value 90 Balance – March 31, 2021 $ 2,618

License Agreement Revenue

License Agreement Revenue	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
License Agreement Revenue	10. License Agreement Revenue In February 2021, the Company entered into an Exclusive License and Collaboration Agreement (the “Agreement”) with Hansoh (Shanghai) Health Technology Co., Ltd., and Jiangsu Hansoh Pharmaceutical Group Company Limited (collectively, “Hansoh”), pursuant to which the Company granted to Hansoh an exclusive license to research, develop and commercialize ibrexafungerp in the Greater China region, including mainland China, Hong Kong, Macau, and Taiwan (the “Territory”). The Company also granted to Hansoh a non-exclusive license to manufacture ibrexafungerp solely for development and commercialization in the Territory. Under the terms of the Agreement, Hansoh shall be responsible for the development, regulatory approval and commercialization of ibrexafungerp in the Territory. Pursuant to the terms of the Agreement, the Company received as consideration for the licenses a nonrefundable upfront cash payment of $10.0 million and is entitled to an additional payment that was payable upon the transfer of certain data related to the manufacturing license. In addition, the Company will also be eligible to receive up to $110.0 million in potential development and commercial milestones. In addition, during the term of the licensing agreement, the Company is entitled to low double-digit royalties on net product sales. The obligation to pay royalties with respect to sales in a specified region will continue until the later of the date of expiration of all intellectual property and regulatory exclusivity for the product in the region and ten years from the first commercial sale, unless earlier terminated by Hansoh with advanced notice for convenience or under other specified circumstances. The Company is also eligible to receive a milestone related to the successful completion of a manufacturing batch The Company evaluated the Agreement and concluded that it was subject to ASC 606 as the Company viewed the Agreement as a contract with a customer as the activities were central to its business operations. As such, the Company assessed the terms of the Agreement and identified one performance obligation for the licenses to research, develop, manufacture and commercialize ibrexafungerp in the Territory, including the underlying know-how related to such licenses. The Company also evaluated options for additional goods and services included in the Agreement related to (1) optional technical assistance related to development, regulatory or manufacturing activities and (2) an optional supply agreement for ibrexafungerp. Such options for additional goods or services were not considered to contain material rights as pricing approximated standalone selling prices and therefore the Company concluded that such options did not represent performance obligations and will be accounted for as separate transactions if and when they occur in the future. The Company determined that the transaction price of $12.1 million included the fixed upfront cash payment of $10.0 million, an additional amount that was payable upon the transfer of certain data related to the manufacturing license, and $1.1 million related to withholding tax obligations that Hansoh remitted on behalf of the Company. The remaining amounts related to the successful completion of a manufacturing batch by Hansoh and potential development milestones represent variable consideration and were constrained as it was concluded that it was not probable that a significant reversal in cumulative revenue recognized will not occur and therefore not included in the transaction price as of March 31, 2021. Potential commercial milestones and royalties on net product sales will be recognized in the same period that the underlying net product sales occur as they were determined to relate to the license. The transaction price was recorded in revenue during the quarter March 31, 2021 at a point in time upon control of the license transferring to Hansoh . The Company will reevaluate the transaction price at the end of each reporting period as uncertain events or resolved, or as other changes in circumstances occur. Additionally, pursuant to the Agreement, both the Company and Hansoh agreed to make reasonable efforts to account for applicable taxes, fees, duties, levies, or similar amounts imposed on net income, franchise taxes and profits arising directly or indirectly from the activities of the Agreement. To the extent Hansoh is required by applicable laws to withhold or deduct any tax on any payment to the Company, Hansoh agreed to make certain increases on payments to the Company to ensure that the Company receives a sum equal to what the Company would have received had there been no deduction or withholding. As a result, the Company has recorded revenue and tax withholding expense primarily associated with the up-front payment received by the Company on a gross basis. For the three months ended March 31, 2021, the Company recognized $1.1 million in revenue and $1.1 million in income tax expense to account for the tax withholding expense primarily on the $10.0 million up-front that the Company is responsible to remit under applicable tax law. In July 2016, the Company entered into an asset purchase agreement with UK-based Cypralis Limited (or "Cypralis"), a life sciences company, for the sale of its cyclophilin inhibitor assets. Cypralis also acquired all patents, patent applications and know-how related to the acquired portfolio. In connection with the asset purchase agreement, the Company is eligible to receive milestone payments upon the successful progression of Cypralis clinical candidates into later stage clinical studies and royalties payable upon product commercialization. The Company retains the right to repurchase the portfolio assets from Cypralis if abandoned or deprioritized. For the three months ended March 31, 2021, there was no revenue recognized associated with this agreement given the variable consideration associated with the sale of intellectual property to Cypralis was fully constrained as of March 31, 2021. Additionally, in October 2014 the Company entered into a license agreement with Waterstone Pharmaceutical HK Limited (or “Waterstone”) and granted Waterstone an exclusive, worldwide license to develop and commercialize certain non-strategic compounds. The Company is entitled to receive potential milestones and royalties from Waterstone; however, there was no revenue recognized by the Company associated with this agreement given the variable consideration was fully constrained as of March 31, 2021.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	1 1 . Subsequent Events In May 2021, the Company entered into an agreement with a third party to sell a portion of its unused New Jersey net operating losses (NOLs) for approximately $4.2 million. In May 2021, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with Hercules Capital, Inc. (“Hercules”), as administrative agent and collateral agent (in such capacity, the “Agent”) and a lender, and Silicon Valley Bank, as a lender (“SVB,” and collectively with Hercules, the “Lenders”) for an aggregate principal amount of $60.0 million (the “Term Loan”). Pursuant to the Loan Agreement, the Term Loan is available to the Company in four tranches, subject to certain terms and conditions. Under the terms of the Loan Agreement, the Company received an initial tranche of $20.0 million from the Lenders on the Closing Date. The second tranche of the Term Loan, consisting of up to an additional $10.0 million, will become available to the Company upon receipt of approval from the Food and Drug Administration of ibrexafungerp for the treatment of vaginal yeast infections (the “First Performance Milestone”) and will be available, if specified conditions are met, during the period beginning on June 1, 2021 through June 30, 2022. The third tranche of the Term Loan, consisting of an additional $5.0 million, will be available to the Company upon (a) the First Performance Milestone and (b) the achievement of the primary endpoint from the Phase 3 study of ibrexafungerp in patients with recurrent vulvovaginal candidiasis, and will be available, if specified conditions are met, from September 30, 2021 through June 30, 2022. The fourth tranche of the Term Loan, consisting of up to an additional $25.0 million, will be available to the Company from January 1, 2022 through December 31, 2023 in $5.0 million increments, subject to certain terms and conditions, including in maintaining a ratio of total outstanding Term Loan principal to net product revenues for ibrexafungerp below a certain specified level for a given draw period. The Term Loan will mature on March 3, 2025 (the “Maturity Date”); provided that, the Maturity Date shall be automatically extended to May 1, 2025 subject to the occurrence of certain conditions set forth in the Loan Agreement. The Term Loan bears interest at a variable annual rate equal to the greater of (a) 9.05% and (b) the Prime Rate (as reported in the Wall Street Journal) plus 5.80% (the “Interest Rate”). The Company may make payments of interest only through November 1, 2023, which may be extended to May 1, 2024 upon the achievement of the First Performance Milestone prior to November 1, 2023, and which is further extendable in quarterly increments until the Maturity Date, subject to continued compliance with the financial covenant of the Loan Agreement (the “interest-only period”). After the interest-only period, the principal balance and related interest will be required to be repaid in equal monthly installments and continuing until the Maturity Date. The Loan Agreement contains customary closing fees, prepayment fees and provisions, events of default, and representations, warranties and covenants, including a financial covenant requiring the Company to maintain certain levels of trailing three-month net product revenue solely from the sale of ibrexafungerp commencing on June 30, 2022. The financial covenant will be waived at any time in which the Company maintains unrestricted and unencumbered cash in accounts maintained with SVB equal to at least 50.0% of the total outstanding Term Loan principal amount, subject to certain requirements. In connection with the entry into the Loan Agreement, the Company issued to each of Hercules and SVB a warrant (collectively, the “Warrants”) to purchase shares of SCYNEXIS’s common stock, par value $ 0.001 per share (the “Shares”). The amount of shares that may be purchased for the Warrants, collectively between Hercules and SVB , will not exceed 0.04 multiplied by the aggregate amount of the term loan advances, divided by the exercise price of the Warrants .

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basic and Diluted Net Loss per Share of Common Stock	Basic and Diluted Net Loss per Share of Common Stock The Company calculates net loss per common share in accordance with ASC Earnings Per Share Earnings Per Share, Three Months Ended March 31, 2021 2020 Net loss $ (4,676 ) $ (7,002 ) Dilutive effect of warrant liability (1,323 ) — Net loss allocated to common shares $ (5,999 ) $ (7,002 ) Weighted average common shares outstanding – basic 25,802,700 9,744,577 Dilutive effect of warrant liability 721,220 — Weighted average common shares outstanding – diluted 26,523,920 9,744,577 Net loss per share – diluted $ (0.23 ) $ (0.72 ) The following potentially dilutive shares of common stock have not been included in the computation of diluted net loss per share for the three months ended March 31, 2021 and 2020, as the result would be anti-dilutive: Three Months Ended March 31, 2021 2020 Outstanding stock options 1,371,606 768,354 Outstanding restricted stock units 96,974 85,754 Warrants to purchase common stock associated with June 2016 public offering 421,867 421,867 Warrants to purchase common stock associated with March 2018 public offering – Series 2 798,810 798,810 Warrants to purchase common stock associated with December 2019 Public Offering 4,472,205 4,472,205 Warrants to purchase common stock associated with December 2020 Public Offering - Series 2 6,800,000 — Common stock associated with March 2019 Notes 1,138,200 1,138,200 Warrants to purchase common stock associated with Solar loan agreement 12,243 12,243 Total 15,111,905 7,697,433
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Financial Instruments – Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity’s Own Equity: Accounting for Convertible Instruments and Contracts in and Entity’s Own Equity Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes: Simplifying the Accounting for Income Taxes simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes , and clarifies certain aspects of the current guidance to promote consistency among reporting entities. This guidance was adopted by the Company in the first quarter of 2021 and it did not have a material impact on its unaudited

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Schedule of Diluted Net Loss Per Common Share	Diluted net loss per common share for the three months ended March 31, 2021 and 2020 was determined as follows (in thousands, except share and per share amounts): Three Months Ended March 31, 2021 2020 Net loss $ (4,676 ) $ (7,002 ) Dilutive effect of warrant liability (1,323 ) — Net loss allocated to common shares $ (5,999 ) $ (7,002 ) Weighted average common shares outstanding – basic 25,802,700 9,744,577 Dilutive effect of warrant liability 721,220 — Weighted average common shares outstanding – diluted 26,523,920 9,744,577 Net loss per share – diluted $ (0.23 ) $ (0.72 )
Summary of Antidilutive Securities Excluded from Computation of Weighted Average Common Stock Outstanding	The following potentially dilutive shares of common stock have not been included in the computation of diluted net loss per share for the three months ended March 31, 2021 and 2020, as the result would be anti-dilutive: Three Months Ended March 31, 2021 2020 Outstanding stock options 1,371,606 768,354 Outstanding restricted stock units 96,974 85,754 Warrants to purchase common stock associated with June 2016 public offering 421,867 421,867 Warrants to purchase common stock associated with March 2018 public offering – Series 2 798,810 798,810 Warrants to purchase common stock associated with December 2019 Public Offering 4,472,205 4,472,205 Warrants to purchase common stock associated with December 2020 Public Offering - Series 2 6,800,000 — Common stock associated with March 2019 Notes 1,138,200 1,138,200 Warrants to purchase common stock associated with Solar loan agreement 12,243 12,243 Total 15,111,905 7,697,433

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	3 Months Ended
	Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): March 31, 2021 December 31, 2020 Prepaid research and development services $ 1,300 $ 1,535 Prepaid insurance 115 362 Other prepaid expenses 525 19 Other receivables 1,000 2,876 Other current assets 370 373 Total prepaid expenses and other current assets $ 3,310 $ 5,165

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consisted of the following (in thousands): March 31, 2021 December 31, 2020 Accrued research and development expenses $ 647 $ 991 Accrued employee bonus compensation 433 2,190 Other accrued expenses 1,054 960 Total accrued expenses $ 2,134 $ 4,141

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Summary of Quantitative Information Associated with Amounts Recognized in Unaudited Condensed Consolidated Financial Statements for Lease	The following table summarizes certain quantitative information associated with the amounts recognized in the unaudited condensed consolidated financial statements for the Lease (dollars in thousands): Three Months Ended March 31, 2021 Three Months Ended March 31, 2020 Operating lease cost $ 166 $ 166 Variable lease cost (2 ) 21 Total operating lease expense $ 164 $ 187 Cash paid for amounts included in the measurement of operating lease liability $ 170 $ 167 March 31, 2021 March 31, 2020 Remaining Lease term (years) 8.34 9.34 Discount rate 15 % 15 %
Future Minimum Lease Payments	Future minimum lease payments for the Lease as of March 31, 2021 are as follows (in thousands): March 31, 2021 2021 $ 347 2022 527 2023 715 2024 730 2025 744 Thereafter 2,789 Total $ 5,852
Presentation of Operating Lease Liability	The presentations of the operating lease liability as of March 31, 2021 are as follows (in thousands): March 31, 2021 Present value of future minimum lease payments $ 3,272 Operating lease liability, current portion $ 57 Operating lease liability, long-term portion 3,215 Total operating lease liability $ 3,272 Difference between future minimum lease payments and discounted cash flows $ 2,580

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Summary of Common Stock Shares Activity	The following table summarizes common stock share activity for the three months ended March 31, 2021 and 2020 (dollars in thousands): Three Months Ended March 31, 2021 Shares of Common Stock Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Balance, December 31, 2020 19,663,698 $ 20 $ 349,351 $ (326,613 ) $ 22,758 Net loss — — — (4,676 ) (4,676 ) Stock-based compensation expense — — 398 — 398 Common stock issued for conversion of April 2020 Notes 959,080 1 7,452 — 7,453 Common stock issued through employee stock purchase plan 2,184 — 6 — 6 Common stock issued for vested restricted stock units 675 — (15 ) — (15 ) Balance, March 31, 2021 20,625,637 $ 21 $ 357,192 $ (331,289 ) $ 25,924 Three Months Ended March 31, 2020 Shares of Common Stock Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Balance, December 31, 2019 9,741,372 $ 10 $ 284,313 $ (271,428 ) $ 12,895 Net loss — — — (7,002 ) (7,002 ) Stock-based compensation expense — — 410 — 410 Common stock issued through employee stock purchase plan 2,215 — 18 — 18 Common stock issued, net of expenses 28,527 — 207 — 207 Common stock issued for vested restricted stock units 15,490 — (73 ) — (73 ) Balance, March 31, 2020 9,787,604 $ 10 $ 284,875 $ (278,430 ) $ 6,455
Common Stock Reserved For Future Issuances	The Company had reserved shares of common stock for future issuance as follows: March 31, 2021 December 31, 2020 Outstanding stock options 1,371,606 830,343 Outstanding restricted stock units 96,974 29,087 Warrants to purchase common stock associated with June 2016 Public Offering 421,867 421,867 Warrants to purchase common stock associated with March 2018 Public Offering – Series 2 798,810 798,810 Warrants to purchase common stock associated with December 2019 Public Offering 4,472,205 4,472,205 Warrants to purchase common stock associated with December 2020 Public Offering - Series 1 6,800,000 6,800,000 Warrants to purchase common stock associated with December 2020 Public Offering - Series 2 6,800,000 6,800,000 Prefunded warrants to purchase common stock associated with December 2020 Public Offering 5,260,000 5,260,000 Warrants to purchase common stock associated with Solar loan agreement 12,243 12,243 For possible future issuance for the conversion of the March 2019 Notes 1,138,200 1,138,200 For possible future issuance for the conversion of the April 2020 Notes — 1,299,790 For possible future issuance under 2014 Equity Incentive Plan (Note 9) 318,097 146,488 For possible future issuance under Employee Stock Purchase Plan 6,652 5,895 For possible future issuance under 2015 Inducement Award Plan (Note 9) 14,050 14,050 Total common shares reserved for future issuance 27,510,704 28,028,978

Stock-based Compensation (Table

Stock-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Share-based Compensation, Stock Options, Activity	The activity for the Company’s 2009 Stock Option Plan, 2014 Plan, and 2015 Plan, for the three months ended March 31, 2021, is summarized as follows: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value ($000) Outstanding — December 31, 2020 830,343 $ 21.52 7.71 $ 96 Granted 545,450 $ 7.57 Forfeited/Cancelled (4,187 ) $ 8.48 Outstanding — March 31, 2021 1,371,606 $ 16.01 8.33 $ 355 Exercisable — March 31, 2021 500,625 $ 29.27 6.72 $ 37 Vested or expected to vest — March 31, 2021 1,371,606 $ 16.01 8.33 $ 355
Schedule of Restricted Stock Units ("RSU") Activity	Restricted stock unit (“RSU”) activity under the 2014 Plan and 2015 Plan for the three months ended March 31, 2021, is summarized as follows: Number of Shares Weighted Average Grant Date Fair Value Per Share Non-vested at December 31, 2020 29,087 $ 9.52 Granted 73,675 $ 7.55 Vested (5,788 ) $ 10.68 Non-vested at March 31, 2021 96,974 $ 7.95
Stock-Based Compensation Expense Related to Stock Options	Stock-based compensation expense related to stock options is included in the following line items in the accompanying unaudited condensed consolidated statements of operations (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 126 $ 136 Selling, general and administrative 272 274 Total $ 398 $ 410

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Financial Instruments Measured on a Recurring Basis	The following table summarizes the conclusions reached as of March 31, 2021 and December 31, 2020 for financial instruments measured at fair value on a recurring basis (in thousands): Fair Value Hierarchy Classification Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) March 31, 2021 Cash $ 236 $ 236 — — Restricted cash 273 273 — — Money market funds 91,775 91,775 — — Total assets $ 92,284 $ 92,284 — — Warrant liabilities $ 49,860 — — $ 49,860 Derivative liability 2,618 — — 2,618 Total liabilities $ 52,478 — — $ 52,478 December 31, 2020 Cash $ 117 $ 117 — — Restricted cash 273 273 — — Money market funds 92,924 92,924 — — Total assets $ 93,314 $ 93,314 — — Warrant liabilities $ 51,156 — — $ 51,156 Derivative liabilities 5,954 — — 5,954 Total liabilities $ 57,110 — — $ 57,110
Summary of Reconciliation of Beginning and Ending Balances for Liabilities Measured at Fair Value on Recurring Basis	A reconciliation of the beginning and ending balances for liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) is as follows (in thousands): Warrant Liabilities Balance – December 31, 2020 $ 51,156 Gain adjustment to fair value (1,296 ) Balance – March 31, 2021 $ 49,860 Derivative Liabilities Balance – December 31, 2020 $ 5,954 Adjustment for conversion of April 2020 Notes (3,426 ) Gain adjustment to fair value 90 Balance – March 31, 2021 $ 2,618

Description of Business and B_2

Description of Business and Basis of Preparation - Additional Information (Detail) $ in Thousands	Jul. 16, 2020shares	Mar. 31, 2021USD ($)shares	Dec. 31, 2020USD ($)shares	Jul. 17, 2020shares
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit		$ (331,289)	$ (326,613)
Cash and cash equivalents		$ 92,011	$ 93,041
Reverse stock split, ratio	0.1
Common stock, shares authorized (in shares) | shares	250,000,000	100,000,000	100,000,000	100,000,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	Mar. 31, 2021shares
ASU 2019-12
Subsidiary Sale Of Stock [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Mar. 31, 2021
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect	true
December 2020 Public Offering | Pre-funded Warrants
Subsidiary Sale Of Stock [Line Items]
Number of warrants issued to purchase common stock (in shares)	5,260,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accounting Policies [Abstract]
Net loss	$ (4,676)	$ (7,002)
Dilutive effect of warrant liability	(1,323)	0
Net loss allocated to common shares	$ (5,999)	$ (7,002)
Weighted average common shares outstanding – basic	25,802,700	9,744,577
Dilutive effect of warrant liability	721,220	0
Weighted average common shares outstanding – diluted	26,523,920	9,744,577
Net loss per share – diluted	$ (0.23)	$ (0.72)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Shares (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	15,111,905	7,697,433
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,371,606	768,354
Outstanding restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	96,974	85,754
Warrants to purchase common stock associated with June 2016 Public Offering | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	421,867	421,867
March 2018 Public Offering Series 2 | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	798,810	798,810
December 2019 Public Offering | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	4,472,205	4,472,205
December 2020 Public Offering Series 2 | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	6,800,000	0
Common stock associated with March 2019 Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,138,200	1,138,200
Warrants to purchase common stock associated with Solar loan agreement | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	12,243	12,243

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid research and development services	$ 1,300	$ 1,535
Prepaid insurance	115	362
Other prepaid expenses	525	19
Other receivables	1,000	2,876
Other current assets	370	373
Total prepaid expenses and other current assets	$ 3,310	$ 5,165

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Accrued research and development expenses	$ 647	$ 991
Accrued employee bonus compensation	433	2,190
Other accrued expenses	1,054	960
Total accrued expenses	$ 2,134	$ 4,141

Borrowings - Additional Informa

Borrowings - Additional Information (Details)	Apr. 09, 2020USD ($)	Mar. 07, 2019USD ($)d$ / shares	Jan. 31, 2021USD ($)shares	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Loss on extinguishment of debt				$ 2,725,000	$ 0
Net carrying amount of convertible debt and derivative liability				12,226,000		$ 16,516,000
Amortization of debt issuance costs and discount				256,000	278,000
April 2020 Note Purchase Agreement
Debt Instrument [Line Items]
Date of issuance and sale of notes	Apr. 9, 2020
Face amount	$ 10,000,000
Proceeds from debt, net of issuance costs	9,500,000
Payment of debt issuance costs	$ 500,000
Fair value of notes						7,400,000
Conversion of convertible note, amount			$ 6,000,000
Conversion of convertible note exchanged for shares | shares			959,080
Loss on extinguishment of debt			$ 2,700,000
Net carrying amount of convertible debt and derivative liability			4,800,000
Fair value of the consideration issued			$ 7,500,000
Senior Convertible Note Purchase Agreement
Debt Instrument [Line Items]
Date of issuance and sale of notes		Mar. 7, 2019
Face amount		$ 16,000,000
Proceeds from debt, net of issuance costs		14,700,000
Payment of debt issuance costs		$ 1,300,000
Senior convertible notes				9,600,000
Unamortized debt issuance cost				400,000
Bifurcated embedded conversion option derivative liability				2,600,000
Derivative, fair value				7,000,000
Gain (loss) on fair value adjustment of derivative liability				42,000	700,000
Amortization of debt issuance costs and discount				300,000	$ 300,000
Fair value of convertible debt and derivative liability				$ 12,900,000		$ 12,900,000
Purchase price as percentage of principal amount		100.00%
Interest rate		6.00%
Payment terms				The March 2019 Notes bear interest at a rate of 6.0% per annum payable semiannually in arrears on March 15 and September 15 of each year, beginning September 15, 2019. The March 2019 Notes will mature on March 15, 2025, unless earlier converted, redeemed or repurchased.
Notes maturity date		Mar. 15, 2025
Notes maturity description				The March 2019 Notes will mature on March 15, 2025, unless earlier converted, redeemed or repurchased
Conversion terms				holder of the March 2019 Notes may convert their March 2019 Notes at their option at any time prior to the close of business on the business day immediately preceding March 15, 2025 into shares of the Company’s common stock.
Conversion rate, number of shares to be issued per $1000 of principal (in shares)		73.9096
Principal amount of notes used as the denominator for conversion into notes		$ 1,000
Initial conversion price of notes | $ / shares		$ 13.53
Conversion rate, number of shares to be issued per $1000 of principal (in shares) after adjustment to certain events		81
Principal amount of notes used as the denominator for conversion into notes after adjustment of certain events		$ 1,000
Convertible notes, redemption start date		Mar. 15, 2022
Convertible notes, threshold percentage of stock price trigger		130.00%
Convertible notes, threshold trading days | d		20
Convertible notes, threshold consecutive trading days | d		30
Redemption price as percentage of the principal amount		100.00%
Redemption price as percentage of the principal amount subject to certain exceptions		100.00%

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	Mar. 01, 2018USD ($)ft²	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)
Commitment And Contingencies [Line Items]
Long-term lease agreement, area of office space | ft²	19,275
Lease term	11 years
Total lease payments	$ 7,300,000	$ 170,000	$ 167,000
Lessee, operating lease, existence of option to extend	true
Renewal term	5 years
Renewal term, description		The Company has the option to renew for two consecutive five-year periods from the end of the first term and the Company is not reasonably certain that the option to renew the Lease will be exercised. Under the Lease, the Company furnished a security deposit in the form of a standby letter of credit in the amount of $0.3 million, which was reduced by fifty-five thousand dollars on the first anniversary of the commencement date.  The security deposit will continue to be reduced by fifty-five thousand dollars every two years on the commencement date anniversary for eight years.
Security deposit in the form of a standby letter of credit	$ 300,000
Decrease in security deposit	$ 55,000
Maximum
Commitment And Contingencies [Line Items]
Milestone payments from the Company		$ 19,000,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Quantitative Information Associated with Amounts Recognized in Unaudited Condensed Consolidated Financial Statements for Lease (Detail) - USD ($) $ in Thousands	Mar. 01, 2018	Mar. 31, 2021	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Operating lease cost		$ 166	$ 166
Variable lease cost		(2)	21
Total operating lease expense		164	187
Total lease payments	$ 7,300	$ 170	$ 167
Remaining Lease term (years)		8 years 4 months 2 days	9 years 4 months 2 days
Discount rate		15.00%	15.00%

Commitments and Contingencies_3

Commitments and Contingencies - Future Minimum Lease Payments (Detail) $ in Thousands	Mar. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2021	$ 347
2022	527
2023	715
2024	730
2025	744
Thereafter	2,789
Total	$ 5,852

Commitments and Contingencies_4

Commitments and Contingencies - Presentation of Operating Lease Liability (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Present value of future minimum lease payments	$ 3,272
Operating lease liability, current portion	57	$ 52
Operating lease liability, long-term portion	3,215	$ 3,274
Total operating lease liability	3,272
Difference between future minimum lease payments and discounted cash flows	$ 2,580

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands	Jul. 16, 2020shares	Apr. 10, 2020USD ($)$ / sharesshares	Sep. 30, 2016$ / sharesshares	Mar. 31, 2021USD ($)$ / sharesshares	Mar. 31, 2020USD ($)	Dec. 31, 2020$ / sharesshares	Jul. 17, 2020shares
Schedule Of Capitalization Equity [Line Items]
Common stock, par value (in dollars per share) | $ / shares				$ 0.001		$ 0.001
Common stock, shares authorized (in shares) | shares	250,000,000			100,000,000		100,000,000	100,000,000
Common stock, shares issued (in shares) | shares				20,625,637		19,663,698
Common stock, shares outstanding (in shares) | shares				20,625,637		19,663,698
Common stock, reverse stock split				1-for-10
Common stock, reverse stock split ratio	0.1
Proceeds from common stock issued | $				$ 0	$ 214
Derivative liability fair value adjustment | $				(90)	700
Warrant liabilities fair value adjustment | $				1,296	4,768
Warrant liabilities | $				49,900	51,200
Warrants to purchase common stock associated with Loan Agreement
Schedule Of Capitalization Equity [Line Items]
Number of warrants issued to purchase common stock (in shares) | shares			12,243
Exercise price of warrants (in dollars per share) | $ / shares			$ 36.754
Warrant expiration period			5 years
Senior Convertible Note Purchase Agreement | Other (Income) Expense
Schedule Of Capitalization Equity [Line Items]
Derivative liability fair value adjustment | $				$ (100)	$ 700
Aspire Capital | Common Stock Purchase Agreement
Schedule Of Capitalization Equity [Line Items]
Number of purchase aggregate shares of common stock | shares		1,956,547
Percentage of common stock outstanding		19.99%
Number of shares committed | shares		70,910
Average purchase price of shares sold | $ / shares		$ 8.461
Percentage of common stock owned		19.99%
Aspire Capital | Common Stock Purchase Agreement | Maximum
Schedule Of Capitalization Equity [Line Items]
Sale of common stock at sole discretion | $		$ 20,000

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Common Stock Shares Activity (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance	$ 22,758	$ 12,895
Beginning balance (in shares)	19,663,698
Net loss	$ (4,676)	(7,002)
Stock-based compensation expense	398	410
Common stock issued, net of expenses	0	207
Common stock issued through employee stock purchase plan	6	18
Common stock issued for vested restricted stock units	(15)	(73)
Ending balance	$ 25,924	6,455
Ending balance (in shares)	20,625,637
April 2020 Notes
Common Stock Outstanding Roll Forward [Roll Forward]
Common stock issued for conversion of Notes	$ 7,453
Common Stock
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance	$ 20	$ 10
Beginning balance (in shares)	19,663,698	9,741,372
Net loss	$ 0	$ 0
Stock-based compensation expense	0	0
Common stock issued, net of expenses	$ 0	$ 0
Common stock issued, net of expenses (in shares)	0	28,527
Common stock issued through employee stock purchase plan	$ 0	$ 0
Common stock issued through employee stock purchase plan (in shares)	2,184	2,215
Common stock issued for vested restricted stock units	$ 0	$ 0
Common stock issued for vested restricted stock units (in shares)	675	15,490
Ending balance	$ 21	$ 10
Ending balance (in shares)	20,625,637	9,787,604
Common Stock | April 2020 Notes
Common Stock Outstanding Roll Forward [Roll Forward]
Common stock issued for conversion of Notes	$ 1
Common stock issued for conversion of Notes (in shares)	959,080
Additional Paid-in Capital
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance	$ 349,351	$ 284,313
Net loss	0	0
Stock-based compensation expense	398	410
Common stock issued, net of expenses	0	207
Common stock issued through employee stock purchase plan	6	18
Common stock issued for vested restricted stock units	(15)	(73)
Ending balance	357,192	284,875
Additional Paid-in Capital | April 2020 Notes
Common Stock Outstanding Roll Forward [Roll Forward]
Common stock issued for conversion of Notes	7,452
Accumulated Deficit
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance	(326,613)	(271,428)
Net loss	(4,676)	(7,002)
Stock-based compensation expense	0	0
Common stock issued, net of expenses	0	0
Common stock issued through employee stock purchase plan	0	0
Common stock issued for vested restricted stock units	0	0
Ending balance	(331,289)	$ (278,430)
Accumulated Deficit | April 2020 Notes
Common Stock Outstanding Roll Forward [Roll Forward]
Common stock issued for conversion of Notes	$ 0

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Reserved Shares of Common Stock for Future Issuance (Detail) - shares	Mar. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common shares reserved for future issuance	27,510,704	28,028,978
Stock options
Class of Stock [Line Items]
Common shares reserved for future issuance	1,371,606	830,343
Restricted Stock Units
Class of Stock [Line Items]
Common shares reserved for future issuance	96,974	29,087
Warrant | June 2016 Public Offering
Class of Stock [Line Items]
Common shares reserved for future issuance	421,867	421,867
Warrant | December 2019 Public Offering
Class of Stock [Line Items]
Common shares reserved for future issuance	4,472,205	4,472,205
Warrant | December 2020 Public Offering Series 1
Class of Stock [Line Items]
Common shares reserved for future issuance	6,800,000	6,800,000
Warrant | December 2020 Public Offering Series 2
Class of Stock [Line Items]
Common shares reserved for future issuance	6,800,000	6,800,000
Warrant | Prefunded Warrants to Purchase Common Stock Associated with December 2020 Public Offering
Class of Stock [Line Items]
Common shares reserved for future issuance	5,260,000	5,260,000
Warrant | Warrants to purchase common stock associated with Solar loan agreement
Class of Stock [Line Items]
Common shares reserved for future issuance	12,243	12,243
Series 1 Warrant | March 2018 Public Offering
Class of Stock [Line Items]
Common shares reserved for future issuance	798,810	798,810
March 2019 Notes
Class of Stock [Line Items]
Common shares reserved for future issuance	1,138,200	1,138,200
April 2020 Notes
Class of Stock [Line Items]
Common shares reserved for future issuance	0	1,299,790
2014 Equity Incentive Plan
Class of Stock [Line Items]
Common shares reserved for future issuance	318,097	146,488
2014 Employee Stock Purchase Plan
Class of Stock [Line Items]
Common shares reserved for future issuance	6,652	5,895
2015 Inducement Award Plan
Class of Stock [Line Items]
Common shares reserved for future issuance	14,050	14,050

Stock-based Compensation - 2014

Stock-based Compensation - 2014 Equity Incentive Plan (Details) - 2014 Equity Incentive Plan - shares	Jan. 01, 2021	Jan. 01, 2020	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of additional shares authorized	786,547	389,650
Possible future issuance under equity compensation plan (in shares)			318,097

Stock-based Compensation - 2015

Stock-based Compensation - 2015 Inducement Award Plan (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Apr. 30, 2021	Apr. 29, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (shares)	545,450
2015 Inducement Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Possible future issuance under equity compensation plan (in shares)	14,050
Granted (shares)	0	17,500
2015 Inducement Award Plan | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized under the plan (in shares)			500,000	90,000

Stock-based Compensation - Stoc

Stock-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Number of Shares
Beginning balance - Outstanding (shares)	830,343
Granted (shares)	545,450
Forfeited/Cancelled (shares)	(4,187)
Ending balance - Outstanding (shares)	1,371,606	830,343
Exercisable (shares)	500,625
Vested or expected to vest (shares)	1,371,606
Weighted- Average Exercise Price
Beginning balance - Outstanding (in dollars per share)	$ 21.52
Granted (in dollars per share)	7.57
Forfeited/Cancelled (in dollars per share)	8.48
Ending balance - Outstanding (in dollars per share)	16.01	$ 21.52
Exercisable (in dollars per share)	29.27
Vested or expected to vest (in dollars per share)	$ 16.01
Weighted- Average Remaining Contractual Life (in years)
Balance - Outstanding	8 years 3 months 29 days	7 years 8 months 15 days
Exercisable	6 years 8 months 19 days
Vested or expected to vest	8 years 3 months 29 days
Aggregate Intrinsic Value ($000)
Balance - Outstanding	$ 355	$ 96
Exercisable	37
Vested and expected to vest	$ 355

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Restricted Stock Units ("RSU") Activity (Details) - Outstanding restricted stock units	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Shares
Beginning balance - Outstanding (shares) | shares	29,087
Options granted in period (shares) | shares	73,675
Vested (shares) | shares	(5,788)
Ending balance - Outstanding (shares) | shares	96,974
Weighted Average Grant Date Fair Value Per Share
Beginning balance - Outstanding (in dollars per share) | $ / shares	$ 9.52
Granted (in dollars per share) | $ / shares	7.55
Vested (in dollars per share) | $ / shares	10.68
Ending balance - Outstanding (in dollars per share) | $ / shares	$ 7.95
Vesting percentage	25.00%
Vesting period of options	4 years

Stock-based Compensation - Comp

Stock-based Compensation - Compensation Cost (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based compensation expense	$ 398,000	$ 410,000
Tax benefit from compensation expense	$ 0	$ 0

Stock-based Compensation - Expe

Stock-based Compensation - Expense Related to Stock Options (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to stock options	$ 398	$ 410
Research and development, net
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to stock options	126	136
Selling, general and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to stock options	$ 272	$ 274

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Instruments Measured on a Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	$ 92,284	$ 93,314
Fair value of financial liabilities	52,478	57,110
Warrant liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	49,860	51,156
Derivative liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	2,618	5,954
Cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	236	117
Restricted cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	273	273
Money market funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	91,775	92,924
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	92,284	93,314
Fair value of financial liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Warrant liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Derivative liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	236	117
Quoted Prices in Active Markets for Identical Assets (Level 1) | Restricted cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	273	273
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	91,775	92,924
Significant Other Observable Inputs (Level 2)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Fair value of financial liabilities	0	0
Significant Other Observable Inputs (Level 2) | Warrant liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	0	0
Significant Other Observable Inputs (Level 2) | Derivative liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	0	0
Significant Other Observable Inputs (Level 2) | Cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Significant Other Observable Inputs (Level 2) | Restricted cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Significant Other Observable Inputs (Level 2) | Money market funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Significant Unobservable Inputs (Level 3)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Fair value of financial liabilities	52,478	57,110
Significant Unobservable Inputs (Level 3) | Warrant liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	49,860	51,156
Significant Unobservable Inputs (Level 3) | Derivative liabilities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial liabilities	2,618	5,954
Significant Unobservable Inputs (Level 3) | Cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Significant Unobservable Inputs (Level 3) | Restricted cash
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	0	0
Significant Unobservable Inputs (Level 3) | Money market funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of financial assets	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - Significant Unobservable Inputs (Level 3)	Mar. 31, 2021	Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, maturity date	Jun. 12, 2023
Stock Price Volatility
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative liabilities, unobservable inputs rate	61.5
Stock Price Volatility | Minimum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, stock price volatility rate	69.6
Stock Price Volatility | Maximum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, stock price volatility rate	82.5
Stock Price Volatility | Weighted Average
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, stock price volatility rate	77.6
Weighted Average Expected Term
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, expected term	10 months 24 days
Weighted Average Expected Term | Minimum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, expected term		7 months 28 days
Weighted Average Expected Term | Maximum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liabilities, expected term		2 years 2 months 12 days
Market Credit Spread
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative liabilities, unobservable inputs rate	1,451
Estimated Yield
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative liabilities, unobservable inputs rate	15.1
Discounts for Lack of Marketability | March 2019 Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior convertible notes, unobservable inputs rate	7.1

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Reconciliation of Beginning and Ending Balances for Liabilities Measured at Fair Value on Recurring Basis (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Warrant liabilities
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 51,156
Gain (loss) adjustment to fair value	(1,296)
Ending balance	49,860
Derivative liabilities
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	5,954
Adjustment for conversion of April 2020 Notes	(3,426)
Gain (loss) adjustment to fair value	90
Ending balance	$ 2,618

License Agreement Revenue - Add

License Agreement Revenue - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Feb. 28, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Income tax expense	$ 1,100,000	$ 0
Exclusive License And Collaboration Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Non refundable upfront payment received	10,000,000
Transaction price	12,100,000
Fixed upfront cash payment	10,000,000
Amount related to withholding tax obligations	1,100,000
Revenue recognized	1,100,000
Income tax expense	1,100,000
Exclusive License And Collaboration Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential development and commercial milestones yet to receive			$ 110,000,000
Asset Purchase Agreement | Cypralis Limited
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized	0
License Agreement | Waterstone Pharmaceutical HK Limited
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized	$ 0

Subsequent Events - Additional

Subsequent Events - Additional Information (Details)	1 Months Ended
	May 31, 2021USD ($)Tranche$ / shares	Mar. 31, 2021$ / shares	Dec. 31, 2020$ / shares
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Subsequent Event | SVB
Subsequent Event [Line Items]
Minimum outstanding term loan principal percentage for financial covenant waived	50.00%
Subsequent Event | Loan and Security Agreement | Hercules Capital Inc. and Silicon Valley Bank
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) | $ / shares	$ 0.001
Multiplier value by aggregate amount of the term loan advances divided by exercise price of warrants to calculate number of shares for purchase	0.04
Subsequent Event | Loan and Security Agreement | Term Loan
Subsequent Event [Line Items]
Notes maturity date	Mar. 3, 2025
Basis spread on variable rate (as a percent)	9.05%
Debt instrument maturity date subject to occurrence of certain conditions	May 1, 2025
Subsequent Event | Loan and Security Agreement | Term Loan | Prime Rate
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	5.80%
Subsequent Event | Loan and Security Agreement | Term Loan | Hercules Capital Inc. and Silicon Valley Bank
Subsequent Event [Line Items]
Face amount	$ 60,000,000
Number of available tranches | Tranche	4
Subsequent Event | Loan and Security Agreement | Initial Tranche of Term Loan
Subsequent Event [Line Items]
Additional borrowing amount available	$ 20,000,000
Subsequent Event | Loan and Security Agreement | Second Tranche of Term Loan
Subsequent Event [Line Items]
Additional borrowing amount available	10,000,000
Subsequent Event | Loan and Security Agreement | Third Tranche of Term Loan
Subsequent Event [Line Items]
Additional borrowing amount available	5,000,000
Subsequent Event | Loan and Security Agreement | Fourth Tranche of Term Loan
Subsequent Event [Line Items]
Additional borrowing amount available	25,000,000
Increment debt amount	5,000,000
Subsequent Event | New Jersey
Subsequent Event [Line Items]
Selling value of unused net operating losses and research and development credit	$ 4,200,000