ContraFect (CFRXQ) 10-K 24 Mar 22 2021 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 17, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Entity Interactive Data Current	Yes
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Trading Symbol	CFRX
Entity Registrant Name	ContraFect Corporation
Entity Central Index Key	0001478069
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	false
Entity Public Float			$ 173.1
Title of 12(b) Security	Common Stock, Par Value $0.0001 per share
Security Exchange Name	NASDAQ
Entity Shell Company	false
Entity Address, State or Province	NY
Entity Common Stock, Shares Outstanding		39,332,721
ICFR Auditor Attestation Flag	false
Auditor Name	Ernst & Young, LLP
Auditor Firm ID	42
Auditor Location	Hartford, Connecticut
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-36577
Entity Tax Identification Number	39-2072586
Entity Address, Address Line One	28 Wells Avenue
Entity Address, Address Line Two	3rd Floor
Entity Address, City or Town	Yonkers
Entity Address, Postal Zip Code	10701
City Area Code	914
Local Phone Number	207-2300

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 16,654	$ 15,485
Marketable securities	37,631	27,005
Prepaid expenses	4,439	3,084
Other current assets	4,140	1,081
Total current assets	62,864	46,655
Property and equipment, net	741	910
Operating lease right-of-use assets	2,544	2,811
Other assets	613	740
Total assets	66,762	51,116
Current liabilities:
Accounts payable	2,389	1,806
Accrued liabilities	9,128	3,610
Current portion of lease liabilities	657	644
Total current liabilities	12,174	6,060
Warrant liabilities	2,530	29,404
Long-term portion of lease liabilities	2,609	2,959
Other liabilities	73	73
Total liabilities	17,386	38,496
Commitments and contingencies (Note 8)
Stockholders' equity:
Preferred stock, $0.0001 par value, 25,000,000 shares authorized and none issued or outstanding at December 31, 2021 and 2020
Common stock, $0.0001 par value, 125,000,000 shares authorized; 39,332,721 and 27,810,161 shares issued and outstanding at December 31, 2021 and 2020	4	3
Additional paid-in capital	310,008	252,908
Accumulated other comprehensive loss	(84)	(21)
Accumulated deficit	(260,552)	(240,270)
Total stockholders' equity	49,376	12,620
Total liabilities and stockholders' equity	$ 66,762	$ 51,116

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred stock, shares outstanding	0	0
Preferred Stock, Shares Issued	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	39,332,721	27,810,161
Common stock, shares outstanding	39,332,721	27,810,161

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating expenses:
Research and development, including stock-based compensation of $933, $655 and $469, respectively	$ 35,508	$ 22,614	$ 18,057
General and administrative, including stock-based compensation of $2,261, $1,921 and $977, respectively	11,757	11,625	9,809
Total operating expenses	47,265	34,239	27,866
Loss from operations	(47,265)	(34,239)	(27,866)
Other income (expense):
Interest income	109	192	359
Other expense	0	(2,165)
Change in fair value of warrant liabilities	26,874	8,056	14,713
Total other income	26,983	6,083	15,072
Net loss	$ (20,282)	$ (28,156)	$ (12,794)
Per share information:
Net loss per share of common stock, basic and diluted	$ (0.55)	$ (1.24)	$ (1.54)
Basic and diluted weighted average shares outstanding	36,775,950	22,763,528	8,283,509

Consolidated Statements of Op_2

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock-based compensation expense	$ 3,194	$ 2,576	$ 1,447
Research and Development Expense [Member]
Stock-based compensation expense	933	655	469
General and Administrative Expense [Member]
Stock-based compensation expense	$ 2,261	$ 1,921	$ 977

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (20,282)	$ (28,156)	$ (12,794)
Other comprehensive gain (loss):
Unrealized gain (loss) on available-for-sale securities	(63)	(21)	30
Comprehensive loss	$ (20,345)	$ (28,177)	$ (12,764)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2018	$ 5,542	$ 1	$ 204,891	$ (30)	$ (199,320)
Beginning Balance, Shares at Dec. 31, 2018		7,940,931
Issuance of securities in registered offering	20,034	$ 1	20,033
Issuance of securities in registered offering, Shares		6,280,000
Issuance of securities in private placement	3,000		3,000
Issuance of securities in private placement, Shares		1,111,111
Financing cost of sale of securities	(1,713)		(1,713)
Stock-based compensation	1,447		1,447
Unrealized loss on marketable securities	30			30
Net loss	(12,794)				(12,794)
Ending balance at Dec. 31, 2019	15,546	$ 2	227,658		(212,114)
Ending balance, Shares at Dec. 31, 2019		15,332,042
Issuance of securities in registered offering	21,108	$ 1	21,107
Issuance of securities in registered offering, Shares		11,797,752
Issuance of securities in private placement	3,000		3,000
Issuance of securities in private placement, Shares		674,156
Financing cost of sale of securities	(1,462)		(1,462)
Issuance of common stock for exercise of warrants	$ 29		29
Issuance of common stock for exercise of warrants, Shares	5,850	5,850
Stock-based compensation	$ 2,576		2,576
Unrealized loss on marketable securities	(21)			(21)
Issuance of common stock for exercise of options, Shares		361
Net loss	(28,156)				(28,156)
Ending balance at Dec. 31, 2020	12,620	$ 3	252,908	(21)	(240,270)
Ending balance, Shares at Dec. 31, 2020		27,810,161
Issuance of securities in registered offering	57,500	$ 1	57,499
Issuance of securities in registered offering, Shares		11,500,000
Financing cost of sale of securities	(3,703)		(3,703)
Issuance of common stock for exercise of warrants	$ 110		110
Issuance of common stock for exercise of warrants, Shares	22,560	22,560
Stock-based compensation	$ 3,194		3,194
Unrealized loss on marketable securities	$ (63)			(63)
Issuance of common stock for exercise of options, Shares	0
Net loss	$ (20,282)				(20,282)
Ending balance at Dec. 31, 2021	$ 49,376	$ 4	$ 310,008	$ (84)	$ (260,552)
Ending balance, Shares at Dec. 31, 2021		39,332,721

Statements of Cash Flows

Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (20,282)	$ (28,156)	$ (12,794)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	148	168	169
Stock-based compensation expense	3,194	2,576	1,447
Issuance costs allocated to warrants		2,175
Change in fair value of warrant liabilities	(26,874)	(8,056)	(14,713)
Net amortization of premium paid on marketable securities	924	378	171
Changes in operating assets and liabilities:
(Increase) decrease in prepaid expenses and other current and non-current assets	(4,336)	1,738	(1,263)
Increase (decrease) in accounts payable, accrued liabilities and other liabilities	6,101	(4,010)	(445)
Net cash used in operating activities	(41,125)	(33,187)	(27,428)
Cash flows from investing activities
Purchases of marketable securities	(48,698)	(47,555)
Proceeds from maturities of marketable securities	37,085	20,151	21,991
Purchases of property and equipment			(20)
Net cash (used in) provided by investing activities	(11,613)	(27,404)	21,971
Cash flows from financing activities
Proceeds from issuance of equity securities	57,500	55,500	23,034
Payment of financing costs of securities sold	(3,703)	(3,637)	(1,713)
Proceeds from exercise of warrants	110	29
Net cash provided by financing activities	53,907	51,892	21,321
Net (decrease) increase in cash and cash equivalents	1,169	(8,699)	15,864
Cash and cash equivalents at beginning of period	15,485	24,184	8,320
Cash and cash equivalents at end of period	$ 16,654	15,485	24,184
Supplemental disclosures of cash flow information:
Prepaid expenses in accrued liabilities			4,097
Right-of-use assets obtained in exchange for lease obligations			4,149
Leasehold improvement obtained in exchange for lease incentive obligations			$ 189
Issuance of warrants to purchase common stock		$ 31,391

Organization and Description of

Organization and Description of Business	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Organization and Description of Business	1. Organization and Description of Business Organization and Business ContraFect Corporation (the “Company”) is a clinical-stage biotechnology company focused on the discovery and development of direct lytic agents (“DLAs”), including lysins and amurin peptides, as new medical modalities for the treatment of life-threatening, antibiotic-resistant infections. The Company intends to address antibiotic-resistant infections using product candidates from our lysin and amurin peptide platforms. DLAs are fundamentally different than antibiotics and offer a potential paradigm shift in the treatment of antibiotic-resistant infections. The Company’s most advanced product candidate is exebacase, a lysin which targets S. aureus S. aureus S. aureus The Company has incurred recurring losses since inception as a research and development organization and has an accumulated deficit of $260.6 million as of December 31, 2021. For the year ended December 31, 2021, the Company used $41.1 million of cash in operations. The Company has relied on its ability to fund its operations through public and private debt and equity financings, and, to a lesser extent, grant funding. The Company expects operating losses and negative cash flows to continue at significant levels in the future as it continues its clinical trials. As of December 31, 2021, the Company had approximately $54.3 million in cash, cash equivalents and marketable securities, which, without additional funding, the Company believes will not be sufficient to meet its obligations within the next twelve months from the date of issuance of these consolidated financial statements. The Company plans to continue to fund its operations through public or private debt and equity financings, but there can be no assurances that such financing will continue to be available to the Company on satisfactory terms, or at all. As such, under the requirements of Accounting Standard Codification (“ASC”) 205-40, The consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates continuity of operations, the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. On August 14, 2020, the Company filed a shelf registration statement on Form S-3 S-3”) S-3 S-3 time-to-time On March 22, 2021, the Company completed an underwritten public offering under the Form S-3 On March 10, 2021, the Company entered into a cost-share contract (the “BARDA Contract”) with BARDA, a division of the U.S. Department of Health and Human Services’ Office of the Assistant Secretary for Preparedness and Response. Under the BARDA Contract, the Company will receive funding of up to an estimated $86.8 million to advance the development of exebacase. The base period for the BARDA Contract includes government funding of up to $9.8 million to reimburse expenses for to support the conduct of the ongoing Phase 3 clinical trial and futility analysis. Following successful completion of the base period, the BARDA Contract provides for approximately $77.0 million of additional BARDA funding for five option stages in support of the completion of the Phase 3 clinical trial of exebacase, further clinical and non-clinical period-of-performance On May 27, 2020, the Company completed an underwritten public offering of 11,797,752 shares of its common stock and warrants to purchase an additional 8,848,314 shares of its common stock at an exercise price of $4.90 per share (the “2020 Offering”). The public offering price was $4.45 for one share of common stock and an accompanying warrant to purchase 0.75 shares of common stock, resulting in net proceeds to the Company of approximately $48.9 million after underwriting discounts and commissions and offering expenses payable by the Company. The Company completed a concurrent private placement to Pfizer Inc. (“Pfizer”) of 674,156 shares of common stock and an accompanying warrant to purchase an additional 505,617 shares of its common stock at an exercise price of $4.90 per share (the “Pfizer Warrant”). The offering price for one share of common stock and an accompanying warrant to purchase 0.75 shares of common stock was at a price of $4.45 per share of common stock, resulting in net proceeds to the Company of approximately $3.0 million. On December 18, 2019, the Company completed an underwritten public offering of 2,565,000 shares of its common stock at a public offering price of $3.90 per share, resulting in gross proceeds to the Company of approximately $10.0 million. On December 12, 2019, the Company completed an underwritten public offering of 3,715,000 shares of its common stock at a public offering price of $2.70 per share and a concurrent private placement of 1,111,111 shares of common stock to Pfizer Inc. at a price of $2.70 per share, resulting in gross proceeds to the Company of approximately $13.0 million. The combined net proceeds of both public offerings together with the private placement was $21.3 million after underwriting discounts and commissions and offering expenses payable by the Company. The significant increases in common stock outstanding are expected to impact the year-over-year comparability of the Company’s net loss per share calculations.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of significant accounting policies Basis of Presentation The accompanying financial information has been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). Principles of Consolidation The Company has a wholly-owned subsidiary, ContraFect International Limited, in Scotland that establishes legal status for interactions with the European Economic Area. This subsidiary is dormant or is otherwise non-operative. Segment and Geographic Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision-making group, in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the chief executive officer. The Company and the chief decision maker view the Company’s operations and manage its business as one operating segment. The Company operates in only one geographic segment. Significant Risks and Uncertainties The Company’s operations are subject to a number of factors that can affect its operating results and financial condition. Such factors include, but are not limited to: the results of clinical testing and trial activities of the Company’s products, the Company’s ability to obtain regulatory approval to market its products, and, if approved, the price of, and demand for, the Company’s products, competition from products manufactured and sold or being developed by other companies, the Company’s ability to negotiate favorable manufacturing and other agreements for its products and the Company’s ability to raise capital. The Company currently relies on a single manufacturer of exebacase drug substance and drug product, located in the United Kingdom, and there is no long-term supply agreement in place. A sustained disruption in the operations of this manufacturer or in the event the Company would need to change to a new supplier, could result in a significant delay in the ability of the Company to complete the activities needed to support a Biologics License Application for, and, if approved, commercialization of exebacase. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The Company bases estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to research and development prepaid expenses and accruals, stock-based compensation, warrant valuation and realization of net deferred income tax assets. The Company’s actual results may differ from these estimates under different assumptions or conditions. There have been no significant changes from the Company’s original estimates in any periods presented. Concentrations of Credit Risk Financial instruments which potentially subject the Company to credit risk consist primarily of cash, cash equivalents and marketable securities. The Company holds these investments in highly rated financial institutions, and, by policy, limits the amounts of credit exposure to any one financial institution. These amounts at times may exceed federally insured limits. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds. The Company has no off-balance Cash and Cash Equivalents The Company considers all highly liquid investments with maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents include bank demand deposits, marketable securities with maturities of three months or less at purchase, and money market funds that invest primarily in certificates of deposit, commercial paper and U.S. government and U.S. government agency obligations. Cash equivalents are reported at fair value. Marketable Securities Marketable securities consists of investments in corporate debt securities. Management determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its marketable securities as available-for-sale Investments – Debt and Equity Securities classified as long-term assets on the consolidated balance sheets if (i) the Company has the intent and ability to hold the investments for a period of at least one year and (ii) the contractual maturity date of the investments is greater than one year. Marketable securities are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive loss in stockholders’ equity and a component of total comprehensive loss in the consolidated statements of comprehensive loss, until realized. The fair value of these securities is based on quoted prices for identical or similar assets. Realized gains and losses are included in interest income in the consolidated statement of operations on a specific-identification basis. The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period. Fair Value of Financial Instruments The Company’s financial instruments consist of cash and cash equivalents, marketable securities, accounts payable, accrued liabilities and warrant liabilities. Fair value estimates of these instruments are made at a specific point in time, based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and therefore cannot be determined with precision. The fair value of the Company’s warrant liabilities is The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC Topic 820, Fair Value Measurements and Disclosures Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly. Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The Company had no liabilities classified as Level 1 or Level 2. The carrying amounts reported in the accompanying financial statements for accounts payable and accrued expenses approximate their respective fair values due to their short-term maturities. The fair value of the warrant liabilities is Property, Office Equipment, and Leasehold Improvements Property and equipment are recorded at cost less accumulated depreciation. Depreciation of property and equipment is provided by the straight-line method over their estimated useful lives, ranging from three Leasehold improvements are amortized on a straight-line basis over the useful life of the Impairment of Long-lived Assets In accordance with ASC 360, Property, Plant, and Equipment Research and Development Costs Research and development costs are charged to expense as incurred and are typically made up of salaries and benefits, clinical trial activities, drug development and manufacturing costs, and third-party service fees, including for clinical research organizations and investigative sites. Costs for certain development activities, such as clinical trials, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, or information provided by vendors on their actual costs incurred. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected in the financial statements as prepaid expenses or accrued liabilities. Stock-based Compensation The Company accounts for stock-based compensation in accordance with ASC 718, Compensation—Stock Compensation, non-employees, The fair value of options is calculated using the Black-Scholes option pricing model on the date of grant based on key assumptions such as stock price, risk free interest rates, expected volatility, expected term, and expected dividend yield. The Company’s estimates of these assumptions are based on historical data and judgment regarding future trends and factors. Income Taxes The Company uses the asset and liability method to calculate deferred tax assets and liabilities. Deferred taxes are recognized based on the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases using enacted tax rates expected to apply to taxable income in the years in which those differences are expected to be recovered or settled. The Company records a valuation allowance against a deferred tax asset when it is more-likely-than-not The Company is subject to federal, state and local taxes and follows a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The Company recognizes tax benefits or expenses of uncertain tax positions in the year such determination is made when the position is “more likely than not” to be sustained assuming examination by tax authorities. Management has reviewed the Company’s tax positions for all open tax years (tax years ended December 31, 2010 through December 31, 2021) and concluded that no provision for unrecognized tax benefits or expense is required in these financial statements. There are no income tax audits in progress as of December 31, 2021. Government Contracts and Grant Agreements The Company recognizes a receivable, which is included in other current assets on its consolidated balance sheet, and the related reduction in its research and development expenses when the actual reimbursable costs have been incurred and there is reasonable assurance that the Company has complied with the conditions of the applicable government contract or grant agreement and the amounts will be received. The Company recognized a reduction to its research and development expense in the amount of approximately $10.5 million, $4.2 million and $3.6 million for the years ended December 31, 2021, 2020 and 2019 respectively. The receivable for government contracts and grant agreements as of December 31, 2021 and 2020 was approximately $4.1 million and $ 1.1 million, respectively, and is included in other current assets on the consolidated balance sheet. The Company has approximately $7.7 million of committed government contract and grant agreement funding remaining as of December 31, 2021. Net Loss per Share Applicable to Common Stockholders Basic net loss per share applicable to common stockholders is calculated by dividing net loss applicable to common stockholders by the weighted average shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share applicable to common stockholders is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the dilutive net loss per share applicable to common stockholders’ calculation, stock options and warrants are considered to be common stock equivalents but are excluded from the calculation of diluted net loss per share applicable to common stockholders, as their effect would be anti-dilutive; therefore, basic and diluted net loss per share applicable to common stockholders were the same for all periods presented. Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions, and other events and circumstances from non-owner available-for-sale Recently Adopted Accounting Pronouncements Fair Value Measurements On January 1, 2020, the Company adopted Accounting Standards Update No. 2018-13- Fair Value Measurement (Topic 820). Income Taxes On January 1, 2021, the Company adopted Accounting Standards Update No. 2019-12, Income Taxes (Topic 740) Recently Issued Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued a new Accounting Standards Update, Financial Instruments-Credit Losses (ASU 2016-13). 2016-13 available-for-sale In November 2021, the FASB issued a new Accounting Standards Update, Disclosure by Business Entities about Government Assistance (ASU 2021-10)

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	3. Marketable Securities Marketable securities at December 31, 2021 consisted of the following (in thousands): Marketable Securities Amortized Cost Unrealized Gains Unrealized Losses Fair Current: Corporate debt $ 37,715 $ — $ (84 ) $ 37,631 Marketable securities at December 31, 2020 consisted of the following (in thousands): Marketable Securities Amortized Cost Unrealized Gains Unrealized Losses Fair Current: Corporate debt $ 27,026 $ 6 $ (27 ) $ 27,005 Corporate debt includes obligations issued by investment-grade corporations. At December 31, 2021, the Company held only investments that have maturities of less than one year. At December 31, 2021 and December 31, 2020, the Company held 23 and 15 debt securities, respectively, that individually and in total were in an immaterial unrealized loss position for . The aggregate fair value of debt securities in an unrealized loss position at December 31, 2021 and December 31, 2020 was $37,631 and $18,116, respectively. The Company evaluated its securities for other-than-temporary impairment and considered the decline in market value for the securities to be primarily attributable to current economic and market conditions. It was not more likely than not that the Company would have been required to sell the securities prior to the recovery of the amortized cost basis. Based on this analysis, these marketable securities were not considered to be other-than-temporarily impaired as of December 31, 2021 and December 3 1

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2021 and December 31, 2020 (in thousands): Fair Value Measurement as of December 31, 2021 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Cash equivalents $ 7,734 $ — $ — Marketable securities 37,631 — — Warrant liabilities — — 2,530 Total $ 45,365 $ — $ 2,530 Fair Value Measurement as of December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Cash equivalents $ 12,921 $ — $ — Marketable securities 27,005 — — Warrant liabilities — — 29,404 Total $ 39,926 $ — $ 29,404 The Company issued warrants to the purchasers of its 2016 Offering (the “2016 Warrants”). The Company determined that these warrants should be classified as a liability and considered as a Level 3 financial instrument (see also Note 9, “Capital Structure”). The 2016 Warrants were re-measured As of December 31, 2020 Expected volatility 59.7 % Remaining contractual term (in years) 0.58 Risk-free interest rate 0.09 % Expected dividend yield — % The Company issued warrants to the purchasers of its 2017 Offering (the “2017 Warrants”). The Company determined that these warrants should be classified as a liability and considered as a Level 3 financial instrument (see also Note 9, “Capital Structure”). The 2017 Warrants are re-measured The following assumptions were used in a Black-Scholes option-pricing model to determine the fair value of the warrant liability: As of December 31, 2021 As of December 31, 2020 Expected volatility 56.5 % 100.1 % Remaining contractual term (in years) 0.58 1.58 Risk-free interest rate 0.19 % 0.12 % Expected dividend yield — % — % The Company issued warrants to the purchasers of its 2020 Offering (the “2020 Warrants”). The Company determined that these warrants should be classified as a liability and considered as a Level 3 financial instrument (see also Note 9, “Capital Structure”). The 2020 Warrants are re-measured The following assumptions were used in a Black-Scholes option-pricing model to determine the fair value of the warrant liability: As of December 31, 2021 As of December 31, 2020 Expected volatility 61.9 % 111.9 % Remaining contractual term (in years) 1.42 2.42 Risk-free interest rate 0.56 % 0.15 % Expected dividend yield — % — % The following tables present a reconciliation of the Company’s financial liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2021, 2020 and 2019 (in thousands): Warrant liabilities Year Ended December 31, 2021 2020 2019 Balance at beginning of period $ 29,404 $ 6,069 $ 20,782 Issuance of 2020 Warrants — 31,391 — Change in fair value (26,874 ) (8,056 ) (14,713 ) Balance at end of period $ 2,530 $ 29,404 $ 6,069 The key inputs into the Black-Scholes option pricing model are the per share value and the expected volatility of the Company’s common stock. Significant changes in these inputs will directly increase or decrease the estimated fair value of the Company’s warrant liability.

Property, Equipment, and Leaseh

Property, Equipment, and Leasehold Improvements	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Property, Equipment, and Leasehold Improvements	5. Property, Equipment, and Leasehold Improvements Property, equipment, and leasehold improvements, at cost, consisted of the following for the years ended December 31, 2021 and 2020 (in thousands): December 31, 2021 2020 Computer equipment $ 20 $ 20 Furniture 435 435 Lab equipment 1,864 1,864 Leasehold improvements 1,985 2,006 4,304 4,325 Less: accumulated depreciation and amortization (3,563 ) (3,415 ) $ 741 $ 910 Depreciation expense was $148, $168 and $169 for the years ended December 31, 2021, 2020 and 2019, respectively.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2021
Payables and Accruals [Abstract]
Accrued Liabilities	6. Accrued Liabilities Accrued liabilities consisted of the following for the years ended December 31, 2021 and 2020 (in thousands): December 31, 2021 2020 Accrued research and clinical development service fees $ 5,641 $ 801 Accrued compensation costs 2,215 2,069 Accrued professional fees 819 457 Accrued facilities operation expenses 307 173 Other accrued expenses 146 110 $ 9,128 $ 3,610

Net Loss Per Share of Common St

Net Loss Per Share of Common Stock	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share of Common Stock	7. Net Loss Per Share of Common Stock Diluted loss per share is the same as basic loss per share for all periods presented because the effects of potentially dilutive items were anti-dilutive given the Company’s net loss. Basic loss per share is computed by dividing net loss available to common stockholders by the weighted-average number of common shares outstanding. The following table sets forth the computation of basic and diluted loss per share for common stockholders (in thousands, except share and per share data): Year Ended December 31, 2021 2020 2019 Net loss applicable to common stockholders $ (20,282 ) $ (28,156 ) $ (12,794 ) Weighted average shares of common stock outstanding 36,775,950 22,763,528 8,283,509 Net loss per share of common stock—basic and diluted $ (0.55 ) $ (1.24 ) $ (1.54 ) The following potentially dilutive securities outstanding at December 31, 2021, 2020 and 2019 have been excluded from the computation of diluted weighted average shares outstanding, as they would have been antidilutive given the Company’s net loss: December 31, 2021 2020 2019 Options to purchase common stock 2,899,694 1,853,841 1,216,338 Warrants to purchase common stock 10,926,594 12,350,293 3,033,910 13,826,288 14,204,134 4,250,248

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Operating Leases In December 2010, the Company entered into a non-cancellable In January 2012, the Company entered into a non-cancellable The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): December 31, Description 2021 2020 Operating lease liabilities: Current portion of lease liabilities $ 657 $ 644 Long-term portion of lease liabilities $ 2,609 $ 2,959 Operating lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. The leases are renewable at the end of the lease term at the Company’s option. For the purposes of determining the remaining lease term in contemplation of available extensions, the Company did not consider either renewal to be probable at this time. In determining the present value of lease payments, the Company estimated its incremental borrowing rate based on the information available at the adoption date of Topic 842. As of January 1, 2019, the remaining lease term was 9.0 years and the discount rate used to determine the operating lease liability was 9.93%. As of December 31, 2021, the maturities of the Company’s operating lease liabilities were as follows (in thousands): Amount Year ending December 31: 2022 $ 693 2023 707 2024 721 2025 736 2026 750 Thereafter 702 Total lease payments 4,309 Less: Present value adjustment (1,043 ) Operating lease liabilities $ 3,266 Lease costs under the terms of the Company’s leases for the years ended December 31, 2021 and 2020 are as follows (in thousands): Year Ended December 31, 2021 2020 Operating lease cost (1) $ 616 $ 615 Variable lease costs (2) 148 126 Total lease cost $ 764 $ 741 (1) Operating lease payments included in the measurement of the Company’s lease liabilities are comprised of fixed payments according to the terms of the Company’s leases. (2) Variable lease payments consist of the Company’s utility costs billed by and paid to its landlord. Variable lease payments are presented as operating expenses in the Company’s Consolidated Statement of Operations in the same line item as expense arising from fixed lease payments and in net cash used in operating activities in the Company’s Statement of Cash Flows. Rockefeller University License Agreements The Company has entered into the following license agreements with The Rockefeller University: • On July 12, 2011, the Company entered into a license agreement for the worldwide, exclusive right to a patent covering the composition of matter for the lysin PlySS2 for the treatment and prevention of diseases caused by gram-positive bacteria (the “CF-301 CF-301 • On June 1, 2011, the Company entered into a license agreement for the exclusive rights to The Rockefeller University’s interest in a joint patent application covering the method of delivering antibodies through the cell wall of gram-positive bacteria to the periplasmic space. This intellectual property was developed as a result of the sponsored research agreement between the Company and The Rockefeller University and was jointly discovered and filed by the two parties. • On September 23, 2010, the Company entered into a license agreement for the worldwide, exclusive right to develop, make, have made, use, import, lease, sell, and offer for sale products that would otherwise infringe a claim of the suite of patents and patent applications covering the composition of matter for eight individual lysin molecules for the treatment and prevention of diseases caused by gram-positive bacteria. The lysins in this suite have activity against Group B Streptococci Staphylococcus aureus, Streptococcus pneumonia, Bacillus anthracis, Enterococcus faecalis and Enterococcus faecium In consideration for the licenses, the Company paid Rockefeller license initiation fees in cash and stock. The Company paid annual maintenance fees of $200,000 in each of 2021, 2020 and 2019, and are required to pay $200,000 each year thereafter until the licenses terminate. Depending on the success of its programs, the Company may also incur regulatory milestone payments up to a total of $5.0 million and royalties of up to % on net sales from products to Rockefeller. We are allowed to grant sublicenses to third parties without prior approval, subject to certain conditions and the payment of a certain percentage of all payments we receive from sublicensees. There CF-301 CF-301 Each license agreement terminates upon the later of (i) the expiration or abandonment of the last licensed patent under the license agreement to expire or become abandoned, or (ii) 10 years after the first commercial sale of the first licensed product. The Rockefeller University may terminate any license agreement in the event of a breach of such agreement by the Company or if the Company challenges the validity or enforceability of the underlying patent rights. The Company may terminate any license agreement at any time on 60 days’ notice. Legal Contingencies From time to time, the Company may be involved in disputes and legal proceedings in the ordinary course of its business. These proceedings may include allegations of infringement of intellectual property, employment or other matters. The Company records a liability in its financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in a liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss to the extent necessary to make the financial statements not misleading. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in the Company’s financial statements. The Company currently has no legal proceedings ongoing that management estimates could have a material effect on the Company’s financial statements.

Capital Structure

Capital Structure	12 Months Ended
	Dec. 31, 2021
Federal Home Loan Banks [Abstract]
Capital Structure	9 Common Stock As of December 31, 2021, the Company was authorized to issue 125,000,000 shares of common stock at $0.0001 par value per share. Follow-on On March 22, 2021, the Company completed an underwritten public offering of 11,500,000 shares of its common stock, including shares sold pursuant to the fully exercised overallotment option granted to the underwriters in connection with the offering, at a public offering price of $5.00 per share, resulting in net proceeds to the Company of approximately $53.8 million after underwriting discounts and commissions and offering expenses payable by the Company. On May 27, 2020, the Company completed an underwritten public offering of 11,797,752 shares of its common stock and warrants to purchase an additional 8,848,314 shares of its common stock at an exercise price of $4.90 per share. The public offering price was $4.45 for one share of common stock and an accompanying warrant to purchase 0.75 shares of common stock, resulting in net proceeds to the Company of approximately $48.9 million after underwriting discounts and commissions and offering expenses payable by the Company. The Company completed a concurrent private placement to Pfizer of 674,156 shares of common stock and an accompanying warrant to purchase an additional 505,617 shares of its common stock at an exercise price of $4.90 per share at a price of $4.45 for one share of common stock and an accompanying warrant to purchase 0.75 shares of common stock, resulting in net proceeds to the Company of approximately $3.0 million. Warrants to purchase 22,560 and 5,850 shares of common stock were exercised during the years ended December 31, 2021 and 2020, respectively. On December 18, 2019, the Company completed an underwritten public offering of 2,565,000 shares of its common stock resulting in gross proceeds to the Company of approximately $10.0 million. On December 12, 2019, the Company completed an underwritten public offering of 3,715,000 shares of its common stock and a concurrent private placement of 1,111,111 shares of common stock to Pfizer Inc. resulting in total gross proceeds to the Company of approximately $13.0 million. The combined net proceeds of both public offerings together with the private placement was $21.3 million after underwriting discounts and commissions and offering expenses payable by the Company. The Company issued warrants in its 2020, 2017 and 2016 offerings of securities. These warrants contain a fundamental transaction provision that obligates the Company to cash settle the warrants under a limited set of conditions not entirely within the Company’s control. Due to this conditional obligation, the Company determined that the 2020 Warrants, the 2017 Warrants and the 2016 Warrants should be classified as liabilities in the Company’s consolidated balance sheet. At issuance, the Company determined the fair value of the 2020 Warrants, the 2017 Warrants and 2016 Warrants to be $31.4 million, $12.4 million and $18.6 million, respectively, and reclassified these balances from stockholders’ equity to warrant liability. The fair value of these warrants is re-measured The Pfizer Warrant does not contain the same fundamental transaction provision that obligates the Company to cash settle the warrants under a limited set of conditions not entirely within the Company’s control. Therefore, the Company determined that the Pfizer Warrant should be classified as equity in the Company’s consolidated balance sheet. Voting The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings. Dividends The holders of shares of common stock are entitled to receive dividends, if and when declared by the board of directors. As of December 31, 2021, no dividends have been declared or paid on the Company’s common stock since inception. Reserved for Future Issuance The Company has reserved for future issuance the following number of shares of common stock As of December 31, 2021 and 2020: December 31, 2021 2020 Outstanding options to purchase common stock 2,899,694 1,853,841 Outstanding warrants to purchase common stock 10,926,594 12,350,293 For future issuance under the 2014 Omnibus Incentive Plan 77,631 41,079 For future issuance under the 2021 Employment Inducement Plan 1,000,000 — 14,903,919 14,245,213

Stock Warrants

Stock Warrants	12 Months Ended
	Dec. 31, 2021
Text Block [Abstract]
Stock Warrants	1 0 As of December 31, 2021 and 2020, the Company had warrants outstanding to purchase the underlying number of shares of common stock as shown in the table below. December 31, 2021 2020 2020 Warrants 8,819,904 8,842,464 2017 Warrants 1,599,645 1,599,645 2016 Warrants — 1,400,000 Pfizer Warrant 505,617 505,617 Other warrants (1) 1,428 2,567 Warrants to purchase common stock 10,926,594 12,350,293 Weighted-average exercise price per share $ 6.47 $ 9.14 (1) Other warrants are comprised of warrants issued prior to the Company’s IPO, generally in exchange for services rendered to the Company. The following table summarizes information regarding the Company’s warrants outstanding and the corresponding exercise price at December 31, 2021: Exercise Prices Shares Underlying Outstanding Warrants Expiration Date ≤ $10.00 9,325,521 May 27, 2023 > $10.00 ≤ $20.00 1,599,645 July 25, 2022 > $20.00 1,428 January 5, 10,926,594

Stock Option and Incentive Plan

Stock Option and Incentive Plans	12 Months Ended
	Dec. 31, 2021
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option and Incentive Plans	1 1 Amended and Restated 2008 Equity Incentive Plan In July 2008, the Company adopted the 2008 Equity Incentive Plan (the “Plan”). On February 26, 2013, the board of directors approved an amended and restated plan (the “Amended Plan”) under which the number of shares of common stock available for issuance was 157,143. For new awards, the period that vested awards would remain exercisable upon termination of service was reduced from ten years to two years. The board of directors also increased the number of shares of common stock available under the Company’s Amended Plan on February 24, 2014 and April 29, 2014 to 185,714 and 235,714, respectively. As of the closing of the Company’s IPO, there were no further grants made under the Amended Plan. 2014 Omnibus Incentive Plan In April 2014, the Company’s board of directors adopted the 2014 Omnibus Incentive Plan (the “2014 Plan”). The 2014 Plan was approved by the Company’s shareholders on July 3, 2014. The 2014 Plan allows for the granting of incentive and non-qualified 2021 Employment Inducement Omnibus Incentive Plan In September 2021, the Company’s board of directors adopted the 2021 Employment Inducement Omnibus Incentive Plan (the “2021 Plan”), under which the number of shares of common stock reserved for issuance was 1,000,000. The 2021 Plan allows for the granting of non-qualified stock options, restricted stock and stock unit awards, stock appreciation rights and other performance-based awards only to newly hired employees of the Company. The Company recognizes compensation expense for stock-based compensation based on the fair value of the underlying instrument. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. Stock option activity for the year ended December 31, 2021, is summarized as follows: Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Options outstanding at December 31, 2020 1,853,841 $ 14.33 Granted 1,227,500 $ 4.31 Exercised — — Expired (109,115 ) $ 45.57 Forfeited (72,532 ) $ 5.86 Options outstanding at December 31, 2021 2,899,694 $ 9.12 7.85 $ — Vested and exercisable at December 31, 2021 1,476,281 $ 12.65 6.86 $ — The fair value of each option grant is estimated on the date of the grant using the Black-Scholes option-pricing model. The weighted average grant date fair value of options granted during the years ended December 31, 2021, 2020 and 2019 was $4.31, $9.67 and $4.30, respectively. Total compensation expense recognized amounted to $3.2 million, $2.6 million and $1.4 million for the years ended December 31, 2021, 2020 and 2019, respectively. As of December 31, 2021, the total remaining unrecognized compensation cost related to unvested stock options was approximately $5.7 million which will be recognized over a weighted average period of approximately 2.38 years. The following weighted average assumptions were used to compute the fair value of stock option grants: Year Ended December 31, 2021 2020 2019 Risk free interest rate 0.83 % 1.14 % 2.35 % Expected dividend yield — — — Expected term (in years) 5.99 6.03 6.06 Expected volatility 94.5 % 94.6 % 89.7 % Expected volatility— Expected term— Risk-free interest rate— Expected dividend yield—

401k Savings Plan

401k Savings Plan	12 Months Ended
	Dec. 31, 2021
Retirement Benefits [Abstract]
401k Savings Plan	1 2 In 2010, the Company established a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code (the 401(k) Plan). The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	1 3 The Company has available approximately $275.5 million and million of million and million and The Internal Revenue Code of 1986, as amended (the “Code”) provides for a limitation of the annual use of net operating losses and other tax attributes (such as research and development tax credit carryforwards) following certain ownership changes (as defined by the Code) that could limit the Company’s ability to utilize these carryforwards. At this time, the Company has not completed a study to assess whether an ownership change under Section 382 of the Code has occurred, or whether there have been multiple ownership changes since the Company’s formation, due to the costs and complexities associated with such a study. The Company may have experienced various ownership changes, as defined by the Code, as a result of past financing transactions. Accordingly, the Company’s ability to utilize the aforementioned carryforwards may be limited. Additionally, U.S. tax laws limit the time during which these carryforwards may be applied against future taxes. Therefore, the Company may not be able to take full advantage of these carryforwards for federal or state income tax purposes. The Company’s reserves related to taxes are based on a determination of whether and how much of a tax benefit taken by the Company in its tax filings or positions is more likely than not to be realized following resolution of any potential contingencies present related to the tax benefit. For the three years ended December 31, 2021, the Company had no unrecognized tax benefits or related interest and penalties accrued. The Company has not, as yet, conducted a study of R&D credit carryforwards. This study may result in an adjustment to the Company’s R&D credit carryforwards; however, until a study is completed and any adjustment is known, no amounts are being presented as an uncertain tax position. A full valuation allowance has been provided against the Company’s R&D credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. Thus, there would be no impact to the consolidated balance sheet or statement of operations if an adjustment were required. The Company would recognize both accrued interest and penalties related to unrecognized benefits in income tax expense. The Company’s uncertain tax positions are related to years that remain subject to examination by relevant tax authorities. Since the Company is in a loss carryforward position, the Company is generally subject to examination by the U.S. federal, state and local income tax authorities for all tax years in which a loss carryforward is available. The principal components of the Company’s deferred tax assets and liabilities are as follows (in thousands): December 31, 2021 2020 Deferred tax assets: Net operating loss carryovers $ 77,431 $ 65,990 Stock-based compensation 2,457 2,265 R&D tax credits 5,031 3,833 Accrued compensation and severance 563 587 Lease liability 911 1,013 Intangible assets 88 99 Total deferred tax asset s $ 86,481 $ 73,787 Valuation allowance (85,613 ) (72,803 ) Total deferred tax assets net of valuation allowance $ 868 $ 984 Deferred tax liabilities: Right-of-use (746 ) (833 ) Depreciation (122 ) (151 ) Total deferred tax liabilities $ (868 ) $ (984 ) Net deferred tax asset (liability) $ — $ — A reconciliation of the statutory U.S. Federal rate to the company’s effective tax rate is as follows: Year Ended December 31, 2021 2020 2019 Federal income tax benefit at statutory rate (21.00 )% (21.00 )% (21.00 )% State income tax, net of federal benefit (14.41 ) (9.09 ) (15.09 ) Permanent items including change in fair value of warrants (26.27 ) (5.35 ) (21.87 ) Change in valuation allowanc e 63.08 37.88 62.56 R&D tax credits (5.89 ) (2.43 ) (4.72 ) Other 4.49 (0.01 ) 0.12 Effective income tax (benefit) expense rate 0 % 0 % 0 %

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying financial information has been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”).
Principles of Consolidation	Principles of Consolidation The Company has a wholly-owned subsidiary, ContraFect International Limited, in Scotland that establishes legal status for interactions with the European Economic Area. This subsidiary is dormant or is otherwise non-operative.
Segment and Geographic Information	Segment and Geographic Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision-making group, in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the chief executive officer. The Company and the chief decision maker view the Company’s operations and manage its business as one operating segment. The Company operates in only one geographic segment.
Significant Risks and Uncertainties	Significant Risks and Uncertainties The Company’s operations are subject to a number of factors that can affect its operating results and financial condition. Such factors include, but are not limited to: the results of clinical testing and trial activities of the Company’s products, the Company’s ability to obtain regulatory approval to market its products, and, if approved, the price of, and demand for, the Company’s products, competition from products manufactured and sold or being developed by other companies, the Company’s ability to negotiate favorable manufacturing and other agreements for its products and the Company’s ability to raise capital. The Company currently relies on a single manufacturer of exebacase drug substance and drug product, located in the United Kingdom, and there is no long-term supply agreement in place. A sustained disruption in the operations of this manufacturer or in the event the Company would need to change to a new supplier, could result in a significant delay in the ability of the Company to complete the activities needed to support a Biologics License Application for, and, if approved, commercialization of exebacase.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The Company bases estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to research and development prepaid expenses and accruals, stock-based compensation, warrant valuation and realization of net deferred income tax assets. The Company’s actual results may differ from these estimates under different assumptions or conditions. There have been no significant changes from the Company’s original estimates in any periods presented.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments which potentially subject the Company to credit risk consist primarily of cash, cash equivalents and marketable securities. The Company holds these investments in highly rated financial institutions, and, by policy, limits the amounts of credit exposure to any one financial institution. These amounts at times may exceed federally insured limits. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds. The Company has no off-balance
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents include bank demand deposits, marketable securities with maturities of three months or less at purchase, and money market funds that invest primarily in certificates of deposit, commercial paper and U.S. government and U.S. government agency obligations. Cash equivalents are reported at fair value.
Marketable Securities	Marketable Securities Marketable securities consists of investments in corporate debt securities. Management determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its marketable securities as available-for-sale Investments – Debt and Equity Securities classified as long-term assets on the consolidated balance sheets if (i) the Company has the intent and ability to hold the investments for a period of at least one year and (ii) the contractual maturity date of the investments is greater than one year. Marketable securities are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive loss in stockholders’ equity and a component of total comprehensive loss in the consolidated statements of comprehensive loss, until realized. The fair value of these securities is based on quoted prices for identical or similar assets. Realized gains and losses are included in interest income in the consolidated statement of operations on a specific-identification basis. The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, compliance with the Company’s investment policy, the severity and the duration of the impairment and changes in value subsequent to the end of the period.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company’s financial instruments consist of cash and cash equivalents, marketable securities, accounts payable, accrued liabilities and warrant liabilities. Fair value estimates of these instruments are made at a specific point in time, based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and therefore cannot be determined with precision. The fair value of the Company’s warrant liabilities is The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC Topic 820, Fair Value Measurements and Disclosures Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly. Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The Company had no liabilities classified as Level 1 or Level 2. The carrying amounts reported in the accompanying financial statements for accounts payable and accrued expenses approximate their respective fair values due to their short-term maturities. The fair value of the warrant liabilities is
Property, Office Equipment, and Leasehold Improvements	Property, Office Equipment, and Leasehold Improvements Property and equipment are recorded at cost less accumulated depreciation. Depreciation of property and equipment is provided by the straight-line method over their estimated useful lives, ranging from three Leasehold improvements are amortized on a straight-line basis over the useful life of the
Impairment of Long-lived Assets	Impairment of Long-lived Assets In accordance with ASC 360, Property, Plant, and Equipment
Research and Development Costs	Research and Development Costs Research and development costs are charged to expense as incurred and are typically made up of salaries and benefits, clinical trial activities, drug development and manufacturing costs, and third-party service fees, including for clinical research organizations and investigative sites. Costs for certain development activities, such as clinical trials, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, or information provided by vendors on their actual costs incurred. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected in the financial statements as prepaid expenses or accrued liabilities.
Stock-based Compensation	Stock-based Compensation The Company accounts for stock-based compensation in accordance with ASC 718, Compensation—Stock Compensation, non-employees, The fair value of options is calculated using the Black-Scholes option pricing model on the date of grant based on key assumptions such as stock price, risk free interest rates, expected volatility, expected term, and expected dividend yield. The Company’s estimates of these assumptions are based on historical data and judgment regarding future trends and factors.
Income Taxes	Income Taxes The Company uses the asset and liability method to calculate deferred tax assets and liabilities. Deferred taxes are recognized based on the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases using enacted tax rates expected to apply to taxable income in the years in which those differences are expected to be recovered or settled. The Company records a valuation allowance against a deferred tax asset when it is more-likely-than-not The Company is subject to federal, state and local taxes and follows a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The Company recognizes tax benefits or expenses of uncertain tax positions in the year such determination is made when the position is “more likely than not” to be sustained assuming examination by tax authorities. Management has reviewed the Company’s tax positions for all open tax years (tax years ended December 31, 2010 through December 31, 2021) and concluded that no provision for unrecognized tax benefits or expense is required in these financial statements. There are no income tax audits in progress as of December 31, 2021.
Government Contracts and Grant Agreements	Government Contracts and Grant Agreements The Company recognizes a receivable, which is included in other current assets on its consolidated balance sheet, and the related reduction in its research and development expenses when the actual reimbursable costs have been incurred and there is reasonable assurance that the Company has complied with the conditions of the applicable government contract or grant agreement and the amounts will be received. The Company recognized a reduction to its research and development expense in the amount of approximately $10.5 million, $4.2 million and $3.6 million for the years ended December 31, 2021, 2020 and 2019 respectively. The receivable for government contracts and grant agreements as of December 31, 2021 and 2020 was approximately $4.1 million and $ 1.1 million, respectively, and is included in other current assets on the consolidated balance sheet. The Company has approximately $7.7 million of committed government contract and grant agreement funding remaining as of December 31, 2021.
Net Loss per Share Applicable to Common Stockholders	Net Loss per Share Applicable to Common Stockholders Basic net loss per share applicable to common stockholders is calculated by dividing net loss applicable to common stockholders by the weighted average shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share applicable to common stockholders is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the dilutive net loss per share applicable to common stockholders’ calculation, stock options and warrants are considered to be common stock equivalents but are excluded from the calculation of diluted net loss per share applicable to common stockholders, as their effect would be anti-dilutive; therefore, basic and diluted net loss per share applicable to common stockholders were the same for all periods presented.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions, and other events and circumstances from non-owner available-for-sale
Recently Adopted Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements Fair Value Measurements On January 1, 2020, the Company adopted Accounting Standards Update No. 2018-13- Fair Value Measurement (Topic 820). Income Taxes On January 1, 2021, the Company adopted Accounting Standards Update No. 2019-12, Income Taxes (Topic 740) Recently Issued Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued a new Accounting Standards Update, Financial Instruments-Credit Losses (ASU 2016-13). 2016-13 available-for-sale In November 2021, the FASB issued a new Accounting Standards Update, Disclosure by Business Entities about Government Assistance (ASU 2021-10)

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Schedule of Marketable Securities	Marketable securities at December 31, 2021 consisted of the following (in thousands): Marketable Securities Amortized Cost Unrealized Gains Unrealized Losses Fair Current: Corporate debt $ 37,715 $ — $ (84 ) $ 37,631 Marketable securities at December 31, 2020 consisted of the following (in thousands): Marketable Securities Amortized Cost Unrealized Gains Unrealized Losses Fair Current: Corporate debt $ 27,026 $ 6 $ (27 ) $ 27,005

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Information about Company's Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following fair value hierarchy table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2021 and December 31, 2020 (in thousands): Fair Value Measurement as of December 31, 2021 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Cash equivalents $ 7,734 $ — $ — Marketable securities 37,631 — — Warrant liabilities — — 2,530 Total $ 45,365 $ — $ 2,530 Fair Value Measurement as of December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Cash equivalents $ 12,921 $ — $ — Marketable securities 27,005 — — Warrant liabilities — — 29,404 Total $ 39,926 $ — $ 29,404
Reconciliation of Company's Financial Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)	The following tables present a reconciliation of the Company’s financial liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2021, 2020 and 2019 (in thousands): Warrant liabilities Year Ended December 31, 2021 2020 2019 Balance at beginning of period $ 29,404 $ 6,069 $ 20,782 Issuance of 2020 Warrants — 31,391 — Change in fair value (26,874 ) (8,056 ) (14,713 ) Balance at end of period $ 2,530 $ 29,404 $ 6,069
2016 Warrants [Member]
Assumption Used to Determine Fair Value of Warrant Liability	The following assumptions were used in a Black-Scholes option-pricing model to determine the fair value of the warrant liability: As of December 31, 2020 Expected volatility 59.7 % Remaining contractual term (in years) 0.58 Risk-free interest rate 0.09 % Expected dividend yield — %
2017 Warrants [Member]
Assumption Used to Determine Fair Value of Warrant Liability	The following assumptions were used in a Black-Scholes option-pricing model to determine the fair value of the warrant liability: As of December 31, 2021 As of December 31, 2020 Expected volatility 56.5 % 100.1 % Remaining contractual term (in years) 0.58 1.58 Risk-free interest rate 0.19 % 0.12 % Expected dividend yield — % — %
2020 Warrants [Member]
Assumption Used to Determine Fair Value of Warrant Liability	The following assumptions were used in a Black-Scholes option-pricing model to determine the fair value of the warrant liability: As of December 31, 2021 As of December 31, 2020 Expected volatility 61.9 % 111.9 % Remaining contractual term (in years) 1.42 2.42 Risk-free interest rate 0.56 % 0.15 % Expected dividend yield — % — %

Property, Equipment, and Leas_2

Property, Equipment, and Leasehold Improvements (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule of Property, Equipment and Leasehold Improvements, at Cost	Property, equipment, and leasehold improvements, at cost, consisted of the following for the years ended December 31, 2021 and 2020 (in thousands): December 31, 2021 2020 Computer equipment $ 20 $ 20 Furniture 435 435 Lab equipment 1,864 1,864 Leasehold improvements 1,985 2,006 4,304 4,325 Less: accumulated depreciation and amortization (3,563 ) (3,415 ) $ 741 $ 910

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Payables and Accruals [Abstract]
Summary of Accrued Liabilities	Accrued liabilities consisted of the following for the years ended December 31, 2021 and 2020 (in thousands): December 31, 2021 2020 Accrued research and clinical development service fees $ 5,641 $ 801 Accrued compensation costs 2,215 2,069 Accrued professional fees 819 457 Accrued facilities operation expenses 307 173 Other accrued expenses 146 110 $ 9,128 $ 3,610

Net Loss Per Share of Common _2

Net Loss Per Share of Common Stock (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Loss Per Share for Common Stockholders	The following table sets forth the computation of basic and diluted loss per share for common stockholders (in thousands, except share and per share data): Year Ended December 31, 2021 2020 2019 Net loss applicable to common stockholders $ (20,282 ) $ (28,156 ) $ (12,794 ) Weighted average shares of common stock outstanding 36,775,950 22,763,528 8,283,509 Net loss per share of common stock—basic and diluted $ (0.55 ) $ (1.24 ) $ (1.54 )
Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted Average Shares Outstanding	The following potentially dilutive securities outstanding at December 31, 2021, 2020 and 2019 have been excluded from the computation of diluted weighted average shares outstanding, as they would have been antidilutive given the Company’s net loss: December 31, 2021 2020 2019 Options to purchase common stock 2,899,694 1,853,841 1,216,338 Warrants to purchase common stock 10,926,594 12,350,293 3,033,910 13,826,288 14,204,134 4,250,248

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Classification of Lease Liabilities	The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): December 31, Description 2021 2020 Operating lease liabilities: Current portion of lease liabilities $ 657 $ 644 Long-term portion of lease liabilities $ 2,609 $ 2,959
Summary of Future Minimum Lease Payments	As of December 31, 2021, the maturities of the Company’s operating lease liabilities were as follows (in thousands): Amount Year ending December 31: 2022 $ 693 2023 707 2024 721 2025 736 2026 750 Thereafter 702 Total lease payments 4,309 Less: Present value adjustment (1,043 ) Operating lease liabilities $ 3,266
Lease, Cost	Lease costs under the terms of the Company’s leases for the years ended December 31, 2021 and 2020 are as follows (in thousands): Year Ended December 31, 2021 2020 Operating lease cost (1) $ 616 $ 615 Variable lease costs (2) 148 126 Total lease cost $ 764 $ 741 (1) Operating lease payments included in the measurement of the Company’s lease liabilities are comprised of fixed payments according to the terms of the Company’s leases. (2) Variable lease payments consist of the Company’s utility costs billed by and paid to its landlord. Variable lease payments are presented as operating expenses in the Company’s Consolidated Statement of Operations in the same line item as expense arising from fixed lease payments and in net cash used in operating activities in the Company’s Statement of Cash Flows.

Capital Structure (Tables)

Capital Structure (Tables)	12 Months Ended
	Dec. 31, 2021
Federal Home Loan Banks [Abstract]
Summary of Common Stock Reserved for Future Issuance	The Company has reserved for future issuance the following number of shares of common stock As of December 31, 2021 and 2020: December 31, 2021 2020 Outstanding options to purchase common stock 2,899,694 1,853,841 Outstanding warrants to purchase common stock 10,926,594 12,350,293 For future issuance under the 2014 Omnibus Incentive Plan 77,631 41,079 For future issuance under the 2021 Employment Inducement Plan 1,000,000 — 14,903,919 14,245,213

Stock Warrants (Tables)

Stock Warrants (Tables)	12 Months Ended
	Dec. 31, 2021
Text Block [Abstract]
Schedule of Warrants Outstanding	As of December 31, 2021 and 2020, the Company had warrants outstanding to purchase the underlying number of shares of common stock as shown in the table below. December 31, 2021 2020 2020 Warrants 8,819,904 8,842,464 2017 Warrants 1,599,645 1,599,645 2016 Warrants — 1,400,000 Pfizer Warrant 505,617 505,617 Other warrants (1) 1,428 2,567 Warrants to purchase common stock 10,926,594 12,350,293 Weighted-average exercise price per share $ 6.47 $ 9.14 (1) Other warrants are comprised of warrants issued prior to the Company’s IPO, generally in exchange for services rendered to the Company. The following table summarizes information regarding the Company’s warrants outstanding and the corresponding exercise price at December 31, 2021: Exercise Prices Shares Underlying Outstanding Warrants Expiration Date ≤ $10.00 9,325,521 May 27, 2023 > $10.00 ≤ $20.00 1,599,645 July 25, 2022 > $20.00 1,428 January 5, 10,926,594

Stock Option and Incentive Pl_2

Stock Option and Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2021
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock Option Activity	Stock option activity for the year ended December 31, 2021, is summarized as follows: Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Options outstanding at December 31, 2020 1,853,841 $ 14.33 Granted 1,227,500 $ 4.31 Exercised — — Expired (109,115 ) $ 45.57 Forfeited (72,532 ) $ 5.86 Options outstanding at December 31, 2021 2,899,694 $ 9.12 7.85 $ — Vested and exercisable at December 31, 2021 1,476,281 $ 12.65 6.86 $ —
Assumptions to Compute Fair Value of Stock Option Grants	The following weighted average assumptions were used to compute the fair value of stock option grants: Year Ended December 31, 2021 2020 2019 Risk free interest rate 0.83 % 1.14 % 2.35 % Expected dividend yield — — — Expected term (in years) 5.99 6.03 6.06 Expected volatility 94.5 % 94.6 % 89.7 %

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Components of Deferred Tax Assets and Liabilities	The principal components of the Company’s deferred tax assets and liabilities are as follows (in thousands): December 31, 2021 2020 Deferred tax assets: Net operating loss carryovers $ 77,431 $ 65,990 Stock-based compensation 2,457 2,265 R&D tax credits 5,031 3,833 Accrued compensation and severance 563 587 Lease liability 911 1,013 Intangible assets 88 99 Total deferred tax asset s $ 86,481 $ 73,787 Valuation allowance (85,613 ) (72,803 ) Total deferred tax assets net of valuation allowance $ 868 $ 984 Deferred tax liabilities: Right-of-use (746 ) (833 ) Depreciation (122 ) (151 ) Total deferred tax liabilities $ (868 ) $ (984 ) Net deferred tax asset (liability) $ — $ —
Summary of Reconciliation of Statutory U.S. Federal Rate to Company's Effective Tax Rate	A reconciliation of the statutory U.S. Federal rate to the company’s effective tax rate is as follows: Year Ended December 31, 2021 2020 2019 Federal income tax benefit at statutory rate (21.00 )% (21.00 )% (21.00 )% State income tax, net of federal benefit (14.41 ) (9.09 ) (15.09 ) Permanent items including change in fair value of warrants (26.27 ) (5.35 ) (21.87 ) Change in valuation allowanc e 63.08 37.88 62.56 R&D tax credits (5.89 ) (2.43 ) (4.72 ) Other 4.49 (0.01 ) 0.12 Effective income tax (benefit) expense rate 0 % 0 % 0 %

Organization and Description _2

Organization and Description of Business - Additional Information (Detail) $ / shares in Units, $ in Thousands	Mar. 22, 2021USD ($)$ / sharesshares	Mar. 10, 2021USD ($)	Aug. 14, 2020USD ($)	May 27, 2020USD ($)$ / sharesshares	Dec. 18, 2019USD ($)$ / sharesshares	Dec. 12, 2019USD ($)$ / sharesshares	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Organization And Description Of Business [Line Items]
Accumulated deficit							$ 260,552	$ 240,270
Net cash used in operating activities							41,125	$ 33,187	$ 27,428
Number of shares issued | shares				11,797,752	2,565,000	3,715,000
Public offering price, per unit | $ / shares					$ 3.90	$ 2.70
Net proceeds received				$ 48,900
Gross Proceed				$ 3,000	$ 10,000	$ 13,000
Combined Net Proceeds						$ 21,300
Cash Cash Equivalents And Marketable Securities							$ 54,300
BARDA Contract [Member]
Organization And Description Of Business [Line Items]
Total funding receives in future		$ 86,800
Contract period of performance		6 years
BARDA Contract [Member] | Additional BARDA Funding [Member]
Organization And Description Of Business [Line Items]
Total funding receives in future		$ 77,000
BARDA Contract [Member] | Base Period BARDA Funding [Member]
Organization And Description Of Business [Line Items]
Total funding receives in future		$ 9,800
Pfizer Warrants [Member]
Organization And Description Of Business [Line Items]
Warrants to purchase shares of common stock | shares				505,617
Warrant exercise price per share | $ / shares				$ 4.90
Follow-on Offering [Member]
Organization And Description Of Business [Line Items]
Number of shares issued | shares				11,797,752
Warrants to purchase shares of common stock | shares				8,848,314
Warrant exercise price per share | $ / shares				$ 4.90
Public offering price, per unit | $ / shares				$ 4.45
Net proceeds received				$ 48,900
Stock issued during period, value			$ 150,000
Conversion ratio of common stock				0.75			0.75	0.75
Private Placement [Member]
Organization And Description Of Business [Line Items]
Public offering price, per unit | $ / shares				$ 4.45		$ 2.70
Issuance of securities in private placement, Shares | shares				674,156		1,111,111
IPO [Member]
Organization And Description Of Business [Line Items]
Conversion ratio of common stock				0.75
Over-Allotment Option [Member]
Organization And Description Of Business [Line Items]
Number of shares issued | shares	11,500,000
Public offering price, per unit | $ / shares	$ 5
Proceeds from initial public offer	$ 53,800

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021USD ($)Segment	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segment | Segment	1
Number of geographic segment | Segment	1
Maturity period of highly liquid investments	three months or less
Realized gains or losses on marketable securities	$ 0	$ 9,609
Number of securities in unrealized loss position for more than 12 months	0	0
Impairment of long-lived assets	$ 0	$ 0
Provision for unrecognized tax benefits or expense	0
Grants receivable recognized	10,500,000	4,200,000	$ 3,600,000
Grants receivable	4,100,000	$ 1,100,000
Grants remaining to be awarded	$ 7,700,000
Earliest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Tax position for all open tax years	2010
Latest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Tax position for all open tax years	2021
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	5 years
Level 1 [Member]
Summary Of Significant Accounting Policies [Line Items]
Liabilities	$ 0
Level 2 [Member]
Summary Of Significant Accounting Policies [Line Items]
Liabilities	$ 0

Marketable Securities - Schedul

Marketable Securities - Schedule of Marketable Securities (Detail) - Corporate Debt [Member] - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities, Amortized Cost	$ 37,715	$ 27,026
Marketable Securities, Unrealized Gains	0	6
Marketable Securities, Unrealized Losses	(84)	(27)
Marketable Securities, Fair Value	$ 37,631	$ 27,005

Marketable Securities - Additio

Marketable Securities - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021USD ($)Security	Dec. 31, 2020USD ($)Security
Marketable Securities [Abstract]
Marketable securities	$ 0	$ 0
Maturity period classified current investments	less than one year
Number of securities in unrealized loss position for less than one year | Security	23	15
Aggregate fair value of debt securities	$ 37,631	$ 18,116

Fair Value Measurements - Infor

Fair Value Measurements - Information about Company's Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 37,631	$ 27,005
Warrant liabilities	(2,530)	(29,404)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	7,734	12,921
Marketable securities	37,631	27,005
Total assets (liabilities)	45,365	39,926
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrant liabilities	2,530	29,404
Total assets (liabilities)	$ 2,530	$ 29,404

Fair Value Measurements - Assum

Fair Value Measurements - Assumption Used to Determine Fair Value of Warrant Liability (Detail)	Dec. 31, 2021yr	Dec. 31, 2020yr
2016 Warrants [Member] | Expected Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability		0.597
2016 Warrants [Member] | Remaining Contractual term (in years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability		0.58
2016 Warrants [Member] | Risk-free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability		0.0009
2017 Warrants [Member] | Expected Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	0.565	1.001
2017 Warrants [Member] | Remaining Contractual term (in years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	0.58	1.58
2017 Warrants [Member] | Risk-free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	0.0019	0.0012
2020 Warrants [Member] | Expected Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	0.619	1.119
2020 Warrants [Member] | Remaining Contractual term (in years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	1.42	2.42
2020 Warrants [Member] | Risk-free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrant liability	0.0056	0.0015

Fair Value Measurements - Recon

Fair Value Measurements - Reconciliation of Company's Financial Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3) (Detail) - Warrant Liabilities [Member] - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 29,404	$ 6,069	$ 20,782
Issuance of 2020 warrants		31,391
Change in fair value	(26,874)	(8,056)	(14,713)
Balance at end of period	$ 2,530	$ 29,404	$ 6,069

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail)	Dec. 31, 2021	Jul. 27, 2021
2016 Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants And Rights Expiry Date	Jul. 27, 2021	Jul. 27, 2021

Property, Equipment, and Leas_3

Property, Equipment, and Leasehold Improvements - Schedule of Property, Equipment and Leasehold Improvements, at Cost (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, equipment, and leasehold improvements, at cost, gross	$ 4,304	$ 4,325
Less: accumulated depreciation and amortization	(3,563)	(3,415)
Property, equipment, and leasehold improvements, at cost, net	741	910
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, equipment, and leasehold improvements, at cost, gross	20	20
Furniture [Member]
Property, Plant and Equipment [Line Items]
Property, equipment, and leasehold improvements, at cost, gross	435	435
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, equipment, and leasehold improvements, at cost, gross	1,864	1,864
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, equipment, and leasehold improvements, at cost, gross	$ 1,985	$ 2,006

Property, Equipment, and Leas_4

Property, Equipment, and Leasehold Improvements - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 148	$ 168	$ 169

Accrued Liabilities - Summary o

Accrued Liabilities - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued research and clinical development service fees	$ 5,641	$ 801
Accrued compensation costs	2,215	2,069
Accrued professional fees	819	457
Accrued facilities operation expenses	307	173
Other accrued expenses	146	110
Total accrued expenses	$ 9,128	$ 3,610

Net Loss Per Share of Common _3

Net Loss Per Share of Common Stock - Schedule of Computation of Basic and Diluted Loss Per Share for Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Net loss applicable to common stockholders	$ (20,282)	$ (28,156)	$ (12,794)
Weighted average shares of common stock outstanding	36,775,950	22,763,528	8,283,509
Net loss per share of common stock—basic and diluted	$ (0.55)	$ (1.24)	$ (1.54)

Net Loss Per Share of Common _4

Net Loss Per Share of Common Stock - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted Average Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares	13,826,288	14,204,134	4,250,248
Employee Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares	2,899,694	1,853,841	1,216,338
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares	10,926,594	12,350,293	3,033,910

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended			12 Months Ended
	Jan. 31, 2012ft²ExtensionOptions	Dec. 31, 2011ExtensionOptions	Dec. 31, 2010	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Jan. 01, 2019
Loss Contingencies [Line Items]
Non-cancellable operating lease, expiration date	2027-12		2025-12
Extended lease agreement, date		2027-12
Number of lease extension options | ExtensionOptions	2	2
Lease renewal termination period	5 years	5 years
Area of space relinquished from lease agreement | ft²	10,912
Milestone payment				$ 810,000
Operating lease, remaining lease term							9 years
Operating lease, discount rate, percent							9.93%
Rockefeller University [Member]
Loss Contingencies [Line Items]
Annual maintenance fees payable in 2018				200,000	$ 200,000	$ 200,000
Annual maintenance fees payable after 2018				$ 200,000	$ 200,000	$ 200,000
Percentage of royalty on net sales				5.00%	5.00%	5.00%
Milestone payment						$ 430,000
Regulatory milestone payment				$ 5,000,000	$ 5,000,000	$ 5,000,000
Royalty or sublicense payment				$ 0	$ 0
License agreement termination notice period				60 days
Period of termination after first commercial sale of first licensed product				10 years
License agreement termination description				Each license agreement terminates upon the later of (i) the expiration or abandonment of the last licensed patent under the license agreement to expire or become abandoned, or (ii) 10 years after the first commercial sale of the first licensed product. The Rockefeller University may terminate any license agreement in the event of a breach of such agreement by the Company or if the Company challenges the validity or enforceability of the underlying patent rights. The Company may terminate any license agreement at any time on 60 days’ notice.

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Classification of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Operating lease liabilities:
Current portion of lease liabilities	$ 657	$ 644
Long-term portion of lease liabilities	$ 2,609	$ 2,959

Commitments and Contingencies_3

Commitments and Contingencies - Maturities Of Operating Lease Liabilities (Detail) $ in Thousands	Dec. 31, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
2022	$ 693
2023	707
2024	721
2025	736
2026	750
Thereafter	702
Total lease payments	4,309
Less: Present value adjustment	(1,043)
Operating lease liabilities	$ 3,266

Commitments and Contingencies_4

Commitments and Contingencies - Lease Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disclosure of Lease of Cost [Abstract]
Operating lease cost	$ 616	$ 615
Variable lease costs	148	126
Total lease cost	$ 764	$ 741

Capital Structure - Additional

Capital Structure - Additional Information (Detail)	Mar. 22, 2021USD ($)$ / sharesshares	May 27, 2020USD ($)$ / sharesshares	Dec. 18, 2019USD ($)$ / sharesshares	Dec. 12, 2019USD ($)$ / sharesshares	Jul. 25, 2017USD ($)	Jul. 27, 2016USD ($)	Dec. 31, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares	Jul. 27, 2021
Class of Stock [Line Items]
Common stock, shares authorized | shares							125,000,000
Common stock, par value | $ / shares							$ 0.0001	$ 0.0001
Number of shares issued | shares		11,797,752	2,565,000	3,715,000
Public offering price, per unit | $ / shares			$ 3.90	$ 2.70
Net proceeds received		$ 48,900,000
Gross Proceed		$ 3,000,000	$ 10,000,000	$ 13,000,000
Dividends declared or paid							$ 0
Combined Net Proceeds				$ 21,300,000
Issuance costs allocated to warrants								$ 2,175,000
Common stock, voting rights							The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings.
Issuance of common stock for exercise of warrants, Shares | shares							22,560	5,850
2016 Warrants [Member]
Class of Stock [Line Items]
Warrants And Rights Expiry Date							Jul. 27, 2021		Jul. 27, 2021
Class Of Warrant Or Rights Exercisable | shares							0
Private Placement [Member]
Class of Stock [Line Items]
Public offering price, per unit | $ / shares		$ 4.45		$ 2.70
Issuance of securities in private placement, Shares | shares		674,156		1,111,111
Follow-on Offering [Member]
Class of Stock [Line Items]
Number of shares issued | shares		11,797,752
Public offering price, per unit | $ / shares		$ 4.45
Net proceeds received		$ 48,900,000
Warrants to purchase shares of common stock | shares		8,848,314
Warrant exercise price per share | $ / shares		$ 4.90
Conversion ratio of common stock		0.75					0.75	0.75
Follow-on Offering [Member] | 2016 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants						$ 18,600,000
Issuance costs allocated to warrants						$ 1,600,000
Follow-on Offering [Member] | 2017 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants					$ 12,400,000
Issuance costs allocated to warrants					$ 900,000
Follow-on Offering [Member] | 2020 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants		$ 31,400,000
Issuance costs allocated to warrants		$ 2,200,000
Over-Allotment Option [Member]
Class of Stock [Line Items]
Number of shares issued | shares	11,500,000
Public offering price, per unit | $ / shares	$ 5
Exercise price per common share | $ / shares	$ 5
Proceeds from Issuance Initial Public Offering	$ 53,800,000
Pfizer Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock | shares		505,617
Warrant exercise price per share | $ / shares		$ 4.90

Capital Structure - Summary of

Capital Structure - Summary of Common Stock Reserved for Future Issuance (Detail) - shares	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common Stock reserved for future issuance	14,903,919	14,245,213
Two Thousand Fourteen Omnibus Incentive Plan [Member]
Class of Stock [Line Items]
Common Stock reserved for future issuance	77,631	41,079
Two Thousand Twenty One Employment Inducement Plan [Member]
Class of Stock [Line Items]
Common Stock reserved for future issuance	1,000,000
Stock Options [Member]
Class of Stock [Line Items]
Common Stock reserved for future issuance	2,899,694	1,853,841
Warrants [Member]
Class of Stock [Line Items]
Common Stock reserved for future issuance	10,926,594	12,350,293

Stock Warrants - Schedule of Wa

Stock Warrants - Schedule of Warrants Outstanding (Detail) - $ / shares		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	May 27, 2020
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		10,926,594	12,350,293
Weighted-average exercise price per share		$ 6.47	$ 9.14
Pfizer Warrants [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		505,617	505,617
Exercise Prices				$ 4.90
Other Warrants [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants	[1]	1,428	2,567
Exercise Price Less Than or Equal to $10.00 [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		9,325,521
Expiration Start Date		May 27, 2023
Exercise Price Greater Than $10.00 Lesser Than Equal To $20.00 [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		1,599,645
Expiration Start Date		Jul. 25, 2022
Exercise Price Greater Than or Equal to $ 20.00 [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		1,428
Expiration Start Date		Jan. 5, 2022
Minimum [Member] | Exercise Price Less Than or Equal to $10.00 [Member]
Class of Warrant or Right [Line Items]
Exercise Prices		$ 10
Minimum [Member] | Exercise Price Greater Than $10.00 Lesser Than Equal To $20.00 [Member]
Class of Warrant or Right [Line Items]
Exercise Prices		10
Minimum [Member] | Exercise Price Greater Than or Equal to $ 20.00 [Member]
Class of Warrant or Right [Line Items]
Exercise Prices		20
Maximum [Member] | Exercise Price Greater Than $10.00 Lesser Than Equal To $20.00 [Member]
Class of Warrant or Right [Line Items]
Exercise Prices		$ 20
2016 Warrants [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		0	1,400,000
2017 Warrants [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		1,599,645	1,599,645
2020 Warrants [Member]
Class of Warrant or Right [Line Items]
Shares Underlying Outstanding Warrants		8,819,904	8,842,464
[1]	Other warrants are comprised of warrants issued prior to the Company’s IPO, generally in exchange for services rendered to the Company.

Stock Option and Incentive Pl_3

Stock Option and Incentive Plans - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2021	Dec. 31, 2015	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2021	Jul. 28, 2014	Apr. 29, 2014	Feb. 24, 2014	Feb. 26, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan	14,903,919		14,903,919	14,245,213
Weighted average grant date fair value of options			$ 4.31	$ 9.67	$ 4.30
Unrecognized compensation cost related to unvested stock options	$ 5.7		$ 5.7
Weighted average period of unvested stock options			2 years 4 months 17 days
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized			$ 3.2	$ 2.6	$ 1.4
Amended and Restated 2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan										157,143
Termination of service, Period			2 years
2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan								235,714	185,714
Termination of service, Period			10 years
2014 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan							57,143
Number of additional shares increases of common stock reserved pursuant to the plan	2,695,373
2014 Omnibus Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase of plan, percentage of common stock shares outstanding		4.00%
2021 Employment Inducement Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan						1,000,000

Stock Option and Incentive Pl_4

Stock Option and Incentive Plans - Summary of Stock Option Activity (Detail)	12 Months Ended
	Dec. 31, 2021USD ($)$ / sharesshares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Options, Options outstanding, Beginning balance | shares	1,853,841
Number of Options, Granted | shares	1,227,500
Number of Options, Exercised | shares	0
Number of Options, Expired | shares	(109,115)
Number of Options, Forfeited | shares	(72,532)
Number of Options, Options outstanding, Ending balance | shares	2,899,694
Number of Options, Vested and exercisable, Ending Balance | shares	1,476,281
Weighted Average Exercise Price, Options outstanding, Beginning balance | $ / shares	$ 14.33
Weighted Average Exercise Price, Granted | $ / shares	4.31
Weighted Average Exercise Price, Exercised | $ / shares	0
Weighted Average Exercise Price, Expired | $ / shares	45.57
Weighted Average Exercise Price, Forfeited | $ / shares	5.86
Weighted Average Exercise Price, Options outstanding, Ending balance | $ / shares	9.12
Weighted Average Exercise Price, Vested and exercisable, Ending balance | $ / shares	$ 12.65
Weighted Average Remaining Contractual Life (in years), Options outstanding	7 years 10 months 6 days
Weighted Average Remaining Contractual Life (in years), Vested and exercisable	6 years 10 months 9 days
Aggregate Intrinsic value, Options outstanding | $	$ 0
Aggregate Intrinsic value, Vested and exercisable | $	$ 0

Stock Option and Incentive Pl_5

Stock Option and Incentive Plans - Assumptions to Compute Fair Value of Stock Option Grants (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Risk free interest rate	0.83%	1.14%	2.35%
Expected dividend yield	$ 0	$ 0	$ 0
Expected term (in years)	5 years 11 months 26 days	6 years 10 days	6 years 21 days
Expected volatility	94.50%	94.60%	89.70%

401k Savings Plan - Additional

401k Savings Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
401k Savings Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Expense for matching contributions	$ 0.2	$ 0.1	$ 0.1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Contingency [Line Items]
Unused operating loss carryforwards for federal tax purposes	$ 275,500,000
Unused operating loss carryforwards for state tax purposes	$ 293,900,000
Net operating loss carryforwards, expiration year	2028
Deferred tax valuation allowance	$ 85,613,000	$ 72,803,000
Increase (decrease) in valuation allowance	12,800,000	$ 10,700,000
Unrecognized tax benefits	0
Unrecognized interest	0
Unrecognized penalties accrued	$ 0
Research and development credit carry forwards expiration year	2031

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating loss carryovers	$ 77,431	$ 65,990
Stock-based compensation	2,457	2,265
R&D tax credits	5,031	3,833
Accrued compensation and severance	563	587
Lease liability	911	1,013
Intangible assets	88	99
Total deferred tax assets	86,481	73,787
Valuation allowance	(85,613)	(72,803)
Total deferred tax assets net of valuation allowance	868	984
Deferred tax liabilities:
Right-of-use asset	(746)	(833)
Depreciation	(122)	(151)
Total deferred tax liabilities	(868)	(984)
Net deferred tax asset (liability)	$ 0	$ 0

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Statutory U.S. Federal Rate to Company's Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal income tax benefit at statutory rate	(21.00%)	(21.00%)	(21.00%)
State income tax, net of federal benefit	(14.41%)	(9.09%)	(15.09%)
Permanent items including change in fair value of warrants	(26.27%)	(5.35%)	(21.87%)
Change in valuation allowance	63.08%	37.88%	62.56%
R&D tax credits	(5.89%)	(2.43%)	(4.72%)
Other	4.49%	(0.01%)	0.12%
Effective income tax (benefit) expense rate	0.00%	0.00%	0.00%