Enliven Therapeutics (ELVN) 10-Q 14 Aug 20 2020 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Cover [Abstract]
Entity Registrant Name	IMARA INC.
Document Type	10-Q
Trading Symbol	IMRA
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		17,324,736
Amendment Flag	false
Entity Central Index Key	0001672619
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Jun. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common stock, par value $0.001 per share
Security Exchange Name	NASDAQ
Entity File Number	001-39247
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-1523849
Entity Address, Address Line One	116 Huntington Avenue
Entity Address, Address Line Two	6th Floor
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02116
City Area Code	617
Local Phone Number	206-2020
Document Quarterly Report	true
Document Transition Report	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 54,651	$ 4,936
Short-term investments	51,624	23,971
Prepaid expenses and other current assets	4,318	1,717
Total current assets	110,593	30,624
Property and equipment, net	400	442
Other assets	324	2,232
Total assets	111,317	33,298
Current liabilities:
Accounts payable	1,669	1,658
Accrued expenses and other current liabilities	3,179	2,540
Total current liabilities	4,848	4,198
Deferred rent	173	184
Total liabilities	5,021	4,382
Commitments and contingencies (Note 7)
Convertible preferred stock, $0.001 par value per share; no shares authorized, issued or outstanding as of June 30, 2020; 70,378,661 shares authorized and 60,533,313 shares issued and outstanding as of December 31, 2019		77,764
Stockholders’ equity (deficit):
Preferred stock, $0.001 par value per share; 10,000,000 shares authorized; no shares issued or outstanding as of June 30, 2020; no shares authorized, issued or outstanding as of December 31, 2019
Common stock, $0.001 par value per share; 200,000,000 and 100,000,000 shares authorized as of June 30, 2020 and December 31, 2019, respectively; 17,324,736 and 702,510 shares issued and outstanding as of June 30, 2020 and December 31, 2019, respectively	18	1
Additional paid-in capital	178,402	5,872
Accumulated other comprehensive income	48	32
Accumulated deficit	(72,172)	(54,753)
Total stockholders’ equity (deficit)	106,296	(48,848)
Total liabilities, convertible preferred stock and stockholders’ equity (deficit)	$ 111,317	$ 33,298

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Convertible preferred stock, par value	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	0	70,378,661
Convertible preferred stock, shares issued	0	60,533,313
Convertible preferred stock, shares outstanding	0	60,533,313
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	100,000,000
Common stock, shares issued	17,324,736	702,510
Common stock, shares outstanding	17,324,736	702,510

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating expenses:
Research and development	$ 7,869	$ 4,366	$ 13,662	$ 7,926
General and administrative	2,433	1,191	3,992	1,825
Total operating expenses	10,302	5,557	17,654	9,751
Loss from operations	(10,302)	(5,557)	(17,654)	(9,751)
Total other income:
Interest income	110	160	242	160
Other expense	(12)		(7)
Total other income (net)	98	160	235	160
Net loss	(10,204)	(5,397)	(17,419)	(9,591)
Accretion of Series B convertible preferred stock			(7,858)
Net loss attributable to common stockholders—basic and diluted	$ (10,204)	$ (5,397)	$ (25,277)	$ (9,591)
Weighted-average common shares outstanding—basic and diluted	17,194,795	702,510	10,344,077	702,510
Net loss per share attributable to common stockholders—basic and diluted	$ (0.59)	$ (7.68)	$ (2.44)	$ (13.65)
Comprehensive loss:
Net loss	$ (10,204)	$ (5,397)	$ (17,419)	$ (9,591)
Other comprehensive income:
Unrealized gains on investments (net)	64		16
Comprehensive loss	$ (10,140)	$ (5,397)	$ (17,403)	$ (9,591)

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' (DEFICIT) EQUITY (Unaudited) - USD ($) $ in Thousands	Total	CONVERTIBLE PREFERRED STOCK SERIES SEED	CONVERTIBLE PREFERRED STOCK SERIES A	CONVERTIBLE PREFERRED STOCK SERIES B	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	ACCUMULATED DEFICIT
Beginning balance at Dec. 31, 2018	$ (26,316)				$ 1	$ 4,973		$ (31,290)
Beginning balance, shares at Dec. 31, 2018					702,510
Beginning balance, convertible preferred stock at Dec. 31, 2018		$ 1,460	$ 30,729
Beginning balance, convertible preferred stock, shares at Dec. 31, 2018		2,712,960	31,499,040
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge				$ 43,825
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge, shares				25,316,663
Stock-based compensation expense	95					95
Net loss	(4,194)							(4,194)
Ending balance at Mar. 31, 2019	(30,415)				$ 1	5,068		(35,484)
Ending balance, shares at Mar. 31, 2019					702,510
Ending balance, convertible preferred stock at Mar. 31, 2019		$ 1,460	$ 30,729	$ 43,825
Ending balance, convertible preferred stock, shares at Mar. 31, 2019		2,712,960	31,499,040	25,316,663
Beginning balance at Dec. 31, 2018	(26,316)				$ 1	4,973		(31,290)
Beginning balance, shares at Dec. 31, 2018					702,510
Beginning balance, convertible preferred stock at Dec. 31, 2018		$ 1,460	$ 30,729
Beginning balance, convertible preferred stock, shares at Dec. 31, 2018		2,712,960	31,499,040
Net loss	(9,591)
Ending balance at Jun. 30, 2019	(35,615)				$ 1	5,265		(40,881)
Ending balance, shares at Jun. 30, 2019					702,510
Ending balance, convertible preferred stock at Jun. 30, 2019		$ 1,460	$ 30,729	$ 45,575
Ending balance, convertible preferred stock, shares at Jun. 30, 2019		2,712,960	31,499,040	26,321,313
Beginning balance at Mar. 31, 2019	(30,415)				$ 1	5,068		(35,484)
Beginning balance, shares at Mar. 31, 2019					702,510
Beginning balance, convertible preferred stock at Mar. 31, 2019		$ 1,460	$ 30,729	$ 43,825
Beginning balance, convertible preferred stock, shares at Mar. 31, 2019		2,712,960	31,499,040	25,316,663
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge				$ 1,750
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge, shares				1,004,650
Stock-based compensation expense	197					197
Net loss	(5,397)							(5,397)
Ending balance at Jun. 30, 2019	(35,615)				$ 1	5,265		(40,881)
Ending balance, shares at Jun. 30, 2019					702,510
Ending balance, convertible preferred stock at Jun. 30, 2019		$ 1,460	$ 30,729	$ 45,575
Ending balance, convertible preferred stock, shares at Jun. 30, 2019		2,712,960	31,499,040	26,321,313
Beginning balance at Dec. 31, 2019	(48,848)				$ 1	5,872	$ 32	(54,753)
Beginning balance, shares at Dec. 31, 2019					702,510
Beginning balance, convertible preferred stock at Dec. 31, 2019	$ 77,764	$ 1,460	$ 30,729	$ 45,575
Beginning balance, convertible preferred stock, shares at Dec. 31, 2019	60,533,313	2,712,960	31,499,040	26,321,313
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge	$ 7,858			$ 9,271		7,858
Issuance of Series B convertible preferred stock, net of issuance costs and beneficial conversion charge, shares				9,845,348
Accretion of Series B converted preferred stock				$ 7,858
Accretion of Series B converted preferred stock	(7,858)					(7,858)
Conversion of convertible preferred stock into common stock	94,893	$ (1,460)	$ (30,729)	$ (62,704)	$ 11	94,882
Conversion of convertible preferred stock into common stock, shares		(2,712,960)	(31,499,040)	(36,166,661)	11,172,955
Initial public offering, net of underwriting discounts, commissions and offering costs	66,052				$ 5	66,047
Initial public offering, net of underwriting discounts, commissions and offering costs, shares					4,700,000
Stock-based compensation expense	360					360
Unrealized gain (loss) on investments	(48)						(48)
Net loss	(7,215)							(7,215)
Ending balance at Mar. 31, 2020	105,194				$ 17	167,161	(16)	(61,968)
Ending balance, shares at Mar. 31, 2020					16,575,465
Beginning balance at Dec. 31, 2019	(48,848)				$ 1	5,872	32	(54,753)
Beginning balance, shares at Dec. 31, 2019					702,510
Beginning balance, convertible preferred stock at Dec. 31, 2019	$ 77,764	$ 1,460	$ 30,729	$ 45,575
Beginning balance, convertible preferred stock, shares at Dec. 31, 2019	60,533,313	2,712,960	31,499,040	26,321,313
Exercise of stock options, shares	44,271
Net loss	$ (17,419)
Ending balance at Jun. 30, 2020	$ 106,296				$ 18	178,402	48	(72,172)
Ending balance, shares at Jun. 30, 2020					17,324,736
Ending balance, convertible preferred stock, shares at Jun. 30, 2020	0
Beginning balance at Mar. 31, 2020	$ 105,194				$ 17	167,161	(16)	(61,968)
Beginning balance, shares at Mar. 31, 2020					16,575,465
Initial public offering, net of underwriting discounts, commissions and offering costs	10,474				$ 1	10,473
Initial public offering, net of underwriting discounts, commissions and offering costs, shares					705,000
Exercise of stock options	218					218
Exercise of stock options, shares					44,271
Stock-based compensation expense	550					550
Unrealized gain (loss) on investments	64						64
Net loss	(10,204)							(10,204)
Ending balance at Jun. 30, 2020	$ 106,296				$ 18	$ 178,402	$ 48	$ (72,172)
Ending balance, shares at Jun. 30, 2020					17,324,736
Ending balance, convertible preferred stock, shares at Jun. 30, 2020	0

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' (DEFICIT) EQUITY (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2019
Convertible preferred stock, par value	$ 0.001
Common stock, par value	$ 0.001
Initial Public Offering
Underwriting discounts, commissions and offering costs	$ 17	$ 3,885
CONVERTIBLE PREFERRED STOCK SERIES SEED
Convertible preferred stock, par value	$ 0.001	$ 0.001	$ 0.001	$ 0.001
CONVERTIBLE PREFERRED STOCK SERIES A
Convertible preferred stock, par value	0.001	0.001	0.001	0.001
CONVERTIBLE PREFERRED STOCK SERIES B
Convertible preferred stock, par value	0.001	$ 0.001	$ 0.001	0.001
Stock issuance costs		$ 20	$ 274
COMMON STOCK
Common stock, par value	$ 0.001	$ 0.001	$ 0.001	$ 0.001

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net loss	$ (17,419)	$ (9,591)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	910	292
Depreciation expense	49
Amortization and accretion on investments	(8)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(2,601)	(114)
Accounts payable	(112)	764
Accrued expenses and other current liabilities	469	1,062
Deferred rent	(11)	32
Other assets	(60)
Net cash used in operating activities	(18,783)	(7,555)
Cash flows from investing activities:
Proceeds from maturities and sales of short-term investments	14,200
Purchases of short-term investments	(41,829)
Purchases of property and equipment	(22)	(81)
Net cash used in investing activities	(27,651)	(81)
Cash flows from financing activities:
Proceeds from issuance of Series B convertible preferred stock, net of issuance costs	17,150	45,575
Proceeds from initial public offering, net of underwriting discounts and commissions	80,427
Payment of issuance costs	(1,646)
Proceeds from exercise of options	218
Net cash provided by financing activities	96,149	45,575
Net increase in cash, cash equivalents and restricted cash	49,715	37,939
Cash, cash equivalents and restricted cash, beginning of period	5,024	7,382
Cash, cash equivalents and restricted cash, end of period	54,739	45,321
Supplemental disclosure of non-cash investing and financing activities:
Conversion of convertible preferred stock into common stock	94,893
Accretion of redeemable convertible preferred stock to redemption value	7,858
Reclassification of deferred offering costs from other assets to additional paid-in capital	2,144
Deferred offering costs included in accounts payable and accrued expenses	369	$ 55
Property and equipment purchases included in accrued expenses	15
Unrealized gain on investments	$ 16

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Statement Of Cash Flows [Abstract]
Cash and cash equivalents	$ 54,651	$ 45,233
Restricted cash (included in other assets)	88	88
Total cash, cash equivalents and restricted cash	$ 54,739	$ 45,321

Nature of the Business

Nature of the Business	6 Months Ended
	Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of the Business	1. Nature of the Business IMARA Inc. (“IMARA” or the “Company”) is a clinical-stage biopharmaceutical company dedicated to developing and commercializing novel therapeutics to treat patients suffering from rare inherited genetic disorders of hemoglobin, known as hemoglobinopathies, which have significant unmet medical need. The Company was incorporated in January 2016 under the laws of the State of Delaware, and its principal offices are in Boston, Massachusetts. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including but not limited to, risks associated with completing preclinical studies and clinical trials, receiving regulatory approvals for product candidates, development by competitors of new biopharmaceutical products, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Such risks and uncertainties may be amplified by the COVID-19 pandemic and its impact on the Company’s business and the global economy. The Company’s sole product candidate currently under development, IMR-687, as well as any other product candidates the Company may develop, will require significant additional research and development efforts, including preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will realize revenue from product sales. In February 2020, the Company effected a 1-for-6.299 reverse stock split of the Company’s issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratios for each of the Company’s outstanding series of preferred stock. All share and per share amounts in the unaudited condensed consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to give effect to the reverse stock split, including reclassifying an amount equal to the change in par value of common stock to additional paid-in capital. On February 25, 2020, the Company issued and sold 1,562,994‬ shares of Series B convertible preferred stock (“Series B Preferred Stock”), at a price of $10.9722 per share, upon a waiver of specified milestone conditions from the holders of a majority of the shares then held by holders of Series B Preferred Stock, and raised approximately $17.1 million in net proceeds after deducting less than $0.1 million of issuance costs. On March 16, 2020, the Company completed an initial public offering (“IPO”) of its common stock and issued and sold 4,700,000 shares of common stock at a public offering price of $16.00 per share, resulting in gross proceeds of $75.2 million. On April 13, 2020, the Company issued and sold an additional 705,000 shares of common stock pursuant to the exercise of the underwriters’ option to purchase additional shares for aggregate gross proceeds of $11.3 million. Inclusive of the exercise by the underwriters of their option to purchase additional shares, the Company received approximately $76.5 million in net proceeds from the IPO after deducting $10.0 million of underwriting discounts and commissions and offering expenses. Upon the closing of the IPO, all 70,378,661 shares of outstanding preferred stock automatically converted into 11,172,955 shares of common stock. Upon conversion of the convertible preferred stock, the Company reclassified the carrying value of the convertible preferred stock to common stock and additional paid-in capital. Liquidity The Company has incurred recurring negative cash flows since inception and has funded its operations primarily from the sale of convertible preferred stock and proceeds from the IPO. As of June 30, 2020, the Company had cash, cash equivalents, and investments of $106.3 million and an accumulated deficit of approximately $72.2 million. The Company expects its operating losses and negative operating cash flows to continue into the foreseeable future as it continues to expand its research and development efforts. The Company believes its cash, cash equivalents and investments as of June 30, 2020 will be sufficient to fund its operating expenses and capital expenditure requirements for at least twelve months from the date of filing this Quarterly Report on Form 10-Q. The Company will need additional funding to support its planned operating activities. There can be no assurances, however, that the current operating plan will be achieved or that additional funding will be available on terms acceptable to the Company, or at all. If the Company is unable to obtain sufficient funding, it could be required to delay its development efforts, limit activities and reduce research and development costs, which could adversely affect its business prospects.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of presentation The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and as amended by Accounting Standards Updates of the Financial Accounting Standards Board (“FASB”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted from this report, as is permitted by such rules and regulations. Accordingly, these financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2019 and notes thereto, included in the Company’s Registration Statement on Form S-1/A, filed with the Securities Exchange Commission (“SEC”) on March 10, 2020. The unaudited condensed consolidated interim financial statements have been prepared on the same basis as the audited financial statements. In the opinion of the Company’s management, the accompanying unaudited condensed consolidated interim financial statements contain all adjustments which are necessary to present fairly the Company’s financial position as of June 30, 2020, the results of its operations for the three and six months ended June 30, 2020 and 2019 and cash flows for the six months ended June 30, 2020 and 2019. Such adjustments are of a normal and recurring nature. The results for the three and six months ended June 30, 2020 are not necessarily indicative of the results for the year ending December 31, 2020, or for any future period. Principles of Consolidation The accompanying unaudited condensed consolidated financial statements of the Company include the accounts of its wholly owned subsidiaries, IMARA Security Corporation and IMARA E.U. Limited. All intercompany transactions and balances have been eliminated in consolidation. Summary of Significant Accounting Policies The significant accounting policies and estimates used in the preparation of the accompanying unaudited condensed consolidated financial statements are described in the Company’s audited consolidated financial statements for the year ended December 31, 2019 included in the Company’s Registration Statement on Form S-1/A filed with the SEC on March 10, 2020. There have been no material changes in the Company’s significant accounting policies during the three and six months ended June 30, 2020. Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these unaudited condensed consolidated financial statements include, but are not limited to, accrued research and development expenses, stock-based compensation expense, the fair value of the common stock and the intrinsic value of the beneficial conversation feature present in the second tranche of the Series B Preferred Stock issued in February of 2020. Actual results could differ materially from those estimates. Segments Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one operating segment. The Company’s chief operating decision maker, its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purpose of allocating resources. All of the Company’s long-lived assets are held in the United States. Deferred Offering Costs The Company capitalizes certain legal, professional, accounting and other third-party fees that are directly associated with in-process equity issuances as deferred offering costs until such equity issuances are consummated. After consummation of the equity issuance, these costs are recorded as a reduction in the capitalized amount associated with the equity issuance. Should the equity issuance be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the unaudited condensed consolidated statement of operations and comprehensive loss. Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity (deficit) that are excluded from net loss. The Company’s comprehensive loss was equal to net loss for the three and six months ended June 30, 2019. For the three and six month period ended June 30, 2020, as a result of the Company’s investments in available-for-sale securities, the Company’s comprehensive loss includes unrealized gains and unrealized losses on those available-for-sale securities. Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02 , Leases (Topic 842) Leases In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480), Derivatives and Hedging (Topic 815) I. Accounting for Certain Financial Instruments with Down Round Features II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception . In March 2020, the FASB issued (“ASU 2020-03”), Codification Improvements to Financial Instruments, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Topic 326 Topic 842 (Leases)

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value of Financial Assets and Liabilities	3. Fair Value of Financial Assets and Liabilities The following table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicates the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2020 Quoted Active for Assets Significant Observable Inputs Significant Observable Inputs Description Total (Level 1) (Level 2) (Level 3) Assets: Money market funds, included in cash and cash equivalents $ 42,047 $ 42,047 $ — $ — Marketable securities: United States Treasury Bills 21,989 21,989 — — Corporate debt securities 18,367 — 18,367 — Commercial paper 11,268 — 11,268 — Total financial assets $ 93,671 $ 64,036 $ 29,635 $ — December 31, 2019 Quoted Active for Assets Significant Observable Inputs Significant Observable Inputs Description Total (Level 1) (Level 2) (Level 3) Assets: Money market funds, included in cash and cash equivalents $ 4,477 $ 4,477 $ — $ — Marketable securities: Corporate debt securities 5,772 — 5,772 — Commercial paper 18,199 — 18,199 — Total financial assets $ 28,448 $ 4,477 $ 23,971 $ — As of June 30, 2020 and December 31, 2019, the Company’s Level 1 financial assets consisted of cash equivalents held in money market funds, which are valued using quoted market prices in active markets without any valuation adjustment, and United States treasury bills, which are based on quoted market prices in active markets. The financial assets valued based on Level 2 inputs consist of corporate debt securities and commercial paper, which consist of investments in highly-rated investment-grade securities. The Company estimates the fair values of these marketable securities by taking into consideration valuations obtained from third-party pricing sources. These pricing sources utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include market pricing based on real-time trade data for the same or similar securities, issuer credit spreads, benchmark yields, and other observable inputs. The Company validates the prices provided by its third-party pricing sources by understanding the models used, obtaining market values from other pricing sources and analyzing pricing data in certain instances. During the three and six months ended June 30, 2020 and the year ended December 31, 2019, there were no transfers between fair value measurement levels. The carrying values of other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities.

Investments

Investments	6 Months Ended
	Jun. 30, 2020
Investments Debt And Equity Securities [Abstract]
Investments	4. Investments As of June 30, 2020 and December 31, 2019, the Company had short-term investments consisting of United States treasury bills, corporate debt securities, and commercial paper, which are considered to be available-for-sale investments. These are included in short-term investments on the condensed consolidated balance sheets, even though the stated maturity date may be one year or more beyond the current balance sheet date, as the Company views those securities as available for use in current operations, if needed. The following table summarizes the Company’s investments (in thousands): June 30, 2020 Amortized Gross Gains Gross Loss Fair Current: United States Treasury Bills $ 21,989 $ 21,989 Corporate debt securities $ 18,319 $ 50 $ (2 ) $ 18,367 Commercial Paper 11,268 1 (1 ) 11,268 Total $ 51,576 $ 51 $ (3 ) $ 51,624 December 31, 2019 Amortized Gross Gains Gross Loss Fair Current: Commercial paper $ 18,167 $ 32 $ — $ 18,199 Corporate debt securities 5,772 — — 5,772 Total $ 23,939 $ 32 $ — $ 23,971 As of June 30, 2020, the Company had four available-for-sale securities with an aggregate value of approximately $14.5 million in immaterial unrealized loss positions for less than twelve months. As of December 31, 2019, the Company had no available-for-sale securities in unrealized loss positions The Company has the intent and ability to hold such securities until recovery. The Company determined that there was no material change in the credit risk of these investments

Accrued Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2020
Payables And Accruals [Abstract]
Accrued Expenses	5. Accrued Expenses Accrued expenses consisted of the following (in thousands): June 30, 2020 December 31, 2019 Accrued research and development expenses $ 1,357 $ 1,106 Accrued compensation and benefits 1,310 802 Accrued professional services 431 330 Accrued other 81 302 Total accrued expenses $ 3,179 $ 2,540

License Agreements

License Agreements	6 Months Ended
	Jun. 30, 2020
License Agreements [Abstract]
License Agreements	6. License Agreements Agreement with Lundbeck In April 2016, the Company entered into a license agreement with Lundbeck A/S (“Lundbeck” and the “Lundbeck Agreement”) pursuant to which Lundbeck granted the Company the following licenses within the field of prevention, treatment or diagnosis of hemoglobinopathy disorders and/or other diseases or disorders, including those directly or indirectly related to hemoglobinopathies: (1) an exclusive, royalty-bearing license to certain patent rights and certain know-how owned or otherwise controlled by Lundbeck (“Licensed Technology”) to research, develop, make, use, sell, and commercialize products (“Licensed Products”) from PDE9 inhibitors, which included IMR-687 (“Licensed Compounds”); (2) a non-exclusive license to the Licensed Technology to make, research, develop, and use such Licensed Technology to enable research and development, with certain restrictions; and (3) a sublicensing right that allows the Company to grant sublicenses to third parties to use the Licensed Technology subject to the certain terms detailed in the Lundbeck Agreement. Under the Lundbeck Agreement, the Company is subject to certain achievement dates for development milestones as defined in the agreement. The regulatory milestones due under the Lundbeck Agreement depend on the products being developed. Development milestones due under the Lundbeck Agreement with respect to the Licensed Compounds total up to $23.5 million, and, for any products that contain PDE9 inhibitors other than Licensed Compounds, total up to $11.8 million. The Company also agreed to pay tiered royalties based on net sales of all products licensed under the agreement in the low single-digit percentages. To date, pursuant to the license agreement, the Company has made cash payments to Lundbeck of $1.8 million consisting of an upfront payment and ongoing milestone payments, which were recorded as research and development expenses. No payments were made during the year ended December 31, 2019, or for the three and six months ended June 30, 2020. As partial consideration for the license, the Company issued 167,523 shares of common stock to Lundbeck, which represented 8.0% of the Company’s then outstanding equity pursuant to a restricted stock agreement. The shares were fully vested on the date of issuance. The Company also allowed Lundbeck to participate in the fourth tranche of its Series A preferred stock financing in November 2018 at $1.00 per share. The Lundbeck Agreement can be terminated by the Company at any time with 180 days’ written notice. The Company or Lundbeck may terminate the agreement by written notice within a specified period of time in the event of a material breach.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and Contingencies Lease Agreements In 2016, the Company entered into an agreement for office space located in Cambridge, Massachusetts, which was a month-to-month lease, with a related party (see Note 13). The agreement for this space terminated on August 17, 2019. The Company recorded rent expense of less than $0.1 million during the three and six months ended June 30, 2019. In May 2019, the Company entered into a new operating lease agreement for office space totaling 4,210 square feet, located in Boston, Massachusetts with a 62-month term. The lease includes a rent escalation clause which results in cash rental payments of approximately $0.3 million annually. Rent expense is being recognized on a straight-line basis over the lease term. In addition to the base rent, the Company is also responsible for its share of operating expenses, electricity and real estate taxes, in accordance with the terms of the Lease Agreement. The Company provided a security deposit of approximately $0.1 million in May 2019, which is included as a component of other assets on the Company’s unaudited condensed consolidated balance sheets as of June 30, 2020 and December 31, 2019. The Company occupied the space in August 2019 and commenced recognition of rent expense. The Company recorded rent expense of less than $0.1 million during the three months ended June 30, 2020, and approximately $0.1 million during the six months ended June 30, 2020. The following table summarizes the future minimum lease payments due under the Company’s operating lease (in thousands): June 30, 2020 2020 $ 135 2021 273 2022 278 2023 284 Thereafter 229 $ 1,199 Legal Proceedings The Company may from time to time be party to litigation arising in the ordinary course of business. The Company was not subject to any material legal proceedings during the three and six months ended June 30, 2020 and year ended December 31, 2019, and no material legal proceedings are currently pending or, to the best of its knowledge, threatened. Indemnification Obligations The Company agrees to standard indemnification obligations as part of entering into agreements in the ordinary course of business. Pursuant to the indemnification provisions, the Company agrees to indemnify, hold harmless, and to reimburse the indemnified party for losses suffered or incurred by the indemnified party, generally the Company’s business partners, in connection with matters specified in the applicable provision, which may include any U.S. patent or any copyright or other intellectual property infringement claim by any third-party with respect to the Company’s products or product liability claims by any third-party with respect to the Company’s products. The term of these indemnification obligations is generally perpetual any time after execution of the agreement. The potential amount of future payments the Company could be required to make under these indemnification obligations is unlimited. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification obligations.

Convertible Preferred Stock

Convertible Preferred Stock	6 Months Ended
	Jun. 30, 2020
Temporary Equity Disclosure [Abstract]
Convertible Preferred Stock	8. Convertible Preferred Stock On February 25, 2020, the Company raised $17.1 million in net proceeds from the sale of 1,562,994‬ shares of Series B Preferred Stock, at a price of $10.9722 per share, upon a waiver of specified milestone conditions from the holders of a majority of the shares then held by the holders of Series B Preferred Stock. Upon issuance, each share of Series B Preferred Stock included an embedded beneficial conversion feature as the estimated fair value of the Company’s common stock on the date of issuance of the Series B Preferred Stock was higher than the effective conversion price of the Series B Preferred Stock of $10.9722 per share. Given the proximity of the issuance to the Company’s public offering, the Company utilized the $16.00 public offing price of its common stock Upon the completion of the IPO on March 16, 2020, all 70,378,661 shares of outstanding preferred stock automatically converted into 11,172,955 shares of common stock. Prior to the conversion, the holders of the preferred stock were entitled to receive noncumulative dividends of 8% per annum of the Series B issuance price only when and if declared by the Company’s Board of Directors. No dividends have been declared by the Company’s Board of Directors since inception. As of December 31, 2019, preferred stock consisted of the following (in thousands, except share data): December 31, 2019 Preferred Stock Authorized Preferred Stock Issued and Outstanding Carrying Value Liquidation Value Common stock Issuable Upon Conversion Series Seed Preferred Stock 2,712,960 2,712,960 $ 1,460 $ 2,713 430,693 Series A Preferred Stock 31,499,040 31,499,040 30,729 31,499 5,000,623 Series B Preferred Stock 36,166,661 26,321,313 45,575 45,849 4,178,645 70,378,661 60,533,313 $ 77,764 $ 80,061 9,609,961

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2020
Equity [Abstract]
Stockholders' Equity	9. Stockholders’ Equity On August 13, 2019, the Company’s board of directors, and on February 26, 2020, the Company’s stockholders, approved the Company’s restated certificate of incorporation, which became effective upon closing of the IPO on March 16, 2020, to authorize Common stockholders are entitled to receive dividends, as may be declared by the Board, if any, subject to the preferential dividend rights of any preferred stock then outstanding. Through June 30, 2020, no cash dividends have been declared or paid. As of June 30, 2020, 10,000,000 shares of preferred stock were authorized and no shares of preferred stock were issued or outstanding. As of June 30, 2020 and December 31, 2019, the Company has reserved for future issuance the following shares of common stock: June 30, 2020 December 31, 2019 Conversion of outstanding preferred stock — 9,609,961 Shares reserved for future issuance under the 2016 Stock Incentive Plan — 228,852 Shares reserved for future issuance under the 2020 Equity Incentive Plan 1,321,261 — Shares reserved for future issuance under the 2020 Employee Stock Purchase Plan 193,216 — 1,514,477 9,838,813

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2020
Compensation Related Costs [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation 2016 Stock Incentive Plan The Company’s 2016 Stock Incentive Plan, (the “2016 Plan”) provided for the grant of restricted stock, restricted stock units, stock appreciation rights, incentive stock options, non-statutory stock options and other stock-based awards to employees, officers, members of the Board, consultants and advisors of the Company. As of December 31, 2019, the number of shares of common stock authorized to be issued under the 2016 Plan was 2,091,969, of which 228,852 shares remained available for future grants as of December 31, 2019. As of the effective date of the 2020 Equity Incentive Plan (the “2020 Plan”), no shares remained available for future issuance under the 2016 Plan. Any options or awards outstanding under the 2016 Plan remain outstanding and effective. 2020 Equity Incentive Plan On October 1, 2019, the Company’s board of directors adopted, and on February 26, 2020 the Company’s stockholders approved, the 2020 Equity Incentive Plan (the “2020 Plan”), which became effective on March 11, 2020. The 2020 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares reserved for issuance under the 2020 Plan is the sum of: (1) 1,220,283 shares of the Company’s common stock; plus (2) the number of shares (up to a maximum of 2,091,969 shares) equal to the sum of (x) 228,852 shares, which represents the Company’s common stock reserved for issuance under the 2016 Plan that remained available for grant under the 2016 Plan as of March 11, 2020 and (y) the number of shares of the Company’s common stock subject to outstanding awards granted under the 2016 Plan that expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right. The number of shares reserved shall be annually increased on the first day of each fiscal year, beginning with the fiscal year ending December 31, 2021 and continuing until, and including, the fiscal year ending December 31, 2030, equal to the lesser of (i) 4% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (ii) an amount determined by the Company’s board of directors. No more than 8,541,982 shares of common stock may be issued as incentive stock options under the 2020 Plan. The shares of common stock underlying any awards that expire, terminate, or are otherwise surrendered, cancelled, forfeited or repurchased by the Company under the 2016 Plan or the 2020 Plan will be added back to the shares of common stock available for issuance under the 2020 Plan As of June 30, 2020, there were 1,321,261 shares available for future issuance under the 2020 Plan. For financial reporting purposes, the Company performed common stock valuations with the assistance of a third-party specialist through October 23, 2019 to determine stock-based compensation expense for stock options. Upon completion of the IPO, the fair value of the common stock on the grant date was based on the closing price of the stock on the Nasdaq Global Select Market on the date of grant. The following table summarizes the Company’s stock option activity: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2019 1,863,117 $ 4.60 8.90 Granted 322,439 16.00 Exercised (44,271 ) 4.92 Forfeited (194,565 ) 6.68 Outstanding as of June 30, 2020 1,946,720 $ 6.27 7.82 $ 41,579 Options vested and exercisable as of June 30, 2020 691,244 $ 4.21 5.70 $ 16,192 The aggregate intrinsic value of options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the common stock as of the end of the period. The weighted-average grant date fair value of the Company’s stock options granted during the three and six months ended June 30, 2020 was $10.36 and $10.16, respectively. The weighted-average grant date fair value of the Company’s stock options granted during each of the three and six months ended June 30, 2019 was $3.42. The assumptions that the Company used to determine the grant date fair value of stock options granted to employees, non-employees and members of the Board during the three and six months ended June 30, 2020 and 2019 were as follows, presented on a weighted-average basis Stock-based compensation expense was allocated as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Expected term (in years) 6.20 6.11 6.12 6.11 Expected volatility 73.79 % 69.70 % 72.35 % 69.70 % Expected dividend yield 0.00 % 0.00 % 0.00 % 0.00 % Risk-free interest rate 0.44 % 2.19 % 0.66 % 2.19 % Performance-based awards The Company granted stock options to purchase an aggregate of 220,928 shares of common stock to certain employees, officers and consultants and advisors of the Company on May 16, 2019, June 5, 2019 and June 21, 2019, which contain performance-based vesting criteria. Vesting of these options was contingent on the closing of the second tranche of Series B Preferred Stock financing. Stock-based compensation expense associated with performance-based stock options is recognized if the performance conditions are considered probable of being achieved, using management’s best estimates. As a result of the performance condition being met on February 25, 2020, these options will vest as to 25% of the shares underlying each option on February 25, 2021 and as to the remainder of the shares in equal quarterly installments for three years thereafter. The Company recognized stock-based compensation expense of less than $0.1 million for these options during the three and six months ended June 30, 2020, respectively. Stock-Based Compensation Stock-based compensation expense included in the Company’s unaudited condensed consolidated statements of operations and comprehensive loss is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Research and development $ 185 $ 59 $ 340 $ 73 General and administrative 365 138 570 219 Total stock-based compensation expense $ 550 $ 197 $ 910 $ 292 As of June 30, 2020 and December 31, 2019, total unrecognized compensation cost related to the unvested stock-based awards was $5.6 million and $3.3 million, respectively, which is expected to be recognized over a weighted-average period of 3.03 and 3.17 years, respectively. 2020 Employee Stock Purchase Plan On October 1, 2019, the Company’s board of directors adopted, and on February 26, 2020, the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the “2020 ESPP”), which became effective on March 11, 2020. The 2020 ESPP initially provides participating employees with the opportunity to purchase up to an aggregate of 193,216 shares of the Company’s common stock. The number of shares of the Company’s common stock reserved for issuance under the 2020 ESPP will automatically increase on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2021 and continuing until, and including, the fiscal year commencing on January 1, 2031, in an amount equal to the lowest of (i) 386,432 shares of the Company’s common stock, (ii) 1% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (iii) an amount determined by the Company’s board of directors.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes Deferred tax assets and deferred tax liabilities are recognized based on temporary differences between the financial reporting and tax basis of assets and liabilities using statutory rates. A valuation allowance is recorded against deferred tax assets if it is more likely than not that some or all of the deferred tax assets will not be realized. Due to the uncertainty surrounding the realization of the favorable tax attributes in future tax returns, the Company has recorded a full valuation allowance against the Company’s otherwise recognizable net deferred tax assets. On March 27, 2020, the United States enacted the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”). The Cares Act includes provisions relating to refundable payroll tax credits, deferment of the employer portion of certain payroll taxes, net operating loss carryback periods, alternative minimum tax credit refunds, modifications to the net interest deduction limitations and technical corrections to tax depreciation methods for qualified improvement property. The CARES Act also established a Paycheck Protection Program whereby certain small businesses are eligible for a loan to fund payroll expenses, rent, and related costs. The Company considered the provisions under the CARES Act and elected not to take advantage of the provisions of CARES Act as the effect of such provisions was not expected to have a material impact on the Company’s results of operations, cash flows and consolidated financial statements.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	12. Net Loss Per Share Basic and diluted net loss per share is determined by dividing net loss attributable to common stockholders by the weighted-average common shares outstanding during the period. Net loss applicable to common stockholders for the six months ended June 30, 2020 did not equal net loss due to the accretion of the beneficial conversion feature of Series B Preferred Stock in the amount of $7.9 million. The beneficial conversion feature was initially recorded as a discount on the Series B Preferred Stock with a corresponding amount recorded to Additional Paid-in Capital. The discount on the Series B Preferred Stock was then immediately written off as a deemed dividend as the Series B Preferred Stock does not have a stated redemption date and is immediately convertible at the option of the holder. The Company has computed diluted net loss per common share after giving consideration to all potentially dilutive common shares, including convertible preferred stock and options to purchase common stock during the period determined using the if-converted method, except where the effect of including such securities would be antidilutive. Because the Company has reported net losses since inception, these potential common shares have been anti-dilutive and basic and diluted loss per share have been the same. The Company excluded the following potential common shares from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Series Seed Preferred Stock — 430,693 — 430,693 Series A Preferred Stock — 5,000,623 — 5,000,623 Series B Preferred Stock — 4,178,645 — 4,178,645 Options to purchase common stock 1,946,720 645,568 1,946,720 645,568

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2020
Related Party Transactions [Abstract]
Related Party Transactions	13. Related Party Transactions Lundbeck Lundbeckfond Invest A/S is one of the Company’s stockholders and participated in all tranches of the Series A preferred stock financing and both tranches of the Series B preferred stock financing. Prior to the conversion of the Company’s preferred stock, Lundbeckfond Invest A/S owned 5,470,492 shares of Series A Preferred Stock as of December 31, 2019, and 478,749 shares of Series Seed Preferred Stock as of December 31, 2019. Lundbeckfond Invest A/S owned 1,326,111 shares of Series B Preferred Stock as of December 31, 2019. All shares of preferred stock converted into shares of common stock upon closing of the IPO. Lundbeckfond Invest A/S also purchased 187,500 shares of common stock in the IPO. This reflects a 6.9% and a 9.3% ownership interest on a fully diluted basis as of June 30, 2020 and December 31, 2019, respectively. Mette Kirstine Agger, a member of our board of directors, is a Managing Partner at Lundbeckfonden Ventures, which is an affiliate of Lundbeckfond Invest A/S. Lundbeck, an affiliate of Lundbeckfond Invest A/S, is also one of the Company’s stockholders and participated in the fourth tranche of the Company’s Series A preferred stock financing. Prior to the conversion of the Company’s preferred stock, Lundbeck owned 499,069 shares of Series A Preferred Stock as of December 31, 2019, as well as 443,271 shares of common stock issued in conjunction with the Lundbeck Agreement (See Note 6). All shares of preferred stock converted into shares of common stock upon closing of the IPO. This reflects a 2.5% and a 4.2% ownership interest on a fully diluted basis as of June 30, 2020 and December 31, 2019, respectively. Lundbeck did not participate in the Series B Preferred Stock financing. To date, pursuant to the Lundbeck Agreement, the Company has made cash payments to Lundbeck of $1.8 million consisting of an upfront payment and ongoing milestone payments which are recorded as research and development expense. Cydan Development, Inc. In January 2016, the Company entered into a Business Services Agreement with Cydan Development, Inc., or Cydan, pursuant to which Cydan provided office space, personnel assistance, and other business services to the Company on an as-needed basis. At the time the agreement was signed, Cydan was considered a related party because Cydan was a holder of more than 5% of the Company’s capital stock and Dr. James McArthur was the Company’s founder, President and Chief Executive Officer, a member of the Company’s board of directors and a holder of more than 5% of the Company’s capital stock and the Chief Scientific Officer of Cydan. As of June 30, 2020, Cydan is no longer considered a related party. The Company paid Cydan less than $0.1 million during the three and six months ended June 30, 2019 related to the Business Services Agreement, all of which was recorded as research and development expense. The Company agreed with Cydan to terminate the Business Services Agreement and all related services rendered by Cydan to the Company effective as of August 17, 2019. Accordingly, there were no amounts due to Cydan as of June 30, 2020 and December 31, 2019.

Benefit Plans

Benefit Plans	6 Months Ended
	Jun. 30, 2020
Compensation And Retirement Disclosure [Abstract]
Benefit Plans	14. Benefit Plans The Company established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code effective as of January 2019. This plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Matching contributions to the plan may be made at the discretion of the Board. The Company has made no contributions to the plan to date.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2020
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and as amended by Accounting Standards Updates of the Financial Accounting Standards Board (“FASB”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted from this report, as is permitted by such rules and regulations. Accordingly, these financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2019 and notes thereto, included in the Company’s Registration Statement on Form S-1/A, filed with the Securities Exchange Commission (“SEC”) on March 10, 2020. The unaudited condensed consolidated interim financial statements have been prepared on the same basis as the audited financial statements. In the opinion of the Company’s management, the accompanying unaudited condensed consolidated interim financial statements contain all adjustments which are necessary to present fairly the Company’s financial position as of June 30, 2020, the results of its operations for the three and six months ended June 30, 2020 and 2019 and cash flows for the six months ended June 30, 2020 and 2019. Such adjustments are of a normal and recurring nature. The results for the three and six months ended June 30, 2020 are not necessarily indicative of the results for the year ending December 31, 2020, or for any future period.
Principles of Consolidation	Principles of Consolidation The accompanying unaudited condensed consolidated financial statements of the Company include the accounts of its wholly owned subsidiaries, IMARA Security Corporation and IMARA E.U. Limited. All intercompany transactions and balances have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these unaudited condensed consolidated financial statements include, but are not limited to, accrued research and development expenses, stock-based compensation expense, the fair value of the common stock and the intrinsic value of the beneficial conversation feature present in the second tranche of the Series B Preferred Stock issued in February of 2020. Actual results could differ materially from those estimates.
Segments	Segments Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one operating segment. The Company’s chief operating decision maker, its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purpose of allocating resources. All of the Company’s long-lived assets are held in the United States.
Deferred Offering Costs	Deferred Offering Costs The Company capitalizes certain legal, professional, accounting and other third-party fees that are directly associated with in-process equity issuances as deferred offering costs until such equity issuances are consummated. After consummation of the equity issuance, these costs are recorded as a reduction in the capitalized amount associated with the equity issuance. Should the equity issuance be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the unaudited condensed consolidated statement of operations and comprehensive loss.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity (deficit) that are excluded from net loss. The Company’s comprehensive loss was equal to net loss for the three and six months ended June 30, 2019. For the three and six month period ended June 30, 2020, as a result of the Company’s investments in available-for-sale securities, the Company’s comprehensive loss includes unrealized gains and unrealized losses on those available-for-sale securities.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02 , Leases (Topic 842) Leases In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480), Derivatives and Hedging (Topic 815) I. Accounting for Certain Financial Instruments with Down Round Features II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception . In March 2020, the FASB issued (“ASU 2020-03”), Codification Improvements to Financial Instruments, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Topic 326 Topic 842 (Leases)

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicates the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2020 Quoted Active for Assets Significant Observable Inputs Significant Observable Inputs Description Total (Level 1) (Level 2) (Level 3) Assets: Money market funds, included in cash and cash equivalents $ 42,047 $ 42,047 $ — $ — Marketable securities: United States Treasury Bills 21,989 21,989 — — Corporate debt securities 18,367 — 18,367 — Commercial paper 11,268 — 11,268 — Total financial assets $ 93,671 $ 64,036 $ 29,635 $ — December 31, 2019 Quoted Active for Assets Significant Observable Inputs Significant Observable Inputs Description Total (Level 1) (Level 2) (Level 3) Assets: Money market funds, included in cash and cash equivalents $ 4,477 $ 4,477 $ — $ — Marketable securities: Corporate debt securities 5,772 — 5,772 — Commercial paper 18,199 — 18,199 — Total financial assets $ 28,448 $ 4,477 $ 23,971 $ —

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2020
Investments Debt And Equity Securities [Abstract]
Summary of Investments	The following table summarizes the Company’s investments (in thousands): June 30, 2020 Amortized Gross Gains Gross Loss Fair Current: United States Treasury Bills $ 21,989 $ 21,989 Corporate debt securities $ 18,319 $ 50 $ (2 ) $ 18,367 Commercial Paper 11,268 1 (1 ) 11,268 Total $ 51,576 $ 51 $ (3 ) $ 51,624 December 31, 2019 Amortized Gross Gains Gross Loss Fair Current: Commercial paper $ 18,167 $ 32 $ — $ 18,199 Corporate debt securities 5,772 — — 5,772 Total $ 23,939 $ 32 $ — $ 23,971

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2020
Payables And Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consisted of the following (in thousands): June 30, 2020 December 31, 2019 Accrued research and development expenses $ 1,357 $ 1,106 Accrued compensation and benefits 1,310 802 Accrued professional services 431 330 Accrued other 81 302 Total accrued expenses $ 3,179 $ 2,540

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Summary of Future Minimum Lease Payments	The following table summarizes the future minimum lease payments due under the Company’s operating lease (in thousands): June 30, 2020 2020 $ 135 2021 273 2022 278 2023 284 Thereafter 229 $ 1,199

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	6 Months Ended
	Jun. 30, 2020
Temporary Equity Disclosure [Abstract]
Schedule of Preferred Stock	As of December 31, 2019, preferred stock consisted of the following (in thousands, except share data): December 31, 2019 Preferred Stock Authorized Preferred Stock Issued and Outstanding Carrying Value Liquidation Value Common stock Issuable Upon Conversion Series Seed Preferred Stock 2,712,960 2,712,960 $ 1,460 $ 2,713 430,693 Series A Preferred Stock 31,499,040 31,499,040 30,729 31,499 5,000,623 Series B Preferred Stock 36,166,661 26,321,313 45,575 45,849 4,178,645 70,378,661 60,533,313 $ 77,764 $ 80,061 9,609,961

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2020
Equity [Abstract]
Schedule of Shares Reserved for Future Issuance	As of June 30, 2020 and December 31, 2019, the Company has reserved for future issuance the following shares of common stock: June 30, 2020 December 31, 2019 Conversion of outstanding preferred stock — 9,609,961 Shares reserved for future issuance under the 2016 Stock Incentive Plan — 228,852 Shares reserved for future issuance under the 2020 Equity Incentive Plan 1,321,261 — Shares reserved for future issuance under the 2020 Employee Stock Purchase Plan 193,216 — 1,514,477 9,838,813

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2020
Compensation Related Costs [Abstract]
Summary of Stock Option Activity	The following table summarizes the Company’s stock option activity: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2019 1,863,117 $ 4.60 8.90 Granted 322,439 16.00 Exercised (44,271 ) 4.92 Forfeited (194,565 ) 6.68 Outstanding as of June 30, 2020 1,946,720 $ 6.27 7.82 $ 41,579 Options vested and exercisable as of June 30, 2020 691,244 $ 4.21 5.70 $ 16,192
Summary of Stock-Based Compensation Fair Value Assumptions	The assumptions that the Company used to determine the grant date fair value of stock options granted to employees, non-employees and members of the Board during the three and six months ended June 30, 2020 and 2019 were as follows, presented on a weighted-average basis Stock-based compensation expense was allocated as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Expected term (in years) 6.20 6.11 6.12 6.11 Expected volatility 73.79 % 69.70 % 72.35 % 69.70 % Expected dividend yield 0.00 % 0.00 % 0.00 % 0.00 % Risk-free interest rate 0.44 % 2.19 % 0.66 % 2.19 %
Summary of Stock-Based Compensation Expense	Stock-based compensation expense included in the Company’s unaudited condensed consolidated statements of operations and comprehensive loss is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Research and development $ 185 $ 59 $ 340 $ 73 General and administrative 365 138 570 219 Total stock-based compensation expense $ 550 $ 197 $ 910 $ 292

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Anti Dilutive Potential Common Shares Excluded From Computation of Diluted Net Loss Per Share	The Company excluded the following potential common shares from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Series Seed Preferred Stock — 430,693 — 430,693 Series A Preferred Stock — 5,000,623 — 5,000,623 Series B Preferred Stock — 4,178,645 — 4,178,645 Options to purchase common stock 1,946,720 645,568 1,946,720 645,568

Nature of the Business - Additi

Nature of the Business - Additional Information (Details) $ / shares in Units, $ in Thousands	Apr. 13, 2020USD ($)shares	Mar. 16, 2020USD ($)$ / sharesshares	Feb. 25, 2020USD ($)$ / sharesshares	Feb. 29, 2020	Jun. 30, 2020USD ($)shares	Jun. 30, 2019USD ($)	Dec. 31, 2019USD ($)shares
Nature Of Business [Line Items]
Reverse stock split					1-for-6.299
Reverse stock splits, conversion ratio				0.159
Convertible preferred stock, shares issued | shares					0		60,533,313
Proceeds from issuance of Series B convertible preferred stock, net of issuance costs					$ 17,150	$ 45,575
Gross proceeds from initial public offering		$ 75,200			80,427
Aggregate gross proceeds of common stock issued and sold	$ 11,300
Underwriting discounts and commissions and offering expenses					10,000
Conversion of outstanding preferred stock | shares		70,378,661
Common stock issued upon conversion | shares		11,172,955					9,609,961
Cash, cash equivalents, and investments					106,300
Accumulated deficit					72,172		$ 54,753
IPO
Nature Of Business [Line Items]
Preferred stock, per share | $ / shares		$ 16
Common stock issued and sold | shares	705,000	4,700,000
Net proceeds after deducting underwriting discounts and commissions and offering expenses					$ 76,500
Conversion of outstanding preferred stock | shares		70,378,661
Series B Preferred Stock
Nature Of Business [Line Items]
Convertible preferred stock, shares issued | shares							26,321,313
Common stock issued upon conversion | shares							4,178,645
Series B Preferred Stock | Second Tranche
Nature Of Business [Line Items]
Convertible preferred stock, shares issued | shares			1,562,994
Preferred stock, per share | $ / shares			$ 10.9722
Proceeds from issuance of Series B convertible preferred stock, net of issuance costs			$ 17,100
Series B Preferred Stock | Second Tranche | Maximum
Nature Of Business [Line Items]
Stock issuance costs			$ 100

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details)	6 Months Ended
	Jun. 30, 2020Segment
Accounting Policies [Abstract]
Number of operating segments	1

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets:
Marketable securities	$ 51,624	$ 23,971
Fair Value Measurements Recurring
Assets:
Total financial assets	93,671	28,448
Fair Value Measurements Recurring | Money Market Funds
Assets:
Cash and cash equivalents	42,047	4,477
Fair Value Measurements Recurring | United States Treasury Bills
Assets:
Marketable securities	21,989
Fair Value Measurements Recurring | Corporate Debt Securities
Assets:
Marketable securities	18,367	5,772
Fair Value Measurements Recurring | Commercial Paper
Assets:
Marketable securities	11,268	18,199
Fair Value Measurements Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Total financial assets	64,036	4,477
Fair Value Measurements Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Money Market Funds
Assets:
Cash and cash equivalents	42,047	4,477
Fair Value Measurements Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | United States Treasury Bills
Assets:
Marketable securities	21,989
Fair Value Measurements Recurring | Significant Other Observable Inputs (Level 2)
Assets:
Total financial assets	29,635	23,971
Fair Value Measurements Recurring | Significant Other Observable Inputs (Level 2) | Corporate Debt Securities
Assets:
Marketable securities	18,367	5,772
Fair Value Measurements Recurring | Significant Other Observable Inputs (Level 2) | Commercial Paper
Assets:
Marketable securities	$ 11,268	$ 18,199

Fair Value of Financial Asset_4

Fair Value of Financial Assets and Liabilities - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value, assets, Level 1 to Level 2 transfers, amount	$ 0	$ 0	$ 0
Fair value, assets, Level 2 to Level 1 transfers, amount	0	0	0
Fair value, asset transfers Into Level 3	0	0	0
Fair value, asset, transfers out of Level 3	$ 0	$ 0	$ 0

Investments - Summary of Invest

Investments - Summary of Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 51,576	$ 23,939
Gross Unrealized Gains	51	32
Gross Unrealized Loss	(3)
Short-term investments	51,624	23,971
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	11,268	18,167
Gross Unrealized Gains	1	32
Gross Unrealized Loss	(1)
Short-term investments	11,268	18,199
United States Treasury Bills
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	21,989
Short-term investments	21,989
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	18,319	5,772
Gross Unrealized Gains	50
Gross Unrealized Loss	(2)
Short-term investments	$ 18,367	$ 5,772

Investments - Additional Inform

Investments - Additional Information (Details)	Jun. 30, 2020USD ($)Position	Dec. 31, 2019USD ($)
Investments Debt And Equity Securities [Abstract]
Number of available-for-sale securities in unrealized loss positions for less than twelve months | Position	4
Available-for-sale securities in unrealized loss positions for less than twelve months	$ 14,500,000
Available-for-sale securities in unrealized loss positions		$ 0

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Accrued research and development expenses	$ 1,357	$ 1,106
Accrued compensation and benefits	1,310	802
Accrued professional services	431	330
Accrued other	81	302
Total accrued expenses	$ 3,179	$ 2,540

License Agreements - Additional

License Agreements - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended	51 Months Ended
	Apr. 30, 2016	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2020	Nov. 30, 2018
License Agreements [Line Items]
Common stock, shares issued		17,324,736	17,324,736	702,510	17,324,736
Lundbeck Agreement | Lundbeck
License Agreements [Line Items]
Maximum development milestones payments due	$ 23,500,000
Maximum development milestones payments due for other than licensed product	$ 11,800,000
Upfront and ongoing milestone payments		$ 0	$ 0	$ 0
Common stock, shares issued	167,523			443,271
Outstanding equity percentage pursuant to restricted stock agreement	8.00%
Notice period for agreement termination			180 days
Lundbeck Agreement | Lundbeck | Series A Preferred Stock | Fourth Tranche
License Agreements [Line Items]
Public offering price per share						$ 1
Lundbeck Agreement | Lundbeck | Research and Development Expense
License Agreements [Line Items]
Upfront and ongoing milestone payments					$ 1,800,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Commitments and Contingencies [Line Items]
Lease agreements office space termination date				Aug. 17, 2019
Rent expense				$ 100,000
Operating lease description				In May 2019, the Company entered into a new operating lease agreement for office space totaling 4,210 square feet, located in Boston, Massachusetts with a 62-month term.
Operating lease term of contract	62 months
Operating lease, payments	$ 300,000
Security deposit	$ 100,000
Maximum
Commitments and Contingencies [Line Items]
Rent expense		$ 100,000	$ 100,000		$ 100,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Future Minimum Lease Payments (Details) $ in Thousands	Jun. 30, 2020USD ($)
Lessee Disclosure [Abstract]
2020	$ 135
2021	273
2022	278
2023	284
Thereafter	229
Total	$ 1,199

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Details) - USD ($)	Mar. 16, 2020	Feb. 25, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Temporary Equity [Line Items]
Net proceeds from sale			$ 17,150,000	$ 45,575,000
Preferred shares, issued			0		60,533,313
Conversion of outstanding preferred stock	70,378,661
Common stock issued upon conversion	11,172,955				9,609,961
Dividends			$ 0
IPO
Temporary Equity [Line Items]
Stock value, per share	$ 16
Conversion of outstanding preferred stock	70,378,661
IPO | Common Stock
Temporary Equity [Line Items]
Stock value, per share	$ 16
Common stock issued upon conversion	11,172,955
Series B Preferred Stock
Temporary Equity [Line Items]
Preferred shares, issued					26,321,313
Common stock issued upon conversion					4,178,645
Noncumulative dividends percentage	8.00%
Series B Preferred Stock | Second Tranche
Temporary Equity [Line Items]
Net proceeds from sale		$ 17,100,000
Preferred shares, issued		1,562,994
Stock value, per share		$ 10.9722
Intrinsic value of beneficial conversion discount		$ 7,900,000

Convertible Preferred Stock - S

Convertible Preferred Stock - Schedule of Preferred Stock (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 16, 2020	Dec. 31, 2019
Temporary Equity [Line Items]
Preferred Stock Authorized	0		70,378,661
Preferred Stock Issued	0		60,533,313
Preferred Stock Outstanding	0		60,533,313
Carrying Value			$ 77,764
Liquidation Value			$ 80,061
Common stock issued upon conversion		11,172,955	9,609,961
Series Seed Preferred Stock
Temporary Equity [Line Items]
Preferred Stock Authorized			2,712,960
Preferred Stock Issued			2,712,960
Preferred Stock Outstanding			2,712,960
Carrying Value			$ 1,460
Liquidation Value			$ 2,713
Common stock issued upon conversion			430,693
Series A Preferred Stock
Temporary Equity [Line Items]
Preferred Stock Authorized			31,499,040
Preferred Stock Issued			31,499,040
Preferred Stock Outstanding			31,499,040
Carrying Value			$ 30,729
Liquidation Value			$ 31,499
Common stock issued upon conversion			5,000,623
Series B Preferred Stock
Temporary Equity [Line Items]
Preferred Stock Authorized			36,166,661
Preferred Stock Issued			26,321,313
Preferred Stock Outstanding			26,321,313
Carrying Value			$ 45,575
Liquidation Value			$ 45,849
Common stock issued upon conversion			4,178,645

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Mar. 16, 2020	Dec. 31, 2019
Equity [Abstract]
Preferred stock, shares authorized	10,000,000	10,000,000	0
Preferred stock, par value	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000	100,000,000
Common stock, par value	$ 0.001	$ 0.001	$ 0.001
Cash dividends	$ 0
Preferred stock, shares issued	0		0
Preferred stock, shares outstanding	0		0

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Shares Reserved for Future Issuance (Details) - shares	Jun. 30, 2020	Mar. 11, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Shares reserved for future issuance	1,514,477		9,838,813
Conversion of Outstanding Preferred Stock
Class Of Stock [Line Items]
Shares reserved for future issuance			9,609,961
2016 Stock Incentive Plan
Class Of Stock [Line Items]
Shares reserved for future issuance	0	228,852	228,852
2020 Equity Incentive Plan
Class Of Stock [Line Items]
Shares reserved for future issuance	1,321,261
2020 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Shares reserved for future issuance	193,216	193,216

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 11, 2020	Jun. 21, 2019	Jun. 05, 2019	May 16, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future issuance					1,514,477		1,514,477		9,838,813
Share-based compensation award, granted							322,439
Share-based compensation award, weighted-average fair value					$ 10.36	$ 3.42	$ 10.16	$ 3.42
Stock-based compensation expense					$ 550	$ 197	$ 910	$ 292
Unrecognized stock-based compensation expense					5,600		$ 5,600		$ 3,300
Expected weighted average period to recognize expense							3 years 10 days		3 years 2 months 1 day
Performance Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation award, granted		220,928	220,928	220,928
Performance Based Awards | Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vest percentage							25.00%
Maximum | Performance Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense					$ 100		$ 100
2016 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized									2,091,969
Shares remaining available for future issuance	228,852				0		0		228,852
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future issuance					1,321,261		1,321,261
Number of shares of common stock that may be issued accordance with plan	1,220,283
Description of changes in the number of shares reserved for issuance							The number of shares reserved shall be annually increased on the first day of each fiscal year, beginning with the fiscal year ending December 31, 2021 and continuing until, and including, the fiscal year ending December 31, 2030, equal to the lesser of (i) 4% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (ii) an amount determined by the Company’s board of directors.
Common stock outstanding percent	4.00%
2020 Equity Incentive Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized	2,091,969
Number of shares of common stock that may be issued accordance with plan	8,541,982
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future issuance	193,216				193,216		193,216
Number of shares of common stock that may be issued accordance with plan	386,432
Common stock outstanding percent	1.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020USD ($)$ / sharesshares	Dec. 31, 2019$ / sharesshares
Compensation Related Costs [Abstract]
Number of Shares, Beginning Balance | shares	1,863,117
Number of Shares, Granted | shares	322,439
Number of Shares, Exercised | shares	(44,271)
Number of Shares, Forfeited | shares	(194,565)
Number of Shares, Ending Balance | shares	1,946,720	1,863,117
Number of Shares, Options vested and exercisable | shares	691,244
Weighted-Average Exercise Price, Beginning Balance | $ / shares	$ 4.60
Weighted-Average Exercise Price, Granted | $ / shares	16
Weighted-Average Exercise Price, Exercised | $ / shares	4.92
Weighted-Average Exercise Price, Forfeited | $ / shares	6.68
Weighted-Average Exercise Price, Ending Balance | $ / shares	6.27	$ 4.60
Weighted-Average Exercise Price, Options vested and exercisable | $ / shares	$ 4.21
Weighted-Average Remaining Contractual Term, Outstanding	7 years 9 months 25 days	8 years 10 months 24 days
Weighted-Average Remaining Contractual Term, Options vested and exercisable	5 years 8 months 12 days
Aggregate Intrinsic Value, Balance | $	$ 41,579
Aggregate Intrinsic Value, Options vested and exercisable | $	$ 16,192

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock-Based Compensation Fair Value Assumptions (Details) - Stock Options	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 2 months 12 days	6 years 1 month 9 days	6 years 1 month 13 days	6 years 1 month 9 days
Expected volatility	73.79%	69.70%	72.35%	69.70%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	0.44%	2.19%	0.66%	2.19%

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 550	$ 197	$ 910	$ 292
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	185	59	340	73
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 365	$ 138	$ 570	$ 219

Net Loss Per Share - Additional

Net Loss Per Share - Additional Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020USD ($)
Earnings Per Share [Abstract]
Accretion of Series B convertible preferred stock	$ 7,858

Net Loss Per Share - Anti Dilut

Net Loss Per Share - Anti Dilutive Potential Common Shares Excluded From Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per common share	1,946,720	645,568	1,946,720	645,568
Series Seed Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per common share		430,693		430,693
Series A Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per common share		5,000,623		5,000,623
Series B Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted net loss per common share		4,178,645		4,178,645

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - USD ($)	Apr. 13, 2020	Mar. 16, 2020	Jan. 31, 2016	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Jun. 30, 2020	Apr. 30, 2016
Related Party Transaction [Line Items]
Shares owned				0			0		60,533,313	0
Common stock, shares issued				17,324,736			17,324,736		702,510	17,324,736
Common Stock
Related Party Transaction [Line Items]
Number of common stock purchased				705,000	4,700,000
IPO
Related Party Transaction [Line Items]
Number of common stock purchased	705,000	4,700,000
Lundbeckfond Invest A/S
Related Party Transaction [Line Items]
Ownership interest percentage				6.90%			6.90%		9.30%	6.90%
Lundbeckfond Invest A/S | IPO | Common Stock
Related Party Transaction [Line Items]
Number of common stock purchased		187,500
Lundbeck | Lundbeck Agreement
Related Party Transaction [Line Items]
Common stock, shares issued									443,271		167,523
Ownership interest percentage				2.50%			2.50%		4.20%	2.50%
Upfront and ongoing milestone payments				$ 0			$ 0		$ 0
Lundbeck | Lundbeck Agreement | Research and Development Expense
Related Party Transaction [Line Items]
Upfront and ongoing milestone payments										$ 1,800,000
Cydan Development Incorporation
Related Party Transaction [Line Items]
Due to related party				$ 0			$ 0		$ 0	$ 0
Cydan Development Incorporation | Business Services Agreement
Related Party Transaction [Line Items]
Related party, minimum percentage of capital stock owned			5.00%
Cydan Development Incorporation | Business Services Agreement | Research and Development Expense
Related Party Transaction [Line Items]
Payments to related party on related services						$ 100,000		$ 100,000
Series A Preferred Stock
Related Party Transaction [Line Items]
Shares owned									31,499,040
Series A Preferred Stock | Lundbeckfond Invest A/S
Related Party Transaction [Line Items]
Shares owned									5,470,492
Series A Preferred Stock | Lundbeck | Lundbeck Agreement
Related Party Transaction [Line Items]
Shares owned									499,069
Series Seed Preferred Stock
Related Party Transaction [Line Items]
Shares owned									2,712,960
Series Seed Preferred Stock | Lundbeckfond Invest A/S
Related Party Transaction [Line Items]
Shares owned									478,749
Series B Preferred Stock
Related Party Transaction [Line Items]
Shares owned									26,321,313
Series B Preferred Stock | Lundbeckfond Invest A/S
Related Party Transaction [Line Items]
Shares owned									1,326,111