Stoke Therapeutics (STOK) 10-Q 7 Nov 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Oct. 30, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity File Number	001-38938
Entity Registrant Name	Stoke Therapeutics, Inc.
Entity Central Index Key	0001623526
Entity Tax Identification Number	47-1144582
Entity Address, Address Line One	45 Wiggins Ave
Entity Address City Or Town	Bedford
Entity Address State Or Province	MA
Entity Address Postal Zip Code	01730
City Area Code	781
Local Phone Number	430-8200
Trading Symbol	STOK
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		44,653,782
Entity Incorporation State Country Code	DE
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false

Consolidated balance sheets

Consolidated balance sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 189,977	$ 113,556
Marketable securities	24,741	116,039
Prepaid expenses	10,936	10,932
Other current assets	4,269	2,955
Interest receivable	96	588
Total current assets	230,019	244,070
Restricted cash	569	569
Operating lease right-of-use assets	3,084	4,753
Property and equipment, net	6,217	6,675
Total assets	239,889	256,067
Current liabilities:
Accounts payable	3,076	766
Accrued and other current liabilities	13,390	15,748
Deferred revenue - current portion	8,735	14,880
Total current liabilities	25,201	31,394
Deferred revenue - net of current portion	40,730	36,856
Other long term liabilities	959	2,968
Total long term liabilities	41,689	39,824
Total liabilities	66,890	71,218
Commitments and contingencies (Note 6)
Stockholders’ equity
Common stock, par value of $0.0001 per share; 300,000,000 shares authorized, 44,293,115 and 39,439,575 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	4	4
Additional paid-in capital	548,033	483,170
Accumulated other comprehensive loss	(147)	(1,175)
Accumulated deficit	(374,891)	(297,150)
Total stockholders’ equity	172,999	184,849
Total liabilities and stockholders’ equity	$ 239,889	$ 256,067

Consolidated balance sheets (Pa

Consolidated balance sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	44,293,115	39,439,575
Common stock, shares outstanding	44,293,115	39,439,575

Consolidated statements of oper

Consolidated statements of operations and comprehensive loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue	$ 3,308	$ 2,905	$ 5,978	$ 9,137
Operating expenses:
Research and development	20,271	20,109	60,453	56,777
General and administrative	10,271	9,944	30,712	29,540
Total operating expenses	30,542	30,053	91,165	86,317
Loss from operations	(27,234)	(27,148)	(85,187)	(77,180)
Other income:
Interest income (expense), net	2,651	995	7,321	1,643
Other income (expense), net	41	42	125	125
Total other income	2,692	1,037	7,446	1,768
Net loss	$ (24,542)	$ (26,111)	$ (77,741)	$ (75,412)
Net loss per share, basic	$ (0.55)	$ (0.66)	$ (1.78)	$ (1.95)
Net loss per share, diluted	$ (0.55)	$ (0.66)	$ (1.78)	$ (1.95)
Weighted-average common shares outstanding, basic	44,266,017	39,420,310	43,669,987	38,716,615
Weighted-average common shares outstanding, diluted	44,266,017	39,420,310	43,669,987	38,716,615
Comprehensive loss:
Net loss	$ (24,542)	$ (26,111)	$ (77,741)	$ (75,412)
Other comprehensive gain (loss):
Unrealized gain (loss) on marketable securities	232	(427)	1,028	(1,535)
Total other comprehensive loss	232	(427)	1,028	(1,535)
Comprehensive loss	$ (24,310)	$ (26,538)	$ (76,713)	$ (76,947)

Consolidated statements of stoc

Consolidated statements of stockholders' equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at Dec. 31, 2021	$ 217,777	$ 4	$ 414,024	$ (168)	$ (196,083)
Balance, Shares at Dec. 31, 2021		36,902,499
Net loss	(24,649)				(24,649)
Unrealized gain (loss) on marketable securities	(516)			(516)
Stock-based compensation	4,975		4,975
Issuance of common stock upon exercise of stock options	93		93
Issuance of common stock upon exercise of stock options, Shares		53,377
Shares sold as part of controlled equity offering sales agreement	42,128		42,128
Shares sold as part of controlled equity offering sales agreement, Shares		2,080,486
Issuance of common stock related to employee stock purchase plan	169		169
Issuance of common stock related to employee stock purchase plan, Shares		8,307
Balance at Mar. 31, 2022	239,977	$ 4	461,389	(684)	(220,732)
Balance, Shares at Mar. 31, 2022		39,044,669
Balance at Dec. 31, 2021	217,777	$ 4	414,024	(168)	(196,083)
Balance, Shares at Dec. 31, 2021		36,902,499
Net loss	(75,412)
Unrealized gain (loss) on marketable securities	(1,535)
Balance at Sep. 30, 2022	204,143	$ 4	477,337	(1,703)	(271,495)
Balance, Shares at Sep. 30, 2022		39,426,440
Balance at Mar. 31, 2022	239,977	$ 4	461,389	(684)	(220,732)
Balance, Shares at Mar. 31, 2022		39,044,669
Net loss	(24,652)				(24,652)
Unrealized gain (loss) on marketable securities	(592)			(592)
Stock-based compensation	6,163		6,163
Issuance of common stock upon exercise of stock options	326		326
Issuance of common stock upon exercise of stock options, Shares		194,498
Shares sold as part of controlled equity offering sales agreement	3,099		3,099
Shares sold as part of controlled equity offering sales agreement, Shares		143,300
Balance at Jun. 30, 2022	224,321	$ 4	470,977	(1,276)	(245,384)
Balance, Shares at Jun. 30, 2022		39,382,467
Net loss	(26,111)				(26,111)
Unrealized gain (loss) on marketable securities	(427)			(427)
Stock-based compensation	5,926		5,926
Issuance of common stock upon exercise of stock options	33		33
Issuance of common stock upon exercise of stock options, Shares		8,278
Shares sold as part of controlled equity offering sales agreement, Shares		35,695
Issuance of common stock related to employee stock purchase plan	401		401
Balance at Sep. 30, 2022	204,143	$ 4	477,337	(1,703)	(271,495)
Balance, Shares at Sep. 30, 2022		39,426,440
Balance at Dec. 31, 2022	184,849	$ 4	483,170	(1,175)	(297,150)
Balance, Shares at Dec. 31, 2022		39,439,575
Net loss	(22,545)				(22,545)
Unrealized gain (loss) on marketable securities	577			577
Stock-based compensation	5,887		5,887
Issuance of common stock upon exercise of stock options	158		158
Issuance of common stock upon exercise of stock options, Shares		80,611
Shares sold as part of controlled equity offering sales agreement	44,743		44,743
Shares sold as part of controlled equity offering sales agreement, Shares		4,635,353
Issuance of common stock related to employee stock purchase plan	153		153
Issuance of common stock related to employee stock purchase plan, Shares		19,550
Balance at Mar. 31, 2023	213,822	$ 4	534,111	(598)	(319,695)
Balance, Shares at Mar. 31, 2023		44,175,089
Balance at Dec. 31, 2022	184,849	$ 4	483,170	(1,175)	(297,150)
Balance, Shares at Dec. 31, 2022		39,439,575
Net loss	(77,741)
Unrealized gain (loss) on marketable securities	1,028
Balance at Sep. 30, 2023	172,999	$ 4	548,033	(147)	(374,891)
Balance, Shares at Sep. 30, 2023		44,293,115
Balance at Mar. 31, 2023	213,822	$ 4	534,111	(598)	(319,695)
Balance, Shares at Mar. 31, 2023		44,175,089
Net loss	(30,654)				(30,654)
Unrealized gain (loss) on marketable securities	219			219
Stock-based compensation	6,760		6,760
Issuance of common stock upon exercise of stock options	48		48
Issuance of common stock upon exercise of stock options, Shares		27,908
Balance at Jun. 30, 2023	190,195	$ 4	540,919	(379)	(350,349)
Balance, Shares at Jun. 30, 2023		44,202,997
Net loss	(24,542)				(24,542)
Unrealized gain (loss) on marketable securities	232			232
Stock-based compensation	6,552		6,552
Issuance of common stock upon exercise of stock options	161		161
Issuance of common stock upon exercise of stock options, Shares		38,197
Issuance of common stock related to employee stock purchase plan	401		401
Issuance of common stock related to employee stock purchase plan, Shares		51,921
Balance at Sep. 30, 2023	$ 172,999	$ 4	$ 548,033	$ (147)	$ (374,891)
Balance, Shares at Sep. 30, 2023		44,293,115

Consolidated statements of cash

Consolidated statements of cash flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (77,741)	$ (75,412)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,845	937
Amortization and accretion of marketable securities	(236)	(60)
Stock-based compensation	19,199	17,064
Loss on disposal of property and equipment	1
Reduction in the carrying amount of right of use assets	1,669	1,446
Changes in assets and liabilities:
Prepaid expenses and other current assets	(824)	(3,655)
Accounts payable and accrued liabilities	(2,059)	(3,729)
Deferred revenue	(2,272)	53,916
Net cash used in operating activities	(60,418)	(9,493)
Cash flows from investing activities:
Purchases of marketable securities		(206,190)
Purchases of property and equipment	(1,387)	(3,553)
Sales of marketable securities	92,562	141,371
Net cash provided by (used in) investing activities	91,175	(68,372)
Cash flows from financing activities:
Proceeds from Employee Stock Purchase Plan	554	570
Proceeds from issuance of common stock upon exercise of stock options	367	452
Proceeds from controlled equity offering sales agreement	44,743	45,344
Net cash provided by financing activities	45,664	46,366
Net decrease in cash, cash equivalents and restricted cash	76,421	(31,499)
Cash, cash equivalents and restricted cash—beginning of period	114,125	145,464
Cash, cash equivalents and restricted cash—end of period	$ 190,546	113,965
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets recognized in exchange for operating leases		1,802
Property and equipment included in accrued expense and accounts payable		$ 406

Nature of the Business

Nature of the Business	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Nature of the business	1. Nature of the business Organization Stoke Therapeutics, Inc. (the “Company”) was founded in June 2014 and was incorporated under the laws of the State of Delaware . The Company is a biotechnology company dedicated to addressing the underlying cause of severe diseases by upregulating protein expression with RNA-based medicines. Shelf Registration In May 2022, the Company filed a universal Shelf Registration statement on Form S-3 (the “Registration Statement”) with the SEC. The Registration Statement was declared effective by the SEC on May 31, 2022, and contains two prospectuses: a base prospectus, which covers the offering, issuance and sale by the Company of up to a maximum aggregate offering price of $ 400,000,000 of its common stock, preferred stock, debt securities, warrants to purchase common stock, preferred stock or debt securities, subscription rights to purchase common stock, preferred stock or debt securities and/or units consisting of some or all of these securities; and a sales agreement prospectus covering the offering, issuance and sale by the Company of up to a maximum aggregate offering price of $ 150,000,000 of its common stock that may be issued and sold under a Controlled Equity Offering Sales Agreement (“Sales Agreement”). The specific terms of any securities to be offered pursuant to the base prospectus will be specified in a prospectus supplement to the base prospectus. The $ 150,000,000 of common stock that may be offered, issued and sold under the sales agreement prospectus is included in the $ 400,000,000 of securities that may be offered, issued and sold by the Company under the base prospectus. As of September 30, 2023 , the Company had issued approximately 4.6 million shares of common stock pursuant to the Sales Agreement for net proceeds of $ 44.7 million. We may terminate this at-the-market program at any time, pursuant to its terms. Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive 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 significant revenue from product sales. Liquidity The Company expects that its operating losses and negative cash flows will continue for the foreseeable future. As of the issuance date of these unaudited consolidated financial statements, the Company expects that its cash, cash equivalents and marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements through at least twelve months from the issuance date of these unaudited consolidated financial statements.

Summary of Significant Accounti

Summary of Significant Accounting Policies and Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of significant accounting policies and recent accounting pronouncements	2. Summary of significant accounting policies and recent accounting pronouncements Basis of presentation and consolidation The accompanying unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and include the accounts of the Company and its wholly-owned subsidiary. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). All intercompany transactions between and among its consolidated subsidiary have been eliminated. Unaudited interim financial information The accompanying interim unaudited consolidated financial statements and related disclosures are unaudited and have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Company’s consolidated financial statements and related notes as of and for the year ended December 31, 2022, which was filed with the SEC on March 6, 2023. The Company’s financial information as of September 30, 2023 and for the three and nine months ended September 30, 2023 and 2022 is unaudited, but in the opinion of management, all adjustments, consisting only of normal recurring adjustments, considered necessary for a fair presentation of the financial position, results of operations and cash flows at the dates and for the periods presented of the results of these interim periods have been included. The balance sheet information as of December 31, 2022 was derived from audited consolidated financial statements. The results of the Company’s operations for any interim period are not necessarily indicative of the results that may be expected for any other interim period or for a full fiscal year. Use of estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, equity, revenue, expenses and disclosure of contingent assets and liabilities. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from those estimates. Cash, cash equivalents and restricted cash The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. The Company deposits its cash in checking, sweep and money market accounts. At September 30, 2023, restricted cash consisted of money market accounts collateralizing letters of credit issued as security deposits in connection with the Company’s leases of its corporate facilities. Cash and cash equivalents, and restricted cash in the consolidated statements of cash flows consists of the following (in thousands): As of September 30, 2023 2022 Cash and cash equivalents $ 189,977 $ 113,396 Restricted cash - long-term 569 569 Total cash, cash equivalents and restricted cash $ 190,546 $ 113,965 Emerging growth company and smaller reporting company status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, the Company’s unaudited consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. The Company will remain an emerging growth company until the earliest of (1) the last day of its first fiscal year (a) in which the Company has total annual gross revenues of at least $1.235 billion, or (b) in which the Company is deemed to be a large accelerated filer, which means the market value of its common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30 th , (2) the date on which it has issued more than $1.0 billion in non-convertible debt securities during the prior three-year period and (3) December 31, 2024. The Company is also a “smaller reporting company,” meaning that the market value of its stock held by non-affiliates is less than $700.0 million and the Company’s annual revenue is less than $100.0 million during the most recently completed fiscal year. The Company may continue to be a smaller reporting company as long as either (i) the market value of its stock held by non-affiliates is less than $250.0 million or (ii) its annual revenue is less than $100.0 million during the most recently completed fiscal year and the market value of its stock held by non-affiliates is less than $700.0 million. If the Company is a smaller reporting company at the time it ceases to be an emerging growth company, the Company may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, the Company may choose to present only the two most recent fiscal years of audited financial statements in its Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair value measurements	3. Fair value measurements The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair value measurements as of September 30, 2023 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 186,165 $ — $ — $ 186,165 Total $ 186,165 $ — $ — $ 186,165 Marketable Securities: Corporate bonds $ — $ — $ — $ — Commercial paper — — — $ — US Government debt securities — 24,741 — $ 24,741 Total $ — $ 24,741 $ — $ 24,741 Fair value measurements as of December 31, 2022 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 111,927 $ — $ — $ 111,927 Total $ 111,927 $ — $ — $ 111,927 Marketable Securities: Corporate bonds $ — $ 34,527 $ — $ 34,527 Commercial paper — 7,978 — 7,978 US Government debt securities — 73,534 — 73,534 Total $ — $ 116,039 $ — $ 116,039 The Company’s cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy. The carrying value of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The Company’s assets with fair value categorized as Level 1 within the fair value hierarchy include money market funds. Money market funds are publicly traded mutual funds and are presented as cash equivalents on the consolidated balance sheets as of September 30, 2023 and December 31, 2022. The Company measures its marketable securities at fair value on a recurring basis and classifies those instruments within Level 2 of the fair value hierarchy. Marketable securities are valued using models or other valuation methodologies that use Level 2 inputs. These models are primarily industry-standard models that consider various assumptions, including time value, yield curve, volatility factors, default rates, current market and contractual prices for the underlying financial instruments, as well as other economic measures. Substantially all of these assumptions are observable in the marketplace, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. There were no transfers to Level 3 in the periods presented.

Marketable securities

Marketable securities	9 Months Ended
	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Marketable securities	4. Marketable securities The following table summarizes the Company’s marketable securities as of September 30, 2023 (in thousands): September 30, 2023 Amortized Cost Unrealized Gain Unrealized Loss Fair Value Marketable securities: Corporate bonds $ — $ — $ — $ — Commercial paper — — — — US Government debt securities 24,888 — ( 147 ) 24,741 Total $ 24,888 $ — $ ( 147 ) $ 24,741 The following table summarizes the Company’s marketable securities as of December 31, 2022 (in thousands): December 31, 2022 Amortized Cost Unrealized Gain Unrealized Loss Fair Value Marketable securities: Corporate bonds $ 34,662 $ — $ ( 135 ) $ 34,527 Commercial paper 8,019 — ( 41 ) 7,978 US Government debt securities 74,533 — ( 999 ) 73,534 Total $ 117,214 $ — $ ( 1,175 ) $ 116,039 The weighted average maturity of the Company’s marketable securities as of September 30, 2023 ranged from approximately 0.09 years to 0.42 years. As of December 31, 2022 , the weighted average maturity of the Company’s marketable securities ranged from approximately 0.18 years to 0.49 years. The Company did no t record an allowance for credit losses as of September 30, 2023 related to its marketable securities. Further, given the lack of significant change in the credit risk of these investments, the Company did not recognize any other-than-temporary impairment losses.

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	9 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Accrued and other current liabilities	5. Accrued and other current liabilities Accrued and other current liabilities consisted of the following (in thousands): September 30, December 31, 2023 2022 Accrued employee compensation costs $ 4,749 $ 5,754 Accrued professional costs 527 525 Accrued research and development costs 5,144 6,601 Current portion of operating lease liabilities 2,498 2,359 Other current liabilities 472 509 $ 13,390 $ 15,748

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	6. Commitments and contingencies Operating lease The Company determines whether an arrangement is a lease at inception. The Company accounts for a lease when it has the right to control the leased asset for a period of time while obtaining substantially all of the assets’ economic benefits. Operating lease right-of-use assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at the lease commencement date. The discount rate used to determine the present value of the lease payments is the Company’s incremental borrowing rate based on the information available at lease inception, as the Company did not have information to determine the rate implicit in the leases. Lease expense for operating leases is recognized on a straight-line basis over the reasonably assured lease term based on the total lease payments (which include initial direct costs and lease incentives). The expense is included in operating expenses in the consolidated statements of operations and comprehensive loss. The Company’s lease agreements also contain variable payments, primarily maintenance-related costs, which are expensed as incurred and not included in the measurement of the right-of-use assets and lease liabilities. In August 2018, the Company entered into an agreement to lease approximately 23,000 square feet of space for a term of three years . Lease terms are triple net lease commencing at $ 0.9 million per year, then with 3 % annual base rent increases plus operating expenses, real estate taxes, utilities and janitorial fees. The lease commencement date was December 10, 2018 . In September 2021, the Company entered into an agreement to extend the initial term of the 23,000 square foot lease for a period of three years commencing on December 15, 2021 and ending December 31, 2024 . In addition, this lease provides for the lease of an additional 15,000 square feet of rentable space beginning on April 1, 2022 and ending on December 31, 2024 . In December 2021, the Company recognized a right-of-use asset and operating lease liability of $ 3.5 million for the 23,000 square feet. On April 1, 2022, the Company recognized a right-of-use asset and operating lease liability of $ 1.8 million for the 15,000 square feet. In December 2018, the Company entered into an agreement to lease 2,485 square feet of space for an initial term of three years . The lease includes one renewal option for an additional two years , however, any time after the initial term the landlord may relocate the Company from the premises to a space reasonably comparable in size and utility. As the Company does not have the right to control the use of the identified asset after the initial term, the renewal option was excluded from the lease liability calculation. Lease terms commence at $ 0.2 million per annum, with 2.5 % annual base rent increases plus operating expenses, real estate taxes, utilities and janitorial fees. The lease commencement date was May 1, 2019 . In June 2021, the Company amended the agreement to extend the initial term of the 2,485 square foot lease for a period of three years commencing May 1, 2022 and ending April 30, 2025 . In addition, the amendment provided for the lease of an additional 2,357 square feet of rentable space beginning on July 6, 2021 and ending on April 30, 2025 . The amended lease provides the Company with the option to extend the term of the lease for an additional two years . In 2021, the Company recognized a right-of-use asset and operating lease liabilities of $ 0.7 million for the extension of the lease to April 30, 2025 and a right-of-use asset and operating lease liabilities of $ 0.8 million for the additional 2,357 square feet of rentable space. Future minimum lease payments under non-cancellable leases as of September 30, 2023 were as follows (in thousands): 2023 $ 634 2024 $ 2,608 2025 $ 172 Total lease payments $ 3,414 Less imputed interest ( 97 ) Present value of lease liabilities $ 3,317 Lease balances as of September 30, 2023 were as follows (in thousands): Operating right-of-use assets $ 3,084 Current portion of operating lease liabilities $ 2,498 Non-current portion of operating lease liabilities 819 Total operating lease liabilities $ 3,317 The weighted average remaining lease term and weighted average discount rate of the Company’s operating leases as of September 30, 2023 were as follows: Weighted average remaining lease term in years 1.3 Weighted average discount rate 4.70 % Lease expense incurred under operating leases was $ 0.6 million for the three months ended September 30, 2023 and for the three months ended September 30, 2022 was $ 0.6 million. Lease expenses incurred in the nine months ended September 30, 2023 were $ 1.8 million and for the nine months ended September 30, 2022 were $ 1.6 million. Scientific advisory board agreement In June 2020, the Company entered into a scientific advisory board agreement with a member of the Company’s board of directors, who is also an employee of Cold Spring Harbor Laboratory (“CSHL”), to provide scientific advisory services related to the Company’s Targeted Augmentation of Nuclear Gene Output (“TANGO”) antisense oligonucleotide technology and other antisense oligonucleotide technologies, as well as current and future therapeutic targets and programs. Following the expiration of the initial scientific agreement in June 2021 and a renewal agreement in June 2022, the parties entered into subsequent scientific board agreements on substantially the same terms. The Company did no t recognize any expense in the three months and nine months periods ended September 30, 2023 compared to no expense for the three months ended September 30, 2022 and recognized $ 0.02 million for the nine months ended September 30, 2022 for such scientific advisory services. The agreement has expired with no renewal put in place. License and research agreements In July 2015, the Company entered into a worldwide license agreement with CSHL (the “CSHL Agreement”), with respect to TANGO patents. Under the CSHL Agreement, the Company received an exclusive (except with respect to certain government rights and non-exclusive licenses), worldwide license under certain patents and applications relating to TANGO. The CSHL Agreement obligated the Company to make payments that are contingent upon certain milestones being achieved. The Company was also required to pay royalties, tiered based on the scope of patent coverage for each licensed product, ranging from a low-single digit percentage to a mid-single digit percentage on annual net sales. These royalty obligations applied on a licensed product-by-licensed product and country-by-country basis until the latest of (i) the expiration of the last valid claim of a CSHL patent covering the applicable licensed product or (ii) the expiration of any regulatory exclusivity for the applicable licensed product. In addition, if the Company sublicensed the rights under the CSHL Agreement, it was required to pay a maximum of twenty percent of the sublicense revenue to CSHL, which may have been reduced to a mid-teens or a mid-single digit percentage upon achievement of certain clinical milestones for the applicable licensed product. Finally, the Company was required to pay an annual license maintenance fee of $ 0.01 million, which amount is creditable against any owed royalty or milestone payments. The maximum aggregate potential milestone payments payable totaled approximately $ 0.90 million. Additionally, certain licenses under the CSHL Agreement required the Company to reimburse CSHL for certain past and ongoing patent related expenses, however there were no expenses related to these reimbursable patent costs during the years ended December 31, 2022 and 2021. After the completion of a 90-day waiting period, in May 2023 the Company terminated the CSHL Agreement. The Company does not expect the termination of the CSHL Agreement to have a significant impact on the intellectual property underlying any of its current product candidates, including STK-001 and STK-002, or its continued development of the TANGO platform. In April 2016, the Company entered into an exclusive, worldwide license agreement with the University of Southampton (the “Southampton Agreement”), whereby the Company acquired rights to foundational technologies related to the Company’s TANGO technology. Under the Southampton Agreement, the Company receives an exclusive, worldwide license under certain licensed patents and applications relating to TANGO. Under the Southampton Agreement, the Company may be obligated to make additional payments that are contingent upon certain milestones being achieved, as well as royalties on future product sales. These royalty obligations survive until the latest of (i) the expiration of the last valid claim of a licensed patent covering a subject product or (ii) the expiration of any regulatory exclusivity for the subject product in a country. In addition, if the Company sublicenses its rights under the Southampton Agreement, the Company is required to pay a mid-single digit percentage of the sublicense revenue to the University of Southampton. As of September 30, 2023 , the Company had paid $ 0.70 million under the Southampton Agreement as a result of entering into the Acadia Pharmaceuticals Inc. license and collaboration agreement in January 2022 (see Note 7). Additionally, certain licenses under the Southampton Agreement require the Company to reimburse the University of Southampton for certain past and ongoing patent related expenses. For the three months ended September 30, 2023 these expenses were $ 0.02 million compared to $ 0.03 million for the three months ended September 30, 2022, and for the nine months ended September 30, 2023 these expenses were $ 0.16 million compared to $ 0.17 million for the nine months ended September 30, 2022 .

License and collaboration agree

License and collaboration agreement with Acadia Pharmaceuticals Inc	9 Months Ended
	Sep. 30, 2023
License And Collaboration Agreement [Abstract]
License and collaboration agreement with Acadia Pharmaceuticals Inc	7. License and collaboration agreement with Acadia Pharmaceuticals Inc. In January 2022, the Company entered into a license and collaboration agreement with Acadia Pharmaceuticals Inc. (“Acadia”) for the discovery, development and commercialization of novel RNA-based medicines for the treatment of severe and rare genetic neurodevelopmental diseases of the central nervous system. The agreement focuses on the targets SYNGAP1, MECP2 (Rett syndrome), and an undisclosed neurodevelopmental target of mutual interest. In connection with each target, the Company will collaborate with Acadia to identify potential treatments for further development and commercialization as licensed products. With respect to SYNGAP1, the Company has agreed with Acadia to co-develop and co-commercialize licensed products for such target globally, and in connection therewith the Company granted to Acadia worldwide, co-exclusive (with Stoke) licenses for such licensed products. With respect to MECP2 and the neurodevelopmental target, the Company granted to Acadia worldwide, exclusive licenses to develop and commercialize licensed products for such targets. Pursuant to the terms of the agreement, the Company received an upfront payment of $ 60.0 million from Acadia. Acadia agreed to fund the research to identify potential licensed products for MECP2 and the neurodevelopmental target, and the Company will equally fund with Acadia the research to identify potential licensed products for SYNGAP1. The Company is eligible to receive up to $ 907.5 million in potential total milestone payments based upon the achievement of certain development, regulatory, first commercial sales and sales milestone events across the programs for the three targets, assuming each milestone were achieved at least once. With respect to licensed products for MECP2 and the neurodevelopmental target, the Company is also eligible to receive tiered royalties at percentages ranging from the mid-single digits to the mid-teens on future net sales by Acadia of licensed products worldwide. Royalties payable under the agreement are subject to standard royalty reductions. For SYNGAP1 licensed products that the Company is co-developing and co-commercializing, the Company will be responsible for 50% of the development and commercialization costs and will receive 50% of the profits from global commercialization. The Company is provided with a co-development and co-commercialization opt out option relating to the SYNGAP1 target indication at the Company’s discretion. Such opt-out would reduce development and commercialization milestones but would provide the Company with royalties on an escalating basis attributable to net sales milestones. Acadia agreement accounting At the commencement of the Acadia agreement, the Company identified three performance obligations consisting of pre-clinical research activities for each of the three targets, SYNGAP1, MECP2, and the undisclosed neurodevelopmental target. The exclusive or co-exclusive licenses granted to Acadia to conduct pre-clinical research activities on each of the three targets, and participation on each of the respective joint research committees were identified as promised services. However, the licenses granted to Acadia and the research activities were determined to be not distinct from each other, and therefore are considered a combined performance obligation for each of the three targets. Participation on each of the joint research committees was determined to be quantitatively and qualitatively immaterial in the context of the arrangement with Acadia. The Company is recognizing the transaction price for the pre-clinical research activities for each of the three targets over time as the research services are provided. The transfer of control to Acadia occurs over this time period, and in management’s judgment, is the best measure of progress towards satisfying the performance obligation. An input method is used that measures the cost incurred to date in satisfying each of the three research activities in relation to the estimated total projected cost of each of the research activities to fulfill the respective obligations. The cumulative effect of revisions to estimated costs and/or the transaction price to complete the research performance obligations will be recorded in the period in which changes are identified and amounts can be reasonably estimated. During the quarter ended June 30, 2023, the Company updated its estimate of the total effort it expected to expend to satisfy its performance obligations under the Acadia collaboration. As a result, the Company recorded a cumulative catch-up adjustment of $( 5.3 ) million which resulted in a reversal of revenue during the quarter ended June 30, 2023. The adjustment was recorded because the total cost to complete the work associated with the three targets increased. The Company recognized revenue related to the Acadia collaboration of $ 3.3 million during the quarter ended September 30, 2023 and $ 6.0 million for the nine months ended September 30, 2023. Milestone payments that are not within the control of the Company, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. For other milestones, the Company evaluated factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. Milestones that are outside of the Company’s or Acadia’s control will not be recognized until such milestones are achieved. As to the other milestones, to date, no milestone payments have been included in the transaction price due to the uncertainty as to whether these milestones will be achieved. The Company will at the end of each reporting period reevaluate the probability of achievement of all milestones subject to constraint and, if necessary, adjust its estimate of the overall transaction price for each of the research activities on the three targets. Any such adjustments will be recorded on a cumulative catch-up basis. As of September 30, 2023 , the Company had $ 49.5 million in upfront consideration associated with the Acadia agreement relating to performance obligations that are unsatisfied or partially unsatisfied.

Equity Incentive Plans

Equity Incentive Plans	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Equity incentive plans	8. Equity incentive plans In June 2019, the Company’s board of directors and stockholders approved the 2019 Equity Incentive Plan (the “2019 Plan”) which became effective on June 17, 2019 and replaced the Company’s 2014 Equity Incentive Plan (the “2014 Plan”). In addition to the shares of common stock reserved for future issuance under the 2014 Plan that were added to the 2019 Plan upon its effective date, the Company initially reserved 2,200,000 shares of common stock for issuance under the 2019 Plan. The number of shares reserved for issuance under the Company’s 2019 Plan will increase automatically on January 1 of each of 2020 through 2029 by the number of shares equal to 4 % of the aggregate number of outstanding shares of the Company’s common stock as of the immediately preceding December 31, or a lesser number as may be determined by the Company’s board of directors. In April 2023, the Company’s board of directors adopted the Stoke Therapeutics, Inc. 2023 Inducement Plan (the “2023 Plan”). As permitted by Nasdaq stock market rules, the Company’s stockholders were not required to approve the Inducement Plan. The Inducement Plan provides for up to 1,000,000 shares of the Company’s common stock under awards granted to newly hired employees. An “award” is any right to receive common stock of the Company through nonstatutory stock options or restricted stock units. As of September 30, 2023 , there were no shares available for future issuance under the 2014 Plan, 479,511 shares were available under the 2019 Plan and 973,100 shares were available under the 2023 Plan. During the three months ended September 30, 2023 , the Company granted options to purchase 96,340 shares of common stock to its employees. The options vest up to four years and are exercisable at a per share price equal to the fair value of the common stock on the grant date. During the three months ended September 30, 2023 , the Company did no t grant any restricted stock units to its employees. Stock-based compensation As of September 30, 2023, there was $ 49.2 million of unrecognized compensation cost related to unvested stock-based compensation arrangements granted under the 2019 and 2023 Plans. The compensation is expected to be recognized over a weighted average period of 3.45 years as of September 30, 2023. Stock-based compensation expense recorded as research and development and general and administrative expenses in the accompanying consolidated statements of operations and comprehensive loss is as follows (in thousands): Three Months Ended September 30, Nine Months End September 30, 2023 2022 2023 2022 Research and development $ 2,576 $ 2,327 $ 7,607 $ 6,613 General and administrative 3,976 3,599 11,592 10,451 $ 6,552 $ 5,926 $ 19,199 $ 17,064 2019 Employee stock purchase plan In June 2019, the Company adopted the 2019 Employee Stock Purchase Plan (“ESPP”), which became effective on June 18, 2019. The Company initially reserved 315,000 shares of common stock for sale under the ESPP. At September 30, 2023 , the Company had 1,282,528 shares available for issuance under the ESPP plan. The average grant date fair value per share under the ESPP plan was $ 9.88 for 2023. The total ESPP stock-based compensation expense for the three and nine months ended September 30, 2023 was $ 0.1 million and $ 0.3 million, respectively, and for the three and nine months ended September 30, 2022 was $ 0.1 million and $ 0.3 million, respectively. The number of shares reserved for issuance under the ESPP will increase automatically on January 1st of each of the first ten calendar years following the first offering date by the number of shares equal to the lesser of 1 % of the total outstanding shares of the Company’s common stock as of the immediately preceding December 31 or a lower amount determined by the Company’s board of directors. The aggregate number of shares issued over the term of the ESPP will not exceed 3,150,000 shares of the Company’s common stock.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Net loss per share	9. Net loss per share The following table summarizes the computation of basic and diluted net loss per share of the Company (in thousands except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Numerator: Net loss $ ( 24,542 ) $ ( 26,111 ) $ ( 77,741 ) $ ( 75,412 ) Denominator: Weighted-average number of common shares, 44,266,017 39,420,310 43,669,987 38,716,615 Net loss per share, basic and diluted $ ( 0.55 ) $ ( 0.66 ) $ ( 1.78 ) $ ( 1.95 ) The Company’s potential dilutive securities, which include common stock options and ESPP purchase rights, have been excluded from the computation of diluted net loss per share as the effect would be anti-dilutive. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at period end, from the computation of diluted net loss per share indicated because including them would have had an anti-dilutive effect: September 30, 2023 2022 Outstanding options to purchase common stock/restricted stock units 10,247,560 7,388,700

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income taxes	10. Income taxes The Company did no t record an income tax benefit in its consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022 as it is more likely than not that the Company will not recognize the federal and state deferred tax benefits generated by its losses. The Company has provided a valuation allowance for the full amount of its net deferred tax assets as of September 30, 2023 and December 31, 2022, as management has determined it is more likely than not that any future benefit from deductible temporary differences and net operating loss and tax credit carryforwards would not be realized. The Company did no t record any amounts for unrecognized tax benefits as of September 30, 2023 or December 31, 2022.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent events	11. Subsequent events Since September 30, 2023, we sold approximately 361,000 shares of our common stock and received approximately $ 1.4 million after deducting commissions related to the Sales Agreement. We may terminate this at-the-market program at any time, pursuant to its terms.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of presentation and consolidation The accompanying unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and include the accounts of the Company and its wholly-owned subsidiary. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). All intercompany transactions between and among its consolidated subsidiary have been eliminated.
Unaudited Interim Financial Information	Unaudited interim financial information The accompanying interim unaudited consolidated financial statements and related disclosures are unaudited and have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Company’s consolidated financial statements and related notes as of and for the year ended December 31, 2022, which was filed with the SEC on March 6, 2023. The Company’s financial information as of September 30, 2023 and for the three and nine months ended September 30, 2023 and 2022 is unaudited, but in the opinion of management, all adjustments, consisting only of normal recurring adjustments, considered necessary for a fair presentation of the financial position, results of operations and cash flows at the dates and for the periods presented of the results of these interim periods have been included. The balance sheet information as of December 31, 2022 was derived from audited consolidated financial statements. The results of the Company’s operations for any interim period are not necessarily indicative of the results that may be expected for any other interim period or for a full fiscal year.
Use of Estimates	Use of estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, equity, revenue, expenses and disclosure of contingent assets and liabilities. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from those estimates.
Cash, Cash Equivalents and Restricted Cash	Cash, cash equivalents and restricted cash The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. The Company deposits its cash in checking, sweep and money market accounts. At September 30, 2023, restricted cash consisted of money market accounts collateralizing letters of credit issued as security deposits in connection with the Company’s leases of its corporate facilities. Cash and cash equivalents, and restricted cash in the consolidated statements of cash flows consists of the following (in thousands): As of September 30, 2023 2022 Cash and cash equivalents $ 189,977 $ 113,396 Restricted cash - long-term 569 569 Total cash, cash equivalents and restricted cash $ 190,546 $ 113,965
Emerging Growth Company and Smaller Reporting Company Status	Emerging growth company and smaller reporting company status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, the Company’s unaudited consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. The Company will remain an emerging growth company until the earliest of (1) the last day of its first fiscal year (a) in which the Company has total annual gross revenues of at least $1.235 billion, or (b) in which the Company is deemed to be a large accelerated filer, which means the market value of its common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30 th , (2) the date on which it has issued more than $1.0 billion in non-convertible debt securities during the prior three-year period and (3) December 31, 2024. The Company is also a “smaller reporting company,” meaning that the market value of its stock held by non-affiliates is less than $700.0 million and the Company’s annual revenue is less than $100.0 million during the most recently completed fiscal year. The Company may continue to be a smaller reporting company as long as either (i) the market value of its stock held by non-affiliates is less than $250.0 million or (ii) its annual revenue is less than $100.0 million during the most recently completed fiscal year and the market value of its stock held by non-affiliates is less than $700.0 million. If the Company is a smaller reporting company at the time it ceases to be an emerging growth company, the Company may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, the Company may choose to present only the two most recent fiscal years of audited financial statements in its Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Tables)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents and Restricted Cash	Cash and cash equivalents, and restricted cash in the consolidated statements of cash flows consists of the following (in thousands): As of September 30, 2023 2022 Cash and cash equivalents $ 189,977 $ 113,396 Restricted cash - long-term 569 569 Total cash, cash equivalents and restricted cash $ 190,546 $ 113,965

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Financial Assets Measured at Fair Value on Recurring Basis and Level of Fair Value Hierarchy Utilized	The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair value measurements as of September 30, 2023 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 186,165 $ — $ — $ 186,165 Total $ 186,165 $ — $ — $ 186,165 Marketable Securities: Corporate bonds $ — $ — $ — $ — Commercial paper — — — $ — US Government debt securities — 24,741 — $ 24,741 Total $ — $ 24,741 $ — $ 24,741 Fair value measurements as of December 31, 2022 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 111,927 $ — $ — $ 111,927 Total $ 111,927 $ — $ — $ 111,927 Marketable Securities: Corporate bonds $ — $ 34,527 $ — $ 34,527 Commercial paper — 7,978 — 7,978 US Government debt securities — 73,534 — 73,534 Total $ — $ 116,039 $ — $ 116,039

Marketable securities (Tables)

Marketable securities (Tables)	9 Months Ended
	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Summary of Marketable securities	The following table summarizes the Company’s marketable securities as of September 30, 2023 (in thousands): September 30, 2023 Amortized Cost Unrealized Gain Unrealized Loss Fair Value Marketable securities: Corporate bonds $ — $ — $ — $ — Commercial paper — — — — US Government debt securities 24,888 — ( 147 ) 24,741 Total $ 24,888 $ — $ ( 147 ) $ 24,741 The following table summarizes the Company’s marketable securities as of December 31, 2022 (in thousands): December 31, 2022 Amortized Cost Unrealized Gain Unrealized Loss Fair Value Marketable securities: Corporate bonds $ 34,662 $ — $ ( 135 ) $ 34,527 Commercial paper 8,019 — ( 41 ) 7,978 US Government debt securities 74,533 — ( 999 ) 73,534 Total $ 117,214 $ — $ ( 1,175 ) $ 116,039

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Schedule of Accrued and Other Current Liabilities	Accrued and other current liabilities consisted of the following (in thousands): September 30, December 31, 2023 2022 Accrued employee compensation costs $ 4,749 $ 5,754 Accrued professional costs 527 525 Accrued research and development costs 5,144 6,601 Current portion of operating lease liabilities 2,498 2,359 Other current liabilities 472 509 $ 13,390 $ 15,748

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases	Future minimum lease payments under non-cancellable leases as of September 30, 2023 were as follows (in thousands): 2023 $ 634 2024 $ 2,608 2025 $ 172 Total lease payments $ 3,414 Less imputed interest ( 97 ) Present value of lease liabilities $ 3,317
Summary of Lease Balances	Lease balances as of September 30, 2023 were as follows (in thousands): Operating right-of-use assets $ 3,084 Current portion of operating lease liabilities $ 2,498 Non-current portion of operating lease liabilities 819 Total operating lease liabilities $ 3,317
Summary of Weighted Average Remaining Lease Term and Weighted Average Discount Rate of Operating Leases	The weighted average remaining lease term and weighted average discount rate of the Company’s operating leases as of September 30, 2023 were as follows: Weighted average remaining lease term in years 1.3 Weighted average discount rate 4.70 %

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Stock-based Compensation Expense	Stock-based compensation expense recorded as research and development and general and administrative expenses in the accompanying consolidated statements of operations and comprehensive loss is as follows (in thousands): Three Months Ended September 30, Nine Months End September 30, 2023 2022 2023 2022 Research and development $ 2,576 $ 2,327 $ 7,607 $ 6,613 General and administrative 3,976 3,599 11,592 10,451 $ 6,552 $ 5,926 $ 19,199 $ 17,064

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss Per Share	The following table summarizes the computation of basic and diluted net loss per share of the Company (in thousands except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Numerator: Net loss $ ( 24,542 ) $ ( 26,111 ) $ ( 77,741 ) $ ( 75,412 ) Denominator: Weighted-average number of common shares, 44,266,017 39,420,310 43,669,987 38,716,615 Net loss per share, basic and diluted $ ( 0.55 ) $ ( 0.66 ) $ ( 1.78 ) $ ( 1.95 )
Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The Company excluded the following potential common shares, presented based on amounts outstanding at period end, from the computation of diluted net loss per share indicated because including them would have had an anti-dilutive effect: September 30, 2023 2022 Outstanding options to purchase common stock/restricted stock units 10,247,560 7,388,700

Nature of the Business - Additi

Nature of the Business - Additional Information (Details) - USD ($)	1 Months Ended	9 Months Ended
	May 31, 2022	Sep. 30, 2023
Nature Of Business [Line Items]
Entity incorporation state name		DE
Base Prospectus
Nature Of Business [Line Items]
Maximum aggregate offering price	$ 400,000,000
Sales Agreement Prospectus
Nature Of Business [Line Items]
Maximum aggregate offering price	$ 150,000,000
Stock issued during period, shares		$ 4,600,000
Proceeds from issuance of common stock net of commissions		$ 44,700,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Recent Accounting Pronouncements - Schedule of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Cash and cash equivalents	$ 189,977	$ 113,556	$ 113,396
Restricted cash - long-term	569	569	569
Total cash, cash equivalents and restricted cash	$ 190,546	$ 114,125	$ 113,965	$ 145,464

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on Recurring Basis and Level of Fair Value Hierarchy Utilized (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities	$ 24,741	$ 116,039
Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		34,527
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		7,978
US Government Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities	24,741	73,534
Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents	186,165	111,927
Total Marketable Securities	24,741	116,039
Fair Value, Recurring | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents	186,165	111,927
Fair Value, Recurring | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents	186,165	111,927
Fair Value, Recurring | Level 1 | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents	186,165	111,927
Fair Value, Recurring | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities	24,741	116,039
Fair Value, Recurring | Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		34,527
Fair Value, Recurring | Corporate Bonds | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		34,527
Fair Value, Recurring | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		7,978
Fair Value, Recurring | Commercial Paper | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities		7,978
Fair Value, Recurring | US Government Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities	24,741	73,534
Fair Value, Recurring | US Government Debt Securities | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Marketable Securities	$ 24,741	$ 73,534

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair value assets, transfers to level 3, amount	$ 0	$ 0

Marketable securities - Summary

Marketable securities - Summary of Marketable securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Marketable Securities, Amortized Cost	$ 24,888	$ 117,214
Marketable Securities, Unrealized Loss	(147)	(1,175)
Marketable Securities, Fair Value	24,741	116,039
Corporate Bonds
Marketable Securities [Line Items]
Marketable Securities, Amortized Cost		34,662
Marketable Securities, Unrealized Loss		(135)
Marketable Securities, Fair Value		34,527
Commercial Paper
Marketable Securities [Line Items]
Marketable Securities, Amortized Cost		8,019
Marketable Securities, Unrealized Loss		(41)
Marketable Securities, Fair Value		7,978
US Government Debt Securities
Marketable Securities [Line Items]
Marketable Securities, Amortized Cost	24,888	74,533
Marketable Securities, Unrealized Loss	(147)	(999)
Marketable Securities, Fair Value	$ 24,741	$ 73,534

Marketable securities - Additio

Marketable securities - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Allowance for credit losses	$ 0
Minimum
Marketable Securities [Line Items]
Weighted average maturity marketable securities period	1 month 2 days	2 months 4 days
Maximum
Marketable Securities [Line Items]
Weighted average maturity marketable securities period	5 months 1 day	5 months 26 days

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities - Schedule of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued employee compensation costs	$ 4,749	$ 5,754
Accrued professional costs	527	525
Accrued research and development costs	5,144	6,601
Current portion of operating lease liabilities	2,498	2,359
Other current liabilities	472	509
Total accrued and other current liabilities	$ 13,390	$ 15,748

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)

1 Months Ended

3 Months Ended

9 Months Ended

12 Months Ended

Sep. 30, 2021 ft²

Jun. 30, 2021 ft²

Dec. 31, 2018 USD ($) ft² Option

Aug. 31, 2018 USD ($) ft²

Jul. 31, 2015

Sep. 30, 2023 USD ($)

Sep. 30, 2022 USD ($)

Sep. 30, 2023 USD ($)

Sep. 30, 2022 USD ($)

Dec. 31, 2022 USD ($)

Dec. 31, 2021 USD ($)

Apr. 01, 2022 USD ($)

Commitments And Contingencies [Line Items]

Area of space subject to operating lease | ft²

2,485

23,000

Operating lease term

3 years

3 years

Operating lease cost per year

$ 200,000

$ 900,000

Annual base rent increase percentage for operating lease

2.50%

3%

Operating lease commencement date

May 01, 2019

Dec. 10, 2018

Operating lease right-of-use assets

$ 3,084,000

$ 3,084,000

$ 4,753,000

Operating lease liabilities

3,317,000

3,317,000

Number of options to renewal operating lease term | Option

1

Operating lease, renewal term

2 years

CSHL Agreement

Commitments And Contingencies [Line Items]

Percentage of maximum required payment of sublicense revenue

20%

Annual license maintenance fee

10,000

Maximum aggregate potential milestone payments payable

900,000

$ 900,000

Expenses related to reimbursable patent costs

$ 0

$ 0

CSHL agreement termination description

After the completion of a 90-day waiting period, in May 2023 the Company terminated the CSHL Agreement.

Southampton Agreement

Commitments And Contingencies [Line Items]

Expenses related to reimbursable patent costs

20,000

$ 30,000

$ 160,000

$ 170,000

Payment for license and collaboration agreement

700,000

Member of Board of Directors

Commitments And Contingencies [Line Items]

Scientific advisory services expenses

0

0

0

20,000

ASU 2016-02

Commitments And Contingencies [Line Items]

Operating leases expense

$ 600,000

$ 600,000

$ 1,800,000

$ 1,600,000

Lease Commencement on December 15, 2021

Commitments And Contingencies [Line Items]

Area of space subject to operating lease | ft²

23,000

Operating lease term

3 years

Operating lease commencement date

Dec. 15, 2021

Operating lease expiration date

Dec. 31, 2024

Operating lease right-of-use assets

3,500,000

Operating lease liabilities

3,500,000

Lease Commencement on April 2022

Commitments And Contingencies [Line Items]

Area of space subject to operating lease | ft²

15,000

Operating lease commencement date

Apr. 01, 2022

Operating lease expiration date

Dec. 31, 2024

Operating lease right-of-use assets

$ 1,800,000

Operating lease liabilities

$ 1,800,000

Lease Extension End Date April 30, 2025

Commitments And Contingencies [Line Items]

Area of space subject to operating lease | ft²

2,485

Operating lease term

3 years

Operating lease commencement date

May 01, 2022

Operating lease expiration date

Apr. 30, 2025

Operating lease right-of-use assets

700,000

Operating lease liabilities

700,000

Operating lease, renewal term

2 years

Area of additional space subject to operating lease | ft²

2,357

Additional operating lease commencement date

Jul. 06, 2021

Additional operating lease expiration date

Apr. 30, 2025

Additional operating lease, right-of-use asset

800,000

Additional operating lease, liabilities

$ 800,000

Operating lease, option to extend

The amended lease provides the Company with the option to extend the term of the lease for an additional two years.

Operating lease, existence of option to extend [true false]

true

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Future minimum lease payments under non-cancellable leases
2023	$ 634
2024	2,608
2025	172
Total lease payments	3,414
Less imputed interest	(97)
Present value of lease liabilities	$ 3,317

Commitments and Contingencies_3

Commitments and Contingencies - Summary of Lease Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Operating lease right-of-use assets	$ 3,084	$ 4,753
Current portion of operating lease liabilities	$ 2,498	$ 2,359
Operating Lease Liability Current Statement Of Financial Position Extensible List	Liabilities, Current
Non-current portion of operating lease liabilities	$ 819
Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List	Other long term liabilities
Total operating lease liabilities	$ 3,317

Commitments and Contingencies_4

Commitments and Contingencies - Summary of Weighted Average Remaining Lease Term and Weighted Average Discount Rate of Operating Leases (Details)	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Weighted average remaining lease term in years	1 year 3 months 18 days
Weighted average discount rate	4.70%

License and collaboration agr_2

License and collaboration agreement with Acadia Pharmaceuticals Inc - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended			9 Months Ended
	Jan. 31, 2022	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
License And Collaboration Agreement [Line Items]
Revenue		$ 3,308		$ 2,905	$ 5,978	$ 9,137
Acadia Pharmaceuticals Inc.
License And Collaboration Agreement [Line Items]
Upfront Payment received	$ 60,000
Potential milestone payments receivable	$ 907,500
Cumulative catch-up adjustment, estimate of transaction price			$ (5,300)
Revenue		$ 3,300			6,000
Remaining upfront consideration					$ 49,500

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Apr. 30, 2023	Jun. 30, 2019	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option granted to purchase shares			96,340
Unrecognized compensation cost			$ 49,200		$ 49,200
Expected weighted average period					3 years 5 months 12 days
Stock based compensation expense			$ 6,552	$ 5,926	$ 19,199	$ 17,064
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted			0
2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock reserved for issuance		2,200,000
Percentage of increase in reserved common shares		4%
Number of common shares available for future issuance			479,511		479,511
2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares available for future issuance			0		0
2019 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock reserved for issuance		315,000
Number of common shares available for future issuance			1,282,528		1,282,528
Average grant date fair value per share under the plan					$ 9.88
Stock based compensation expense			$ 100	$ 100	$ 300	$ 300
2019 ESPP | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock reserved for issuance		3,150,000
Percentage of increase in reserved common shares		1%
2023 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares available for future issuance			973,100		973,100
2023 Inducement Plan | Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option granted to purchase shares	1,000,000

Equity Incentive Plans - Summar

Equity Incentive Plans - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	$ 6,552	$ 5,926	$ 19,199	$ 17,064
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	2,576	2,327	7,607	6,613
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	$ 3,976	$ 3,599	$ 11,592	$ 10,451

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net loss	$ (24,542)	$ (30,654)	$ (22,545)	$ (26,111)	$ (24,652)	$ (24,649)	$ (77,741)	$ (75,412)
Denominator:
Weighted-average number of common shares, basic	44,266,017			39,420,310			43,669,987	38,716,615
Weighted-average number of common shares, diluted	44,266,017			39,420,310			43,669,987	38,716,615
Net loss per share, basic	$ (0.55)			$ (0.66)			$ (1.78)	$ (1.95)
Net loss per share, diluted	$ (0.55)			$ (0.66)			$ (1.78)	$ (1.95)

Net Loss Per Share - Schedule_2

Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Outstanding options to purchase common stock/restricted stock units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share, amount	10,247,560	7,388,700

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income tax benefit	$ 0	$ 0	$ 0	$ 0
Unrecognized tax benefits	$ 0		$ 0		$ 0

Subsequent events - Additional

Subsequent events - Additional Information (Details) - Sales Agreement Prospectus $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($) shares
Subsequent Event [Line Items]
Issuance of common stock, Shares | shares	361,000
Received deducting commissions related to sales agreement | $	$ 1.4