Mineralys Therapeutics (MLYS) 10-K 21 Mar 24 2023 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 15, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-41614
Entity Registrant Name	MINERALYS THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-1966887
Entity Address, Address Line One	150 N. Radnor Chester Rd
Entity Address, Address Line Two	Suite F200
Entity Address, City or Town	Radnor
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19087
City Area Code	888
Local Phone Number	378-6240
Title of 12(b) Security	0.0001
Trading Symbol	MLYS
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction	false
Entity Shell Company	false
Entity Public Float			$ 239.9
Entity Common Stock, Shares Outstanding		49,631,159
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement relating to its 2024 annual meeting of stockholders (the 2024 Proxy Statement) are incorporated by reference into Part III of this Annual Report on Form 10-K (Annual Report) where indicated.
Entity Central Index Key	0001933414
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	Ernst & Young LLP
Auditor Location	Denver, Colorado
Auditor Firm ID	42

Balance Sheets

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 49,304	$ 87,701
Investments	187,263	22,409
Prepaid and other current assets	12,536	2,701
Total current assets	249,103	112,811
Investments, noncurrent	2,482	0
Other assets	51	1,631
Total assets	251,636	114,442
Current liabilities:
Accounts payable	601	1,907
Accrued liabilities	9,881	6,160
Total current liabilities	10,482	8,067
Commitments and contingencies (Note 4)
Stockholders’ equity (deficit):
Common stock, $0.0001 par value, 500,000,000 and 319,000,000 shares authorized and 41,133,916 and 6,419,238 shares issued and outstanding as of December 31, 2023 and 2022, respectively	4	1
Additional paid-in capital	365,858	540
Accumulated deficit	(124,708)	(52,810)
Total stockholders’ equity (deficit)	241,154	(52,269)
Total liabilities, convertible preferred stock, and stockholders’ equity (deficit)	251,636	114,442
Series A Convertible Preferred Stock
Current liabilities:
Convertible preferred stock	0	40,987
Series B Convertible Preferred Stock
Current liabilities:
Convertible preferred stock	$ 0	$ 117,657

Balance Sheets (Parentheticals)

Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Common stock par value (in USD per share)	$ 0.0001	$ 0.0001
Common stock shares authorized (in shares)	500,000,000	319,000,000
Common stock shares outstanding (in shares)	41,133,916	6,419,238
Common stock shares issued (in shares)	41,133,916	6,419,238
Series A Convertible Preferred Stock
Convertible preferred stock par value (in USD per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized (in shares)	0	86,332,216
Convertible preferred stock, shares outstanding (in shares)	0	86,332,216
Convertible preferred stock, shares issued (in shares)	0	86,332,216
Convertible preferred stock, liquidation preference	$ 0	$ 41,180
Series B Convertible Preferred Stock
Convertible preferred stock par value (in USD per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized (in shares)	0	136,510,868
Convertible preferred stock, shares outstanding (in shares)	0	136,510,868
Convertible preferred stock, shares issued (in shares)	0	136,510,868
Convertible preferred stock, liquidation preference	$ 0	$ 118,000

Statements of Operations

Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating expenses:
Research and development	$ 70,361	$ 26,250
General and administrative	14,296	5,229
Total operating expenses	84,657	31,479
Loss from operations	(84,657)	(31,479)
Interest income, net	12,756	1,676
Other income	3	4
Total other income, net	12,759	1,680
Net loss	$ (71,898)	$ (29,799)
Basic net loss per share attributable to common stockholders (in USD per share)	$ (1.99)	$ (5.77)
Diluted net loss per share attributable to common stockholders (in USD per share)	$ (1.99)	$ (5.77)
Basic weighted-average shares used to compute net loss per share attributable to common stockholders (in shares)	36,188,254	5,167,296
Diluted weighted-average shares used to compute net loss per share attributable to common stockholders (in shares)	36,188,254	5,167,296

Statements of Convertible Prefe

Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock	Series B Convertible Preferred Stock	Common Stock	Additional Paid-In-Capital	Accumulated Deficit
Beginning balance, convertible preferred stock (in shares) at Dec. 31, 2021		61,180,259	0
Beginning balance, convertible preferred stock at Dec. 31, 2021		$ 28,996	$ 0
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of convertible preferred stock, net of issuance costs (in shares)		25,151,957	136,510,868
Issuance of convertible preferred stock, net of issuance costs		$ 11,991	$ 117,657
Ending balance, convertible preferred stock (in shares) at Dec. 31, 2022		86,332,216	136,510,868
Ending balance, convertible preferred stock at Dec. 31, 2022		$ 40,987	$ 117,657
Beginning balance (in shares) at Dec. 31, 2021				5,441,980
Beginning balance at Dec. 31, 2021	$ (22,925)			$ 1	$ 85	$ (23,011)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of restricted stock awards (in shares)				977,258
Stock-based compensation	455				455
Net loss	$ (29,799)					(29,799)
Ending balance (in shares) at Dec. 31, 2022	6,419,238			6,419,238
Ending balance at Dec. 31, 2022	$ (52,269)			$ 1	540	(52,810)
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)		(86,332,216)	(136,510,868)
Conversion of preferred stock to common stock upon closing of initial public offering		$ (40,987)	$ (117,657)
Ending balance, convertible preferred stock (in shares) at Dec. 31, 2023		0	0
Ending balance, convertible preferred stock at Dec. 31, 2023		$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)				20,637,415
Conversion of preferred stock to common stock upon closing of initial public offering	158,644			$ 2	158,642
Issuance of common stock from initial public offering, net of issuance costs (in shares)				13,800,000
Issuance of common stock from initial public offering, net of issuance costs	$ 201,359			$ 1	201,358
Issuance of common stock from stock option exercises (in shares)	268,534			268,534
Issuance of common stock from stock option exercises	$ 194				194
Issuance of common stock for cash under employee stock purchase plan (in shares)				8,729
Issuance of common stock for cash under employee stock purchase plan	64				64
Stock-based compensation	5,060				5,060
Net loss	$ (71,898)					(71,898)
Ending balance (in shares) at Dec. 31, 2023	41,133,916			41,133,916
Ending balance at Dec. 31, 2023	$ 241,154			$ 4	$ 365,858	$ (124,708)

Statements of Convertible Pre_2

Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Common Stock
Issuance of common stock in initial public offering, issuance costs	$ 19,441
Series A Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs		$ 7
Series B Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs		$ 343

Statements of Cash Flows

Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023		Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss		$ (71,898)		$ (29,799)
Adjustments to reconcile net loss to net cash used in operating activities:
Accretion of discount on held-to-maturity securities		(6,865)		(649)
Stock-based compensation		5,060		455
Changes in operating assets and liabilities:
Accrued interest receivable		(355)		0
Prepaid and other current assets		(9,530)		(2,240)
Accounts payable and accrued liabilities		2,415		3,012
Net cash used in operating activities		(81,173)		(29,221)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of marketable securities		(347,972)		(71,759)
Maturity of marketable securities		187,500		50,000
Net cash used in investing activities		(160,472)		(21,759)
CASH FLOWS FROM FINANCING ACTIVITIES:
Issuance of common stock in initial public offering, net of offering costs		202,990		(1,629)
Proceeds from stock option exercises		194		0
Proceeds from the issuance of common stock for cash under employee stock purchase plan		64		0
Net cash provided by financing activities		203,248		128,019
Net increase (decrease) in cash and cash equivalents		(38,397)		77,039
Cash, cash equivalents, and restricted cash - beginning		87,701	[1]	10,662
Cash, cash equivalents, and restricted cash - ending	[1]	49,304		87,701
Supplement Disclosure of Non-Cash Financing Activities:
Conversion of convertible preferred stock to common stock upon closing of initial public offering		159,180		0
Deferred offering costs included in accounts payable and accrued liabilities		0		360
Series A Convertible Preferred Stock
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the issuance of convertible preferred stock, net of offering costs		0		11,991
Series B Convertible Preferred Stock
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the issuance of convertible preferred stock, net of offering costs		$ 0		$ 117,657
[1] Cash and cash equivalents as of December 31, 2023 exclude investments of $189.7 million. Cash, cash equivalents, and investments amounted to $239.0 million as of December 31, 2023.

Statements of Cash Flows (Paren

Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Statement of Cash Flows [Abstract]
Investments	$ 189,745	$ 22,409
Cash, cash equivalents, and investments	$ 239,000

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business Mineralys Therapeutics, Inc. (the Company) is a clinical-stage biopharmaceutical company focused on developing medicines to target diseases driven by abnormally elevated aldosterone. The Company’s clinical-stage product candidate, lorundrostat, is a proprietary, orally administered, aldosterone synthase inhibitor that the Company is initially developing for the treatment of cardiorenal conditions affected by abnormally elevated aldosterone, including hypertension and chronic kidney disease. The Company has initiated a pivotal clinical program of lorundrostat for the treatment of uncontrolled or resistant hypertension and initiated a Phase 2 trial for lorundrostat in hypertensive patients with Stage 2 to 3b chronic kidney disease. The Company was incorporated as a Delaware corporation in May 2019, and it is headquartered in Radnor, Pennsylvania. The Company’s operations to date have been limited to business planning, raising capital, in-licensing lorundrostat, conducting preclinical and clinical trials, and other research and development. Initial Public Offering On February 14, 2023, the Company completed an initial public offering (IPO) of 13,800,000 shares of its common stock, which included the exercise in full by the underwriters of their option to purchase 1,800,000 additional shares, at a public offering price of $16.00 per share. The net proceeds to the Company from the IPO were $201.4 million, net of underwriting discounts, commissions, and offering costs. Reverse Stock Split On February 1, 2023, the Company effected a one-for-10.798 reverse stock split of its issued and outstanding shares of common stock, par value $0.0001 per share, and a proportional adjustment to the existing conversion ratio of the Company’s preferred stock (the Reverse Stock Split). Accordingly, all share and per-share amounts for all periods presented in the accompanying financial statements and notes thereto have been adjusted to reflect this Reverse Stock Split. Liquidity and Capital Resources Since its inception, the Company has not generated any revenue from product sales or other sources and has incurred significant operating losses and negative cash flows from operations. The Company’s primary uses of cash to date have been to fund research and development activities, business planning, establishing and maintaining the Company’s intellectual property portfolio, hiring personnel, raising capital, and providing general and administrative support for these operations. As of December 31, 2023, the Company had an accumulated deficit of $124.7 million and cash, cash equivalents, and investments of $239.0 million. For the year ended December 31, 2023, the Company had a net loss of $71.9 million and net cash used in operating activities of $81.2 million.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The financial statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP), which include all adjustments necessary for the fair presentation of the Company’s financial position, results of operations, and cash flows for the periods presented. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Updates of the Financial Accounting Standards Board (FASB). The Company’s management performed an evaluation of its activities through the date of filing of these financial statements and concluded that there are no subsequent events requiring disclosure, other than as disclosed. Emerging Growth Company Status The Company is an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act (JOBS Act), and may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies. The Company may take advantage of these exemptions until the last day of the fiscal year following the fifth anniversary of its initial public offering or such earlier time as the Company is no longer an “emerging growth company.” Section 107 of the JOBS Act provides that an “emerging growth company” can take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards and as a result of this election, its financial statements may not be comparable to companies that comply with public company effective dates. The Company may take advantage of these exemptions up until the last day of the fiscal year following the fifth anniversary of its initial public offering or such earlier time that it is no longer an “emerging growth company.” Segment Information The Company operates in one operating segment for the purposes of assessing performance and making operating decisions and, accordingly, no segment disclosures have been presented herein. All assets are held in the United States. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Estimates have been used in the following areas, among others: research and development accruals, fair value of the Company’s common stock prior to the closing of the Company’s IPO, and income taxes. Cash, Cash Equivalents, and Restricted Cash All highly liquid investments that have maturities of 90 days or less at the date of purchase are classified as cash equivalents. As of December 31, 2023 and 2022, the Company did not have any restricted cash balances. The following table provides a reconciliation of cash and cash equivalents as reported in the statement of cash flows to the balance sheets (in thousands): December 31, 2023 2022 Cash $ 643 $ 2,872 Cash equivalents 48,661 84,829 Total cash and cash equivalents $ 49,304 $ 87,701 The Company’s cash and cash equivalents balances as of December 31, 2023 include cash balances and amounts held primarily in interest-bearing money market accounts. As of December 31, 2021, the Company had $50 thousand classified as restricted cash, which is reported in the 2022 opening cash, cash equivalents, and restricted cash balance reported in the statements of cash flows. Concentration of Credit Risk The Company has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts, or other hedging arrangements. Financial instruments that potentially subject the Company to concentrations of credit risk primarily consist of cash balances in several accounts with two financial institutions which, from time to time, are in excess of federally insured limits. Risks and Uncertainties The Company has not yet generated any revenue from the sale of its products and is subject to all of the risks and uncertainties that are typically faced by biopharmaceutical companies that devote substantially all of their efforts to research and development and clinical trials and do not yet have commercial products. The Company expects to continue incurring losses for the foreseeable future. Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC Topic 820, Fair Value Measurement, establishes a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1 – quoted prices in active markets for identical assets and liabilities • Level 2 – other significant observable inputs (including quoted prices for similar assets and liabilities, interest rates, credit risk, etc.) • Level 3 – significant unobservable inputs (including the Company’s own assumptions in determining the fair value of assets and liabilities) For certain financial instruments, including cash and cash equivalents, prepaid expenses, accounts payable, and certain accrued liabilities, the recorded amount approximates estimated fair value due to their relatively short maturity period. Refer to Note 3. “ Fair Value of Financial Instruments ” for additional details of the Company’s financial instruments. Investments The Company generally invests its excess cash in money market funds and investment-grade short- and long-term fixed-income debt securities, such as U.S. Treasury bills. Such investments are included in cash and cash equivalents, current investments, and investments - noncurrent in the balance sheets. The Company determines the appropriate classification of short-term and long-term securities at the time of purchase and re-evaluates such designation as of each balance sheet date. Securities are classified as held-to-maturity when the Company has the positive intent and ability to hold the securities to maturity. Held-to-maturity securities are carried at amortized cost, adjusted for the accretion of discounts using the interest method. The Company invested in marketable securities during the years ended December 31, 2023 and 2022, and no impairment charges were recorded. For held-to-maturity investments, the Company periodically reviews each individual security position that has an unrealized loss, or impairment, to determine if that impairment is other-than-temporary. If the Company believes an impairment of a security position is other than temporary, based on available quantitative and qualitative information as of the report date, the loss will be recognized within other income, net in the Company’s statements of operations and a new cost basis in the investment is established. 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 are expensed immediately as a charge to operating expenses in the statement of operations. Deferred offering costs as of December 31, 2023 and 2022 were $0 and $1.6 million, respectively. Such costs are classified in other assets on the balance sheets. Convertible Preferred Stock The Company records convertible preferred stock at fair value on the dates of issuance, net of issuance costs. Upon the occurrence of certain events that are outside the Company’s control, including a deemed liquidation event, holders of the convertible preferred stock can cause redemption for cash. Therefore, the convertible preferred stock is classified outside of stockholders’ deficit on the balance sheets as events triggering the redemption for cash were not solely within the Company’s control. The carrying values of the convertible preferred stock are adjusted to their liquidation preferences if and when it becomes probable that such a liquidation event will occur. In February 2023, the Company’s convertible preferred stock converted into shares of the Company’s common stock of which carrying value at the date of conversion was converted to permanent equity, which is described in more detail in Note 6. “ Capital Stock .” Research and Development Expenses Research and development costs, both internal and external, are expensed as incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided to the Company by its clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. The Company’s research and development expenses consist primarily of clinical trial expenses, consulting and employee-related costs, and costs associated with required regulatory filings, licenses, and fees. Non-refundable advance payments for goods and services that will be used in future research and development activities are capitalized and recorded as expense in the period that the Company receives the goods or when services are performed. Assets acquired (or in-licensed) that are utilized in research and development that have no alternative future use are expensed as incurred. Commitments and Contingencies From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and can be reasonably estimated. The Company expects that contingencies related to regulatory approval milestones will only become probable once such regulatory outcome is achieved. Stock-Based Compensation The Company accounts for its stock-based compensation awards in accordance with ASC Topic 718, Compensation – Stock Compensation (ASC 718). ASC 718 requires all stock-based payments to employees, including grants of employee stock options, to be recognized in the statements of operations based on their fair values. The Company’s stock-based awards are subject only to service-based vesting conditions. The Company measures restricted common stock awards using the difference, if any, between the purchase price per share of the award and the fair value of the Company’s common stock at the date of the grant or modification. The Company estimates the fair value of its stock option awards using the Black-Scholes option pricing model, which requires the input of assumptions, including (i) the expected stock price volatility, (ii) the calculation of expected term of the award, (iii) the risk-free interest rate, and (iv) expected dividends. Volatility — Due to the Company’s limited operating history and a lack of company-specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar publicly-traded companies. The Company believes that the companies in the group were most representative of the Company and had characteristics similar to its own, including stage of product development, a focus on the life sciences industry, and other economic and industry characteristics. Expected Term — The Company uses the simplified method to calculate the expected term, as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term for options granted, and utilized the contractual term for options granted. Risk-Free Interest Rate — The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected life of the stock options. Expected Dividends — To date, the Company has not issued any dividends and does not expect to issue dividends over the life of the options and therefore has estimated the dividend yield to be zero. Subsequent to the closing of the Company’s IPO, the Company determines the fair market value of its common stock using the closing price of its common stock as reported on the Nasdaq Global Select Market. Prior to the closing of the Company’s IPO, there was no public market for the Company’s common stock, and the Company determined the fair value of the shares of its common stock underlying its share-based awards by considering a number of objective and subjective factors, including third-party valuations of the Company’s common stock, the valuation of comparable companies, the Company’s operating and financial performance, and general and industry-specific economic outlook, among other factors. The assumptions underlying these valuations represented management’s best estimate, with the assistance of a third-party valuation specialist, which involved inherent uncertainties and the application of management’s judgment. As a result, if the Company had used different assumptions or estimates, the fair value of the Company’s common stock and its stock-based compensation expense could have been materially different. Compensation expense related to awards is recognized on a straight-line basis by recognizing the grant date fair value over the associated service period of the award, which is generally the vesting term. Management evaluates its award grants and modifications and will adjust the fair value if any are determined to be spring-loaded. The Company accounts for forfeitures as they occur. Net Loss Per Share The Company’s basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period. The diluted net loss per share attributable to common stockholders is computed by giving effect to all potential common stock equivalents outstanding for the period determined using the treasury stock method. For purposes of this calculation, convertible preferred stock and stock options to purchase common stock are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is anti-dilutive. The following table sets forth the potential common shares excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive: Year Ended December 31, 2023 2022 Outstanding options 2,540,279 1,365,442 Unvested restricted stock awards 1,007,930 1,199,136 Convertible preferred stock (as converted into common stock) — 20,637,415 Total 3,548,209 23,201,993 Income Taxes Income taxes are recorded in accordance with ASC Topic 740, Income Taxes (ASC 740), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities and for loss and credit carryforwards using enacted tax rates anticipated to be in effect for the year in which the differences are expected to reverse. Valuation allowances are provided if, based on the weight of available evidence, it is more likely than not that some or all the deferred tax assets will not be realized. The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that some or all of the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based on the technical merits of the tax position, as well as consideration of the available facts and circumstances. As of December 31, 2023 and 2022, the Company does not have any significant uncertain tax positions. If the Company were to incur interest and penalties on uncertain tax positions, it would classify them as income tax expense. Recently Issued Accounting Pronouncements

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments The following table presents financial instruments measured at fair value on a recurring basis based on the fair value hierarchy as of December 31, 2023 and 2022 (in thousands): December 31, 2023 2022 Level 1 Assets Cash equivalents Money market funds $ 48,661 $ 84,829 There were no transfers within the fair value hierarchy during the periods presented. The following methods and assumptions were used by the Company in estimating the fair values of each class of financial instrument disclosed herein: Money Market Funds —The carrying amounts of money market funds reported as cash and cash equivalents in the balance sheets approximate their fair values due to their short-term nature. The fair values of money market funds are determined by Level 1 inputs utilizing quoted prices (unadjusted) in active markets for identical assets. U.S. Treasury Bills—As of December 31, 2023 and 2022, the Company had short- and/or long-term U.S. Treasury bills. Fair values of these securities are determined by Level 2 inputs utilizing quoted prices (unadjusted) in active markets for similar assets. The following table presents held-to-maturity U.S. Treasury bills information as of each reported date (in thousands): As of December 31, 2023 Balance Sheet Location Original Maturities Amortized Estimated Investments between 3 and 12 months $ 187,263 $ 187,293 Investments, noncurrent greater than 1 year 2,482 2,486 Total $ 189,745 $ 189,779 As of December 31, 2022 Balance Sheet Location Original Maturities Amortized Estimated Investments between 3 and 6 months $ 22,409 $ 22,386

Commitment and Contingencies

Commitment and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies License Agreement with Mitsubishi Tanabe In July 2020, the Company entered into a license agreement (the Mitsubishi License) with Mitsubishi Tanabe Pharmaceutical Company (Mitsubishi Tanabe), pursuant to which Mitsubishi Tanabe granted the Company an exclusive, worldwide, royalty-bearing, sublicensable license under Mitsubishi Tanabe’s patent and other intellectual property rights to exploit products incorporating lorundrostat (formerly MT-4129) (Lorundrostat Products) for the prevention, treatment, diagnosis, detection, monitoring, or predisposition testing with respect to indications, diseases, and conditions in humans. Pursuant to the Mitsubishi License, the Company paid Mitsubishi Tanabe a $1.0 million upfront fee and development milestone payments of $9.0 million in the aggregate. The Company has remaining obligations to pay Mitsubishi Tanabe commercial milestone payments of up to $155.0 million in the aggregate upon first commercial sale and upon meeting certain annual sales targets, as well as additional commercial milestone payments of up to $10.0 million for a second indication. Additionally, the Company is obligated to pay Mitsubishi Tanabe tiered royalties at percentages ranging from the mid-single-digits to ten percent (10%) of aggregate net sales of each Lorundrostat Product on a Lorundrostat Product-by-Lorundrostat Product and country-by-country basis, until the later of (i) the expiration of the last-to-expire valid Mitsubishi Tanabe patent claim covering a Lorundrostat Product, (ii) ten years from the first commercial sale of a Lorundrostat Product, or (iii) the expiration of regulatory exclusivity in such country. Such royalties are subject to reduction under specified conditions, including lack of patent coverage and generic competition. The Company is obligated to use commercially reasonable efforts to conduct and complete the development activities and to file for regulatory approval for at least one Lorundrostat Product in a major market country and consider in good faith developing at least one Lorundrostat Product in a non-major market country. If the Company elects to sublicense its rights under the Mitsubishi License to a third party with respect to exploitation of lorundrostat or any Lorundrostat Product in certain countries in Asia, the Company has agreed to negotiate such a sublicense first, for a specified period of time, with Mitsubishi Tanabe, if Mitsubishi Tanabe notifies the Company that it would like to obtain such a sublicense. The Company also agreed not to commercialize any competing product prior to three years following the first commercial sale of the first Lorundrostat Product in any country without Mitsubishi Tanabe’s prior consent. Unless terminated earlier, the Mitsubishi License will continue until the expiration of all of the Company’s royalty obligations to Mitsubishi Tanabe. The Company may terminate the Mitsubishi License for any or no reason upon 90 or 180 days’ prior written notice to Mitsubishi Tanabe depending on whether the Lorundrostat Product has received regulatory approval. Mitsubishi Tanabe may terminate the Mitsubishi License if the Company has not initiated regulatory consultation for the first global clinical trials of lorundrostat in at least one major market country within a specified amount of time or if the Company or its affiliates or sublicensees initiate a challenge to the patent rights licensed to the Company by Mitsubishi Tanabe. In addition, either party may terminate the Mitsubishi License in the event of an uncured material breach by or bankruptcy of the other party, subject to certain notice and cure periods, or upon the other party’s bankruptcy or insolvency. The Company incurred $9.0 million and $0 of research and development expenses related to the Mitsubishi License during the years ended December 31, 2023 and 2022, respectively. The development milestones of $4.0 million and $5.0 million were achieved in March 2023 and December 2023, respectively, and related to the Company’s initiation of its pivotal clinical program of lorundrostat. These payments satisfied in full the aggregate development milestone payments described above. Litigation Liabilities for loss contingencies arising from claims, assessments, litigation, fines, penalties, and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. From time to time, the Company may become involved in legal proceedings arising in the ordinary course of business. The Company was not subject to any material legal proceedings during the years ended December 31, 2023 and 2022, and no material legal proceedings are currently pending or threatened. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners, and other parties with respect to certain matters including, but not limited to, losses arising from breach of such agreements or intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with officers of the Company and members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations in its financial statements as of December 31, 2023 and 2022.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consisted of the following (in thousands): December 31, 2023 2022 Research and development expenses $ 7,122 $ 4,846 Compensation and benefits 1,599 665 Professional fees and other 1,160 649 Total $ 9,881 $ 6,160

Capital Stock

Capital Stock	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Capital Stock	Capital Stock As of December 31, 2023, the Company had reserved authorized shares of common stock for future issuance as follows: December 31, 2023 Shares available for grant under the 2023 Plan 3,206,629 Common stock options outstanding 2,540,279 Shares available for grant under the ESPP 391,271 Total 6,138,179 In connection with the closing of the IPO in February 2023, the Company’s board of directors approved an amendment to the Company’s amended and restated certificate of incorporation (the Restated Certificate). The Restated Certificate amended and restated the Company’s amended and restated certificate of incorporation, in its entirety to, among other things, increase the authorized number of shares of common stock to 500,000,000 shares and authorize 50,000,000 shares of undesignated preferred stock that may be issued from time to time by the Company’s board of directors in one or more series. Preferred Stock Offerings In February 2021, the Company entered into a Series A redeemable convertible preferred stock agreement (the Series A Purchase Agreement). From February 2021 to April 2021, the Company issued 50,311,827 shares of Series A Preferred Stock at $0.477 per share for net proceeds of $23.8 million. Additionally, in February 2021, the Company’s convertible notes and related accrued interest converted into 10,868,432 shares of Series A Preferred Stock. The Series A Purchase Agreement provided for an additional closing for the Series A purchasers for the issuance of up to 25,151,957 shares of Series A Preferred Stock, at a purchase price of $0.477 per share for aggregate cash proceeds of $12.0 million, upon the achievement of the Milestone (as defined in the Series A Purchase Agreement) or a waiver of the Milestone by the requisite holders. In January 2022, the Company achieved the Milestone under the Series A Purchase Agreement and sold an aggregate of 25,151,957 shares of Series A Preferred Stock under the Series A Purchase Agreement to certain existing investors, members of the Company’s board of directors and affiliates of members of its board of directors, at a purchase price of $0.477 per share for aggregate net proceeds of approximately $12.0 million. In June 2022, the Company entered into a Series B convertible preferred stock agreement with certain investors, including members of the Company’s board of directors and affiliates of members of its board of directors, pursuant to which the Company issued and sold to such investors an aggregate of 136,510,868 shares of Series B Preferred Stock at a purchase price of $0.8644 per share for aggregate net proceeds of approximately $117.7 million. Immediately prior to the closing of the IPO, 86,332,216 shares of Series A Preferred Stock and 136,510,868 shares of Series B Preferred Stock converted into 20,637,415 shares of the Company’s common stock, and the carrying value of Series A Preferred Stock and Series B Preferred Stock was converted to permanent equity. Private Placement Offering On February 7, 2024, the Company entered into a securities purchase agreement (the Purchase Agreement) with the purchasers named therein (the Purchasers), for the private placement (the Private Placement) of (i) 8,339,169 shares (the Shares) of the Company’s common stock at a price of $13.50 per Share, and (ii) with respect to certain Purchasers, pre-funded warrants to purchase an aggregate of 549,755 shares of common stock (the Pre-Funded Warrants) in lieu of shares of common stock, at a purchase price of $13.499 per Pre-Funded Warrants (the shares of common stock issuable upon exercise of the Pre-Funded Warrants, the Warrant Shares). The aggregate gross proceeds for the Private Placement were approximately $120.0 million, before deducting offering expenses. The Company expects to use the net proceeds from the Private Placement to fund the research and development of lorundrostat and for working capital and general corporate purposes. Each Pre-Funded Warrant has an exercise price of $0.001 per share of common stock, is immediately exercisable on the date of issuance, and will not expire. Under the terms of the Pre-Funded Warrants, the Company may not effect the exercise of any portion of any Pre-Funded Warrant, and a holder will not have the right to exercise any portion of any Pre-Funded Warrant, which, upon giving effect to such exercise, would cause a holder (together with its affiliates) to own more than a specified beneficial ownership limitation of either 4.99%, 9.99% or 19.99% (as selected by such holder prior to the issuance of the Pre-Funded Warrant) of the number of shares of common stock outstanding immediately after giving effect to such exercise, as such percentage ownership is determined in accordance with the terms of the Pre-Funded Warrants. However, any holder may increase or decrease such percentage to any other percentage not in excess of 19.99%, provided that any increase in such percentage shall not be effective until 61 days after such notice is delivered to the Company. Pursuant to the Purchase Agreement, the Company agreed to file a registration statement with the Securities and Exchange Commission (the SEC) within 60 days after the closing of the Private Placement (subject to certain exceptions) for purposes of registering the resale of the Shares and the Warrant Shares, to use its reasonable best efforts to have such registration statement declared effective within the time period set forth in the Purchase Agreement, and to keep such registration statement effective until the earliest of (i) the time as all of the Shares and Warrant Shares purchased by the Purchasers pursuant to the terms of the Purchase Agreement have been sold pursuant to the registration statement, or (ii) such time as the Shares and Warrant Shares become eligible for resale by non-affiliates without any volume limitations or other restrictions pursuant to Rule 144 under the Securities Act of 1933, as amended, or any other rule of similar effect.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation 2023 Incentive Award Plan In February 2023, the Company’s board of directors adopted and stockholders approved the 2023 Incentive Award Plan that became effective upon the closing of the IPO (2023 Plan), under which the Company may grant stock options, restricted stock awards (RSAs), dividend equivalents, restricted stock units, stock appreciation rights, and other stock or cash-based awards to its employees, consultants, and directors. The number of shares of the Company’s common stock initially available for issuance under awards granted pursuant to the 2023 Plan was the sum of (i) 4,650,000 shares of the Company’s common stock, plus (ii) any shares subject to outstanding awards under the 2020 Plan described below as of the effective date of the 2023 Plan that become available for issuance under the 2023 Plan thereafter in accordance with its terms. The number of shares initially available for issuance will be increased on January 1 of each calendar year beginning in 2024 and ending in 2033, by an amount equal to the lesser of (i) 4% of the shares of the Company’s common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as determined by the Company’s board of directors. No more than 100,000,000 shares of the Company’s common stock may be issued upon the exercise of incentive stock options under the 2023 Plan. Shares issued under the 2023 Plan may be authorized but unissued shares, shares purchased on the open market, or treasury shares. 2020 Equity Incentive Plan On July 7, 2020, the board of directors adopted, and the Company’s stockholders approved, the 2020 Equity Incentive Plan. The 2020 Equity Incentive Plan, as amended and restated (the 2020 Plan), provided for the grant of incentive stock options to employees of the Company, and for the grant of non-statutory stock options, RSAs, restricted stock unit awards, and other forms of stock awards to employees, directors, and consultants of the Company. Subsequent to the closing of the IPO, no additional awards will be granted under the 2020 Plan. However, the 2020 Plan will continue to govern the terms and conditions of the outstanding awards granted under it. Shares of the Company’s common stock subject to awards granted under the 2020 Plan that expire, lapse, or are terminated, exchanged for cash, surrendered, repurchased, or forfeited following the effective date of the 2020 Plan will be available for issuance under the 2023 Plan in accordance with its terms. The board of directors or a designated committee of the board of directors is responsible for the administration of the 2023 Plan, and previously the 2020 Plan, and determines the term, exercise price, and vesting terms of each award. Under the terms of existing awards, all stock option grants expire ten years from the grant date. New option grants could not have an exercise price less than 100% of the fair market value of the Company’s common stock on the grant date and generally vested over a period of four years. The Company issues new shares of common stock upon exercise of stock options or issuance of RSAs. As of December 31, 2023, the Company had the following balances by plan: Options Unvested Shares Available 2023 Plan 1,451,985 — 3,206,629 2020 Plan 1,088,294 1,007,930 — Total 2,540,279 1,007,930 3,206,629 Stock Options The following is a summary of the Company’s stock option activity under its 2023 Plan and 2020 Plan: Shares Weighted-Average Exercise Price Total Intrinsic Value Weighted-Average Remaining Contractual Life (Years) Options outstanding as of December 31, 2021 527,387 $ 0.67 $ 105 9.4 Options granted 838,055 $ 1.18 Options outstanding as of December 31, 2022 1,365,442 $ 0.98 $ 15,561 9.1 Options granted 1,588,235 $ 15.19 Options exercised (268,534) $ 0.73 Options forfeited or expired (144,864) $ 14.85 Options outstanding as of December 31, 2023 2,540,279 $ 9.10 $ 8,291 8.8 Options vested and exercisable as of December 31, 2023 464,934 $ 2.74 $ 3,113 8.2 As of December 31, 2023, the Company had $15.2 million of unrecognized share-based compensation expense related to stock option awards that is expected to be recognized over a weighted-average period of approximately 1.5 years. For the years ended December 31, 2023 and 2022, the total fair value of options vested was $1.5 million and $0.1 million, respectively. The aggregate intrinsic value of options exercised for the years ended December 31, 2023 and 2022 was $3.2 million and $0, respectively. The weighted-average grant date fair value per share for options granted during the years ended December 31, 2023 and 2022 was $12.41 and $2.12, respectively. The following table presents the weighted-average assumptions used in the Black-Scholes option pricing model to determine the fair value of stock options granted during the following periods: Year Ended December 31, 2023 2022 Exercise price $ 15.19 $ 1.18 Expected term (years) 6.01 years 6.07 years Expected stock price volatility 104.6 % 92.2 % Risk-free rate of interest 3.9 % 3.0 % Expected dividend yield — % — % On February 14, 2024, the Company’s board of directors approved the grant under the 2023 Plan of stock options to purchase an aggregate of 1,469,600 shares of its common stock to certain of the Company’s employees at an exercise price equal of $14.25. Restricted Stock Awards RSAs granted by the Company have varying vesting terms depending on the terms of the grant. Holders of unvested RSAs have the same rights as those of common stockholders including voting rights and non-forfeitable dividend rights. However, ownership of unvested RSAs cannot be transferred until vested. Upon a participant’s termination of continuous service for any reason, any shares subject to RSAs held by the participant that have not vested as of such termination date may be forfeited to or repurchased by the Company. The following is a summary of the Company’s RSA activity under its 2023 Plan and 2020 Plan: Shares Weighted-Average Grant Date Fair Value Unvested as of December 31, 2021 337,639 $ 0.0108 Granted 977,258 $ 1.7512 Vested (115,761) $ 0.0010 Unvested as of December 31, 2022 1,199,136 $ 1.4290 Vested (191,206) $ 0.3493 Unvested as of December 31, 2023 1,007,930 $ 1.6338 As of December 31, 2023, the Company had $1.0 million of unrecognized share-based compensation expense related to RSAs that is expected to be recognized over a weighted-average period of approximately 1.3 years. For the years ended December 31, 2023 and 2022, the total fair value of RSAs vested was $0.1 million in each year. 2023 Employee Stock Purchase Plan In February 2023, the Company’s board of directors and stockholders approved the 2023 Employee Stock Purchase Plan (ESPP), which became effective upon the closing of the Company’s IPO. The ESPP permits eligible employees who elect to participate in an offering under the ESPP to have up to a specified percentage of their eligible compensation withheld, subject to certain limitations, to purchase shares of common stock pursuant to the ESPP. A total of 400,000 shares of the Company’s common stock was initially reserved for issuance under the ESPP. The first ESPP offering period commenced on July 1, 2023, with each new six-month offering period beginning each January 1 and July 1. ESPP purchases of common stock occur at a price equal to 85% of the lower of (i) the closing price on the first trading day of the offering period or (ii) the closing price on the last trading day of the offering period. As of December 31, 2023, the Company had 391,271 shares available for issuance and 8,729 cumulative shares had been issued under the ESPP. In addition, the number of shares available for issuance under the ESPP will be annually increased on January 1 of each calendar year beginning in 2024 and ending in and including 2033, by an amount equal to the lesser of (i) 1% of the shares outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by the Company’s board of directors, provided that no more than 15,000,000 shares of the Company’s common stock may be issued under the ESPP. Total stock-based compensation expense reported in the statements of operations was allocated as follows (in thousands): Year Ended December 31, 2023 2022 Research and development $ 2,263 $ 200 General and administrative 2,797 255 Total $ 5,060 $ 455

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes There was no current or deferred income tax expense or benefit for the years ended December 31, 2023 and 2022, due to the Company’s net loss and increases in its deferred tax asset valuation allowance. The components of the Company’s deferred tax assets are as follows (in thousands): December 31, 2023 2022 Net operating loss carryforwards $ 7,890 $ 5,738 Research and development credit carryforwards 5,671 1,357 Capitalized research and development costs 15,037 5,367 Intangible assets 2,048 270 Other 857 183 Total deferred tax assets 31,503 12,915 Valuation allowance (31,503) (12,915) Deferred tax assets, net of valuation allowance $ — $ — The Company has established a valuation allowance against its net deferred tax assets due to the uncertainty surrounding the realization of such assets, which are dependent on future earnings, if any, the timing and amount of which are uncertain. The Company periodically evaluates the recoverability of the deferred tax assets. Valuation allowances are provided against deferred tax assets when, based on all available evidence, it is considered more likely than not that some portion or all of the recorded deferred tax assets will not be realized in future periods. When realization of the deferred tax asset is more likely than not to occur, the benefit related to the deductible temporary differences attributable to operations is recognized as a reduction of income tax expense. The Company’s valuation allowance increased by approximately $18.6 million and $7.6 million for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023 and 2022, the Company had federal net operating loss (NOL) carryforwards of $35.0 million and $25.7 million available to reduce future taxable income, respectively. The federal NOL carryforward has no expiration as a result of the Tax Cuts and Jobs Act of 2017. As of December 31, 2023 and 2022, the Company had $8.6 million and $5.3 million, respectively, of state NOL carryforwards that begin expiring in 2041. As of December 31, 2023 and 2022, the Company had federal and state research and development tax credit carryforwards of $5.7 million and $1.4 million, respectively, to reduce future taxable income. The federal research and development tax credit carryforwards begin to expire in 2040. Research and development tax credit carryforwards associated with California carry forward indefinitely. Research and development tax credit carryforwards associated with other states begin expiring in 2038. The Internal Revenue Code (IRC) Sections 382 and 383 limit annual use of NOL and research and development credit carryforwards in the event a cumulative change in ownership of more than 50% occurs within a three-year period. The Company has not yet completed an ownership change analysis pursuant to IRC Section 382. If a requisite ownership change has occurred or occurs, the amount of remaining tax attribute carryforwards available to offset taxable income and income tax expense in future years may be restricted or eliminated. If eliminated, the related asset would be removed from deferred tax assets with a corresponding reduction in the valuation allowance. Due to the existence of the valuation allowance, limitations created by future ownership changes, if any, will not impact the Company’s effective tax rate. The Company’s effective tax rate for the years ended December 31, 2023 and 2022 was 0%. A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows for the years ended: December 31, 2023 2022 Statutory federal income tax rate 21.00 % 21.00 % State income taxes, net of federal tax benefits (0.29) 1.69 Research and development credits 5.74 2.81 Permanent items and other (0.60) (0.11) Change in valuation allowance (25.85) (25.39) Total provision for income taxes — % — % The Company files income tax returns in the U.S. Federal jurisdiction and various state and local jurisdictions. As of December 31, 2023, all years remained subject to examination by tax authorities. Uncertain tax positions are evaluated based on the facts and circumstances that exist at each reporting period. Subsequent changes in judgment based on new information may lead to changes in recognition, derecognition, and measurement. Adjustment may result, for example, upon resolution of an issue with the taxing authorities or expiration of a statute of limitations barring an assessment for an issue. The Company recognizes a tax benefit from an uncertain tax position when it is more-likely-than-not that it will be sustained upon examination by tax authorities. As of December 31, 2023 and 2022, the Company had $1.1 million and $0.3 million, respectively, in unrecognized tax benefits, which would not affect the effective tax rate if recognized. During the year ended December 31, 2023, the Company’s unrecognized tax benefits increased by approximately $0.8 million related to current year tax positions. The Company does not anticipate any significant changes in its unrecognized tax benefits over the next 12 months. The Company’s policy is to recognize interest expense and penalties related to income tax matters in income tax expense. As of December 31, 2023 and 2022, the Company had no accrued interest or penalties related to uncertain tax positions. The following table summarizes the changes to the Company’s unrecognized tax benefits for the years ended December 31, 2023 and 2022 (in thousands): Year Ended December 31, 2023 2022 Beginning balance $ 261 $ 118 Additions related to current year positions 781 143 Additions related to prior year positions 34 — Ending balance $ 1,076 $ 261

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net loss	$ (71,898)	$ (29,799)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	12 Months Ended
	Dec. 31, 2023 shares	Dec. 31, 2023 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		The material terms of these Rule 10b5-1 trading arrangements are described below: Name and Title Action Taken Type of Trading Arrangement Nature of Trading Arrangement Duration of Trading Arrangement Number of Securities David Rodman, M.D., Chief Medical Officer Adoption 11/14/2023 Trading plan intended to satisfy the affirmative defense conditions of Exchange Act Rule 10b5-1(c) Sale of the Company’s common stock pursuant to the terms of the plan 2/8/24 - 12/31/2024 (1) Adam Levy, Chief Financial Officer Adoption 11/14/2023 Trading plan intended to satisfy the affirmative defense conditions of Exchange Act Rule 10b5-1(c) Sale of the Company’s common stock pursuant to the terms of the plan 6/11/2024 - 1/30/2026 (2) ________ (1) The executive’s Rule 10b5-1 trading arrangement provides for the sale of up to (i) 10,034 shares of common stock and (ii) 45,436 shares of common stock subject to a stock option award granted to Dr. Rodman that vests ratably over time. (2) The executive’s Rule 10b5-1 trading arrangement provides for the sale of up to 172,117 shares of common stock subject to a restricted stock award granted to Mr. Levy that vests ratably over time.
Rule 10b5-1 Arrangement Adopted	true
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
David Rodman M.D. [Member]
Trading Arrangements, by Individual
Name	David Rodman, M.D.
Title	Chief Medical Officer
Adoption Date	Adoption 11/14/2023
Arrangement Duration	327 days
Adam Levy [Member]
Trading Arrangements, by Individual
Name	Adam Levy
Title	Chief Financial Officer
Adoption Date	Adoption 11/14/2023
Arrangement Duration	598 days
Aggregate Available	172,117	172,117
David Rodman M.D. Trading Arrangement, Common Stock [Member] | David Rodman M.D. [Member]
Trading Arrangements, by Individual
Aggregate Available	10,034	10,034
David Rodman M.D. Trading Arrangement, Common Stock Subject to Stock Option Award [Member] | David Rodman M.D. [Member]
Trading Arrangements, by Individual
Aggregate Available	45,436	45,436

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The financial statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP), which include all adjustments necessary for the fair presentation of the Company’s financial position, results of operations, and cash flows for the periods presented. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Updates of the Financial Accounting Standards Board (FASB). The Company’s management performed an evaluation of its activities through the date of filing of these financial statements and concluded that there are no subsequent events requiring disclosure, other than as disclosed. Emerging Growth Company Status The Company is an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act (JOBS Act), and may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies. The Company may take advantage of these exemptions until the last day of the fiscal year following the fifth anniversary of its initial public offering or such earlier time as the Company is no longer an “emerging growth company.” Section 107 of the JOBS Act provides that an “emerging growth company” can take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards and as a result of this election, its financial statements may not be comparable to companies that comply with public company effective dates. The Company may take advantage of these exemptions up until the last day of the fiscal year following the fifth anniversary of its initial public offering or such earlier time that it is no longer an “emerging growth company.”
Segment Information	Segment Information
Use of Estimates	Use of Estimates
Cash, Cash Equivalents, and Restricted Cash	Cash, Cash Equivalents, and Restricted Cash
Cash, Cash Equivalents, and Restricted Cash	Cash, Cash Equivalents, and Restricted Cash
Concentration of Credit Risk	Concentration of Credit Risk
Fair Value Measurements	Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC Topic 820, Fair Value Measurement, establishes a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1 – quoted prices in active markets for identical assets and liabilities • Level 2 – other significant observable inputs (including quoted prices for similar assets and liabilities, interest rates, credit risk, etc.) • Level 3 – significant unobservable inputs (including the Company’s own assumptions in determining the fair value of assets and liabilities) For certain financial instruments, including cash and cash equivalents, prepaid expenses, accounts payable, and certain accrued liabilities, the recorded amount approximates estimated fair value due to their relatively short maturity period. Refer to Note 3. “ Fair Value of Financial Instruments ” for additional details of the Company’s financial instruments.
Investments	Investments The Company generally invests its excess cash in money market funds and investment-grade short- and long-term fixed-income debt securities, such as U.S. Treasury bills. Such investments are included in cash and cash equivalents, current investments, and investments - noncurrent in the balance sheets. The Company determines the appropriate classification of short-term and long-term securities at the time of purchase and re-evaluates such designation as of each balance sheet date. Securities are classified as held-to-maturity when the Company has the positive intent and ability to hold the securities to maturity. Held-to-maturity securities are carried at amortized cost, adjusted for the accretion of discounts using the interest method. The Company invested in marketable securities during the years ended December 31, 2023 and 2022, and no impairment charges were recorded. For held-to-maturity investments, the Company periodically reviews each individual security position that has an unrealized loss, or impairment, to determine if that impairment is other-than-temporary. If the Company believes an impairment of a security position is other than temporary, based on available quantitative and qualitative information as of the report date, the loss will be recognized within other income, net in the Company’s statements of operations and a new cost basis in the investment is established.
Deferred Offering Costs	Deferred Offering Costs
Convertible Preferred Stock	Convertible Preferred Stock
Research and Development Expenses	Research and Development Expenses Research and development costs, both internal and external, are expensed as incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided to the Company by its clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. The Company’s research and development expenses consist primarily of clinical trial expenses, consulting and employee-related costs, and costs associated with required regulatory filings, licenses, and fees. Non-refundable advance payments for goods and services that will be used in future research and development activities are capitalized and recorded as expense in the period that the Company receives the goods or when services are performed. Assets acquired (or in-licensed) that are utilized in research and development that have no alternative future use are expensed as incurred.
Commitments and Contingencies	Commitments and Contingencies From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and can be reasonably estimated. The Company expects that contingencies related to regulatory approval milestones will only become probable once such regulatory outcome is achieved.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for its stock-based compensation awards in accordance with ASC Topic 718, Compensation – Stock Compensation (ASC 718). ASC 718 requires all stock-based payments to employees, including grants of employee stock options, to be recognized in the statements of operations based on their fair values. The Company’s stock-based awards are subject only to service-based vesting conditions. The Company measures restricted common stock awards using the difference, if any, between the purchase price per share of the award and the fair value of the Company’s common stock at the date of the grant or modification. The Company estimates the fair value of its stock option awards using the Black-Scholes option pricing model, which requires the input of assumptions, including (i) the expected stock price volatility, (ii) the calculation of expected term of the award, (iii) the risk-free interest rate, and (iv) expected dividends. Volatility — Due to the Company’s limited operating history and a lack of company-specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar publicly-traded companies. The Company believes that the companies in the group were most representative of the Company and had characteristics similar to its own, including stage of product development, a focus on the life sciences industry, and other economic and industry characteristics. Expected Term — The Company uses the simplified method to calculate the expected term, as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term for options granted, and utilized the contractual term for options granted. Risk-Free Interest Rate — The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected life of the stock options. Expected Dividends — To date, the Company has not issued any dividends and does not expect to issue dividends over the life of the options and therefore has estimated the dividend yield to be zero. Subsequent to the closing of the Company’s IPO, the Company determines the fair market value of its common stock using the closing price of its common stock as reported on the Nasdaq Global Select Market. Prior to the closing of the Company’s IPO, there was no public market for the Company’s common stock, and the Company determined the fair value of the shares of its common stock underlying its share-based awards by considering a number of objective and subjective factors, including third-party valuations of the Company’s common stock, the valuation of comparable companies, the Company’s operating and financial performance, and general and industry-specific economic outlook, among other factors. The assumptions underlying these valuations represented management’s best estimate, with the assistance of a third-party valuation specialist, which involved inherent uncertainties and the application of management’s judgment. As a result, if the Company had used different assumptions or estimates, the fair value of the Company’s common stock and its stock-based compensation expense could have been materially different. Compensation expense related to awards is recognized on a straight-line basis by recognizing the grant date fair value over the associated service period of the award, which is generally the vesting term. Management evaluates its award grants and modifications and will adjust the fair value if any are determined to be spring-loaded. The Company accounts for forfeitures as they occur.
Net Loss Per Share	Net Loss Per Share
Income Taxes	Income Taxes Income taxes are recorded in accordance with ASC Topic 740, Income Taxes (ASC 740), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities and for loss and credit carryforwards using enacted tax rates anticipated to be in effect for the year in which the differences are expected to reverse. Valuation allowances are provided if, based on the weight of available evidence, it is more likely than not that some or all the deferred tax assets will not be realized.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of cash and cash equivalents as reported in the statement of cash flows to the balance sheets (in thousands): December 31, 2023 2022 Cash $ 643 $ 2,872 Cash equivalents 48,661 84,829 Total cash and cash equivalents $ 49,304 $ 87,701
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following table sets forth the potential common shares excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive: Year Ended December 31, 2023 2022 Outstanding options 2,540,279 1,365,442 Unvested restricted stock awards 1,007,930 1,199,136 Convertible preferred stock (as converted into common stock) — 20,637,415 Total 3,548,209 23,201,993

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following table presents financial instruments measured at fair value on a recurring basis based on the fair value hierarchy as of December 31, 2023 and 2022 (in thousands): December 31, 2023 2022 Level 1 Assets Cash equivalents Money market funds $ 48,661 $ 84,829
Held-to-Maturity U.S. Treasury Bills	. The following table presents held-to-maturity U.S. Treasury bills information as of each reported date (in thousands): As of December 31, 2023 Balance Sheet Location Original Maturities Amortized Estimated Investments between 3 and 12 months $ 187,263 $ 187,293 Investments, noncurrent greater than 1 year 2,482 2,486 Total $ 189,745 $ 189,779 As of December 31, 2022 Balance Sheet Location Original Maturities Amortized Estimated Investments between 3 and 6 months $ 22,409 $ 22,386

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): December 31, 2023 2022 Research and development expenses $ 7,122 $ 4,846 Compensation and benefits 1,599 665 Professional fees and other 1,160 649 Total $ 9,881 $ 6,160

Capital Stock (Tables)

Capital Stock (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Schedule of Common Stock Authorized	As of December 31, 2023, the Company had reserved authorized shares of common stock for future issuance as follows: December 31, 2023 Shares available for grant under the 2023 Plan 3,206,629 Common stock options outstanding 2,540,279 Shares available for grant under the ESPP 391,271 Total 6,138,179

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Options by Plan	As of December 31, 2023, the Company had the following balances by plan: Options Unvested Shares Available 2023 Plan 1,451,985 — 3,206,629 2020 Plan 1,088,294 1,007,930 — Total 2,540,279 1,007,930 3,206,629
Schedule of Stock Option Activity	The following is a summary of the Company’s stock option activity under its 2023 Plan and 2020 Plan: Shares Weighted-Average Exercise Price Total Intrinsic Value Weighted-Average Remaining Contractual Life (Years) Options outstanding as of December 31, 2021 527,387 $ 0.67 $ 105 9.4 Options granted 838,055 $ 1.18 Options outstanding as of December 31, 2022 1,365,442 $ 0.98 $ 15,561 9.1 Options granted 1,588,235 $ 15.19 Options exercised (268,534) $ 0.73 Options forfeited or expired (144,864) $ 14.85 Options outstanding as of December 31, 2023 2,540,279 $ 9.10 $ 8,291 8.8 Options vested and exercisable as of December 31, 2023 464,934 $ 2.74 $ 3,113 8.2
Schedule of Weighted-Average Assumptions	The following table presents the weighted-average assumptions used in the Black-Scholes option pricing model to determine the fair value of stock options granted during the following periods: Year Ended December 31, 2023 2022 Exercise price $ 15.19 $ 1.18 Expected term (years) 6.01 years 6.07 years Expected stock price volatility 104.6 % 92.2 % Risk-free rate of interest 3.9 % 3.0 % Expected dividend yield — % — %
Schedule of RSA Activity	The following is a summary of the Company’s RSA activity under its 2023 Plan and 2020 Plan: Shares Weighted-Average Grant Date Fair Value Unvested as of December 31, 2021 337,639 $ 0.0108 Granted 977,258 $ 1.7512 Vested (115,761) $ 0.0010 Unvested as of December 31, 2022 1,199,136 $ 1.4290 Vested (191,206) $ 0.3493 Unvested as of December 31, 2023 1,007,930 $ 1.6338
Schedule of Stock-Based Compensation Reported in Statement of Operations	Total stock-based compensation expense reported in the statements of operations was allocated as follows (in thousands): Year Ended December 31, 2023 2022 Research and development $ 2,263 $ 200 General and administrative 2,797 255 Total $ 5,060 $ 455

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets and Liabilities	The components of the Company’s deferred tax assets are as follows (in thousands): December 31, 2023 2022 Net operating loss carryforwards $ 7,890 $ 5,738 Research and development credit carryforwards 5,671 1,357 Capitalized research and development costs 15,037 5,367 Intangible assets 2,048 270 Other 857 183 Total deferred tax assets 31,503 12,915 Valuation allowance (31,503) (12,915) Deferred tax assets, net of valuation allowance $ — $ —
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows for the years ended: December 31, 2023 2022 Statutory federal income tax rate 21.00 % 21.00 % State income taxes, net of federal tax benefits (0.29) 1.69 Research and development credits 5.74 2.81 Permanent items and other (0.60) (0.11) Change in valuation allowance (25.85) (25.39) Total provision for income taxes — % — %
Schedule of Unrecognized Tax Benefits Roll Forward	The following table summarizes the changes to the Company’s unrecognized tax benefits for the years ended December 31, 2023 and 2022 (in thousands): Year Ended December 31, 2023 2022 Beginning balance $ 261 $ 118 Additions related to current year positions 781 143 Additions related to prior year positions 34 — Ending balance $ 1,076 $ 261

Nature of Business (Details)

Nature of Business (Details) $ / shares in Units, $ in Thousands		1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 14, 2023 USD ($) $ / shares shares	Feb. 28, 2023	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares	Feb. 01, 2023 $ / shares
Class of Stock [Line Items]
Gross proceeds of sale of stock			$ 378,800
Reverse stock split conversion ratio		0.926
Common stock par value (in USD per share) | $ / shares			$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Accumulated deficit			$ 124,708	$ 124,708	$ 52,810
Cash, cash equivalents, and investments			$ 239,000	239,000
Net loss				71,898	29,799
Net cash used in operating activities				$ 81,173	$ 29,221
IPO
Class of Stock [Line Items]
Shares issued (in shares) | shares	13,800,000
Price per share (in USD per share) | $ / shares	$ 16
Gross proceeds of sale of stock	$ 201,400
Over-Allotment Option
Class of Stock [Line Items]
Shares issued (in shares) | shares	1,800,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Segment Information (Details)	12 Months Ended
	Dec. 31, 2023 segment
Accounting Policies [Abstract]
Number of operating segments	1

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Restricted Cash	$ 0	$ 0	$ 50,000
Cash	643,000	2,872,000
Cash equivalents	48,661,000	84,829,000
Total cash and cash equivalents	$ 49,304,000	$ 87,701,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Deferred Offering Costs (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Deferred offering costs	$ 0	$ 1.6

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Net Loss per Share (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total (in shares)	3,548,209	23,201,993
Outstanding options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total (in shares)	2,540,279	1,365,442
Unvested restricted stock awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total (in shares)	1,007,930	1,199,136
Convertible preferred stock (as converted into common stock)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total (in shares)	0	20,637,415

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Level 1 | Money market funds
Cash and Cash Equivalents [Line Items]
Cash equivalents	$ 48,661	$ 84,829

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost
Investments	$ 187,263	$ 22,409
Investments, noncurrent	2,482	0
Total	189,745	22,409
Estimated Fair Value
Investments	187,293
Investments, noncurrent	2,486
Total	$ 189,779	$ 22,386

Commitment and Contingencies (D

Commitment and Contingencies (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Jul. 31, 2020
Other Commitments [Line Items]
Research and development			$ 70,361	$ 26,250
Mitsubishi Tanabe | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Other Commitments [Line Items]
Upfront fee					$ 1,000
Development milestone payments					9,000
First commercial milestone payments					155,000
Second commercial milestone payment					$ 10,000
Expiration period					10 years
Non-compete period					3 years
Research and development			$ 9,000	$ 0
Proceeds received from milestones achieved	$ 5,000	$ 4,000
Mitsubishi Tanabe | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum
Other Commitments [Line Items]
Royalties percentage					10%
Termination period					180 days
Mitsubishi Tanabe | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Minimum
Other Commitments [Line Items]
Termination period					90 days

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Research and development expenses	$ 7,122	$ 4,846
Compensation and benefits	1,599	665
Professional fees and other	1,160	649
Accrued liabilities	$ 9,881	$ 6,160

Capital Stock - Schedule of Com

Capital Stock - Schedule of Common Stock (Details)	Dec. 31, 2023 shares
Class of Stock [Line Items]
Common stock shares reserved for future issuance (in shares)	6,138,179
Stock Options
Class of Stock [Line Items]
Common stock shares reserved for future issuance (in shares)	2,540,279
Employee Stock
Class of Stock [Line Items]
Common stock shares reserved for future issuance (in shares)	391,271
2023 Plan
Class of Stock [Line Items]
Common stock shares reserved for future issuance (in shares)	3,206,629

Capital Stock - Narrative (Deta

Capital Stock - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended			3 Months Ended	11 Months Ended	12 Months Ended
	Feb. 07, 2024	Feb. 14, 2023	Jun. 30, 2022	Jan. 31, 2022	Feb. 28, 2021	Apr. 30, 2021	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Feb. 28, 2023
Class of Stock [Line Items]
Common stock shares authorized (in shares)							500,000,000	500,000,000	319,000,000	500,000,000
Convertible preferred stock, shares authorized (in shares)										50,000,000
Gross proceeds of sale of stock							$ 378,800
Common Stock
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)								20,637,415
Subsequent Event
Class of Stock [Line Items]
Sale of warrants (in shares)	549,755
Price per share of warrants sold (in USD per share)	$ 13.499
Series A Convertible Preferred Stock
Class of Stock [Line Items]
Convertible preferred stock, shares authorized (in shares)							0	0	86,332,216
Conversion of preferred stock to common stock upon closing initial public offering (in shares)								86,332,216
Purchase price temporary equity (in USD per share)				$ 0.477		$ 0.477
Issuance of Series A convertible preferred stock (in shares)				25,151,957	10,868,432
Issuance of convertible preferred stock, net of issuance costs				$ 12,000		$ 23,800			$ 11,991
Issuance of convertible preferred stock, net of issuance costs (in shares)						50,311,827			25,151,957
Series B Convertible Preferred Stock
Class of Stock [Line Items]
Convertible preferred stock, shares authorized (in shares)							0	0	136,510,868
Conversion of preferred stock to common stock upon closing initial public offering (in shares)								136,510,868
Purchase price temporary equity (in USD per share)			$ 0.8644
Issuance of convertible preferred stock, net of issuance costs			$ 117,700						$ 117,657
Issuance of convertible preferred stock, net of issuance costs (in shares)			136,510,868						136,510,868
IPO
Class of Stock [Line Items]
Price per share (in USD per share)		$ 16
Shares issued (in shares)		13,800,000
Gross proceeds of sale of stock		$ 201,400
IPO | Common Stock
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)		20,637,415
IPO | Series A Convertible Preferred Stock
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)		86,332,216
IPO | Series B Convertible Preferred Stock
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon closing initial public offering (in shares)		136,510,868
Private Placement | Subsequent Event
Class of Stock [Line Items]
Price per share (in USD per share)	$ 13.50
Shares issued (in shares)	8,339,169
Gross proceeds of sale of stock	$ 120,000

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended	12 Months Ended
	Feb. 14, 2024	Jul. 01, 2023	Jul. 07, 2020	Feb. 28, 2023	Dec. 31, 2023	Dec. 31, 2022	Feb. 07, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized share-based compensation expense					$ 15.2
Fair value of options outstanding					1.5	$ 0.1
Aggregate intrinsic value of options outstanding					$ 3.2	$ 0
Shares available for grant (in shares)					3,206,629
Granted (in USD per share)					$ 12.41	$ 2.12
Options granted (in shares)					1,588,235	838,055
Options granted (in usd per share)					$ 15.19	$ 1.18
Subsequent Event
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Exercise price (in USD per share)							$ 0.001
Options granted (in shares)	1,469,600
Options granted (in usd per share)	$ 14.25
Tranche 1 | Subsequent Event
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Ownership limitation percentage							4.99%
Tranche 2 | Subsequent Event
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Ownership limitation percentage							9.99%
Tranche 3 | Subsequent Event
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Ownership limitation percentage							19.99%
2020 Equity Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Grants expiration period			10 years
Grants vesting period			4 years
Shares available for grant (in shares)					0
Shares available for grant under the 2023 Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized (in shares)				4,650,000
Percent of outstanding shares				4%
Number of additional shares allowed under the plan (in shares)				100,000,000
Shares available for grant (in shares)					3,206,629
Unvested restricted stock awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized share-based compensation expense, period of recognition (in years)					1 year 3 months 18 days
Unrecognized share-based compensation expense related to RSAs					$ 1
Aggregate fair value vested					$ 0.1	$ 0.1
Employee Stock | Shares available for grant under the ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized (in shares)				400,000
Percent of outstanding shares				1%
Number of additional shares allowed under the plan (in shares)				15,000,000
Purchase price of common stock, percentage		85%
Offering period				6 months
Shares available for grant (in shares)					391,271
Cumulative shares issued (in shares)					(8,729)
Outstanding options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized share-based compensation expense, period of recognition (in years)					1 year 6 months

Stock-Based Compensation - Opti

Stock-Based Compensation - Options by Plan (Details) - shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding options (in shares)	2,540,279	1,365,442	527,387
Shares available for grant (in shares)	3,206,629
Unvested restricted stock awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
RSAs issued (in shares)	1,007,930
2023 Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding options (in shares)	1,451,985
Shares available for grant (in shares)	3,206,629
2023 Plan | Unvested restricted stock awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
RSAs issued (in shares)	0
2020 Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding options (in shares)	1,088,294
Shares available for grant (in shares)	0
2020 Plan | Unvested restricted stock awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
RSAs issued (in shares)	1,007,930

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Shares
Beginning balance (in shares)	1,365,442	527,387
Options granted (in shares)	1,588,235	838,055
Options exercised (in shares)	(268,534)
Options forfeited (in shares)	(144,864)
Ending balance (in shares)	2,540,279	1,365,442	527,387
Options vested and exercisable (in shares)	464,934
Weighted-Average Exercise Price
Beginning balance (in usd per share)	$ 0.98	$ 0.67
Options granted (in usd per share)	15.19	1.18
Options exercised (in usd per share)	0.73
Options forfeited (in usd per share)	14.85
Ending balance (in usd per share)	9.10	$ 0.98	$ 0.67
Options granted and exercisable (in usd per share)	$ 2.74
Total Intrinsic Value (in thousands)
Options outstanding	$ 8,291	$ 15,561	$ 105
Exercisable	$ 3,113
Weighted-Average Remaining Contractual Life (Years)
Options outstanding	8 years 9 months 18 days	9 years 1 month 6 days	9 years 4 months 24 days
Vested and exercisable	8 years 2 months 12 days

Stock-Based Compensation - Valu

Stock-Based Compensation - Valuation Assumptions (Details) - Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Exercise price (in USD per share)	$ 15.19	$ 1.18
Expected term (years)	6 years 3 days	6 years 25 days
Expected stock price volatility	104.60%	92.20%
Risk-free rate of interest	3.90%	3%
Expected dividend yield	0%	0%

Stock-Based Compensation - RSA

Stock-Based Compensation - RSA Activity (Details) - Unvested restricted stock awards - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Shares
Unvested, beginning balance (in shares)	1,199,136	337,639
Granted (in shares)		977,258
Vested (in shares)	(191,206)	(115,761)
Unvested, ending balance (in shares)	1,007,930	1,199,136
Weighted-Average Grant Date Fair Value
Unvested, beginning balance (in USD per share)	$ 1.4290	$ 0.0108
Granted (in USD per share)		1.7512
Vested (in USD oer share)	0.3493	0.0010
Unvested, ending balance (in USD per share)	$ 1.6338	$ 1.4290

Stock-Based Compensation - Repo

Stock-Based Compensation - Reported in Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total	$ 5,060	$ 455
Research and development
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total	2,263	200
General and administrative
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total	$ 2,797	$ 255

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 7,890	$ 5,738
Research and development credit carryforwards	5,671	1,357
Capitalized research and development costs	15,037	5,367
Intangible assets	2,048	270
Other	857	183
Total deferred tax assets	31,503	12,915
Valuation allowance	(31,503)	(12,915)
Deferred tax assets, net of valuation allowance	$ 0	$ 0

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Current income tax expense (benefit)	$ 0	$ 0
Deferred income tax expense (benefit)	0	0
Increase (decrease) in valuation allowance	18,600,000	7,600,000
Federal NOL carryforwards	35,000,000	25,700,000
State NOL carryforwards	8,600,000	5,300,000
Research and development tax credit carryforwards	5,671,000	1,357,000
Unrecognized tax benefits	1,076,000	261,000	$ 118,000
Increase related to current year positions	781,000	143,000
Accrued interest or penalties related to uncertain tax positions	$ 0	$ 0

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	21%	21%
State income taxes, net of federal tax benefits	(0.29%)	1.69%
Research and development credits	5.74%	2.81%
Permanent items and other	(0.60%)	(0.11%)
Change in valuation allowance	(25.85%)	(25.39%)
Total provision for income taxes	0%	0%

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 261	$ 118
Additions related to current year positions	781	143
Additions related to prior year positions	34	0
Ending balance	$ 1,076	$ 261