Longboard Pharmaceuticals (LBPH) 10-Q 2 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 30, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Entity Registrant Name	Longboard Pharmaceuticals, Inc.
Entity Central Index Key	0001832168
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity File Number	001-40192
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-5009619
Entity Address, Address Line One	4275 Executive Square
Entity Address, Address Line Two	Suite 950
Entity Address, City or Town	La Jolla
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92037
City Area Code	858
Local Phone Number	789-9283
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Trading Symbol	LBPH
Title of 12(b) Security	Common stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Common Stock, Shares Outstanding		38,880,054
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Document Quarterly Report	true
Document Transition Report	false

Condensed Balance Sheets (unaud

Condensed Balance Sheets (unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 54,395	$ 14,331
Short-term Investments	266,648	34,167
Prepaid expenses and other current assets	2,398	1,723
Total current assets	323,441	50,221
Right-of-use assets	3,977	472
Property and equipment	3	4
Other long-term assets	244	0
Total assets	327,665	50,697
Current liabilities:
Accounts payable	1,045	1,001
Accrued research and development expenses	7,304	4,556
Accrued compensation and related expenses	1,054	3,374
Accrued other expenses	572	368
Right-of-use liabilities, current portion	315	475
Total current liabilities	10,290	9,774
Right-of-use liabilities, net of current portion	3,667	0
Commitments and contingencies (see Note 9)
Stockholders' equity:
Preferred Stock, Value, Issued	0	0
Common Stock, Value, Issued	3	2
Additional paid-in-capital	469,621	181,563
Accumulated other comprehensive loss	(366)	(78)
Accumulated deficit	(155,550)	(140,564)
Total stockholders' equity	313,708	40,923
Total liabilities and stockholders' equity	327,665	50,697
Non-Voting Common Stock [Member]
Stockholders' equity:
Common Stock, Value, Issued

Condensed Balance Sheets (una_2

Condensed Balance Sheets (unaudited) (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	33,607,490	22,096,494
Common stock, shares outstanding	33,607,490	22,096,494
Non-Voting Common Stock [Member]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	5,270,755	2,420,755
Common stock, shares outstanding	5,270,755	2,420,755

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating expenses:
Research and development	$ 13,170	$ 8,530
General and administrative	4,940	3,432
Total operating expenses	18,110	11,962
Loss from operations	(18,110)	(11,962)
Interest income, net	3,133	516
Other expense	(9)	(10)
Net loss	$ (14,986)	$ (11,456)
Net loss per share, basic	$ (0.42)	$ (0.56)
Net loss per share, diluted	$ (0.42)	$ (0.56)
Weighted-average shares outstanding, basic	35,321,794	20,409,794
Weighted-average shares outstanding, diluted	35,321,794	20,409,794
Comprehensive loss:
Net loss	$ (14,986)	$ (11,456)
Unrealized gain (loss) on short-term investments	(288)	271
Comprehensive loss	$ (15,274)	$ (11,185)

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net loss	$ (14,986)	$ (11,456)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	1,749	697
Depreciation	1	1
Accretion of premiums on investments, net	(1,849)	(1)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(770)	(798)
Accounts payable	43	(1,027)
Accrued research and development expenses	2,748	645
Accrued compensation and related expenses	(2,320)	(1,734)
Accrued other expenses	205	578
Operating right-of-use assets and lease liabilities, net	2	(2)
Net cash used in operating activities	(15,177)	(13,097)
Cash flows from investing activities:
Purchases of short-term investments	(255,119)	(20,567)
Maturities of short-term investments	24,200	26,650
Net cash provided by (used in) investing activities	(230,919)	6,083
Cash flows from financing activities:
Proceeds from issuance of common stock	301,350	23,000
Payments for offering costs	(14,994)	(1,640)
Proceeds from exercise of stock options	48	0
Net cash provided by financing activities	286,404	21,360
Net increase in cash, cash equivalents and restricted cash	40,308	14,346
Cash and cash equivalents at the beginning of the period	14,331	10,775
Cash and cash equivalents at the end of the period	54,639	25,121
Supplemental disclosure of cash flow information:
Offering costs in accounts payable and accrued other expenses	$ 3	$ 172

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Organization and Basis of Presentation	Note 1. Organization and Basis of Presentation Description of Business Longboard Pharmaceuticals, Inc. (the Company), formerly Arena Neuroscience, Inc., was incorporated in the state of Delaware on January 3, 2020, and is based in La Jolla, California. The Company was organized and initially wholly owned by Arena Pharmaceuticals, Inc. (Arena), until the closing of its Series A convertible preferred stock (Series A Preferred Stock) financing in October 2020. The Company is a clinical-stage biopharmaceutical company focused on developing novel, transformative medicines for neurological diseases. The Company’s most advanced product candidate, bexicaserin (LP352), is a serotonin receptor that is being developed for the treatment of seizures associated with developmental and epileptic encephalopathies and is currently in the planning stages of a global Phase 3 program. The Company is also developing LP659, an S1P receptor modulator, which could have applicability in multiple rare neuroinflammatory conditions. Basis of Presentation The Company’s unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and applicable regulations of the U.S. Securities and Exchange Commission (SEC). Accordingly, the accompanying unaudited condensed financial statements do not include all of the information and notes required by GAAP for complete financial statements. The unaudited condensed financial statements reflect all adjustments which, in the opinion of management, are necessary for a fair statement of the results for the periods presented. All such adjustments are of a normal and recurring nature. The balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all information and notes required by GAAP for complete financial statements. The operating results presented in these unaudited condensed financial statements are not necessarily indicative of the results that may be expected for any future periods. The Company’s unaudited condensed financial statements should be read in conjunction with the audited financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed on March 12, 2024. Liquidity and Capital Resources Since its inception, the Company has devoted substantially all of its resources to research and development (R&D) activities, organizing and staffing, business planning, raising capital, in-licensing intellectual property rights and establishing its intellectual property portfolio, and providing general and administrative (G&A) support for these operations, and has funded its operations primarily with the net proceeds from the issuance of Series A Preferred Stock and common stock. The Company has incurred losses and negative cash flows from operations since commencement of its operations. The Company had an accumulated deficit of $ 155.6 million and $ 140.6 million as of March 31, 2024 and December 31, 2023, respectively. Management expects the Company will incur substantial operating losses for the foreseeable future in order to complete preclinical studies and clinical trials, seek regulatory approval, and launch and commercialize any product candidates for which it receives regulatory approval. The Company will need to raise additional capital through public or private equity or debt financings or other capital sources, including potential collaborations, licenses and other similar arrangements. As of March 31, 2024, the Company had available cash, cash equivalents and short-term investments of $ 321.0 million and working capital of $ 313.2 million to fund future operations. Management believes that its capital resources as of March 31, 2024 will be sufficient to fund the Company’s operations for at least 12 months after the date these unaudited condensed financial statements are issued.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Use of Estimates The Company’s financial statements are prepared in accordance with GAAP. The preparation of the Company’s financial statements requires the Company to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Such estimates include the accrual of R&D expenses and stock-based compensation. Management evaluates its estimates on an ongoing basis. Estimates are based on the Company’s historical experience, knowledge of current events and actions it may undertake in the future, and actual results may materially differ from these estimates and assumptions. Concentration of Credit Risk Financial instruments which potentially subject the Company to significant concentration of credit risk consist of cash, cash equivalents and short-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits and invests in short-term investments with the primary objectives of seeking to preserve principal, achieve liquidity requirements and safeguard funds. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held and the nature, including the credit-ratings, of its short-term investments, but we have not eliminated all credit risk. Comprehensive Loss Comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on short-term investments. Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market funds, corporate debt securities, and obligations of U.S. government-sponsored enterprises. The carrying amounts reported in the unaudited condensed balance sheets for cash and cash equivalents are valued at cost, which approximates fair value. The following table provides a reconciliation of the components of cash, cash equivalents and restricted cash reported in the condensed balance sheets to the total of the amount presented in the condensed statements of cash flows: March 31, December 31, (in thousands) 2024 2023 Cash and cash equivalents $ 54,395 $ 14,331 Restricted cash included in other long-term assets 244 — Total cash, cash equivalents and restricted cash presented in the condensed statements of cash flows $ 54,639 $ 14,331 The restricted cash relates to deposits for the Company’s office lease. The deposit will be reduced to $ 90,000 on January 1, 2027 as long as there are no defaults under the lease, and the remaining restriction will lapse when the lease expires on December 31, 2030. Short-Term Investments Short-term investments primarily consist of commercial paper, corporate debt securities, and government and agency bonds. The Company has classified these investments as available-for-sale securities, as the sale of such investments may be required prior to maturity to implement management strategies, and therefore has classified all investments with maturity dates beyond three months at the date of purchase as current assets in the accompanying unaudited balance sheets. Any premium or discount arising at purchase is amortized and/or accreted to interest income as an adjustment to yield using the straight-line method over the life of the instrument. Investments are reported at their estimated fair value. Unrealized gains and losses are included in accumulated other comprehensive loss as a component of stockholders' equity until realized. R&D Expenses R&D expenses are expensed in the periods in which they are incurred. External expenses consist primarily of payments to contract research organizations, outside consultants and other third parties in connection with the Company’s research, preclinical and clinical activities, process development, manufacturing activities, regulatory and other services. Certain R&D external expenses are recognized based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its service providers or the estimate of the level of service that has been performed at each reporting date. R&D expenses amounted to $ 13.2 million and $ 8.5 million for the three months ended March 31, 2024 and 2023, respectively. Stock-Based Compensation Stock-based awards are measured at fair value and compensation expense is recognized over the requisite service period. Forfeitures are accounted for in the period they occur. The Company determines the fair value of each stock-based award on the date of grant using the Black-Scholes option pricing model which requires the input of subjective assumptions, including price volatility of the underlying stock, risk-free interest rate, dividend yield, and expected term of the option. Leases The Company determines if an arrangement is a lease or contains lease components at inception. Lease terms are determined at the commencement date by considering whether renewal options and termination options, if any, are reasonably assured of exercise. For long-term operating leases, the Company recognizes a lease liability and a right-of-use (ROU) asset on its balance sheets and recognizes lease expense on a straight-line basis over the lease term. The lease liability is determined as the present value of future lease payments using the discount rate implicit in the lease or, if the implicit rate is not readily determinable, an estimate of the Company’s incremental borrowing rate. The ROU asset is based on the lease liability, adjusted for any prepaid or deferred rent. The Company only has operating leases and does not have any financing leases. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Since the Company had a net loss in each of the periods presented, basic and diluted net loss per share of common stock are the same. The table below provides potentially dilutive securities not included in the calculation of the diluted net loss per share as it would be anti-dilutive: Three Months Ended March 31, 2024 2023 Options to purchase common stock 5,537,267 3,877,556 Restricted stock awards, issued but unvested 150,660 — Total 5,687,927 3,877,556 Recent Accounting Pronouncements The Company does not believe that any recently issued, but not effective, accounting standards, if currently adopted, would have a material effect on our condensed financial statements.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 3. Fair Value Measurements The accounting guidance defines fair value, establishes a consistent framework for measuring fair value, and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1 — Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Level 2 — Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. Level 3 — Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The following table summarizes the Company's financial instruments measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023. Fair Value Measurements at (in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of March 31, 2024 Assets: Money market funds $ 46,086 $ 46,086 $ — $ — Commercial paper $ 53,749 $ — $ 53,749 $ — Corporate debt securities 57,045 — 57,045 — Government and agency securities 160,843 150,812 10,031 — Total assets measured at fair value $ 317,723 $ 196,898 $ 120,825 $ — As of December 31, 2023 Assets: Money market funds $ 11,196 $ 11,196 $ — $ — Commercial paper $ 16,806 $ — $ 16,806 $ — Corporate debt securities 4,256 — 4,256 — Government and agency securities 13,105 13,105 — — Total assets measured at fair value $ 45,363 $ 24,301 $ 21,062 $ —

Short-Term Investments

Short-Term Investments	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents [Abstract]
Short-Term Investments	Note 4. Short-Term Investments The following table summarizes short-term investments: As of March 31, 2024 Unrealized (in thousands) Amortized Cost Gains Losses Estimated Fair Value Commercial paper $ 50,863 $ — $ ( 104 ) $ 50,759 Corporate debt securities 57,260 — ( 215 ) 57,045 Government and agency securities 158,889 1 ( 46 ) 158,844 Total short-term investments $ 267,012 $ 1 $ ( 365 ) $ 266,648 As of December 31, 2023 Unrealized (in thousands) Amortized Cost Gains Losses Estimated Fair Value Commercial paper $ 16,813 $ — $ ( 7 ) $ 16,806 Corporate debt securities 4,277 — ( 21 ) 4,256 Government and agency securities 13,155 2 ( 52 ) 13,105 Total short-term investments $ 34,245 $ 2 $ ( 80 ) $ 34,167 The following table summarizes the maturities of the Company's short-term investments at March 31, 2024: (in thousands) Amortized Cost Estimated Fair Value Due in one year or less $ 232,745 $ 232,489 Due in one to two years 34,267 34,159 Total short-term investments $ 267,012 $ 266,648 The following table shows the Company’s available-for-sale investments’ gross unrealized losses and fair value aggregated by investment category and length of time that individual securities have been in a continuous loss position, at March 31, 2024 and December 31, 2023: As of March 31, 2024 Less than 12 months More than 12 months Total (in thousands) Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Commercial paper 15 $ 50,759 $ ( 104 ) — $ — $ — 15 $ 50,759 $ ( 104 ) Corporate debt securities 19 57,045 ( 215 ) — — — 19 57,045 ( 215 ) Government and agency securities 11 134,079 ( 32 ) 2 3,189 ( 14 ) 13 137,268 ( 46 ) 45 $ 241,883 $ ( 351 ) 2 $ 3,189 $ ( 14 ) 47 $ 245,072 $ ( 365 ) As of December 31, 2023 Less than 12 months More than 12 months Total (in thousands) Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Commercial paper 8 $ 16,806 $ ( 7 ) — $ — $ — 8 $ 16,806 $ ( 7 ) Corporate debt securities — — — 3 4,256 ( 21 ) 3 4,256 ( 21 ) Government and agency securities — — — 2 3,149 ( 52 ) 2 3,149 ( 52 ) 8 $ 16,806 $ ( 7 ) 5 $ 7,405 $ ( 73 ) 13 $ 24,211 $ ( 80 ) The Company reviews its investments to identify and evaluate investments that have an indication of possible other-than-temporary impairment. Factors considered in determining whether a loss is other-than-temporary include the length of time and extent to which fair value has been less than the cost basis, any changes to the underlying credit risk of the investment, and the Company’s intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in market value. The unrealized losses in the Company’s investments were caused by changes in interest rates caused by changing economic conditions, and not from a decline in credit of their underlying issuers. The Company does not generally intend to sell these investments and it is not more likely than not that the Company will be required to sell these investments before recovery of their amortized cost basis which may be at maturity. As such, the Company has classified these losses as temporary in nature.

Accrued Other Expenses

Accrued Other Expenses	3 Months Ended
	Mar. 31, 2024
Accrued Liabilities, Current [Abstract]
Accrued Other Expenses	Note 5. Accrued Other Expenses Accrued other expenses consisted of t he following: As of (in thousands) March 31, 2024 December 31, 2023 Accrued legal and accounting fees $ 257 $ 40 Accrued consulting fees 177 218 Accrued taxes 50 40 Accrued travel expenses 27 43 Accrued computer related expenses 11 15 Accrued other 50 12 Total $ 572 $ 368

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Stockholders' Equity	Note 6. Stockholders’ Equity Private Placement In March 2024, the Company entered into a Non-Voting Common Stock Purchase Agreement (the “Agreement”) with an investment fund (the “Investor”) affiliated with Farallon Capital Management, L.L.C. (“Farallon”), pursuant to which the Company sold and issued 2,850,000 shares of its non-voting common stock to the Investor at a purchase price of $ 21.00 per share, for aggregate gross proceeds of $ 59.9 million, in a private placement transaction. Funds affiliated with Farallon have been and continue to be a greater than 5% stockholder in the Company. No discounts, commissions or placement agent fees were payable in connection with the foregoing private placement. Follow-On Public Offerings In January 2024, the Company raised $ 241.5 million in a follow-on public offering. The Company issued and sold 11,500,000 shares of common stock which included 1,500,000 shares of common stock sold pursuant to the full exercise by the underwriters of their option to purchase additional shares, at a public offering price of $ 21.00 per share. The Company raised $ 226.5 million in net proceeds from the follow-on public offering after deducting underwriters' commissions of $ 14.5 million and other expenses of $ 0.5 million. In February 2023, the Company raised $ 23.0 million in a follow-on public offering. The Company issued and sold 5,750,000 shares of common stock which included 750,000 shares of common stock issued pursuant to the over-allotment option granted to the underwriters to purchase additional shares of common stock, at a public offering price of $ 4.00 per share. The Company raised $ 21.2 million in net proceeds from the follow-on public offering after deducting underwriters' commissions of $ 1.4 million and issuance costs of $ 0.4 million. Sales Agreement In September 2022, the Company entered into a Controlled Equity Offering SM Sales Agreement (the Sales Agreement) with Cantor Fitzgerald & Co., as sales agent (Cantor Fitzgerald), pursuant to which it may issue and sell its common stock from time to time through an “at the market offering” (ATM) program under the Sales Agreement. The Company has no obligation to sell any shares of common stock under the Sales Agreement and may at any time suspend sales under the Sales Agreement. Cantor Fitzgerald will be entitled to compensation in an amount of 3% of the gross proceeds of any shares of common stock sold under the Sales Agreement. In August 2023, the Company filed a prospectus supplement providing for the sale of up to $ 75.0 million of shares of common stock under the Sales Agreement. The Company sold 1,422,250 shares of its common stock for gross proceeds of $ 8.8 million during 2023. In March 2024, the Company filed a sales agreement prospectus providing for the sale of up to $ 150.0 million of shares of common stock under the Sales Agreement (exclusive of shares sold previously). A s of March 31, 2024, no shares of common stock had been sold pursuant to the most recent sales agreement prospectus. Amended and Restated Certificate of Incorporation In March 2021, the Company amended and restated the Company’s certificate of incorporation to, among other things, increase the authorized shares of voting common stock, non-voting common stock and preferred stock to 300,000,000 shares, 10,000,000 shares and 10,000,000 shares, respectively. Voting Common Stock and Non-Voting Common Stock As of March 31, 2024, the Company had 33,607,490 shares of voting common stock outstanding and 5,270,755 shares of non-voting common stock outstanding. As of December 31, 2023, the Company had 22,096,494 shares of voting common stock outstanding and 2,420,755 shares of non-voting common stock outstanding. Reconciliation of Changes in Stockholders’ Equity The following tables document the changes in stockholders' equity for the three months ended March 31, 2024 and 2023 (unaudited): Voting Common Stock Non-Voting Common Stock (in thousands, except shares) Number of Shares Amount Number of Shares Amount Additional Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity Balance at December 31, 2023 22,096,494 $ 2 2,420,755 $ — $ 181,563 $ ( 78 ) $ ( 140,564 ) $ 40,923 Issuance of common stock in follow-on public offering 11,500,000 1 — — 241,499 — — 241,500 Issuance of non-voting common stock in PIPE financing — — 2,850,000 — 59,850 — — 59,850 Financing related fees — — — — ( 15,088 ) — — ( 15,088 ) Stock-based compensation — — — — 1,749 — — 1,749 Stock option exercises 10,996 — — — 48 — — 48 Unrealized loss on short-term investments, net — — — — — ( 288 ) — ( 288 ) Net loss — — — — — — ( 14,986 ) ( 14,986 ) Balance at March 31, 2024 33,607,490 $ 3 5,270,755 $ — $ 469,621 $ ( 366 ) $ ( 155,550 ) $ 313,708 Voting Common Stock Non-Voting Common Stock (in thousands, except shares) Number of Shares Amount Number of Shares Amount Additional Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity Balance at December 31, 2022 13,585,950 $ 1 3,629,400 $ — $ 148,303 $ ( 692 ) $ ( 86,142 ) $ 61,470 Issuance of common stock in follow-on public offering 5,750,000 1 — — 21,187 — — 21,188 Conversion of non-voting common stock to voting common stock 1,208,645 ( 1,208,645 ) — — Financing related fees ( 37 ) ( 37 ) Stock-based compensation — — — — 697 — — 697 Unrealized gain on short-term investments, net — — — — — 271 — 271 Net loss — — — — — — ( 11,456 ) ( 11,456 ) Balance at March 31, 2023 20,544,595 $ 2 2,420,755 $ — $ 170,150 $ ( 421 ) $ ( 97,598 ) $ 72,133

License Agreement with Arena Ph

License Agreement with Arena Pharmaceuticals, Inc.	3 Months Ended
	Mar. 31, 2024
Related Party Transactions [Abstract]
License Agreement with Arena Pharmaceuticals, Inc.	Note 7. License Agreement with Arena Pharmaceuticals, Inc. The Company entered into a license agreement (Arena License Agreement), a services agreement, and a royalty purchase agreement in October 2020 with Arena. Arena was purchased by Pfizer in March 2022. The following section summarizes the Arena License Agreement. Arena License Agreement Pursuant to the Arena License Agreement, the Company has obtained an exclusive, royalty bearing, sublicensable, worldwide license under certain know-how and patents of Arena to develop and commercialize bexicaserin (LP352) for any use in humans, LP659 for the treatment of developmental, degenerative and autoimmune disease, disorders or conditions of the CNS or peripheral nervous system in humans, and certain other compounds for the treatment of CNS indication in humans (pharmaceutical products containing any such compounds, Licensed Products). Arena has a right of first negotiation to acquire certain development and commercial rights to LP659 products. As consideration for the rights granted to the Company under the Arena License Agreement, the Company will be required to pay to Arena a mid-single digit royalty on net sales of Licensed Products of LP352, and a low single digit royalty on net sales of all other Licensed Products, by the Company, its affiliates or its sublicensees, subject to standard reductions. The Company’s royalty obligations continue on a Licensed Product-by-Licensed Product and country-by-country basis until the later of the (i) tenth anniversary of the first commercial sale of such product in such country or (ii) expiration of the last-to-expire valid claim of the patents licensed by the Company under the Arena License Agreement covering the manufacture, use or sale of such product in such country.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Note 8. Stock-Based Compensation Equity Incentive Plan In October 2020, the Company’s board of directors and stockholders approved the 2020 Equity Incentive Plan (2020 Plan), which provided for the grant of incentive stock options, nonstatutory stock options, restricted stock awards, restricted stock unit awards, and stock appreciation rights to its employees, members of its board of directors, and consultants. The Company’s board of directors determined the exercise price, vesting and expiration period of the grants under the 2020 Plan. The Company's board of directors adopted the 2021 Equity Incentive Plan (2021 Plan) in February 2021 and the Company's stockholders approved the 2021 Plan in March 2021. The 2021 Plan became effective on March 11, 2021. The 2021 Plan is the successor and continuation of the 2020 Plan. No additional awards may be granted under the 2020 Plan and all outstanding awards under the 2020 Plan remain subject to the terms of the 2020 Plan. In October 2023, the compensation committee of the Company’s board of directors amended the 2021 Plan to incorporate an additional pool of 1,000,000 shares that the Company is authorized to issue to individuals who satisfy the standards for inducement grants under Nasdaq Marketplace Rule 5635(c)(4) and the related guidance under Nasdaq IM 5635-1, including individuals who were not previously an employee or director of the Company or are following a bona fide period of non-employment, in each case as an inducement material to such individual entering into employment with the Company. As of March 31, 2024, the 2021 Plan authorizes and provides for the issuance of up to 6,640,983 shares of comm on stock, which consists of 5,537,267 shares of common stock subject to outstanding options, 150,660 shares of common stock subject to outstanding restricted stock units and 953,056 shares of common stock available for grant. The number of shares of common stock reserved for issuance under the 2021 Plan automatically increases on January 1 of each calendar year, through January 1, 2031, in an amount equal to (i) 5% of the total number of shares of common stock outstanding on December 31 of the fiscal year before the date of each automatic increase (determined on an as-converted to voting common stock basis, without regard to any limitations on the conversion of the non-voting common stock), or (ii) a lesser number of shares determined by the Company’s board of directors prior to the applicable January 1. Recipients of stock options are eligible to purchase shares of the Company’s common stock at an exercise price equal to no less than the estimated fair market value of such stock on the date of grant. The maximum term of options granted under the 2020 and 2021 Plans (or collectively, the Equity Plans) is ten years and, in general, the options issued under the Equity Plans vest over a one to four year period from the vesting commencement date. Stock Award Grants under the Equity Plans A summary of the Company’s stock option activity is as follows: Number of Options Outstanding Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (in Years) Aggregate Intrinsic Value Balance at December 31, 2023 3,856,819 $ 5.10 8.3 $ 5,678 Options granted 1,708,014 19.92 Options exercised ( 10,996 ) 4.40 Options forfeited/cancelled ( 16,570 ) 8.95 Balance at March 31, 2024 5,537,267 $ 9.66 8.6 $ 66,208 Vested and expected to vest at March 31, 2024 5,537,267 $ 9.66 8.6 $ 66,208 Options exercisable at March 31, 2024 2,018,876 $ 5.47 7.6 $ 32,573 Options exercisable at March 31, 2024 included 1,917,244 vested stock options and 101,632 stock options that are subject to an early exercise provision. The following table presents the weighted-average assumptions used for the stock option grants for the three months ended March 31, 2024 and 2023, along with the related grant date fair value: Three Months Ended March 31, 2024 2023 Stock price $ 19.92 $ 4.37 Risk-free interest rate 4.14 % 3.83 % Dividend yield 0.00 % 0.00 % Expected volatility 83.36 % 77.55 % Expected life (years) 6.0 6.0 Estimated grant date fair value per share of award granted $ 14.55 $ 3.05 Determination of Fair Value of Common Stock. The Company utilizes the closing stock price of the common stock on the Nasdaq Global Market as both the exercise price and an input to the Black Scholes option pricing model to determine stock-based compensation expense. Risk-free interest rate . The risk-free interest rate is based on the U.S. Treasury yield in effect at the time of grant for zero coupon U.S. Treasury notes with maturities similar to the expected term of the awards. Expected dividend yield . The Company bases the expected dividend yield assumption on the fact that it has never paid cash dividends and has no present intention to pay cash dividends and, therefore, used an expected dividend yield of zero. Expected volatility . Since the Company is a newly public company and does not have a trading history for its common stock, the expected volatility assumption is based on volatilities of a peer group of similar companies whose share prices are publicly available. The peer group was developed based on companies in the biotechnology industry. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available. Expected life . The expected life represents the period of time that options are expected to be outstanding. Because the Company does not have historical exercise behavior, it determines the expected life assumption using the simplified method, for employees, which is an average of the contractual term of the option and its vesting period. The expected term for nonemployee options is equal to the contractual term. A summary of the Company’s restricted stock unit (RSU) activity is as follows: Number of RSUs Outstanding Weighted-Average Grant Date Fair Value Balance at December 31, 2023 — $ — RSUs granted 151,500 19.32 RSUs vested — — RSUs forfeited/cancelled ( 840 ) 19.32 Balance at March 31, 2024 150,660 $ 19.32 RSUs vest annually over four years from the grant date. Stock-Based Compensation Expense Stock-based compensation expense recognized for all equity awards has been reported in the statements of operations and comprehensive loss as follows: Three Months Ended March 31, (in thousands) 2024 2023 Research and development $ 820 $ 339 General and administrative 929 358 Total $ 1,749 $ 697 Total stock-based compensation expense for the three months ended March 31, 2024 and 2023 included $ 0.1 million and $ 0 of expense, respectively, related to the vesting of RSUs. As of March 31, 2024, unrecognized stock-based compensation expense related to outstanding unvested stock option awards and outstanding unvested RSUs was $ 30.0 million and $ 2.8 million, respectively, which is expected to be recognized over a remaining weighted-average period of approximatel y 3.0 y ears and 3.9 years, respectively. Employee Stock Purchase Plan The Company's board of directors adopted the 2021 Employee Stock Purchase Plan (ESPP) in February 2021, the Company's stockholders approved the ESPP in March 2021 and it became effective on March 11, 2021. As of March 31, 2024, the ESPP authorizes the issuance of 942,817 shares of common stock under purchase rights granted to our employees. The number of shares of common stock reserved for issuance automatically increases on January 1 of each calendar year, through January 1, 2031, by the lesser of (i) 1 % of the total number of shares of common stock outstanding on the last day of the fiscal year before the date of the automatic increase (determining on an as-converted to voting common stock basis, without regard to any limitations on the conversion of the non-voting common stock); and (ii) such number of shares of common stock that would cause the aggregate number of shares of common stock then reserved for issuance under the ESPP to equal 1,060,017 shares; provided that before the date of any such increase, the Company’s board of directors may determine that such increase will be for a lesser amount of shares. The ESPP permits eligible employees, who elect to participate in an offering under the ESPP, to contribute up to 15 % of their eligible earnings (as defined in the ESPP) towards the purchase of shares of common stock. Unless otherwise determined by the Company's board of directors, the price at which stock is purchased under the ESPP is equal to 85 % of the fair market value of the Company’s common stock on the commencement date of each offering period or the relevant purchase date, whichever is lower. There are certain service requirements for an employee to be eligible to participate in the ESPP, and no employee may purchase shares under the ESPP at a rate in excess of $ 25,000 worth of common stock (as determined in accordance with the ESPP). Offering durations under the ESPP may not be longer than 27 months , and the Company may specify shorter purchase periods within each offering. The ESPP is considered a compensatory plan as defined by the authoritative guidance for stock-based compensation. As of March 31, 2024, the ESPP had not yet been implemented.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 9. Commitments and Contingencies Leases The Company has a lease agreement for office space located at 4275 Executive Square, Suite 950, La Jolla, California 92037 where it currently occupies 11,266 square feet. The lease had an expiration date of December 31, 2024. Monthly rent payments for this space under the lease agreement are approximately $ 43,000 and will increase to approximately $ 44,000 in July 2024. In February 2024, we further amended our lease so that we will occupy all 15,960 square feet on the 9th floor of the building, estimated to be effective October 1, 2024. The lease expiration was extended from December 31, 2024 to December 31, 2030. Monthly rent payments will be approximately $ 62,000 per month and will increase by approximately 4.5 % each year, starting in 2026. We have rent abatement for months 2 and 3 of the new lease amendment. A security deposit of approximately $ 244,000 is included in other long-term assets on the unaudited condensed balance sheet as of March 31, 2024. For the three months ended March 31, 2024 and 2023, the Company recorded approximately $ 109,000 and $ 105,000 , respectively, in rent expense. The below table provides supplemental cash flow information related to leases as follows (in thousands): Three Months Ended March 31, 2024 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 105 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 3,603 Supplemental balance sheet information related to leases is as follows (in thousands, except lease term and discount rate): March 31, 2024 Operating leases Right-of-use assets $ 3,977 Right-of-use lease liabilities, current 315 Right-of-use lease liabilities, noncurrent 3,667 Total operating lease liabilities $ 3,982 Weighted-average remaining lease term Operating leases 6.2 years Weighted-average discount rate Operating leases 10.0 % Future minimum lease commitments are as follows as of March 31, 2024 (in thousands): Operating Leases Year Ending December 31, 2024 $ 409 2025 663 2026 785 2027 820 2028 856 Thereafter 1,829 Total lease payments 5,362 Less imputed interest ( 1,380 ) Total $ 3,982 Contingencies From time to time, the Company may become subject to claims or suits arising in the ordinary course of business. The Company will accrue a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. As of March 31, 2024 and December 31, 2023, the Company is not a party to any litigation.

Employment Benefits

Employment Benefits	3 Months Ended
	Mar. 31, 2024
Postemployment Benefits [Abstract]
Employment Benefits	Note 10. Employment Benefits Effective in June 2021, the Company established a 401(k) salary deferral plan for its employees. Employee contributions are voluntary and are determined on an individual basis, limited to the maximum amount allowable under federal tax regulations. The Company provides a safe harbor contribution of up to 4 % of the employee's compensation, not to exceed eligible limits, and subject to employee participation. For the three months ended March 31, 2024 and 2023, the Company incurred approximatel y $ 209,000 and $ 107,000 , respectively, in expenses related to the safe harbor contribution.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The Company’s financial statements are prepared in accordance with GAAP. The preparation of the Company’s financial statements requires the Company to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Such estimates include the accrual of R&D expenses and stock-based compensation. Management evaluates its estimates on an ongoing basis. Estimates are based on the Company’s historical experience, knowledge of current events and actions it may undertake in the future, and actual results may materially differ from these estimates and assumptions.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments which potentially subject the Company to significant concentration of credit risk consist of cash, cash equivalents and short-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits and invests in short-term investments with the primary objectives of seeking to preserve principal, achieve liquidity requirements and safeguard funds. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held and the nature, including the credit-ratings, of its short-term investments, but we have not eliminated all credit risk.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on short-term investments.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market funds, corporate debt securities, and obligations of U.S. government-sponsored enterprises. The carrying amounts reported in the unaudited condensed balance sheets for cash and cash equivalents are valued at cost, which approximates fair value. The following table provides a reconciliation of the components of cash, cash equivalents and restricted cash reported in the condensed balance sheets to the total of the amount presented in the condensed statements of cash flows: March 31, December 31, (in thousands) 2024 2023 Cash and cash equivalents $ 54,395 $ 14,331 Restricted cash included in other long-term assets 244 — Total cash, cash equivalents and restricted cash presented in the condensed statements of cash flows $ 54,639 $ 14,331 The restricted cash relates to deposits for the Company’s office lease. The deposit will be reduced to $ 90,000 on January 1, 2027 as long as there are no defaults under the lease, and the remaining restriction will lapse when the lease expires on December 31, 2030.
Short-Term Investments	Short-Term Investments Short-term investments primarily consist of commercial paper, corporate debt securities, and government and agency bonds. The Company has classified these investments as available-for-sale securities, as the sale of such investments may be required prior to maturity to implement management strategies, and therefore has classified all investments with maturity dates beyond three months at the date of purchase as current assets in the accompanying unaudited balance sheets. Any premium or discount arising at purchase is amortized and/or accreted to interest income as an adjustment to yield using the straight-line method over the life of the instrument. Investments are reported at their estimated fair value. Unrealized gains and losses are included in accumulated other comprehensive loss as a component of stockholders' equity until realized.
R&D Expenses	R&D Expenses R&D expenses are expensed in the periods in which they are incurred. External expenses consist primarily of payments to contract research organizations, outside consultants and other third parties in connection with the Company’s research, preclinical and clinical activities, process development, manufacturing activities, regulatory and other services. Certain R&D external expenses are recognized based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its service providers or the estimate of the level of service that has been performed at each reporting date. R&D expenses amounted to $ 13.2 million and $ 8.5 million for the three months ended March 31, 2024 and 2023, respectively.
Stock-Based Compensation	Stock-Based Compensation Stock-based awards are measured at fair value and compensation expense is recognized over the requisite service period. Forfeitures are accounted for in the period they occur. The Company determines the fair value of each stock-based award on the date of grant using the Black-Scholes option pricing model which requires the input of subjective assumptions, including price volatility of the underlying stock, risk-free interest rate, dividend yield, and expected term of the option.
Leases	Leases The Company determines if an arrangement is a lease or contains lease components at inception. Lease terms are determined at the commencement date by considering whether renewal options and termination options, if any, are reasonably assured of exercise. For long-term operating leases, the Company recognizes a lease liability and a right-of-use (ROU) asset on its balance sheets and recognizes lease expense on a straight-line basis over the lease term. The lease liability is determined as the present value of future lease payments using the discount rate implicit in the lease or, if the implicit rate is not readily determinable, an estimate of the Company’s incremental borrowing rate. The ROU asset is based on the lease liability, adjusted for any prepaid or deferred rent. The Company only has operating leases and does not have any financing leases.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Since the Company had a net loss in each of the periods presented, basic and diluted net loss per share of common stock are the same. The table below provides potentially dilutive securities not included in the calculation of the diluted net loss per share as it would be anti-dilutive: Three Months Ended March 31, 2024 2023 Options to purchase common stock 5,537,267 3,877,556 Restricted stock awards, issued but unvested 150,660 — Total 5,687,927 3,877,556
Recent Accounting Pronouncements	Recent Accounting Pronouncements The Company does not believe that any recently issued, but not effective, accounting standards, if currently adopted, would have a material effect on our condensed financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Three Months Ended March 31, 2024 2023 Options to purchase common stock 5,537,267 3,877,556 Restricted stock awards, issued but unvested 150,660 — Total 5,687,927 3,877,556
Schedule of cash equivalents and restricted cash	The following table provides a reconciliation of the components of cash, cash equivalents and restricted cash reported in the condensed balance sheets to the total of the amount presented in the condensed statements of cash flows: March 31, December 31, (in thousands) 2024 2023 Cash and cash equivalents $ 54,395 $ 14,331 Restricted cash included in other long-term assets 244 — Total cash, cash equivalents and restricted cash presented in the condensed statements of cash flows $ 54,639 $ 14,331

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Summary of Company's Financial Assets Recognized at Fair Value	The following table summarizes the Company's financial instruments measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023. Fair Value Measurements at (in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of March 31, 2024 Assets: Money market funds $ 46,086 $ 46,086 $ — $ — Commercial paper $ 53,749 $ — $ 53,749 $ — Corporate debt securities 57,045 — 57,045 — Government and agency securities 160,843 150,812 10,031 — Total assets measured at fair value $ 317,723 $ 196,898 $ 120,825 $ — As of December 31, 2023 Assets: Money market funds $ 11,196 $ 11,196 $ — $ — Commercial paper $ 16,806 $ — $ 16,806 $ — Corporate debt securities 4,256 — 4,256 — Government and agency securities 13,105 13,105 — — Total assets measured at fair value $ 45,363 $ 24,301 $ 21,062 $ —

Short-Term Investments (Tables)

Short-Term Investments (Tables)	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents [Abstract]
Summary of Short-Term Investments	The following table summarizes short-term investments: As of March 31, 2024 Unrealized (in thousands) Amortized Cost Gains Losses Estimated Fair Value Commercial paper $ 50,863 $ — $ ( 104 ) $ 50,759 Corporate debt securities 57,260 — ( 215 ) 57,045 Government and agency securities 158,889 1 ( 46 ) 158,844 Total short-term investments $ 267,012 $ 1 $ ( 365 ) $ 266,648 As of December 31, 2023 Unrealized (in thousands) Amortized Cost Gains Losses Estimated Fair Value Commercial paper $ 16,813 $ — $ ( 7 ) $ 16,806 Corporate debt securities 4,277 — ( 21 ) 4,256 Government and agency securities 13,155 2 ( 52 ) 13,105 Total short-term investments $ 34,245 $ 2 $ ( 80 ) $ 34,167
Summary of Maturity of the Short-Term Investments	The following table summarizes the maturities of the Company's short-term investments at March 31, 2024: (in thousands) Amortized Cost Estimated Fair Value Due in one year or less $ 232,745 $ 232,489 Due in one to two years 34,267 34,159 Total short-term investments $ 267,012 $ 266,648
Summary of Available-for-sale Investments	The following table shows the Company’s available-for-sale investments’ gross unrealized losses and fair value aggregated by investment category and length of time that individual securities have been in a continuous loss position, at March 31, 2024 and December 31, 2023: As of March 31, 2024 Less than 12 months More than 12 months Total (in thousands) Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Commercial paper 15 $ 50,759 $ ( 104 ) — $ — $ — 15 $ 50,759 $ ( 104 ) Corporate debt securities 19 57,045 ( 215 ) — — — 19 57,045 ( 215 ) Government and agency securities 11 134,079 ( 32 ) 2 3,189 ( 14 ) 13 137,268 ( 46 ) 45 $ 241,883 $ ( 351 ) 2 $ 3,189 $ ( 14 ) 47 $ 245,072 $ ( 365 ) As of December 31, 2023 Less than 12 months More than 12 months Total (in thousands) Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Count Fair Value Unrealized Losses Commercial paper 8 $ 16,806 $ ( 7 ) — $ — $ — 8 $ 16,806 $ ( 7 ) Corporate debt securities — — — 3 4,256 ( 21 ) 3 4,256 ( 21 ) Government and agency securities — — — 2 3,149 ( 52 ) 2 3,149 ( 52 ) 8 $ 16,806 $ ( 7 ) 5 $ 7,405 $ ( 73 ) 13 $ 24,211 $ ( 80 )

Accrued Other Expenses (Tables)

Accrued Other Expenses (Tables)	3 Months Ended
	Mar. 31, 2024
Accrued Liabilities, Current [Abstract]
Summary of Accrued Other Expenses	Accrued other expenses consisted of t he following: As of (in thousands) March 31, 2024 December 31, 2023 Accrued legal and accounting fees $ 257 $ 40 Accrued consulting fees 177 218 Accrued taxes 50 40 Accrued travel expenses 27 43 Accrued computer related expenses 11 15 Accrued other 50 12 Total $ 572 $ 368

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Schedule of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit)	The following tables document the changes in stockholders' equity for the three months ended March 31, 2024 and 2023 (unaudited): Voting Common Stock Non-Voting Common Stock (in thousands, except shares) Number of Shares Amount Number of Shares Amount Additional Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity Balance at December 31, 2023 22,096,494 $ 2 2,420,755 $ — $ 181,563 $ ( 78 ) $ ( 140,564 ) $ 40,923 Issuance of common stock in follow-on public offering 11,500,000 1 — — 241,499 — — 241,500 Issuance of non-voting common stock in PIPE financing — — 2,850,000 — 59,850 — — 59,850 Financing related fees — — — — ( 15,088 ) — — ( 15,088 ) Stock-based compensation — — — — 1,749 — — 1,749 Stock option exercises 10,996 — — — 48 — — 48 Unrealized loss on short-term investments, net — — — — — ( 288 ) — ( 288 ) Net loss — — — — — — ( 14,986 ) ( 14,986 ) Balance at March 31, 2024 33,607,490 $ 3 5,270,755 $ — $ 469,621 $ ( 366 ) $ ( 155,550 ) $ 313,708 Voting Common Stock Non-Voting Common Stock (in thousands, except shares) Number of Shares Amount Number of Shares Amount Additional Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity Balance at December 31, 2022 13,585,950 $ 1 3,629,400 $ — $ 148,303 $ ( 692 ) $ ( 86,142 ) $ 61,470 Issuance of common stock in follow-on public offering 5,750,000 1 — — 21,187 — — 21,188 Conversion of non-voting common stock to voting common stock 1,208,645 ( 1,208,645 ) — — Financing related fees ( 37 ) ( 37 ) Stock-based compensation — — — — 697 — — 697 Unrealized gain on short-term investments, net — — — — — 271 — 271 Net loss — — — — — — ( 11,456 ) ( 11,456 ) Balance at March 31, 2023 20,544,595 $ 2 2,420,755 $ — $ 170,150 $ ( 421 ) $ ( 97,598 ) $ 72,133

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Stock Option Activity	A summary of the Company’s stock option activity is as follows: Number of Options Outstanding Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (in Years) Aggregate Intrinsic Value Balance at December 31, 2023 3,856,819 $ 5.10 8.3 $ 5,678 Options granted 1,708,014 19.92 Options exercised ( 10,996 ) 4.40 Options forfeited/cancelled ( 16,570 ) 8.95 Balance at March 31, 2024 5,537,267 $ 9.66 8.6 $ 66,208 Vested and expected to vest at March 31, 2024 5,537,267 $ 9.66 8.6 $ 66,208 Options exercisable at March 31, 2024 2,018,876 $ 5.47 7.6 $ 32,573
Summary of Weighted Average Grant Date Fair Values and Weighted Average Assumptions used to calculate Fair Value of Options Granted	The following table presents the weighted-average assumptions used for the stock option grants for the three months ended March 31, 2024 and 2023, along with the related grant date fair value: Three Months Ended March 31, 2024 2023 Stock price $ 19.92 $ 4.37 Risk-free interest rate 4.14 % 3.83 % Dividend yield 0.00 % 0.00 % Expected volatility 83.36 % 77.55 % Expected life (years) 6.0 6.0 Estimated grant date fair value per share of award granted $ 14.55 $ 3.05
Summary of Company's Restricted Stock Unit (RSU) Activity	A summary of the Company’s restricted stock unit (RSU) activity is as follows: Number of RSUs Outstanding Weighted-Average Grant Date Fair Value Balance at December 31, 2023 — $ — RSUs granted 151,500 19.32 RSUs vested — — RSUs forfeited/cancelled ( 840 ) 19.32 Balance at March 31, 2024 150,660 $ 19.32 RSUs vest annually over four years from the grant date.
Schedule of Stock-Based Compensation Expense Recognized for all Equity Awards and Reported in the Statements of Operations and Comprehensive Loss	Stock-based compensation expense recognized for all equity awards has been reported in the statements of operations and comprehensive loss as follows: Three Months Ended March 31, (in thousands) 2024 2023 Research and development $ 820 $ 339 General and administrative 929 358 Total $ 1,749 $ 697

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Supplemental Cash Flow Information Related to Leases	The below table provides supplemental cash flow information related to leases as follows (in thousands): Three Months Ended March 31, 2024 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 105 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 3,603
Schedule of Supplemental Balance Sheet Information Related to Leases	Supplemental balance sheet information related to leases is as follows (in thousands, except lease term and discount rate): March 31, 2024 Operating leases Right-of-use assets $ 3,977 Right-of-use lease liabilities, current 315 Right-of-use lease liabilities, noncurrent 3,667 Total operating lease liabilities $ 3,982 Weighted-average remaining lease term Operating leases 6.2 years Weighted-average discount rate Operating leases 10.0 %
Schedule of Future Minimum Lease Commitments	Future minimum lease commitments are as follows as of March 31, 2024 (in thousands): Operating Leases Year Ending December 31, 2024 $ 409 2025 663 2026 785 2027 820 2028 856 Thereafter 1,829 Total lease payments 5,362 Less imputed interest ( 1,380 ) Total $ 3,982

Organization and Basis of Pre_2

Organization and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (155,550)	$ (140,564)
Cash, cash equivalents and investment securities	321,000
Working capital	$ 313,200

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Jan. 01, 2027
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Research and development expenses	$ 13,170	$ 8,530
Subsequent Event [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reduced in deposit			$ 90,000
ASU 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Research and development expenses	$ 13,200	$ 8,500

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	5,687,927	3,877,556
Options To Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	5,537,267	3,877,556
Restricted Stock Awards, Issued But Unvested
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	150,660	0

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Cash Equivalents And Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Cash and cash equivalents	$ 54,395	$ 14,331
Restricted cash included in other long-term assets	244	0
Total cash, cash equivalents and restricted cash presented in the condensed statements of cash flows	$ 54,639	$ 14,331	$ 25,121	$ 10,775

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Company's Financial Assets Recognized at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	$ 266,648	$ 34,167
Total assets measured at fair value	317,723	45,363
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	46,086	11,196
Government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	160,843	13,105
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	53,749	16,806
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	57,045	4,256
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	196,898	24,301
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	46,086	11,196
Level 1 [Member] | Government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	150,812	13,105
Level 1 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 1 [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	120,825	21,062
Level 2 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 2 [Member] | Government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	10,031	0
Level 2 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	53,749	16,806
Level 2 [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	57,045	4,256
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 3 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 3 [Member] | Government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 3 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0	0
Level 3 [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	$ 0	$ 0

Short-Term Investments - Summar

Short-Term Investments - Summary of Short-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 267,012	$ 34,245
Unrealized Gains	1	2
Unrealized Losses	(365)	(80)
Estimated Fair Value	266,648	34,167
Commercial paper
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	50,863	16,813
Unrealized Gains	0	0
Unrealized Losses	(104)	(7)
Estimated Fair Value	50,759	16,806
Corporate debt securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	57,260	4,277
Unrealized Gains	0	0
Unrealized Losses	(215)	(21)
Estimated Fair Value	57,045	4,256
Government and agency securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	158,889	13,155
Unrealized Gains	1	2
Unrealized Losses	(46)	(52)
Estimated Fair Value	$ 158,844	$ 13,105

Short-Term Investments - Summ_2

Short-Term Investments - Summary of Maturity of the Short-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Due in one year or less, amortized cost	$ 232,745
Due in one to two years, amortized cost	34,267
Amortized Cost	267,012	$ 34,245
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Due in one year or less, fair value	232,489
Due in one to two years, fair value	34,159
Estimated Fair Value	$ 266,648	$ 34,167

Short-Term Investments - Summ_3

Short-Term Investments - Summary of Available-for-sale Investments (Details) $ in Thousands	Mar. 31, 2024 USD ($) Securities	Dec. 31, 2023 USD ($) Securities
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale Investments, Less than 12 months, Count | Securities	45	8
Available-for-sale Investments, Less than 12 months, Fair Value	$ 241,883	$ 16,806
Available-for-sale Investments, Less than 12 months, Unrealized Losses	$ (351)	$ (7)
Available-for-sale Investments, More than 12 months, Count | Securities	2	5
Available-for-sale Investments, More than 12 months, Fair value	$ 3,189	$ 7,405
Available-for-sale Investments, More than 12 months, Unrealized Losses	$ (14)	$ (73)
Available-for-sale Investments, Count | Securities	47	13
Available-for-sale Investments, Fair value	$ 245,072	$ 24,211
Available-for-sale Investments, Unrealized Losses	$ (365)	$ (80)
Commercial paper
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale Investments, Less than 12 months, Count | Securities	15	8
Available-for-sale Investments, Less than 12 months, Fair Value	$ 50,759	$ 16,806
Available-for-sale Investments, Less than 12 months, Unrealized Losses	$ (104)	$ (7)
Available-for-sale Investments, More than 12 months, Count | Securities	0	0
Available-for-sale Investments, More than 12 months, Fair value	$ 0	$ 0
Available-for-sale Investments, More than 12 months, Unrealized Losses	$ 0	$ 0
Available-for-sale Investments, Count | Securities	15	8
Available-for-sale Investments, Fair value	$ 50,759	$ 16,806
Available-for-sale Investments, Unrealized Losses	$ (104)	$ (7)
Corporate debt securities
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale Investments, Less than 12 months, Count | Securities	19	0
Available-for-sale Investments, Less than 12 months, Fair Value	$ 57,045	$ 0
Available-for-sale Investments, Less than 12 months, Unrealized Losses	$ (215)	$ 0
Available-for-sale Investments, More than 12 months, Count | Securities	0	3
Available-for-sale Investments, More than 12 months, Fair value	$ 0	$ 4,256
Available-for-sale Investments, More than 12 months, Unrealized Losses	$ 0	$ (21)
Available-for-sale Investments, Count | Securities	19	3
Available-for-sale Investments, Fair value	$ 57,045	$ 4,256
Available-for-sale Investments, Unrealized Losses	$ (215)	$ (21)
Government and agency securities
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale Investments, Less than 12 months, Count | Securities	11	0
Available-for-sale Investments, Less than 12 months, Fair Value	$ 134,079	$ 0
Available-for-sale Investments, Less than 12 months, Unrealized Losses	$ (32)	$ 0
Available-for-sale Investments, More than 12 months, Count | Securities	2	2
Available-for-sale Investments, More than 12 months, Fair value	$ 3,189	$ 3,149
Available-for-sale Investments, More than 12 months, Unrealized Losses	$ (14)	$ (52)
Available-for-sale Investments, Count | Securities	13	2
Available-for-sale Investments, Fair value	$ 137,268	$ 3,149
Available-for-sale Investments, Unrealized Losses	$ (46)	$ (52)

Accrued Other Expenses - Summar

Accrued Other Expenses - Summary of Accrued Other Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Accrued legal and accounting fees	$ 257	$ 40
Accrued consulting fees	177	218
Accrued taxes	50	40
Accrued travel expenses	27	43
Accrued computer related expenses	11	15
Accrued other	50	12
Total	$ 572	$ 368

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	Jan. 31, 2024	Feb. 28, 2023	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Mar. 31, 2021
Common stock, shares authorized			300,000,000		300,000,000
Preferred stock, shares authorized			10,000,000		10,000,000	10,000,000
Common stock, shares outstanding			33,607,490		22,096,494
Stock issuance costs	$ 500	$ 400
Price per share	$ 21
Common stock, shares issued			33,607,490		22,096,494
Proceeds from issuance of common stock			$ 301,350	$ 23,000
Underwriters commissions	$ 14,500	$ 1,400
Non-Voting Common Stock [Member]
Common stock, shares authorized			10,000,000		10,000,000	10,000,000
Common stock, shares outstanding			5,270,755		2,420,755
Common stock, shares issued			5,270,755		2,420,755
Private Placement [Member]
Price Per Share			$ 21
Private Placement [Member] | Non-Voting Common Stock [Member]
Common stock, shares issued			2,850,000
Gross proceeds			$ 59,900
Over-Allotment Option [Member]
Common stock, shares issued	1,500,000	750,000
Follow on Public Offering [Member]
Raised public offering	$ 241,500	$ 23,000
Proceeds from issuance of common stock	$ 226,500	$ 21,200
Voting Common Stock [Member]
Common stock, shares authorized						300,000,000
Common stock, shares outstanding			33,607,490		22,096,494
Common stock shares sold			0		1,422,250
Price per share		$ 4
Common stock, shares issued	11,500,000	5,750,000
Gross proceeds					$ 8,800
Voting Common Stock [Member] | Maximum [Member]
Gross proceeds			$ 150,000		$ 75,000

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Beginning Balance, Value	$ 40,923	$ 61,470
Financing related fees	(15,088)	(37)
Stock-based compensation	1,749	697
Stock option exercises	$ 48
Stock option exercises, shares	10,996
Unrealized gain on short-term investments, net	$ (288)	271
Net loss	(14,986)	(11,456)
Ending Balance, Value	313,708	72,133
Follow On [Member]
Issuance of common stock in follow-on public offering	241,500	$ 21,188
Private Investment in Public Equity (PIPE) [Member]
Issuance of non-voting common stock in PIPE financing	$ 59,850
Non-Voting Common Stock [Member]
Beginning Balance , Shares	2,420,755	3,629,400
Conversion of non-voting common stock to voting common stock (in shares)		(1,208,645)
Ending Balance, Shares	5,270,755	2,420,755
Non-Voting Common Stock [Member] | Private Investment in Public Equity (PIPE) [Member]
Issuance of non-voting common stock in PIPE financing (in shares)	2,850,000
Voting Common Stock [Member]
Beginning Balance, Value	$ 2	$ 1
Beginning Balance , Shares	22,096,494	13,585,950
Conversion of non-voting common stock to voting common stock (in shares)		1,208,645
Stock option exercises, shares	10,996
Ending Balance, Value	$ 3	$ 2
Ending Balance, Shares	33,607,490	20,544,595
Voting Common Stock [Member] | Follow On [Member]
Issuance of common stock in follow-on public offering	$ 1	$ 1
Issuance of common stock in follow-on public offering (in shares)	11,500,000	5,750,000
Additional Paid-in Capital [Member]
Beginning Balance, Value	$ 181,563	$ 148,303
Financing related fees	(15,088)	(37)
Stock-based compensation	1,749	697
Stock option exercises	48
Ending Balance, Value	469,621	170,150
Additional Paid-in Capital [Member] | Follow On [Member]
Issuance of common stock in follow-on public offering	241,499	21,187
Additional Paid-in Capital [Member] | Private Investment in Public Equity (PIPE) [Member]
Issuance of non-voting common stock in PIPE financing	59,850
Accumulated Other Comprehensive Loss [Member]
Beginning Balance, Value	(78)	(692)
Unrealized gain on short-term investments, net	(288)	271
Ending Balance, Value	(366)	(421)
Accumulated Deficit [Member]
Beginning Balance, Value	(140,564)	(86,142)
Net loss	(14,986)	(11,456)
Ending Balance, Value	$ (155,550)	$ (97,598)

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options exercisable, vested stock options	1,917,244
Options exercisable, subject to early exercise provision	101,632
Number of shares outstanding	5,537,267		3,856,819
Number of shares, options granted	1,708,014
Total stock-based compensation expense	$ 1,749,000	$ 697,000
Cost not yet recognized, period for recognition	3 years	3 years 10 months 24 days
Percentage of shares of common stock outstanding	1%
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized for issuance	942,817
Employee stock purchase plan, eligible earnings contribution, percentage	15%
Employee stock purchase plan, shares purchase price as a percentage of market fair value	85%
Employee stock purchase plan, maximum shares purchased, value	$ 25,000
Employee stock purchase plan, maximum offering period	27 months
Shares reserved for future issuance	1,060,017
General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 929,000	$ 358,000
Research and Development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	820,000	339,000
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 30,000,000
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding	150,660		0
Total stock-based compensation expense	$ 100,000	$ 0
Unrecognized stock-based compensation expense	$ 2,800,000
2021 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding	5,537,267
Number of shares, options granted	953,056
2021 Equity Incentive Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized for issuance	1,000,000
2021 Equity Incentive Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized for issuance	6,640,983
2021 Equity Incentive Plan [Member] | Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding	150,660
2020 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant	0
2020 Equity Incentive Plan [Member] | Minimum [Member] | Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	1 year
2020 Equity Incentive Plan [Member] | Maximum [Member] | Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
Award expiration term	10 years

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Options [Roll Forward]
Number of Shares, Options outstanding, beginning balance	3,856,819
Number of Shares, Options granted	1,708,014
Number of Shares, Options exercised	(10,996)
Number of Shares, Options forfeited/cancelled	(16,570)
Number of Shares, Options outstanding, ending balance	5,537,267	3,856,819
Number of Shares, Options Vested and Expected to Vest	5,537,267
Number of Shares, Options exercisable	2,018,876
Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price Per share, Options outstanding, beginning balance	$ 5.1
Weighted Average Exercise Price Per share, Options granted	19.92
Weighted Average Exercise Price Per share, Options exercised	4.4
Weighted Average Exercise Price Per share, Options cancelled	8.95
Weighted Average Exercise Price Per share, Options outstanding, ending balance	9.66	$ 5.1
Weighted Average Exercise Price Per share, Options vested	9.66
Weighted Average Exercise Price Per share, Options exercisable	$ 5.47
Weighted Average Remaining Contractual Term (in Years) [Roll Forward]
Weighted Average Remaining Contractual Term, Options outstanding	8 years 7 months 6 days	8 years 3 months 18 days
Weighted Average Remaining Contractual Term, Options vested and expected to vest	8 years 7 months 6 days
Weighted Average Remaining Contractual Term, Options exercisable	7 years 7 months 6 days
Options outstanding, Intrinsic value	$ 66,208	$ 5,678
Aggregate Intrinsic Value, Vested and expected to vest	66,208
Options exercisable, Intrinsic value	$ 32,573

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Weighted Average Grant-Date Fair Values And Weighted Average Assumptions Used to Calculate Fair Value of Options Granted (Details) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock price	$ 19.92	$ 4.37
Risk-free interest rate	4.14%	3.83%
Dividend yield	0%	0%
Expected volatility	83.36%	77.55%
Expected life (years)	6 years	6 years
Estimated grant date fair value per share of award granted	$ 14.55	$ 3.05

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Company's Restricted Stock Unit (RSU) Activity (Details) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Number of Shares, Options outstanding, beginning balance	3,856,819
Number of Shares, Options outstanding, ending balance	5,537,267
Weighted-Average Grant Date Fair Value, Options granted	$ 14.55	$ 3.05
Restricted Stock Units [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Number of Shares, Options outstanding, beginning balance	0
RSU granted	151,500
RSUs vested	0
RSUs forfeited/cancelled	(840)
Number of Shares, Options outstanding, ending balance	150,660
Weighted-Average Grant Date Fair Value, beginning balance	$ 0
Weighted-Average Grant Date Fair Value, Options granted	19.32
Weighted-Average Grant Date Fair Value, Options exercised	0
Weighted-Average Grant Date Fair Value, Options forfeited/cancelled	19.32
Weighted-Average Grant Date Fair Value, ending balance	$ 19.32

Stock-Based Compensation Expens

Stock-Based Compensation Expense - Schedule of Stock-Based Compensation Expense Recognized for all Equity Awards and Reported in the Statements of Operations and Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,749	$ 697
Research and Development [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	820	339
General and Administrative [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 929	$ 358

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)		1 Months Ended	3 Months Ended		12 Months Ended
	Jul. 31, 2024 USD ($)	Feb. 29, 2024 USD ($) ft²	Mar. 31, 2024 USD ($) ft²	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Security deposit		$ 244,000,000
Percentage of increase in rent by second year		4.50%
Area of office space | ft²		15,960	11,266
Historical rent paid	$ 44,000,000
Future rent payment per month for first year		$ 62,000,000			$ 43,000,000
Total rent expense			$ 109,000	$ 105,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Supplemental Cash Flow Information Related to Leases (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 105
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	$ 3,603

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Supplemental Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Operating leases
Right-of-use assets	$ 3,977	$ 472
Right-of-use lease liabilities, current	315	475
Right-of-use lease liabilities, noncurrent	3,667	$ 0
Total operating lease liabilities	$ 3,982
Weighted-average remaining lease term
Operating leases	6 years 2 months 12 days
Weighted-average discount rate
Operating leases	10%

Commitments and Contingencies_4

Commitments and Contingencies - Schedule of Future Minimum Lease Commitments (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2024	$ 409
2025	663
2026	785
2027	820
2028	856
Thereafter	1,829
Total lease payments	5,362
Less imputed interest	(1,380)
Total	$ 3,982

Employment Benefits - Additiona

Employment Benefits - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Postemployment Benefits [Abstract]
Company Provides Safe Harbor Contribution	4%
Expenses Related To Contribution Plan	$ 209,000	$ 107,000