0000950170-24-096639 | 10-Q | XBRL Viewer

Net Loss Per Share Attributable to Common Stockholders (Tables)

6 Months Ended

Jun. 30, 2024

Summary of Potentially Dilutive Securities Not Included in the Diluted Per Share Calculations

The following equity instruments were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented:


	June 30,
	2024		2023
Stock options		7,525,626		7,390,547
Estimated shares issuable under the employee stock purchase plan		86,292		59,616
Unvested restricted stock units		1,707,599		958,121
Total		9,319,517		8,408,284

Summary of Significant Accounting Policies	6 Months Ended
Summary of Significant Accounting Policies	Jun. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Such management estimates include, but are not limited to, those related to revenue recognition, marketable securities, manufacturing accruals, accrued research and development expenses, stock-based compensation, operating lease right-of-use (ROU) assets and liabilities, income tax uncertainties and the valuation of deferred tax assets. The Company bases its estimates on its historical experience and also on assumptions that it believes are reasonable; however, actual results could significantly differ from those estimates. The most significant estimates and assumptions that management considers in the preparation of our financial statements relate to revenue recognition, accrued research and development costs, and leases. Segments The Company operates and manages its business as one reportable and operating segment, which is the business of developing engineered IgM antibodies for the treatment of cancer and autoimmune and inflammatory diseases. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating and evaluating financial performance. All long-lived assets are maintained in, and all losses are attributable to, the United States of America. Concentration of Credit Risk and Other Risks and Uncertainties Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company invests in money market funds, U.S. treasury securities, corporate bonds, commercial paper, and U.S. government agency securities. The Company maintains bank deposits in federally insured financial institutions and these deposits may exceed federally insured limits. The Company is exposed to credit risk in the event of a default by the financial institutions holding its cash, cash equivalents, and restricted cash, and bond issuers to the extent recorded on the balance sheets. The Company’s investment policy limits investments to high credit quality securities issued by the U.S. government and its agencies, highly rated banks, and corporate issuers, subject to certain concentration limits and restrictions on maturities. The Company has not experienced any material losses on its deposits of cash, cash equivalents, and marketable securities. The Company’s future results of operations involve a number of other risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the Company’s early stages of clinical drug development; uncertainties related to the use of engineered IgM antibodies, which is a novel and unproven therapeutic approach; the Company’s ability to advance product candidates into, and successfully complete, clinical trials on the timelines it projects; the Company’s ability to adequately demonstrate sufficient safety and efficacy of its product candidates; the Company’s ability to enroll patients in its ongoing and future clinical trials; the Company’s ability to successfully manufacture and supply its product candidates for clinical trials; the occurrence of any event or circumstance that could give rise to the termination of the Company’s collaborations with third parties; the Company’s ability to obtain additional capital to finance its operations; uncertainties related to the projections of the size of patient populations suffering from the diseases the Company is targeting; the Company’s ability to obtain, maintain, and protect its intellectual property rights; developments relating to the Company’s competitors and its industry, including competing product candidates and therapies; general economic and market conditions; and other risks and uncertainties, including those more fully described in the “Risk Factors” section of this Quarterly Report on Form 10-Q. The Company’s product candidates will require approvals from the U.S. Food and Drug Administration (FDA) and comparable foreign regulatory agencies prior to commercial sales in their respective jurisdictions. There can be no assurance that any product candidates will receive the necessary approvals. If the Company was denied approval, approval was delayed or the Company was unable to maintain approval for any product candidate, it could have a materially adverse impact on the Company. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash and cash equivalents. Cash equivalents consist primarily of amounts invested in money market funds, commercial paper, U.S. treasury securities, and U.S. government agency securities and are stated at fair value. Restricted cash consists of the remaining unused portion of a grant received from a non-profit organization which the Company will continue to utilize as it incurs expenses for services performed under the grant agreement. Marketable Securities The Company’s marketable securities have been classified and accounted for as available-for-sale securities. Fixed income securities consist of U.S. treasury securities, U.S. government agency securities, corporate bonds, and commercial paper. The specific identification method is used to determine the cost basis of fixed income securities sold. These securities are recorded on the condensed consolidated balance sheets at fair value. Unrealized gains and losses on these securities are included as a separate component of accumulated other comprehensive loss. The cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in other income (expense). All available-for-sale securities are considered available to support current operations and are classified as current assets. The Company presents any credit losses identified as an allowance rather than as a reduction in the amortized cost of the available-for-sale securities. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value and recognized in other income (expense) in the condensed consolidated statements of operations. If neither criteria is met, the Company evaluates whether the decline in fair value is related to credit-related factors or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. Credit-related impairment losses, limited by the amount that the fair value is less than the amortized cost basis, are recorded through an allowance for credit losses in other income (expense). Any unrealized losses from declines in fair value below the amortized cost basis as a result of non-credit factors are recognized in accumulated other comprehensive income (loss), net of tax as a separate component of stockholders’ equity, along with unrealized gains. Realized gains and losses and declines in fair value, if any, on available-for-sale securities are included in other income (expense) in the condensed consolidated statements of operations. For purposes of identifying and measuring credit-related impairments, the Company’s policy is to exclude applicable accrued interest from both the fair value and amortized cost basis of the related security. The Company has elected to write-off uncollectible accrued interest receivable balances in a timely manner, which is defined by the Company as when interest due becomes 90 days delinquent. The accrued interest write-off will be recorded by reversing interest income. Accrued interest receivable is recorded to prepaid expenses and other current assets on the condensed consolidated balance sheets. Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is determined using the straight-line method over the estimated useful lives of the respective assets, generally three to five years. Leasehold improvements are depreciated using the straight-line method over the shorter of the lease term or the estimated useful economic lives of the related assets. Assets are held in construction in progress until placed in service, upon which date, we begin to depreciate these assets. Upon retirement or sale of the assets, the cost and related accumulated depreciation and amortization are removed from the condensed consolidated balance sheets and the resulting gain or loss are recorded to the condensed consolidated statements of operations. Repairs and maintenance are charged to the condensed consolidated statements of operations as incurred. Leases The Company determines if an arrangement is a lease at inception. In addition, the Company determines whether leases meet the classification criteria of a finance or operating lease at the lease commencement date considering: (1) whether the lease transfers ownership of the underlying asset to the lessee at the end of the lease term, (2) whether the lease grants the lessee an option to purchase the underlying asset that the lessee is reasonably certain to exercise, (3) whether the lease term is for a major part of the remaining economic life of the underlying asset, (4) whether the present value of the sum of the lease payments and residual value guaranteed by the lessee equals or exceeds substantially all of the fair value of the underlying asset, and (5) whether the underlying asset is of such a specialized nature that it is expected to have no alternative use to the lessor at the end of the lease term. As of June 30, 2024, the Company's lease population consisted of real estate leases and the Company did not have finance leases. Operating leases are included in operating lease ROU assets and lease liabilities in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. In determining the present value of lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date if the rate implicit in the lease is not readily determinable. The Company determines the incremental borrowing rate based on an analysis of corporate bond yields with a credit rating similar to the Company. The determination of the Company’s incremental borrowing rate requires management judgment including the development of a synthetic credit rating and cost of debt as the Company currently does not carry any debt. The Company believes that the estimates used in determining the incremental borrowing rate are reasonable based upon current facts and circumstances. Applying different judgments to the same facts and circumstances could result in the estimated amounts to vary. The operating lease ROU assets also include adjustments for prepayments and accrued lease payments and exclude lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options. Operating lease cost is recognized on a straight-line basis over the expected lease term. Variable lease costs represent payments that are dependent on usage, a rate or index. Variable lease cost primarily relates to common area maintenance charges. Lease agreements that include lease and non-lease components are accounted for as a single lease component. Lease agreements with a noncancelable term of less than 12 months are not recorded on the Company’s condensed consolidated balance sheets. Impairment of Long-Lived Assets The Company evaluates the carrying amount of its long-lived assets, such as property and equipment, whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition are less than the carrying amount of the asset. There were no impairments of long-lived assets for the three and six months ended June 30, 2024 and 2023. Fair Value Measurement The Company applies fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the condensed consolidated financial statements on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. 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, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows: Level 1—Observable inputs, such as quoted prices in active markets for identical assets or liabilities at the measurement date. Level 2—Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3—Unobservable inputs which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. Financial instruments classified within Level 2 of the fair value hierarchy are valued based on other observable inputs, including broker or dealer quotations or alternative pricing sources. When quoted prices in active markets for identical assets or liabilities are not available, the Company relies on non-binding quotes from its investment managers, which are based on proprietary valuation models of independent pricing services. These models generally use inputs such as observable market data, quoted market prices for similar instruments, or historical pricing trends of a security relative to its peers. Revenue Recognition For arrangements or transactions between participants determined to be within the scope of Accounting Standard Codification (ASC) Topic 606, “Revenue from Contracts with Customers” (Topic 606) the Company performs the following steps to determine the appropriate amount of revenue to be recognized as the Company fulfills its obligations: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company has entered into and may enter into additional collaboration agreements in the future under which it may obtain upfront payments, milestone payments, royalty payments, profit sharing, and other fees. Promises under these arrangements may include intellectual property licenses, research and development services, and the participation in joint committees. At contract inception, the Company assesses the goods or services promised and enforceable in a contract with a customer and identifies those distinct goods and services that represent a performance obligation. In assessing whether a promised good or service is distinct, and therefore a performance obligation, the Company considers factors such as the nature of the research, stage of development of the targets, manufacturing and commercialization capabilities of the customer and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, the Company combines that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct. Promised goods and services that are not material in the context of the contract are not considered performance obligations. Additional goods or services that are exercisable at a customer’s discretion, including substitution rights, are assessed to determine if they provide a material right to the customer and if so, they are considered performance obligations. The transaction price is the amount of consideration to which the Company expects to be entitled in exchange for transferring promised goods or services to a customer. The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Non-refundable upfront payments are considered fixed consideration and included in the transaction price. If an arrangement includes development, regulatory or commercial milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. The Company includes the amount of estimated variable consideration, including milestones, in the transaction price to the extent that it is probable that a significant reversal of cumulative revenue recognized will not occur. Milestone payments that are not within the Company’s control or the licensee’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. For arrangements with licenses of intellectual property that include sales-based royalties, including milestone payments based on the level of sales, and if the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. If it is determined that multiple performance obligations exist, the transaction price is allocated at the inception of the agreement to all identified performance obligations based on the relative standalone selling prices (SSP), unless the consideration is variable and meets the criteria to be allocated entirely to one or more, but not all, performance obligations in the contract. The relative SSP for each deliverable is estimated using objective evidence if it is available. If SSP is not directly observable the Company estimates the SSP at an amount that would result in the allocation of the transaction price in an amount that depicts the amount of consideration to which the entity expects to be entitled in exchange for transferring the promised goods or services to the customer, using methods such as the expected cost plus margin approach. Once the transaction price has been allocated to a performance obligation using the applicable methodology, it is not subject to reassessment for subsequent changes in standalone selling prices. Collaboration revenue is recognized when, or as, the Company satisfies a performance obligation. The Company recognizes revenue over time by measuring the progress toward complete satisfaction of the relevant performance obligation using an appropriate input method based on the nature of the good or service promised to the customer. After contract inception, the transaction price is reassessed at every period end and updated for changes such as resolution of uncertain events. Management may be required to exercise considerable judgment in estimating revenue to be recognized. Judgment is required in identifying performance obligations, estimating the transaction price, including variable consideration, estimating the standalone selling prices of identified performance obligations, and applying the input method for revenue recognition, including the estimated budgets for each performance obligation. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s condensed consolidated balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Amounts recognized as revenue prior to receipt are recorded as contract assets in the Company’s condensed consolidated balance sheets. If the Company expects to have an unconditional right to receive consideration in the next twelve months, this will be classified in current assets. A net contract asset or liability is presented for each contract with a customer. Contract modifications occur when the price and /or scope of an arrangement changes. If the modification consists of adding new distinct goods or services in exchange for consideration that reflects standalone selling prices of these goods and services, the modification is accounted for as a separate contract with the customer. Otherwise, if the remaining goods and services are distinct from those previously provided, the existing contract is considered terminated, and the remaining consideration is allocated to the remaining goods and services as if this was a newly signed contract. If the remaining goods and services are not distinct from those previously provided, the effects of the modification are accounted for in a manner similar to the effect of a change in the estimated measure of progress, with cumulative catch-up in revenue recorded at the time of the modification. If some of the remaining goods and services are distinct from those previously provided and others are not, the Company applies principles consistent with the objectives of the modification guidance to account for the effects of the modification. Collaborative Arrangements The Company analyzes its agreements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (Topic 808). These assessments are performed throughout the life of the arrangements based on changes in the responsibilities of all parties in the arrangement. Research and Development Expenses The Company expenses research and development costs as they are incurred. Research and development expenses consist primarily of: (i) personnel-related expenses, including salaries, benefits and stock-based compensation expense, for personnel in the Company’s research and development functions; (ii) fees paid to third parties such as contractors, consultants and contract research organizations (CROs) for conducting clinical trials, and other costs related to clinical and preclinical testing; (iii) costs related to acquiring and manufacturing research and clinical trial materials, including under agreements with third parties such as contract manufacturing organizations (CMOs), and other vendors; (iv) costs related to the preparation of regulatory submissions; (v) expenses related to laboratory supplies and services; (vi) fees under license agreements where no alternative future use exists; and (vii) depreciation of equipment and facilities expenses. Accrued Research and Development Expenses The Company records accruals for estimated costs of research, preclinical studies, clinical trials, and manufacturing, which are significant components of research and development expenses. A substantial portion of the Company’s ongoing research and development activities is conducted by third-party service providers, CROs and CMOs. The Company’s contracts with CROs generally include pass-through fees such as laboratory supplies and services, regulatory expenses, investigator fees, travel costs and other miscellaneous costs, including shipping and printing fees. The Company’s contracts with the CMOs generally include fees such as initiation fees, reservation fees, verification run costs, materials and reagents expenses, taxes, etc. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to the Company under such contracts. The Company accrues the costs incurred under agreements with these third parties based on estimates of actual work completed in accordance with the respective agreements. The Company determines the estimated costs through discussions with internal personnel and external service providers as to the progress, or stage of completion or actual timeline (start-date and end-date) of the services and the agreed-upon fees to be paid for such services. In the event the Company makes advance payments, the payments are recorded as a prepaid expense and recognized as the services are performed. As actual costs become known, the Company adjusts its accruals. Although the Company does not expect its estimates to be materially different from amounts actually incurred, such estimates for the status and timing of services performed relative to the actual status and timing of services performed may vary and could result in the Company reporting amounts that are too high or too low in any particular period. The Company’s accrual is dependent, in part, upon the receipt of timely and accurate reporting from CROs and other third-party vendors. Variations in the assumptions used to estimate accruals including, but not limited to, the number of patients enrolled, the rate of patient enrollment and the actual services performed, may vary from the Company’s estimates, resulting in adjustments to clinical trial expenses in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect its financial condition and results of operations. Through June 30, 2024, there have been no material differences from the Company’s estimated accrued research and development expenses to actual expenses. Acquired In-Process Research and Development Expenses The Company has entered into agreements (see Note 5 – License Agreements) with third parties to acquire the rights to develop and potentially commercialize certain products. Such agreements generally require an initial payment by the Company when the contract is executed. The purchase of license rights for use in research and development activities, including product development, are expensed as incurred and are classified as research and development expense. Additionally, the Company may be obligated to make future royalty payments in the event the Company commercializes the technology and achieves a certain sales volume. In accordance with ASC Topic 730, Research and Development (Topic 730), expenditures for research and development, including upfront licensing fees and milestone payments associated with products not yet been approved by the FDA, are charged to research and development expense as incurred. Future contract milestone and/or royalty payments will be recognized as expense after the achievement of the milestone and the corresponding milestone payment is legally due. Stock-Based Compensation The Company accounts for stock-based compensation by measuring and recognizing compensation expense for all share-based awards made to employees, non-employees and directors based on estimated grant-date fair values. The Company uses the straight-line method to allocate compensation cost to reporting periods over the requisite service period, which is generally the vesting period. The grant date fair value of restricted stock units is estimated based on the closing stock price of the Company’s common stock on the date of grant. The grant date fair value of stock options granted to employees and directors is estimated using the Black-Scholes option-pricing model. The Company accounts for forfeitures as they occur. The fair value of each purchase right under the employee stock purchase plan (ESPP) is estimated at the beginning of the offering period using the Black-Scholes option pricing model and recorded as expense over the service period using the straight-line method. Income Taxes The Company accounts for income taxes using the liability method, whereby deferred tax asset and liability account balances are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company provides a valuation allowance when it is more likely than not that some portion, or all of the Company’s deferred tax assets will not be realized. The Company accounts for income tax contingencies using a benefit recognition model. If it considers that a tax position is more likely than not to be sustained upon audit, based solely on the technical merits of the position, it recognizes the benefit. The Company measures the benefit by determining the amount that is greater than 50% likely of being realized upon settlement, presuming that the tax position is examined by the appropriate taxing authority that has full knowledge of all relevant information. The Company is subject to taxation in the United States federal jurisdiction, and various state jurisdictions. The net operating loss and research and development credit carryforwards that are available for utilization in future years may be subject to examination by federal and state tax authorities. The Company’s policy is to recognize interest expense and penalties related to income tax matters as a component of income tax expense. As of June 30, 2024, there were no significant accruals for interest related to unrecognized tax benefits or tax penalties. Comprehensive Loss Comprehensive loss represents the net loss for the period and other comprehensive loss. Other comprehensive loss reflects certain gains and losses that are recorded as a component of stockholders’ equity and are not reflected in the condensed consolidated statements of operations. The Company’s other comprehensive loss consists of changes in unrealized gains and losses on available-for-sale securities. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock (including non-voting common stock and pre-funded warrants) outstanding during the period, without consideration for all other common stock equivalents. Shares of common stock into which the pre-funded warrants may be exercised are considered outstanding for the purposes of computing net loss per share because the shares may be issued for little or no consideration, are fully vested, and are exercisable after the original issuance date. Diluted net loss per share is the same as basic net loss per share, since the effects of potentially dilutive securities are antidilutive given the net loss for each period presented. Recently Issued Accounting Pronouncements In October 2023, the FASB issued Accounting Standards Update (ASU) 2023-06, Disclosure Improvements - Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative, which will impact various disclosure areas. The amendments in ASU 2023-06 will be effective on the date the related disclosures are removed from Regulation S-X or Regulation S-K by the SEC, and will no longer be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. The Company is currently evaluating the impacts of this standard on its related disclosures. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280), which improves reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023 and is applicable to public entities, including those that have a single reportable segment. Early adoption is permitted. The Company is currently evaluating the impacts of this standard on its condensed consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures, which amends the guidance in ASC 740, Income Taxes. The ASU is intended to improve the transparency of income tax disclosures by requiring (1) consistent categories and greater disaggregation of information in the rate reconciliation and (2) income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. The ASU's amendments are effective for public business entities for annual periods beginning after December 15, 2024. Entities are permitted to early adopt the standard for annual financial statements that have not yet been issued or made available for issuance. Adoption is permitted either prospectively or retrospectively. The Company will adopt this ASU on a prospective basis. The Company is currently evaluating the impact of this standard but does not expect any material impacts on its condensed consolidated financial statements and related disclosures.

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2024	Aug. 07, 2024
Document and Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Entity Registrant Name	IGM Biosciences, Inc.
Entity Central Index Key	0001496323
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	IGMS
Security Exchange Name	NASDAQ
Entity File Number	001-39045
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	77-0349194
Entity Address, Address Line One	325 E. Middlefield Road
Entity Address, City or Town	Mountain View
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94043
City Area Code	650
Local Phone Number	965-7873
Common Stock
Document and Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		33,931,686
Non-voting Common Stock
Document and Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		25,386,983

Stock-Based Compensation - Additional Information (Details) - 2018 Plan - shares	6 Months Ended
	Jun. 30, 2024	Jan. 01, 2024	Jan. 01, 2023
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Increase in number of shares		2,347,245	1,723,292
Outstanding stock including non-voting common stock, percent	4.00%
Common stock available for future issuance	3,623,814
Maximum
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Increase in number of shares	8,768,800

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Sanofi Agreement - Schedule of Contract liabilities for the periods (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Sanofi Agreement [Abstract]
Deferred revenue, beginning balance	$ 146,801	$ 148,931
Additions	0	0
Deductions	(1,751)	(970)
Deferred revenue, ending balance	$ 145,050	$ 147,961

Accrued Liabilities

6 Months Ended

Jun. 30, 2024

Balance Sheet Related Disclosures [Abstract]

Accrued Liabilities

Note 4. Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	June 30,		December 31,
	2024		2023
Accrued research and development materials and services	$	16,740	$	14,625
Accrued professional services		1,381		3,147
Accrued compensation		7,249		13,527
Other		1,091		245
Total accrued liabilities	$	26,461	$	31,544

Sanofi Agreement

6 Months Ended

Jun. 30, 2024

Sanofi Agreement [Abstract]

Sanofi Agreement

Note 7. Sanofi Agreement

In March 2022, the Company entered into a global collaboration and license agreement (the Sanofi Agreement) with Genzyme Corporation, a wholly owned subsidiary of Sanofi (Sanofi), which became effective in May 2022. Under the terms of the Sanofi Agreement, the Company agreed to generate, develop, manufacture and commercialize IgM antibodies directed to six primary targets, three of which were oncology targets and three of which were immunology targets.

In April 2024, Sanofi exercised its right to terminate the oncology collaboration targets effective June 2024. As a result of this termination, the Company has no further obligations to conduct research and development activities for such terminated targets and Sanofi retains no substitution rights for such terminated targets, pursuant to the terms of the agreement, and the collaboration will now focus exclusively on the immunology collaboration targets. The termination of the oncology targets will not affect any rights and obligations under the Sanofi Agreement with respect to the immunology targets.

For each immunology target collaboration program, the Company will continue to lead research and development activities, and assume related costs, through the completion of the first Phase 1 clinical trials for up to two candidates directed to each immunology target, after which Sanofi will be responsible for all future development and commercialization activities and related costs, in exchange for up to $1.065 billion in aggregate development, regulatory and commercial milestones per immunology target. Following the completion of the first Phase 1 clinical trials for each immunology target, Sanofi will be responsible for subsequent development activities, commercialization efforts, and related costs. The Company is eligible to receive tiered high single-digit to low-teen royalties on global net sales for licensed products related to immunology targets, subject to certain reductions and offsets.

Subject to earlier expiration in certain circumstances, the Sanofi Agreement expires on a licensed product-by-licensed product and country-by-country basis until the expiration of the applicable profit and loss share term or royalty term, as the case may be. Sanofi has the right to terminate the Sanofi Agreement on a collaboration target-by-collaboration target basis or country-by-country basis with or without cause, upon specified prior notice.

At the inception of the Sanofi Agreement, the Company identified promised goods and services, which consisted of the granting of intellectual property licenses and the performance of specified research, development and other various activities. The Company determined that for each of the six targets, the identified promised goods and services were not distinct from each other on a target-by-target basis. The licenses, considered to be functional intellectual property, were determined to not be capable of being distinct due to the specialized nature of the research, development, and other activities to be provided by the Company. Accordingly, the promised goods and services were combined together as one single performance obligation, on a target-by-target basis. The Company determined that the underlying promised goods and services for each of the six targets were both capable of being distinct and distinct within the context of the contract from each of the other targets. Therefore, the Company concluded that there were six performance obligations in the Sanofi Agreement, one for each target, that were comprised of the underlying promised goods and services. Other components and options within the Sanofi Agreement were determined to not provide Sanofi with free or discounted goods or services and therefore did not constitute a material right or were deemed immaterial in the context of the contract.

To determine the transaction price, the Company evaluates all the payments to be received during the duration of the contract. In May 2022, the Company received a $150.0 million upfront payment as part of the Sanofi Agreement. Additionally, in April 2022, Sanofi purchased non-voting common stock in connection with the Company’s public common stock offering. The Company concluded that at inception and as of June 30, 2024, the transaction price was $150.0 million and was comprised solely of the fixed non-refundable upfront payment. No consideration received from Sanofi as part of the April 2022 offering was deemed necessary to include in the transaction price as Sanofi purchased the shares at the same offering price as the other participating investors.

The potential development and regulatory milestone payments that the Company is eligible to receive were excluded from the transaction price, as the milestone amounts were fully constrained, since the milestones relate to successful achievement of certain development results and regulatory approvals, which might not be achieved. The Company determined that the royalties and commercial milestone payments relate predominantly to the license of intellectual property and are therefore excluded from the transaction price under the sales- or usage-based royalty exception of ASC 606. The Company will reevaluate the transaction price, including all constrained amounts, at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and the Company will adjust its estimate of the transaction price as necessary. The Company will recognize the royalties and commercial milestone payments as revenue when the associated sales occur, and relevant sales-based thresholds are met.

At the inception of the Sanofi Agreement, the Company allocated the transaction price based on the estimated SSP of each of the six performance obligations. The Company determined the SSP for each of the six performance obligations based on the estimated costs to complete the underlying activities of each performance obligation and included factors such as forecasted internal costs, estimated third-party expenditures, development timelines and scenarios, probability of target failures and selection of substitute targets, and program-specific factors. These estimated cost forecasts were based on observable data for both market and entity specific factors, such as considering the actual and expected costs of the Company’s existing research and development programs and adjusting for factors specific to the targets identified.

The Company recognizes revenue using an input method of costs incurred as a percentage of total estimated costs for each of the performance obligations under the contract. Costs consist primarily of internal personnel costs and third-party contract expenses related to the programs of the Sanofi Agreement. The cumulative effect of revisions to estimated costs to complete the Company’s performance obligations is recorded in the period in which changes are identified and amounts can be reasonably estimated.

The Company determined that Sanofi’s exercise of its right to terminate the oncology collaboration targets in April 2024 was a contract modification because it changed the scope of the contract by reducing the number of performance obligations under the agreement. The remaining performance obligations relating to the three immunology collaboration targets are not distinct from themselves before and after the contract modification occurred; however, they are distinct from the terminated oncology target performance obligations. As a result, the Company allocated the unrecognized transaction price to the three remaining performance obligations based on their relative estimated SSP and calculated a cumulative catch-up adjustment of $0.8 million which was recognized as collaboration revenue during the three months ended June 30, 2024.

For the three and six months ended June 30, 2024, the Company recognized collaboration revenue related to the Sanofi Agreement of $1.3 million and $1.8 million, respectively, and $0.4 million and $1.0 million for the three and six months ended June 30, 2023. As of June 30, 2024 and December 31, 2023, $145.1 million and $146.8 million were recorded as deferred revenue related to the Sanofi Agreement, respectively, of which $2.0 million and $3.8 million, respectively, were classified as current, on the condensed consolidated balance sheets. The deferred revenue is expected to be recognized over the research and development period of the programs through the completion of Phase 1 clinical trials.

Contract Balances from Customer Contract

The timing of revenue recognition, billings and cash collections results in contract assets and contract liabilities on the condensed consolidated balance sheets. The Company recognizes license and development receivables based on billed services, which are settled upon reimbursement. When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded. Contract liabilities are recognized as revenue after control of the goods or services is transferred to the customer and all revenue recognition criteria have been met.

The following tables present changes in the Company’s customer contract liabilities for the periods presented (in thousands):


Six Months Ended June 30, 2024	December 31, 2023		Additions		Deductions			June 30, 2024
Contract liabilities:
Deferred revenue	$	146,801	$	—	$	(1,751	)	$	145,050


Six Months Ended June 30, 2023	December 31, 2022		Additions		Deductions			June 30, 2023
Contract liabilities:
Deferred revenue	$	148,931	$	—	$	(970	)	$	147,961

The Company had no customer contract assets during the three and six months ended June 30, 2024 and 2023.

Organization	6 Months Ended
Organization	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Note 1. Organization Description of the Business IGM Biosciences, Inc. (the Company) was incorporated in the state of Delaware in August 1993 under the name Palingen, Inc. and the name was subsequently changed to IGM Biosciences, Inc. in 2010. The Company’s headquarters are in Mountain View, California. IGM Biosciences, Inc. is a biotechnology company engaged in the development of IgM antibody therapeutics for the treatment of cancer and autoimmune and inflammatory diseases. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP), as defined by the Financial Accounting Standards Board (FASB), and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments which are necessary for a fair statement of the Company’s financial information. The interim results of operations for the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024 or for any other interim period or for any other future year. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The accompanying interim unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2023, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 7, 2024. Liquidity The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $919.0 million as of June 30, 2024. As of June 30, 2024, the Company had cash, cash equivalents, and marketable securities of $256.4 million. Management believes that the existing financial resources are sufficient to continue operating activities at least one year past the issuance date of these condensed consolidated financial statements. The Company has historically financed its operations primarily through the sale of common stock and pre-funded warrants in its public offerings and private placement, the sale of convertible preferred stock and issuance of unsecured promissory notes in private placements, and funding received from our collaboration partners. To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any product revenue since inception. Management expects operating losses to continue and increase for the foreseeable future, as the Company progresses its planned research and development activities for its product candidates. The Company’s prospects are subject to risks, expenses and uncertainties frequently encountered by companies in the biotechnology industry as discussed below. While the Company has been able to raise multiple rounds of financing, there can be no assurance that in the event the Company requires additional financing, such financing will be available on terms which are favorable or at all. Failure to raise sufficient capital when needed or generate sufficient cash flow from operations would impact the ability to pursue business strategies and could require the Company to delay, scale back or discontinue one or more product development programs, or other aspects of the Company's business objectives.

Accrued Liabilities (Tables)

6 Months Ended

Jun. 30, 2024

Balance Sheet Related Disclosures [Abstract]

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	June 30,		December 31,
	2024		2023
Accrued research and development materials and services	$	16,740	$	14,625
Accrued professional services		1,381		3,147
Accrued compensation		7,249		13,527
Other		1,091		245
Total accrued liabilities	$	26,461	$	31,544

Stockholders' Equity - Pre-Funded Warrants - Additional Information (Details) - $ / shares		3 Months Ended
	Dec. 31, 2020	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023
Class of Warrant or Right [Line Items]
Maximum allowed holding percentage of shares after exercise of warrants	9.99%
Maximum allowed combined voting percentage of shares after exercise of warrants	9.99%
Maximum allowed percentage of pre-funded warrants to exercise	19.99%
Minimum notice term to increase or decrease the holding percentage of pre-funded warrants	61 days
Common Stock
Class of Warrant or Right [Line Items]
Issuance of common stock, shares		96,550	156,439	81,136	64,863
Underwritten Public Offering \| Pre-funded Warrant
Class of Warrant or Right [Line Items]
Warrants to purchase an additional shares of common stock	1,334,332
Pre-funded warrant, exercise price	$ 0.01

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ (47,902)	$ (64,423)	$ (97,718)	$ (123,732)
Other comprehensive income (loss):
Unrealized (loss) gain on marketable securities	(67)	(105)	(346)	249
Comprehensive loss	$ (47,969)	$ (64,528)	$ (98,064)	$ (123,483)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-60B

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-7

Reference 34: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1A

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1B

Reference 37: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Fair Value Measurement - Summary of Investments Measured and Recognized at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 252,267	$ 331,714
Gross Unrealized Gains	1	228
Gross Unrealized Losses	(196)	(77)
Fair Value	252,072	331,865
Financial Assets Included Within Cash and Cash Equivalents \| Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	28,413	21,458
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	0	0
Included within cash and cash equivalents, Fair Value	28,413	21,458
Financial Assets Included Within Cash and Cash Equivalents \| U.S. Treasury Securities \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost		25,896
Included within cash and cash equivalents, Gross Unrealized Gains		2
Included within cash and cash equivalents, Gross Unrealized Losses		0
Included within cash and cash equivalents, Fair Value		25,898
Financial Assets Included Within Cash and Cash Equivalents \| Commercial Paper \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	26,875	54,427
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	(14)	(27)
Included within cash and cash equivalents, Fair Value	26,861	54,400
Financial Assets Included Within Cash and Cash Equivalents \| U.S. Government Agency Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	7,391	4,951
Included within cash and cash equivalents, Gross Unrealized Gains	0	1
Included within cash and cash equivalents, Gross Unrealized Losses	0	0
Included within cash and cash equivalents, Fair Value	7,391	4,952
Financial Assets Included Within Marketable Securities [Member] \| U.S. Treasury Securities \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	133,549	182,289
Included within cash and cash equivalents, Gross Unrealized Gains	1	214
Included within cash and cash equivalents, Gross Unrealized Losses	(119)	(14)
Included within cash and cash equivalents, Fair Value	133,431	182,489
Financial Assets Included Within Marketable Securities [Member] \| Corporate Bonds \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	17,286	13,986
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	(27)	(8)
Included within cash and cash equivalents, Fair Value	17,259	13,978
Financial Assets Included Within Marketable Securities [Member] \| Commercial Paper \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	24,549	20,216
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	(17)	(17)
Included within cash and cash equivalents, Fair Value	24,532	20,199
Financial Assets Included Within Marketable Securities [Member] \| U.S. Government Agency Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Included within cash and cash equivalents, Amortized Cost	14,204	8,491
Included within cash and cash equivalents, Gross Unrealized Gains	0	11
Included within cash and cash equivalents, Gross Unrealized Losses	(19)	(11)
Included within cash and cash equivalents, Fair Value	$ 14,185	$ 8,491

Sanofi Agreement (Additional Information) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	May 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue	$ 145,050	$ 147,961	$ 145,050	$ 147,961	$ 146,801	$ 148,931
Contract asset	0	0	0	0
Sanofi Agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue	145,100		145,100		146,800
Deferred revenue, current	2,000		2,000		$ 3,800
Revenues	1,300	$ 400	1,800	$ 1,000
Adjustment of collaboration revenue	$ 800
Revenue transaction price			150,000
Upfront payment received							$ 150,000
Development And Regulatory Milestones Exchange			$ 1,065,000

Net Loss Per Share Attributable to Common Stockholders - Summary of Potentially Dilutive Securities Not Included in the Diluted Per Share Calculations (Details) - shares	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	9,319,517	8,408,284
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	7,525,626	7,390,547
Estimated Shares Issuable Under Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	86,292	59,616
Unvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	1,707,599	958,121

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (47,902)	$ (49,816)	$ (64,423)	$ (59,309)	$ (97,718)	$ (123,732)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Restructuring Charges

6 Months Ended

Jun. 30, 2024

Restructuring and Related Activities [Abstract]

Restructuring Charges

Note 9. Restructuring Charges

On December 5, 2023, the Company committed to a strategic refocusing (Strategic Refocusing) and suspended clinical development activities for certain product candidates in several indications and reduced its workforce by approximately 22%, with headcount reductions substantially completed by December 31, 2023 and fully completed by March 31, 2024.

In connection with the Strategic Refocusing, the Company recognized no restructuring charges and $0.2 million in restructuring charges during the three and six months ended June 30, 2024, respectively. The Company recognized $1.8 million in restructuring charges during the three months ended December 31, 2023, which were primarily related to severance and one-time termination payments of $3.7 million and partially offset by a $1.9 million reversal of previously recognized non-cash stock-based compensation expense. All severance and one-time termination payments had been paid by March 31, 2024.

The following table summarizes the changes in the Company's accrued restructuring balance (in thousands):


	Beginning Balance December 31, 2023		Charges		Payments			Ending Balance June 30, 2024
Accrued severance	$	2,397	$	—	$	(2,397	)	$	—
Accrued contract termination costs		—		107		(107	)		—
Total accrued restructuring liability	$	2,397	$	107	$	(2,504	)	$	—

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Collaboration revenue	$ 1,254	$ 448	$ 1,751	$ 970
Operating expenses:
Research and development	41,962	55,673	85,777	106,567
General and administrative	10,649	12,983	21,187	25,985
Total operating expenses	52,611	68,656	106,964	132,552
Loss from operations	(51,357)	(68,208)	(105,213)	(131,582)
Other income (expense):
Interest income	3,455	3,894	7,495	8,066
Other expense	0	0	0	(20)
Total other income (expense)	3,455	3,894	7,495	8,046
Loss before income tax expense	(47,902)	(64,314)	(97,718)	(123,536)
Income tax expense	0	(109)	0	(196)
Net loss	$ (47,902)	$ (64,423)	$ (97,718)	$ (123,732)
Net loss per share, basic	$ (0.79)	$ (1.43)	$ (1.62)	$ (2.76)
Net loss per share, diluted	$ (0.79)	$ (1.43)	$ (1.62)	$ (2.76)
Weighted-average common shares outstanding, basic	60,434,161	45,122,900	60,274,285	44,796,644
Weighted-average common shares outstanding, diluted	60,434,161	45,122,900	60,274,285	44,796,644

Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Balance Sheet Related Disclosures [Abstract]
Accrued research and development materials and services	$ 16,740	$ 14,625
Accrued professional services	1,381	3,147
Accrued compensation	7,249	13,527
Other	1,091	245
Total accrued liabilities	$ 26,461	$ 31,544

License Agreements

6 Months Ended

Jun. 30, 2024

License Agreement [Abstract]

License Agreements

Note 5. License Agreements

The Company enters into arrangements to in-license research and development technology rights with third parties relating to its clinical and pre-clinical programs and product candidates. These arrangements may include non-refundable, upfront payments, payments for options to acquire additional rights relating to its product candidates, as well as contingent obligations for potential development, regulatory and commercial performance milestone payments, and royalty payments. The Company’s obligation to make payments for contingent obligations is contingent upon the respective milestones being achieved as well as its continued involvement in the programs and/or the lack of any adverse events which could cause the discontinuance of the programs. The activities under these license agreements are performed with no guarantee of either technological or commercial success.

During the three and six months ended June 30, 2024, the Company recorded no license fees and $0.6 million, respectively, of research and development expenses in our condensed consolidated statements of operations related to license agreements, and $0.2 million and $0.5 million, for the three and six months ended June 30, 2023.

As of June 30, 2024, the Company’s license agreements for technologies optioned by the Company, including the Medivir agreement described below, included potential future payments for development, regulatory, and sales milestones totaling approximately $361.9 million plus royalties on net sales that range from single digits to mid-teens. No milestones were achieved or deemed probable as of June 30, 2024.

Medivir Agreement

In January 2021, the Company entered into an exclusive license agreement with Medivir AB (Medivir) through which the Company received global, exclusive development and commercialization rights for birinapant, a clinical-stage Second Mitochondrial-derived Activator of Caspases (SMAC) mimetic. Under the terms of the agreement, the Company made an upfront payment of $1.0 million upon signing the agreement, and made an additional $1.5 million payment in November 2021 due to the Company's initiation of a Phase 1 clinical trial of aplitabart in combination with birinapant. Under the terms of the agreement, should birinapant be successfully developed and approved, the Company would be obligated to make additional milestone payments up to a total of approximately $348.5 million, plus tiered royalties from the mid-single digits up to mid-teens on net sales. No milestones were achieved or deemed probable as of June 30, 2024.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

Note 8. Stock-Based Compensation

The 2018 Omnibus Incentive Plan (the 2018 Plan) provides for an increase in the number of shares reserved for issuance on the first day of each fiscal year equal to the least of (i) 8,768,800 shares, (ii) 4% of the Company’s common stock and non-voting common stock outstanding at December 31 of the immediately preceding year, or (iii) such number of shares as determined by the Company’s Board of Directors. As a result of this provision, on January 1, 2024 and 2023, an additional 2,347,245 and 1,723,292 shares, respectively, became available for issuance under the 2018 Plan. As of June 30, 2024, the 2018 Plan had 3,623,814 shares of common stock available for future issuance.

Total stock-based compensation expense related to the Company’s equity incentive plan and employee stock purchase plan was recorded in the condensed consolidated statements of operations as follows (in thousands):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
Research and development	$	4,807	$	8,248	$	9,169	$	14,687
General and administrative		3,621		6,061		7,181		10,669
Total stock-based compensation expense	$	8,428	$	14,309	$	16,350	$	25,356

The following table summarizes the Company's stock awards granted for each of the periods indicated:


	Three Months Ended June 30,								Six Months Ended June 30,
	2024				2023				2024				2023
	Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value
Stock options		29,805	$	7.44		1,475,238	$	9.92		1,552,298	$	7.82		1,726,338	$	10.92
Restricted stock units		35,474	$	8.53		697,236	$	12.43		1,400,817	$	9.89		716,450	$	12.63

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) Segment	Jun. 30, 2023 USD ($)
Summary of Significant Accounting Policies [Line Items]
Number of reportable segments \| Segment			1
Number of operating segment \| Segment			1
Impairment of long-lived assets \| $	$ 0	$ 0	$ 0	$ 0
Interest or penalties charged in relation to unrecognized tax benefits \| $			$ 0
Minimum
Summary of Significant Accounting Policies [Line Items]
Property and equipment estimated useful life	3 years		3 years
Maximum
Summary of Significant Accounting Policies [Line Items]
Property and equipment estimated useful life	5 years		5 years

Sanofi Agreement (Tables)

6 Months Ended

Jun. 30, 2024

Sanofi Agreement [Abstract]

Schedule of contract liabilities for the periods

The following tables present changes in the Company’s customer contract liabilities for the periods presented (in thousands):


Six Months Ended June 30, 2024	December 31, 2023		Additions		Deductions			June 30, 2024
Contract liabilities:
Deferred revenue	$	146,801	$	—	$	(1,751	)	$	145,050


Six Months Ended June 30, 2023	December 31, 2022		Additions		Deductions			June 30, 2023
Contract liabilities:
Deferred revenue	$	148,931	$	—	$	(970	)	$	147,961

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - 2010 Plan, 2018 Plan and ESPP - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	$ 8,428	$ 14,309	$ 16,350	$ 25,356
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	4,807	8,248	9,169	14,687
General And Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	$ 3,621	$ 6,061	$ 7,181	$ 10,669

Stockholders' Equity - Additional Information (Details)	6 Months Ended	12 Months Ended
Stockholders' Equity - Additional Information (Details)	Jun. 30, 2024 USD ($) Vote $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Class Of Stock [Line Items]
Common stock, shares authorized	120,000,000	120,000,000
Preferred stock, shares authorized	200,000,000	200,000,000
Preferred stock, par value \| $ / shares	$ 0.01	$ 0.01
Common stock, voting rights	Each share of common stock (excluding non-voting common stock) is entitled to one vote.
Number of common stock voting rights held \| Vote	1
Common stock, dividends declared \| $	$ 0	$ 0
Non-voting Common Stock
Class Of Stock [Line Items]
Common stock, shares authorized	200,000,000	200,000,000
Common stock, par value \| $ / shares	$ 0.01	$ 0.01
Common Stock, Shares, Issued	25,386,983	25,500,383

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2024

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
Research and development	$	4,807	$	8,248	$	9,169	$	14,687
General and administrative		3,621		6,061		7,181		10,669
Total stock-based compensation expense	$	8,428	$	14,309	$	16,350	$	25,356

Summary of Company's stock awards granted

The following table summarizes the Company's stock awards granted for each of the periods indicated:


	Three Months Ended June 30,								Six Months Ended June 30,
	2024				2023				2024				2023
	Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value
Stock options		29,805	$	7.44		1,475,238	$	9.92		1,552,298	$	7.82		1,726,338	$	10.92
Restricted stock units		35,474	$	8.53		697,236	$	12.43		1,400,817	$	9.89		716,450	$	12.63

Subsequent Events (Additional Information) (Details) - Subsequent Event - Restricted Stock Units	Jul. 19, 2024 $ / shares shares
Subsequent Event [Line Items]
Stock Option, Exercise Price \| $ / shares	$ 17.7
Vesting Unit Rate	50.00%
Issuance of common stock, shares	657,427
Common Stock, Options, Cancelled	1,583,305
Maximum
Subsequent Event [Line Items]
Vesting period	3 years
Minimum
Subsequent Event [Line Items]
Vesting period	2 years

Organization - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Subsidiary Sale Of Stock [Line Items]
Accumulated deficit	$ (918,960)	$ (821,242)
Cash, and investments	$ 256,400

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Fair Value Measurement - Summary of Available-for-sale Securities Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	$ 198,293	$ 121,485
Less than 12 months, unrealized losses	(195)	(77)
Greater than 12 months, fair value	1,497	0
Greater than 12 months, unrealized losses	(1)	0
Total, fair value	199,790	121,485
Total, unrealized losses	(196)	(77)
U.S. Treasury Securities
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	108,065	28,137
Less than 12 months, unrealized losses	(118)	(14)
Greater than 12 months, fair value	1,497	0
Greater than 12 months, unrealized losses	(1)	0
Total, fair value	109,562	28,137
Total, unrealized losses	(119)	(14)
Corporate Bonds
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	17,259	13,978
Less than 12 months, unrealized losses	(27)	(8)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	17,259	13,978
Total, unrealized losses	(27)	(8)
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	51,393	74,599
Less than 12 months, unrealized losses	(31)	(44)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	51,393	74,599
Total, unrealized losses	(31)	(44)
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	21,576	4,771
Less than 12 months, unrealized losses	(19)	(11)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	21,576	4,771
Total, unrealized losses	$ (19)	$ (11)

Restructuring Charges (Tables)

6 Months Ended

Jun. 30, 2024

Restructuring and Related Activities [Abstract]

Summary of Changes in Company's Accrued Restructuring Balance

The following table summarizes the changes in the Company's accrued restructuring balance (in thousands):


	Beginning Balance December 31, 2023		Charges		Payments			Ending Balance June 30, 2024
Accrued severance	$	2,397	$	—	$	(2,397	)	$	—
Accrued contract termination costs		—		107		(107	)		—
Total accrued restructuring liability	$	2,397	$	107	$	(2,504	)	$	—

Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2024

Fair Value Disclosures [Abstract]

Summary of Investments Measured and Recognized at Fair Value

The following tables set forth the fair value of the Company’s financial assets, which consist of cash equivalents and marketable securities measured and recognized at fair value (in thousands):


		June 30, 2024
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	28,413	$	—	$	—		$	28,413
U.S. government agency securities	Level 2		7,391		—		—			7,391
Commercial paper	Level 2		26,875		—		(14	)		26,861
Marketable securities:
U.S. treasury securities	Level 1		133,549		1		(119	)		133,431
Corporate bonds	Level 2		17,286		—		(27	)		17,259
Commercial paper	Level 2		24,549		—		(17	)		24,532
U.S. government agency securities	Level 2		14,204		—		(19	)		14,185
Total		$	252,267	$	1	$	(196	)	$	252,072


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	21,458	$	—	$	—		$	21,458
U.S. treasury securities	Level 1		25,896		2		—			25,898
Commercial paper	Level 2		54,427		—		(27	)		54,400
U.S. government agency securities	Level 2		4,951		1		—			4,952
Marketable securities:
U.S. treasury securities	Level 1		182,289		214		(14	)		182,489
Corporate bonds	Level 2		13,986		—		(8	)		13,978
Commercial paper	Level 2		20,216		—		(17	)		20,199
U.S. government agency securities	Level 2		8,491		11		(11	)		8,491
Total		$	331,714	$	228	$	(77	)	$	331,865

Schedule of Unrealized Loss on Marketable Securities

The following table summarizes the available-for-sale securities in an unrealized loss position for which an allowance for credit losses has not been recorded as of June 30, 2024 and December 31, 2023, aggregated by major security type and length of time in a continuous unrealized loss position:


	June 30, 2024
	Less than 12 months					Greater than 12 months					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
U.S. treasury securities	$	108,065	$	(118	)	$	1,497	$	(1	)	$	109,562	$	(119	)
Corporate bonds		17,259		(27	)		—		—			17,259		(27	)
Commercial paper		51,393		(31	)		—		—			51,393		(31	)
U.S. government agency securities		21,576		(19	)		—		—			21,576		(19	)
Total	$	198,293	$	(195	)	$	1,497	$	(1	)	$	199,790	$	(196	)


	December 31, 2023
	Less than 12 months					Greater than 12 months				Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. treasury securities	$	28,137	$	(14	)	$	—	$	—	$	28,137	$	(14	)
Corporate bonds		13,978		(8	)		—		—		13,978		(8	)
Commercial paper		74,599		(44	)		—		—		74,599		(44	)
U.S. government agency securities		4,771		(11	)		—		—		4,771		(11	)
Total	$	121,485	$	(77	)	$	—	$	—	$	121,485	$	(77	)

Summary of Contractual Maturities of Marketable Securities

The following table summarizes the contractual maturities of the Company’s cash equivalents and marketable securities as of June 30, 2024 and December 31, 2023 at estimated fair value (in thousands):


	June 30,		December 31,
	2024		2023
Due in less than one year	$	239,955	$	312,554
Due in more than one year		12,117		19,311
Total	$	252,072	$	331,865

Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2024

Stockholders' Equity Note [Abstract]

Schedule of Number of Common Stock Reserved for Future Issuance

The Company had reserved common stock, on an as-converted basis, for future issuance as follows:


	June 30,		December 31,
	2024		2023
Stock options, issued and outstanding		7,525,626		6,766,340
Restricted stock units		1,707,599		658,792
Stock options and restricted stock units, future issuance		3,623,814		3,536,312
Employee stock purchase plan, available for future grants		1,821,195		1,376,988
Pre-funded warrants		1,334,332		1,334,332
Total		16,012,566		13,672,764

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Common Stock Non-voting Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Dec. 31, 2022	$ 287,263	$ 294	$ 137	$ 862,359	$ (701)	$ (574,826)
Balance, shares at Dec. 31, 2022		29,394,436	13,687,883
Exercise of stock options	75			75
Exercise of stock options, shares		40,774
Issuance of common stock for vested restricted stock units		$ 1		(1)
Issuance of common stock for vested restricted stock units, share		64,863
Unrealized (loss) gain on marketable securities	354				354
Stock-based compensation expense	11,047			11,047
Net Income (Loss)	(59,309)					(59,309)
Balance at Mar. 31, 2023	239,430	$ 295	$ 137	873,480	(347)	(634,135)
Balance, shares at Mar. 31, 2023		29,500,073	13,687,883
Balance at Dec. 31, 2022	287,263	$ 294	$ 137	862,359	(701)	(574,826)
Balance, shares at Dec. 31, 2022		29,394,436	13,687,883
Unrealized (loss) gain on marketable securities	249
Net Income (Loss)	(123,732)
Balance at Jun. 30, 2023	258,607	$ 329	$ 199	957,089	(452)	(698,558)
Balance, shares at Jun. 30, 2023		32,864,056	19,875,383
Balance at Mar. 31, 2023	239,430	$ 295	$ 137	873,480	(347)	(634,135)
Balance, shares at Mar. 31, 2023		29,500,073	13,687,883
Exercise of stock options	14			14
Exercise of stock options, shares		10,788
Issuance of common stock for vested restricted stock units		$ 1		(1)
Issuance of common stock for vested restricted stock units, share		81,136
Issuance of common stock in connection with public offering and private placement, net of offering costs, Shares		3,187,500	6,187,500
Issuance of common stock in connection with public offering and private placement, net of offering costs	68,391	$ 32	$ 62	68,297
Purchases under employee stock purchase plan		84,559
Purchases under employee stock purchase plan, value	991	$ 1		990
Unrealized (loss) gain on marketable securities	(105)				(105)
Stock-based compensation expense	14,309			14,309
Net Income (Loss)	(64,423)					(64,423)
Balance at Jun. 30, 2023	258,607	$ 329	$ 199	957,089	(452)	(698,558)
Balance, shares at Jun. 30, 2023		32,864,056	19,875,383
Balance at Dec. 31, 2023	203,234	$ 331	$ 255	1,023,739	151	(821,242)
Balance, shares at Dec. 31, 2023		33,180,749	25,500,383
Conversion of non-voting common stock into voting common stock		$ 1	$ (1)
Conversion of non-voting common stock into voting common stock, shares		113,400	(113,400)
Exercise of stock options, net of shares withheld for taxes and exercise costs	192	$ 1		191
Exercise of stock options, net of shares withheld for taxes and exercise costs		113,314
Issuance of common stock for vested restricted stock units		$ 2		(2)
Issuance of common stock for vested restricted stock units, share		156,439
Unrealized (loss) gain on marketable securities	(279)				(279)
Stock-based compensation expense	7,922			7,922
Net Income (Loss)	(49,816)					(49,816)
Balance at Mar. 31, 2024	161,253	$ 335	$ 254	1,031,850	(128)	(871,058)
Balance, shares at Mar. 31, 2024		33,563,902	25,386,983
Balance at Dec. 31, 2023	203,234	$ 331	$ 255	1,023,739	151	(821,242)
Balance, shares at Dec. 31, 2023		33,180,749	25,500,383
Unrealized (loss) gain on marketable securities	(346)
Net Income (Loss)	(97,718)
Balance at Jun. 30, 2024	122,358	$ 338	$ 254	1,040,921	(195)	(918,960)
Balance, shares at Jun. 30, 2024		33,852,584	25,386,983
Balance at Mar. 31, 2024	161,253	$ 335	$ 254	1,031,850	(128)	(871,058)
Balance, shares at Mar. 31, 2024		33,563,902	25,386,983
Exercise of stock options, net of shares withheld for taxes and exercise costs	64	$ 1		63
Exercise of stock options, net of shares withheld for taxes and exercise costs		76,339
Issuance of common stock for vested restricted stock units		$ 1		(1)
Issuance of common stock for vested restricted stock units, share		96,550
Purchases under employee stock purchase plan		115,793
Purchases under employee stock purchase plan, value	582	$ 1		581
Unrealized (loss) gain on marketable securities	(67)				(67)
Stock-based compensation expense	8,428			8,428
Net Income (Loss)	(47,902)					(47,902)
Balance at Jun. 30, 2024	$ 122,358	$ 338	$ 254	$ 1,040,921	$ (195)	$ (918,960)
Balance, shares at Jun. 30, 2024		33,852,584	25,386,983

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	200,000,000	200,000,000
Preferred Stock, shares Issued	0	0
Preferred Stock, shares outstanding	0	0
Common stock, shares authorized	120,000,000	120,000,000
Common Stock Class Undefined
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	33,852,584	33,180,749
Common stock, shares outstanding	33,852,584	33,180,749
Non-voting Common Stock
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	25,386,983	25,500,383
Common stock, shares outstanding	25,386,983	25,500,383

Net Loss Per Share Attributable to Common Stockholders

6 Months Ended

Jun. 30, 2024

Earnings Per Share [Abstract]

Net Loss Per Share Attributable to Common Stockholders

Note 10. Net Loss Per Share Attributable to Common Stockholders

Basic and diluted net loss per share is computed by dividing net loss by the weighted-average number of common stock and pre-funded warrants outstanding for the period. Shares of common stock into which the pre-funded warrants may be exercised are

considered outstanding for the purposes of computing net loss per share because the shares may be issued for little or no consideration, are fully vested, and are exercisable after the original issuance date. For periods in which the Company generated a net loss, the Company does not include the potential impact of dilutive securities in diluted net loss per share, as the impact of these items is anti-dilutive.

The following equity instruments were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented:


	June 30,
	2024		2023
Stock options		7,525,626		7,390,547
Estimated shares issuable under the employee stock purchase plan		86,292		59,616
Unvested restricted stock units		1,707,599		958,121
Total		9,319,517		8,408,284

Stockholders' Equity

6 Months Ended

Jun. 30, 2024

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Note 6. Stockholders' Equity

Common Stock and Non-Voting Common Stock

As of June 30, 2024 and December 31, 2023, the Company’s certificate of incorporation authorized the Company to issue 1,200,000,00 shares of common stock (including 200,000,000 shares of non-voting common stock) and 200,000,000 shares of preferred stock, at a par value of $0.01 per share. Each share of common stock (excluding non-voting common stock) is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Company’s Board of Directors, subject to prior rights of the preferred stockholders. As of June 30, 2024 and December 31, 2023, no dividends have been declared.

The Company had reserved common stock, on an as-converted basis, for future issuance as follows:


	June 30,		December 31,
	2024		2023
Stock options, issued and outstanding		7,525,626		6,766,340
Restricted stock units		1,707,599		658,792
Stock options and restricted stock units, future issuance		3,623,814		3,536,312
Employee stock purchase plan, available for future grants		1,821,195		1,376,988
Pre-funded warrants		1,334,332		1,334,332
Total		16,012,566		13,672,764

Pre-Funded Warrants

In December 2020, the Company issued pre-funded warrants to purchase up to 1,334,332 shares of common stock in an underwritten public offering at the offering price of the common stock, less the $0.01 per share exercise price of each warrant and were issued to two separate related party affiliates. The pre-funded warrants were recorded as a component of stockholders’ equity within additional paid-in-capital and will expire on the date any such warrant is exercised in full.

Subject to applicable law, upon exercise of a pre-funded warrant, a holder may elect to receive the same number of shares of non-voting common stock as the shares of common stock for which the pre-funded warrant is exercisable, provided that (i) at the time of such election there is a sufficient number of authorized but unissued and otherwise unreserved shares of non-voting common stock and (ii) the Company consents to such election.

The outstanding pre-funded warrants to purchase shares of common stock are exercisable at any time after their original issuance. However, the Company may not affect the exercise of any pre-funded warrants, and a holder will not be entitled to exercise any portion of any pre-funded warrants that, upon giving effect to such exercise, would cause: (i) the aggregate number of shares of the Company’s common stock beneficially owned by such holder (together with its affiliates) to exceed 9.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to the exercise; or (ii) the combined voting power of the Company’s securities beneficially owned by such holder (together with its affiliates) to exceed 9.99% of the combined voting power of all of the Company’s securities outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. However, any holder of a pre-funded warrant may increase or decrease such percentage to any other percentage not in excess of 19.99% upon at least 61 days’ prior notice from the holder to the Company. As of June 30, 2024, no shares underlying the pre-funded warrants had been exercised. All of the outstanding pre-funded warrants are included in the weighted-average number of shares of common stock used to calculate basic net loss per share attributable to common stockholders (see Note 10 – Net Loss Per Share Attributable to Common Stockholders).

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 66,974	$ 112,520
Restricted cash	289	592
Marketable securities	189,407	225,157
Prepaid expenses and other current assets	9,348	9,328
Total current assets	266,018	347,597
Property, plant and equipment, net	36,012	38,232
Operating lease right-of-use assets	33,040	35,773
Other non-current assets	1,431	1,809
Total assets	336,501	423,411
Current liabilities:
Accounts payable	3,259	1,326
Accrued liabilities	26,461	31,544
Lease liabilities	5,937	5,834
Deferred revenue	1,998	3,777
Total current liabilities	37,655	42,481
Lease liabilities, non-current	33,436	34,672
Deferred revenue, non-current	143,052	143,024
Total liabilities	214,143	220,177
Commitments and contingencies (Note 5)
Stockholders' equity:
Preferred stock, $0.01 par value; 200,000,000 shares authorized as ofJune 30, 2024 and December 31, 2023; no shares issued and outstanding as of june 30, 2024 and December 31, 2023	0	0
Additional paid-in-capital	1,040,921	1,023,739
Accumulated other comprehensive (loss) income	(195)	151
Accumulated deficit	(918,960)	(821,242)
Total stockholders' equity	122,358	203,234
Total liabilities and stockholders' equity	336,501	423,411
Common Stock Class Undefined
Stockholders' equity:
Common stock, value	338	331
Non-voting Common Stock
Stockholders' equity:
Common stock, value	$ 254	$ 255

Related Party Transactions - Additional Information (Details) - Common Stock - shares	3 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023
Related Party Transaction [Line Items]
Issuance of common stock, shares	96,550	156,439	81,136	64,863
Stock Issued During Period, Shares, Conversion of Convertible Securities		113,400
Non-voting Common Stock
Related Party Transaction [Line Items]
Stock Issued During Period, Shares, Conversion of Convertible Securities		(113,400)

Restructuring Charges - Summary of Changes in Company's Accrued Restructuring Balance (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Restructuring Cost and Reserve [Line Items]
Charges	$ 0	$ 200	$ 1,800
Accrued severance [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance		2,397
Charges		0
Payments		(2,397)
Ending Balance	0	0	2,397
Accrued contract termination costs [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance		0
Charges		107
Payments		(107)
Ending Balance	0	0	0
Total accrued restructuring liability
Restructuring Cost and Reserve [Line Items]
Beginning Balance		2,397
Charges		107
Payments		(2,504)
Ending Balance	$ 0	$ 0	$ 2,397

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Fair Value Measurement

6 Months Ended

Jun. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurement

Note 3. Fair Value Measurement

The Company measures and reports certain financial instruments as assets and liabilities at fair value on a recurring basis. The following tables set forth the fair value of the Company’s financial assets, which consist of cash equivalents and marketable securities measured and recognized at fair value (in thousands):


		June 30, 2024
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	28,413	$	—	$	—		$	28,413
U.S. government agency securities	Level 2		7,391		—		—			7,391
Commercial paper	Level 2		26,875		—		(14	)		26,861
Marketable securities:
U.S. treasury securities	Level 1		133,549		1		(119	)		133,431
Corporate bonds	Level 2		17,286		—		(27	)		17,259
Commercial paper	Level 2		24,549		—		(17	)		24,532
U.S. government agency securities	Level 2		14,204		—		(19	)		14,185
Total		$	252,267	$	1	$	(196	)	$	252,072


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	21,458	$	—	$	—		$	21,458
U.S. treasury securities	Level 1		25,896		2		—			25,898
Commercial paper	Level 2		54,427		—		(27	)		54,400
U.S. government agency securities	Level 2		4,951		1		—			4,952
Marketable securities:
U.S. treasury securities	Level 1		182,289		214		(14	)		182,489
Corporate bonds	Level 2		13,986		—		(8	)		13,978
Commercial paper	Level 2		20,216		—		(17	)		20,199
U.S. government agency securities	Level 2		8,491		11		(11	)		8,491
Total		$	331,714	$	228	$	(77	)	$	331,865

The Company evaluates transfers between levels at the end of each reporting period. There were no transfers between Levels 1, 2 and 3 during the three and six months ended June 30, 2024 and 2023. As of June 30, 2024 and December 31, 2023, there were no financial instruments classified as Level 3.


	June 30, 2024
	Less than 12 months					Greater than 12 months					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
U.S. treasury securities	$	108,065	$	(118	)	$	1,497	$	(1	)	$	109,562	$	(119	)
Corporate bonds		17,259		(27	)		—		—			17,259		(27	)
Commercial paper		51,393		(31	)		—		—			51,393		(31	)
U.S. government agency securities		21,576		(19	)		—		—			21,576		(19	)
Total	$	198,293	$	(195	)	$	1,497	$	(1	)	$	199,790	$	(196	)


	December 31, 2023
	Less than 12 months					Greater than 12 months				Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. treasury securities	$	28,137	$	(14	)	$	—	$	—	$	28,137	$	(14	)
Corporate bonds		13,978		(8	)		—		—		13,978		(8	)
Commercial paper		74,599		(44	)		—		—		74,599		(44	)
U.S. government agency securities		4,771		(11	)		—		—		4,771		(11	)
Total	$	121,485	$	(77	)	$	—	$	—	$	121,485	$	(77	)

As of June 30, 2024 and December 31, 2023, the Company held 55 and 35 debt securities, respectively, with an unrealized loss position. The Company evaluated its securities for credit losses and considered the decline in market value to be primarily attributable to current economic and market conditions and not to a credit loss or other factors. Additionally, the Company does not intend to sell the securities in an unrealized loss position and does not expect it will be required to sell the securities before recovery of the unamortized cost basis. As of June 30, 2024 and December 31, 2023, an allowance for credit losses has not been recognized. Given the Company's intent and ability to hold such securities until recovery, and the lack of significant change in credit risk of these investments, it does not consider these marketable securities impaired as of June 30, 2024 and December 31, 2023.

There were no realized gains or losses on marketable securities for the three and six months ended June 30, 2024 and 2023. Interest on marketable securities is included in interest income. As of June 30, 2024 and December 31, 2023, the Company had accrued interest receivable of $0.9 million and $0.8 million, respectively, which was included in prepaid expenses and other current assets on the condensed consolidated balance sheets.


	June 30,		December 31,
	2024		2023
Due in less than one year	$	239,955	$	312,554
Due in more than one year		12,117		19,311
Total	$	252,072	$	331,865

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

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-Section 55
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
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-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Jun. 30, 2024	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Julie Hambleton, M.D [Member]
Trading Arrangements, by Individual
Arrangement Duration		361 days

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2024
Accounting Policies [Abstract]
Description of the Business	Description of the Business IGM Biosciences, Inc. (the Company) was incorporated in the state of Delaware in August 1993 under the name Palingen, Inc. and the name was subsequently changed to IGM Biosciences, Inc. in 2010. The Company’s headquarters are in Mountain View, California. IGM Biosciences, Inc. is a biotechnology company engaged in the development of IgM antibody therapeutics for the treatment of cancer and autoimmune and inflammatory diseases.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP), as defined by the Financial Accounting Standards Board (FASB), and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments which are necessary for a fair statement of the Company’s financial information. The interim results of operations for the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024 or for any other interim period or for any other future year. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The accompanying interim unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2023, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 7, 2024.
Liquidity	Liquidity The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $919.0 million as of June 30, 2024. As of June 30, 2024, the Company had cash, cash equivalents, and marketable securities of $256.4 million. Management believes that the existing financial resources are sufficient to continue operating activities at least one year past the issuance date of these condensed consolidated financial statements. The Company has historically financed its operations primarily through the sale of common stock and pre-funded warrants in its public offerings and private placement, the sale of convertible preferred stock and issuance of unsecured promissory notes in private placements, and funding received from our collaboration partners. To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any product revenue since inception. Management expects operating losses to continue and increase for the foreseeable future, as the Company progresses its planned research and development activities for its product candidates. The Company’s prospects are subject to risks, expenses and uncertainties frequently encountered by companies in the biotechnology industry as discussed below. While the Company has been able to raise multiple rounds of financing, there can be no assurance that in the event the Company requires additional financing, such financing will be available on terms which are favorable or at all. Failure to raise sufficient capital when needed or generate sufficient cash flow from operations would impact the ability to pursue business strategies and could require the Company to delay, scale back or discontinue one or more product development programs, or other aspects of the Company's business objectives.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Such management estimates include, but are not limited to, those related to revenue recognition, marketable securities, manufacturing accruals, accrued research and development expenses, stock-based compensation, operating lease right-of-use (ROU) assets and liabilities, income tax uncertainties and the valuation of deferred tax assets. The Company bases its estimates on its historical experience and also on assumptions that it believes are reasonable; however, actual results could significantly differ from those estimates. The most significant estimates and assumptions that management considers in the preparation of our financial statements relate to revenue recognition, accrued research and development costs, and leases.
Segments	Segments The Company operates and manages its business as one reportable and operating segment, which is the business of developing engineered IgM antibodies for the treatment of cancer and autoimmune and inflammatory diseases. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating and evaluating financial performance. All long-lived assets are maintained in, and all losses are attributable to, the United States of America.
Concentration of Credit Risk and Other Risks and Uncertainties	Concentration of Credit Risk and Other Risks and Uncertainties Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company invests in money market funds, U.S. treasury securities, corporate bonds, commercial paper, and U.S. government agency securities. The Company maintains bank deposits in federally insured financial institutions and these deposits may exceed federally insured limits. The Company is exposed to credit risk in the event of a default by the financial institutions holding its cash, cash equivalents, and restricted cash, and bond issuers to the extent recorded on the balance sheets. The Company’s investment policy limits investments to high credit quality securities issued by the U.S. government and its agencies, highly rated banks, and corporate issuers, subject to certain concentration limits and restrictions on maturities. The Company has not experienced any material losses on its deposits of cash, cash equivalents, and marketable securities. The Company’s future results of operations involve a number of other risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the Company’s early stages of clinical drug development; uncertainties related to the use of engineered IgM antibodies, which is a novel and unproven therapeutic approach; the Company’s ability to advance product candidates into, and successfully complete, clinical trials on the timelines it projects; the Company’s ability to adequately demonstrate sufficient safety and efficacy of its product candidates; the Company’s ability to enroll patients in its ongoing and future clinical trials; the Company’s ability to successfully manufacture and supply its product candidates for clinical trials; the occurrence of any event or circumstance that could give rise to the termination of the Company’s collaborations with third parties; the Company’s ability to obtain additional capital to finance its operations; uncertainties related to the projections of the size of patient populations suffering from the diseases the Company is targeting; the Company’s ability to obtain, maintain, and protect its intellectual property rights; developments relating to the Company’s competitors and its industry, including competing product candidates and therapies; general economic and market conditions; and other risks and uncertainties, including those more fully described in the “Risk Factors” section of this Quarterly Report on Form 10-Q. The Company’s product candidates will require approvals from the U.S. Food and Drug Administration (FDA) and comparable foreign regulatory agencies prior to commercial sales in their respective jurisdictions. There can be no assurance that any product candidates will receive the necessary approvals. If the Company was denied approval, approval was delayed or the Company was unable to maintain approval for any product candidate, it could have a materially adverse impact on the Company.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash and cash equivalents. Cash equivalents consist primarily of amounts invested in money market funds, commercial paper, U.S. treasury securities, and U.S. government agency securities and are stated at fair value. Restricted cash consists of the remaining unused portion of a grant received from a non-profit organization which the Company will continue to utilize as it incurs expenses for services performed under the grant agreement.
Marketable Securities	Marketable Securities The Company’s marketable securities have been classified and accounted for as available-for-sale securities. Fixed income securities consist of U.S. treasury securities, U.S. government agency securities, corporate bonds, and commercial paper. The specific identification method is used to determine the cost basis of fixed income securities sold. These securities are recorded on the condensed consolidated balance sheets at fair value. Unrealized gains and losses on these securities are included as a separate component of accumulated other comprehensive loss. The cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in other income (expense). All available-for-sale securities are considered available to support current operations and are classified as current assets. The Company presents any credit losses identified as an allowance rather than as a reduction in the amortized cost of the available-for-sale securities. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value and recognized in other income (expense) in the condensed consolidated statements of operations. If neither criteria is met, the Company evaluates whether the decline in fair value is related to credit-related factors or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. Credit-related impairment losses, limited by the amount that the fair value is less than the amortized cost basis, are recorded through an allowance for credit losses in other income (expense). Any unrealized losses from declines in fair value below the amortized cost basis as a result of non-credit factors are recognized in accumulated other comprehensive income (loss), net of tax as a separate component of stockholders’ equity, along with unrealized gains. Realized gains and losses and declines in fair value, if any, on available-for-sale securities are included in other income (expense) in the condensed consolidated statements of operations. For purposes of identifying and measuring credit-related impairments, the Company’s policy is to exclude applicable accrued interest from both the fair value and amortized cost basis of the related security. The Company has elected to write-off uncollectible accrued interest receivable balances in a timely manner, which is defined by the Company as when interest due becomes 90 days delinquent. The accrued interest write-off will be recorded by reversing interest income. Accrued interest receivable is recorded to prepaid expenses and other current assets on the condensed consolidated balance sheets.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is determined using the straight-line method over the estimated useful lives of the respective assets, generally three to five years. Leasehold improvements are depreciated using the straight-line method over the shorter of the lease term or the estimated useful economic lives of the related assets. Assets are held in construction in progress until placed in service, upon which date, we begin to depreciate these assets. Upon retirement or sale of the assets, the cost and related accumulated depreciation and amortization are removed from the condensed consolidated balance sheets and the resulting gain or loss are recorded to the condensed consolidated statements of operations. Repairs and maintenance are charged to the condensed consolidated statements of operations as incurred.
Leases	Leases The Company determines if an arrangement is a lease at inception. In addition, the Company determines whether leases meet the classification criteria of a finance or operating lease at the lease commencement date considering: (1) whether the lease transfers ownership of the underlying asset to the lessee at the end of the lease term, (2) whether the lease grants the lessee an option to purchase the underlying asset that the lessee is reasonably certain to exercise, (3) whether the lease term is for a major part of the remaining economic life of the underlying asset, (4) whether the present value of the sum of the lease payments and residual value guaranteed by the lessee equals or exceeds substantially all of the fair value of the underlying asset, and (5) whether the underlying asset is of such a specialized nature that it is expected to have no alternative use to the lessor at the end of the lease term. As of June 30, 2024, the Company's lease population consisted of real estate leases and the Company did not have finance leases. Operating leases are included in operating lease ROU assets and lease liabilities in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. In determining the present value of lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date if the rate implicit in the lease is not readily determinable. The Company determines the incremental borrowing rate based on an analysis of corporate bond yields with a credit rating similar to the Company. The determination of the Company’s incremental borrowing rate requires management judgment including the development of a synthetic credit rating and cost of debt as the Company currently does not carry any debt. The Company believes that the estimates used in determining the incremental borrowing rate are reasonable based upon current facts and circumstances. Applying different judgments to the same facts and circumstances could result in the estimated amounts to vary. The operating lease ROU assets also include adjustments for prepayments and accrued lease payments and exclude lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options. Operating lease cost is recognized on a straight-line basis over the expected lease term. Variable lease costs represent payments that are dependent on usage, a rate or index. Variable lease cost primarily relates to common area maintenance charges. Lease agreements that include lease and non-lease components are accounted for as a single lease component. Lease agreements with a noncancelable term of less than 12 months are not recorded on the Company’s condensed consolidated balance sheets.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates the carrying amount of its long-lived assets, such as property and equipment, whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition are less than the carrying amount of the asset. There were no impairments of long-lived assets for the three and six months ended June 30, 2024 and 2023.
Fair Value Measurement	Fair Value Measurement The Company applies fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the condensed consolidated financial statements on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. 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, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows: Level 1—Observable inputs, such as quoted prices in active markets for identical assets or liabilities at the measurement date. Level 2—Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3—Unobservable inputs which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. Financial instruments classified within Level 2 of the fair value hierarchy are valued based on other observable inputs, including broker or dealer quotations or alternative pricing sources. When quoted prices in active markets for identical assets or liabilities are not available, the Company relies on non-binding quotes from its investment managers, which are based on proprietary valuation models of independent pricing services. These models generally use inputs such as observable market data, quoted market prices for similar instruments, or historical pricing trends of a security relative to its peers.
Revenue Recognition	Revenue Recognition For arrangements or transactions between participants determined to be within the scope of Accounting Standard Codification (ASC) Topic 606, “Revenue from Contracts with Customers” (Topic 606) the Company performs the following steps to determine the appropriate amount of revenue to be recognized as the Company fulfills its obligations: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company has entered into and may enter into additional collaboration agreements in the future under which it may obtain upfront payments, milestone payments, royalty payments, profit sharing, and other fees. Promises under these arrangements may include intellectual property licenses, research and development services, and the participation in joint committees. At contract inception, the Company assesses the goods or services promised and enforceable in a contract with a customer and identifies those distinct goods and services that represent a performance obligation. In assessing whether a promised good or service is distinct, and therefore a performance obligation, the Company considers factors such as the nature of the research, stage of development of the targets, manufacturing and commercialization capabilities of the customer and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, the Company combines that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct. Promised goods and services that are not material in the context of the contract are not considered performance obligations. Additional goods or services that are exercisable at a customer’s discretion, including substitution rights, are assessed to determine if they provide a material right to the customer and if so, they are considered performance obligations. The transaction price is the amount of consideration to which the Company expects to be entitled in exchange for transferring promised goods or services to a customer. The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Non-refundable upfront payments are considered fixed consideration and included in the transaction price. If an arrangement includes development, regulatory or commercial milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. The Company includes the amount of estimated variable consideration, including milestones, in the transaction price to the extent that it is probable that a significant reversal of cumulative revenue recognized will not occur. Milestone payments that are not within the Company’s control or the licensee’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. For arrangements with licenses of intellectual property that include sales-based royalties, including milestone payments based on the level of sales, and if the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. If it is determined that multiple performance obligations exist, the transaction price is allocated at the inception of the agreement to all identified performance obligations based on the relative standalone selling prices (SSP), unless the consideration is variable and meets the criteria to be allocated entirely to one or more, but not all, performance obligations in the contract. The relative SSP for each deliverable is estimated using objective evidence if it is available. If SSP is not directly observable the Company estimates the SSP at an amount that would result in the allocation of the transaction price in an amount that depicts the amount of consideration to which the entity expects to be entitled in exchange for transferring the promised goods or services to the customer, using methods such as the expected cost plus margin approach. Once the transaction price has been allocated to a performance obligation using the applicable methodology, it is not subject to reassessment for subsequent changes in standalone selling prices. Collaboration revenue is recognized when, or as, the Company satisfies a performance obligation. The Company recognizes revenue over time by measuring the progress toward complete satisfaction of the relevant performance obligation using an appropriate input method based on the nature of the good or service promised to the customer. After contract inception, the transaction price is reassessed at every period end and updated for changes such as resolution of uncertain events. Management may be required to exercise considerable judgment in estimating revenue to be recognized. Judgment is required in identifying performance obligations, estimating the transaction price, including variable consideration, estimating the standalone selling prices of identified performance obligations, and applying the input method for revenue recognition, including the estimated budgets for each performance obligation. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s condensed consolidated balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Amounts recognized as revenue prior to receipt are recorded as contract assets in the Company’s condensed consolidated balance sheets. If the Company expects to have an unconditional right to receive consideration in the next twelve months, this will be classified in current assets. A net contract asset or liability is presented for each contract with a customer. Contract modifications occur when the price and /or scope of an arrangement changes. If the modification consists of adding new distinct goods or services in exchange for consideration that reflects standalone selling prices of these goods and services, the modification is accounted for as a separate contract with the customer. Otherwise, if the remaining goods and services are distinct from those previously provided, the existing contract is considered terminated, and the remaining consideration is allocated to the remaining goods and services as if this was a newly signed contract. If the remaining goods and services are not distinct from those previously provided, the effects of the modification are accounted for in a manner similar to the effect of a change in the estimated measure of progress, with cumulative catch-up in revenue recorded at the time of the modification. If some of the remaining goods and services are distinct from those previously provided and others are not, the Company applies principles consistent with the objectives of the modification guidance to account for the effects of the modification.
Collaborative Arrangements	Collaborative Arrangements The Company analyzes its agreements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (Topic 808). These assessments are performed throughout the life of the arrangements based on changes in the responsibilities of all parties in the arrangement.
Research and Development Expenses	Research and Development Expenses The Company expenses research and development costs as they are incurred. Research and development expenses consist primarily of: (i) personnel-related expenses, including salaries, benefits and stock-based compensation expense, for personnel in the Company’s research and development functions; (ii) fees paid to third parties such as contractors, consultants and contract research organizations (CROs) for conducting clinical trials, and other costs related to clinical and preclinical testing; (iii) costs related to acquiring and manufacturing research and clinical trial materials, including under agreements with third parties such as contract manufacturing organizations (CMOs), and other vendors; (iv) costs related to the preparation of regulatory submissions; (v) expenses related to laboratory supplies and services; (vi) fees under license agreements where no alternative future use exists; and (vii) depreciation of equipment and facilities expenses.
Accrued Research and Development Expenses	Accrued Research and Development Expenses The Company records accruals for estimated costs of research, preclinical studies, clinical trials, and manufacturing, which are significant components of research and development expenses. A substantial portion of the Company’s ongoing research and development activities is conducted by third-party service providers, CROs and CMOs. The Company’s contracts with CROs generally include pass-through fees such as laboratory supplies and services, regulatory expenses, investigator fees, travel costs and other miscellaneous costs, including shipping and printing fees. The Company’s contracts with the CMOs generally include fees such as initiation fees, reservation fees, verification run costs, materials and reagents expenses, taxes, etc. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to the Company under such contracts. The Company accrues the costs incurred under agreements with these third parties based on estimates of actual work completed in accordance with the respective agreements. The Company determines the estimated costs through discussions with internal personnel and external service providers as to the progress, or stage of completion or actual timeline (start-date and end-date) of the services and the agreed-upon fees to be paid for such services. In the event the Company makes advance payments, the payments are recorded as a prepaid expense and recognized as the services are performed. As actual costs become known, the Company adjusts its accruals. Although the Company does not expect its estimates to be materially different from amounts actually incurred, such estimates for the status and timing of services performed relative to the actual status and timing of services performed may vary and could result in the Company reporting amounts that are too high or too low in any particular period. The Company’s accrual is dependent, in part, upon the receipt of timely and accurate reporting from CROs and other third-party vendors. Variations in the assumptions used to estimate accruals including, but not limited to, the number of patients enrolled, the rate of patient enrollment and the actual services performed, may vary from the Company’s estimates, resulting in adjustments to clinical trial expenses in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect its financial condition and results of operations. Through June 30, 2024, there have been no material differences from the Company’s estimated accrued research and development expenses to actual expenses.
Acquired In-Process Research and Development Expenses	Acquired In-Process Research and Development Expenses The Company has entered into agreements (see Note 5 – License Agreements) with third parties to acquire the rights to develop and potentially commercialize certain products. Such agreements generally require an initial payment by the Company when the contract is executed. The purchase of license rights for use in research and development activities, including product development, are expensed as incurred and are classified as research and development expense. Additionally, the Company may be obligated to make future royalty payments in the event the Company commercializes the technology and achieves a certain sales volume. In accordance with ASC Topic 730, Research and Development (Topic 730), expenditures for research and development, including upfront licensing fees and milestone payments associated with products not yet been approved by the FDA, are charged to research and development expense as incurred. Future contract milestone and/or royalty payments will be recognized as expense after the achievement of the milestone and the corresponding milestone payment is legally due.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for stock-based compensation by measuring and recognizing compensation expense for all share-based awards made to employees, non-employees and directors based on estimated grant-date fair values. The Company uses the straight-line method to allocate compensation cost to reporting periods over the requisite service period, which is generally the vesting period. The grant date fair value of restricted stock units is estimated based on the closing stock price of the Company’s common stock on the date of grant. The grant date fair value of stock options granted to employees and directors is estimated using the Black-Scholes option-pricing model. The Company accounts for forfeitures as they occur. The fair value of each purchase right under the employee stock purchase plan (ESPP) is estimated at the beginning of the offering period using the Black-Scholes option pricing model and recorded as expense over the service period using the straight-line method.
Income Taxes	Income Taxes The Company accounts for income taxes using the liability method, whereby deferred tax asset and liability account balances are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company provides a valuation allowance when it is more likely than not that some portion, or all of the Company’s deferred tax assets will not be realized. The Company accounts for income tax contingencies using a benefit recognition model. If it considers that a tax position is more likely than not to be sustained upon audit, based solely on the technical merits of the position, it recognizes the benefit. The Company measures the benefit by determining the amount that is greater than 50% likely of being realized upon settlement, presuming that the tax position is examined by the appropriate taxing authority that has full knowledge of all relevant information. The Company is subject to taxation in the United States federal jurisdiction, and various state jurisdictions. The net operating loss and research and development credit carryforwards that are available for utilization in future years may be subject to examination by federal and state tax authorities. The Company’s policy is to recognize interest expense and penalties related to income tax matters as a component of income tax expense. As of June 30, 2024, there were no significant accruals for interest related to unrecognized tax benefits or tax penalties.
Comprehensive Loss	Comprehensive Loss Comprehensive loss represents the net loss for the period and other comprehensive loss. Other comprehensive loss reflects certain gains and losses that are recorded as a component of stockholders’ equity and are not reflected in the condensed consolidated statements of operations. The Company’s other comprehensive loss consists of changes in unrealized gains and losses on available-for-sale securities.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock (including non-voting common stock and pre-funded warrants) outstanding during the period, without consideration for all other common stock equivalents. Shares of common stock into which the pre-funded warrants may be exercised are considered outstanding for the purposes of computing net loss per share because the shares may be issued for little or no consideration, are fully vested, and are exercisable after the original issuance date. Diluted net loss per share is the same as basic net loss per share, since the effects of potentially dilutive securities are antidilutive given the net loss for each period presented.
Recently Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In October 2023, the FASB issued Accounting Standards Update (ASU) 2023-06, Disclosure Improvements - Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative, which will impact various disclosure areas. The amendments in ASU 2023-06 will be effective on the date the related disclosures are removed from Regulation S-X or Regulation S-K by the SEC, and will no longer be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. The Company is currently evaluating the impacts of this standard on its related disclosures. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280), which improves reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023 and is applicable to public entities, including those that have a single reportable segment. Early adoption is permitted. The Company is currently evaluating the impacts of this standard on its condensed consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures, which amends the guidance in ASC 740, Income Taxes. The ASU is intended to improve the transparency of income tax disclosures by requiring (1) consistent categories and greater disaggregation of information in the rate reconciliation and (2) income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. The ASU's amendments are effective for public business entities for annual periods beginning after December 15, 2024. Entities are permitted to early adopt the standard for annual financial statements that have not yet been issued or made available for issuance. Adoption is permitted either prospectively or retrospectively. The Company will adopt this ASU on a prospective basis. The Company is currently evaluating the impact of this standard but does not expect any material impacts on its condensed consolidated financial statements and related disclosures.

Stock-Based Compensation - Summary of Company's stock awards granted (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Number of Shares, Granted	35,474	697,236	1,400,817	716,450
Weighted-Average Grant Date Fair Value	$ 8.53	$ 12.43	$ 9.89	$ 12.63
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Number of Shares, Granted	29,805	1,475,238	1,552,298	1,726,338
Weighted-Average Grant Date Fair Value	$ 7.44	$ 9.92	$ 7.82	$ 10.92

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Restructuring Charges - Summary of Charges Related to Restructuring Activities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Restructuring Cost and Reserve [Line Items]
Incentive and Stock-Based Compensation	$ 1.9

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities:
Net Income (Loss)	$ (97,718)	$ (123,732)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	4,452	3,837
Stock-based compensation expense	16,350	25,356
Purchase net discount on marketable securities	2,262	3,361
Net accretion of discounts on marketable securities	(4,106)	(4,799)
Non-cash lease expense	2,850	2,668
Other	(1)	0
Changes in assets and liabilities:
Prepaid expenses and other current assets	458	(3,657)
Other non-current assets	378	(116)
Accounts payable	1,846	1,000
Accrued liabilities	(3,561)	(5,805)
Lease liabilities, net	(1,250)	(1,245)
Deferred Revenue	(1,751)	(970)
Net cash used in operating activities	(79,791)	(104,102)
Cash flows from investing activities:
Purchase of property, plant and equipment	(3,698)	(7,850)
Purchases of marketable securities	(117,027)	(165,691)
Proceeds from maturities and sales of marketable securities	153,868	237,040
Proceeds from sales of property, plant and equipment	32	0
Net cash provided by investing activities	33,175	63,499
Cash flows from financing activities:
Proceeds from exercise of stock options	257	89
Proceeds from purchases under the employee stock purchase plan	582	991
Proceeds from issuance of common stock in public offering and private placement, net of offering costs	0	68,947
Payment of deferred offering costs	(71)	0
Payment of employee taxes and exercise costs for shares withheld	(1)	0
Net cash provided by financing activities	767	70,027
Net (decrease) increase in cash, cash equivalents, and restricted cash	(45,849)	29,424
Beginning of period	113,112	121,920
End of period	67,263	151,344
Cash and cash equivalents	66,974	150,702
Restricted cash	289	642
Cash, cash equivalents, and restricted cash	67,263	151,344
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets recognized in exchange for lease obligations	117	1,490
Unpaid amounts related to purchase of property, plant and equipment	973	2,334
Unpaid amounts related to offering costs for public offering and private placement	$ 0	$ 476

Fair Value Measurement - Additional Information (Details) $ in Millions	Jun. 30, 2024 USD ($) Instrument	Dec. 31, 2023 USD ($) Instrument
Fair Value Disclosures [Abstract]
Number of financial instruments classified as level 3	0	0
Number of debt securities held	55	35
Accrued interest receivable \| $	$ 0.9	$ 0.8

Subsequent Events

6 Months Ended

Jun. 30, 2024

Subsequent Events [Abstract]

Subsequent Events

Note 11. Subsequent Events

On July 19, 2024, the Company completed an exchange of stock options for new restricted stock units (RSUs). The Company offered eligible employees with outstanding option awards that had an exercise price equal to or greater than $17.70 per share and granted on or prior to March 1, 2023, the opportunity to exchange those options for a number of RSUs with an aggregate fair value for financial accounting purposes substantially similar to the aggregate fair value of the options surrendered, subject to a 2-for-1 exchange ratio floor. The RSUs vest 50% on either the 1-year anniversary or 18-months after the exchange date and then quarterly thereafter over a total vesting period of two to three years, depending on the vesting status of the exchanged options. The Company accepted for exchange eligible options to purchase a total of 1,583,305 shares of the Company's common stock, which were cancelled in exchange for RSUs representing 657,427 shares of the Company's common stock.

Stockholders' Equity - Schedule of Number of Common Stock Reserved for Future Issuance (Details) - shares	Jun. 30, 2024	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Stock options, issued and outstanding	7,525,626	6,766,340
Restricted stock units	1,707,599	658,792
Stock options and restricted stock units, future issuance	3,623,814	3,536,312
Employee stock purchase plan, available for future grants	1,821,195	1,376,988
Pre-funded warrants	1,334,332	1,334,332
Total	16,012,566	13,672,764

License Agreements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Jan. 31, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment based on achievement of specified development	$ 0.0		$ 0.0
Research And Development Expense
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License expenses recognized	0.0	$ 0.2	0.6	$ 0.5
License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment based on achievement of specified development	361.9		361.9
License Agreement \| Medivir AB
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional milestone payment					$ 1.5
Milestone payment based on achievement of specified development	$ 0.0		$ 0.0
Upfront payment					1.0
License Agreement \| Medivir AB \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment based on achievement of specified development					$ 348.5

Fair Value Measurement - Summary of Contractual Maturities of Investments (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Due in less than one year	$ 239,955	$ 312,554
Due in more than one year	12,117	19,311
Total	$ 252,072	$ 331,865

Restructuring Charges (Additional Information) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended	12 Months Ended
	Dec. 31, 2023	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2024	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
Workforce Reduced, Percent	22.00%
Restructuring Charges		$ 0		$ 200	$ 1,800
Severance and Related Compensation			$ 3,700
Incentive and Stock-Based Compensation			$ (1,900)