0000950170-23-021521 | 10-Q | XBRL Viewer

Fair Value Measurement - Summary of Investments Measured and Recognized at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 370,101	$ 420,550
Gross Unrealized Gains	56	15
Gross Unrealized Losses	(403)	(716)
Fair Value	369,754	419,849
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	44,535	26,718
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	44,535	26,718
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	14,931
Included within cash and cash equivalents, Gross Unrealized Gains	5
Included within cash and cash equivalents, Gross Unrealized Losses	0
Included within cash and cash equivalents, Fair Value	14,936
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	54,866	66,732
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	(8)	16
Included within cash and cash equivalents, Fair Value	54,858	66,716
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	22,185	20,477
Included within cash and cash equivalents, Gross Unrealized Gains	8	7
Included within cash and cash equivalents, Gross Unrealized Losses	0	0
Included within cash and cash equivalents, Fair Value	22,193	20,484
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	111,569	127,234
Included within cash and cash equivalents, Gross Unrealized Gains	39	6
Included within cash and cash equivalents, Gross Unrealized Losses	(179)	(318)
Included within cash and cash equivalents, Fair Value	111,429	126,922
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	27,613	12,531
Included within cash and cash equivalents, Gross Unrealized Gains	0	2
Included within cash and cash equivalents, Gross Unrealized Losses	(33)	(3)
Included within cash and cash equivalents, Fair Value	27,580	12,530
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	57,553	142,726
Included within cash and cash equivalents, Gross Unrealized Gains	0	0
Included within cash and cash equivalents, Gross Unrealized Losses	(62)	(195)
Included within cash and cash equivalents, Fair Value	57,491	142,531
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	36,849	24,132
Included within cash and cash equivalents, Gross Unrealized Gains	4	0
Included within cash and cash equivalents, Gross Unrealized Losses	(121)	(184)
Included within cash and cash equivalents, Fair Value	$ 36,732	$ 23,948

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net loss	$ (59,309)	$ (51,894)
Other comprehensive income (loss):
Unrealized (loss) gain on marketable securities	354	(127)
Comprehensive loss	$ (58,955)	$ (52,021)

- Definition

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

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+ Details

Net Loss Per Share Attributable to Common Stockholders - Summary of Potentially Dilutive Securities Not Included in the Diluted Per Share Calculations (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	6,381,152	6,270,227
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities not included in diluted per share calculations	5,972,087	5,538,692
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	58,251	16,138
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	350,814	715,397

Sanofi Agreement (Tables)

3 Months Ended

Mar. 31, 2023

Sanofi Agreement [Abstract]

Schedule of contract liabilities for the periods

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


Three Months Ended March 31, 2023	December 31, 2022		Additions		Deductions			March 31, 2023
Contract liabilities:
Deferred revenue	$	148,931	$	—	$	(522	)	$	148,409

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2023

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:


	March 31,		December 31,
	2023		2022
Stock options, issued and outstanding		5,972,087		5,802,317
Restricted stock units		350,814		401,180
Stock options and restricted stock units, future issuance		2,808,852		1,310,601
Employee stock purchase plan, available for future grants		1,539,855		1,109,032
Pre-funded warrants		1,334,332		1,334,332
Total		12,005,940		9,957,462

Fair Value Measurement - Summary of Contractual Maturities of Investments (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Due in less than one year	$ 363,404	$ 419,849
Due in more than one year	6,350	0
Total	$ 369,754	$ 419,849

Sanofi Agreement - Schedule of Contract liabilities for the periods (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Sanofi Agreement [Abstract]
Deferred revenue, beginning balance	$ 148,931
Additions	0
Deductions	(522)
Deferred revenue, ending balance	$ 148,409

Sanofi Agreement (Additional Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	May 31, 2022	Mar. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred Revenue	$ 148,409	$ 148,931
Upfront payment received	150,000
Contract Assets	0			$ 0
Contract Liabilities		$ 0
Sanofi Agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred Revenue	148,400
Deferred Revenue, Current	3,600
Revenues	500
Revenue Transaction Price	150,000
Upfront payment received			$ 150,000
Development and regulatory milestones exchange	$ 1,065,000
European Medicines Agency [Member] \| Sanofi Agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Profit sharing ratio description	50:50
Development and regulatory milestones exchange	$ 940,000

Organization - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2020
Subsidiary Sale Of Stock [Line Items]
Accumulated deficit	$ (634,135)	$ (574,826)
Cash, and investments	$ 373,400
Underwritten Public Offering \| Pre-funded Warrant
Subsidiary Sale Of Stock [Line Items]
Pre-funded warrant, exercise price			$ 0.01

Fair Value Measurement - Summary of Available-for-sale Securities Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	$ 196,354	$ 253,829
Less than 12 months, unrealized losses	(403)	(716)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	196,354	253,829
Total, unrealized losses	(403)	(716)
U.S. Treasury Securities
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	65,954	99,870
Less than 12 months, unrealized losses	(179)	(318)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	65,954	99,870
Total, unrealized losses	(179)	(318)
Corporate Bonds
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	27,580	2,848
Less than 12 months, unrealized losses	(33)	(3)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	27,580	2,848
Total, unrealized losses	(33)	(3)
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	75,935	127,163
Less than 12 months, unrealized losses	(70)	(211)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	75,935	127,163
Total, unrealized losses	(70)	(211)
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Less than 12 months, fair value	26,885	23,948
Less than 12 months, unrealized losses	(121)	(184)
Greater than 12 months, fair value	0	0
Greater than 12 months, unrealized losses	0	0
Total, fair value	26,885	23,948
Total, unrealized losses	$ (121)	$ (184)

Defined Contribution Plan (Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Retirement Benefits [Abstract]
Maximum Employee contribution	100.00%
Defined Contribution Plan, Cost	$ 0.5
Matching contributions by Employer		0.00%

Stockholders' Equity - Pre-Funded Warrants - Additional Information (Details)	Dec. 31, 2020 $ / shares shares
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
Underwritten Public Offering \| Pre-funded Warrant
Class of Warrant or Right [Line Items]
Warrants to purchase an additional shares of common stock \| shares	1,334,332
Pre-funded warrant, exercise price \| $ / shares	$ 0.01

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2023
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, autoimmune and inflammatory diseases, and infectious 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, 2022 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 months ended March 31, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023 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, 2022, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 30, 2023.
Liquidity	Liquidity The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $634.1 million as of March 31, 2023. As of March 31, 2023, the Company had cash, cash equivalents, and marketable securities of $373.4 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, 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, autoimmune and inflammatory diseases, and infectious 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 sheet 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 statement 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 statement 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 sheet.
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 balance sheet and the resulting gain or loss are recorded to the statements of operations. Repairs and maintenance are charged to the 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 March 31, 2023, 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 sheet. 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 sheet.
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 months ended March 31, 2023 and 2022.
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 balance sheet. 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 balance sheet. 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.
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 March 31, 2023, 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. Due to the Company’s net operating loss carryforwards, the Company's income tax returns remain subject to examination by federal and state tax authorities for all tax years. 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 March 31, 2023, 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.
Reclassification	Reclassification Certain reclassifications have been made to prior period amounts to conform to current period presentation. These reclassifications did not have an impact on the Company’s results of operations or financial position as of March 31, 2023 and December 31, 2022.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. The measurement of expected credit losses is based on historical experience, current conditions, and reasonable and supportable forecasts that affect collectability. This ASU also eliminates the concept of “other-than-temporary” impairment when evaluating available-for-sale debt securities and instead focuses on determining whether any impairment is a result of a credit loss or other factors. An entity will recognize an allowance for credit losses on available-for-sale debt securities rather than an other-than-temporary impairment that reduces the cost basis of the investment. The Company adopted ASU 2016-13 on January 1, 2023, using the modified retrospective approach, and no cumulative effect adjustment to accumulated deficit was needed as of the adoption date. Additionally, no prior period amounts were adjusted. The adoption of ASU 2016-13 did not have a material impact on the Company’s condensed consolidated financial statements and all current period amounts are reported under the Available-for-Sale Debt Securities Impairment Model (ASC 326-30).

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 140,164	$ 121,231
Restricted Cash	658	689
Marketable securities	233,232	305,931
Prepaid expenses and other current assets	10,702	10,570
Total current assets	384,756	438,421
Property, plant and equipment, net	36,731	33,484
Operating lease right-of-use assets	39,098	39,591
Other non-current assets	2,157	2,003
Total assets	462,742	513,499
Current liabilities:
Accounts payable	3,972	2,512
Accrued liabilities	29,637	33,621
Lease liabilities	6,426	5,816
Deferred revenue	3,597	2,736
Total current liabilities	43,632	44,685
Lease liabilities, non-current	34,868	35,356
Deferred revenue, non-current	144,812	146,195
Total liabilities	223,312	226,236
Commitments and contingencies (Note 5)
Stockholders' equity:
Preferred stock, $0.01 par value; 200,000,000 shares authorized as of March 31, 2023 and December 31, 2022; no shares issued and outstanding as of March 31, 2023 and December 31, 2022	0	0
Additional paid-in-capital	873,480	862,359
Accumulated other comprehensive loss	(347)	(701)
Accumulated deficit	(634,135)	(574,826)
Total stockholders’ equity	239,430	287,263
Total liabilities and stockholders’ equity	462,742	513,499
Common Stock Class Undefined
Stockholders' equity:
Common stock, value	295	294
Non-voting Common Stock
Stockholders' equity:
Common stock, value	$ 137	$ 137

Fair Value Measurement - Additional Information (Details) $ in Millions	Mar. 31, 2023 USD ($) Instrument	Dec. 31, 2022 USD ($) Instrument
Fair Value Disclosures [Abstract]
Number of financial instruments classified as level 3	0	0
Number of debt securities held	54	69
Accrued interest receivable \| $	$ 0.6	$ 0.5

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, 2021	$ 244,908	$ 261	$ 64	$ 598,373	$ 66	$ (353,724)
Balance, shares at Dec. 31, 2021		26,066,818	6,431,205
Exercise of stock options, net of shares withheld for taxes and exercise costs	133			133
Exercise of stock options, net of shares withheld for taxes and exercise costs, shares		23,432
Vesting of restricted stock, shares		1,713
Unrealized (loss) gain on marketable securities	(127)				(127)
Stock-based compensation expense	11,499			11,499
Net loss	(51,894)					(51,894)
Balance at Mar. 31, 2022	204,519	$ 261	$ 64	610,005	193	(405,618)
Balance, shares at Mar. 31, 2022		26,091,963	6,431,205
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, Shares		40,774
Exercise of stock options	75			75
Vest of restricted stock units		$ 1		1
Issuance of fully vested restricted stock units, shares		64,863
Unrealized (loss) gain on marketable securities	354				354
Stock-based compensation expense	11,047			11,047
Net 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

Fair Value Measurement

3 Months Ended

Mar. 31, 2023

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):


		March 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	44,535	$	—	$	—		$	44,535
U.S. treasury securities	Level 1		14,931		5		—			14,936
Commercial paper	Level 2		54,866		—		(8	)		54,858
U.S. government agency securities	Level 2		22,185		8		—			22,193
Marketable securities:
U.S. treasury securities	Level 1		111,569		39		(179	)		111,429
Corporate bonds	Level 2		27,613		—		(33	)		27,580
Commercial paper	Level 2		57,553		—		(62	)		57,491
U.S. government agency securities	Level 2		36,849		4		(121	)		36,732
Total		$	370,101	$	56	$	(403	)	$	369,754


		December 31, 2022
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	26,718	$	—	$	—		$	26,718
Commercial paper	Level 2		66,732		—		(16	)		66,716
U.S. government agency securities	Level 2		20,477		7		—			20,484
Marketable securities:
U.S. treasury securities	Level 1		127,234		6		(318	)		126,922
Corporate bonds	Level 2		12,531		2		(3	)		12,530
Commercial paper	Level 2		142,726		—		(195	)		142,531
U.S. government agency securities	Level 2		24,132		—		(184	)		23,948
Total		$	420,550	$	15	$	(716	)	$	419,849

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 months ended March 31, 2023 and 2022. As of March 31, 2023 and December 31, 2022, there were no financial instruments classified as Level 3.

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 March 31, 2023 and December 31, 2022, aggregated by major security type and length of time in a continuous unrealized loss position:


	March 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	$	65,954	$	(179	)	$	—	$	—	$	65,954	$	(179	)
Corporate bonds		27,580		(33	)		—		—		27,580		(33	)
Commercial paper		75,935		(70	)		—		—		75,935		(70	)
U.S. government agency securities		26,885		(121	)		—		—		26,885		(121	)
Total	$	196,354	$	(403	)	$	—	$	—	$	196,354	$	(403	)


	December 31, 2022
	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	$	99,870	$	(318	)	$	—	$	—	$	99,870	$	(318	)
Corporate bonds		2,848		(3	)		—		—		2,848		(3	)
Commercial paper		127,163		(211	)		—		—		127,163		(211	)
U.S. government agency securities		23,948		(184	)		—		—		23,948		(184	)
Total	$	253,829	$	(716	)	$	—	$	—	$	253,829	$	(716	)

As of March 31, 2023 and December 31, 2022, the Company held 54 and 69 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 they will be required to sell the securities before recovery of the unamortized cost basis. As of March 31, 2023 and December 31, 2022, an allowance for credit losses has not been recognized. Given our intent and ability to hold such securities until recovery, and the lack of significant change in credit risk of these investments, we do not consider these marketable securities impaired as of March 31, 2023 and December 31, 2022.

There were no realized gains or losses on marketable securities for the three months ended March 31, 2023 and 2022. Interest on marketable securities is included in interest income. As of March 31, 2023 and December 31, 2022, the Company had accrued interest receivable of $0.6 million and $0.5 million, respectively, which was included in prepaid expenses and other current assets on the condensed consolidated balance sheet.

The following table summarizes the contractual maturities of the Company’s cash equivalents and marketable securities as of March 31, 2023 and December 31, 2022 at estimated fair value (in thousands):


	March 31,		December 31,
	2023		2022
Due in less than one year	$	363,404	$	419,849
Due in more than one year		6,350		—
Total	$	369,754	$	419,849

- 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 + Details

Stock-Based Compensation - Additional Information (Details) - 2018 Plan - shares	3 Months Ended
	Mar. 31, 2023	Jan. 01, 2022	Jan. 01, 2021
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Increase in number of shares		1,299,920	1,723,292
Outstanding stock including non-voting common stock, percent	4.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	2,808,852
Maximum
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Increase in number of shares	8,768,800

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2023	May 04, 2023
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	Mar. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
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		29,508,089
Non-voting Common Stock
Document and Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		13,687,883

Defined Contribution Plan

3 Months Ended

Mar. 31, 2023

Retirement Benefits [Abstract]

Retirement Benefits [Text Block]

Note 9. Defined Contribution Plan

The Company sponsors a 401(k) retirement plan for its employees. This plan provides for tax-deferred salary deductions for all employees. Employee contributions are voluntary. Employees may contribute up to 100% of their annual compensation to this plan, as limited by an annual maximum amount as determined by the IRS. During the three months ended March 31, 2023, the Company provided $0.5 million in matching contributions to the 401(k) plan. There were no matching contributions in the three months March 31, 2022.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Income Taxes

3 Months Ended

Mar. 31, 2023

Income Tax Disclosure [Abstract]

Income Tax Disclosure [Text Block]

Note 10. Income Taxes

The Company’s income tax provision was $0.1 million for the three months ended March 31, 2023, representing an effective tax rate of (0.1)%. There was no tax provision for the three months ended March 31, 2022. The increase in the income tax provision for the three months ended March 31, 2023, as compared to the same period in 2022 was primarily due to recognizing deferred income in 2023 from the $150.0 million Sanofi upfront payment received in 2022 (See Note 7 – Sanofi Agreement).

The Company continuously evaluates the need for a valuation allowance based on all available evidence, both positive and negative. As of March 31, 2023, the Company continues to maintain a full valuation allowance on all of its deferred tax assets. The Company's effective tax rate for the three months ended March 31, 2023 differed from the federal statutory income tax rate primarily due to the full valuation allowance recorded on its net federal and state deferred tax assets and non-deductible stock-based compensation.

The Company files U.S. federal and state tax returns. The Company is not currently under any examinations in any jurisdictions where it files a tax return.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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+ Details

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
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	29,500,073	29,394,436
Common stock, shares outstanding	29,500,073	29,394,436
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	13,687,883	13,687,883
Common stock, shares outstanding	13,687,883	13,687,883

License Agreements

3 Months Ended

Mar. 31, 2023

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 months ended March 31, 2023 and 2022, the Company recorded $0.3 million and $0.1 million, respectively, as research and development expense in our condensed consolidated statements of operations related to license agreements.

As of March 31, 2023, 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 $357.9 million plus royalties on net sales that range from single digits to mid-teens.

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 IGM-8444 in combination with birinapant. Under the terms of the agreement, should birinapant be successfully developed and approved, the Company is 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.

Stock-Based Compensation

3 Months Ended

Mar. 31, 2023

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, 2023 and 2022, an additional 1,723,292 and 1,299,920 shares, respectively, became available for issuance under the 2018 Plan. As of March 31, 2023, the 2018 Plan had 2,808,852 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 statements of operations as follows (in thousands):


	Three Months Ended
	March 31,
	2023		2022
Research and development	$	6,439	$	6,607
General and administrative		4,608		4,892
Total stock-based compensation expense	$	11,047	$	11,499

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


	For the Three Months Ended March 31,
	2023				2022
	Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value
Stock options		251,100	$	16.84		1,859,642	$	12.85
Restricted stock units		19,214	$	20.06		374,755	$	16.06

Stockholders' Equity - Schedule of Number of Common Stock Reserved for Future Issuance (Details) - shares	Mar. 31, 2023	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Stock options, issued and outstanding	5,972,087	5,802,317
Restricted stock units	350,814	401,180
Stock options and restricted stock units, future issuance	2,808,852	1,310,601
Employee stock purchase plan, available for future grants	1,539,855	1,109,032
Pre-funded warrants	1,334,332	1,334,332
Total	12,005,940	9,957,462

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (59,309)	$ (51,894)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,664	1,224
Stock-based compensation expense	11,047	11,499
Purchase of net discount (premium) on marketable securities	1,705	(20)
Net (accretion of discount) amortization of premiums on marketable securities	(2,487)	165
Non-cash lease expense	1,323	1,001
Changes in assets and liabilities:
Prepaid expenses and other current assets	(58)	933
Other non-current assets	(154)	29
Accounts payable	1,604	(1,244)
Accrued liabilities	(5,102)	362
Lease liabilities, net	(708)	(944)
Deferred Revenue	(522)	0
Net cash used in operating activities	(50,997)	(38,889)
Cash flows from investing activities:
Purchase of property, plant and equipment	(3,937)	(2,977)
Purchases of marketable securities	(89,274)	(40,126)
Proceeds from maturities of marketable securities	163,035	24,000
Net cash provided by (used in) investing activities	69,824	(19,103)
Cash flows from financing activities:
Proceeds from exercise of stock options	75	133
Payment of deferred offering costs	0	(61)
Net cash provided by financing activities	75	72
Net increase (decrease) in cash, cash equivalents, and restricted cash	18,902	(57,920)
Beginning of period	121,920	134,035
End of period	140,822	76,115
Cash and cash equivalents	140,164	75,417
Restricted cash	658	698
Cash, cash equivalents, and restricted cash	140,822	76,115
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets recognized in exchange for lease obligations	830	2,093
Unpaid amounts related to purchase of property, plant and equipment	2,439	231
Unpaid amounts related to offering costs for public offering	$ 0	$ 460

Stock-Based Compensation - Summary of Company's stock awards granted (Details) - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Number of Shares, Granted	19,214	374,755
Weighted-Average Grant Date Fair Value	$ 20.06	$ 16.06
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award Line Items
Number of Shares, Granted	251,100	1,859,642
Weighted-Average Grant Date Fair Value	$ 16.84	$ 12.85

Stockholders' Equity

3 Months Ended

Mar. 31, 2023

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Note 6. Stockholders' Equity

Common Stock and Non-Voting Common Stock

As of March 31, 2023 and December 31, 2022, 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 March 31, 2023 and December 31, 2022, no dividends have been declared.

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


	March 31,		December 31,
	2023		2022
Stock options, issued and outstanding		5,972,087		5,802,317
Restricted stock units		350,814		401,180
Stock options and restricted stock units, future issuance		2,808,852		1,310,601
Employee stock purchase plan, available for future grants		1,539,855		1,109,032
Pre-funded warrants		1,334,332		1,334,332
Total		12,005,940		9,957,462

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 March 31, 2023, 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 11 – Net Loss Per Share Attributable to Common Stockholders).

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI https://asc.fasb.org/topic&trid=2208762

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (h)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
-Paragraph 14
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-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
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-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

+ Details

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) Segment	Mar. 31, 2022 USD ($)
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
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
Maximum
Summary of Significant Accounting Policies [Line Items]
Property and equipment estimated useful life	5 years

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - 2010 Plan, 2018 Plan and ESPP - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	$ 11,047	$ 11,499
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	6,439	6,607
General And Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs Line Items
Total stock-based compensation expense	$ 4,608	$ 4,892

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Collaboration revenue	$ 522	$ 0
Operating expenses:
Research and development	50,894	38,875
General and administrative	13,002	13,081
Total operating expenses	63,896	51,956
Loss from operations	(63,374)	(51,956)
Other income (expense)
Interest income	4,172	54
Other income (expense)	(20)	8
Total other income (expense)	4,152	62
Loss before income tax expense	(59,222)	(51,894)
Income tax expense	(87)	0
Net loss	$ (59,309)	$ (51,894)
Net loss per share, basic	$ (1.33)	$ (1.53)
Net loss per share, diluted	$ (1.33)	$ (1.53)
Weighted-average common shares outstanding, basic	44,466,764	33,838,895
Weighted-average common shares outstanding, diluted	44,466,764	33,838,895

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

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


	Three Months Ended
	March 31,
	2023		2022
Research and development	$	6,439	$	6,607
General and administrative		4,608		4,892
Total stock-based compensation expense	$	11,047	$	11,499

Summary of Company's stock awards granted

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


	For the Three Months Ended March 31,
	2023				2022
	Grants		Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value
Stock options		251,100	$	16.84		1,859,642	$	12.85
Restricted stock units		19,214	$	20.06		374,755	$	16.06

Accrued Liabilities

3 Months Ended

Mar. 31, 2023

Balance Sheet Related Disclosures [Abstract]

Accrued Liabilities

Note 4. Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	March 31,		December 31,
	2023		2022
Accrued research and development materials and services	$	19,144	$	20,747
Accrued professional services		2,728		1,759
Accrued compensation		7,402		10,920
Other		363		195
Total accrued liabilities	$	29,637	$	33,621

Fair Value Measurement (Tables)

3 Months Ended

Mar. 31, 2023

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):


		March 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	44,535	$	—	$	—		$	44,535
U.S. treasury securities	Level 1		14,931		5		—			14,936
Commercial paper	Level 2		54,866		—		(8	)		54,858
U.S. government agency securities	Level 2		22,185		8		—			22,193
Marketable securities:
U.S. treasury securities	Level 1		111,569		39		(179	)		111,429
Corporate bonds	Level 2		27,613		—		(33	)		27,580
Commercial paper	Level 2		57,553		—		(62	)		57,491
U.S. government agency securities	Level 2		36,849		4		(121	)		36,732
Total		$	370,101	$	56	$	(403	)	$	369,754


		December 31, 2022
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	Level 1	$	26,718	$	—	$	—		$	26,718
Commercial paper	Level 2		66,732		—		(16	)		66,716
U.S. government agency securities	Level 2		20,477		7		—			20,484
Marketable securities:
U.S. treasury securities	Level 1		127,234		6		(318	)		126,922
Corporate bonds	Level 2		12,531		2		(3	)		12,530
Commercial paper	Level 2		142,726		—		(195	)		142,531
U.S. government agency securities	Level 2		24,132		—		(184	)		23,948
Total		$	420,550	$	15	$	(716	)	$	419,849

Schedule of Unrealized Loss on Marketable Securities


	March 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	$	65,954	$	(179	)	$	—	$	—	$	65,954	$	(179	)
Corporate bonds		27,580		(33	)		—		—		27,580		(33	)
Commercial paper		75,935		(70	)		—		—		75,935		(70	)
U.S. government agency securities		26,885		(121	)		—		—		26,885		(121	)
Total	$	196,354	$	(403	)	$	—	$	—	$	196,354	$	(403	)


	December 31, 2022
	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	$	99,870	$	(318	)	$	—	$	—	$	99,870	$	(318	)
Corporate bonds		2,848		(3	)		—		—		2,848		(3	)
Commercial paper		127,163		(211	)		—		—		127,163		(211	)
U.S. government agency securities		23,948		(184	)		—		—		23,948		(184	)
Total	$	253,829	$	(716	)	$	—	$	—	$	253,829	$	(716	)

Summary of Contractual Maturities of Marketable Securities


	March 31,		December 31,
	2023		2022
Due in less than one year	$	363,404	$	419,849
Due in more than one year		6,350		—
Total	$	369,754	$	419,849

Sanofi Agreement

3 Months Ended

Mar. 31, 2023

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 upon satisfaction of the closing conditions. Under the terms of the Sanofi Agreement, the Company will generate, develop, manufacture and commercialize IgM antibodies directed to six primary targets, three of which are intended as oncology targets and three of which are intended as immunology targets.

For each oncology target collaboration program, the Company will lead research and development activities, and assume related costs, through receipt of the first marketing approval for a licensed product directed to that oncology target by the Food and Drug Administration (FDA) or European Medicines Agency (EMA) in exchange for up to $940 million in development and regulatory milestones per oncology target. After receipt of the first marketing approval for a licensed product directed to an oncology target, Sanofi will lead all subsequent development and commercialization activities for that oncology target. For each licensed product directed to an oncology target, the companies will share profits 50:50 in certain major markets, subject to certain exceptions, and the Company will be eligible to receive tiered low double-digit to mid-teen royalties on net sales of licensed products in the rest of world, subject to certain reductions and offsets. However, the Company has the right to opt-out of any future research and development responsibilities for each oncology target collaboration program at any time after completion of a Phase 1 clinical trial for an oncology target collaboration program. As a result of exercising this opt-out right, the Company would no longer share profits 50:50 but would instead be eligible for certain sales milestones and tiered royalties on net sales.

For each immunology target collaboration program, the Company will 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.

After considering the level of involvement and participation in the joint activities and the related exposure to the risks and rewards of the collaboration, the Company determined that at inception, the Sanofi Agreement does not fall within the collaborative arrangement guidance in Topic 808, and that Sanofi is a customer of the Company for all initial promised goods and services and therefore the agreement is directly within the scope of Topic 606.

The Company identified promised goods and services in the Sanofi Agreement related to the grant of intellectual property license, 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 are 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, which consist of the granting of intellectual property licenses and the performance of specified research, development and other various activities, 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 are 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 are six performance obligations in the Sanofi Agreement, one for each target, that are 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 evaluated 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 March 31, 2023, 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.

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 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.

For the three months ended March 31, 2023, the Company recognized collaboration revenue from a customer related to the Sanofi Agreement of $0.5 million. As of March 31, 2023, $148.4 million was recorded as deferred revenue, of which $3.6 million was current, on the condensed consolidated balance sheet related to the Sanofi Agreement. 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 derecognized 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 table presents changes in the Company’s customer contract liabilities for the periods presented (in thousands):


Three Months Ended March 31, 2023	December 31, 2022		Additions		Deductions			March 31, 2023
Contract liabilities:
Deferred revenue	$	148,931	$	—	$	(522	)	$	148,409

The Company had no customer contract liabilities during the three months ended March 31, 2022 and no customer contract assets during the three months ended March 31, 2023 and 2022.

License Agreements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Jan. 31, 2021
Research And Development Expense
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License expenses recognized	$ 0.3	$ 0.1
License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment based on achievement of specified development	$ 357.9
License Agreement \| Medivir AB
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional milestone payment			$ 1.5
Upfront payment			$ 1.0

Organization	3 Months Ended
Organization	Mar. 31, 2023
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, autoimmune and inflammatory diseases, and infectious 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, 2022 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 months ended March 31, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023 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, 2022, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 30, 2023. Liquidity The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $634.1 million as of March 31, 2023. As of March 31, 2023, the Company had cash, cash equivalents, and marketable securities of $373.4 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, 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 - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Accrued research and development materials and services	$ 19,144	$ 20,747
Accrued professional services	2,728	1,759
Accrued compensation	7,402	10,920
Other	363	195
Total accrued liabilities	$ 29,637	$ 33,621

Accrued Liabilities (Tables)

3 Months Ended

Mar. 31, 2023

Balance Sheet Related Disclosures [Abstract]

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	March 31,		December 31,
	2023		2022
Accrued research and development materials and services	$	19,144	$	20,747
Accrued professional services		2,728		1,759
Accrued compensation		7,402		10,920
Other		363		195
Total accrued liabilities	$	29,637	$	33,621

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2023
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, autoimmune and inflammatory diseases, and infectious 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 sheet 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 statement 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 statement 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 sheet. 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 balance sheet and the resulting gain or loss are recorded to the statements of operations. Repairs and maintenance are charged to the 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 March 31, 2023, 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 sheet. 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 sheet. 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 months ended March 31, 2023 and 2022. 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 balance sheet. 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 balance sheet. 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. 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 March 31, 2023, 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. Due to the Company’s net operating loss carryforwards, the Company's income tax returns remain subject to examination by federal and state tax authorities for all tax years. 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 March 31, 2023, 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. Reclassification Certain reclassifications have been made to prior period amounts to conform to current period presentation. These reclassifications did not have an impact on the Company’s results of operations or financial position as of March 31, 2023 and December 31, 2022. Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. The measurement of expected credit losses is based on historical experience, current conditions, and reasonable and supportable forecasts that affect collectability. This ASU also eliminates the concept of “other-than-temporary” impairment when evaluating available-for-sale debt securities and instead focuses on determining whether any impairment is a result of a credit loss or other factors. An entity will recognize an allowance for credit losses on available-for-sale debt securities rather than an other-than-temporary impairment that reduces the cost basis of the investment. The Company adopted ASU 2016-13 on January 1, 2023, using the modified retrospective approach, and no cumulative effect adjustment to accumulated deficit was needed as of the adoption date. Additionally, no prior period amounts were adjusted. The adoption of ASU 2016-13 did not have a material impact on the Company’s condensed consolidated financial statements and all current period amounts are reported under the Available-for-Sale Debt Securities Impairment Model (ASC 326-30).

Net Loss Per Share Attributable to Common Stockholders

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share Attributable to Common Stockholders

Note 11. 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:


	March 31,
	2023		2022
Stock options		5,972,087		5,538,692
Estimated shares issuable under the employee stock purchase plan		58,251		16,138
Unvested restricted stock units		350,814		715,397
Total		6,381,152		6,270,227

Stockholders' Equity - Additional Information (Details)	3 Months Ended	12 Months Ended
Stockholders' Equity - Additional Information (Details)	Mar. 31, 2023 USD ($) Vote $ / shares shares	Dec. 31, 2022 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

Net Loss Per Share Attributable to Common Stockholders (Tables)

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

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:


	March 31,
	2023		2022
Stock options		5,972,087		5,538,692
Estimated shares issuable under the employee stock purchase plan		58,251		16,138
Unvested restricted stock units		350,814		715,397
Total		6,381,152		6,270,227

Income Taxes (Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Tax Provision	$ 0.1	$ 0.0
Upfront payment received	$ 150.0
Effective tax rate	0.10%