0001439222-24-000035 | 10-K | XBRL Viewer | Agios Pharmaceuticals INC

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Net Income (Loss) per Share (Details) - shares	12 Months Ended
Net Income (Loss) per Share (Details) - shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	6,804,118	6,932,511	5,841,614
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	5,263,681	5,772,564	4,798,826
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	1,346,701	1,117,921	1,002,924
Performance-based stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	145,023	0	0
Employee Stock Purchase Plan shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	48,713	42,026	39,864

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Principles of consolidation

The consolidated financial statements include our accounts and the accounts of our wholly owned subsidiaries, Agios Securities Corporation, Agios International Sarl (GmbH), Agios Germany GmbH, Agios Netherlands B.V., Agios Italy S.R.L., Agios France SARL, and Agios Limited. All intercompany transactions have been eliminated in consolidation. The consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles, or U.S. GAAP.

Use of estimates

The preparation of our consolidated financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenues and expenses and related disclosure of contingent assets and liabilities. On an ongoing basis we evaluate our estimates, judgments and methodologies. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenues and expenses. The full extent to

which the recent COVID-19 pandemic, or other pandemics or public health emergencies, may in the future directly or indirectly impact our business, results of operations and financial condition, including expenses, reserves and allowances, clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain.

Cash and cash equivalents

We consider highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Cash equivalents are stated at fair value.

Accounts receivable, net

Our trade accounts receivable arise from product sales and represent amounts due from specialty distributors and specialty pharmacy providers in the U.S. We monitor the financial performance and creditworthiness of our customers so that we can properly assess and respond to changes in their credit profile. We reserve against these receivables for estimated losses that may arise from a customer’s inability to pay. Amounts determined to be uncollectible are charged or written-off against the reserve.

Inventory

Inventory is stated at the lower of cost or estimated net realizable value on a first-in, first-out basis. Prior to the regulatory approval of our product candidates, we incur expenses for the manufacture of drug product that could potentially be available to support the commercial launch of those products. Until the date at which regulatory approval has been received or is otherwise considered probable, we record all such costs as research and development expenses. Upon approval of our wholly owned product, PYRUKYND®, by the FDA on February 17, 2022 for the treatment of hemolytic anemia in adults with PK deficiency in the United States, we began to capitalize inventories of PYRUKYND®.

Revenue recognition

Under Accounting Standards Codification 606, Revenue from Contracts with Customers, or ASC 606, revenue is recognized when the customer obtains control of promised goods or services, in an amount that reflects the consideration that we expect to receive in exchange for those goods or services. To determine revenue recognition for arrangements that have been determined to be within the scope of ASC 606, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer.

This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments.

Once the contract is determined to be within the scope of ASC 606, we assess the goods or services promised within each contract and determine those that are performance obligations, and assess whether each promised good or service is distinct. We will then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

Product Revenue

We generate product revenue from sales of PYRUKYND® to a limited number of specialty distributors and specialty pharmacy providers, or collectively, the Customers. These Customers subsequently resell PYRUKYND® to pharmacies or dispense PYRUKYND® directly to patients. In addition to distribution agreements with Customers, we enter into arrangements with healthcare providers and payors that provide for government-mandated and/or privately-negotiated rebates, chargebacks and discounts with respect to the purchase of PYRUKYND®.

The performance obligation related to the sale of PYRUKYND® is satisfied and revenue is recognized when the Customer obtains control of the product, which occurs at a point in time, typically upon delivery to the Customer.

Revenues from product sales are recorded at the net sales price, or transaction price, which includes estimates of variable consideration for which reserves are established and result from contractual adjustments, government rebates, returns and other allowances that are offered within the contracts with our Customers, healthcare providers, payors and other indirect customers relating to the sale of our products.

Contractual Adjustments. We generally provide Customers with discounts, including prompt pay discounts, and allowances that are explicitly stated in the contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, we receive sales order management, data and distribution services from certain Customers.

Chargebacks and discounts represent the estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at prices lower than the list prices charged to Customers who directly purchase the product from us. Customers charge us for the difference between what they pay for the product and the ultimate selling price to the qualified healthcare providers. These reserves are estimated using the expected value method, based upon a range of possible outcomes that are probability-weighted for the estimated channel mix and are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue.

Government Rebates. Government rebates include Medicare, TriCare, and Medicaid rebates, which we estimate using the expected value method, based upon a range of possible outcomes that are probability-weighted for the estimated payor mix. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue. For Medicare, we also estimate the number of patients in the prescription drug coverage gap for whom we will owe an additional liability under the Medicare Part D program.

Returns. We estimate the amount of product sales that may be returned by Customers and record this estimate as a reduction of revenue in the period the related product revenue is recognized. We currently estimate product return liabilities using the expected value method, based on available industry data, including our visibility into the inventory remaining in the distribution channel.

Cost of sales

Cost of sales consists primarily of manufacturing costs for sales of PYRUKYND®. Based on our policy to expense costs associated with the manufacturing of our products prior to regulatory approval, certain of the manufacturing costs associated with product shipments of PYRUKYND® recorded during the twelve months ended December 31, 2023 and 2022 were expensed prior to February 17, 2022 and, therefore, are not included in costs of sales during the twelve months ended December 31, 2023 and 2022.

Marketable securities

Marketable securities at December 31, 2023 and 2022 consisted of investments in U.S. Treasuries, government securities and corporate debt securities. We determine the appropriate classification of the securities at the time they are acquired and evaluate the appropriateness of such classifications at each balance sheet date. We classify our marketable securities as available-for-sale pursuant to ASC 320, Investments – Debt and Equity Securities. Marketable securities are recorded at fair value. Unrealized gains and losses are included as a component of accumulated other comprehensive (loss) income in the consolidated balance sheets and statements of stockholders’ equity and a component of total comprehensive (loss) income in the consolidated statements of comprehensive (loss) income, until realized. Realized gains and losses are included in investment income on a specific-identification basis.

At December 31, 2023 and 2022, we held both current and non-current investments. Investments classified as current are those that: (i) have a maturity of less than one year, or (ii) have a maturity of one to two years but we intend to liquidate within the next twelve months. Investments classified as non-current are those that: (i) have a maturity of one to two years, and (ii) we do not intend to liquidate within the next one year, although these funds are available for use and therefore classified as available-for-sale.

We review marketable securities for impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable. Unrealized losses are evaluated for impairment under ASC 326, Financial Instruments - Credit Losses, to determine if the impairment is credit-related or noncredit-related. Credit-related impairment is recognized as an allowance on the balance sheet with a corresponding adjustment to earnings, and noncredit-related impairment is recognized in other comprehensive (loss) income, net of taxes. Evidence considered in this assessment includes reasons for the impairment, compliance with our investment policy, the severity of the impairment, collectability of the security, and any adverse conditions specifically related to the security, an industry, or geographic area.

Fair value measurements

We record cash equivalents and marketable securities at fair value. ASC 820, Fair Value Measurements and Disclosures, establishes a fair value hierarchy for those instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and our own assumptions (unobservable inputs). The hierarchy consists of three levels:

Level 1 – Unadjusted quoted prices in active markets for identical assets or liabilities.

Level 2 – Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability.

Level 3 – Unobservable inputs that reflect our own assumptions about the assumptions market participants would use in pricing the asset or liability in which there is little, if any, market activity for the asset or liability at the measurement date.

Our financial assets, which include cash equivalents and marketable securities, have been initially valued at the transaction price, and subsequently revalued at the end of each reporting period, utilizing third-party pricing services or other observable market data. The pricing services utilize industry standard valuation models, including both income and market based approaches, and observable market inputs to determine value. After completing our validation procedures, we did not adjust or override any fair value measurements provided by the pricing services as of December 31, 2023 or 2022. Fair value information for these assets, including their classification in the fair value hierarchy is included in Note 3 , Fair Value Measurements.

There have been no changes to the valuation methods during the years ended December 31, 2023 and 2022. We evaluate transfers between levels at the end of each reporting period.

The carrying amounts of other receivables, prepaid expenses and other current assets, accounts payable, and accrued expenses approximate their fair values due to their short-term maturities.

Concentrations of credit risk

Financial instruments which potentially subject us to credit risk consist primarily of cash, cash equivalents, and marketable securities. We hold these investments in highly rated financial institutions, and, by policy, limit the amounts of credit exposure to any one financial institution. These amounts at times may exceed federally insured limits. We have not experienced any credit losses in such accounts and do not believe we are exposed to any significant credit risk on these funds. We have no off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts, or other hedging arrangements.

Property and equipment

Property and equipment consist of laboratory equipment, computer equipment and software, leasehold improvements, furniture and fixtures, and office equipment. Costs of major additions and betterment are capitalized; maintenance and repairs, which do not improve or extend the life of the respective assets, are charged to expense as incurred. Upon retirement or sale, the cost of the disposed asset and the related accumulated depreciation are removed from the accounts and the resulting gain or loss is recognized.

Property and equipment is stated at cost, and depreciated using the straight-line method over the estimated useful lives of the respective assets:


						Years
Laboratory equipment						5
Computer equipment and software						3
Furniture and fixtures						5
Office equipment						5

Leasehold improvements are amortized over the lesser of the remaining lease term or the estimated useful life of the improvement.

Impairment of long-lived assets

We periodically evaluate our long-lived assets for potential impairment in accordance with ASC 360, Property, Plant and Equipment. Potential impairment is assessed when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recovered. Recoverability of these assets is assessed based on the undiscounted expected future cash flows from the assets, considering a number of factors, including past operating results, budgets and economic projections, market trends and product development cycles. If impairments are identified, assets are written down to their estimated fair value. We did not recognize any impairment charges through December 31, 2023.

Leases

We determine if an arrangement is a lease at inception. An arrangement is determined to contain a lease if the contract conveys the right to control the use of an identified property or equipment for a period of time in exchange for consideration. If we can benefit from the various underlying assets of a lease on their own or together with other resources that are readily available, or if the various underlying assets are neither highly dependent on nor highly interrelated with other underlying assets in the

arrangement, they are considered to be a separate lease component. In the event multiple underlying assets are identified, the lease consideration is allocated to the various components based on each of the component’s relative fair value.

Operating lease assets represent our right to use an underlying asset for the lease term and operating lease liabilities represent our obligation to make lease payments arising from the leasing arrangement. Operating lease assets and operating lease liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As most of our leases do not provide an implicit rate, in determining the operating lease liabilities we use an estimate of our incremental borrowing rate. The incremental borrowing rate is determined using two alternative credit scoring models to estimate our credit rating, adjusted for collateralization. The calculation of the operating lease assets includes any lease payments made and excludes any lease incentives. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option.

For operating leases, we record operating lease assets and lease liabilities in our consolidated balance sheets. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Short-term leases, or leases that have a lease term of 12 months or less at commencement date, are excluded from this treatment and are recognized on a straight-line basis over the term of the lease.

We have not entered into any material short-term leases or financing leases as of December 31, 2023.

Research and development costs

Research and development costs, including those accrued as of each balance sheet date, are expensed as incurred. These costs include salaries and personnel-related costs, consulting fees, fees paid for contract research services, fees paid to contract research organizations, or CROs, and other third parties in connection with clinical trials and preclinical development activities, fees paid to investigative sites in connection with clinical studies, the costs associated with the product manufacturing, development, and distribution of clinical supplies, the costs of laboratory equipment and facilities, and other external costs.

Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are deferred and capitalized. Additionally, there may be instances in which payments made to our vendors will exceed the level of services provided, and result in a prepayment of the research and development expense. The capitalized amounts are expensed as the related goods are delivered or the services are performed. We estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid accordingly.

Stock-based compensation

We account for stock-based compensation awards in accordance with ASC 718, Compensation –Stock Compensation, or ASC 718. For stock-based awards granted to employees, non-employees and members of the board of directors for their services and for participation in our employee stock purchase plan, we estimate the grant date fair value of each option award using the Black-Scholes option-pricing model. The use of the Black-Scholes option-pricing model requires us to make assumptions with respect to the expected term of the option, the expected volatility of the common stock consistent with the expected life of the option, risk-free interest rates and expected dividend yields of the common stock. For awards subject to service-based vesting conditions, we recognize stock-based compensation expense equal to the grant date fair value of stock options on a straight-line basis over the requisite service period. For awards subject to performance-based vesting conditions, we recognize stock-based compensation expense if the performance condition is considered probable of achievement using management’s best estimates.

Income taxes

Income taxes are recorded in accordance with ASC 740, Accounting for Income Taxes, or ASC 740, which provides for deferred taxes using an asset and liability approach. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in our financial statements or tax returns. We determine our deferred tax assets and liabilities based on differences between the financial reporting and tax bases of assets and liabilities, which are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Valuation allowances are provided, if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.

We also account for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, we recognize the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances.

Comprehensive (loss) income

Comprehensive (loss) income is defined as the change in equity of a business enterprise during a period from transactions, and other events and circumstances, and currently consists of net loss and unrealized gains and losses on available-for-sale securities. Accumulated other comprehensive (loss) income consists entirely of unrealized gains and losses from available-for-sale securities as of December 31, 2023 and 2022.

Net (loss) income per share

Basic net (loss) income per share is calculated by dividing net (loss) income by the weighted-average shares outstanding during the period, without consideration for common stock equivalents. Diluted net (loss) income per share is calculated by adjusting weighted-average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the dilutive net (loss) income per share calculation, stock options, restricted stock units, or RSUs, performance-based stock units, or PSUs, and market-based stock units, or MSUs, for which the performance and market vesting conditions, respectively, have been deemed probable, and employee stock purchase plan shares are considered to be common stock equivalents but are excluded from the calculation of diluted net (loss) income per share as their effect would be anti-dilutive.

We utilize the control number concept in the computation of diluted earnings per share to determine whether potential common stock equivalents are dilutive. The control number used is loss from continuing operations. The control number concept requires that the same number of potentially dilutive securities applied in computing diluted earnings per share from continuing operations be applied to all other categories of income or loss, regardless of their anti-dilutive effect on such categories. Since we had a net loss from continuing operations for all periods presented, no dilutive effect has been recognized in the calculation of income (loss) from discontinued operations per share or net (loss) income per share.

Segment and geographic information

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker or decision-making group in making decisions on how to allocate resources and assess performance. Our chief operating decision maker is the chief executive officer. Our chief operating decision maker and we view our operations and manage our business as one operating segment.

Discontinued operations

We accounted for the sale of our oncology business in the first quarter of 2021 in accordance with ASC 205, Discontinued Operations and Accounting Standards Update, or ASU, No. 2014-08, Reporting of Discontinued Operations and Disclosures of Disposals of Components of an Entity. We followed the held-for-sale criteria as defined in ASC 360, Property, Plant and Equipment, and ASC 205. ASC 205 requires that a component of an entity that has been disposed of or is classified as held for sale and has operations and cash flows that can be clearly distinguished from the rest of the entity be reported as assets held for sale and discontinued operations. In the period a component of an entity has been disposed of or classified as held for sale, the results of operations for the periods presented are reclassified into separate line items in the consolidated statements of operations. Assets and liabilities are also reclassified into separate line items on the related consolidated balance sheets for the periods presented. The statements of cash flows for the periods presented are also reclassified to reflect the results of discontinued operations as separate line items. ASU 2014-08 requires that only a disposal of a component of an entity, or a group of components of an entity, that represents a strategic shift that has, or will have, a major effect on the reporting entity’s operations and financial results be reported in the financial statements as discontinued operations. ASU 2014-08 also provides guidance on the financial statement presentations and disclosures of discontinued operations.

Due to the sale of our oncology business during the first quarter of 2021, in accordance with ASC 205, we have classified the results of the oncology business as discontinued operations in our consolidated statements of operations and cash flows for all periods presented, and refer to Note 15, Discontinued Operations. All amounts included in the notes to the consolidated financial statements relate to continuing operations unless otherwise noted.

Treasury stock

Treasury stock purchases are accounted for under the cost method whereby the entire cost of the acquired stock is recorded as treasury stock.

Recent accounting pronouncements

Accounting standards that have been issued by the Financial Accounting Standards Board or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on our financial statements upon adoption.

Subsequent events

We considered events or transactions occurring after the balance sheet date, but prior to the issuance of the consolidated financial statements, for potential recognition or disclosure in our consolidated financial statements. All significant subsequent events have been properly disclosed in the consolidated financial statements.

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

The following table summarizes our cash equivalents and marketable securities measured at fair value and by level (as described in Note 2, Su mmary of Significant Accounting Policies) on a recurring basis as of December 31, 2023:


(In thousands)	Level 1		Level 2		Level 3		Total
Cash equivalents	$	30,123	$	—	$	—	$	30,123
Total cash equivalents	30,123		—		—		30,123

Marketable securities:

U.S. Treasuries	—		35,652		—		35,652
Government securities	—		257,020		—		257,020
Corporate debt securities	—		425,486		—		425,486
Total marketable securities	—		718,158		—		718,158
Total cash equivalents and marketable securities	$	30,123	$	718,158	$	—	$	748,281

There were no transfers between Level 1 and Level 2 and we had no financial assets or liabilities that were classified as Level 3 at any point during the year ended December 31, 2023.

- 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

Share-Based Payments - Schedule of Company's Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Stock Options
Outstanding, beginning balance (in shares)	5,772,564
Granted (in shares)	886,795
Exercised (in shares)	(235,401)
Forfeited/expired (in shares)	(1,160,277)
Ending balance (in shares)	5,263,681	5,772,564
Exercisable (in shares)	3,344,010
Vested and expected to vest (in shares)	5,263,681
Weighted- Average Exercise Price
Outstanding, beginning balance (in usd per share)	$ 48.81
Granted (in usd per share)	25.84
Exercised (in usd per share)	12.83
Forfeited/expired (in usd per share)	56.10
Outstanding, ending balance (in usd per share)	44.94	$ 48.81
Exercise price, exercisable (in usd per share)	53.55
Vested and expected to vest (in usd per share)	$ 44.94
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average remaining contractual term, outstanding (in years)	6 years 4 months 9 days	6 years 6 months
Weighted-average remaining contractual term, exercisable (in years)	5 years 7 days
Weighted-average remaining contractual term, vested and expected to vest (in years)	6 years 4 months 9 days
Aggregate intrinsic value, outstanding	$ 423	$ 5,362
Aggregate intrinsic value, exercisable	398
Aggregate intrinsic value, vested and expected to vest	$ 423

Cover Page - USD ($)	12 Months Ended
Cover Page - USD ($)	Dec. 31, 2023	Feb. 09, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-36014
Entity Registrant Name	AGIOS PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-0662915
Entity Address, Address Line One	88 Sidney Street
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02139
City Area Code	617
Local Phone Number	649-8600
Title of 12(b) Security	Common Stock, Par Value $0.001 per share
Trading Symbol	AGIO
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction	false
Entity Shell Company	false
Entity Public Float			$ 1,557,785,326
Entity Common Stock, Shares Outstanding		56,194,847
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement for its 2024 Annual Meeting of Stockholders to be filed pursuant to Regulation 14A within 120 days of the end of the registrant’s fiscal year ended December 31, 2023 are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein.
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Central Index Key	0001439222

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 segment
Schedule of Significant Accounting Policies [Line Items]
Investment maturity period, current	1 year
Minimum period to liquidate	1 year
Number of operating segments	1
Minimum
Schedule of Significant Accounting Policies [Line Items]
Investment maturity period, current	1 year
Investment maturity period, non-current	1 year
Maximum
Schedule of Significant Accounting Policies [Line Items]
Investment maturity period, current	2 years
Investment maturity period, non-current	2 years

Share-Based Payments - Additional Information (Details) - USD ($)		12 Months Ended
	Jan. 03, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefits related to stock based compensation		$ 0	$ 0	$ 0
Expected contractual term		10 years
Expected dividend yield		0.00%	0.00%	0.00%
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period to recognize compensation expense		1 year 9 months
Unrecognized compensation expense excluding options		$ 22,600,000
Performance-based stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense excluding options		$ 0
Share-based compensation arrangement by share-based payment award, options, expected to vest, number of shares (in shares)		145,023
Unrecognized compensation cost not expected to be recognized		$ 5,900,000
Market-based stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense excluding options		$ 0
2007 Plan and 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards reserved for issuance (in shares)		12,004,551
2013 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)		4,989,341
Weighted-average grant date fair value of options (in usd per share)		$ 14.32	$ 15.64	$ 31.2
Intrinsic value of options exercised		$ 2,900,000	$ 300,000	$ 8,500,000
Unrecognized compensation expense related to options		$ 27,800,000
Weighted-average period to recognize compensation expense		2 years 4 months 24 days
2013 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)		1,686,039
Additional shares authorized for issuance (in shares)	509,091
Shares issued under 2013 ESPP (in shares)		112,832	104,867
Opportunity to purchase common stock (in shares)		2,363,636

Income Taxes - Schedule of Domestic and Foreign Components of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Domestic	$ (352,085)	$ (231,767)	$ (356,665)
Foreign	(3)	(34)	155
Net loss from continuing operations	$ (352,088)	$ (231,801)	$ (356,510)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(11))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 30
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
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-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Nature of Business (Details) $ in Thousands		12 Months Ended
Nature of Business (Details) $ in Thousands	Mar. 31, 2021 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Apr. 30, 2020 USD ($)
Subsidiary, Sale of Stock [Line Items]
Gain on sale of contingent payments		$ 0	$ 127,853	$ 0
Cash, cash equivalents and marketable securities		806,400
At-the-market Offering
Subsidiary, Sale of Stock [Line Items]
Maximum value of shares issued					$ 250,000
Value of common stock reserved for future issuance			250,000
2010 Agreement
Subsidiary, Sale of Stock [Line Items]
Milestone payment for achievement of specified ex-U.S. commercial milestone event	$ 25,000
TIBSOVO \| U.S.
Subsidiary, Sale of Stock [Line Items]
Earn-out revenue for royalties			$ 9,900	6,600
Discontinued Operations, Disposed of by Sale \| Agios Oncology Business
Subsidiary, Sale of Stock [Line Items]
Cash proceeds	1,800,000			$ 1,802,936
Contingent milestone payment	$ 200,000
Gain on sale of contingent payments		127,900
Discontinued Operations, Disposed of by Sale \| Agios Oncology Business \| TIBSOVO \| U.S.
Subsidiary, Sale of Stock [Line Items]
Contingent royalty payment	0.05
Discontinued Operations, Disposed of by Sale \| Agios Oncology Business \| vorasidenib \| U.S.
Subsidiary, Sale of Stock [Line Items]
Contingent royalty payment	0.15
Alnylam Pharmaceuticals, Inc.
Subsidiary, Sale of Stock [Line Items]
Payments for asset acquisition		17,500
Asset acquisition, contingent consideration, potential developmental and regulatory milestone payment		$ 130,000

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$ 64,066	$ 32,907
Tax credit carryforwards	180,635	163,780
Purchased intangible assets	14,155	11,583
Stock-based compensation	20,954	26,236
Operating lease liability	16,780	21,042
Non-deductible accruals and reserves, including inventory	5,134	3,992
Section 174 R&D expense	93,333	56,565
Total deferred tax assets	395,057	316,105
Depreciation and amortization	(1,986)	(3,767)
Operating lease right of use asset	(13,411)	(16,345)
Less: valuation allowance	(379,660)	(295,993)	$ (236,478)
Net deferred taxes	$ 0	$ 0

Inventory

12 Months Ended

Dec. 31, 2023

Inventory Disclosure [Abstract]

Inventory

Inventory, which consists of commercial supply of PYRUKYND®, consisted of the following:


(In thousands)	December 31, 2023		December 31, 2022
Raw materials	$	51	$	—
Work-in-process	17,568		7,550
Finished goods	1,457		942
Total inventory	$	19,076	$	8,492

Common Stock (Details)	Dec. 31, 2023 vote shares	Dec. 31, 2022 vote shares
Equity [Abstract]
Common stock, shares authorized (in shares) \| shares	125,000,000	125,000,000
Number of votes per share \| vote	1	1

Product Revenue

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Product Revenue

Product revenue, net, was as follows for the years ended December 31:


(In thousands)	2023		2022		2021
Product revenue, net	$	26,823	$	11,740	$	—

Reserves for Variable Consideration

The following tables summarize balances and activity in each of the product revenue allowance and reserve categories for the years ended December 31, 2023 and December 31, 2022:


(In thousands)	Contractual Adjustments		Government Rebates		Returns		Total
Balance at December 31, 2022	$	65	$	573	$	133	$	771
Current provisions relating to sales in the current year	1,079		2,086		2,182		5,347
Adjustments relating to prior years	—		(237)		(77)		(314)
Payments/returns relating to sales in the current year	(938)		(1,003)		(1,958)		(3,899)
Payments/returns relating to sales in the prior years	(50)		(335)		(48)		(433)
Balance at December 31, 2023	$	156	$	1,084	$	232	$	1,472


(In thousands)	Contractual Adjustments		Government Rebates		Returns		Total
Balance at December 31, 2021	$	—	$	—	$	—	$	—
Current provisions relating to sales in the current year	497		912		133		1,542
Adjustments relating to prior years	—		—		—		—
Payments/returns relating to sales in the current year	(432)		(339)		—		(771)
Payments/returns relating to sales in the prior years	—		—		—		—
Balance at December 31, 2022	$	65	$	573	$	133	$	771

Total revenue-related reserves above, included in our consolidated balance sheets, are summarized as follows:


(In thousands)	December 31, 2023		December 31, 2022
Reduction of accounts receivable	$	151	$	60
Component of accrued expenses	1,321		711
Total revenue-related reserves	$	1,472	$	771

The following table presents changes in our contract assets, which consisted of accounts receivable, net:


(In thousands)	December 31, 2023		December 31, 2022
Beginning balance	$	2,206	$	—
Additions (1)	31,855		13,283
Deductions (1)	(31,251)		(11,077)
Ending balance	$	2,810	$	2,206

(1) Additions to contract assets relate to amounts billed to Customers for product sales, and deductions to contract assets primarily relate to collection of receivables during the reporting period.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Principles of consolidation

Use of estimates

Cash and cash equivalents

We consider highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Cash equivalents are stated at fair value.

Accounts receivable, net

Inventory

Revenue recognition

Product Revenue

Cost of sales

Marketable securities

Fair value measurements

Level 1 – Unadjusted quoted prices in active markets for identical assets or liabilities.

There have been no changes to the valuation methods during the years ended December 31, 2023 and 2022. We evaluate transfers between levels at the end of each reporting period.

The carrying amounts of other receivables, prepaid expenses and other current assets, accounts payable, and accrued expenses approximate their fair values due to their short-term maturities.

Concentrations of credit risk

Property and equipment

Property and equipment is stated at cost, and depreciated using the straight-line method over the estimated useful lives of the respective assets:


						Years
Laboratory equipment						5
Computer equipment and software						3
Furniture and fixtures						5
Office equipment						5

Leasehold improvements are amortized over the lesser of the remaining lease term or the estimated useful life of the improvement.

Impairment of long-lived assets

Leases

We have not entered into any material short-term leases or financing leases as of December 31, 2023.

Research and development costs

Stock-based compensation

Income taxes

Comprehensive (loss) income

Net (loss) income per share

Segment and geographic information

Discontinued operations

Treasury stock

Treasury stock purchases are accounted for under the cost method whereby the entire cost of the acquired stock is recorded as treasury stock.

Recent accounting pronouncements

Subsequent events

Discontinued Operations

12 Months Ended

Dec. 31, 2023

Discontinued Operations and Disposal Groups [Abstract]

Discontinued Operations

On March 31, 2021, we completed the sale of our oncology business to Servier. We determined the sale of the oncology business represented a strategic shift that had a major effect on our business and therefore met the criteria for classification as discontinued operations at March 31, 2021. Accordingly, the oncology business was reported as discontinued operations in accordance with ASC 205-20, Discontinued Operations. The results of operations from the oncology business were classified as discontinued operations in the consolidated statements of operations. We recognized a gain on the sale of the oncology business upon closing.

The following table presents the gain on the sale for the year ended December 31, 2021:


(in thousands)	December 31, 2021
Cash proceeds	$	1,802,936
Less: transaction and insurance costs	(53,573)
Plus: net liabilities distributed, including working capital adjustment	239,770
Gain on sale, pre-tax	1,989,133
Income tax expense	(12,799)
Gain on sale, net of tax	$	1,976,334

As of December 31, 2023 and December 31, 2022, there were no assets or liabilities classified as discontinued operations.

The following table presents the financial results of the discontinued operations:


(in thousands)	2021
Revenues:
Product revenue, net	$	36,909
Collaboration revenue – related party	1,350
Collaboration revenue – other	491
Royalty revenue – related party	2,659
Total revenue	41,409
Cost and expenses:
Cost of sales	706
Research and development	41,564
Selling, general and administrative	8,551
Total cost and expenses	50,821
(Loss) income from discontinued operations	(9,412)
Non-cash interest expense for the sale of future revenue	(5,697)
Gain on the sale of the oncology business	1,989,133
Income from discontinued operations, pre-tax	1,974,024
Income tax expense	(12,799)
Net income from discontinued operations	$	1,961,225

In accordance with ASC 205-20, only expenses specifically identifiable and related to a business to be disposed may be presented in discontinued operations. As such, the research and development, marketing, selling and general and administrative expenses in discontinued operations include corporate costs incurred directly to solely support our oncology business.

We also entered into a Transition Services Agreement with Servier, through which we provided transitional services related to discovery, clinical development, technical operations, commercial and general and administrative related activities through March 31, 2022.

The milestone payment for approval of vorasidenib and royalty payments related to vorasidenib and TIBSOVO® represent contingent consideration. Contingent consideration has been accounted for as a gain contingency in accordance with ASC 450, Contingencies, and will be recognized in earnings in the period when realizable. As described in Note 1, Nature of Business, on October 27, 2022, we sold our rights to future contingent payments related to TIBSOVO® royalties to entities affiliated with Sagard and recognized income of $127.9 million within the gain on sale of contingent payments line item in our consolidated statements of operations for the year ended December 31, 2022.

Product Revenue - Schedule of Product Revenue Allowance and Reserves (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Contractual Adjustments
Contractual adjustments, beginning balance	$ 65	$ 0
Contractual adjustments, current provisions relating to sales in the current year	1,079	497
Contractual adjustments, adjustments relating to prior years	0	0
Contractual adjustments, payments/returns relating to sales in the current year	(938)	(432)
Contractual adjustments, payments/returns relating to sales in the prior year	(50)	0
Contractual adjustments, ending balance	156	65
Government Rebates
Government rebates, beginning balance	573	0
Government rebates, current provisions relating to sales in the current year	2,086	912
Government rebates, adjustments relating to prior years	(237)	0
Government rebates, payments/returns relating to sales in the current year	(1,003)	(339)
Government rebates, payments/returns relating to sales in the prior years	(335)	0
Government rebates, ending balance	1,084	573
Returns
Returns, beginning balance	133	0
Returns, current provisions relating to sales in the current year	2,182	133
Returns, adjustments relating to prior years	(77)	0
Returns, payments/returns relating to sales in the current year	(1,958)	0
Returns, payments/returns relating to sales in the prior years	(48)	0
Returns, ending balance	232	133
Total
Total revenue-related reserves	1,472	771	$ 0
Total allowances and reserves, current provisions relating to sales in the current year	5,347	1,542
Total allowances and reserves, adjustments relating to prior years	(314)	0
Total allowances and reserves, payments/returns relating to sales in the current year	(3,899)	(771)
Total allowances and reserves, payments/returns relating to sales in the prior years	$ (433)	$ 0

Property and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Summary of Property and Equipment

Property and equipment, net consisted of the following at December 31:


(In thousands)	2023		2022
Laboratory equipment	$	17,433	$	23,182
Computer equipment and software	6,566		6,179
Leasehold improvements	37,277		37,277
Furniture and fixtures	3,459		3,514
Office equipment	2,268		2,248
Construction in progress	608		657
Total property and equipment	67,611		73,057
Less: accumulated depreciation	(52,229)		(50,070)
Total property and equipment, net	$	15,382	$	22,987

Share-Based Payments - Schedule of Grant Date Fair Value Option Award Weighted Average Assumptions Used (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Risk-free interest rate	4.05%	2.55%	0.72%
Expected dividend yield	0.00%	0.00%	0.00%
Expected term (in years)	5 years 11 months 26 days	6 years 10 days	6 years 18 days
Expected volatility	54.26%	55.30%	61.72%

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Total revenue	$ 26,823	$ 14,240	$ 0
Operating expenses
Cost of sales	2,881	1,704	0
Research and development	295,526	279,910	256,973
Selling, general and administrative	119,903	121,673	121,445
Total operating expenses	418,310	403,287	378,418
Loss from operations	(391,487)	(389,047)	(378,418)
Gain on sale of contingent payments	0	127,853	0
Royalty income from gain on sale of oncology business	0	9,851	6,639
Interest income, net	33,344	12,793	836
Other income, net	6,055	6,749	14,433
Net loss from continuing operations	(352,088)	(231,801)	(356,510)
Net income from discontinued operations, net of tax	0	0	1,961,225
Net (loss) income	$ (352,088)	$ (231,801)	$ 1,604,715
Net loss from continuing operations per share - basic (in usd per share)	$ (6.33)	$ (4.23)	$ (5.90)
Net loss from continuing operations per share - diluted (in usd per share)	(6.33)	(4.23)	(5.90)
Net income from discontinued operations per share - basic (in usd per share)	0	0	32.45
Net income from discontinued operations per share - diluted (in usd per share)	0	0	32.45
Net (loss) income per share - basic (in usd per share)	(6.33)	(4.23)	26.55
Net (loss) income per share - diluted (in usd share)	$ (6.33)	$ (4.23)	$ 26.55
Weighted-average number of common shares used in computing net loss per share from continuing operations, net income per share from discontinued operations and net (loss) income per share – basic (in shares)	55,651,487	54,789,435	60,447,346
Weighted-average number of common shares used in computing net loss per share from continuing operations, net income per share from discontinued operations and net (loss) income per share – diluted (in shares)	55,651,487	54,789,435	60,447,346
Product revenue, net
Revenues:
Total revenue	$ 26,823	$ 11,740	$ 0
Milestone revenue
Revenues:
Total revenue	$ 0	$ 2,500	$ 0

Inventory (Tables)

12 Months Ended

Dec. 31, 2023

Inventory Disclosure [Abstract]

Schedule of Inventory

Inventory, which consists of commercial supply of PYRUKYND®, consisted of the following:


(In thousands)	December 31, 2023		December 31, 2022
Raw materials	$	51	$	—
Work-in-process	17,568		7,550
Finished goods	1,457		942
Total inventory	$	19,076	$	8,492

Discontinued Operations (Tables)

12 Months Ended

Dec. 31, 2023

Discontinued Operations and Disposal Groups [Abstract]

Disposal Groups, Including Discontinued Operations

The following table presents the gain on the sale for the year ended December 31, 2021:


(in thousands)	December 31, 2021
Cash proceeds	$	1,802,936
Less: transaction and insurance costs	(53,573)
Plus: net liabilities distributed, including working capital adjustment	239,770
Gain on sale, pre-tax	1,989,133
Income tax expense	(12,799)
Gain on sale, net of tax	$	1,976,334

The following table presents the financial results of the discontinued operations:


(in thousands)	2021
Revenues:
Product revenue, net	$	36,909
Collaboration revenue – related party	1,350
Collaboration revenue – other	491
Royalty revenue – related party	2,659
Total revenue	41,409
Cost and expenses:
Cost of sales	706
Research and development	41,564
Selling, general and administrative	8,551
Total cost and expenses	50,821
(Loss) income from discontinued operations	(9,412)
Non-cash interest expense for the sale of future revenue	(5,697)
Gain on the sale of the oncology business	1,989,133
Income from discontinued operations, pre-tax	1,974,024
Income tax expense	(12,799)
Net income from discontinued operations	$	1,961,225

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
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-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-3

+ Details

Discontinued Operations - Financial Results of Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cost and expenses:
Net income from discontinued operations	$ 0	$ 0	$ 1,961,225
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue			41,409
Cost and expenses:
Cost of sales			706
Research and development			41,564
Selling, general and administrative			8,551
Total cost and expenses			50,821
(Loss) income from discontinued operations			(9,412)
Non-cash interest expense for the sale of future revenue			(5,697)
Gain on the sale of the oncology business			1,989,133
Income from discontinued operations, pre-tax			1,974,024
Income tax expense			(12,799)
Net income from discontinued operations			1,961,225
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale \| Product revenue, net
Revenues:
Total revenue			36,909
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale \| Collaboration revenue – related party
Revenues:
Total revenue			1,350
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale \| Collaboration revenue – other
Revenues:
Total revenue			491
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale \| Royalty revenue – related party
Revenues:
Total revenue			$ 2,659

Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials	$ 51	$ 0
Work-in-process	17,568	7,550
Finished goods	1,457	942
Total inventory	$ 19,076	$ 8,492

Property and Equipment, net - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 6.6	$ 8.4	$ 8.8

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities
Net (loss) income	$ (352,088)	$ (231,801)	$ 1,604,715
Less: Net income from discontinued operations	0	0	1,961,225
Net loss from continuing operations	(352,088)	(231,801)	(356,510)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	6,623	8,564	9,240
Stock-based compensation expense	44,766	49,296	53,508
Net (accretion of discount) amortization of premium on marketable securities	(5,051)	(1,198)	6,949
Gain on sale of contingent payments	0	(127,853)	0
Loss (gain) on disposal of property and equipment	553	(48)	12
Non-cash operating lease expense	10,720	9,995	9,537
Expense associated with license agreement	17,500	0	0
Realized gain on investments	(28)	0	0
Changes in operating assets and liabilities:
Accounts receivable, net	(604)	(2,206)	0
Inventory	(10,584)	(8,492)	0
Other receivables	0	447	(4,378)
Prepaid expenses and other current and non-current assets	3,833	(176)	(26,846)
Accounts payable	(8,733)	3,436	1,863
Accrued expenses	12,817	(1,617)	66
Operating lease liabilities	(13,663)	(10,828)	(7,527)
Other liabilities	(2,123)	3,003	0
Net cash used in operating activities - continuing operations	(296,062)	(309,478)	(314,086)
Net cash used in operating activities - discontinued operations	0	0	(93,234)
Net cash used in operating activities	(296,062)	(309,478)	(407,320)
Investing activities
Purchases of marketable securities	(417,930)	(1,030,781)	(1,378,221)
Proceeds from maturities and sales of marketable securities	674,679	1,146,175	829,804
Proceeds from sale of contingent payments	0	131,784	0
Payments associated with license agreement	(17,500)	0	0
Purchases of property and equipment	(999)	(4,881)	(5,741)
Proceeds from sale of equipment	1,325	964	0
Net cash provided by (used in) investing activities - continuing operations	239,575	243,261	(554,158)
Net cash provided by investing activities - discontinued operations	0	0	1,802,936
Net cash provided by investing activities	239,575	243,261	1,248,778
Financing activities
Payments on financing lease obligations	0	(331)	(578)
Purchase of treasury stock	0	0	(802,486)
Net proceeds from stock option exercises and employee stock purchase plan	5,433	2,681	37,296
Net cash provided by (used in) financing activities	5,433	2,350	(765,768)
Net change in cash and cash equivalents	(51,054)	(63,867)	75,690
Cash and cash equivalents at beginning of the period	139,259	203,126	127,436
Cash and cash equivalents at end of the period	88,205	139,259	203,126
Supplemental disclosure of non-cash investing and financing transactions:
Additions to property and equipment in accounts payable and accrued expenses	55	158	1,678
Net cash taxes paid	1,569	0	16,078
Financing lease liabilities arising from obtaining financing lease assets	$ 0	$ 0	$ 511

Product Revenue - Schedule of Product Revenue, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenue	$ 26,823	$ 14,240	$ 0
Product revenue, net
Disaggregation of Revenue [Line Items]
Total revenue	$ 26,823	$ 11,740	$ 0

- Definition

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

+ References + Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479941/924-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details

Net Income (Loss) per Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Net Income (Loss) per Share

Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted-average shares outstanding during the period, without consideration for common stock equivalents. Diluted net income (loss) per share is calculated by adjusting the weighted-average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury stock method. For purposes of the dilutive net income (loss) per share calculation, stock options, RSUs, PSUs and MSUs for which the performance and market vesting conditions, respectively, have been deemed probable, and 2013 ESPP shares are considered to be common stock equivalents, while PSUs and MSUs with performance and market vesting conditions, respectively, that were not deemed probable as of December 31, 2023 are not considered to be common stock equivalents.

We utilize the control number concept in the computation of diluted earnings per share to determine whether potential common stock equivalents are dilutive. The control number used is net loss from continuing operations. The control number concept requires that the same number of potentially dilutive securities applied in computing diluted earnings per share from continuing operations be applied to all other categories of income or loss, regardless of their anti-dilutive effect on such categories. Since we had a net loss from continuing operations for all periods presented, no dilutive effect has been recognized in the calculation of income (loss) from discontinued operations per share or net income (loss) per share. Basic and diluted net income (loss) per share was the same for all periods presented.

The following common stock equivalents were excluded from the calculation of diluted net loss per share applicable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:


	Years ended December 31,
	2023	2022	2021
Stock options	5,263,681	5,772,564	4,798,826
Restricted stock units	1,346,701	1,117,921	1,002,924
Performance-based stock units	145,023	—	—
Employee Stock Purchase Plan shares	48,713	42,026	39,864
Total	6,804,118	6,932,511	5,841,614

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	25,000,000	25,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	125,000,000	125,000,000
Common stock, issued (in shares)	72,161,489	71,256,118
Common stock, outstanding (in shares)	55,945,078	55,039,707
Treasury stock (in shares)	16,216,411	16,216,411

Product Revenue (Tables)

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Schedule of Product Revenue

Product revenue, net, was as follows for the years ended December 31:


(In thousands)	2023		2022		2021
Product revenue, net	$	26,823	$	11,740	$	—

Schedule of Product Revenue Allowance and Reserves

The following tables summarize balances and activity in each of the product revenue allowance and reserve categories for the years ended December 31, 2023 and December 31, 2022:


(In thousands)	Contractual Adjustments		Government Rebates		Returns		Total
Balance at December 31, 2022	$	65	$	573	$	133	$	771
Current provisions relating to sales in the current year	1,079		2,086		2,182		5,347
Adjustments relating to prior years	—		(237)		(77)		(314)
Payments/returns relating to sales in the current year	(938)		(1,003)		(1,958)		(3,899)
Payments/returns relating to sales in the prior years	(50)		(335)		(48)		(433)
Balance at December 31, 2023	$	156	$	1,084	$	232	$	1,472


(In thousands)	Contractual Adjustments		Government Rebates		Returns		Total
Balance at December 31, 2021	$	—	$	—	$	—	$	—
Current provisions relating to sales in the current year	497		912		133		1,542
Adjustments relating to prior years	—		—		—		—
Payments/returns relating to sales in the current year	(432)		(339)		—		(771)
Payments/returns relating to sales in the prior years	—		—		—		—
Balance at December 31, 2022	$	65	$	573	$	133	$	771

Schedule of Revenue Related Reserves

Total revenue-related reserves above, included in our consolidated balance sheets, are summarized as follows:


(In thousands)	December 31, 2023		December 31, 2022
Reduction of accounts receivable	$	151	$	60
Component of accrued expenses	1,321		711
Total revenue-related reserves	$	1,472	$	771

Schedule of Changes in Contract Assets

The following table presents changes in our contract assets, which consisted of accounts receivable, net:


(In thousands)	December 31, 2023		December 31, 2022
Beginning balance	$	2,206	$	—
Additions (1)	31,855		13,283
Deductions (1)	(31,251)		(11,077)
Ending balance	$	2,810	$	2,206

(1) Additions to contract assets relate to amounts billed to Customers for product sales, and deductions to contract assets primarily relate to collection of receivables during the reporting period.

Leases

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Leases

Our building leases are comprised of office and laboratory space under non-cancelable operating leases. These lease agreements have remaining lease terms of four years and contain various clauses for renewal at our option. The renewal options were not included in the calculation of the operating lease assets and the operating lease liabilities as the renewal options are not reasonably certain of being exercised. The lease agreements do not contain residual value guarantees.

We currently lease approximately 146,000 square feet at 88 Sidney Street, 43,000 square feet at 64 Sidney Street, and 13,000 square feet at 38 Sidney Street, Cambridge, Massachusetts. All leases, as amended, expire on February 29, 2028. At the end of the initial lease period, we have the option to extend the leases at all facilities for two consecutive five-year periods at the fair market rent at the time of the extension.

The components of lease expense and other information related to leases were as follows:


(In thousands)	2023		2022		2021
Operating lease costs	$	15,227	$	15,227	$	15,229
Cash paid for amounts included in the measurement of operating lease liabilities	18,170		17,035		14,411

We have not entered into any material short-term leases or financing leases as of December 31, 2023.

In arriving at the operating lease liabilities as of December 31, 2023, we applied the weighted-average incremental borrowing rate of 5.7% from inception over a weighted-average remaining lease term of 4.2 years. In arriving at the operating lease liabilities as of December 31, 2022, we applied the weighted-average incremental borrowing rate of 5.7% over a weighted-average remaining lease term of 5.2 years.

As of December 31, 2023, undiscounted minimum rental commitments under non-cancelable leases, for each of the next five years and total thereafter, were as follows:


(In thousands)
2024	$	17,142
2025	19,506
2026	20,151
2027	20,755
2028	3,479
Thereafter	—
Undiscounted minimum rental commitments	81,033
Interest	(9,037)
Total operating lease liabilities	$	71,996

We provided our landlord a security deposit of $2.9 million as security for our leases, which is included within other non-current assets on our consolidated balance sheet.

In August 2021, we entered into a long-term sublease agreement for 13,000 square feet of the office space at 38 Sidney Street, Cambridge, Massachusetts, with the term of the lease running through December 2024. In April 2022, we entered into a long-term sublease agreement for 27,000 square feet of the office space at 64 Sidney Street, Cambridge, Massachusetts, with the term of the lease running through April 2025. At the end of the initial sublease periods, the subtenant has the option to extend the leases for one additional 6-month period.

In May 2023, we entered into a long-term sublease agreement for 7,407 square feet of office space on the first floor of 64 Sidney Street, Cambridge, Massachusetts, with the term of the lease running through April 2025. At the end of the initial sublease period, the subtenant has the option to extend the lease for one additional year, followed by a second extension option for twenty-two additional months.

We recorded operating sublease income of $6.1 million and $4.1 million for the years ended December 31, 2023 and December 31, 2022, respectively, in other income, net in the consolidated statements of operations. We received a security deposit from our sublessee of approximately $1.2 million which is recorded within other non-current assets on our consolidated balance sheet.

As of December 31, 2023, the future minimum lease payments to be received under the long-term sublease agreements were as follows:


(In thousands)
2024	5,078
2025	1,310

Total	$	6,388

Share-Based Payments

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Share-Based Payments

2023 Stock Incentive Plan and Inducement Grants

In June 2023, our stockholders approved the 2023 Stock Incentive Plan, or the 2023 Plan. The 2023 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock units, or RSUs, performance-based share units, or PSUs, and other stock-based awards to employees, advisors, consultants and non-employee directors.

Following the adoption of the 2023 Plan, we ceased granting equity awards under the 2013 Stock Incentive Plan, or the 2013 Plan. Any outstanding equity awards that were previously granted under the 2013 Plan continue to be governed by their terms. Following adoption of the 2013 Plan, we ceased granting equity awards under the 2007 Stock Incentive Plan, or the 2007 Plan. There are no outstanding equity awards under the 2007 Plan.

In connection with the start of employment of our Chief Executive Officer and Chief Financial Officer in 2022, and our Chief Commercial Officer in 2023, our board of directors granted each of them equity awards in the form of stock options, RSUs and PSUs, which awards were made outside our equity incentive plans as inducements material to their respective entry into employment with us in accordance with Nasdaq Listing Rule 5635(c)(4).

As of December 31, 2023, the maximum number of shares reserved under the 2013 Plan, the 2023 Plan and the inducement grants described above was 12,004,551, and we had 4,989,341 shares available for future issuance under the 2023 Plan.

Stock options

The following table summarizes the stock option activity of all stock incentive plans for the year ended December 31, 2023:


	Number of Stock Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2022	5,772,564	$	48.81	6.50	$	5,362
Granted	886,795	25.84
Exercised	(235,401)	12.83
Forfeited/Expired	(1,160,277)	56.10
Outstanding at December 31, 2023	5,263,681	$	44.94	6.36	$	423
Exercisable at December 31, 2023	3,344,010	$	53.55	5.02	$	398
Vested and expected to vest at December 31, 2023	5,263,681	$	44.94	6.36	$	423

The weighted-average grant date fair value of options granted was $14.32, $15.64 and $31.20 during the years ended December 31, 2023, 2022 and 2021, respectively. The total intrinsic value of options exercised was $2.9 million, $0.3 million and $8.5 million during the years ended December 31, 2023, 2022 and 2021, respectively.

At December 31, 2023, the total unrecognized compensation expense related to unvested stock option awards was $27.8 million, which we expect to recognize over a weighted-average period of approximately 2.40 years.

Restricted stock units

Upon vesting, each RSU entitles the holder to receive a specified number of shares of our common stock. The following table presents RSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	1,117,921	$	38.30
Granted	914,943	25.93
Vested	(464,881)	41.36
Forfeited	(221,282)	33.25
Unvested shares at December 31, 2023	1,346,701	$	29.67

As of December 31, 2023, there was approximately $22.6 million of total unrecognized compensation expense related to RSUs, which we expect to be recognized over a weighted-average period of 1.75 years.

Performance-based stock units

At the achievement of the performance-based and service-based vesting criteria, each PSU entitles the holder to receive a specified number of shares of our common stock. The following table presents PSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	430,243	$	35.87
Granted	125,897	25.23
Vested	(92,257)	30.18
Forfeited	(101,750)	46.39

Unvested shares at December 31, 2023	362,133	$	30.66

Included in unvested shares were 145,023 shares with performance-based vesting criteria that were considered probable of achievement at December 31, 2023 and vested in January 2024. Stock-based compensation expense associated with these PSUs is recognized if the underlying performance condition is considered probable of achievement using our management’s best estimates. As of December 31, 2023, there was no unrecognized compensation expense related to PSUs with performance-

based vesting criteria that are considered probable of achievement that we expect to recognize. There is $5.9 million of total unrecognized compensation expense related to PSUs with performance-based vesting criteria that are considered not probable of achievement.

Market-based stock units

We have issued certain equity awards that contain market based vesting conditions, in which shares of stock are earned at vesting based on stock price performance. The fair value of MSUs are estimated using a Monte Carlo simulation model. Assumptions and estimates utilized in the model include the risk-free interest rate, dividend yield, expected stock volatility and the estimated period to achievement of the market condition.

The following table presents MSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	42,695	$	41.50
Granted	—	—
Unvested shares at December 31, 2023	42,695	$	41.50

As of December 31, 2023, there was no remaining unrecognized compensation expense related to MSUs.

2013 Employee Stock Purchase Plan

In June 2013, our Board of Directors adopted, and in July 2013 our stockholders approved, the 2013 Employee Stock Purchase Plan, or the 2013 ESPP. On January 1, 2023, the annual increase for the 2013 ESPP resulted in an additional 509,091 shares authorized for issuance. We issued 112,832 shares and 104,867 shares during the years ended December 31, 2023 and 2022, respectively, under the 2013 ESPP. The 2013 ESPP provides participating employees with the opportunity to purchase up to an aggregate of 2,363,636 shares of our common stock. As of December 31, 2023, we had 1,686,039 shares available for future issuance under the 2013 ESPP.

Stock-based compensation expense

During the years ended December 31, 2023, 2022 and 2021, we recorded stock-based compensation expense for employee and non-employee stock options, RSUs, PSUs, and ESPP shares. Stock-based compensation expense by award type included within the consolidated statements of operations is as follows:


(In thousands)	2023		2022		2021
Stock options	$	17,163	$	23,731	$	30,985
Restricted stock units	19,367		21,670		21,510
Performance-based stock units	7,368		2,919		—
Employee Stock Purchase Plan	868		976		1,013

Total stock-based compensation expense	$	44,766	$	49,296	$	53,508

Expenses related to equity-based awards were allocated as follows in the consolidated statements of operations:


(In thousands)	2023		2022		2021
Research and development expense	$	17,064	$	20,988	$	24,527
Selling, general and administrative expense	27,702		28,308		28,981
Total stock-based compensation expense	$	44,766	$	49,296	$	53,508

No related tax benefits were recognized for the years ended December 31, 2023, 2022 and 2021.

The fair value of each stock option granted to employees and non-employees is estimated on the date of grant using the Black-Scholes option-pricing model. The following table summarizes the weighted average assumptions used in calculating the grant date fair value of the awards:


	2023		2022		2021
Risk-free interest rate	4.05	%	2.55	%	0.72	%
Expected dividend yield	—		—		—
Expected term (in years)	5.99		6.03		6.05
Expected volatility	54.26	%	55.30	%	61.72	%

Expected term

We use the “simplified method” as prescribed by the Securities and Exchange Commission Staff Accounting Bulletin No. 107, Share Based Payments, to estimate the expected term of stock option grants. Under this approach, the weighted-average expected life is presumed to be the average of the contractual term of ten years and the weighted-average vesting term of the stock options, taking into consideration multiple vesting tranches. We utilize this method due to the plain-vanilla nature of our share-based awards.

Volatility

The expected volatility has been determined using our historical volatilities for a period equal to the expected term of the option grant.

Risk-free rate

The risk-free rate is based on the yield curve of U.S. Treasury securities with periods commensurate with the expected term of the options being valued.

Dividends

We have never paid, and do not anticipate paying, any cash dividends in the foreseeable future, and, therefore, use an expected dividend yield of zero in the option-pricing model.

Forfeitures

We account for forfeitures as they occur and, therefore, do not estimate forfeitures.

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Summary of Cash Equivalents and Marketable Securities Measured at Fair Value on a Recurring Basis


(In thousands)	Level 1		Level 2		Level 3		Total
Cash equivalents	$	30,123	$	—	$	—	$	30,123
Total cash equivalents	30,123		—		—		30,123

Marketable securities:

U.S. Treasuries	—		35,652		—		35,652
Government securities	—		257,020		—		257,020
Corporate debt securities	—		425,486		—		425,486
Total marketable securities	—		718,158		—		718,158
Total cash equivalents and marketable securities	$	30,123	$	718,158	$	—	$	748,281

Defined Contribution Benefit Plan (Details)	12 Months Ended
Defined Contribution Benefit Plan (Details)	Dec. 31, 2023
Retirement Benefits [Abstract]
Employer's matching contribution percentage	100.00%
Employer's contribution percentage of eligible compensation	4.00%

Defined Contribution Benefit Plan	12 Months Ended
Defined Contribution Benefit Plan	Dec. 31, 2023
Retirement Benefits [Abstract]
Defined Contribution Benefit Plan	Defined Contribution Benefit Plan We sponsor a 401(k) retirement plan, in which substantially all of our full-time employees are eligible to participate. Participants may contribute a percentage of their annual compensation to this plan, subject to statutory limitations. We will make matching contributions equal to 100% of the employee’s contributions, subject to a maximum of 4% of eligible compensation.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

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-Topic 715
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Topic 715
-SubTopic 20
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-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
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-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Leases - Schedule of Future Minimum Lease Payments to be Received under the Long-term Sublease Agreements (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 5,078
2025	1,310
Total	$ 6,388

Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Details)	Dec. 31, 2023
Laboratory equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment (in years)	5 years
Computer equipment and software
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment (in years)	3 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment (in years)	5 years
Office equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment (in years)	5 years

Net Income (Loss) per Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Schedule of Common Stock Excluded from Calculation of Diluted Earnings Per Share


	Years ended December 31,
	2023	2022	2021
Stock options	5,263,681	5,772,564	4,798,826
Restricted stock units	1,346,701	1,117,921	1,002,924
Performance-based stock units	145,023	—	—
Employee Stock Purchase Plan shares	48,713	42,026	39,864
Total	6,804,118	6,932,511	5,841,614

Leases - Schedule of Undiscounted Minimum Rental Commitments under Non-cancelable Leases (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 17,142
2025	19,506
2026	20,151
2027	20,755
2028	3,479
Thereafter	0
Undiscounted minimum rental commitments	81,033
Interest	(9,037)
Total operating lease liabilities	$ 71,996

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net (loss) income	$ (352,088)	$ (231,801)	$ 1,604,715

- Definition

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

+ References

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+ Details

Leases - Additional Information (Details) $ in Millions	1 Months Ended		12 Months Ended
Leases - Additional Information (Details) $ in Millions	May 31, 2023 ft²	Apr. 30, 2022 ft² extension	Dec. 31, 2023 USD ($) ft² leaseTerm	Dec. 31, 2022 USD ($)	Aug. 31, 2021 ft²
Lessee, Lease, Description [Line Items]
Remaining lease terms			4 years
Weighted-average incremental borrowing rate			5.70%	5.70%
Weighted-average remaining lease term			4 years 2 months 12 days	5 years 2 months 12 days
Sublease income \| $			$ 6.1	$ 4.1
Other Noncurrent Assets
Lessee, Lease, Description [Line Items]
Standby letter of credit \| $			2.9
Security deposit liability \| $			$ 1.2
88 Sidney Street Lease
Lessee, Lease, Description [Line Items]
Number of square feet of office space (in square feet)			146,000
Number of optional terms available at end of current lease term (in lease terms) \| leaseTerm			2
Term for extension of operating lease (in years)			5 years
64 Sidney Street Lease
Lessee, Lease, Description [Line Items]
Number of square feet of office space (in square feet)			43,000
Number of optional terms available at end of current lease term (in lease terms) \| leaseTerm			2
Term for extension of operating lease (in years)			5 years
Area of premises subleased (in square feet)	7,407	27,000
Number of extension periods \| extension		1
Extension period	1 year	6 months
Second extension period	22 months
38 Sidney Street Lease
Lessee, Lease, Description [Line Items]
Number of square feet of office space (in square feet)			13,000
Number of optional terms available at end of current lease term (in lease terms) \| leaseTerm			2
Term for extension of operating lease (in years)			5 years
Area of premises subleased (in square feet)					13,000

Commitments and Contingent Liabilities (Details)	Dec. 31, 2023 lawsuit
Commitments and Contingencies Disclosure [Abstract]
Number of ongoing legal proceedings	0

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Estimated Useful Lives of Property and Equipment

Property and equipment is stated at cost, and depreciated using the straight-line method over the estimated useful lives of the respective assets:


						Years
Laboratory equipment						5
Computer equipment and software						3
Furniture and fixtures						5
Office equipment						5

Share-Based Payments - Schedule of Expenses Related to Stock Options and Stock-based Awards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense	$ 44,766	$ 49,296	$ 53,508
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense	17,064	20,988	24,527
Selling, general and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense	$ 27,702	$ 28,308	$ 28,981

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Schedule of Lease Cost and Other Information

The components of lease expense and other information related to leases were as follows:


(In thousands)	2023		2022		2021
Operating lease costs	$	15,227	$	15,227	$	15,229
Cash paid for amounts included in the measurement of operating lease liabilities	18,170		17,035		14,411

Schedule of Undiscounted Minimum Rental Commitments

As of December 31, 2023, undiscounted minimum rental commitments under non-cancelable leases, for each of the next five years and total thereafter, were as follows:


(In thousands)
2024	$	17,142
2025	19,506
2026	20,151
2027	20,755
2028	3,479
Thereafter	—
Undiscounted minimum rental commitments	81,033
Interest	(9,037)
Total operating lease liabilities	$	71,996

Schedule of Future Minimum Lease Payments to be Received

As of December 31, 2023, the future minimum lease payments to be received under the long-term sublease agreements were as follows:


(In thousands)
2024	5,078
2025	1,310

Total	$	6,388

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Share Repurchase Program	12 Months Ended
Share Repurchase Program	Dec. 31, 2023
Equity [Abstract]
Share Repurchase Program	Share Repurchase Program On March 25, 2021, we announced that our board of directors authorized a repurchase program, or the Repurchase Program, for the repurchase of up to $1.2 billion of our outstanding shares of common stock. On March 31, 2021, in connection with the Repurchase Program, we entered into a definitive share repurchase agreement with BMS to repurchase 7.1 million shares of our common stock held by certain subsidiaries of BMS for an aggregate purchase price of $344.5 million, or $48.38 per share. This repurchase was completed on April 5, 2021. Further, on April 2, 2021, in connection with the Repurchase Program, we entered into a Rule 10b5-1 repurchase plan to which we may repurchase up to $600.0 million of shares of our common stock. As of December 31, 2023, we repurchased approximately 9.1 million shares of common stock for $458.0 million, or $50.35 per share, under the Rule 10b5-1 repurchase plan. In total, as of December 31, 2023, we repurchased 16.2 million shares of common stock for $802.5 million, or $49.49 per share, under the Repurchase Program. No common stock was purchased during the years ended December 31, 2023 or December 31, 2022. On October 5, 2021, we terminated our Rule 10b5-1 share repurchase plan and on October 13, 2021, we entered into a Rule 10b-18 repurchase plan that allows us to conduct open market repurchases over time up to our remaining authorization under the Repurchase Program. We have paused our share repurchases for the foreseeable future. Repurchased shares are held as treasury stock until they are retired or re-issued. Treasury stock purchases are accounted for under the cost method whereby the entire cost of the acquired stock is recorded as treasury stock. Repurchases of our common stock are accounted for as of the settlement date. There were no retirements or re-issuances of treasury stock during the year ended December 31, 2023.

Commitments and Contingent Liabilities	12 Months Ended
Commitments and Contingent Liabilities	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Commitments and Contingent Liabilities Manufacturing Commitments We are party to various agreements with contract manufacturing organizations that we are not contractually able to terminate for convenience and avoid any and all future obligations to the vendors. Under such agreements, we are obligated to make certain minimum payments, with the exact amounts in the event of termination to be based on the timing of the termination and the exact terms of the agreement. Legal Contingencies From time to time, we may be involved in disputes and legal proceedings in the ordinary course of business. These proceedings may include allegations of infringement of intellectual property, employment or other matters. We do not have any ongoing legal proceedings that, based on our estimates, could have a material effect on our consolidated financial statements.

Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (352,088)	$ (231,801)	$ 1,604,715
Other comprehensive (loss) income
Unrealized gain (loss) on available-for-sale securities	12,094	(11,337)	(1,303)
Comprehensive (loss) income	$ (339,994)	$ (243,138)	$ 1,603,412

- Definition

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

+ References

+ Details

Income Taxes - Additional Information (Details)	12 Months Ended
Income Taxes - Additional Information (Details)	Dec. 31, 2023 USD ($) audit	Dec. 31, 2022 USD ($) audit	Dec. 31, 2021 USD ($) audit
Income Taxes Disclosure [Line Items]
Capitalized research and development costs	$ 232,700,000	$ 261,400,000
Percentage of stock owned resulting in an ownership change	50.00%
Aggregate period	3 years
Valuation allowance	$ 379,660,000	295,993,000	$ 236,478,000
Increase (decrease) for the current period	83,667,000	59,515,000
Accrued interest and penalties related to uncertain tax positions	0	0
Unrecognized tax benefits	$ 28,578,000	$ 26,190,000	$ 24,220,000
Number of federal, state or foreign audits in process \| audit	0	0	0
Prepaid Expenses and Other Current Assets
Income Taxes Disclosure [Line Items]
Income tax receivable	$ 1,100,000	$ 300,000
Federal Orphan Drug Tax Credit
Income Taxes Disclosure [Line Items]
Research and development tax credit	132,900,000
Federal
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards	131,700,000
Federal \| Research Tax Credit Carryforward
Income Taxes Disclosure [Line Items]
Research and development tax credit	25,500,000
State and Local Jurisdiction
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards	502,400,000
State and Local Jurisdiction \| Research Tax Credit Carryforward
Income Taxes Disclosure [Line Items]
Research and development tax credit	28,100,000
Foreign Income Tax
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards	$ 65,200,000
U.S.
Income Taxes Disclosure [Line Items]
Capitalized research and development costs, amortization period	5 years
Non-US
Income Taxes Disclosure [Line Items]
Capitalized research and development costs, amortization period	15 years

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 88,205	$ 139,259
Marketable securities	688,723	643,860
Accounts receivable, net	2,810	2,206
Inventory	19,076	8,492
Prepaid expenses and other current assets	35,021	38,955
Total current assets	833,835	832,772
Marketable securities	29,435	313,874
Operating lease assets	54,409	65,129
Property and equipment, net	15,382	22,987
Other non-current assets	4,057	3,956
Total assets	937,118	1,238,718
Current liabilities:
Accounts payable	9,780	18,616
Accrued expenses	43,167	30,350
Operating lease liabilities	15,008	13,663
Total current liabilities	67,955	62,629
Operating lease liabilities, net of current portion	56,988	71,996
Other non-current liabilities	1,156	3,279
Total liabilities	126,099	137,904
Commitments and contingent liabilities (Note 16)
Stockholders’ equity:
Preferred stock, $0.001 par value; 25,000,000 shares authorized, no shares issued and outstanding at December 31, 2023 and 2022	0	0
Common stock, $0.001 par value; 125,000,000 shares authorized; 72,161,489 shares issued and 55,945,078 outstanding at December 31, 2023 and 71,256,118 shares issued and 55,039,707 outstanding at December 31, 2022	72	71
Additional paid-in capital	2,436,523	2,386,325
Accumulated other comprehensive loss	(441)	(12,535)
Accumulated deficit	(822,649)	(470,561)
Treasury stock, at cost (16,216,411 shares at December 31, 2023 and December 31, 2022)	(802,486)	(802,486)
Total stockholders’ equity	811,019	1,100,814
Total liabilities and stockholders’ equity	$ 937,118	$ 1,238,718

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

The domestic and foreign components of loss from continuing operations before income taxes are as follows:


(In thousands)	2023		2022		2021
Domestic	$	(352,085)	$	(231,767)	$	(356,665)
Foreign	(3)		(34)		155
Total	$	(352,088)	$	(231,801)	$	(356,510)

We did not have any provision for income taxes for the years ended December 31, 2023, 2022 and 2021.

A reconciliation of the expected income tax benefit (expense) computed using the federal statutory income tax rate to our effective income tax rate is as follows for the years ended December 31, 2023, 2022 and 2021:


	2023		2022		2021
Income tax benefit computed at federal statutory tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	1.9	%	2.9	%	2.6	%
Change in valuation allowance	(23.8)	%	(25.7)	%	(24.5)	%
General business credits and other credits	4.2	%	5.2	%	5.3	%
Permanent differences and other adjustments	(2.8)	%	(2.3)	%	(3.9)	%
Stock based compensation	(0.5)	%	(1.1)	%	(0.5)	%


Total	—	%	—	%	—	%

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of our deferred tax assets and liabilities for the years ended December 31, 2023 and 2022 are as follows:


(In thousands)	2023		2022
Deferred tax assets:
Net operating loss carryforwards	$	64,066	$	32,907

Tax credit carryforwards	180,635		163,780
Purchased intangible assets	14,155		11,583
Stock-based compensation	20,954		26,236
Operating lease liability	16,780		21,042
Non-deductible accruals and reserves, including inventory	5,134		3,992
Section 174 R&D expense	93,333		56,565

Total deferred tax assets	395,057		316,105
Depreciation and amortization	(1,986)		(3,767)
Operating lease right of use asset	(13,411)		(16,345)
Less: valuation allowance	(379,660)		(295,993)
Net deferred taxes	$	—	$	—

The Tax Cuts and Jobs Act (TCJA) requires taxpayers to capitalize and amortize research and experimental expenditures under Internal Revenue Code section 174 for tax years beginning after December 31, 2021. The Company capitalized research and experimental costs of $232.7 million and $261.4 million for the years ended December 31, 2023 and December 31, 2022, respectively. We will amortize these costs for tax purposes over 5 years if the research and experimentation was performed in the U.S. and over 15 years if the research and experimentation was performed outside the U.S.

As of December 31, 2023, we had net operating loss carryforwards, or NOLs, available to reduce federal, state and foreign income taxes of approximately $131.7 million, $502.4 million and $65.2 million, respectively. At December 31, 2023, we also had available research and development tax credits for federal and state income tax purposes of approximately $25.5 million and $28.1 million, respectively. If not utilized, the credits begin to expire in 2039 and 2027 for federal and state income tax purposes, respectively. We engaged in clinical testing activities and incurred expenses that qualify for the federal orphan drug tax credit. At December 31, 2023, we had available orphan drug tax credits for federal purposes only of approximately $132.9 million. If not utilized, the orphan drug credits begin to expire in 2035.

As provided by Section 382 of the Internal Revenue Code of 1986, or Section 382, and similar state provisions, utilization of NOLs and tax credit carryforwards may be subject to substantial annual limitations due to ownership change limitations that have previously occurred or that could occur in the future. Ownership changes may limit the amount of NOLs and tax credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, results from transactions that increase the ownership of five percent stockholders in the stock of a corporation by more than 50 percent in the aggregate over a three year period. We completed a review of our changes in ownership through December 31, 2023 and determined that transactions have resulted in no ownership changes during the year ended December 31, 2023, as defined by Section 382. The impact of the historical ownership changes has been reflected in our deferred tax assets in the table above.

As required by ASC 740, we have evaluated the positive and negative evidence bearing upon the realizability of our deferred tax assets. Based on the weight of available evidence, both positive and negative, we recorded a valuation allowance of $379.7 million and $296.0 million as of December 31, 2023 and December 31, 2022, respectively, because we have determined that it is more likely than not that these assets will not be fully realized. The valuation allowance increased by $83.7 million for the year ended December 31, 2023 and by $59.5 million for the year ended December 31, 2022 primarily due to the Section 174 R&D expense capitalization.

The following table presents our change in valuation allowance for the years ended December 31, 2023 and, 2022:


(In thousands)	2023		2022
Valuation allowance at the beginning of the year	$	295,993	$	236,478
Increase (decrease) for the current period	83,667		59,515
Valuation allowance at the end of the year	$	379,660	$	295,993

As of December 31, 2023, the unremitted earnings of our foreign subsidiaries are not material. We have not provided for U.S. income taxes or foreign withholding taxes on these earnings as it is our current intention to permanently reinvest these earnings outside the U.S. The tax liability on these earnings is also not material. Events that could trigger a tax liability include, but are not limited to, distributions, reorganizations or restructurings and/or tax law changes.

We apply the accounting guidance in ASC 740 related to accounting for uncertainty in income taxes. Our reserves related to taxes are based on a determination of whether, and how much of, a tax benefit taken by us in our tax filings or positions is more likely than not to be realized following resolution of any potential contingencies present related to the tax benefit.

The following table presents our unrecognized tax benefits activity for the years ended December 31, 2023 and 2022:


(In thousands)	2023		2022
Unrecognized tax benefits at the beginning of the year	$	26,190	$	24,220
Gross increases - current period tax positions	2,388		1,970
Unrecognized tax benefits at the end of the year	$	28,578	$	26,190

We will recognize interest and penalties related to uncertain tax positions above the line as an expense to continuing operations. As of December 31, 2023 and 2022, we had no accrued interest or penalties related to uncertain tax positions and no such amounts have been recognized. If all of the Company’s unrecognized tax benefits as of December 31, 2023 were to become recognizable in the future, we would record $28.6 million of unrecognized tax benefits. The uncertain tax position does not impact our effective income tax rate due to the full valuation allowance.

We are subject to taxation in the United States, Switzerland, Netherlands, Germany, Italy and France. The statute of limitations for assessment by the IRS and state tax authorities is open for tax years ending December 31, 2023, 2022, 2021, and 2020, although carryforward attributes that were generated for tax years prior to 2020 may still be adjusted upon examination by the IRS or state tax authorities if they either have been, or will be, used in a future period. The statute of limitations for assessment in Switzerland remains open for tax years ending December 31, 2023, 2022, 2021, 2020 and 2019. The Company’s subsidiaries in the Netherlands and Germany were incorporated in 2019 and have statute of limitations for 5 and 4 years, respectively, for assessment. The tax years that remain open in these jurisdictions are for the tax years ending December 31, 2023, 2022, 2021, 2020 and 2019. The Company’s subsidiaries in Italy and France were incorporated in 2020 and have statute of limitations for 5 and 3 years, respectively, for assessment. The tax years that remain open in these jurisdictions are for the tax years ending December 31, 2023, 2022, 2021 and 2020. There are currently no federal, state or foreign audits in progress.

As of December 31, 2023 and 2022, we had an income tax receivable of $1.1 million and $0.3 million, respectively, recorded within prepaid expenses and other current assets.

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Accrued Expenses

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses consisted of the following at December 31:


(In thousands)	2023		2022
Accrued compensation	$	23,232	$	18,105
Accrued research and development costs	15,463		8,425
Accrued professional fees	3,115		2,435
Accrued other	1,357		1,385
Total accrued expenses	$	43,167	$	30,350

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Auditor Information [Abstract]
Auditor Firm ID	238
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Boston, Massachusetts

Income Taxes - Unrecognized Tax Benefits Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at the beginning of the year	$ 26,190	$ 24,220
Gross increases - current period tax positions	2,388	1,970
Unrecognized tax benefits at the end of the year	$ 28,578	$ 26,190

Leases - Schedule of Lease Expense and Other Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease costs	$ 15,227	$ 15,227	$ 15,229
Cash paid for amounts included in the measurement of operating lease liabilities	$ 18,170	$ 17,035	$ 14,411

Product Revenue - Schedule of Revenue-Related Reserves (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Reduction of accounts receivable	$ 151	$ 60
Component of accrued expenses	1,321	711
Total revenue-related reserves	$ 1,472	$ 771	$ 0

Discontinued Operations - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of contingent payments	$ 0	$ 127,853,000	$ 0
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group. including discontinued operation, assets	0	0
Disposal group. including discontinued operation, liabilities	0	$ 0
Gain on sale of contingent payments	$ 127,900,000

Marketable Securities - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 718,599	$ 970,269
Unrealized Gains	1,285	99
Unrealized Losses	(1,726)	(12,634)
Fair Value	718,158	957,734
Current:
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	689,381	652,339
Unrealized Gains	1,068	12
Unrealized Losses	(1,726)	(8,491)
Fair Value	688,723	643,860
Current: \| U.S. Treasuries
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	30,876	68,175
Unrealized Gains	0	3
Unrealized Losses	(56)	(811)
Fair Value	30,820	67,367
Current: \| Government securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	247,460	220,901
Unrealized Gains	194	8
Unrealized Losses	(695)	(5,289)
Fair Value	246,959	215,620
Current: \| Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	411,045	363,263
Unrealized Gains	874	1
Unrealized Losses	(975)	(2,391)
Fair Value	410,944	360,873
Non-current:
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,218	317,930
Unrealized Gains	217	87
Unrealized Losses	0	(4,143)
Fair Value	29,435	313,874
Non-current: \| U.S. Treasuries
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,802	17,418
Unrealized Gains	30	4
Unrealized Losses	0	(193)
Fair Value	4,832	17,229
Non-current: \| Government securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	9,986	117,475
Unrealized Gains	75	7
Unrealized Losses	0	(1,659)
Fair Value	10,061	115,823
Non-current: \| Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	14,430	183,037
Unrealized Gains	112	76
Unrealized Losses	0	(2,291)
Fair Value	$ 14,542	$ 180,822

Marketable Securities

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Marketable securities at December 31, 2023 consisted of the following:


(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:

U.S. Treasuries	$	30,876	$	—	$	(56)	$	30,820
Government securities	247,460		194		(695)		246,959
Corporate debt securities	411,045		874		(975)		410,944
Total Current	689,381		1,068		(1,726)		688,723

Non-current:
U.S. Treasuries	4,802		30		—		4,832
Government securities	9,986		75		—		10,061
Corporate debt securities	14,430		112		—		14,542
Total Non-current	29,218		217		—		29,435
Total marketable securities	$	718,599	$	1,285	$	(1,726)	$	718,158

Marketable securities at December 31, 2022 consisted of the following:


(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:

U.S. Treasuries	$	68,175	$	3	$	(811)	$	67,367
Government securities	220,901		8		(5,289)		215,620
Corporate debt securities	363,263		1		(2,391)		360,873
Total Current	652,339		12		(8,491)		643,860

Non-current:
U.S. Treasuries	17,418		4		(193)		17,229
Government securities	117,475		7		(1,659)		115,823
Corporate debt securities	183,037		76		(2,291)		180,822
Total Non-current	317,930		87		(4,143)		313,874
Total marketable securities	$	970,269	$	99	$	(12,634)	$	957,734

There were no material realized gains or losses on marketable securities for the years ended December 31, 2023 and 2022.

At December 31, 2023 and 2022, we held 151 and 259 debt securities, respectively, that were in an unrealized loss position for less than one year. We did not record an allowance for credit losses as of December 31, 2023 and 2022 related to these securities. The aggregate fair value of debt securities in an unrealized loss position at December 31, 2023 and 2022 was $513.5 million and $868.2 million, respectively. There were no individual securities that were in a significant unrealized loss position as of December 31, 2023 and 2022. We regularly review the securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. We do not consider these marketable securities to be impaired as of December 31, 2023 and 2022.

Nature of Business	12 Months Ended
Nature of Business	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business References to Agios Throughout this Annual Report on Form 10-K, “the Company,” “Agios,” “we,” “us,” and “our,” and similar expressions, except where the context requires otherwise, refer to Agios Pharmaceuticals, Inc. and its consolidated subsidiaries, and “our board of directors” refers to the board of directors of Agios Pharmaceuticals, Inc. Overview We are a biopharmaceutical company committed to transforming patients’ lives through leadership in the field of cellular metabolism, with the goal of creating differentiated medicines for rare diseases, with a focus on classical hematology. With a history of focused study on cellular metabolism, we have a deep and mature understanding of this biology, which is involved in the healthy functioning of nearly every system in the body. Building on this expertise, these learnings can be rapidly applied to our clinical trials with the goal of developing medicines that can have a significant impact for patients. We accelerate the impact of our portfolio by cultivating connections with patient communities, healthcare professionals, partners and colleagues to discover, develop and deliver potential therapies for rare diseases. We are located in Cambridge, Massachusetts. The lead product candidate in our portfolio, PYRUKYND® (mitapivat), is an activator of both wild-type and mutant pyruvate kinase, or PK, enzymes for the potential treatment of hemolytic anemias. In February 2022, the U.S. Food and Drug Administration, or FDA, approved PYRUKYND® for the treatment of hemolytic anemia in adults with PK deficiency in the United States. In November 2022, we received marketing authorization from the European Commission for PYRUKYND® for the treatment of PK deficiency in adult patients in the European Union, or EU. In December 2022, we received marketing authorization in Great Britain for PYRUKYND® for the treatment of PK deficiency in adult patients under the European Commission Decision Reliance Procedure. In addition, we are currently evaluating PYRUKYND® in clinical trials for the treatment of thalassemia, sickle cell disease, or SCD, and in pediatric patients with PK deficiency. We are also developing (i) AG-946, a novel PK activator, for the potential treatment of lower-risk myelodysplastic syndrome, or LR MDS, and hemolytic anemias, and (ii) AG-181, our phenylalanine hydroxylase, or PAH, stabilizer for the potential treatment of phenylketonuria, or PKU. In addition to the aforementioned development programs, in July 2023 we entered into a license agreement with Alnylam Pharmaceuticals, Inc., or Alnylam for the development and commercialization of products containing or comprised of an siRNA preclinical development candidate discovered by Alnylam and targeting the transmembrane serine protease 6, or TMPRSS6, gene and we intend to pursue development of a licensed product for the potential disease-modifying treatment of patients with polycythemia vera, or PV, a rare blood disorder. We are subject to risks common to companies in our industry including, but not limited to, uncertainties relating to conducting preclinical and clinical research and development, the manufacture and supply of products for clinical and commercial use, obtaining and maintaining regulatory approvals and pricing and reimbursement for our products, market acceptance, managing global growth and operating expenses, availability of additional capital, competition, obtaining and enforcing patents, stock price volatility, dependence on collaborative relationships and third-party service providers, dependence on key personnel, potential litigation, potential product liability claims and potential government investigations. Alnylam License Agreement On July 28, 2023, we entered into a license agreement with Alnylam under which we acquired the rights to develop and commercialize Alnylam’s novel preclinical siRNA targeting the TMPRSS6 gene, as a potential disease-modifying treatment for patients with PV. Because the acquired assets do not meet the definition of a business in accordance with ASC 805, Business Combinations, we will account for the agreement as an asset acquisition. In accordance with the license agreement, in the twelve months ended December 31, 2023, we made an up-front payment to Alnylam and recognized in-process research and development of $17.5 million which was recorded in research and development expense within our Consolidated Statements of Operations and classified as investing activities within our Consolidated Statements of Cash Flows. We will also pay Alnylam for certain expenses associated with the development of TMPRSS6 and these will be recorded in our Consolidated Statements of Operations as incurred. Additionally, we are responsible to pay up to $130.0 million in potential development and regulatory milestones, in addition to sales milestones as well as tiered royalties on annual net sales, if any, of licensed products, which may be subject to specified reductions and offsets. Sale of Oncology Business to Servier and Sale of Contingent Payments On March 31, 2021, we completed the sale of our oncology business to Servier Pharmaceuticals, LLC, or Servier, which represented a discontinued operation. The transaction included the sale of our oncology business, including TIBSOVO®, our clinical-stage product candidates vorasidenib, AG-270 and AG-636, and our oncology research programs for a payment of approximately $1.8 billion in cash at the closing, subject to certain adjustments, and a payment of $200.0 million in cash, if, prior to January 1, 2027, vorasidenib is granted new drug application, or NDA, approval from the FDA with an approved label that permits vorasidenib’s use as a single agent for the adjuvant treatment of patients with Grade 2 glioma that have an isocitrate dehydrogenase 1 or 2 mutation (and, to the extent required by such approval, the vorasidenib companion diagnostic test is granted an FDA premarket approval), as well as a royalty of 5% of U.S. net sales of TIBSOVO® from the close of the transaction through loss of exclusivity, and a royalty of 15% of U.S. net sales of vorasidenib from the first commercial sale of vorasidenib through loss of exclusivity. Servier also acquired our co-commercialization rights for Bristol Myers Squibb’s IDHIFA® and the right to receive a $25.0 million potential milestone payment under our prior collaboration agreement with Celgene Corporation, or Celgene, and following the sale Servier will conduct certain clinical development activities within the IDHIFA® development program. In October 2022, we sold our rights to future contingent payments associated with the royalty of 5% of U.S. net sales of TIBSOVO® from the close of the transaction through the loss of exclusivity to entities affiliated with Sagard Healthcare Partners, or Sagard, and recognized income of $127.9 million within the gain on sale of contingent payments line item in our Consolidated Statements of Operations for the year ended December 31, 2022. We retain our rights to the potential milestone payment and royalties from Servier if a new drug application for vorasidenib is approved by the FDA. We recorded income from royalties of $9.9 million and $6.6 million on U.S. net sales of TIBSOVO® by Servier in the royalty income from gain on sale of oncology business line item within the consolidated statements of operations for the years ended December 31, 2022 and December 31, 2021, respectively. Reclassifications Certain amounts in prior periods have been reclassified to reflect the impact of the discontinued operations treatment of the oncology business in order to conform to the current period presentation. Liquidity As of December 31, 2023, we had cash, cash equivalents and marketable securities of $806.4 million. Although we have incurred recurring losses and expect to continue to incur losses for the foreseeable future, we expect our cash, cash equivalents and marketable securities to be sufficient to fund current operations for at least the next twelve months from the issuance of the financial statements. If we are unable to raise additional funds through equity or debt financings, we may be required to delay, limit, reduce or terminate product development or future commercialization efforts or grant rights to develop and market products or product candidates that we would otherwise prefer to develop and market ourselves. On April 30, 2020, we entered into an at-the-market sales agreement, or the 2020 sales agreement, with Cowen & Company LLC, or Cowen, pursuant to which we may offer and sell shares of our common stock having an aggregate offering price of up to $250.0 million through Cowen pursuant to a universal shelf registration statement on Form S-3 filed with the SEC on April 30, 2020. As of December 31, 2022, $250.0 million in common stock remained available for future issuance under the 2020 sales agreement. On February 15, 2023, we delivered written notice to Cowen that we were terminating the 2020 sales agreement, effective on February 22, 2023. As of the termination of the 2020 sales agreement, we had not sold any shares of our common stock under the 2020 sales agreement.

Discontinued Operations - Summary of Gain on Sale of Discontinued Operations (Details) - USD ($) $ in Thousands		12 Months Ended
	Mar. 31, 2021	Dec. 31, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operation, gain (loss) on disposal, statement of income or comprehensive income [extensible enumeration]		Less: Net income from discontinued operations
Agios Oncology Business \| Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds	$ 1,800,000	$ 1,802,936
Less: transaction and insurance costs		(53,573)
Plus: net liabilities distributed, including working capital adjustment		239,770
Gain on sale, pre-tax		1,989,133
Income tax expense		(12,799)
Gain on sale, net of tax		$ 1,976,334

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2023
Equity [Abstract]
Common Stock	Common Stock We are authorized to issue 125,000,000 shares of our common stock. Holders of common stock are entitled to one vote per share. Additionally, holders of common stock are entitled to receive dividends, if and when declared by our board of directors, and to share ratably in our assets legally available for distribution to our shareholders in the event of liquidation.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Fair Value Measurements - Summary of Cash Equivalents and Marketable Securities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	$ 718,158	$ 957,734
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	30,123
Total marketable securities	718,158
Total cash equivalents and marketable securities	748,281
Fair Value, Measurements, Recurring \| U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	35,652
Fair Value, Measurements, Recurring \| Government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	257,020
Fair Value, Measurements, Recurring \| Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	425,486
Fair Value, Measurements, Recurring \| Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	30,123
Fair Value, Measurements, Recurring \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	30,123
Total marketable securities	0
Total cash equivalents and marketable securities	30,123
Fair Value, Measurements, Recurring \| Level 1 \| U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 1 \| Government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 1 \| Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 1 \| Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	30,123
Fair Value, Measurements, Recurring \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0
Total marketable securities	718,158
Total cash equivalents and marketable securities	718,158
Fair Value, Measurements, Recurring \| Level 2 \| U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	35,652
Fair Value, Measurements, Recurring \| Level 2 \| Government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	257,020
Fair Value, Measurements, Recurring \| Level 2 \| Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	425,486
Fair Value, Measurements, Recurring \| Level 2 \| Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0
Fair Value, Measurements, Recurring \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0
Total marketable securities	0
Total cash equivalents and marketable securities	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 3 \| Government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 3 \| Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Fair Value, Measurements, Recurring \| Level 3 \| Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	$ 0

Marketable Securities - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Investments, Debt and Equity Securities [Abstract]
Realized gain (loss) on marketable securities	$ 0	$ 0
Number of debt securities in an unrealized loss position for less than one year \| security	151	259
Allowance for credit losses	$ 0	$ 0
Aggregate fair value of debt securities in an unrealized loss position	$ 513,500,000	$ 868,200,000
Number of unrealized loss position \| security	0	0

Property and Equipment, net - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 67,611	$ 73,057
Less: accumulated depreciation	(52,229)	(50,070)
Total property and equipment, net	15,382	22,987
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	17,433	23,182
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment	6,566	6,179
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	37,277	37,277
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	3,459	3,514
Office equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	2,268	2,248
Construction in progress
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 608	$ 657

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Treasury
Common stock, beginning balance (in shares) at Dec. 31, 2020		69,293,920
Beginning balance at Dec. 31, 2020	$ 399,500	$ 69	$ 2,242,801	$ 105	$ (1,843,475)	$ 0
Treasury stock, beginning balance (in shares) at Dec. 31, 2020						0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized gain (loss) on available-for-sale securities	(1,303)			(1,303)
Net (loss) income	1,604,715				1,604,715
Stock-based compensation expense	53,508		53,508
Common stock issued under stock incentive plan and ESPP (in shares)		1,256,711
Common stock issued under stock incentive plan and ESPP	37,296	$ 2	37,294
Repurchase of common stock (in shares)						(16,216,411)
Repurchase of common stock	(802,486)					$ (802,486)
Disposition of oncology business	745		745
Common stock, ending balance (in shares) at Dec. 31, 2021		70,550,631
Ending balance at Dec. 31, 2021	1,291,975	$ 71	2,334,348	(1,198)	(238,760)	$ (802,486)
Treasury stock, ending balance (in shares) at Dec. 31, 2021						(16,216,411)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized gain (loss) on available-for-sale securities	(11,337)			(11,337)
Net (loss) income	(231,801)				(231,801)
Stock-based compensation expense	49,296		49,296
Common stock issued under stock incentive plan and ESPP (in shares)		705,487
Common stock issued under stock incentive plan and ESPP	$ 2,681		2,681
Common stock, ending balance (in shares) at Dec. 31, 2022	55,039,707	71,256,118
Ending balance at Dec. 31, 2022	$ 1,100,814	$ 71	2,386,325	(12,535)	(470,561)	$ (802,486)
Treasury stock, ending balance (in shares) at Dec. 31, 2022	(16,216,411)					(16,216,411)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized gain (loss) on available-for-sale securities	$ 12,094			12,094
Net (loss) income	(352,088)				(352,088)
Stock-based compensation expense	$ 44,766		44,766
Common stock issued under stock incentive plan and ESPP (in shares)	235,401	905,371
Common stock issued under stock incentive plan and ESPP	$ 5,433	$ 1	5,432
Common stock, ending balance (in shares) at Dec. 31, 2023	55,945,078	72,161,489
Ending balance at Dec. 31, 2023	$ 811,019	$ 72	$ 2,436,523	$ (441)	$ (822,649)	$ (802,486)
Treasury stock, ending balance (in shares) at Dec. 31, 2023	(16,216,411)					(16,216,411)

Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Marketable Securities

Marketable securities at December 31, 2023 consisted of the following:


(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:

U.S. Treasuries	$	30,876	$	—	$	(56)	$	30,820
Government securities	247,460		194		(695)		246,959
Corporate debt securities	411,045		874		(975)		410,944
Total Current	689,381		1,068		(1,726)		688,723

Non-current:
U.S. Treasuries	4,802		30		—		4,832
Government securities	9,986		75		—		10,061
Corporate debt securities	14,430		112		—		14,542
Total Non-current	29,218		217		—		29,435
Total marketable securities	$	718,599	$	1,285	$	(1,726)	$	718,158

Marketable securities at December 31, 2022 consisted of the following:


(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:

U.S. Treasuries	$	68,175	$	3	$	(811)	$	67,367
Government securities	220,901		8		(5,289)		215,620
Corporate debt securities	363,263		1		(2,391)		360,873
Total Current	652,339		12		(8,491)		643,860

Non-current:
U.S. Treasuries	17,418		4		(193)		17,229
Government securities	117,475		7		(1,659)		115,823
Corporate debt securities	183,037		76		(2,291)		180,822
Total Non-current	317,930		87		(4,143)		313,874
Total marketable securities	$	970,269	$	99	$	(12,634)	$	957,734

Share-Based Payments - Schedule of Unvested RSUs, Performance-Based Stock and Market-Based Stock Unit Activity (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Restricted stock units
Number of Stock Units
Unvested shares beginning of period (in shares) \| shares	1,117,921
Granted (in shares) \| shares	914,943
Vested (in shares) \| shares	(464,881)
Forfeited (in shares) \| shares	(221,282)
Unvested shares end of period (in shares) \| shares	1,346,701
Weighted-Average Grant Date Fair Value
Unvested shares beginning of period (in usd per share) \| $ / shares	$ 38.30
Granted (in usd per share) \| $ / shares	25.93
Vested (in usd per share) \| $ / shares	41.36
Forfeited (in usd per share) \| $ / shares	33.25
Unvested shares end of period (in usd per share) \| $ / shares	$ 29.67
Performance-based stock units
Number of Stock Units
Unvested shares beginning of period (in shares) \| shares	430,243
Granted (in shares) \| shares	125,897
Vested (in shares) \| shares	(92,257)
Forfeited (in shares) \| shares	(101,750)
Unvested shares end of period (in shares) \| shares	362,133
Weighted-Average Grant Date Fair Value
Unvested shares beginning of period (in usd per share) \| $ / shares	$ 35.87
Granted (in usd per share) \| $ / shares	25.23
Vested (in usd per share) \| $ / shares	30.18
Forfeited (in usd per share) \| $ / shares	46.39
Unvested shares end of period (in usd per share) \| $ / shares	$ 30.66
Market-based stock units
Number of Stock Units
Unvested shares beginning of period (in shares) \| shares	42,695
Granted (in shares) \| shares	0
Unvested shares end of period (in shares) \| shares	42,695
Weighted-Average Grant Date Fair Value
Unvested shares beginning of period (in usd per share) \| $ / shares	$ 41.50
Granted (in usd per share) \| $ / shares	0
Unvested shares end of period (in usd per share) \| $ / shares	$ 41.50

Product Revenue - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Contract assets	$ 2,810	$ 2,206	$ 0

Property and Equipment, net

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property and Equipment, net

Property and equipment, net consisted of the following at December 31:


(In thousands)	2023		2022
Laboratory equipment	$	17,433	$	23,182
Computer equipment and software	6,566		6,179
Leasehold improvements	37,277		37,277
Furniture and fixtures	3,459		3,514
Office equipment	2,268		2,248
Construction in progress	608		657
Total property and equipment	67,611		73,057
Less: accumulated depreciation	(52,229)		(50,070)
Total property and equipment, net	$	15,382	$	22,987

Depreciation expense for the years ended December 31, 2023, 2022 and 2021 was $6.6 million, $8.4 million and $8.8 million, respectively.

Product Revenue - Schedule of Changes in Contract Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Contract Assets and Liabilities [Roll Forward]
Contract assets, beginning balance	$ 2,206	$ 0
Additions	31,855	13,283
Deductions	(31,251)	(11,077)
Contract assets, ending balance	$ 2,810	$ 2,206

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of Domestic and Foreign Components of Loss Before Income Taxes

The domestic and foreign components of loss from continuing operations before income taxes are as follows:


(In thousands)	2023		2022		2021
Domestic	$	(352,085)	$	(231,767)	$	(356,665)
Foreign	(3)		(34)		155
Total	$	(352,088)	$	(231,801)	$	(356,510)

Reconciliation of Expected Income Tax Benefit (Expense) Computed Using Federal Statutory Income Tax Rate


	2023		2022		2021
Income tax benefit computed at federal statutory tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	1.9	%	2.9	%	2.6	%
Change in valuation allowance	(23.8)	%	(25.7)	%	(24.5)	%
General business credits and other credits	4.2	%	5.2	%	5.3	%
Permanent differences and other adjustments	(2.8)	%	(2.3)	%	(3.9)	%
Stock based compensation	(0.5)	%	(1.1)	%	(0.5)	%


Total	—	%	—	%	—	%

Company's Deferred Tax Assets and Liabilities

Significant components of our deferred tax assets and liabilities for the years ended December 31, 2023 and 2022 are as follows:


(In thousands)	2023		2022
Deferred tax assets:
Net operating loss carryforwards	$	64,066	$	32,907

Tax credit carryforwards	180,635		163,780
Purchased intangible assets	14,155		11,583
Stock-based compensation	20,954		26,236
Operating lease liability	16,780		21,042
Non-deductible accruals and reserves, including inventory	5,134		3,992
Section 174 R&D expense	93,333		56,565

Total deferred tax assets	395,057		316,105
Depreciation and amortization	(1,986)		(3,767)
Operating lease right of use asset	(13,411)		(16,345)
Less: valuation allowance	(379,660)		(295,993)
Net deferred taxes	$	—	$	—

Changes in Valuation Allowance

The following table presents our change in valuation allowance for the years ended December 31, 2023 and, 2022:


(In thousands)	2023		2022
Valuation allowance at the beginning of the year	$	295,993	$	236,478
Increase (decrease) for the current period	83,667		59,515
Valuation allowance at the end of the year	$	379,660	$	295,993

Schedule of Unrecognized Tax Benefits Rollforward

The following table presents our unrecognized tax benefits activity for the years ended December 31, 2023 and 2022:


(In thousands)	2023		2022
Unrecognized tax benefits at the beginning of the year	$	26,190	$	24,220
Gross increases - current period tax positions	2,388		1,970
Unrecognized tax benefits at the end of the year	$	28,578	$	26,190

Share-Based Payments - Schedule of Stock-Based Compensation Expense by Award Type Included within the Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 44,766	$ 49,296	$ 53,508
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	17,163	23,731	30,985
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	19,367	21,670	21,510
Performance-based stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7,368	2,919	0
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 868	$ 976	$ 1,013

- Definition

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

+ References

+ Details

Income Taxes - Reconciliation of Expected Income Tax Benefit (Expense) Computed Using Federal Statutory Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax benefit computed at federal statutory tax rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	1.90%	2.90%	2.60%
Change in valuation allowance	(23.80%)	(25.70%)	(24.50%)
General business credits and other credits	4.20%	5.20%	5.30%
Permanent differences and other adjustments	(2.80%)	(2.30%)	(3.90%)
Stock based compensation	(0.50%)	(1.10%)	(0.50%)
Total	0.00%	0.00%	0.00%

Share-Based Payments (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Company's Stock Option Activity

The following table summarizes the stock option activity of all stock incentive plans for the year ended December 31, 2023:


	Number of Stock Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2022	5,772,564	$	48.81	6.50	$	5,362
Granted	886,795	25.84
Exercised	(235,401)	12.83
Forfeited/Expired	(1,160,277)	56.10
Outstanding at December 31, 2023	5,263,681	$	44.94	6.36	$	423
Exercisable at December 31, 2023	3,344,010	$	53.55	5.02	$	398
Vested and expected to vest at December 31, 2023	5,263,681	$	44.94	6.36	$	423

Schedule of RSU Activity

The following table presents RSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	1,117,921	$	38.30
Granted	914,943	25.93
Vested	(464,881)	41.36
Forfeited	(221,282)	33.25
Unvested shares at December 31, 2023	1,346,701	$	29.67

Schedule of PSU Activity

The following table presents PSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	430,243	$	35.87
Granted	125,897	25.23
Vested	(92,257)	30.18
Forfeited	(101,750)	46.39

Unvested shares at December 31, 2023	362,133	$	30.66

Schedule of Market-based Stock Unit or MSU Activity

The following table presents MSU activity for the year ended December 31, 2023:


	Number of Stock Units	Weighted-Average Grant Date Fair Value
Unvested shares at December 31, 2022	42,695	$	41.50
Granted	—	—
Unvested shares at December 31, 2023	42,695	$	41.50

Schedule of Stock-Based Compensation Expense by Award Type Included within the Condensed Consolidated Statements of Operations

Stock-based compensation expense by award type included within the consolidated statements of operations is as follows:


(In thousands)	2023		2022		2021
Stock options	$	17,163	$	23,731	$	30,985
Restricted stock units	19,367		21,670		21,510
Performance-based stock units	7,368		2,919		—
Employee Stock Purchase Plan	868		976		1,013

Total stock-based compensation expense	$	44,766	$	49,296	$	53,508

Schedule of Expenses Related to Stock Options and Stock-based Awards

Expenses related to equity-based awards were allocated as follows in the consolidated statements of operations:


(In thousands)	2023		2022		2021
Research and development expense	$	17,064	$	20,988	$	24,527
Selling, general and administrative expense	27,702		28,308		28,981
Total stock-based compensation expense	$	44,766	$	49,296	$	53,508

Schedule of Grant Date Fair Value Option Award Weighted Average Assumptions Used

The following table summarizes the weighted average assumptions used in calculating the grant date fair value of the awards:


	2023		2022		2021
Risk-free interest rate	4.05	%	2.55	%	0.72	%
Expected dividend yield	—		—		—
Expected term (in years)	5.99		6.03		6.05
Expected volatility	54.26	%	55.30	%	61.72	%

Income Taxes - Changes in Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Deferred Tax Assets, Valuation Allowance [Roll Forward]
Valuation allowance at the beginning of the year	$ 295,993	$ 236,478
Increase (decrease) for the current period	83,667	59,515
Valuation allowance at the end of the year	$ 379,660	$ 295,993

Share Repurchase Program (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended			33 Months Ended
	Apr. 05, 2021	Mar. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023	Apr. 02, 2021	Mar. 25, 2021
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock					$ 802,486
Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount								$ 1,200,000
Shares repurchased (in shares)			0	0		16,200,000
Repurchase of common stock						$ 802,500
Shares repurchased (in usd per share)						$ 49.49
BMS Repurchase
Equity, Class of Treasury Stock [Line Items]
Shares repurchased (in shares)		7,100,000
Repurchase of common stock	$ 344,500
Shares repurchased (in usd per share)	$ 48.38
Rule 10b5-1 Repurchase
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount							$ 600,000
Shares repurchased (in shares)			9,100,000
Repurchase of common stock			$ 458,000
Shares repurchased (in usd per share)			$ 50.35

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued compensation	$ 23,232	$ 18,105
Accrued research and development costs	15,463	8,425
Accrued professional fees	3,115	2,435
Accrued other	1,357	1,385
Total accrued expenses	$ 43,167	$ 30,350

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consisted of the following at December 31:


(In thousands)	2023		2022
Accrued compensation	$	23,232	$	18,105
Accrued research and development costs	15,463		8,425
Accrued professional fees	3,115		2,435
Accrued other	1,357		1,385
Total accrued expenses	$	43,167	$	30,350

Fair Value Measurements - Additional Information (Details)	Dec. 31, 2023 USD ($)
Fair Value, Measurements, Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets (liabilities)	$ 0