0001628280-23-035793 | 10-Q | XBRL Viewer

Stock-based compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of stock-based compensation expense

Stock-based compensation expense for the three and nine months ended September 30, 2023 and 2022 was classified in the Company’s condensed consolidated statement of operations and comprehensive loss as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Stock-based compensation expense:
Research and development	$	3,906	$	2,636	$	9,133	$	10,024
General and administrative	4,294		3,375		11,743		13,073
Total stock-based compensation expense	$	8,200	$	6,011	$	20,876	$	23,097

Summary of RSU activity

The following table summarizes the Company’s RSU activity for the nine months ended September 30, 2023:


	Shares	Weighted-Average Grant Date Fair Value
Outstanding as of December 31, 2022	—	$	—
Issued	824,600	5.37
Vested	—	—
Forfeited	(68,640)	$	5.67
Outstanding as of September 30, 2023	755,960	$	5.35

As of September 30, 2023, the unrecognized compensation cost related to outstanding RSUs was $3.4 million, which is expected to be recognized over a weighted-average period of 3.4 years.

Property and equipment

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment [Abstract]

Property and equipment

Property and equipment consisted of the following (in thousands):


	September 30, 2023		December 31, 2022
Property and equipment:
Laboratory equipment	$	8,303	$	8,757
Leasehold improvements	4,766		4,682
Furniture and fixtures	1,181		1,181
Office equipment	621		529
Construction in progress	223		183
Computer equipment	98		191
Total property and equipment	15,192		15,523
Less: accumulated depreciation	(7,902)		(8,123)
Total property and equipment, net	$	7,290	$	7,400

Depreciation expense related to property and equipment is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Depreciation expense	$	447	$	415	$	1,450	$	1,155

Cover - shares	9 Months Ended
Cover - shares	Sep. 30, 2023	Oct. 25, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity File Number	001-39567
Entity Registrant Name	C4 Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-5617627
Entity Address, Address Line One	490 Arsenal Way
Entity Address, Address Line Two	Suite 120
Entity Address, City or Town	Watertown
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02472
City Area Code	617
Local Phone Number	231-0700
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	CCCC
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		49,281,046
Entity Central Index Key	0001662579
Amendment Flag	false

Long-term debt – related party - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2020	Jun. 05, 2020
Long Term Debt And Warrant Liability [Line Items]
Loss on early extinguishment of debt	$ 621	$ 0	$ 621	$ 0
Credit Agreement with Perceptive Life Sciences Master Fund LTD \| Term Loan
Long Term Debt And Warrant Liability [Line Items]
Aggregate principal borrowing amount						$ 20,000
Credit Agreement with Perceptive Life Sciences Master Fund LTD \| Term Loan \| Tranche one
Long Term Debt And Warrant Liability [Line Items]
Aggregate principal borrowing amount						12,500
Amount withdrawn					$ 12,500
Credit Agreement with Perceptive Life Sciences Master Fund LTD \| Term Loan \| Tranche two
Long Term Debt And Warrant Liability [Line Items]
Aggregate principal borrowing amount						$ 7,500

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References + Details

Long-term debt – related party - Schedule of long-term debt (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Term Loan — related party, net of unamortized debt issuance costs and debt discount of $1,018 at December 31, 2022		$ 11,482
Long-term debt − related party, current and net of discount	$ 0	2,287
Long-term debt − related party, net of current and discount	$ 0	9,195
Unamortized debt issuance costs and debt discount		$ 1,018

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Accrued expenses and other current liabilities

9 Months Ended

Sep. 30, 2023

Payables and Accruals [Abstract]

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):


	September 30, 2023		December 31, 2022
Accrued expenses and other current liabilities:
Accrued research and development	$	7,399	$	9,824
Accrued compensation and benefits	5,974		6,831
Other	2,111		3,114
Total accrued expenses and other current liabilities	$	15,484	$	19,769

Stock-based compensation

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Stock-based compensation


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Stock-based compensation expense:
Research and development	$	3,906	$	2,636	$	9,133	$	10,024
General and administrative	4,294		3,375		11,743		13,073
Total stock-based compensation expense	$	8,200	$	6,011	$	20,876	$	23,097

Stock options

During the nine months ended September 30, 2023, the Company granted stock options for the purchase of 4,427,620 shares of common stock with a weighted average exercise price of $3.89 per share and a weighted average grant-date fair value of $2.86 per shares. As of September 30, 2023, the unrecognized compensation cost related to outstanding stock options was $42.9 million, which is expected to be recognized over a weighted-average period of 2.4 years.

Performance-based restricted stock units

During the three and nine months ended September 30, 2023, the Company did not grant any performance-based restricted stock units, or PSUs. 135,301 PSUs vested during the nine months ended September 30, 2023 upon their respective achievement of performance-based vesting criteria. Upon vesting, each PSU automatically converted into one share of the Company’s common stock. The Company indirectly repurchased 17,556 shares of its common stock through net-share settlement as consideration for employee tax withholding obligations arising upon vesting of the PSUs, which tax amounts were remitted to the applicable revenue authorities in cash. As of September 30, 2023, the unrecognized compensation cost related to outstanding PSUs with performance-based vesting criteria that are considered not probable of achievement was $6.4 million.

Time-based restricted stock units

During the three and nine months ended September 30, 2023, the Company issued restricted stock units, or RSUs, that were subject to time-based vesting conditions to its employees . These RSUs are valued on the grant date using the grant date market price of the underlying shares. Upon vesting, each RSU automatically converts into one share of the Company’s common stock.

The following table summarizes the Company’s RSU activity for the nine months ended September 30, 2023:


	Shares	Weighted-Average Grant Date Fair Value
Outstanding as of December 31, 2022	—	$	—
Issued	824,600	5.37
Vested	—	—
Forfeited	(68,640)	$	5.67
Outstanding as of September 30, 2023	755,960	$	5.35

As of September 30, 2023, the unrecognized compensation cost related to outstanding RSUs was $3.4 million, which is expected to be recognized over a weighted-average period of 3.4 years.

Marketable securities

9 Months Ended

Sep. 30, 2023

Marketable Securities [Abstract]

Marketable securities

Marketable securities as of September 30, 2023 consisted of the following (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable securities, current:
Corporate debt securities	$	105,508	$	7	$	(503)	$	105,012
U.S. government debt securities	40,898		—		(223)		40,675
U.S. Treasury securities	9,914		—		(3)		9,911
Marketable securities, non-current:
Corporate debt securities	22,112		—		(128)		21,984
U.S. government debt securities	7,927		—		(54)		7,873

Total marketable securities, current and non-current	$	186,359	$	7	$	(911)	$	185,455

Marketable securities as of December 31, 2022 consisted of the following (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable securities, current:
Corporate debt securities	$	183,270	$	2	$	(2,068)	$	181,204
U.S. government debt securities	40,986		—		(1,184)		39,802
U.S. Treasury securities	25,650		—		(257)		25,393
Marketable securities, non-current:
Corporate debt securities	53,592		2		(471)		53,123
U.S. government debt securities	8,000		—		(161)		7,839

Total marketable securities, current and non-current	$	311,498	$	4	$	(4,141)	$	307,361

Marketable securities classified as current have maturities of less than one year and are classified as available-for-sale. Marketable securities classified as non-current are those that: (i) have a maturity of greater than one year, and (ii) are not intended to be liquidated within the next twelve months, although these funds are available for use and, therefore, are

classified as available-for-sale. No available-for-sale debt securities held as of September 30, 2023 or December 31, 2022 had remaining maturities greater than five years.

Based on factors such as historical experience, market data, issuer-specific factors, and current economic conditions, the Company did not record an allowance for credit losses at September 30, 2023 and December 31, 2022, related to these securities.

Marketable securities (Tables)

9 Months Ended

Sep. 30, 2023

Marketable Securities [Abstract]

Summary of marketable securities

Marketable securities as of September 30, 2023 consisted of the following (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable securities, current:
Corporate debt securities	$	105,508	$	7	$	(503)	$	105,012
U.S. government debt securities	40,898		—		(223)		40,675
U.S. Treasury securities	9,914		—		(3)		9,911
Marketable securities, non-current:
Corporate debt securities	22,112		—		(128)		21,984
U.S. government debt securities	7,927		—		(54)		7,873

Total marketable securities, current and non-current	$	186,359	$	7	$	(911)	$	185,455

Marketable securities as of December 31, 2022 consisted of the following (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable securities, current:
Corporate debt securities	$	183,270	$	2	$	(2,068)	$	181,204
U.S. government debt securities	40,986		—		(1,184)		39,802
U.S. Treasury securities	25,650		—		(257)		25,393
Marketable securities, non-current:
Corporate debt securities	53,592		2		(471)		53,123
U.S. government debt securities	8,000		—		(161)		7,839

Total marketable securities, current and non-current	$	311,498	$	4	$	(4,141)	$	307,361

Collaboration and license agreements - Schedule of financial information related to collaboration and license agreements (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	$ 500	$ 1,473
Deferred revenue, current	8,424	16,618
Deferred revenue, net of current	19,623	16,895
Deferred revenue, total	28,047	33,513
Roche Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	500	417
Deferred revenue, current	2,464	4,649
Deferred revenue, net of current	11,845	16,895
Deferred revenue, total	14,309	21,544
Biogen Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	0	0
Deferred revenue, current	3,738	11,427
Deferred revenue, net of current	0	0
Deferred revenue, total	3,738	11,427
Calico Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	0	1,056
Deferred revenue, current	0	542
Deferred revenue, net of current	0	0
Deferred revenue, total	0	$ 542
Betta Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	0
Deferred revenue, current	2,222
Deferred revenue, net of current	7,778
Deferred revenue, total	$ 10,000

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2021		48,688,875
Beginning balance at Dec. 31, 2021	$ 389,606	$ 5	$ 658,091	$ (775)	$ (267,715)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		52,707
Issuance of common stock upon exercise of stock options	260		260
Issuances of common stock under 2020 ESPP (in shares)		8,028
Issuance of common stock under 2020 ESPP	220		220
Stock-based compensation	8,879		8,879
Change in unrealized loss, net on marketable securities	(2,875)			(2,875)
Net loss	(31,620)				(31,620)
Other (in shares)		1,880
Other	59		59
Ending balance (in shares) at Mar. 31, 2022		48,751,490
Ending balance at Mar. 31, 2022	364,529	$ 5	667,509	(3,650)	(299,335)
Beginning balance (in shares) at Dec. 31, 2021		48,688,875
Beginning balance at Dec. 31, 2021	389,606	$ 5	658,091	(775)	(267,715)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in unrealized loss, net on marketable securities	(4,634)
Net loss	(90,990)
Ending balance (in shares) at Sep. 30, 2022		48,951,283
Ending balance at Sep. 30, 2022	318,179	$ 5	682,288	(5,409)	(358,705)
Beginning balance (in shares) at Mar. 31, 2022		48,751,490
Beginning balance at Mar. 31, 2022	364,529	$ 5	667,509	(3,650)	(299,335)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		124,677
Issuance of common stock upon exercise of stock options	259		259
Stock-based compensation	8,109		8,109
Change in unrealized loss, net on marketable securities	(931)			(931)
Net loss	(27,412)				(27,412)
Other (in shares)		1,485
Other	39		39
Ending balance (in shares) at Jun. 30, 2022		48,877,652
Ending balance at Jun. 30, 2022	344,593	$ 5	675,916	(4,581)	(326,747)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		46,367
Issuance of common stock upon exercise of stock options	211		211
Issuances of common stock under 2020 ESPP (in shares)		23,374
Issuance of common stock under 2020 ESPP	150		150
Stock-based compensation	5,980		5,980
Change in unrealized loss, net on marketable securities	(828)			(828)
Net loss	(31,958)				(31,958)
Other (in shares)		3,890
Other	31		31
Ending balance (in shares) at Sep. 30, 2022		48,951,283
Ending balance at Sep. 30, 2022	318,179	$ 5	682,288	(5,409)	(358,705)
Beginning balance (in shares) at Dec. 31, 2022		48,966,216
Beginning balance at Dec. 31, 2022	289,234	$ 5	689,256	(4,137)	(395,890)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		11,759
Issuance of common stock upon exercise of stock options	56		56
Issuance of common stock upon vesting of restricted stock units, net of shares repurchased for tax withholding (in shares)		48,730
Issuance of common stock upon vesting of restricted stock units, net of shares repurchased for tax withholding	(94)		(94)
Issuances of common stock under 2020 ESPP (in shares)		20,748
Issuance of common stock under 2020 ESPP	104		104
Stock-based compensation	6,251		6,251
Change in unrealized loss, net on marketable securities	1,667			1,667
Net loss	(34,780)				(34,780)
Other (in shares)		5,056
Other	32		32
Ending balance (in shares) at Mar. 31, 2023		49,052,509
Ending balance at Mar. 31, 2023	262,470	$ 5	695,605	(2,470)	(430,670)
Beginning balance (in shares) at Dec. 31, 2022		48,966,216
Beginning balance at Dec. 31, 2022	289,234	$ 5	689,256	(4,137)	(395,890)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in unrealized loss, net on marketable securities	3,233
Net loss	(97,739)
Ending balance (in shares) at Sep. 30, 2023		49,259,870
Ending balance at Sep. 30, 2023	216,024	$ 5	710,552	(904)	(493,629)
Beginning balance (in shares) at Mar. 31, 2023		49,052,509
Beginning balance at Mar. 31, 2023	262,470	$ 5	695,605	(2,470)	(430,670)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		1,337
Issuance of common stock upon exercise of stock options	2		2
Stock-based compensation	6,425		6,425
Change in unrealized loss, net on marketable securities	696			696
Net loss	(35,922)				(35,922)
Other (in shares)		11,252
Other	36		36
Ending balance (in shares) at Jun. 30, 2023		49,065,098
Ending balance at Jun. 30, 2023	233,707	$ 5	702,068	(1,774)	(466,592)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon vesting of restricted stock units, net of shares repurchased for tax withholding (in shares)		69,015
Issuance of common stock upon vesting of restricted stock units, net of shares repurchased for tax withholding	(16)		(16)
Issuances of common stock under 2020 ESPP (in shares)		113,036
Issuance of common stock under 2020 ESPP	264		264
Stock-based compensation	8,200		8,200
Change in unrealized loss, net on marketable securities	870			870
Net loss	(27,037)				(27,037)
Other (in shares)		12,721
Other	36		36
Ending balance (in shares) at Sep. 30, 2023		49,259,870
Ending balance at Sep. 30, 2023	$ 216,024	$ 5	$ 710,552	$ (904)	$ (493,629)

Marketable securities - Summary of marketable securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Marketable securities, current:
Fair Value	$ 155,598	$ 246,399
Marketable securities, non-current:
Fair Value	29,857	60,962
Amortized Cost	186,359	311,498
Gross Unrealized Gains	7	4
Gross Unrealized Losses	(911)	(4,141)
Fair Value	185,455	307,361
Corporate debt securities
Marketable securities, current:
Amortized Cost	105,508	183,270
Gross Unrealized Gains	7	2
Gross Unrealized Losses	(503)	(2,068)
Fair Value	105,012	181,204
Marketable securities, non-current:
Amortized Cost	22,112	53,592
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(128)	(471)
Fair Value	21,984	53,123
U.S. government debt securities
Marketable securities, current:
Amortized Cost	40,898	40,986
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(223)	(1,184)
Fair Value	40,675	39,802
Marketable securities, non-current:
Amortized Cost	7,927	8,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(54)	(161)
Fair Value	7,873	7,839
U.S. Treasury securities
Marketable securities, current:
Amortized Cost	9,914	25,650
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3)	(257)
Fair Value	$ 9,911	$ 25,393

Collaboration and license agreements - Schedule of supplemental financial information related to collaboration and license agreements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenue recognized that was included in the contract liability at the beginning of the period	$ 11,028	$ 5,517	$ 16,923	$ 24,005
Revenue recognized from performance obligations fully or partially satisfied in previous periods	$ 43	$ 0	$ 43	$ 518

Income taxes (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
Income taxes (Details) - USD ($)	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income tax provision (benefit)	$ 1,003,000	$ 0	$ 1,003,000	$ 0	$ 0
Effective tax rate			(1.00%)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Summary of significant accounting policies	9 Months Ended
Summary of significant accounting policies	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of significant accounting policies	Summary of significant accounting policies Basis of presentation and consolidation The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or U.S. GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or the SEC, regarding interim financial reporting, and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. These condensed consolidated financial statements include the accounts of C4 Therapeutics, Inc. and its subsidiary, C4T Securities Corporation. All intercompany balances and transactions have been eliminated in consolidation. Unaudited interim financial information The accompanying condensed consolidated balance sheet as of September 30, 2023, the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022, the condensed consolidated statements of stockholders’ equity for the three and nine months ended September 30, 2023 and 2022, and the condensed consolidated statements of cash flows for the nine months ended September 30, 2023 and 2022, and the related interim disclosures are unaudited. These unaudited condensed consolidated financial statements include all adjustments necessary, consisting of only normal recurring adjustments, to fairly state the financial position and the results of the Company’s operations and cash flows for interim periods in accordance with U.S. GAAP. Interim period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of and for year ended December 31, 2022, and notes thereto, which are included in the Company’s Annual Report on Form 10-K that was filed with the SEC on February 23, 2023. Use of estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. This process may result in actual results differing materially from those estimated amounts used in the preparation of the condensed consolidated financial statements if these results differ from historical experience or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, amounts and timing of revenues recognized under the Company’s research and development collaboration arrangements, prepaid and accrued research and development expense, incremental borrowing rate used in the measurement of lease liabilities, and estimated volatility used in fair valuation of stock options. The Company assesses estimates on an ongoing basis; however, actual results could materially differ from those estimates. Significant accounting policies The Company’s significant accounting policies are disclosed in the audited condensed consolidated financial statements for the year ended December 31, 2022, which are included in the Company’s Annual Report on Form 10-K that was filed with the SEC on February 23, 2023. Since the date of those condensed consolidated financial statements, there have been no material changes to the Company’s significant accounting policies.

Loss per share

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Loss per share

For periods in which the Company reports a net loss attributable to common stockholders, potentially dilutive securities have been excluded from the computation of diluted net loss per share as their effects would be anti-dilutive. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. For purposes of the dilutive net loss per share calculation, stock options, and restricted stock units for which the performance or market vesting conditions have been met are considered to be common stock equivalents, while restricted stock units with performance or market vesting conditions that were not met as of September 30, 2023 are not considered to be common stock equivalents. The Company excluded the following potential common shares presented based on amounts outstanding at period end from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect:


	As of September 30,
	2023	2022
Anti-dilutive common stock equivalents:
Options to purchase common stock	9,868,099	6,952,795

Total anti-dilutive common stock equivalents	9,868,099	6,952,795

Basic and diluted loss per share is computed by dividing net loss by the weighted-average common shares outstanding for the three and nine months ended September 30, 2023 and 2022 (in thousands, except share and per share data):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Numerator:
Net loss	$	(27,037)	$	(31,958)	$	(97,739)	$	(90,990)
Denominator:
Weighted-average number of shares used in computed net loss per share − basic and diluted	49,212,126		48,921,928		49,103,351		48,827,503
Net loss per share − basic and diluted	$	(0.55)	$	(0.65)	$	(1.99)	$	(1.86)

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue from collaboration agreements	$ 11,072,000	$ 6,754,000	$ 17,495,000	$ 28,242,000
Operating expenses:
Research and development	28,347,000	29,663,000	87,315,000	87,189,000
General and administrative	10,533,000	9,579,000	31,784,000	32,294,000
Total operating expenses	38,880,000	39,242,000	119,099,000	119,483,000
Loss from operations	(27,808,000)	(32,488,000)	(101,604,000)	(91,241,000)
Other income (expense), net:
Interest expense and amortization of long-term debt − related party	(167,000)	(554,000)	(1,373,000)	(1,615,000)
Loss on early extinguishment of debt	(621,000)	0	(621,000)	0
Interest and other income, net	2,562,000	1,084,000	6,862,000	1,866,000
Total other income (expense), net	1,774,000	530,000	4,868,000	251,000
Loss before income taxes	(26,034,000)	(31,958,000)	(96,736,000)	(90,990,000)
Income tax expense	(1,003,000)	0	(1,003,000)	0
Net loss	$ (27,037,000)	$ (31,958,000)	$ (97,739,000)	$ (90,990,000)
Net loss per share − basic (in dollars per share)	$ (0.55)	$ (0.65)	$ (1.99)	$ (1.86)
Net loss per share − diluted (in dollars per share)	$ (0.55)	$ (0.65)	$ (1.99)	$ (1.86)
Weighted-average number of shares used in computed net loss per share − basic	49,212,126	48,921,928	49,103,351	48,827,503
Weighted-average number of shares used in computed net loss per share − diluted	49,212,126	48,921,928	49,103,351	48,827,503
Other comprehensive income (loss)
Unrealized gain (loss) on marketable securities	$ 870,000	$ (828,000)	$ 3,233,000	$ (4,634,000)
Comprehensive loss	$ (26,167,000)	$ (32,786,000)	$ (94,506,000)	$ (95,624,000)
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]			Collaborative Arrangement [Member]	Collaborative Arrangement [Member]

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Accrued expenses and other current liabilities:
Accrued research and development	$ 7,399	$ 9,824
Accrued compensation and benefits	5,974	6,831
Other	2,111	3,114
Total accrued expenses and other current liabilities	$ 15,484	$ 19,769

Collaboration and license agreements

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Collaboration and license agreements

Roche Collaboration and License Agreement

In March 2016, the Company entered into a license agreement with Roche, which was amended in June 2016 and amended further in March 2017. The Company and Roche amended and restated that agreement (as so amended) in December 2018. This amended and restated agreement is referred to as the Roche Agreement. Under the Roche Agreement, the Company and Roche agreed to collaborate in the research, development, manufacture and commercialization of target-binding degrader medicines using the Company’s proprietary TORPEDO platform for the treatment of cancers and other indications. Under the Roche Agreement, the Company may elect to opt into certain co-development rights, in which case

the Company will receive an increased royalty rate on future product sales from products directed to that target. In addition, if the Company opts into certain co-detailing rights, it is also entitled to reimbursement of certain commercialization costs. Upon entry into the Roche Agreement, the Company received additional upfront consideration of $40.0 million from Roche.

In November 2020, the Company signed a further amendment, the effect of which was to provide that the parties would develop up to five potential targets, with Roche maintaining its option rights to license and commercialize products directed to those targets. The November 2020 amendment also provides a mechanism through which the Company and Roche can mutually agree to terminate the Roche Agreement on a target-by-target basis by the entry into a Mutual Target Termination Agreement. Upon the entry into a Mutual Target Termination Agreement, the Roche Agreement provides that all rights and responsibilities for know-how and other intellectual property in support of products that use inhibition as their mode of action revert to Roche and all rights and responsibilities for know-how and other intellectual property in support of products that use degradation as their mode of action revert to the Company. In support of this allocation of rights, Roche provides the Company, and the Company provides Roche, with a perpetual irrevocable, fully paid up, exclusive (even as to party granting the license), sublicensable (including in multiple tiers) license to the patents and know-how that are allocated to a party under a Mutual Target Termination Agreement. As the research activities with Roche have progressed and evolved over time, there are now three targets on which the parties continue to collaborate, with Roche maintaining its option rights to license and commercialize products directed to those three targets.

Under the Roche Agreement, the Company receives annual research plan payments of $1.0 million for up to three years for each active research plan. For certain targets, Roche is required to pay the Company fees of $2.0 million and $3.0 million upon the progression of targets to the lead series identification achievement and good laboratory practice toxicology study phase, respectively. Finally, adjustments were made to the option exercise fees, whereby targets that have progressed through standard good laboratory practice, or GLP, toxicology studies at the time of exercise now have option exercise fees of $7.0 million to $12.0 million and those progressed through Phase 1 trials have option exercise fees of $20.0 million. For each target option exercised by Roche, the Company is eligible to receive milestone payments ranging from $260.0 million to $275.0 million upon the achievement of certain development and commercial milestones with respect to corresponding products, subject to certain reductions and exclusions based on intellectual property coverage. Roche is also required to pay the Company up to $150.0 million per target in one-time sales-based milestone payments upon the achievement of specified levels of net sales of a product directed to such target. Finally, Roche is required to pay the Company tiered royalties ranging from the mid-single digits to mid-teen percentages on net sales of products sold by Roche pursuant to its exercise of its option rights, subject to certain reductions. For sales of products for which the Company exercises its co-development right, the applicable royalty rates will be increased by a low-single digit percentage.

The collaboration is managed by a joint research committee. The Company has control over the joint research committee prior to Roche’s exercise of its option rights as to a particular target, with Roche assuming control of the joint research committee thereafter. Roche may terminate the Roche Agreement on a target-by-target or product-by-product basis under several scenarios upon at least 90 days’ prior written notice.

Roche Agreement accounting

At commencement, the Company identified twelve performance obligations within the Roche Agreement, represented by the six potential research and development targets then included in the collaboration and the option rights held by Roche for each of those six targets. A non-exclusive royalty-free license to use the Company’s intellectual property to conduct research and development activities and participation on joint research committee were identified as promised services. However, the Company determined that the research and development license and research and development services were not distinct from one another, and participation on the joint research committee was determined to be quantitatively and qualitatively immaterial.

The total transaction price of the Roche Agreement is allocated to the performance obligations based on their relative standalone selling price. The allocated transaction price is recognized as revenue from collaboration agreements in one of two ways:

•Research and development targets: The Company recognizes the portion of the transaction price allocated to each of the research and development performance obligations as the research and development services are provided, using an input method, in proportion to costs incurred to date for each research development target as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation related to said research and development target. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation.

•Option rights: The transaction price allocated to the options rights, which are considered material rights, is recognized in the period that Roche elects to exercise or elects to not exercise its option right to license and commercialize the underlying research and development target.

The following table summarizes the allocation of the total transaction price to the identified performance obligations under the arrangement, and the amount of the transaction price unsatisfied as of September 30, 2023 (in thousands):


	Transaction Price Allocated		Transaction Price Unsatisfied
Performance obligations:
Research and development targets	$	61,149	$	17,722
Option rights	6,757		1,670
Total	$	67,906	$	19,392

Amounts due to the Company that have not yet been received are recorded as accounts receivable and amounts received that have not yet been recognized as revenue are recorded as deferred revenue on the Company’s condensed consolidated balance sheet.

Betta Pharma License and Collaboration Agreement

On May 29, 2023, the Company entered into a license and collaboration agreement, or the Betta License Agreement, with Betta Pharma to collaborate on the development and commercialization of CFT8919 in mainland China, Hong Kong SAR, Macau SAR and Taiwan, or the Licensee Territory, with the Company retaining rights to CFT8919 in the rest of the world other than the Licensee Territory, or the C4T Territory.

Under the terms of the Betta License Agreement, the Company grants Betta Pharma an exclusive license under certain of the Company's intellectual property rights to develop, manufacture and commercialize CFT8919 for all uses in humans in the Licensee Territory. Betta Pharma is responsible for all development, regulatory approval, manufacturing and commercialization costs in the Licensee Territory except where Betta Pharma acts as the Company's agent in the Licensee Territory in connection with a global trial sponsored by the Company. As part of the collaboration, Betta Pharma made an upfront cash payment of $10.0 million and has agreed to make up to $357.0 million in aggregate milestone payments, plus tiered royalties on net sales of CFT8919 in the Licensee Territory. These payments are subject to a withholding tax by the State Taxing Authority of the People's Republic of China. Royalties payable from Betta Pharma to the Company range from low to mid double-digit percent, subject to certain reductions under certain circumstances as described in the Betta License Agreement. In addition, as part of the collaboration, the Company has agreed to make milestone payments to Betta Pharma of up to $40.0 million following the Company's receipt of approval of a New Drug Application for CFT8919 from the FDA, with the milestone amount based on the percentage of patients in contemplated clinical trials that were enrolled by Betta Pharma and the line of therapy of the approval. In addition, the Company has agreed to pay Betta Pharma tiered royalties on net sales of CFT8919 in the C4T Territory in the low single digit percent range, subject to reductions under certain circumstances as described in the Betta License Agreement.

In connection with the execution of the Betta License Agreement, the Company, Betta Pharma, and an affiliate of Betta Pharma, (Betta Investment (Hong Kong) Limited, or Betta Investment), entered into a Stock Purchase Agreement dated May 29, 2023, or the Betta Stock Purchase Agreement, and together with the Betta License Agreement, or the Betta Agreements, pursuant to which Betta Investment agreed to purchase 5,567,928 shares of the Company's common stock, or the Shares, for an aggregate purchase price of approximately $25.0 million, or $4.49 per share, which represented a 25% premium over the 60-trading-day volume weighted average closing price as of two trading days prior to the effective date of the Betta Stock Purchase Agreement. Closing under the Betta Stock Purchase Agreement had not occurred as of the date of filing (November 1, 2023).

The collaboration is managed by a joint steering committee, which is composed of representatives from both Betta Pharma and the Company. Following the completion of the dose escalation phase of the Phase 1 trial of CFT8919, Betta Pharma may terminate the Betta License Agreement for convenience upon at least 90 days’ prior written notice. Each party also has various termination rights under certain circumstances, including but not limited to regulatory safety stoppages, patent challenges, or a material breach by the other party, subject to certain conditions.

Betta Agreements accounting

The Company expects to recognize revenue under the Betta Agreements from one type of arrangement, the licensing agreement. The Betta Agreements will consist of the following activities: (1) license of intellectual property, (2) clinical manufacturing supply agreement, and (3) manufacturing technology transfer, and (4) commercial manufacturing supply

agreement. As of September 30, 2023, the total transaction price is currently $10.0 million, consisting of the $10.0 million upfront cash consideration. Revenue recognition associated with the Betta Agreements is expected to commence upon the delivery of clinical supply under the clinical manufacturing supply agreement, which has not been executed as of September 30, 2023. The Company has collected the full $10.0 million upfront payment from Betta Pharma, and during the three months ended September 30, 2023, the Company made the related withholding tax payment of $1.0 million to the Chinese tax authorities.

During the three and nine months ended September 30, 2023, no revenue has been recognized under the Betta Agreements. Amounts received or due to the Company that have not yet been recognized as revenue are recorded in deferred revenue on the Company’s condensed consolidated balance sheet.

Biogen Collaboration Research and License Agreement

In December 2018, the Company entered into a collaboration research and license agreement, or the Biogen Agreement, with Biogen. In February 2020, the Company and Biogen amended the Biogen Agreement to provide further clarity around Biogen’s ownership of target binding moieties (which are portions of molecules), and any related intellectual property that are directed at or bind to collaboration targets. This amendment further provided that Biogen licenses to the Company rights to use these Biogen target binding moieties and any related intellectual property as needed in order to conduct the research and development activities contemplated under the Biogen Agreement. Pursuant to the terms of the Biogen Agreement, the Company and Biogen agreed to collaborate on research activities to develop novel treatments for neurological conditions such as Alzheimer's disease and Parkinson's disease through medicines that rely on target protein degradation, or TPD, as their mode of action, all of which are created using the Company’s degrader technology. Under the terms of the Biogen Agreement, the Company was engaged to develop TPD therapeutics that utilize degrader technology for up to five target proteins over a period of 54 months, ending in June 2023. On a target-by-target basis, after successful completion of a defined target evaluation period, Biogen assumes full rights and responsibility for continued development of each target. As of September 30, 2023, the research term of the Biogen Agreement has expired, though certain research activities on the nominated targets will continue for an additional time period, as contemplated by the Biogen Agreement.

In exchange for the non-exclusive research license from Biogen, as well as a $45.0 million nonrefundable upfront payment, the Company has granted a license to develop, commercialize, and manufacture products related to each of the targets (which is contingent on not cancelling the agreement), performs initial research services for drug discovery, has provided a non-exclusive research and commercial license to its intellectual property, and participates on the joint steering committee, or the Biogen JSC. The Company was also obligated to participate in early research activities for other potential targets or sandbox activities, at Biogen’s election up to a maximum amount; any work performed for these services is reimbursed by Biogen, and Biogen reimburses the Company for certain full-time equivalent, or FTE, costs. The Company’s obligations under the sandbox activities were completed as of August 31, 2021. For any target, following the achievement of development candidate criteria and prior to any IND-enabling study, Biogen will bear all costs and expenses of and will have sole discretion and decision-making authority with respect to the performance of further activities with respect to any degrader under development under the Biogen Agreement and all products that incorporate that degrader. Biogen is also required to pay the Company up to $35.0 million per target in development milestones and $26.0 million per target in one-time sales-based payments for the first product to achieve certain levels of net sales. In addition, Biogen is required to pay the Company royalties on a licensed product-by-licensed product basis, on worldwide net product sales. All milestone and sales-based payments are made after the Company has met the defined criteria in the joint research plan for that target, at which time Biogen will have control of the products related to the targets for commercialization; the receipt of these payments is contingent on the further development of products directed to the targets to commercialization by Biogen, without any additional research and development efforts from the Company.

The collaboration is managed by the Biogen JSC, which Biogen has control over, and Biogen may terminate the Biogen Agreement on a target-by-target or product-by-product basis under several scenarios, upon at least 90 days’ prior written notice.

Biogen Agreement accounting

The Company recognizes revenue under the Biogen Agreement from two types of services: (i) research and development services, and (ii) sandbox activities, which are discovery-type research services.

•Research and development services: The Company identified one performance obligation at the outset of the Biogen Agreement, representing a combined performance obligation consisting of (1) the licenses, (2) the research activities for the target evaluation phase for all five targets, and (3) the joint research plan phase for each target. The Company determined that the licenses and research activities were not distinct from one another, as the licenses have limited value without the performance of the research activities by the Company. Participation on the Biogen JSC to oversee the research activities and the technology transfer associated with

the Biogen License Agreement were determined to be quantitatively and qualitatively immaterial and therefore are excluded from performance obligations. The Company recognizes the transaction price allocated to this performance obligation as the research and development services are provided, using an input method, in proportion to costs incurred to date for each research development target as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation related to said research and development target. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation.

•Sandbox activities: Biogen had the option to fund sandbox activities in exchange for consideration at market rates, whereby the Company would perform discovery-type research at Biogen’s election to develop other potential targets that may be used as replacement targets for the initially nominated targets or two additional targets under the Biogen Agreement. Revenues earned under this option were recognized as services were performed and were not included in the transaction price allocated to the performance obligation described above. The Company recognized FTE reimbursement received for sandbox activities as revenue as incurred each quarter. As noted above, sandbox activities fully concluded on August 31, 2021.

As of September 30, 2023, the total transaction price of the Biogen Agreement of $55.0 million is allocated to the research and development services performance obligation and $3.7 million of the allocated transaction price remains unsatisfied. As contemplated by the Biogen Agreement, certain research activities on the nominated targets will continue for a period of time beyond the June 2023 end of the research term.

Amounts due to the Company that have not yet been received are recorded as accounts receivable and amounts received that have not yet been recognized as revenue are recorded in deferred revenue on the Company’s condensed consolidated balance sheet.

Calico Collaboration and License Agreement

In March 2017, the Company entered into a collaboration and license agreement, or the Calico Agreement, with Calico whereby the Company and Calico agreed to collaborate to develop and commercialize small molecule protein degraders for diseases of aging, including cancer, for a five-year period ending in March 2022. In August 2021, the Company provided an extension option to Calico, which Calico exercised in September 2021, resulting in a $1.0 million extension payment to extend the research term with respect to a certain program for up to a one-year period that ended in March 2023. In addition, Calico reimbursed the Company for a number of FTEs, depending on the stage of the research, at specified market rates. As of March 13, 2023, the research term of the Calico Agreement has expired, and the Company's research activities associated with the agreement are substantially complete.

Under the Calico Agreement, Calico paid an upfront amount of $5.0 million and certain annual payments totaling $5.0 million through June 30, 2020 and paid target initiation fees and reimbursed the Company for a number of FTEs, depending on the stage of the research, at specified market rates. For each target, the Company is eligible to receive up to $132.0 million in potential development and commercial milestone payments, on sales of all products resulting from the collaboration efforts. Calico is also required to pay the Company up to $65.0 million in one-time sales-based payments for the first product to achieve certain levels of net sales. In addition, Calico is required to pay the Company royalties, at percentages in the mid-single digits, on a licensed product-by-licensed product basis, on worldwide net product sales. All milestone and sales-based payments are made after the Company has met the defined criteria in the joint research plan for that target, at which time Calico will have control of the products related to targets for commercialization; the receipt of these payments by the Company is contingent on the further development of the targets to commercialized products by Calico, without any additional research and development efforts required by the Company.

As of September 30, 2023, the total transaction price of the Calico Agreement of $13.0 million was allocated to the research and development services performance obligation and the transaction price has been fully allocated and satisfied.

Amounts due to the Company that have not yet been received are recorded as accounts receivable on the Company’s condensed consolidated balance sheet.

Summary of revenue recognized from collaboration agreements

Revenue from collaboration agreements for the three and nine months ended September 30, 2023 and 2022 in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue from collaboration agreements:
Roche Agreement	$	8,223	$	875	$	8,736	$	4,548
Biogen Agreement	2,849		4,100		7,689		18,350
Calico Agreement	—		1,779		1,070		5,344
Total revenue from collaboration agreements	$	11,072	$	6,754	$	17,495	$	28,242

Financial information related to the collaboration and license agreements consisted of the following in the Company’s condensed consolidated balance sheet as of September 30, 2023 (in thousands):


	Accounts Receivable		Deferred Revenue, Current		Deferred Revenue, Net of Current		Deferred Revenue, Total
Supplemental information:
Roche Agreement	$	500	$	2,464	$	11,845	$	14,309
Biogen Agreement	—		3,738		—		3,738
Calico Agreement	—		—		—		—
Betta Agreements	—		2,222		7,778		10,000
Total	$	500	$	8,424	$	19,623	$	28,047

Financial information related to the collaboration and license agreements consisted of the following in the Company’s condensed consolidated balance sheet as of December 31, 2022 (in thousands):


	Accounts Receivable		Deferred Revenue, Current		Deferred Revenue, Net of Current		Deferred Revenue, Total
Supplemental information:
Roche Agreement	$	417	$	4,649	$	16,895	$	21,544
Biogen Agreement	—		11,427		—		11,427
Calico Agreement	1,056		542		—		542
Total	$	1,473	$	16,618	$	16,895	$	33,513

Supplemental financial information related to the collaboration and license agreements for the three and nine months ended September 30, 2023 and 2022 are (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue recognized that was included in the contract liability at the beginning of the period	$	11,028	$	5,517	$	16,923	$	24,005
Revenue recognized from performance obligations fully or partially satisfied in previous periods	$	43	$	—	$	43	$	518

As of September 30, 2023, the aggregate amount of the transaction price allocated to performance obligations under the Roche Agreement, the Biogen Agreement, and the Betta Agreements that were partially unsatisfied was $33.1 million.

Commitment and contingencies	9 Months Ended
Commitment and contingencies	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Commitments and contingencies Legal proceedings The Company is not currently party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses as incurred the costs related to such legal proceedings.

Nature of the business and basis of presentation (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss	$ 97,739	$ 90,990
Accumulated deficit	493,629		$ 395,890
Cash, cash equivalents and marketable securities	$ 246,400

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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-Paragraph 3
-Subparagraph (c)
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-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
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-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
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-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
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-URI https://asc.fasb.org//1943274/2147483443/250-10-50-8

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
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-URI https://asc.fasb.org//1943274/2147483443/250-10-50-9

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
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-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480167/946-830-55-11

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 205
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-Section 45
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480767/946-205-45-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483581/946-220-45-7

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(16))
-Publisher FASB
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Reference 12: 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 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(9))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(1)(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 19
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-19

Reference 16: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482765/220-10-50-6

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Accrued expenses and other current liabilities (Tables)

9 Months Ended

Sep. 30, 2023

Payables and Accruals [Abstract]

Summary of accrued liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):


	September 30, 2023		December 31, 2022
Accrued expenses and other current liabilities:
Accrued research and development	$	7,399	$	9,824
Accrued compensation and benefits	5,974		6,831
Other	2,111		3,114
Total accrued expenses and other current liabilities	$	15,484	$	19,769

Stock-based compensation - Schedule of stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 8,200	$ 6,011	$ 20,876	$ 23,097
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3,906	2,636	9,133	10,024
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 4,294	$ 3,375	$ 11,743	$ 13,073

Collaboration and license agreements - Summary of allocation of transaction price (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Transaction Price Allocated	$ 67,906
Transaction Price Unsatisfied	19,392
Research and development targets
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Transaction Price Allocated	61,149
Transaction Price Unsatisfied	17,722
Option rights
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Transaction Price Allocated	6,757
Transaction Price Unsatisfied	$ 1,670

Collaboration and license agreements (Tables)

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of allocation of transaction price


	Transaction Price Allocated		Transaction Price Unsatisfied
Performance obligations:
Research and development targets	$	61,149	$	17,722
Option rights	6,757		1,670
Total	$	67,906	$	19,392

Schedule of revenue from collaboration agreements


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue from collaboration agreements:
Roche Agreement	$	8,223	$	875	$	8,736	$	4,548
Biogen Agreement	2,849		4,100		7,689		18,350
Calico Agreement	—		1,779		1,070		5,344
Total revenue from collaboration agreements	$	11,072	$	6,754	$	17,495	$	28,242

Schedule of financial information related to collaboration and license agreements

Financial information related to the collaboration and license agreements consisted of the following in the Company’s condensed consolidated balance sheet as of September 30, 2023 (in thousands):


	Accounts Receivable		Deferred Revenue, Current		Deferred Revenue, Net of Current		Deferred Revenue, Total
Supplemental information:
Roche Agreement	$	500	$	2,464	$	11,845	$	14,309
Biogen Agreement	—		3,738		—		3,738
Calico Agreement	—		—		—		—
Betta Agreements	—		2,222		7,778		10,000
Total	$	500	$	8,424	$	19,623	$	28,047

Financial information related to the collaboration and license agreements consisted of the following in the Company’s condensed consolidated balance sheet as of December 31, 2022 (in thousands):


	Accounts Receivable		Deferred Revenue, Current		Deferred Revenue, Net of Current		Deferred Revenue, Total
Supplemental information:
Roche Agreement	$	417	$	4,649	$	16,895	$	21,544
Biogen Agreement	—		11,427		—		11,427
Calico Agreement	1,056		542		—		542
Total	$	1,473	$	16,618	$	16,895	$	33,513

Schedule of supplemental financial information related to collaboration and license agreements

Supplemental financial information related to the collaboration and license agreements for the three and nine months ended September 30, 2023 and 2022 are (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue recognized that was included in the contract liability at the beginning of the period	$	11,028	$	5,517	$	16,923	$	24,005
Revenue recognized from performance obligations fully or partially satisfied in previous periods	$	43	$	—	$	43	$	518

Loss per share (Tables)

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Schedule of diluted net loss per share attributable to common stockholders

The Company excluded the following potential common shares presented based on amounts outstanding at period end from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect:


	As of September 30,
	2023	2022
Anti-dilutive common stock equivalents:
Options to purchase common stock	9,868,099	6,952,795

Total anti-dilutive common stock equivalents	9,868,099	6,952,795

Schedule of basic and diluted loss per share


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Numerator:
Net loss	$	(27,037)	$	(31,958)	$	(97,739)	$	(90,990)
Denominator:
Weighted-average number of shares used in computed net loss per share − basic and diluted	49,212,126		48,921,928		49,103,351		48,827,503
Net loss per share − basic and diluted	$	(0.55)	$	(0.65)	$	(1.99)	$	(1.86)

Marketable securities - Narrative (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Marketable Securities [Abstract]
Allowance for credit loss	$ 0	$ 0

Long-term debt – related party (Tables)

9 Months Ended

Sep. 30, 2023

Debt Disclosure [Abstract]

Schedule of long-term debt

Long-term debt – related party consisted of the following (in thousands):


	December 31, 2022
Term Loan — related party, net of unamortized debt issuance costs and debt discount of $1,018 at December 31, 2022	$	11,482
Less: current portion	2,287
Total long-term debt — related party, net of current and discount	9,195

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

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+ Details

Fair value measurements (Tables)

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Schedule of financial assets measured at fair value on a recurring basis

The following table presents information about the Company’s financial assets measured at fair value on a recurring basis and indicates the level of the fair value hierarchy utilized to determine such fair values as of September 30, 2023 (in thousands):


	Fair Value		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	43,118	$	43,118	$	—	$	—
Corporate debt securities	9,927		—		9,927		—
U.S. Treasury securities	7,676		—		7,676		—
Marketable securities:
Corporate debt securities	126,996		—		126,996		—
U.S. government debt securities	48,548		—		48,548		—
U.S. Treasury securities	9,911		—		9,911		—
Total cash equivalents and marketable securities	$	246,176	$	43,118	$	203,058	$	—

There have been no transfers between fair value levels during the nine months ended September 30, 2023.

The following table sets forth the fair value of the Company’s financial assets by level within the fair value hierarchy at

December 31, 2022 (in thousands):


	Fair Value		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	28,705	$	28,705	$	—	$	—

U.S. Treasury securities	799		—		799		—
Marketable securities:
Corporate debt securities	234,327		—		234,327		—
U.S. government debt securities	47,641		—		47,641		—
U.S. Treasury securities	25,393		—		25,393		—
Total cash equivalents and marketable securities	$	336,865	$	28,705	$	308,160	$	—

Property and equipment (Tables)

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment [Abstract]

Summary of property and equipment

Property and equipment consisted of the following (in thousands):


	September 30, 2023		December 31, 2022
Property and equipment:
Laboratory equipment	$	8,303	$	8,757
Leasehold improvements	4,766		4,682
Furniture and fixtures	1,181		1,181
Office equipment	621		529
Construction in progress	223		183
Computer equipment	98		191
Total property and equipment	15,192		15,523
Less: accumulated depreciation	(7,902)		(8,123)
Total property and equipment, net	$	7,290	$	7,400

Depreciation expense related to property and equipment is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Depreciation expense	$	447	$	415	$	1,450	$	1,155

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows used in operating activities:
Net loss	$ (97,739)	$ (90,990)
Adjustments to reconcile net loss to cash used in operating activities:
Stock-based compensation expense	20,876	23,097
Depreciation and amortization expense	1,450	1,155
Reduction in carrying amount of right-of-use asset	4,596	4,394
Net (accretion) amortization of (discounts) premiums on marketable securities	(2,817)	1,118
Amortization of debt discount − related party	405	534
Loss on early extinguishment of debt	621	0
Other	120	0
Changes in operating assets and liabilities:
Accounts receivable	973	4,229
Prepaid expenses and other current and long-term assets	1,404	217
Accounts payable	104	(2,257)
Accrued expenses and other current liabilities	(3,866)	2,391
Operating lease liability	(3,489)	575
Deferred revenue	(5,467)	(21,274)
Net cash used in operating activities	(82,829)	(76,811)
Cash flows provided by investing activities:
Proceeds from maturities of marketable securities	219,975	216,382
Purchases of marketable securities	(92,020)	(163,238)
Purchases of property and equipment, net	(1,551)	(4,006)
Net cash provided by investing activities	126,404	49,138
Cash flows (used in) provided by financing activities:
Payment of long-term debt − related party	(12,500)	0
Payments for repurchase of common stock for tax withholding	(110)	0
Proceeds from exercise of stock options	58	730
Other	369	370
Net cash (used in) provided by financing activities	(12,183)	1,100
Net change in cash, cash equivalents and restricted cash	31,392	(26,573)
Cash, cash equivalents and restricted cash at beginning of period	33,033	79,403
Cash, cash equivalents and restricted cash at end of period	64,425	52,830
Reconciliation of cash, cash equivalents and restricted cash:
Cash, cash equivalents and restricted cash at end of period	64,425	52,830
Less: restricted cash	(3,454)	(3,279)
Cash and cash equivalents at end of the period	60,971	49,551
Supplemental disclosures of cash flow information:
Cash paid for income taxes	1,003	0
Cash paid for interest − related party	990	1,203
Cash paid for leases	6,421	5,083
Supplemental disclosures of non-cash investing and financing activities:
Capital expenditures in accounts payable and accrued expenses	54	1,455
Operating lease liabilities arising from obtaining right-of-use assets	$ 0	$ 44,067

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value per share (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	49,259,870	48,966,216
Common stock, shares outstanding	49,259,870	48,966,216

Income taxes	9 Months Ended
Income taxes	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income taxes	Income taxesAs of December 31, 2022, the Company recorded no income tax provision or benefit due to losses generated in the U.S. where no benefit was recorded due to the valuation allowance. The Company continues to maintain a full valuation allowance for its U.S. federal and state deferred tax assets as of September 30, 2023. The Company’s effective tax rate in the nine months ended September 30, 2023 was impacted by the Chinese withholding tax obligation related to the upfront payment received in connection with the Betta License Agreement, as described in Note 8, Collaboration and license agreement, to the unaudited condensed consolidated financial statements included elsewhere in this Quarterly Report on Form 10-Q, which resulted in a tax provision of $1.0 million and an effective tax rate of (1.0)%.

- 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
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//740/tableOfContent

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-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Long-term debt – related party

9 Months Ended

Sep. 30, 2023

Debt Disclosure [Abstract]

Long-term debt – related party

Long-term debt – related party consisted of the following (in thousands):


	December 31, 2022
Term Loan — related party, net of unamortized debt issuance costs and debt discount of $1,018 at December 31, 2022	$	11,482
Less: current portion	2,287
Total long-term debt — related party, net of current and discount	9,195

On June 5, 2020, contemporaneously with the completion of its Series B Financing, the Company entered into a Credit Agreement, or the Credit Agreement, with Perceptive Credit Holdings III, LP, an affiliate of Perceptive Advisors LLC, or Perceptive, that provided for an aggregate principal borrowing amount of up to $20.0 million, available in two tranches of $12.5 million and $7.5 million. Perceptive was considered a related party to the Company based on its ownership of the Company’s common stock at inception of the Credit Agreement.

In June 2020, the Company drew down on the first tranche of $12.5 million, or the Term Loan. The Company elected not to draw down the second tranche, which expired on June 30, 2021.

On May 17, 2023, the Company entered into an amendment to the Credit Agreement pursuant to which the Company and its lender agreed to replace the LIBOR benchmark with SOFR, which is regulated by the Federal Reserve Bank of New York. The Company amended its Credit Agreement due to the Financial Conduct Authority's planned phase-out of LIBOR on June 30, 2023. The use of the SOFR rate became effective as of July 1, 2023.

In July 2023, the Company's obligation to pay a prepayment fee was extinguished based on the terms of the Credit Agreement. On July 26, 2023, the Company elected to repay the remaining outstanding principal balance on the Term Loan.In connection with the repayment of the outstanding balance on the Term Loan, the liens on substantially all of the Company's assets were released. The Company incurred a $0.6 million loss on the extinguishment of this debt.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 60,971	$ 29,754
Marketable securities, current	155,598	246,399
Accounts receivable	500	1,473
Prepaid expenses and other current assets	6,617	9,931
Total current assets	223,686	287,557
Marketable securities, non-current	29,857	60,962
Property and equipment, net	7,290	7,400
Right-of-use asset	65,520	70,116
Restricted cash	3,454	3,279
Other assets	3,206	1,526
Total assets	333,013	430,840
Current liabilities:
Accounts payable	1,276	1,172
Accrued expenses and other current liabilities	15,484	19,769
Deferred revenue, current	8,424	16,618
Operating lease liability, current	5,087	4,700
Long-term debt − related party, current and net of discount	0	2,287
Total current liabilities	30,271	44,546
Deferred revenue, net of current	19,623	16,895
Operating lease liability, net of current	67,095	70,970
Long-term debt − related party, net of current and discount	0	9,195
Total liabilities	116,989	141,606
Commitments and contingencies (see Note 11)
Stockholders’ equity:
Preferred stock, par value of $0.0001 per share; 10,000,000 shares authorized, and no shares issued or outstanding as of September 30, 2023 and December 31, 2022, respectively	0	0
Common stock, par value of $0.0001 per share; 150,000,000 shares authorized, and 49,259,870 and 48,966,216 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	5	5
Additional paid-in capital	710,552	689,256
Accumulated other comprehensive loss	(904)	(4,137)
Accumulated deficit	(493,629)	(395,890)
Total stockholders’ equity	216,024	289,234
Total liabilities and stockholders’ equity	$ 333,013	$ 430,840

Loss per share - Schedule of diluted net loss per share attributable to common stockholders (Details) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	9,868,099	6,952,795
Options to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	9,868,099	6,952,795

Leases	9 Months Ended
Leases	Sep. 30, 2023
Leases [Abstract]
Leases	LeasesThe Company leases office and laboratory space under a non-cancelable operating lease. In addition, the Company subleases a portion of its office and laboratory space. There have been no material changes to the Company’s lease or sublease during the nine months ended September 30, 2023. For additional information, please read Note 6, Leases, to the audited condensed consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2022.

Fair value measurements

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Fair value measurements


	Fair Value		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	43,118	$	43,118	$	—	$	—
Corporate debt securities	9,927		—		9,927		—
U.S. Treasury securities	7,676		—		7,676		—
Marketable securities:
Corporate debt securities	126,996		—		126,996		—
U.S. government debt securities	48,548		—		48,548		—
U.S. Treasury securities	9,911		—		9,911		—
Total cash equivalents and marketable securities	$	246,176	$	43,118	$	203,058	$	—

There have been no transfers between fair value levels during the nine months ended September 30, 2023.

The following table sets forth the fair value of the Company’s financial assets by level within the fair value hierarchy at

December 31, 2022 (in thousands):


	Fair Value		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	28,705	$	28,705	$	—	$	—

U.S. Treasury securities	799		—		799		—
Marketable securities:
Corporate debt securities	234,327		—		234,327		—
U.S. government debt securities	47,641		—		47,641		—
U.S. Treasury securities	25,393		—		25,393		—
Total cash equivalents and marketable securities	$	336,865	$	28,705	$	308,160	$	—

The Company classifies its money market funds, which are valued based on quoted market prices in active markets, with no valuation adjustment, as Level 1 assets within the fair value hierarchy.

Marketable securities consist of U.S. Treasury securities, U.S. government debt securities, and corporate debt securities, all of which are classified as available-for-sale pursuant to ASC 320, Investments – Debt and Equity Securities. Marketable securities are classified within Level 2 of the fair value hierarchy because pricing inputs are other than quoted prices in active markets, which are either directly or indirectly observable as of the reporting date, and fair value is determined using models or other valuation methodologies on a recurring basis.

- 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

Summary of significant accounting policies (Policies)	9 Months Ended
Summary of significant accounting policies (Policies)	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of presentation	The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or U.S. GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or the SEC, regarding interim financial reporting, and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements.
Consolidation	These condensed consolidated financial statements include the accounts of C4 Therapeutics, Inc. and its subsidiary, C4T Securities Corporation. All intercompany balances and transactions have been eliminated in consolidation.
Unaudited interim financial information	Unaudited interim financial information The accompanying condensed consolidated balance sheet as of September 30, 2023, the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022, the condensed consolidated statements of stockholders’ equity for the three and nine months ended September 30, 2023 and 2022, and the condensed consolidated statements of cash flows for the nine months ended September 30, 2023 and 2022, and the related interim disclosures are unaudited. These unaudited condensed consolidated financial statements include all adjustments necessary, consisting of only normal recurring adjustments, to fairly state the financial position and the results of the Company’s operations and cash flows for interim periods in accordance with U.S. GAAP. Interim period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of and for year ended December 31, 2022, and notes thereto, which are included in the Company’s Annual Report on Form 10-K that was filed with the SEC on February 23, 2023.
Use of estimates	Use of estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. This process may result in actual results differing materially from those estimated amounts used in the preparation of the condensed consolidated financial statements if these results differ from historical experience or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, amounts and timing of revenues recognized under the Company’s research and development collaboration arrangements, prepaid and accrued research and development expense, incremental borrowing rate used in the measurement of lease liabilities, and estimated volatility used in fair valuation of stock options. The Company assesses estimates on an ongoing basis; however, actual results could materially differ from those estimates.

Stock-based compensation - Narrative (Details) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted (in shares)	4,427,620
Stock options granted, weighted average exercise price (in dollars per share) \| $ / shares	$ 3.89
Stock options granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 2.86
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs \| $	$ 42.9
Expected to be recognized over a weighted average period	2 years 4 months 24 days
Performance-based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs \| $	$ 6.4
Units vested (in shares)	135,301
Share-based compensation, number of common stock issuable per RSU vested (in shares)	1
Number of shares retained to cover statutory minimum withholding taxes	17,556
Time-based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs \| $	$ 3.4
Expected to be recognized over a weighted average period	3 years 4 months 24 days
Units vested (in shares)	0

Loss per share - Schedule of basic and diluted loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net loss	$ (27,037)	$ (35,922)	$ (34,780)	$ (31,958)	$ (27,412)	$ (31,620)	$ (97,739)	$ (90,990)
Denominator:
Weighted-average number of shares used in computed net loss per share − basic	49,212,126			48,921,928			49,103,351	48,827,503
Weighted-average number of shares used in computed net loss per share − diluted	49,212,126			48,921,928			49,103,351	48,827,503
Net loss per share − basic (in dollars per share)	$ (0.55)			$ (0.65)			$ (1.99)	$ (1.86)
Net loss per share − diluted (in dollars per share)	$ (0.55)			$ (0.65)			$ (1.99)	$ (1.86)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

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-Topic 250
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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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- Definition

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

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+ Details

Nature of the business and basis of presentation	9 Months Ended
Nature of the business and basis of presentation	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the business and basis of presentation	Nature of the business and basis of presentation C4 Therapeutics, Inc., or, together with its subsidiary, the Company, is a clinical-stage biopharmaceutical company dedicated to the advancement of targeted protein degradation science to develop a new generation of small-molecule medicines to transform how disease is treated. The Company leverages its proprietary technology platform, TORPEDO (Target ORiented ProtEin Degrader Optimizer), to efficiently design and optimize small-molecule medicines that harness the body’s natural protein recycling system to rapidly degrade disease-causing protein, offering the potential to overcome drug resistance, drug undruggable targets, and improve patient outcomes. The Company uses its TORPEDO platform to advance multiple targeted oncology programs to the clinic while expanding its research platform to deliver the next wave of medicines for difficult-to-treat diseases. The Company was incorporated in Delaware on October 7, 2015 and has its principal office in Watertown, Massachusetts. Liquidity and capital resources Since its inception, the Company’s primary activities have been focused on research and development activities, building the Company’s intellectual property, recruiting and retaining personnel, and raising capital to support these activities. To date, the Company has funded its operations primarily with proceeds received from the sales of redeemable convertible preferred stock, public offerings of the Company’s common stock, through its collaboration agreements, and debt financing. The Company has incurred recurring losses since its inception, including net losses of $97.7 million and $91.0 million for the nine months ended September 30, 2023 and 2022, respectively. In addition, as of September 30, 2023, the Company had an accumulated deficit of $493.6 million. To date, the Company has not generated any revenue from product sales as none of its product candidates have been approved for commercialization. The Company expects to continue to generate operating losses for the foreseeable future. The Company expects that its cash, cash equivalents, and marketable securities of $246.4 million as of September 30, 2023 will be sufficient to fund its operations into the second half of 2025. Accordingly, the condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business. Risks and uncertainties The Company is subject to risks common to other life science companies in the early development stage including, but not limited to, uncertainty of ability to raise additional financing, product development and commercialization, development by its competitors of new technological innovations, dependence on key personnel, market acceptance of products, lack of marketing and sales history, product liability, protection of proprietary technology and intellectual property, and compliance with the Food and Drug Administration, or the FDA, and other government regulations. If the Company does not successfully advance its programs into and through human clinical trials and commercialize any of its product candidates either directly or through collaborations with other companies, the Company may be unable to produce product revenue or achieve profitability. There can be no assurance that the Company’s research and development efforts will be successful, adequate protection for the Company’s intellectual property will be obtained, any products developed will obtain necessary government regulatory approval, or any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies.

Fair value measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	$ 185,455	$ 307,361
Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	246,176	336,865
Recurring \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	126,996	234,327
Recurring \| U.S. government debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	48,548	47,641
Recurring \| U.S. Treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	9,911	25,393
Money market funds \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	43,118	28,705
Corporate debt securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	9,927
U.S. Treasury securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	7,676	799
Level 1 \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	43,118	28,705
Level 1 \| Recurring \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 1 \| Recurring \| U.S. government debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 1 \| Recurring \| U.S. Treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 1 \| Money market funds \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	43,118	28,705
Level 1 \| Corporate debt securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0
Level 1 \| U.S. Treasury securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Level 2 \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	203,058	308,160
Level 2 \| Recurring \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	126,996	234,327
Level 2 \| Recurring \| U.S. government debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	48,548	47,641
Level 2 \| Recurring \| U.S. Treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	9,911	25,393
Level 2 \| Money market funds \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Level 2 \| Corporate debt securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	9,927
Level 2 \| U.S. Treasury securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	7,676	799
Level 3 \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total cash equivalents and marketable securities	0	0
Level 3 \| Recurring \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 3 \| Recurring \| U.S. government debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 3 \| Recurring \| U.S. Treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	0	0
Level 3 \| Money market funds \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Level 3 \| Corporate debt securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0
Level 3 \| U.S. Treasury securities \| Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	$ 0	$ 0

Subsequent events	9 Months Ended
Subsequent events	Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent events	Subsequent eventsOn October 30, 2023, the Board of Directors approved the Company's decision to not advance CFT8634 beyond the Phase 1 dose escalation portion of the Phase 1/2 clinical trial. Costs associated with the decision to suspend the program are not expected to be material

Collaboration and license agreements - Schedule of revenue from collaboration agreements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue from collaboration agreements	$ 11,072	$ 6,754	$ 17,495	$ 28,242
Roche Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue from collaboration agreements	8,223	875	8,736	4,548
Biogen Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue from collaboration agreements	2,849	4,100	7,689	18,350
Calico Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue from collaboration agreements	$ 0	$ 1,779	$ 1,070	$ 5,344

- 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.

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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

Collaboration and license agreements - Narrative (Details)		1 Months Ended					3 Months Ended		9 Months Ended		40 Months Ended
	May 29, 2023 USD ($) $ / shares shares	Aug. 31, 2021 USD ($)	Nov. 30, 2020 USD ($) target	Feb. 29, 2020 USD ($) protein	Dec. 31, 2018 USD ($) target performanceObligation	Mar. 31, 2017 USD ($)	Sep. 30, 2023 USD ($) target performanceObligation	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) target performanceObligation	Sep. 30, 2022 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2022 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of performance obligations \| performanceObligation					12
Transaction price							$ 28,047,000		$ 28,047,000			$ 33,513,000
Revenue from collaboration agreements							11,072,000	$ 6,754,000	17,495,000	$ 28,242,000
Revenue recognized that was included in the contract liability at the beginning of the period							11,028,000	$ 5,517,000	16,923,000	$ 24,005,000
Transaction price allocated to performance obligation							67,906,000		$ 67,906,000
Foreign Tax Authority
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments for tax withholdings							$ 1,000,000
Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Written notice period for termination of agreement	90 days
Restated Roche Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional upfront consideration received					$ 40,000,000
Number of potential targets \| target			5		6
Number of targets \| target							3		3
Annual research plan payments receivables			$ 1,000,000
Annual research plan payments periods			3 years
Restated Roche Agreement \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Option exercise fees			$ 7,000,000
Written notice period for termination of agreement									90 days
Restated Roche Agreement \| Minimum \| Research, development and commercial milestones
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amount eligible to receive			260,000,000
Restated Roche Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Option exercise fees			12,000,000
Option exercise fees, through Phase 1 trials			20,000,000
Restated Roche Agreement \| Maximum \| Research, development and commercial milestones
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amount eligible to receive			275,000,000
Restated Roche Agreement \| Maximum \| One-time sales-based payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amount eligible to receive			150,000,000
Restated Roche Agreement \| Lead Series Identification Achievement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront fees			2,000,000
Restated Roche Agreement \| Good Laboratory Practice (“GLP”) Toxicology (“Tox”) Study Phase
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront fees			$ 3,000,000
Betta Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment	$ 10,000,000						$ 10,000,000
Number of shares authorized to be repurchased \| shares	5,567,928
Stock repurchase program, authorized amount	$ 25,000,000
Share price (in dollars per share) \| $ / shares	$ 4.49
Stock Repurchase Program, Premium Percentage	25.00%
Transaction price							10,000,000		$ 10,000,000
Revenue from collaboration agreements							$ 0		$ 0
Betta Agreements \| Research and development milestones
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amount eligible to receive	$ 357,000,000
Betta Agreements \| Drug Application Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amount eligible to receive	$ 40,000,000
Biogen License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets \| performanceObligation							5		5
Research agreement, period				54 months
Nonrefundable upfront payment				$ 45,000,000
Number of performance obligation \| performanceObligation							1		1
Number of additional targets \| target									2
Biogen License Agreement \| Research and development services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized that was included in the contract liability at the beginning of the period									$ 55,000,000
Transaction price allocated to performance obligation							$ 3,700,000		3,700,000
Biogen License Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targeted protein degradation \| protein				5
Biogen License Agreement \| Maximum \| Research and development milestones
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment received				$ 35,000,000
Biogen License Agreement \| Maximum \| One-time sales-based payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment received				$ 26,000,000
Calico License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment											$ 5,000,000
Research term						5 years
Amount payable for extend research term option		$ 1,000,000
Research extend term		1 year
Annual payments											$ 5,000,000
Calico License Agreement \| Research and development services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized that was included in the contract liability at the beginning of the period									13,000,000
Calico License Agreement \| Maximum \| One-time sales-based payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment received						$ 65,000,000
Calico License Agreement \| Maximum \| Potential research, development and commercial milestone payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment received						$ 132,000,000
Restated Roche Agreement And Biogen License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Transaction price allocated to performance obligation							$ 33,100,000		$ 33,100,000

Property and equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Property and equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and equipment	$ 15,192		$ 15,192		$ 15,523
Less: accumulated depreciation	(7,902)		(7,902)		(8,123)
Total property and equipment, net	7,290		7,290		7,400
Depreciation and amortization expense	447	$ 415	1,450	$ 1,155
Laboratory equipment
Property Plant And Equipment [Line Items]
Property and equipment	8,303		8,303		8,757
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment	4,766		4,766		4,682
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment	1,181		1,181		1,181
Construction in progress
Property Plant And Equipment [Line Items]
Property and equipment	223		223		183
Office equipment
Property Plant And Equipment [Line Items]
Property and equipment	621		621		529
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment	$ 98		$ 98		$ 191

Stock-based compensation - Summary of RSU activity (Details) - Time-based RSUs	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Shares
Outstanding, beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	824,600
Vested (in shares) \| shares	0
Forfeited (in shares) \| shares	(68,640)
Outstanding, ending balance (in shares) \| shares	755,960
Weighted-Average Grant Date Fair Value
Outstanding, beginning balance (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	5.37
Vested (in dollars per share) \| $ / shares	0
Forfeited (in dollars per share) \| $ / shares	5.67
Outstanding, ending balance (in dollars per share) \| $ / shares	$ 5.35