0000950170-23-021262 | 10-Q | XBRL Viewer

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2023

The following table summarizes the stock plan activity:


	Stock Options Outstanding			Weighted-Average Exercise Price
Outstanding - January 1, 2023		3,316,671		$	2.20
Assumption of options in connection with the Merger		449,900			28.40
Options granted		199,860			25.28
Options exercised and vested		(76,165	)		2.79
Options cancelled and forfeited		—			—
Outstanding - March 31, 2023		3,890,266		$	7.58

Summary of Restricted Stock Activity

The following summarizes restricted stock activity:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested - January 1, 2023		50,457		$	0.14
Granted		—			—
Vested		(11,867	)		0.14
Forfeited		—			—
Unvested - March 31, 2023		38,590		$	0.14

Summary of Stock-Based Compensation Expense

The allocation of stock-based compensation expense was as follows (in thousands):


	Three Months Ended March 31,
	2023		2022
Research and development		492		349
General and administrative		1,770		305
Total stock-based compensation expense	$	2,262	$	654

Summary of Stock-Based Compensation Fair Value Assumptions

The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes model. The following summarizes the inputs used:


	Three Months Ended March 31,
	2023		2022
Stock Price	$25.28		$6.78
Expected term (years)	5.8		6.0 - 6.3
Expected volatility	83%		80%
Risk-free interest rate	4.1%		1.6% - 2.0%
Expected dividend yield		—		—

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Preferred Stock Convertible Preferred Stock	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED DEFICIT
Beginning balance at Dec. 31, 2021	$ (42,887)	$ 149,749	$ 1	$ 2,314	$ (45,202)
Beginning balance, shares at Dec. 31, 2021		61,730,064	3,435,014
Exercise of common stock options	228			228
Exercise of common stock options, shares			122,475
Vesting of restricted stock and stock options	64			64
Stock-based compensation	654			654
Net loss	(8,669)				(8,669)
Ending balance at Mar. 31, 2022	(50,610)	$ 149,749	$ 1	3,260	(53,871)
Ending balance, shares at Mar. 31, 2022		61,730,064	3,557,489
Beginning balance at Dec. 31, 2022	(76,825)	$ 149,749	$ 1	6,038	(82,864)
Beginning balance, shares at Dec. 31, 2022		61,730,064	3,570,019
Exercise of common stock options	140			140
Exercise of common stock options, shares			55,599
Vesting of restricted stock and stock options	73			73
Conversion of convertible preferred stock to common stock	149,749	$ (149,749)	$ 18	149,731
Conversion of convertible preferred stock to common stock, shares		(61,730,064)	18,216,847
Issuance of common stock in the Financing Transaction, net of issuance costs	159,544		$ 13	159,531
Issuance of common stock in the Financing Transaction, net of issuance costs, shares			12,638,636
Issuance of common stock to former stockholders of Imara Inc. in connection with the Merger	80,241		$ 7	80,234
Issuance of common stock to former stockholders of Imara Inc. in connection with the Merger, shares			6,625,176
Adjustment for change in common stock par value in connection with the Merger			$ 2	(2)
Reverse recapitalization transaction costs	(9,044)			(9,044)
Stock-based compensation	2,262			2,262
Net loss	(14,724)				(14,724)
Ending balance at Mar. 31, 2023	$ 291,416		$ 41	$ 388,963	$ (97,588)
Ending balance, shares at Mar. 31, 2023			41,106,277

Preferred Stock and Convertible Preferred Stock - Schedule of Convertible Preferred Stock and Liquidation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Mar. 31, 2023
Class of Stock [Line Items]
Preferred stock, shares authorized	0	10,000,000
Series Seed Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	14,507,038
Shares Issued and Outstanding	14,507,038
Per Share Liquidation Preference	$ 0.71
Preferred stock, liquidation preference, value	$ 10,300
Issuance of convertible preferred stock, net of issuance costs	$ 10,211
Series A Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	25,114,089
Shares Issued and Outstanding	25,114,089
Per Share Liquidation Preference	$ 1.80
Preferred stock, liquidation preference, value	$ 45,300
Issuance of convertible preferred stock, net of issuance costs	$ 45,170
Series B Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	22,108,937
Shares Issued and Outstanding	22,108,937
Per Share Liquidation Preference	$ 3.84
Preferred stock, liquidation preference, value	$ 84,920
Issuance of convertible preferred stock, net of issuance costs	$ 84,689
Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	61,730,064	0
Shares Issued and Outstanding	61,730,064
Preferred stock, liquidation preference, value	$ 140,520	$ 0
Issuance of convertible preferred stock, net of issuance costs	$ 140,070

The Merger (Tables)

3 Months Ended

Mar. 31, 2023

Business Combination And Asset Acquisition [Abstract]

Schedule Of Recapitalization the Company Obtained the Assets and Liabilities

As part of the recapitalization, the Company obtained the assets and liabilities listed below (in thousands):


Cash and cash equivalents	$	81,821
Other current assets		1,044
Accrued liabilities		(2,624	)
Net assets acquired	$	80,241

Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of Financial Assets Measured at Fair Value on a Recurring Basis

The following tables set forth the fair value of the Company’s financial assets measured at fair value on a recurring basis and indicates the level within the fair value hierarchy utilized to determine such values (in thousands):


	As of March 31, 2023
	Total		Level 1		Level 2		Level 3
Assets:
U.S. Treasury backed money market funds	$	290,833	$	290,833	$	—	$	—
Total financial assets measured at fair value	$	290,833	$	290,833	$	—	$	—

	As of December 31, 2022
	Total		Level 1		Level 2		Level 3
Assets:
U.S. Treasury backed money market funds	$	74,523	$	74,523	$	—	$	—
Total financial assets measured at fair value	$	74,523	$	74,523	$	—	$	—

Organization, Description of Business and Liquidity - Additional Information (Details)		3 Months Ended
	Feb. 23, 2023 USD ($) Director shares	Mar. 31, 2023 USD ($) shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) shares
Organization, Description of Business and Liquidity [Line Items]
Entity incorporation date		Jun. 12, 2019
Reverse stock split	1-for-4
Business acquisition, exchange ratio	0.2951%
Common stock, shares issued \| shares	41,011,501	41,106,277		3,570,019
Common stock, shares outstanding \| shares	41,011,501	41,106,277		3,570,019
Majority number of initial members of board of directors \| Director	8
Common stock, par value $0.001 and $0.0001 at March 31, 2023 and December 31, 2022, respectively; authorized shares - 100,000,000 and 26,264,364 at March 31, 2023 and December 31, 2022, respectively; issued and outstanding shares - 41,106,277 and 3,570,019 at March 31, 2023 and December 31, 2022, respectively	$ 164,500,000	$ 41,000		$ 1,000
Accumulated deficit		(97,588,000)		(82,864,000)
Net loss		(14,724,000)	$ (8,669,000)
Contingent value right	one
Payments received under CVR Agreement		0
Cash and cash equivalents		$ 292,102,000	$ 99,878,000	$ 75,536,000
Merger Agreement
Organization, Description of Business and Liquidity [Line Items]
Business acquisition, common shares issued \| shares	34,426,351

Fair Value of Financial Instruments - Schedule of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets:
Total financial assets measured at fair value	$ 290,833	$ 74,523
U.S. Treasury Backed Money Market Funds
Assets:
Total financial assets measured at fair value	290,833	74,523
Level 1
Assets:
Total financial assets measured at fair value	290,833	74,523
Level 1 \| U.S. Treasury Backed Money Market Funds
Assets:
Total financial assets measured at fair value	$ 290,833	$ 74,523

The Merger - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
	Feb. 23, 2023	Mar. 31, 2023	Mar. 31, 2022
Business Acquisition [Line Items]
Stock-based compensation expense		$ 2,262	$ 654
General and Administrative Expense
Business Acquisition [Line Items]
Stock-based compensation expense upon acceleration	$ 1,300
Additional paid-in capital
Business Acquisition [Line Items]
Transaction costs		$ 9,000

Accrued Expenses and Other Current Liabilities (Tables)

3 Months Ended

Mar. 31, 2023

Payables And Accruals [Abstract]

Summary Of Accrued Expenses And Other Current Liabilities

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


	As of March 31, 2023		As of December 31, 2022
Accrued employee compensation costs	$	1,038	$	2,130
Accrued research and development costs		2,582		1,918
Accrued deferred offering costs		221		1,190
Lease liability		326		323
Accrued legal and professional fees		367		269
Other		548		447
Accrued expenses and other current liabilities	$	5,082	$	6,277

Stock-Based Compensation - Summary of Stock Plan Activity (Details)	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Compensation Related Costs [Abstract]
Stock Options Outstanding, Beginning Balance \| shares	3,316,671
Stock Options Outstanding, Assumption of options in connection with the Merger \| shares	449,900
Stock Options Outstanding, Options granted \| shares	199,860
Stock Options Outstanding, Options exercised and vested \| shares	(76,165)
Stock Options Outstanding, Ending Balance \| shares	3,890,266
Weighted-Average Exercise Price, Beginning Balance \| $ / shares	$ 2.20
Weighted-Average Exercise Price, Assumption of options in connection with the Merger \| $ / shares	28.40
Weighted-Average Exercise Price, Options granted \| $ / shares	25.28
Weighted-Average Exercise Price, Options exercised and vested \| $ / shares	2.79
Weighted-Average Exercise Price, Ending Balance \| $ / shares	$ 7.58

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Schedule of Basic and Diluted Net Loss Per Common Share

Basic and diluted net loss per common share were calculated as follows (in thousands, except share and per share amounts):


	Three Months Ended March 31,
	2023			2022
Numerator:
Net loss	$	(14,724	)	$	(8,669	)
Denominator:
Weighted-average common shares outstanding		18,738,115			3,519,314
Less: weighted-average unvested common stock issued upon early exercise of common stock options		(149,069	)		(209,515	)
Less: weighted-average unvested restricted shares of common stock		(74,402	)		(433,020	)
Weighted-average shares used to compute net loss per common share, basic and diluted		18,514,644			2,876,779
Net loss per share, basic and diluted	$	(0.80	)	$	(3.01	)

Anti Dilutive Potential Common Shares Excluded From Computation of Diluted Net Loss Per Share

The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect:


	Three Months Ended March 31,
	2023		2022
Convertible preferred stock (as converted)		—		18,216,847
Stock options outstanding		3,890,266		3,095,064
Unvested restricted stock		59,339		346,567
Total		3,949,605		21,658,478

Common Stock - Following Shares of Common Stock Reserved for Future Issuance (Details) - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Feb. 23, 2023
Class Of Stock [Line Items]
Conversion of convertible preferred stock		18,216,847	18,216,847
Issuance of common stock upon exercise of stock options	3,890,266	3,316,671
Options available for grant under stock plans	3,829,005	906,265
Common stock reserved for future issuance	8,122,028	22,439,783
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Common stock reserved for future issuance	402,757

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,294	$ 1,264
Less: accumulated depreciation	(441)	(374)
Property and equipment, net	853	890
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,191	1,191
Property and equipment estimated useful lives	5
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 103	$ 73
Property and equipment estimated useful lives	3

Net Loss Per Share

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

12. Net Loss Per Share

Basic and diluted net loss per common share were calculated as follows (in thousands, except share and per share amounts):


	Three Months Ended March 31,
	2023			2022
Numerator:
Net loss	$	(14,724	)	$	(8,669	)
Denominator:
Weighted-average common shares outstanding		18,738,115			3,519,314
Less: weighted-average unvested common stock issued upon early exercise of common stock options		(149,069	)		(209,515	)
Less: weighted-average unvested restricted shares of common stock		(74,402	)		(433,020	)
Weighted-average shares used to compute net loss per common share, basic and diluted		18,514,644			2,876,779
Net loss per share, basic and diluted	$	(0.80	)	$	(3.01	)

The Company’s potential dilutive securities, which include convertible preferred stock, unvested restricted stock, and common stock options, have been excluded from the computation of diluted net loss per share as the effect would be antidilutive. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect:


	Three Months Ended March 31,
	2023		2022
Convertible preferred stock (as converted)		—		18,216,847
Stock options outstanding		3,890,266		3,095,064
Unvested restricted stock		59,339		346,567
Total		3,949,605		21,658,478

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 292,102,000	$ 75,536,000
Prepaid expenses and other current assets	5,901,000	2,217,000
Total current assets	298,003,000	77,753,000
Property and equipment, net	853,000	890,000
Right-of-use asset	551,000	626,000
Deferred offering costs		3,975,000
Restricted cash	54,000	54,000
Other long-term assets	3,405,000
Total assets	302,866,000	83,298,000
Current liabilities:
Accounts payable	5,860,000	3,438,000
Accrued expenses and other current liabilities	5,082,000	6,277,000
Total current liabilities	10,942,000	9,715,000
Long-term liabilities	508,000	659,000
Total liabilities	11,450,000	10,374,000
Commitments and contingencies (Note 8):
Preferred stock, value
Stockholders' equity (deficit):
Preferred stock, value
Common stock, par value $0.001 and $0.0001 at March 31, 2023 and December 31, 2022, respectively; authorized shares - 100,000,000 and 26,264,364 at March 31, 2023 and December 31, 2022, respectively; issued and outstanding shares - 41,106,277 and 3,570,019 at March 31, 2023 and December 31, 2022, respectively	41,000	1,000
Additional paid-in capital	388,963,000	6,038,000
Accumulated deficit	(97,588,000)	(82,864,000)
Total stockholders' equity (deficit)	291,416,000	(76,825,000)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	$ 302,866,000	83,298,000
Convertible Preferred Stock
Current liabilities:
Preferred stock, value		149,749,000
Stockholders' equity (deficit):
Preferred stock, value		$ 149,749,000

Preferred Stock and Convertible Preferred Stock (Tables)

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Schedule of Convertible Preferred Stock and Liquidation

The authorized, issued and outstanding shares of the convertible preferred stock and liquidation preferences of Former Enliven as of December 31, 2022 were as follows (in thousands, except share and per share amounts):


	Authorized Shares		Shares Issued and Outstanding		Per Share Liquidation Preference		Aggregate Liquidation Amount (in thousands)		Proceeds Net of Issuance Costs (in thousands)
Series Seed convertible preferred stock		14,507,038		14,507,038	$	0.71	$	10,300	$	10,211
Series A convertible preferred stock		25,114,089		25,114,089		1.80		45,300		45,170
Series B convertible preferred stock		22,108,937		22,108,937		3.84		84,920		84,689
Total convertible preferred stock		61,730,064		61,730,064			$	140,520	$	140,070

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Statement Of Stockholders Equity [Abstract]
Issuance costs incurred	$ 4,955

The Merger

3 Months Ended

Mar. 31, 2023

Business Combination And Asset Acquisition [Abstract]

The Merger

3. The Merger

As described in Note 1, Former Enliven merged with the Company on February 23, 2023. The Merger was accounted for as a reverse recapitalization with Former Enliven as the accounting acquirer. The primary pre-combination assets of the Company were cash and cash equivalents. Under reverse recapitalization accounting, the assets and liabilities of the Company were recorded at their fair value, which approximated book value due to the short-term nature of the instruments. No goodwill or intangible assets were recognized. Consequently, the unaudited condensed consolidated financial statements of the Company reflect the operations of Former Enliven for accounting purposes together with a deemed issuance of shares, equivalent to the shares held by the former stockholders of the legal acquirer and a recapitalization of the equity of the accounting acquirer.

As part of the recapitalization, the Company obtained the assets and liabilities listed below (in thousands):


Cash and cash equivalents	$	81,821
Other current assets		1,044
Accrued liabilities		(2,624	)
Net assets acquired	$	80,241

The Company incurred $1.3 million in stock-based compensation expense as a result of the acceleration of vesting of stock options at the time of Merger. This amount was recorded in general and administrative expense on the accompanying condensed consolidated statements of operations for the three months ended March 31, 2023. Additionally, the Company incurred transaction costs of $9.0 million, and this amount was recorded as a reduction to additional paid-in capital in the condensed consolidated statements of convertible preferred stock and stockholders’ equity (deficit) for the three months ended March 31, 2023.

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Property Plant And Equipment [Abstract]
Depreciation expense	$ 67,000	$ 39,000

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2023	May 01, 2023
Cover [Abstract]
Entity Registrant Name	ENLIVEN THERAPEUTICS, INC.
Document Type	10-Q
Trading Symbol	ELVN
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		41,114,795
Amendment Flag	false
Entity Central Index Key	0001672619
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Mar. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NASDAQ
Entity File Number	001-39247
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-1523849
Entity Address, Address Line One	6200 Lookout Road
Entity Address, City or Town	Boulder
Entity Address, State or Province	CO
Entity Address, Postal Zip Code	80301
City Area Code	720
Local Phone Number	647-8519
Document Quarterly Report	true
Document Transition Report	false

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated share based compensation expense	$ 2,262	$ 654
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated share based compensation expense	492	349
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated share based compensation expense	$ 1,770	$ 305

Common Stock

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Common Stock

9. Common Stock

Upon completion of the Merger on February 23, 2023, the Company issued an aggregate of 34,426,351 shares of its common stock to Former Enliven stockholders, based on an exchange ratio of approximately 0.2951 share of the Company’s common stock for each share of Former Enliven common stock outstanding immediately prior to the Merger, including those shares of common stock issued upon conversion of the Former Enliven preferred stock (18,216,847 common shares) and those shares issued with its pre-merger financing of $164.5 million (12,638,636 common shares).

As of March 31, 2023, the Company’s Amended and Restated Certificate of Incorporation authorized the Company to issue 100,000,000 shares of $0.001 par value common stock, of which 41,106,277 shares were issued and outstanding, respectively. As of March 31, 2023 and December 31, 2022, there were 199,478 and 252,662 shares subject to repurchase, respectively. The liability related to shares subject to repurchase totaled $0.6 million and $0.6 million as of March 31, 2023 and December 31, 2022, respectively, of which $0.3 million and $0.3 million were recorded as long-term liabilities as of March 31, 2023 and December 31, 2022, respectively.

Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the Company’s board of directors, if any. No dividends have been declared or paid by the Company through March 31, 2023.

The Company had the following shares of common stock reserved for future issuance as of March 31, 2023 and December 31, 2022:


	As of March 31, 2023		As of December 31, 2022
Conversion of convertible preferred stock		—		18,216,847
Issuance of common stock upon exercise of stock options		3,890,266		3,316,671
Options available for grant under stock plans		3,829,005		906,265
Shares available for issuance under the Employee Stock Purchase Plan		402,757		—
Total common stock reserved for future issuance		8,122,028		22,439,783

- Definition

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

+ References

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

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

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

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

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

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

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

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

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

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

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

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

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

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

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

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

+ Details

Preferred Stock and Convertible Preferred Stock

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Preferred Stock and Convertible Preferred Stock

10. Preferred Stock and Convertible Preferred Stock

Preferred Stock

As of March 31, 2023, the Company was authorized to issue up to 10,000,000 shares of preferred stock at a par value of $0.001. As of March 31, 2023, no shares of preferred stock were issued and outstanding.

Convertible Preferred Stock

On February 23, 2023, Former Enliven completed the Merger with the Company in accordance with the Merger Agreement. Under the terms of the Merger Agreement, immediately prior to the effective time of the Merger, each share of Former Enliven’s preferred stock was converted into a share of Former Enliven’s common stock. At closing of the merger, the Company issued an aggregate of 34,426,351 shares of its common stock to Former Enliven stockholders, based on an exchange ratio of approximately 0.2951 shares of the Company’s common stock for each share of Former Enliven’s common stock outstanding immediately prior to the Merger, including those shares of common stock issued upon conversion of the Former Enliven preferred stock. No shares of convertible preferred stock were issued during the year ended December 31, 2022 or three months ended March 31, 2023.


	Authorized Shares		Shares Issued and Outstanding		Per Share Liquidation Preference		Aggregate Liquidation Amount (in thousands)		Proceeds Net of Issuance Costs (in thousands)
Series Seed convertible preferred stock		14,507,038		14,507,038	$	0.71	$	10,300	$	10,211
Series A convertible preferred stock		25,114,089		25,114,089		1.80		45,300		45,170
Series B convertible preferred stock		22,108,937		22,108,937		3.84		84,920		84,689
Total convertible preferred stock		61,730,064		61,730,064			$	140,520	$	140,070

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2023	Feb. 23, 2023	Dec. 31, 2022
Preferred stock, par value	$ 0.001		$ 0.001
Preferred stock, shares authorized	10,000,000		0
Preferred stock, shares issued	0		0
Preferred stock, shares outstanding	0		0
Common stock, par value	$ 0.001		$ 0.0001
Common stock, shares authorized	100,000,000		26,264,364
Common stock, shares issued	41,106,277	41,011,501	3,570,019
Common stock, shares outstanding	41,106,277	41,011,501	3,570,019
Convertible Preferred Stock
Preferred stock, par value	$ 0.0001		$ 0.0001
Preferred stock, shares authorized	0		61,730,064
Preferred stock, shares issued	0		61,730,064
Preferred stock, shares outstanding	0		61,730,064
Preferred stock, liquidation preference, value	$ 0		$ 140,520

Leases

3 Months Ended

Mar. 31, 2023

Leases [Abstract]

Leases

5. Leases

Facility lease

In June 2020, the Company executed a sublease agreement for 6,782 square feet of office and laboratory space, which was set to expire on December 30, 2021. In March 2021, the Company amended its sublease agreement, increasing the leased space by 2,495 square feet to 9,277 square feet and monthly rent to $12,000. In April 2022, the lease term was extended to December 30, 2024. In addition, the Company’s lease space was increased to 18,170 square feet commencing in July 2022, and the rental payments were increased by an equally proportionate amount to reflect the increase in floor space. The monthly rent is subject to annual increases through the lease term. The Company is required to pay base rent expense as well as its proportionate share of the facilities operating expenses. The non-lease components, consisting primarily of common area maintenance, are paid separately based on actual costs incurred. Therefore, the variable non-lease components were not included in the ROU asset and lease liability and are reflected as expense in the period incurred. The incremental borrowing rate used to calculate the Company’s ROU assets and lease liabilities is 4%. The incremental borrowing rate was estimated based on the Company estimated borrowing rate on a collateralized loan. As of March 31, 2023, the remaining lease liability and ROU asset were $0.6 million and $0.6 million, respectively. As of December 31, 2022, the remaining lease liability and ROU asset were $0.6 million and $0.6 million, respectively.

The Company recognized rent expense under the facility sublease for the three months ended March 31, 2023 and 2022 of $81,000 and $41,000, respectively. As of March 31, 2023, the future minimum lease payments under the facilities operating sublease were as follows (in thousands):


	As of March 31, 2023
Year ending December 31,
2023 (remaining nine months)	$	247
2024		341
Thereafter		—
Total minimum lease payments		588
Less: amount representing interest		(20	)
Present value of lease liabilities		568
Less: current portion of lease liabilities		(326	)
Lease liabilities, non-current	$	242

Commitments and Contingencies

3 Months Ended

Mar. 31, 2023

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

8. Commitments and Contingencies

Lease commitments

The Company’s commitments related to lease agreements are disclosed in Note 5.

Litigation

From time to time, the Company may be involved in legal proceedings or be subject to claims arising in the ordinary course of its business. The Company was not currently a party to any legal proceedings. Regardless of outcome, any proceedings or claims can have an adverse impact on the Company because of defense and settlement costs, diversion of resources and other factors, and there can be no assurances that favorable outcomes will be obtained.

Following the filing of the preliminary proxy statement/registration statement in connection with the Company’s stockholder meeting to consider the merger between the Company (then-named Imara Inc.) and Former Enliven, the Company and its board of directors were named in a shareholder complaint captioned Juerling v. Imara Inc., et al., 1:22-cv-09986 (S.D.N.Y. filed November 23, 2022) (the “Complaint”) and also received demand letters from certain stockholders (collectively, the “Demands” and with the Complaint, the “Actions”).

The Complaint generally alleged violations of Sections 14(a) and 20(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), in connection with the filing of the preliminary proxy statement/registration statement. In particular, the Complaint generally alleged that the registration statement contained materially misleading and incomplete information concerning, among other things: (i) certain conflicts of interest involving the Company and its board of directors; (ii) the background and sales process leading up to the Merger Agreement; (iii) the Company’s and Former Enliven’s financial projections; and (iv) the data and inputs underlying the financial analyses performed by SVB Securities, which acted as the Company’s financial advisor for the Merger. As relief, the complaint sought (i) an injunction of the proposed Merger; (ii) recission in the event the Merger is consummated or, alternatively, rescissory damages; (iii) an injunction requiring the individual defendants to file a new registration statement that is not false or misleading; (iv) an award of costs, including attorneys’ and experts’ fees; and (v) any further relief that the court deems just and proper.

Following discussions between the Company and counsel in the Actions, on December 19, 2022 and February 13, 2023, the Company filed a Form S-4/A and Form 8-K, respectively, with the Securities and Exchange Commission that contained additional information that mooted the disclosure claims asserted in the Actions (the “Supplemental Disclosures”). In connection with the filing of the Supplemental Disclosures, counsel in the Actions informed Defendants that, in light of the mootness of the stockholders’ claims, that stockholders would voluntarily dismiss the Complaint by filing a notice of voluntary dismissal, and agreed to not further pursue the actions contemplated by the Demands. On January 19, 2023, the Complaint was voluntarily dismissed by plaintiff.

The Company subsequently agreed to pay a mootness fee of an immaterial amount.

Indemnification agreements

In the ordinary course of business, the Company has provided and may provide indemnification of varying scope and terms to vendors, consultants, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations in its condensed consolidated financial statements as of March 31, 2023 or December 31, 2022.

Stock-Based Compensation - Additional Information (Details)				1 Months Ended				3 Months Ended		12 Months Ended	19 Months Ended
	Feb. 23, 2023 shares	Aug. 09, 2022 USD ($) $ / shares shares	Mar. 11, 2020 shares	Aug. 31, 2022 shares	Dec. 31, 2020 shares	Apr. 30, 2020 shares	Jun. 30, 2019 $ / shares shares	Mar. 31, 2023 USD ($) shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 shares	Dec. 31, 2020 USD ($) shares	Jul. 31, 2019 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance								8,122,028		22,439,783
Reverse stock split	1-for-4
Stock-based compensation expense \| $								$ 2,262,000	$ 654,000
Stock issued during period, value, new issues \| $								159,544,000
Shares issued	34,426,351
Allocated share based compensation expense \| $								2,262,000	654,000
Incremental stock-based compensation expense \| $								2,262,000	654,000
Total compensation cost not yet recognized related to unvested stock options \| $								$ 11,100,000
Expected to be recognized over a weighted-average period								2 years 4 months 24 days
General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated share based compensation expense \| $								$ 1,770,000	305,000
Incremental stock-based compensation expense \| $								$ 1,770,000	$ 305,000
Stock Option Repricing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated share based compensation expense \| $		$ 1,000,000.0
Minimum exercise price for repriced options \| $ / shares		$ 4.68
Maximum exercise price for repriced options \| $ / shares		$ 7.56
Repricing vested and unvested stock options outstanding		2,209,826
Incremental stock-based compensation expense \| $		$ 1,000,000.0
Incremental stock compensation expense for option repricing for vested stock options. \| $		300,000
Incremental stock compensation expense for option repricing for unvested stock options \| $		$ 700,000
Remaining weighted-average vesting period		2 years 10 months 24 days
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares subject to repurchase								20,749		41,499
Restricted Stock \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issued shares in restricted common stock to its founders							3,000,000.0
Issued shares in restricted common stock to its founders , per share \| $ / shares							$ 0.0003
Restricted Stock \| Enliven Inc. \| Vested Upon Issuance
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vested immediately upon issuance							25.00%
Restricted Stock \| Employees and Consultants \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock shares issued											197,262
Restricted stock shares issued value \| $											$ 27,000
Maximum \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period								5 years
Maximum \| Restricted Stock \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining shares vesting period							48 months
Minimum \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period								4 years
Minimum \| Restricted Stock \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining shares vesting period							36 months
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized				4,681,244
Number of additional shares authorized				885,315
Common stock reserved for future issuance												0
2019 Equity Incentive Plan \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized					3,795,929	2,584,138					3,795,929
Number of additional shares authorized					1,211,791	2,210,062
2019 Equity Incentive Plan \| Stock Option Repricing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Excercise price for repriced options \| $ / shares		$ 2.48
2019 Equity Incentive Plan \| Maximum \| Enliven Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized												374,076
2016 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			0
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance								3,829,005
Award expiration period from date of grant	10 years
Award vesting period	4 years
Reverse stock split	1-to-4
Reverse stock split conversion ratio	0.25
Number of shares of common stock that may be issued accordance with plan	4,275,000
Description of changes in the number of shares reserved for issuance								The number of shares reserved shall be annually increased on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2024 and continuing until, and including, the fiscal year commencing January 1, 2032, equal to the least of (i) 4.5% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (ii) an amount determined by the Company’s board of directors.
Common stock outstanding percent	4.50%
2020 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance								402,757
Exercise price per share of stock options as percentage of fair market value of common stock			85.00%
Reverse stock split conversion ratio	0.25
Number of shares of common stock that may be issued accordance with plan	407,133
Common stock outstanding percent	1.00%

Net Loss Per Share - Anti Dilutive Potential Common Shares Excluded From Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share Basic [Line Items]
Convertible preferred stock (as converted)	3,949,605	21,658,478
Convertible Preferred Stock (as converted)
Earnings Per Share Basic [Line Items]
Convertible preferred stock (as converted)		18,216,847
Stock Options Outstanding
Earnings Per Share Basic [Line Items]
Convertible preferred stock (as converted)	3,890,266	3,095,064
Unvested Restricted Stock
Earnings Per Share Basic [Line Items]
Convertible preferred stock (as converted)	59,339	346,567

Leases - Summary of Future Minimum Lease Payments Under Operating Sublease (Details) $ in Thousands	Mar. 31, 2023 USD ($)
Leases [Abstract]
2023 (remaining nine months)	$ 247
2024	341
Total minimum lease payments	588
Less: amount representing interest	(20)
Present value of lease liabilities	568
Less: current portion of lease liabilities	(326)
Lease liabilities, non-current	$ 242

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (14,724)	$ (8,669)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	67	39
Stock-based compensation	2,262	654
Changes in operating assets and liabilities:
Prepaid expenses, other current and long-term assets	(6,088)	(542)
Right-of-use asset	(1)
Accounts payable	492	(1,557)
Accrued expenses and other liabilities	(2,852)	(286)
Net cash used in operating activities	(20,844)	(10,361)
Cash flows from investing activities:
Purchases of property and equipment	(31)	(194)
Net cash used in investing activities	(31)	(194)
Cash flows from financing activities:
Proceeds from exercise of stock options	140	573
Deferred offering costs related to initial public offering		(164)
Proceeds from the Financing Transaction, net of issuance costs	162,900
Cash acquired in connection with the reverse recapitalization	81,821
Payment of reverse recapitalization transaction costs	(7,420)
Net cash provided by financing activities	237,441	409
Net increase (decrease) in cash, cash equivalents and restricted cash	216,566	(10,146)
Cash, cash equivalents and restricted cash at the beginning of the period	75,590	110,078
Cash, cash equivalents and restricted cash at the end of the period	292,156	99,932
Components of cash, cash equivalents and restricted cash:
Cash and cash equivalents	292,102	99,878
Restricted cash	54	54
Total cash, cash equivalents and restricted cash	292,156	99,932
Supplemental disclosure of non-cash operating activities:
Issuance costs related to the Financing Transaction included in accounts payable	1,534
Transaction costs related to reverse recapitalization included in accounts payable and accrued expenses and other current liabilities	1,316
Issuance costs related to the initial public offering included in accrued expenses and other current liabilities		$ 98
Supplemental disclosure of non-cash investing and financing activities:
Conversion of convertible preferred stock to common stock	$ 149,749

Common Stock - Additional Information (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 23, 2023 USD ($) shares	Mar. 31, 2023 USD ($) Vote $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares
Class of Stock [Line Items]
Shares issued	34,426,351
Business acquisition, exchange ratio	0.2951%
Shares issued upon conversion of preferred stock	18,216,847		18,216,847
Pre-merger financing amount \| $	$ 164,500
Pre-merger financing shares issued	12,638,636
Common stock, shares authorized		100,000,000	26,264,364
Common stock, par value \| $ / shares		$ 0.001	$ 0.0001
Common stock, shares issued	41,011,501	41,106,277	3,570,019
Common stock, shares outstanding	41,011,501	41,106,277	3,570,019
Shares subject to repurchase		199,478	252,662
Liability related to shares subject to repurchase \| $		$ 600	$ 600
Number of vote by common stock holders \| Vote		1
Long-term liabilities
Class of Stock [Line Items]
Liability related to shares subject to repurchase \| $		$ 300	$ 300
Dividend Declared
Class of Stock [Line Items]
Dividends \| $		0
Dividend Paid
Class of Stock [Line Items]
Dividends \| $		$ 0

Accrued Expenses and Other Current Liabilities

3 Months Ended

Mar. 31, 2023

Payables And Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

7. Accrued Expenses and Other Current Liabilities

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


	As of March 31, 2023		As of December 31, 2022
Accrued employee compensation costs	$	1,038	$	2,130
Accrued research and development costs		2,582		1,918
Accrued deferred offering costs		221		1,190
Lease liability		326		323
Accrued legal and professional fees		367		269
Other		548		447
Accrued expenses and other current liabilities	$	5,082	$	6,277

Common Stock (Tables)

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Following Shares of Common Stock Reserved for Future Issuance

The Company had the following shares of common stock reserved for future issuance as of March 31, 2023 and December 31, 2022:


	As of March 31, 2023		As of December 31, 2022
Conversion of convertible preferred stock		—		18,216,847
Issuance of common stock upon exercise of stock options		3,890,266		3,316,671
Options available for grant under stock plans		3,829,005		906,265
Shares available for issuance under the Employee Stock Purchase Plan		402,757		—
Total common stock reserved for future issuance		8,122,028		22,439,783

Stock-Based Compensation - Summary of Stock-Based Compensation Fair Value Assumptions (Details) - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Price	$ 25.28	$ 6.78
Expected term (years)	5 years 9 months 18 days
Expected volatility	83.00%	80.00%
Risk-free interest rate	4.10%
Risk-free interest rate, minimum		1.60%
Risk-free interest rate, maximum		2.00%
Minimum \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)		6 years
Maximum \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)		6 years 3 months 18 days

Accrued Expenses and Other Current Liabilities - Summary Of Accrued Expenses And Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Payables And Accruals [Abstract]
Accrued employee compensation costs	$ 1,038	$ 2,130
Accrued research and development costs	2,582	1,918
Accrued deferred offering costs	221	1,190
Lease liability	326	323
Accrued legal and professional fees	367	269
Other	548	447
Accrued expenses and other current liabilities	$ 5,082	$ 6,277

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating expenses:
Research and development	$ 11,880	$ 7,059
General and administrative	4,538	1,619
Total operating expenses	16,418	8,678
Loss from operations	(16,418)	(8,678)
Other income (expense), net
Interest income	1,694	9
Total other income (expense), net	1,694	9
Net loss and comprehensive loss	$ (14,724)	$ (8,669)
Net loss per share, basic	$ (0.80)	$ (3.01)
Net loss per share, diluted	$ (0.80)	$ (3.01)
Weighted-average shares outstanding, basic	18,514,644	2,876,779
Weighted-average shares outstanding, diluted	18,514,644	2,876,779

Leases (Tables)

3 Months Ended

Mar. 31, 2023

Leases [Abstract]

Summary of Future Minimum Lease Payments Under Operating Sublease

As of March 31, 2023, the future minimum lease payments under the facilities operating sublease were as follows (in thousands):


	As of March 31, 2023
Year ending December 31,
2023 (remaining nine months)	$	247
2024		341
Thereafter		—
Total minimum lease payments		588
Less: amount representing interest		(20	)
Present value of lease liabilities		568
Less: current portion of lease liabilities		(326	)
Lease liabilities, non-current	$	242

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Numerator:
Net loss	$ (14,724)	$ (8,669)
Denominator:
Weighted-Average Common Shares Outstanding	18,738,115	3,519,314
Less: weighted-average unvested common stock issued upon early exercise of common stock options	(149,069)	(209,515)
Less: weighted-average unvested restricted shares of common stock	74,402	433,020
Weighted-average shares outstanding, basic	18,514,644	2,876,779
Weighted-average shares outstanding, diluted	18,514,644	2,876,779
Net loss per share, basic	$ (0.80)	$ (3.01)
Net loss per share, diluted	$ (0.80)	$ (3.01)

Fair Value of Financial Instruments

3 Months Ended

Mar. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

4. Fair Value of Financial Instruments


	As of March 31, 2023
	Total		Level 1		Level 2		Level 3
Assets:
U.S. Treasury backed money market funds	$	290,833	$	290,833	$	—	$	—
Total financial assets measured at fair value	$	290,833	$	290,833	$	—	$	—

	As of December 31, 2022
	Total		Level 1		Level 2		Level 3
Assets:
U.S. Treasury backed money market funds	$	74,523	$	74,523	$	—	$	—
Total financial assets measured at fair value	$	74,523	$	74,523	$	—	$	—

Money market funds are highly liquid investments that are valued based on quoted market prices in active markets, which represent a Level 1 measurement within the fair value hierarchy.

- 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

Subsequent Events

3 Months Ended

Mar. 31, 2023

Subsequent Events [Abstract]

Subsequent Events

13. Subsequent Events

The Company evaluated subsequent events from March 31, 2023, the date of these unaudited condensed consolidated financial statements, through May 11, 2023, which represents the date the unaudited condensed consolidated financial statements were issued, for events requiring recording or disclosure in the unaudited condensed consolidated financial statements for the three months ended March 31, 2023. The Company concluded that no events have occurred that would require recognition or disclosure in the unaudited condensed consolidated financial statements.

Property and Equipment, Net

3 Months Ended

Mar. 31, 2023

Property Plant And Equipment [Abstract]

Property and Equipment, Net

6. Property and Equipment, Net

Property and equipment, net consisted of the following (dollar amounts in thousands):


	Estimated Useful Life in Years	As of March 31, 2023			As of December 31, 2022
Laboratory equipment	5	$	1,191		$	1,191
Computer equipment	3		103			73
Property and equipment, gross			1,294			1,264
Less: accumulated depreciation			(441	)		(374	)
Property and equipment, net		$	853		$	890

Depreciation expense for the three months ended March 31, 2023 and 2022 was $67,000 and $39,000, respectively.

The Merger - Schedule of Recapitalization the Company obtained the Assets and Liabilities (Details) $ in Thousands	Feb. 23, 2023 USD ($)
Business Combination And Asset Acquisition [Abstract]
Cash and cash equivalents	$ 81,821
Other current assets	1,044
Accrued liabilities	(2,624)
Net assets acquired	$ 80,241

Organization, Description of Business and Liquidity

3 Months Ended

Mar. 31, 2023

Organization Description Of Business And Liquidity [Abstract]

Organization Description of Business and Liquidity

1. Organization, Description of Business and Liquidity

Business

Enliven Inc. (formerly, Enliven Therapeutics, Inc.) (“Former Enliven”) was incorporated in the State of Delaware on June 12, 2019. Enliven Therapeutics, Inc. (formerly Imara Inc.) (the “Company”) is headquartered in Boulder, Colorado. The Company is a clinical-stage biopharmaceutical company focused on the discovery and development of small molecule inhibitors to help patients with cancer not only live longer, but better. The Company aims to address existing and emerging unmet needs with a precision oncology approach that improves survival and enhances overall patient well-being. Its discovery process combines deep insights in clinically validated biological targets and differentiated chemistry with the goal of designing therapies for unmet needs.

Since its inception, the Company has devoted substantially all of its efforts to research and development activities, business planning, establishing and maintaining its intellectual property portfolio, hiring personnel, raising capital, and providing general and administrative support for these activities. To date, the Company has funded its operations primarily through private placements of its common and convertible preferred stock.

The Merger and Financing Transaction

On October 13, 2022, the Company entered into an agreement and plan of merger (“Merger Agreement” and such transactions considered by the Merger Agreement, the “Merger”) with Former Enliven.

On February 23, 2023, the Company completed the Merger with Former Enliven in accordance with the Merger Agreement. Prior to the effective time of the Merger, the Company effected a 1-for-4 reverse stock split (the “Reverse Stock Split”), and right after the Merger, the Company changed its name to Enliven Therapeutics, Inc. Subject to the terms and conditions of the Merger Agreement, at the closing of the Merger, (a) each outstanding share of Former Enliven common stock (including common stock issued upon the conversion of its preferred stock) was converted into the right to receive a number of shares of the Company’s common stock (“Company Common Stock”) (after giving effect to the Reverse Stock Split) equal to the exchange ratio per the Merger Agreement; and (b) each then outstanding Former Enliven stock option that had not previously been exercised prior to the closing of the Merger was assumed by the Company. At closing of the Merger, the Company issued an aggregate of 34,426,351 shares of Company Common Stock to Former Enliven’s stockholders, based on an exchange ratio of approximately 0.2951 shares of Company Common Stock for each share of Former Enliven common stock outstanding immediately prior to the Merger, including those shares of common stock issued upon conversion of the Former Enliven preferred stock, resulting in 41,011,501 shares of Company Common Stock being issued and outstanding immediately following the effective time of the Merger. The Company also assumed all of the outstanding and unexercised stock options to purchase shares of Former Enliven common stock. The assumed options continue to be governed by the terms of the 2019 Equity Incentive Plan (as discussed more in Note 11) under which the options were originally granted, with such options hence forth representing the right to purchase a number of shares of Company Common Stock equal to approximately 0.2951 multiplied by the number of shares of Former Enliven common stock previously represented by such options.

The Merger was accounted for as a reverse recapitalization in accordance with generally accepted accounting principles in the United States of America ("U.S. GAAP"). Under this method of accounting, Former Enliven was deemed to be the accounting acquirer for financial reporting purposes. This determination was primarily based on the expectation that, immediately following the Merger: (i) Former Enliven stockholders will own a substantial majority of the voting rights; (ii) Former Enliven will designate a majority (eight of nine) of the initial members of the board of directors of the combined company; and (iii) Former Enliven’s executive management team will become the management team of the combined company; and (iv) the combined company will be named Enliven Therapeutics, Inc. and be headquartered in Boulder, Colorado. Accordingly, for accounting purposes, the Merger was treated as the equivalent of Former Enliven issuing stock to acquire the net assets of the Company. As a result of the Merger, the net assets of the Company were recorded at their acquisition-date fair value in the financial statements of Former Enliven and the reported operating results prior to the Merger will be those of Former Enliven. Historical common share figures of Former Enliven have been retroactively restated based on the exchange ratio of approximately 0.2951.

On February 23, 2023, prior to the effective time of the Merger, the Company entered into a Contingent Value Rights Agreement (the “CVR Agreement”) with a rights agent, pursuant to which the Company’s pre-Merger common stockholders received one contingent value right (each, a “CVR”) for each outstanding share of the Company’s common stock held by such stockholder as of February 22, 2023. Each CVR represents the contractual right to receive payments upon the occurrence of certain events related to

the Company’s sale of certain assets prior to the completion of the Merger, in each case subject to, and in accordance with, the terms and conditions of the CVR Agreement. As of March 31, 2023, no payments have been received under the CVR Agreement.

Concurrently with the execution of the Merger Agreement, and in order to provide Former Enliven with additional capital for its development programs prior to the closing of the Merger, certain new and current investors purchased an aggregate of $164.5 million of common stock of Former Enliven (the “Financing Transaction”).

Risks and uncertainties

The Company is subject to risks common to development-stage companies in the biotechnology industry including, but not limited to, risks of failure of preclinical studies and clinical trials, new technological innovations, protection of proprietary technology, dependence on key personnel, reliance on third-party organizations, risks of obtaining regulatory approval for any product candidate that it may develop, compliance with government regulations and the need to obtain additional financing.

The Company continues to closely monitor macroeconomic and geopolitical developments, including inflation, instability in the banking and financial services sector, tightening of the credit markets, the raising of the debt ceiling, the Russia-Ukraine conflict and COVID-19. The extent of the impact of these developments on the Company’s business, operations and research and development timelines and plans remains uncertain, and will depend on numerous factors, including the impact, if any, on the Company’s personnel, responses of governmental entities, and the responses of third parties such as contract research organizations, contract manufacturing organizations and other third parties with whom the Company does business. Any prolonged material disruption to the Company’s employees or suppliers could adversely impact the Company’s development activities, financial condition and results of operations, including its ability to obtain financing. The Company is monitoring the potential impact of these developments on its business and consolidated financial statements. To date, the Company has not experienced material business disruptions or incurred impairment losses in the carrying values of its assets as a result of these developments, and it is not aware of any specific related event or circumstance that would require it to revise its estimates reflected in these condensed consolidated financial statements.

Liquidity considerations

In order to complete the development of the Company’s product candidates and to build the sales, marketing and distribution infrastructure that the Company believes will be necessary to commercialize its product candidates, if approved, the Company will require substantial additional capital. Until the Company can generate a sufficient amount of revenue from the commercialization of its product candidates, the Company may seek to raise any necessary additional capital through equity or debt financings, loans or other capital sources, which could include income from collaborations, partnerships or other marketing, distribution, licensing or other strategic arrangements with third parties, or from grants. Because of the numerous risks and uncertainties associated with research, development and commercialization of product candidates, the Company is unable to estimate the exact amount and timing of its capital requirements. The Company does not expect to generate any meaningful revenue unless and until the Company obtains regulatory approval of and commercializes any of its product candidates, and the Company does not know when, or if, that will occur.

The Company has incurred significant losses and negative cash flows from operations since inception. As of March 31, 2023, the Company had an accumulated deficit of $97.6 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of $14.7 million and $8.7 million for the three months ended March 31, 2023 and 2022, respectively. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues to develop its product candidates. The Company currently expects that its cash and cash equivalents of $292.1 million as of March 31, 2023 will be sufficient to fund operating expenses and capital requirements for at least 12 months from the date the unaudited condensed consolidated financial statements are issued.

Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended
	Mar. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)
Summary of Significant Accounting Policies [LineItems]
Restricted cash	$ 54,000	$ 54,000
Restricted cash collateral of sublease	54,000
Losses recognized by uninsured balances	0
Deferred offering costs capitalized	$ 0	$ 4,000,000.0
Expected dividend yield	0.00%
Number of operating segments \| Segment	1
Adoption of accounting standards update [true false]	true
Accounting standards update, adoption date	Jan. 01, 2022
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate201912Member
Accounting standards update, immaterial effect [true false]	true
Minimum
Summary of Significant Accounting Policies [LineItems]
Property and equipment estimated useful lives	3 years
Maximum
Summary of Significant Accounting Policies [LineItems]
Property and equipment estimated useful lives	5 years

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of March 31, 2023 and for the three months ended March 31, 2023 and 2022 have been prepared in conformity with U.S. GAAP, for interim financial information and pursuant to Article 10 of Regulation S-X of the Securities Act of 1933, as amended (the "Securities Act"). Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. These unaudited condensed consolidated financial statements have been prepared on the same basis as the Company’s audited financial statements and include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows. The results for the three months ended March 31, 2023 are not necessarily indicative of the results expected for the full fiscal year or any subsequent interim period. The condensed balance sheet as of December 31, 2022 has been derived from the audited financial statements at that date but does not include all disclosures required by U.S. GAAP for complete financial statements. Because all of the disclosures required by U.S. GAAP for complete financial statements are not included herein, these unaudited condensed consolidated financial statements and the notes accompanying them should be read in conjunction with Former Enliven’s audited financial statements as of and for the year ended December 31, 2022. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification ("ASC"), and Accounting Standards Update, ("ASU"), of the Financial Accounting Standards Board ("FASB").
Use of estimates	Use of estimates The preparation of financial statements in accordance 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 at the date of the financial statements, and the reported amounts of income and expense during the reporting period. The most significant estimates relate to the determination of fair value of the Company’s common stock, stock-based compensation and accrued research and development expenses. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, and makes adjustments when facts and circumstances dictate.
Cash and cash equivalents	Cash and cash equivalents The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents are recorded at cost, which approximates fair value. As of March 31, 2023 and December 31, 2022, cash and cash equivalents consisted primarily of checking and money market funds composed of U.S. government obligations.
Restricted cash	Restricted cash The Company classifies all cash whose use is limited by contractual provisions as restricted cash. Restricted cash arises from the requirement for the Company to maintain cash of $54,000 as collateral for a sublease with the facility’s landlord. As of March 31, 2023 and December 31, 2022, $54,000 of restricted cash was reflected in restricted cash in the balance sheets.
Concentrations of credit risk and off-balance sheet risk	Concentrations of credit risk and off-balance sheet risk The Company maintains its cash accounts and money market funds that at times exceed insured limits. As of March 31, 2023 and December 31, 2022, the Company’s cash balances exceeded those that are federally insured. To date, the Company has not recognized any losses caused by uninsured balances.
Fair value measurements	Fair value measurements Financial assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the price the Company would receive to sell an investment in a timely transaction or pay to transfer a liability in a timely transaction with an independent buyer in the principal market, or in the absence of a principal market, the most advantageous market for the investment or liability. A framework is used for measuring fair value utilizing a three-tier hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are as follows: • Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2—Quoted prices in markets that are not considered to be active or financial instrument valuations for which all significant inputs are observable, either directly or indirectly; and • Level 3—Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. Financial instruments are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and considers factors specific to the investment. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. The Company monitors the availability of inputs that are significant to the measurement of fair value to assess the appropriate categorization of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, the Company’s policy is to recognize significant transfers between levels at the end of the reporting period. The significance of transfers between levels is evaluated based upon the nature of the financial instrument and size of the transfer relative to total net assets available for benefits. The Company’s cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair value due to their short maturities.
Deferred offering costs	Deferred offering costs Deferred offering costs, consisting of legal, accounting and other fees and costs relating to the Merger were capitalized and recorded on the balance sheets. At the close of the Merger, deferred offering costs were recorded as contra equity. Deferred offering costs capitalized as of March 31, 2023 and December 31, 2022 were $0 and $4.0 million, respectively.
Property and equipment, net	Property and equipment, net Property and equipment are recorded at cost. Expenditures for repairs and maintenance are expensed as incurred. When assets are retired or disposed of, the assets and related accumulated depreciation are eliminated from the accounts, and any resulting gain or loss is included in the determination of net income or loss. Depreciation is calculated using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset. The Company’s property and equipment consist of laboratory equipment and employee-related computers with estimated useful lives of three to five years.
Impairment of long-lived assets	Impairment of long-lived assets The Company evaluates long-lived assets, which consist of laboratory equipment and computers, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized in the Company’s financial statements.
Leases	Leases The Company elected to early adopt ASU No. 2016-02, Leases ("ASC 842") and its associated amendments as of January 1, 2020. In June 2020, the Company entered into a sublease agreement under which it leased laboratory and office facilities, which the Company determined to be an operating lease. At the inception of a contractual arrangement, the Company determines whether the contract contains a lease by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company records the associated lease liability and corresponding right-of-use ("ROU") asset upon commencement of the lease using the implicit rate or a discount rate based on a credit-adjusted secured borrowing rate commensurate with the term of the lease. Operating lease assets represent a right to use an underlying asset for the lease term and operating lease liabilities represent an obligation to make lease payments arising from the lease. Operating lease liabilities with a term greater than one year and their corresponding ROU assets are recognized on the balance sheet at the commencement date of the lease based on the present value of lease payments over the expected lease term. As the Company’s lease does not provide an implicit rate, the Company utilizes the appropriate incremental borrowing rate, determined as the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment. Lease cost is recognized on a straight-line basis over the lease term and variable lease payments are recognized as operating expenses in the period in which the obligation for those payments is incurred. Variable lease payments primarily include common area maintenance, utilities, real estate taxes, insurance, and other operating costs that are passed on from the lessor in proportion to the space leased by the Company. The Company has elected the practical expedient to not separate between lease and non-lease components. Operating ROU assets are reflected in right-of-use asset on the balance sheets. Operating lease liabilities are reflected in accrued expenses and other current liabilities and long-term liabilities on the balance sheets.
Convertible preferred stock	Convertible preferred stock The Company classifies convertible preferred stock outside of stockholders’ deficit on its balance sheet as the requirements of triggering a deemed liquidation event are not within the Company’s control. In the event of a deemed liquidation event, the proceeds from the event are distributed in accordance with liquidation preferences (Note 10). The Company records the issuance of convertible preferred stock at the issuance price less related issuance costs and less any discount arising on allocation of proceeds to one or more derivative features. The Company has not adjusted the carrying values of the convertible preferred stock to its liquidation preference because of the uncertainty as to whether a deemed liquidation event may occur. In February 2023, all outstanding shares of convertible preferred stock were converted into common shares upon the closing of the Merger.
Research and development expenses	Research and development expenses The Company expenses research and development costs as incurred. Research and development expenses consist primarily of costs incurred for the discovery and development of its product candidates and include consultants and supplies to conduct clinical, preclinical, and non-clinical studies, costs to acquire, develop and manufacture supplies for preclinical and clinical testing and other studies, expenses incurred under agreements with contract research organizations, and salaries and related costs, including stock-based compensation, as well as depreciation and other allocated facility-related and overhead expenses. Advance payments for goods or services for future research and development activities are deferred and expensed as the goods are delivered or the related services are performed. The Company estimates clinical and preclinical study expenses based on the services performed pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical studies and clinical trials on the Company’s behalf. In addition, clinical, preclinical, and non-clinical study materials are manufactured by contract manufacturing organizations. In accruing for these services, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. These estimates are based on communications with the third-party service providers and the Company’s estimates of accrued expenses and on information available at each balance sheet date. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly.
Stock-based compensation	Stock-based compensation The Company measures and records the expense related to stock-based payment awards based on the estimated grant date fair value of those awards. The Company recognizes stock-based compensation expense over the requisite service period of the individual award, generally equal to the vesting period and uses the straight-line method to recognize stock-based compensation. The Company uses the Black-Scholes option pricing model to determine the fair value of the stock awards. The Black-Scholes option pricing model requires the Company to make assumptions and judgements about the variables used in the calculations, including the fair value of common stock, expected term, expected volatility of its common stock, risk-free interest rate and expected dividend yield. As the stock-based compensation is based on awards ultimately expected to vest, it is reduced by forfeitures, which the Company accounts for as they occur. The Company classifies equity-based compensation expense in the statement of operations and comprehensive loss in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. Black-Scholes requires the use of subjective assumptions, which determine the fair value of stock-based awards. These assumptions include: • Fair Value of Common Stock—Prior to the Merger, as there had been no public market for the Company’s common stock to date, the estimated fair value of the Company’s common stock was determined by the board of directors as of the date of each option grant with input from management, considering the most recently available third-party valuation of common stock. Following the Merger, the fair value of common stock is based on the closing stock price on the date of grant as reported on the Nasdaq Global Select Market. • Expected Term—The expected term represents the period that the Company’s options are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of the contractual term). The Company has very limited historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants. • Expected Volatility—The expected stock price volatilities are estimated based on the historical and implied volatilities of comparable publicly traded companies as the Company does not have sufficient history of trading its common stock. • Risk-Free Interest Rate—The risk-free interest rates are based on U.S. Treasury yields in effect at the grant date for notes with comparable terms as the awards. • Expected Dividend Yield—The Company has never paid dividends on its common stock and has no plans to do so in the future. Therefore, the Company used an expected dividend of zero. The assumptions underlying these valuations represented the Company’s board of directors' and management’s best estimates, which involved inherent uncertainties and the application of management’s judgment. As a result, if the Company had used significantly different assumptions or estimates, the fair value of its stock-based compensation expense could be materially different.
Income taxes	Income taxes Income taxes are accounted for using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts or existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period of enactment. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. The Company has generated net losses since inception and accordingly has not recorded a provision for income taxes. The Company recognizes a tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained upon examination by the tax authorities, based on the merits of the position. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of its provision for income taxes. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits.
Net loss per share	Net loss per share The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. Convertible preferred stock is a participating security in distributions of the Company. The net loss attributable to common stockholders is not allocated to the convertible preferred shares as the holders of convertible preferred shares do not have a contractual obligation to share in losses. Cumulative dividends on preferred shares are added to net loss to arrive at net loss available to common stockholders. Under the two-class method, basic net loss per share of common stock is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during each period. The weighted-average number of shares of common stock outstanding used in the basic net loss per share calculation does not include unvested restricted common stock as these shares are considered contingently issuable shares until they vest. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock, stock options and unvested early exercised common stock and unvested restricted common stock, which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive. For all periods presented, basic and diluted net loss per share were the same, as any additional share equivalents would be anti-dilutive.
Segments	Segments The Company operates in one segment and, accordingly, no segment disclosures have been presented herein. The Company's long-lived assets are primarily located in the United States. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating and evaluating financial performance.
Comprehensive income (loss)	Comprehensive income (loss) Other comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company did not have any items that required classification as other comprehensive income (loss).
Emerging growth company status	Emerging growth company status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the "JOBS Act"). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.
Recently adopted accounting pronouncements	Recently adopted accounting pronouncements In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes. ASU 2019-12 eliminates certain exceptions related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. It also clarifies and simplifies other aspects of the accounting for income taxes. This guidance was effective for fiscal years beginning after December 15, 2021. The Company adopted ASU 2019-12 on January 1, 2022, and the adoption did not have a material impact on the Company's financial statements. There were no other significant updates not already disclosed in the Company’s audited financial statements for the years ended December 31, 2022 and 2021 to the recently issued accounting standards for the three months ended March 31, 2023.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements as of March 31, 2023 and for the three months ended March 31, 2023 and 2022 have been prepared in conformity with U.S. GAAP, for interim financial information and pursuant to Article 10 of Regulation S-X of the Securities Act of 1933, as amended (the "Securities Act"). Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. These unaudited condensed consolidated financial statements have been prepared on the same basis as the Company’s audited financial statements and include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows. The results for the three months ended March 31, 2023 are not necessarily indicative of the results

expected for the full fiscal year or any subsequent interim period. The condensed balance sheet as of December 31, 2022 has been derived from the audited financial statements at that date but does not include all disclosures required by U.S. GAAP for complete financial statements. Because all of the disclosures required by U.S. GAAP for complete financial statements are not included herein, these unaudited condensed consolidated financial statements and the notes accompanying them should be read in conjunction with Former Enliven’s audited financial statements as of and for the year ended December 31, 2022. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification ("ASC"), and Accounting Standards Update, ("ASU"), of the Financial Accounting Standards Board ("FASB").

Use of estimates

The preparation of financial statements in accordance 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 at the date of the financial statements, and the reported amounts of income and expense during the reporting period. The most significant estimates relate to the determination of fair value of the Company’s common stock, stock-based compensation and accrued research and development expenses. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, and makes adjustments when facts and circumstances dictate.

Cash and cash equivalents

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents are recorded at cost, which approximates fair value. As of March 31, 2023 and December 31, 2022, cash and cash equivalents consisted primarily of checking and money market funds composed of U.S. government obligations.

Restricted cash

The Company classifies all cash whose use is limited by contractual provisions as restricted cash. Restricted cash arises from the requirement for the Company to maintain cash of $54,000 as collateral for a sublease with the facility’s landlord. As of March 31, 2023 and December 31, 2022, $54,000 of restricted cash was reflected in restricted cash in the balance sheets.

Concentrations of credit risk and off-balance sheet risk

The Company maintains its cash accounts and money market funds that at times exceed insured limits. As of March 31, 2023 and December 31, 2022, the Company’s cash balances exceeded those that are federally insured. To date, the Company has not recognized any losses caused by uninsured balances.

Fair value measurements

Financial assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the price the Company would receive to sell an investment in a timely transaction or pay to transfer a liability in a timely transaction with an independent buyer in the principal market, or in the absence of a principal market, the most advantageous market for the investment or liability. A framework is used for measuring fair value utilizing a three-tier hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3).

The three levels of the fair value hierarchy are as follows:

•

Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities;

•

Level 2—Quoted prices in markets that are not considered to be active or financial instrument valuations for which all significant inputs are observable, either directly or indirectly; and

•

Level 3—Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

Financial instruments are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and considers factors specific to the investment. To the extent that the valuation is based on models or inputs that are less observable

or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3.

The Company monitors the availability of inputs that are significant to the measurement of fair value to assess the appropriate categorization of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, the Company’s policy is to recognize significant transfers between levels at the end of the reporting period. The significance of transfers between levels is evaluated based upon the nature of the financial instrument and size of the transfer relative to total net assets available for benefits.

The Company’s cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair value due to their short maturities.

Deferred offering costs

Deferred offering costs, consisting of legal, accounting and other fees and costs relating to the Merger were capitalized and recorded on the balance sheets. At the close of the Merger, deferred offering costs were recorded as contra equity. Deferred offering costs capitalized as of March 31, 2023 and December 31, 2022 were $0 and $4.0 million, respectively.

Property and equipment, net

Property and equipment are recorded at cost. Expenditures for repairs and maintenance are expensed as incurred. When assets are retired or disposed of, the assets and related accumulated depreciation are eliminated from the accounts, and any resulting gain or loss is included in the determination of net income or loss. Depreciation is calculated using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.

The Company’s property and equipment consist of laboratory equipment and employee-related computers with estimated useful lives of three to five years.

Impairment of long-lived assets

The Company evaluates long-lived assets, which consist of laboratory equipment and computers, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized in the Company’s financial statements.

Leases

The Company elected to early adopt ASU No. 2016-02, Leases ("ASC 842") and its associated amendments as of January 1, 2020. In June 2020, the Company entered into a sublease agreement under which it leased laboratory and office facilities, which the Company determined to be an operating lease. At the inception of a contractual arrangement, the Company determines whether the contract contains a lease by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company records the associated lease liability and corresponding right-of-use ("ROU") asset upon commencement of the lease using the implicit rate or a discount rate based on a credit-adjusted secured borrowing rate commensurate with the term of the lease. Operating lease assets represent a right to use an underlying asset for the lease term and operating lease liabilities represent an obligation to make lease payments arising from the lease. Operating lease liabilities with a term greater than one year and their corresponding ROU assets are recognized on the balance sheet at the commencement date of the lease based on the present value of lease payments over the expected lease term. As the Company’s lease does not provide an implicit rate, the Company utilizes the appropriate incremental borrowing rate, determined as the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment. Lease cost is recognized on a straight-line basis over the lease term and variable lease payments are recognized as operating expenses in the period in which the obligation for those payments is incurred. Variable lease payments primarily include common area maintenance, utilities, real

estate taxes, insurance, and other operating costs that are passed on from the lessor in proportion to the space leased by the Company. The Company has elected the practical expedient to not separate between lease and non-lease components.

Operating ROU assets are reflected in right-of-use asset on the balance sheets. Operating lease liabilities are reflected in accrued expenses and other current liabilities and long-term liabilities on the balance sheets.

Convertible preferred stock

The Company classifies convertible preferred stock outside of stockholders’ deficit on its balance sheet as the requirements of triggering a deemed liquidation event are not within the Company’s control. In the event of a deemed liquidation event, the proceeds from the event are distributed in accordance with liquidation preferences (Note 10). The Company records the issuance of convertible preferred stock at the issuance price less related issuance costs and less any discount arising on allocation of proceeds to one or more derivative features. The Company has not adjusted the carrying values of the convertible preferred stock to its liquidation preference because of the uncertainty as to whether a deemed liquidation event may occur. In February 2023, all outstanding shares of convertible preferred stock were converted into common shares upon the closing of the Merger.

Research and development expenses

The Company expenses research and development costs as incurred. Research and development expenses consist primarily of costs incurred for the discovery and development of its product candidates and include consultants and supplies to conduct clinical, preclinical, and non-clinical studies, costs to acquire, develop and manufacture supplies for preclinical and clinical testing and other studies, expenses incurred under agreements with contract research organizations, and salaries and related costs, including stock-based compensation, as well as depreciation and other allocated facility-related and overhead expenses. Advance payments for goods or services for future research and development activities are deferred and expensed as the goods are delivered or the related services are performed.

The Company estimates clinical and preclinical study expenses based on the services performed pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical studies and clinical trials on the Company’s behalf. In addition, clinical, preclinical, and non-clinical study materials are manufactured by contract manufacturing organizations. In accruing for these services, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. These estimates are based on communications with the third-party service providers and the Company’s estimates of accrued expenses and on information available at each balance sheet date. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly.

Stock-based compensation

The Company measures and records the expense related to stock-based payment awards based on the estimated grant date fair value of those awards. The Company recognizes stock-based compensation expense over the requisite service period of the individual award, generally equal to the vesting period and uses the straight-line method to recognize stock-based compensation. The Company uses the Black-Scholes option pricing model to determine the fair value of the stock awards. The Black-Scholes option pricing model requires the Company to make assumptions and judgements about the variables used in the calculations, including the fair value of common stock, expected term, expected volatility of its common stock, risk-free interest rate and expected dividend yield. As the stock-based compensation is based on awards ultimately expected to vest, it is reduced by forfeitures, which the Company accounts for as they occur.

The Company classifies equity-based compensation expense in the statement of operations and comprehensive loss in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified.

Black-Scholes requires the use of subjective assumptions, which determine the fair value of stock-based awards. These assumptions include:

•

Fair Value of Common Stock—Prior to the Merger, as there had been no public market for the Company’s common stock to date, the estimated fair value of the Company’s common stock was determined by the board of directors as of the date of each option grant with input from management, considering the most recently available third-party valuation of common stock. Following the Merger, the fair value of common stock is based on the closing stock price on the date of grant as reported on the Nasdaq Global Select Market.

•

Expected Term—The expected term represents the period that the Company’s options are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of the contractual term). The Company has very limited historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants.

•

Expected Volatility—The expected stock price volatilities are estimated based on the historical and implied volatilities of comparable publicly traded companies as the Company does not have sufficient history of trading its common stock.

•

Risk-Free Interest Rate—The risk-free interest rates are based on U.S. Treasury yields in effect at the grant date for notes with comparable terms as the awards.

•

Expected Dividend Yield—The Company has never paid dividends on its common stock and has no plans to do so in the future. Therefore, the Company used an expected dividend of zero.

The assumptions underlying these valuations represented the Company’s board of directors' and management’s best estimates, which involved inherent uncertainties and the application of management’s judgment. As a result, if the Company had used significantly different assumptions or estimates, the fair value of its stock-based compensation expense could be materially different.

Income taxes

Income taxes are accounted for using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts or existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period of enactment. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized.

The Company has generated net losses since inception and accordingly has not recorded a provision for income taxes.

The Company recognizes a tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained upon examination by the tax authorities, based on the merits of the position. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of its provision for income taxes. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits.

Net loss per share

The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. Convertible preferred stock is a participating security in distributions of the Company. The net loss attributable to common stockholders is not allocated to the convertible preferred shares as the holders of convertible preferred shares do not have a contractual obligation to share in losses. Cumulative dividends on preferred shares are added to net loss to arrive at net loss available to common stockholders.

Under the two-class method, basic net loss per share of common stock is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during each period. The weighted-average number of shares of common stock outstanding used in the basic net loss per share calculation does not include unvested restricted common stock as these shares are considered contingently issuable shares until they vest.

Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock, stock options and unvested early exercised common stock and unvested restricted common stock, which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive. For all periods presented, basic and diluted net loss per share were the same, as any additional share equivalents would be anti-dilutive.

Segments

The Company operates in one segment and, accordingly, no segment disclosures have been presented herein. The Company's long-lived assets are primarily located in the United States. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating and evaluating financial performance.

Comprehensive income (loss)

Other comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company did not have any items that required classification as other comprehensive income (loss).

Emerging growth company status

The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the "JOBS Act"). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.

Recently adopted accounting pronouncements

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes. ASU 2019-12 eliminates certain exceptions related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. It also clarifies and simplifies other aspects of the accounting for income taxes. This guidance was effective for fiscal years beginning after December 15, 2021. The Company adopted ASU 2019-12 on January 1, 2022, and the adoption did not have a material impact on the Company's financial statements.

There were no other significant updates not already disclosed in the Company’s audited financial statements for the years ended December 31, 2022 and 2021 to the recently issued accounting standards for the three months ended March 31, 2023.

Stock-Based Compensation - Summary of Restricted Stock Activity (Details) - Restricted Stock	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested, Beginning Balance \| shares	50,457
Number of Shares, Vested \| shares	(11,867)
Number of Shares, Unvested, Ending Balance \| shares	38,590
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance \| $ / shares	$ 0.14
Weighted-Average Grant Date Fair Value, Vested \| $ / shares	0.14
Weighted-Average Grant Date Fair Value, Unvested, Ending Balance \| $ / shares	$ 0.14

Stock-Based Compensation

3 Months Ended

Mar. 31, 2023

Stock-Based Compensation

11. Stock-Based Compensation

Equity Incentive Plans

2019 Equity Incentive Plan

In July 2019, Former Enliven adopted the 2019 Equity Incentive Plan (the “2019 Plan”) pursuant to which its board of directors may grant non-statutory stock options, stock appreciation rights, restricted stock, and restricted stock units to employees and non-employees and incentive stock options only to employees. After giving effect to the exchange ratio, the 2019 Plan initially authorized grants of awards of up to 374,076 shares of Former Enliven’s common stock. In April 2020, the board of directors increased the number of shares of Former Enliven’s common stock authorized for issuance under the 2019 Plan by 2,210,062 to 2,584,138 shares. Additionally, in December 2020, the board of directors approved an increase in the number of shares of Former Enliven’s common stock authorized for issuance under the 2019 Plan by 1,211,791 to 3,795,929 shares. In August 2022, the board of directors approved an increase in the shares authorized under the 2019 Plan of 885,315 shares, for a total authorized amount of 4,681,244.

The 2019 Plan was terminated as of the consummation of the business combination between Former Enliven and the Company, and no shares remain available for future issuance under the 2019 Plan. Any options outstanding under the 2019 Plan remained outstanding and effective.

2016 Stock Incentive Plan

The Company’s 2016 Stock Incentive Plan, (the “2016 Plan”) provided for the grant of restricted stock, restricted stock units, stock appreciation rights, incentive stock options, non-statutory stock options and other stock-based awards to employees, officers, members of the board of directors, consultants and advisors of the Company. As of the effective date of the 2020 Equity Incentive Plan, no shares remained available for future issuance under the 2016 Plan. Any options or awards outstanding under the 2016 Plan remained outstanding and effective.

2020 Equity Incentive Plan

On October 1, 2019, the Company’s board of directors adopted, and on February 26, 2020 the Company’s stockholders approved, the 2020 Equity Incentive Plan, which became effective on March 11, 2020 (the “2020 Plan”). The 2020 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards.

On November 8, 2022, the Company’s board of directors adopted, and on February 22, 2023, the Company’s stockholders approved, the amendment and restatement of the 2020 Plan. Following the 1-to-4 reverse stock split effected on February 23, 2023, the number of shares reserved for issuance under the 2020 Plan is equal to 4,275,000 shares of the Company’s common stock. The number of shares reserved shall be annually increased on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2024 and continuing until, and including, the fiscal year commencing January 1, 2032, equal to the least of (i) 4.5% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (ii) an amount determined by the Company’s board of directors. The shares of common stock underlying any awards that expire, terminate, or are otherwise surrendered, cancelled, forfeited or repurchased by the Company under the 2020 Plan will be added back to the shares of common stock available for issuance under the 2020 Plan. As of March 31, 2023, 3,829,005 shares of the Company’s common stock remained available for issuance under the 2020 Plan.

Awards granted under the Company’s equity plans expire no later than 10 years from the date of grant. Options and restricted stock granted to employees typically vest over a four-year period but may have been granted with different vesting terms.

2020 Employee Stock Purchase Plan

On October 1, 2019, the Company’s board of directors adopted, and on February 26, 2020, the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the “2020 ESPP”), which became effective on March 11, 2020. The 2020 ESPP permits eligible employees who elect to participate, in six-month offering periods, to purchase shares of common stock through payroll deductions at a price equal to 85% of the fair market value of the common stock on the first or last business day of each applicable six-month offering period, whichever is lower. Prior to the business combination between the Former Enliven and the Company, purchase dates under the ESPP occurred on or about June 14 and December 14 each year.

On November 8, 2022, the Company’s board of directors adopted, and on February 22, 2023, the Company’s stockholders approved, an amendment to the ESPP to increase its share reserve. Following the 1-to-4 reverse stock split effected on February 23, 2023, the number of shares reserved for issuance under the 2020 ESPP is equal to 407,133 shares of the Company’s common stock. The number of shares reserved shall be annually increased on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2024 and continuing until, and including, the fiscal year commencing January 1, 2043, equal to the least of (i) 407,133 shares of the Company’s common stock, (ii) 1% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (iii) an amount determined by the Company’s board of directors. As of March 31, 2023, 402,757 shares of the Company’s common stock remained available for issuance under the 2020 ESPP.

Stock Option Repricing

Effective August 9, 2022, the Former Enliven’s board of directors repriced certain previously granted and still outstanding vested and unvested stock option awards under the 2019 Plan. As a result, the exercise price for these awards was lowered to $2.48 per share, which was the fair value of the Former Enliven’s common stock on August 9, 2022. No other terms of the repriced stock options were modified, and the repriced stock options will continue to vest according to their original vesting schedules and will retain their original expiration dates. As a result of the repricing, 2,209,826 vested and unvested stock options outstanding as of August 9, 2022, with original exercise prices ranging from $4.68 to $7.56, were repriced. The repricing on August 9, 2022 resulted in incremental stock-based compensation expense of $1.0 million, of which $0.3 million related to vested stock option awards and was expensed on the repricing date, and $0.7 million related to unvested stock option awards is being amortized on a straight-line basis over the remaining weighted-average vesting period of those awards of 2.9 years.

The following table summarizes the stock plan activity:


	Stock Options Outstanding			Weighted-Average Exercise Price
Outstanding - January 1, 2023		3,316,671		$	2.20
Assumption of options in connection with the Merger		449,900			28.40
Options granted		199,860			25.28
Options exercised and vested		(76,165	)		2.79
Options cancelled and forfeited		—			—
Outstanding - March 31, 2023		3,890,266		$	7.58

The Company records stock-based compensation expense on a straight-line basis over the vesting period. As of March 31, 2023, total compensation cost not yet recognized related to unvested stock options was $11.1 million, which is expected to be recognized over a weighted-average period of 2.4 years.

Restricted stock award activity

Upon formation of Former Enliven in June 2019, Former Enliven issued approximately 3.0 million shares in restricted common stock to its founders at approximately $0.0003 per share. 25% of the shares vested immediately upon issuance, with the remaining shares vesting evenly over 36 or 48 months. Vesting may be accelerated upon a change in control, as defined in the holder agreements. If the holders cease to have a business relationship with the Company, any unvested shares held by these individuals may be repurchased at their original purchase price. The unvested restricted stock is not considered outstanding for accounting purposes until the shares vest. As of March 31, 2023 and December 31, 2022, there were 20,749 and 41,499 shares subject to repurchase, respectively.

Additionally, between 2019 and 2020, Former Enliven issued a total of 197,262 shares of restricted stock to employees and consultants for aggregate consideration of $27,000. The purchase price of the restricted stock was the estimated fair value on the grant date. The restricted stock awards are subject to vesting over a period of four to five years, and vesting may be accelerated upon a change in control, as defined in the holder agreements. If the holders cease to have a business relationship with the Company, any unvested shares held by these individuals may be repurchased at their original purchase price. The unvested restricted stock is not considered outstanding for accounting purposes until the shares vest.

The following summarizes restricted stock activity:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested - January 1, 2023		50,457		$	0.14
Granted		—			—
Vested		(11,867	)		0.14
Forfeited		—			—
Unvested - March 31, 2023		38,590		$	0.14

As of March 31, 2023, total compensation cost not yet recognized was immaterial.

Stock-based compensation expense

The allocation of stock-based compensation expense was as follows (in thousands):


	Three Months Ended March 31,
	2023		2022
Research and development		492		349
General and administrative		1,770		305
Total stock-based compensation expense	$	2,262	$	654

The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes model. The following summarizes the inputs used:


	Three Months Ended March 31,
	2023		2022
Stock Price	$25.28		$6.78
Expected term (years)	5.8		6.0 - 6.3
Expected volatility	83%		80%
Risk-free interest rate	4.1%		1.6% - 2.0%
Expected dividend yield		—		—

Leases - Additional Information (Details)	1 Months Ended			3 Months Ended
Leases - Additional Information (Details)	Apr. 30, 2022	Mar. 31, 2021 USD ($)	Jun. 30, 2020 ft²	Mar. 31, 2023 USD ($) ft²	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Mar. 01, 2021 ft²	Feb. 28, 2021 ft²
Leases [Abstract]
Area of leased office and laboratory space \| ft²			6,782
Lease expiration date			Dec. 30, 2021
Square feet of office space leased \| ft²				18,170			9,277	2,495
Lease and rental expense		$ 12,000		$ 81,000	$ 41,000
Lease renewal term for office space extended date	Dec. 30, 2024
Lease commencement date				Jul. 31, 2022
Incremental borrowing rate of right of used assets and lease liabilities				400.00%
Remaining lease liability				$ 600,000		$ 600,000
Remaining operating lease right of use asset				$ 600,000		$ 600,000

Property and Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2023

Property Plant And Equipment [Abstract]

Schedule of Property and Equipment, Net

Property and equipment, net consisted of the following (dollar amounts in thousands):


	Estimated Useful Life in Years	As of March 31, 2023			As of December 31, 2022
Laboratory equipment	5	$	1,191		$	1,191
Computer equipment	3		103			73
Property and equipment, gross			1,294			1,264
Less: accumulated depreciation			(441	)		(374	)
Property and equipment, net		$	853		$	890

Preferred Stock and Convertible Preferred Stock - Additional Information (Details) - $ / shares	Feb. 23, 2023	Mar. 31, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Preferred stock, shares authorized		10,000,000	0
Preferred stock, par value		$ 0.001	$ 0.001
Business acquisition, exchange ratio	0.2951%
Preferred stock, shares issued		0	0
Preferred stock, shares outstanding		0	0
Merger Agreement
Class Of Stock [Line Items]
Business acquisition, common shares issued	34,426,351
Convertible Preferred Stock
Class Of Stock [Line Items]
Preferred stock, shares authorized		0	61,730,064
Preferred stock, par value		$ 0.0001	$ 0.0001
Business acquisition, exchange ratio	0.2951%
Preferred stock, shares issued		0	61,730,064
Preferred stock, shares outstanding		0	61,730,064
Convertible Preferred Stock \| Merger Agreement
Class Of Stock [Line Items]
Preferred stock, shares issued		0	0