0000950170-24-024008 | 10-K | XBRL Viewer

Income Taxes - Summary of Reconciliation of Income Tax (Expense) Benefit Statutory Tax Rate to Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax benefit computed at statutory rates	$ 29,054	$ 21,429	$ 18,757
Change in valuation allowance	(32,248)	(33,936)	(20,111)
Foreign rate differential	(2)	1	(19)
State income taxes, net of federal benefit	7,653	5,824
State deferred tax true-up due to change in apportionment	2,030	6,517
Unrecognized tax benefits	(9,940)
Research and development credits, net of uncertain tax position	3,275	2,130	1,331
Executive compensation limitation	(3,971)
Other	282	(1,984)	189
Income tax (expense) benefit	$ (3,867)	$ (19)	$ 147

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

The following table presents the Company’s financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of December 31, 2023 (in thousands):


	Valuation	Amortized		Unrealized		Unrealized			Fair
	Hierarchy	Cost		Gains		Losses			Value
Money market funds	Level 1	$	493	$	—	$	—		$	493
Commercial paper	Level 2		94,261		—		(55	)		94,206
U.S. government bonds	Level 2		137,976		250		(142	)		138,084
Agency bonds	Level 2		45,481		152		(44	)		45,589
Corporate debt securities	Level 2		3,177		—		(12	)		3,165
U.S. Treasury securities	Level 2		71,754		36		(1	)		71,789
Agency discount securities	Level 2		7,975		1		—			7,976
Total cash equivalents and marketable securities		$	361,117	$	439	$	(254	)	$	361,302
Classified as:
Cash equivalents									$	98,593
Marketable securities										262,709
Total cash equivalents and marketable securities									$	361,302

The following table presents the Company’s financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of December 31, 2022 (in thousands):


	Valuation	Amortized		Unrealized		Unrealized			Fair
	Hierarchy	Cost		Gains		Losses			Value
Money market funds	Level 1	$	18,224	$	—	$	—		$	18,224
Commercial paper	Level 2		104,279		1		(84	)		104,196
U.S. government bonds	Level 2		18,225		1		(109	)		18,117
Agency bonds	Level 2		13,986		—		(78	)		13,908
Corporate debt securities	Level 2		10,488		—		(62	)		10,426
U.S. Treasury securities	Level 2		7,414		1		(21	)		7,394
Agency discount securities	Level 2		5,216		9		—			5,225
Non-U.S. debt securities	Level 2		3,975		—		(20	)		3,955
Total cash equivalents and marketable securities		$	181,807	$	12	$	(374	)	$	181,445
Classified as:
Cash equivalents									$	48,540
Marketable securities										132,905
Total cash equivalents and marketable securities									$	181,445

The valuation techniques used to measure the fair values of the Company’s Level 2 financial instruments, which generally have counterparties with high credit ratings, are based on quoted market prices when available. If quoted market prices are not available, the fair value for the security is estimated under the market or income approach using pricing models with market observable inputs.

The following table summarizes the Company’s cash equivalents and marketable securities by contractual maturity as of December 31, 2023 (in thousands):


Within one year	$	290,756
After one year through two years		70,546
Total cash equivalents and marketable securities	$	361,302

During 2023 and 2022, the Company did not recognize an allowance for credit-related losses or an other-than-temporary impairment charge for any of its investments, respectively.

- 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

Income Taxes - Summary of Income Tax (Expense) Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
State		$ (3)	$ (2)
Foreign	$ (3,740)	(16)	(1)
Total current	(3,740)	(19)	(3)
Deferred:
Federal			150
Foreign	(127)
Total deferred	(127)		150
Income tax (expense) benefit	$ (3,867)	$ (19)	$ 147

- Definition

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

+ References + Details

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Line Items]
Deferred tax assets, valuation allowance	$ 108,230	$ 75,982
Deferred tax assets, change in valuation allowance	32,200
Unrecognized tax benefits, exclusive of interest	12,098	1,584	$ 851	$ 329
Increase related to prior year positions	9,400
Decrease in income tax expense due to unrecognized tax benefits if recognized	(3,100)
Interest related to uncertain tax positions	$ 600
Israel Tax Authority \| Earliest Tax Year
Income Tax Disclosure [Line Items]
Tax year under examination	2018
Israel Tax Authority \| Latest Tax Year
Income Tax Disclosure [Line Items]
Tax year under examination	2021
Federal
Income Tax Disclosure [Line Items]
Accumulated tax loss carryforward	$ 195,000	160,900
Federal \| Research and Development Credit Carryforwards
Income Tax Disclosure [Line Items]
Carryforward tax losses expiration year	2040
Credit carryforwards	$ 7,500	4,300
State
Income Tax Disclosure [Line Items]
Accumulated tax loss carryforward	302,800	169,800
State \| Research and Development Credit Carryforwards
Income Tax Disclosure [Line Items]
Credit carryforwards	3,200	1,800
Israel
Income Tax Disclosure [Line Items]
Accumulated tax loss carryforward	$ 30,400	$ 32,100
California \| State
Income Tax Disclosure [Line Items]
Carryforward tax losses expiration year	2039

Term Loan Facilities (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of Maturities of Principal Obligations

As of December 31, 2023, the Company’s maturities of principal obligations under the term loan were as follows (in thousands):


2024	$	—
2025		10,774
2026		13,036
2027		1,190
Total principal outstanding		25,000
Plus accumulated accretion of final payment fee		388
Less unamortized debt discount		(593	)
Total net carry value		24,795
Term loan, current portion		—
Term loan, non-current, net	$	24,795

Net Loss Per Share - Schedule of Weighted-average Shares Outstanding Used to Calculate Basic and Diluted Net Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
The Weighted-average Shares Outstanding Used To Calculate Basic And Diluted Net Loss Per Share [Line Items]
Weighted-average shares used to compute net loss per share, basic	71,172,870	34,806,349	20,098,340
Weighted-average shares used to compute net loss per share, diluted	71,172,870	34,806,349	20,098,340
Common Stock
The Weighted-average Shares Outstanding Used To Calculate Basic And Diluted Net Loss Per Share [Line Items]
Weighted-average shares used to compute net loss per share, basic	70,310,671	31,767,914	20,098,340
Weighted-average shares used to compute net loss per share, diluted	70,310,671	31,767,914	20,098,340
Pre-funded Warrants
The Weighted-average Shares Outstanding Used To Calculate Basic And Diluted Net Loss Per Share [Line Items]
Weighted-average shares used to compute net loss per share, basic	862,199	3,038,435
Weighted-average shares used to compute net loss per share, diluted	862,199	3,038,435

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 316,161	$ 55,255
Marketable securities	262,709	132,905
Prepaid and other current assets	14,664	7,920
Total current assets	593,534	196,080
Operating lease right-of-use assets	2,293	363
Property and equipment, net	46	92
Other assets	396	289
Total assets	596,269	196,824
Current liabilities:
Accounts payable	8,585	12,502
Accrued expenses	20,530	11,944
Operating lease liabilities, current	496	168
Total current liabilities	29,611	24,614
Operating lease liabilities, non-current	1,817	186
Term loan, non-current, net	24,795	20,192
Other non-current liabilities	3,740
Total liabilities	59,963	44,992
Commitments and contingencies (Note 5)
Stockholders’ equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized, none issued and outstanding
Common stock, $0.001 par value; 200,000,000 and 100,000,000 shares authorized and 93,269,377 and 50,560,590 shares issued and outstanding as of December 31, 2023 and 2022, respectively	93	51
Additional paid-in capital	993,455	467,374
Accumulated other comprehensive income (loss)	190	(350)
Accumulated deficit	(457,432)	(315,243)
Total stockholders’ equity	536,306	151,832
Total liabilities and stockholders’ equity	$ 596,269	$ 196,824

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended					12 Months Ended
	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Feb. 28, 2023	Jul. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 08, 2023	Jun. 05, 2023	Mar. 31, 2021
Subsidiary Sale Of Stock [Line Items]
Authorized shares of common stock	200,000,000					200,000,000	100,000,000		200,000,000	100,000,000
Authorized shares of preferred stock	10,000,000					10,000,000	10,000,000		10,000,000
Proceeds from issuance of common stock, net of commissions and offering expenses						$ 268	$ 50	$ 144
Common stock, par value	$ 0.001					$ 0.001	$ 0.001
Pre-funded Warrants
Subsidiary Sale Of Stock [Line Items]
Percentage of ownership limitation					9.99%
Percentage of ownership prior to issuance					4.99%
Warrants
Subsidiary Sale Of Stock [Line Items]
Percentage of ownership limitation					9.99%
Percentage of ownership prior to issuance					4.99%
Maximum \| Pre-funded Warrants
Subsidiary Sale Of Stock [Line Items]
Percentage of ownership limitation					19.99%
Maximum \| Warrants
Subsidiary Sale Of Stock [Line Items]
Percentage of ownership limitation					19.99%
Public Offerings
Subsidiary Sale Of Stock [Line Items]
Proceeds from issuance of common stock, net of commissions and offering expenses	$ 161,800		$ 296,800		$ 88,200
Public offering description					In July 2022, the Company completed an underwritten public offering of its common stock, warrants to purchase shares of its common stock and pre-funded warrants to purchase shares of its common stock. The Company sold 18,675,466 shares of its common stock with accompanying warrants to purchase up to 9,337,733 shares of its common stock at a combined public offering price of $3.55 per share. The Company also sold 7,944,252 pre-funded warrants to purchase shares of its common stock with accompanying warrants to purchase up to 3,972,126 shares of its common stock at a combined public offering price of $3.549 per pre-funded warrant, which represents the per share public offering price for the common stock less $0.001 per share, the exercise price for each pre-funded warrant. The Company raised net proceeds of $88.2 million, after deducting underwriting discounts and commissions of $5.7 million and other offering costs of $0.6 million.
Shares issued and sold	17,567,567		19,461,538		18,675,466
Offering price per share					$ 3.55
Underwriting discounts and commissions	$ 10,400		$ 19,000		$ 5,700
Other offering costs	$ 400		$ 500		$ 600
Common stock, par value	$ 0.001				$ 0.001	0.001
Offering price per share	$ 9.25		$ 16.25			9.25
Public Offerings \| Pre-funded Warrants
Subsidiary Sale Of Stock [Line Items]
Number of prefunded warrants issued during period	1,081,081				7,944,252
Combined price of prefunded and common stock warrant					$ 3.549
Offering price per share	$ 9.249					$ 9.249
Public Offerings \| Maximum
Subsidiary Sale Of Stock [Line Items]
Warrants to purchase shares of common stock					9,337,733
Public Offerings \| Maximum \| Pre-funded Warrants
Subsidiary Sale Of Stock [Line Items]
Warrants to purchase shares of common stock					3,972,126
Public Offerings \| A T M Facility
Subsidiary Sale Of Stock [Line Items]
Maximum value of common stock to be issued under agreement				$ 150,000							$ 75,000
Public Offerings \| Leerink Partners LLC and Cantor Fitzgerald & Co
Subsidiary Sale Of Stock [Line Items]
Proceeds from issuance of common stock, net of commissions and offering expenses		$ 23,700		$ 13,400			$ 28,500	$ 3,300
Shares issued and sold		1,200,539		968,000			3,948,611	186,546
Common stock remaining for future sales						$ 125,900
Public Offerings \| Leerink Partners LLC and Cantor Fitzgerald & Co \| Maximum
Subsidiary Sale Of Stock [Line Items]
Selling commission per shares sold percentage											3.00%

Net Loss Per Share -Schedule of Outstanding Potentially Dilutive Securities Excluded From Calculation of Diluted Net Loss (Parenthetical) (Details)	Dec. 31, 2023 shares
Class Of Warrant Or Right [Line Items]
Pre- Funded Warrants excluded	12,293,887
Pre-funded Warrants
Class Of Warrant Or Right [Line Items]
Pre- Funded Warrants excluded	1,881,081

Commitments and Contingencies - Schedule of Future Minimum Lease Payments Under Non-cancellable Operating Lease Obligations (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2024	$ 774
2025	917
2026	937
2027	240
Total undiscounted future minimum lease payments	2,868
Less: imputed interest	(555)
Present value of operating lease liability	$ 2,313

Income Taxes - Summary of Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Line Items]
Research and development expenses	$ 41,834	$ 18,927
Stock-based compensation	2,924	4,328
Accrued expenses	307	317
Operating lease liabilities	629	98
Other	378	244
Gross deferred tax assets	108,945	76,301
Less: valuation allowance	(108,230)	(75,982)
Total deferred tax assets	715	319
Operating lease right-of-use assets	(623)	(100)
Total deferred tax liabilities	(623)	(100)
Net deferred tax assets	92	219
United States
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 62,873	45,002
Israel
Income Tax Disclosure [Line Items]
Net operating loss carryforwards		$ 7,385

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net Income (Loss)	$ (142,189)	$ (102,026)	$ (90,122)

- Definition

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

+ References

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Reference 36: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-Based Compensation - Summary of Stock-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 16,106	$ 10,356	$ 8,678
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	7,010	4,094	2,966
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 9,096	$ 6,262	$ 5,712

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Stock Option Activity

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


						Weighted-
				Weighted-		Average
				Average		Remaining		Aggregate
	Number of			Exercise		Contractual		Intrinsic
	Options			Price		Term		Value
						(In years)		(In thousands)
Balance outstanding as of December 31, 2022		3,161,917		$	12.80		7.9	$	16,612
Granted		1,952,900			14.65
Exercised		(247,162	)		2.95
Cancelled and forfeited		(181,078	)		12.40
Balance outstanding as of December 31, 2023		4,686,577		$	14.11		7.9	$	11,712
Exercisable as of December 31, 2023		2,043,280		$	14.70		6.6	$	8,123

Summary of Estimated Weighted-Average Grant Date Fair Value of Options Granted Using Black-Scholes Option-Pricing Model

The following table presents the weighted-average grant date fair value of options granted for the periods presented and the assumptions used to estimate those values using a Black-Scholes option pricing model:


	Year Ended December 31,
	2023	2022	2021
Weighted-average grant date fair value	$11.43	$3.38	$16.18
Expected term (years)	5.5-6.1	5.5-6.3	5.5-6.1
Expected volatility	91.5-99.2%	89.9-91.0%	86.9-91.9%
Risk-free interest rate	3.4-4.6%	1.6-3.9%	0.7-1.3%
Expected dividend	—	—	—

Summary of RSU and PSU Activity

The following table summarizes RSU and PSU activity for the year ended December 31, 2023:


	RSUs					PSUs
	Number of Shares			Weighted-Average Grant Date Fair Value per Share		Number of Shares			Weighted-Average Grant Date Fair Value per Share
Balance outstanding as of December 31, 2022		645,986		$	5.43		449,752		$	6.25
Granted		379,075			15.02		—			—
Vested		(334,688	)		5.36		(150,584	)		6.82
Canceled		(1,991	)		11.80		—			—
Balance outstanding as of December 31, 2023		688,382			10.72		299,168			5.96

Summary of Stock-Based Compensation

The Company recorded stock-based compensation for the periods indicated as follows (in thousands):


	Year Ended December 31,
	2023		2022		2021
Research and development	$	7,010	$	4,094	$	2,966
General and administrative		9,096		6,262		5,712
Total stock-based compensation	$	16,106	$	10,356	$	8,678

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

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating expenses:
Research and development	$ 122,230	$ 80,796	$ 70,330
General and administrative	28,974	21,453	19,413
Total operating expenses	151,204	102,249	89,743
Loss from operations	(151,204)	(102,249)	(89,743)
Interest expense	(4,794)	(1,922)	(674)
Interest income and other, net	17,676	2,164	148
Net loss before income tax	(138,322)	(102,007)	(90,269)
Income tax (expense) benefit	(3,867)	(19)	147
Net loss	(142,189)	(102,026)	(90,122)
Other comprehensive income (loss):
Unrealized gain (loss) on marketable securities	547	(299)	(71)
Foreign currency translation adjustments	(7)	13	17
Total other comprehensive income (loss)	540	(286)	(54)
Comprehensive loss	$ (141,649)	$ (102,312)	$ (90,176)
Net loss per share, basic	$ (2)	$ (2.93)	$ (4.48)
Net loss per share, diluted	$ (2)	$ (2.93)	$ (4.48)
Weighted-average shares used to compute net loss per share, basic	71,172,870	34,806,349	20,098,340
Weighted-average shares used to compute net loss per share, diluted	71,172,870	34,806,349	20,098,340

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Schedule of Weighted-average Shares Outstanding Used to Calculate Basic and Diluted Net Loss Per Share

The following table presents the weighted-average shares outstanding used to calculate basic and diluted net loss per share:


	Year Ended December 31,
	2023		2022		2021
Common stock		70,310,671		31,767,914		20,098,340
Pre-funded warrants		862,199		3,038,435		—
Total		71,172,870		34,806,349		20,098,340

Schedule of Outstanding Potentially Dilutive Securities Excluded From Calculation of Diluted Net Loss

The following table presents potentially dilutive common stock equivalents that have been excluded from the calculation of diluted net loss per share for the periods indicated due to their anti-dilutive effect:


	December 31,
	2023		2022		2021
Stock options outstanding		4,686,577		3,161,917		2,406,668
RSUs and PSUs outstanding		987,550		1,095,738		106,394
Warrants to purchase common stock outstanding1		10,412,806		13,166,283		58,923
Conversion feature related to outstanding term loan		590,816		—		—
Total		16,677,749		17,423,938		2,571,985

1 Excludes pre-funded warrants to purchase 1,881,081 common shares as they are required to be included in basic and diluted net loss per share.

Organization and Basis of Presentation

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Basis of Presentation

1. Organization and Basis of Presentation

Description of Business

89bio, Inc. (“89bio” or the “Company”) is a clinical-stage biopharmaceutical company focused on the development and commercialization of innovative therapies for the treatment of liver and cardio-metabolic diseases. The Company’s lead product candidate, pegozafermin, a specifically engineered glycoPEGylated analog of fibroblast growth factor 21 (“FGF21”), is currently being developed for the treatment of nonalcoholic steatohepatitis (“NASH”) (also known as metabolic dysfunction-associated steatohepatitis (“MASH”)) and for the treatment of severe hypertriglyceridemia (“SHTG”).

89bio, Inc. was formed as a Delaware corporation in June 2019 to carry on the business of 89Bio Ltd., which was incorporated in Israel in January 2018.

Liquidity

The Company has incurred significant losses and negative cash flows from operations since inception and had an accumulated deficit of $457.4 million as of December 31, 2023. The Company has historically financed its operations primarily through the sale of equity securities, including warrants, and from borrowings under term loan facilities. To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any revenue from commercial products. The Company expects operating losses to continue and increase for the foreseeable future as the Company progresses its clinical development activities for its product candidates.

The Company believes its existing cash, cash equivalents and marketable securities of $578.9 million as of December 31, 2023 will be sufficient to fund its planned operating expense and capital expenditure requirements for a period of at least one year from the date of the issuance of these financial statements.

Stockholders' Equity

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Stockholders' Equity

7. Stockholders’ Equity

Changes in Authorized Capital Stock

On June 5, 2023, the Company’s stockholders approved and, on June 8, 2023, the Company filed a Certificate of Amendment to the Second Amended and Restated Certificate of Incorporation to increase the total number of authorized shares of common stock from 100.0 million to 200.0 million. The total number of shares of preferred stock authorized for issuance by the Company remained unchanged at 10.0 million.

As of December 31, 2023, common stock reserved for future issuance, on an as-if-converted basis, were as follows:


Stock options outstanding			4,686,577
RSUs and PSUs outstanding			987,550
Shares available for future grants under equity incentive plans			1,790,684
Shares available for future issuance under the employee stock purchase plan			1,207,607
Warrants to purchase common stock outstanding			10,412,806
Pre-funded warrants to purchase common stock outstanding			1,881,081
Conversion feature related to outstanding term loan			590,816
Total shares of common stock reserved			21,557,121

At-the-Market Offerings

In March 2021, the Company entered into an at-the-market sales agreement (as amended, the “Sales Agreement”) with Leerink Partners LLC and Cantor Fitzgerald & Co. (the “Sales Agents”) pursuant to which the Company may offer and sell shares up to $75.0 million of its common stock (the “2021 ATM Facility”) from time to time pursuant to an effective registration statement. The Sales Agents are entitled to compensation at a commission of up to 3.0% of the aggregate gross sales price per share sold under the Sales Agreement. In 2021 and 2022, the Company sold 186,546 and 3,948,611 shares of its common stock under the 2021 ATM Facility and received net proceeds of $3.3 million and $28.5 million, respectively. In February 2023, the Company sold 968,000 shares of its common stock under the 2021 ATM Facility and received net proceeds of $13.4 million.

In February 2023, the Company entered into an amendment to the Sales Agreement, pursuant to which the Company may offer and sell up to $150.0 million of its common stock (the “2023 ATM Facility”) pursuant to an effective registration statement. In June 2023, the Company sold 1,200,539 shares of its common stock under the 2023 ATM Facility and received net proceeds of $23.7 million. As of December 31, 2023, there was $125.9 million remaining for future sales under the 2023 ATM Facility.

Underwritten Public Offerings

In July 2022, the Company completed an underwritten public offering of its common stock, warrants to purchase shares of its common stock and pre-funded warrants to purchase shares of its common stock. The Company sold 18,675,466 shares of its common stock with accompanying warrants to purchase up to 9,337,733 shares of its common stock at a combined public offering price of $3.55 per share. The Company also sold 7,944,252 pre-funded warrants to purchase shares of its common stock with accompanying warrants to purchase up to 3,972,126 shares of its common stock at a combined public offering price of $3.549 per pre-funded warrant, which represents the per share public offering price for the common stock less $0.001 per share, the exercise price for each pre-funded warrant. The Company raised net proceeds of $88.2 million, after deducting underwriting discounts and commissions of $5.7 million and other offering costs of $0.6 million.

The exercise of the outstanding warrants is subject to a beneficial ownership limitation of 9.99%, or at the election of the holder prior to the issuance of the warrant, 4.99%. The exercise of the outstanding pre-funded warrants is subject to a beneficial ownership limitation of 9.99%, or at the election of the holder prior to the issuance of the pre-funded warrant, 4.99%, which a holder may increase or decrease from time to time but shall not exceed 19.99%. The exercise price and number of shares of common stock issuable upon the exercise of the warrants and pre-funded warrants are subject to adjustment in the event of any stock dividends, stock splits, reverse stock split, recapitalization, or reorganization or similar transaction, as described in the agreements. Under certain circumstances, the warrants and pre-funded warrants may be exercisable on a “cashless” basis. The warrants and pre-funded warrants were classified as a component of stockholders’ equity and additional paid-in capital because such warrants and pre-funded warrants (i) are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, (ii) are immediately exercisable, (iii) do not embody an obligation for the Company to repurchase its shares, (iv) permit the holders to receive a fixed number of common shares upon exercise, (v) are indexed to the Company’s common stock and (vi) meet the equity classification criteria. In addition, the warrants and pre-funded warrants do not provide any guarantee of value or return.

In March 2023, the Company completed an underwritten public offering of its common stock. The Company sold 19,461,538 shares of its common stock at a public offering price of $16.25 per share. The Company raised aggregate proceeds of $296.8 million, net of underwriting discounts and commissions of $19.0 million and other offering costs of $0.5 million.

In December 2023, the Company completed an underwritten public offering of its common stock and pre-funded warrants to purchase shares of its common stock. The Company sold 17,567,567 shares of its common stock at a public offering price of $9.25 per share. The Company also sold 1,081,081 pre-funded warrants to purchase shares of its common stock at $9.249 per share, which represents the per share public offering price for the common stock less $0.001 per share, the exercise price for each pre-funded warrant. The Company raised net proceeds of $161.8 million, after deducting underwriting discounts and commissions of $10.4 million and other offering costs of $0.4 million. The terms and conditions of the pre-funded warrants and rights and obligations of the holder are the same as the pre-funded warrants sold in the July 2022 public offering and are described above.

Common Stock Warrants

As of December 31, 2023, the Company’s outstanding warrants to purchase shares of its common stock were as follows:


	Shares of Common Stock Underlying Warrants		Exercise Price Per Share		Expiration Date
Warrant issued in connection with term loan (SVB)		25,000	$	22.06	June 30, 2025
Warrant issued in connection with term loan (SVB)		33,923	$	19.12	May 28, 2031
Warrants issued in connection with term loan facility (K2HV)		174,093	$	9.76	January 27, 2033
Warrants issued in public offering		10,179,790	$	5.325	July 1, 2024
Pre-funded warrants issued in public offerings		1,881,081	$	0.001	Do not expire
Total outstanding		12,293,887

- Definition

The entire disclosure for equity.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Paragraph 1
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-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

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-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Organization and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Date of incorporation	Jun. 30, 2019
Accumulated deficit	$ (457,432)	$ (315,243)
Cash and cash equivalents and short term available-for-sale securities	$ 578,900

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Commitments and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2018 USD ($)	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Nov. 30, 2023 ft²
Loss Contingencies [Line Items]
Operating leases, rent expense			$ 300	$ 200
Remaining lease term		3 years 1 month 6 days	3 years 1 month 6 days
Incremental borrowing rate used to determine operating lease liability		12.90%	12.90%
Research and development			$ 122,230	$ 80,796	$ 70,330
Teva Agreements
Loss Contingencies [Line Items]
Nonrefundable upfront payment	$ 6,000
Payment upon achievement of certain clinical and commercial milestones	65,000
Asset transfer and license agreement, termination period after written notice			120 days
Asset transfer and license agreement, termination period notice of breach			60 days
Asset transfer and license agreement termination notice period if bankruptcy petition filed			60 days
Research and development		$ 2,500
Milestone payments		$ 2,500
Teva Agreements \| Teva's Development Program
Loss Contingencies [Line Items]
Payment upon achievement of certain clinical and commercial milestones	$ 2,500
San Francisco Office
Loss Contingencies [Line Items]
Operating lease expiration month and year			2025-01
Office space \| ft²		3,600	3,600			17,616

Net Loss Per Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

10. Net Loss Per Share

The following table presents the weighted-average shares outstanding used to calculate basic and diluted net loss per share:


	Year Ended December 31,
	2023		2022		2021
Common stock		70,310,671		31,767,914		20,098,340
Pre-funded warrants		862,199		3,038,435		—
Total		71,172,870		34,806,349		20,098,340


	December 31,
	2023		2022		2021
Stock options outstanding		4,686,577		3,161,917		2,406,668
RSUs and PSUs outstanding		987,550		1,095,738		106,394
Warrants to purchase common stock outstanding1		10,412,806		13,166,283		58,923
Conversion feature related to outstanding term loan		590,816		—		—
Total		16,677,749		17,423,938		2,571,985

1 Excludes pre-funded warrants to purchase 1,881,081 common shares as they are required to be included in basic and diluted net loss per share.

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Summary of Statutory Tax Rates Applicable to Income of Company and Subsidiaries

The Company is taxed according to U.S. federal and state tax laws and Israeli tax laws. The statutory tax rates applicable to the income of the Company and its subsidiaries for the periods presented were as follows:


	Year Ended December 31,
	2023			2022			2021
89bio, Inc.		21	%		21	%		21	%
89Bio Ltd.		23	%		23	%		23	%
89bio Management, Inc.		21	%		21	%		21	%
UAB 89bio Lithuania		15	%		15	%		15	%

Summary of Income Tax (Expense) Benefit

The income tax (expense) benefit for the periods presented is comprised of (in thousands):


				Year Ended December 31,
	2023			2022			2021
Current:
Federal	$	—		$	—		$	—
State	—				(3	)		(2	)
Foreign		(3,740	)		(16	)		(1	)
Total current		(3,740	)		(19	)		(3	)
Deferred:
Federal	—			—				150
State	—			—			—
Foreign		(127	)	—			—
Total deferred		(127	)	—				150
Income tax (expense) benefit	$	(3,867	)	$	(19	)	$	147

Summary of Components of Deferred Tax Assets

Significant components of the Company’s deferred tax assets for the periods presented were as follows (in thousands):


	As of December 31,
	2023			2022
U.S. net operating loss carryforwards	$	62,873		$	45,002
Research and development expenses		41,834			18,927
Israel net operating loss carryforwards		—			7,385
Stock-based compensation		2,924			4,328
Accrued expenses		307			317
Operating lease liabilities		629			98
Other		378			244
Gross deferred tax assets		108,945			76,301
Less: valuation allowance		(108,230	)		(75,982	)
Total deferred tax assets	$	715		$	319

Operating lease right-of-use assets		(623	)		(100	)
Total deferred tax liabilities		(623	)		(100	)
Net deferred tax assets		92			219

Summary of Loss from Operations Before Taxes on Income

The Company recorded a loss from operations, before income tax for the periods presented as follows (in thousands):


	Year Ended December 31,
	2023			2022			2021
United States	$	(138,293	)	$	(101,938	)	$	(91,141	)
Lithuania		(59	)		(7	)		10
Israel		30			(62	)		862
Net loss before income tax	$	(138,322	)	$	(102,007	)	$	(90,269	)

Summary of Reconciliation of Income Tax (Expense) Benefit Statutory Tax Rate to Effective Tax Rate

The reconciliation of income tax (expense) benefit based on the statutory tax rate to the effective tax rate for the periods presented is as follows (in thousands):


	Year Ended December 31,
	2023			2022			2021
Income tax benefit computed at statutory rates	$	29,054		$	21,429		$	18,757
Change in valuation allowance		(32,248	)		(33,936	)		(20,111	)
Foreign rate differential		(2	)		1			(19	)
State income taxes, net of federal benefit		7,653			5,824			—
State deferred tax true-up due to change in apportionment		2,030			6,517			—
Unrecognized tax benefits		(9,940	)		—			—
Research and development credits, net of uncertain tax position		3,275			2,130			1,331
Executive compensation limitation		(3,971	)		—			—
Other		282			(1,984	)		189
Income tax (expense) benefit	$	(3,867	)	$	(19	)	$	147

Summary of Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of gross unrecognized tax benefits for the years ended December 31, 2023, 2022 and 2021 is as follows (in thousands):


	As of December 31,
	2023		2022			2021
Balance beginning of year		1,584		851			329
Increase (decrease) related to prior year positions		9,351		(19	)		(35	)
Increase related to current year positions		1,163		752			557
Balance end of year		12,098		1,584			851

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Lease Payments Under Non-cancellable Operating Lease Obligations

As of December 31, 2023, the undiscounted future minimum lease payments due under the Company’s non-cancellable operating leases were as follows (in thousands):


2024	$	774
2025		917
2026		937
2027		240
Total undiscounted future minimum lease payments	$	2,868
Less: imputed interest		(555	)
Present value of operating lease liabilities	$	2,313

Stock-Based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

8. Stock-Based Compensation

Summary of Equity Incentive Plans

2019 Plan

In September 2019, the Company’s board of directors adopted the 2019 Equity Incentive Plan (the “2019 Plan”), which also became effective in September 2019. The Company initially reserved 2,844,193 shares of common stock for issuance under the 2019 Plan. In addition, the number of shares of common stock reserved for issuance under the 2019 Plan will automatically increase on the first day of January for a period of up to ten years in an amount equal to 4% of the total number of shares of the Company’s capital stock outstanding on the immediately preceding December 31, or a lesser number of shares determined by the Company’s board of directors.

The board of directors determines the period over which options become exercisable and options generally vest over a four-year period, with 25% of options vesting on the first anniversary of employment, and thereafter, the remaining options vesting quarterly, over the following 36-month period. The options expire within ten years from the date of grant. The exercise price of awards granted will not be less than the estimated fair value of the shares on the date of grant. The 2019 Plan also permits the board of directors to grant restricted stock units, which are subject to continued service conditions.

Inducement Plan

In February 2023, the Company’s board of directors adopted the 2023 Inducement Plan (the “Inducement Plan”) and reserved 1,500,000 shares of common stock for issuance. The Inducement Plan is a non-stockholder approved stock plan adopted pursuant to the “inducement exception” provided under Nasdaq listing rules. Under the Inducement Plan, the Company may grant RSUs, PSUs, nonstatutory stock options, stock appreciation rights and restricted stock awards to new hires who satisfy the requirements to be granted inducement grants under Nasdaq rules as an inducement material to the individual’s entry into employment with the Company. The terms of the Inducement Plan are substantially similar to the terms of the 2019 Plan.

Employee Stock Purchase Plan

In October 2019, the Company’s board of directors adopted the 2019 Employee Stock Purchase Plan (“ESPP”), which became effective in November 2019. The Company initially reserved 225,188 shares of common stock for purchase under the ESPP. The number of shares of common stock reserved for issuance under the ESPP will automatically increase on the first day of January for a period of up to ten years in an amount equal to 1% of the total number of shares of the Company’s common stock outstanding on the immediately preceding December 31, or a lesser number of shares determined by the Company’s board of directors. The Company typically makes two offerings each year to eligible employees to purchase stock under the ESPP and each offering has a duration of approximately six months. For each offering period, ESPP participants will purchase shares of common stock at a price per share equal to 85% of the lesser of the fair market value of the Company’s common stock on (1) the first trading day of the applicable offering period or (2) the last trading day of the applicable offering period.

Equity Incentive Plans Activity

Stock Options

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


						Weighted-
				Weighted-		Average
				Average		Remaining		Aggregate
	Number of			Exercise		Contractual		Intrinsic
	Options			Price		Term		Value
						(In years)		(In thousands)
Balance outstanding as of December 31, 2022		3,161,917		$	12.80		7.9	$	16,612
Granted		1,952,900			14.65
Exercised		(247,162	)		2.95
Cancelled and forfeited		(181,078	)		12.40
Balance outstanding as of December 31, 2023		4,686,577		$	14.11		7.9	$	11,712
Exercisable as of December 31, 2023		2,043,280		$	14.70		6.6	$	8,123


	Year Ended December 31,
	2023	2022	2021
Weighted-average grant date fair value	$11.43	$3.38	$16.18
Expected term (years)	5.5-6.1	5.5-6.3	5.5-6.1
Expected volatility	91.5-99.2%	89.9-91.0%	86.9-91.9%
Risk-free interest rate	3.4-4.6%	1.6-3.9%	0.7-1.3%
Expected dividend	—	—	—

Compensation expense related to stock option awards were $11.7 million, $7.6 million and $7.5 million for the years ended December 31, 2023, 2022 and 2021, respectively. The intrinsic value of stock options exercised during the years ended December 31, 2023, 2022 and 2021 was $3.2 million, $0.6 million and $3.6 million, respectively.

As of December 31, 2023, there was $21.7 million of unrecognized stock-based compensation related to unvested stock options, which is expected to be recognized over a weighted-average period of 2.6 years.

Restricted Stock Units and Performance Stock Units

RSUs generally vest annually over a two or three-year period. PSUs generally contain performance conditions associated with corporate goals, such as achievement of certain development milestones, that vests upon achievement over a one to three-year period.

The following table summarizes RSU and PSU activity for the year ended December 31, 2023:


	RSUs					PSUs
	Number of Shares			Weighted-Average Grant Date Fair Value per Share		Number of Shares			Weighted-Average Grant Date Fair Value per Share
Balance outstanding as of December 31, 2022		645,986		$	5.43		449,752		$	6.25
Granted		379,075			15.02		—			—
Vested		(334,688	)		5.36		(150,584	)		6.82
Canceled		(1,991	)		11.80		—			—
Balance outstanding as of December 31, 2023		688,382			10.72		299,168			5.96

Compensation expense related to RSUs and PSUs were $4.3 million, $2.7 million and $1.1 million for the years ended December 31, 2023, 2022 and 2021, respectively. The total fair value of RSUs and PSUs that vested during the years ended December 31, 2023, 2022, and 2021 was $7.5 million, $0.9 million and nil, respectively.

As of December 31, 2023, total unrecognized stock-based compensation expense related to RSUs and PSUs was $5.3 million, which is expected to be recognized over a weighted-average period of 1.5 years.

ESPP

For the years ended December 31, 2023, 2022 and 2021, the number of shares of common stock issued under the Company’s ESPP were 27,217, 18,364 and 10,712, respectively.

Stock-Based Compensation Expense Allocation

The Company recorded stock-based compensation for the periods indicated as follows (in thousands):


	Year Ended December 31,
	2023		2022		2021
Research and development	$	7,010	$	4,094	$	2,966
General and administrative		9,096		6,262		5,712
Total stock-based compensation	$	16,106	$	10,356	$	8,678

Stockholders' Equity - Schedule of Outstanding Warrants to Purchase Shares of Common Stock (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	12,293,887
Warrants Term Loan
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	25,000
Warrant exercise price \| $ / shares	$ 22.06
Warrant expiration date	Jun. 30, 2025
Warrants Term Loan
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	33,923
Warrant exercise price \| $ / shares	$ 19.12
Warrant expiration date	May 28, 2031
Warrants Term Loan
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	174,093
Warrant exercise price \| $ / shares	$ 9.76
Warrant expiration date	Jan. 27, 2033
Warrants Public Offerings
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	10,179,790
Warrant exercise price \| $ / shares	$ 5.325
Warrant expiration date	Jul. 01, 2024
Pre-funded Warrants
Class Of Warrant Or Right [Line Items]
Shares of Common Stock Underlying Warrants	1,881,081
Warrant exercise price \| $ / shares	$ 0.001
Expiration Date	Do not expire

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (142,189)	$ (102,026)	$ (90,122)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	16,106	10,356	8,678
Net (accretion) amortization of investments in marketable securities	(6,242)	(980)	865
Amortization of debt discount and accretion of deferred debt costs	874	764	617
Loss on extinguishment of debt	1,208
Non-cash operating lease expense	223	175
Depreciation	50	65	79
Deferred tax assets	127		(150)
Changes in operating assets and liabilities:
Prepaid and other assets	(6,921)	3,331	(5,672)
Accounts payable	(3,917)	5,659	4,778
Accrued expenses	7,876	1,750	4,146
Operating lease liabilities	(121)	(184)
Other non-current liabilities	3,740
Net cash used in operating activities	(129,186)	(81,090)	(76,781)
Cash flows from investing activities:
Proceeds from sales and maturities of marketable securities	218,133	118,760	148,422
Purchases of marketable securities	(341,148)	(152,696)	(141,200)
Purchases of property and equipment	(4)	(7)	(63)
Net cash (used in) provided by investing activities	(123,019)	(33,943)	7,159
Cash flows from financing activities:
Proceeds from issuance of common stock and warrants in public offerings, net of issuance costs	458,843	88,239
Proceeds from issuance of common stock in at-the-market public offering, net of issuance costs	37,089	28,453	3,289
Proceeds from term loan facility, net of issuance costs	24,363		19,951
Proceeds from issuance of common stock upon exercise of common stock warrants	15,590	1,082
Proceeds from issuance of common stock upon exercise of stock options	633	305	487
Proceeds from issuance of common stock upon ESPP purchases	268	50	144
Payments for taxes related to net share settlement upon vesting of restricted stock units	(2,275)	(298)
Repayment of term loan	(21,400)
Net cash provided by financing activities	513,111	117,831	23,871
Net change in cash and cash equivalents, and restricted cash	260,906	2,798	(45,751)
Cash and cash equivalents, and restricted cash at beginning of period	55,255	52,457	98,208
Cash and cash equivalents, and restricted cash at end of period	316,161	55,255	52,457
Components of cash and cash equivalents, and restricted cash:
Cash and cash equivalents	316,161	55,255	52,432
Restricted cash			25
Total cash and cash equivalents, and restricted cash	316,161	55,255	52,457
Supplemental disclosures of cash information:
Cash paid for interest	2,593	1,076	16
Cash paid for amounts included in the measurement of lease liabilities	185	234
Supplemental disclosures of noncash information:
Unpaid offering costs included in accrued expenses	253
Right-of-use assets obtained in exchange for new operating lease liabilities	2,080
Remeasurement of lease liability and right of use asset in connection with lease modification		$ 338
Issuance of common stock warrant in connection with term loan facility	$ 482		$ 574

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	A T M Facility	Public Offerings	Common Stock	Common Stock A T M Facility	Common Stock Public Offerings	Additional Paid-in Capital	Additional Paid-in Capital A T M Facility	Additional Paid-in Capital Public Offerings	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning balance at Dec. 31, 2020	$ 202,961			$ 20			$ 326,046			$ (10)	$ (123,095)
Beginning balance, shares at Dec. 31, 2020				19,931,660
Issuance of common stock		$ 3,289						$ 3,289
Issuance of common stock, shares					186,546
Issuance of common stock warrants related to term loan facility	574						574
Issuance of common stock upon exercise of stock options	487						487
Issuance of common stock upon exercise of stock options, shares				188,286
Issuance of common stock upon ESPP purchase	144						144
Issuance of common stock upon ESPP purchase, shares				10,712
Stock-based compensation	8,678						8,678
Net loss	(90,122)										(90,122)
Other comprehensive income (loss)	(54)									(54)
Ending balance at Dec. 31, 2021	125,957			$ 20			339,218			(64)	(213,217)
Ending balance, shares at Dec. 31, 2021				20,317,204
Issuance of common stock		28,453	$ 88,239		$ 4	$ 20		28,449	$ 88,219
Issuance of common stock, shares					3,948,611	18,675,466
Issuance of common stock upon exercise of warrants	1,082			$ 4			1,078
Issuance of common stock upon exercise of warrants				4,202,499
Issuance of common stock upon cashless exercise of warrants				$ 3			(3)
Issuance of common stock upon cashless exercise of warrants, shares				3,143,682
Issuance of common stock upon exercise of stock options	305						305
Issuance of common stock upon exercise of stock options, shares				151,061
Issuance of common stock upon vesting of restricted stock units, net of tax withholding for net share settlement	(298)						(298)
Issuance of common stock upon vesting of restricted stock units, net of tax withholding for net share settlement, shares				103,703
Issuance of common stock upon ESPP purchase	50						50
Issuance of common stock upon ESPP purchase, shares				18,364
Stock-based compensation	10,356						10,356
Net loss	(102,026)										(102,026)
Other comprehensive income (loss)	(286)									(286)
Ending balance at Dec. 31, 2022	151,832			$ 51			467,374			(350)	(315,243)
Ending balance, shares at Dec. 31, 2022				50,560,590
Issuance of common stock		$ 37,089	$ 458,590		$ 2	$ 37		$ 37,087	$ 458,553
Issuance of common stock, shares					2,168,539	37,029,105
Issuance of common stock warrants related to term loan facility	482						482
Issuance of common stock upon exercise of warrants	15,590			$ 3			15,587
Issuance of common stock upon exercise of warrants				2,927,570
Issuance of common stock upon exercise of stock options	730						730
Issuance of common stock upon exercise of stock options, shares				247,162
Issuance of common stock upon vesting of restricted stock units, net of tax withholding for net share settlement	(2,732)						(2,732)
Issuance of common stock upon vesting of restricted stock units, net of tax withholding for net share settlement, shares				309,194
Issuance of common stock upon ESPP purchase	268						268
Issuance of common stock upon ESPP purchase, shares				27,217
Stock-based compensation	16,106						16,106
Net loss	(142,189)										(142,189)
Other comprehensive income (loss)	540									540
Ending balance at Dec. 31, 2023	$ 536,306			$ 93			$ 993,455			$ 190	$ (457,432)
Ending balance, shares at Dec. 31, 2023				93,269,377

Income Taxes - Summary of a Reconciliation of The Beginning And Ending Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Balance, beginning of year	$ 1,584	$ 851	$ 329
Increase (decrease) related to prior year positions	9,351	(19)	(35)
Increase related to current year positions	1,163	752	557
Balance, end of year	$ 12,098	$ 1,584	$ 851

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	100,000,000
Common stock, shares issued	93,269,377	50,560,590
Common stock, shares outstanding	93,269,377	50,560,590

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

5. Commitments and Contingencies

Leases

The Company’s operating lease obligations consist of leases for office space in two buildings in San Francisco.

In November 2023, the Company entered into a lease (“2023 Lease”) with respect to approximately 17,616 square feet of office space in San Francisco, California for a lease term commencing in the fourth quarter of 2023 and ending in March 2027. The 2023 Lease does not provide for any extension or renewal options. The 2023 Lease includes an abatement period in which the Company is not required to remit monthly rent payments until April 2024 and has escalating rent payments during the lease term. In addition, the fixed lease payments also cover the Company’s proportionate share of certain operating expenses. The Company recognizes lease expense on a straight-line basis over the term of the 2023 Lease, including any rent-free periods. All fixed lease payments have been included in the measurement of right-of-use assets and lease liabilities in accordance with the Company’s accounting policy to not separate lease and nonlease components of contracts.

The Company also has a lease for approximately 3,600 square feet of office space in San Francisco that expires in January 2025 with an option to renew for an additional year.

For the years ended December 31, 2023 and 2022, lease expense was $0.3 million and $0.2 million, respectively. Rent expense was not material in 2021. Variable lease payments and short-term lease costs were not material for all periods presented. As of December 31, 2023, the weighted-average remaining lease term was 3.1 years and the Company’s weighted-average incremental borrowing rate used to determine operating lease liabilities was 12.9%.

As of December 31, 2023, the undiscounted future minimum lease payments due under the Company’s non-cancellable operating leases were as follows (in thousands):


2024	$	774
2025		917
2026		937
2027		240
Total undiscounted future minimum lease payments	$	2,868
Less: imputed interest		(555	)
Present value of operating lease liabilities	$	2,313

Asset Transfer and License Agreement with Teva Pharmaceutical Industries Ltd

In April 2018, the Company concurrently entered into two Asset Transfer and License Agreements (the “Teva Agreements”) with Teva Pharmaceutical Industries Ltd (“Teva”) under which it acquired certain patents and intellectual property relating to two programs: (1) Teva’s glycoPEGylated FGF21 program, including the compound TEV-47948 (pegozafermin), a glycoPEGylated long-acting FGF21 and (2) Teva’s development program of small molecule inhibitors of Fatty Acid Synthase. Pursuant to the Teva Agreements, the Company paid Teva an initial nonrefundable upfront payment of $6.0 million. In addition, with respect to each product candidate covered by the Teva Agreements, the Company is required to pay Teva $2.5 million upon the achievement of a specified clinical development milestone, and additional payments totaling up to $65.0 million upon achievement of certain commercial milestones. The Company is also obligated to pay Teva tiered royalties at percentages in the low-to-mid single-digits on worldwide net sales on all products containing the Teva compounds.

The Teva Agreements can be terminated (i) by the Company without cause upon 120 days’ written notice to Teva, (ii) by either party, if the other party materially breaches any of its obligations under the Teva Agreements and fails to cure such breach within 60 days after receiving notice thereof, or (iii) by either party, if a bankruptcy petition is filed against the other party and is not dismissed within 60 days. In addition, Teva can also terminate the agreement related to the Company’s glycoPEGylated FGF21 program in the event the Company, or any of its affiliates or sublicensees, challenges any of the Teva patents licensed to the Company, and the challenge is not withdrawn within 30 days of written notice from Teva.

In the fourth quarter of 2023, the Company made a $2.5 million milestone payment to Teva following the achievement of a clinical development milestone under the FGF21 program in SHTG, and accordingly, the Company recorded research and development expense of $2.5 million.

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Summary of Financial Assets Measured at Fair Value on Recurring Basis

The following table presents the Company’s financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of December 31, 2023 (in thousands):


	Valuation	Amortized		Unrealized		Unrealized			Fair
	Hierarchy	Cost		Gains		Losses			Value
Money market funds	Level 1	$	493	$	—	$	—		$	493
Commercial paper	Level 2		94,261		—		(55	)		94,206
U.S. government bonds	Level 2		137,976		250		(142	)		138,084
Agency bonds	Level 2		45,481		152		(44	)		45,589
Corporate debt securities	Level 2		3,177		—		(12	)		3,165
U.S. Treasury securities	Level 2		71,754		36		(1	)		71,789
Agency discount securities	Level 2		7,975		1		—			7,976
Total cash equivalents and marketable securities		$	361,117	$	439	$	(254	)	$	361,302
Classified as:
Cash equivalents									$	98,593
Marketable securities										262,709
Total cash equivalents and marketable securities									$	361,302

The following table presents the Company’s financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of December 31, 2022 (in thousands):


	Valuation	Amortized		Unrealized		Unrealized			Fair
	Hierarchy	Cost		Gains		Losses			Value
Money market funds	Level 1	$	18,224	$	—	$	—		$	18,224
Commercial paper	Level 2		104,279		1		(84	)		104,196
U.S. government bonds	Level 2		18,225		1		(109	)		18,117
Agency bonds	Level 2		13,986		—		(78	)		13,908
Corporate debt securities	Level 2		10,488		—		(62	)		10,426
U.S. Treasury securities	Level 2		7,414		1		(21	)		7,394
Agency discount securities	Level 2		5,216		9		—			5,225
Non-U.S. debt securities	Level 2		3,975		—		(20	)		3,955
Total cash equivalents and marketable securities		$	181,807	$	12	$	(374	)	$	181,445
Classified as:
Cash equivalents									$	48,540
Marketable securities										132,905
Total cash equivalents and marketable securities									$	181,445

Schedule of Contractual Maturities of Cash Equivalents and Marketable Securities

The following table summarizes the Company’s cash equivalents and marketable securities by contractual maturity as of December 31, 2023 (in thousands):


Within one year	$	290,756
After one year through two years		70,546
Total cash equivalents and marketable securities	$	361,302

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2023	Feb. 21, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Registrant Name	89bio, Inc.
Entity Central Index Key	0001785173
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 1,175.6
Entity Common Stock, Shares Outstanding		93,501,210
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Document Financial Statement Error Correction [Flag]	false
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	ETNB
Security Exchange Name	NASDAQ
Entity File Number	001-39122
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-4946844
Entity Address, Address Line One	142 Sansome Street
Entity Address Address Line Two	Second Floor
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94104
City Area Code	415
Local Phone Number	432-9270
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Portions of the registrant’s proxy statement for the 2024 Annual Meeting of Stockholders, to be held on or about May 29, 2024, are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein. Such proxy statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2023.
Auditor Firm ID	185
Auditor Name	KPMG LLP
Auditor Location	San Francisco, California, USA

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Two Thousand And Nineteen Equity Incentive Plan [Member] and Two Thousand And Twenty Three Equity Inducement Plan
Weighted Average Exercise Price
Weighted Average Exercise Price, Exercisable as of December 31, 2023	$ 14.7
Weighted Average Remaining Contractual Term (In years)
Weighted Average Remaining Contractual Term (In years), Exercisable as of December 31, 2023	6 years 7 months 6 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Exercisable as of December 31, 2023	$ 8,123
2023 Inducement Plan and 2019 Employee Stock Purchase Plan
Number of Options
Outstanding, Beginning Balance	3,161,917
Granted	1,952,900
Exercised	(247,162)
Cancelled and forfeited	(181,078)
Outstanding, Ending Balance	4,686,577	3,161,917
Exercisable as of December 31, 2023	2,043,280
Weighted Average Exercise Price
Weighted Average Exercise Price Outstanding, Beginning Balance	$ 12.8
Weighted Average Exercise Price, Granted	14.65
Weighted Average Exercise Price, Exercised	2.95
Weighted Average Exercise Price, Cancelled and forfeited	12.4
Weighted Average Exercise Price Outstanding, Ending Balance	$ 14.11	$ 12.8
Weighted Average Remaining Contractual Term (In years)
Weighted Average Remaining Contractual Term (In years), Outstanding	7 years 10 months 24 days	7 years 10 months 24 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value	$ 11,712	$ 16,612

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segment	1
Stock compensation expense recognized	$ 16,106,000	$ 10,356,000	$ 8,678,000
2021 Loan Agreement
Summary Of Significant Accounting Policies [Line Items]
Debt instrument, final payment fee	500,000
Performance Stock Units (PSUs)
Summary Of Significant Accounting Policies [Line Items]
Stock compensation expense recognized	$ 0
ASU 2020-06
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2023
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
Change in accounting principle, accounting standards update, early adopted [true false]	true
Leasehold Improvements
Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	us-gaap:UsefulLifeShorterOfTermOfLeaseOrAssetUtilityMember
Minimum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	7 years

Stockholders' Equity - Schedule of Shares of Common Stock Available for Future Issuance (Details)	Dec. 31, 2023 shares
Class Of Stock [Line Items]
Total available for future issuance	21,557,121
Stock Options Outstanding
Class Of Stock [Line Items]
Total available for future issuance	4,686,577
Rsus And Psus Outstanding
Class Of Stock [Line Items]
Total available for future issuance	987,550
Equity Incentive Plan
Class Of Stock [Line Items]
Total available for future issuance	1,790,684
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Total available for future issuance	1,207,607
Warrants To Purchase Common Stock
Class Of Stock [Line Items]
Total available for future issuance	10,412,806
Pre-funded Warrants To Purchase Common Stock
Class Of Stock [Line Items]
Total available for future issuance	1,881,081
Conversion Feature Related To Outstanding Term Loan
Class Of Stock [Line Items]
Total available for future issuance	590,816

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-Based Compensation - Summary of Restricted Stock and Performance Stock Unit Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Restricted Stock Units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding, Beginning Balance	645,986
Granted	379,075
Vested	(334,688)
Canceled	(1,991)
Outstanding, Ending Balance	688,382
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value Outstanding, Beginning Balance	$ 10.72	$ 5.43
Weighted Average Grant Date Fair Value Outstanding, Granted	15.02
Weighted Average Grant Date Fair Value Outstanding, Vested	5.36
Weighted Average Grant Date Fair Value Outstanding, Canceled	11.8
Weighted Average Grant Date Fair Value Outstanding, Ending Balance	$ 10.72
Performance Stock Units (PSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding, Beginning Balance	449,752
Vested	(150,584)
Outstanding, Ending Balance	299,168
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value Outstanding, Beginning Balance	$ 5.96	$ 6.25
Weighted Average Grant Date Fair Value Outstanding, Vested	6.82
Weighted Average Grant Date Fair Value Outstanding, Ending Balance	$ 5.96

Consolidated Balance Sheet Components - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 13,017	$ 6,499
Accrued employee and related expenses	6,248	4,165
Accrued professional and legal fees	1,110	1,052
Accrued other expenses	155	228
Total accrued expenses	$ 20,530	$ 11,944

Income Taxes - Summary of Statutory Tax Rates Applicable to Income of Company and Subsidiaries (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Line Items]
Effective income tax rate	21.00%	21.00%	21.00%
89Bio Ltd
Income Tax Disclosure [Line Items]
Effective income tax rate	23.00%	23.00%	23.00%
89bio Management, Inc.
Income Tax Disclosure [Line Items]
Effective income tax rate	21.00%	21.00%	21.00%
UAB 89bio Lithuania
Income Tax Disclosure [Line Items]
Effective income tax rate	15.00%	15.00%	15.00%

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

9. Income Taxes

Tax Rates Applicable to the Income of the Company and its Subsidiaries


	Year Ended December 31,
	2023			2022			2021
89bio, Inc.		21	%		21	%		21	%
89Bio Ltd.		23	%		23	%		23	%
89bio Management, Inc.		21	%		21	%		21	%
UAB 89bio Lithuania		15	%		15	%		15	%

The income tax (expense) benefit for the periods presented is comprised of (in thousands):


				Year Ended December 31,
	2023			2022			2021
Current:
Federal	$	—		$	—		$	—
State	—				(3	)		(2	)
Foreign		(3,740	)		(16	)		(1	)
Total current		(3,740	)		(19	)		(3	)
Deferred:
Federal	—			—				150
State	—			—			—
Foreign		(127	)	—			—
Total deferred		(127	)	—				150
Income tax (expense) benefit	$	(3,867	)	$	(19	)	$	147

Deferred Income Taxes

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s deferred tax assets for the periods presented were as follows (in thousands):


	As of December 31,
	2023			2022
U.S. net operating loss carryforwards	$	62,873		$	45,002
Research and development expenses		41,834			18,927
Israel net operating loss carryforwards		—			7,385
Stock-based compensation		2,924			4,328
Accrued expenses		307			317
Operating lease liabilities		629			98
Other		378			244
Gross deferred tax assets		108,945			76,301
Less: valuation allowance		(108,230	)		(75,982	)
Total deferred tax assets	$	715		$	319

Operating lease right-of-use assets		(623	)		(100	)
Total deferred tax liabilities		(623	)		(100	)
Net deferred tax assets		92			219

As of December 31, 2023 and 2022, the Company recorded a valuation allowance of $108.2 million and $76.0 million, respectively, in respect of deferred tax assets resulting from tax loss carryforwards and other temporary differences. Realization of deferred tax assets is dependent upon future earnings, if any, the time and amount of which are uncertain. The Company regularly assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes based upon the weight of available evidence that it is more likely than not that all or a portion of deferred tax assets will not be realized, a valuation allowance is established through an adjustment to income tax expense. The valuation allowance increased by $32.2 million in 2023, which primarily relates to significant taxable losses.

Available Carryforward Tax Losses and Credits

As of December 31, 2023, the Company had an accumulated tax loss carryforward of approximately $195.0 million, $302.8 million, and $30.4 million for federal, state and Israeli tax purposes, respectively. As of December 31, 2022, the Company had an accumulated tax loss carryforward of approximately $160.9 million, $169.8 million, and $32.1 million for federal, state and Israeli tax purposes, respectively. Federal net operating losses generated after 2017 can be carried forward indefinitely but utilization will be limited to 80% of taxable income in the period that net operating losses are being utilized. Carryforward tax losses in California will begin to expire in 2039. Carryforward tax losses in Israel have no expiration date.

As of December 31, 2023 and 2022, the Company had federal research and development credit carryforwards of approximately $7.5 million and $4.3 million, respectively, which expire beginning in 2040. As of December 31, 2023 and 2022, the Company had state research and development credit carryforwards of approximately $3.2 million and $1.8 million, respectively, which will carry forward indefinitely.

Loss from Operations, Before Income Tax

The Company recorded a loss from operations, before income tax for the periods presented as follows (in thousands):


	Year Ended December 31,
	2023			2022			2021
United States	$	(138,293	)	$	(101,938	)	$	(91,141	)
Lithuania		(59	)		(7	)		10
Israel		30			(62	)		862
Net loss before income tax	$	(138,322	)	$	(102,007	)	$	(90,269	)

Reconciliation of Income Tax (Expense) Benefit

The reconciliation of income tax (expense) benefit based on the statutory tax rate to the effective tax rate for the periods presented is as follows (in thousands):


	Year Ended December 31,
	2023			2022			2021
Income tax benefit computed at statutory rates	$	29,054		$	21,429		$	18,757
Change in valuation allowance		(32,248	)		(33,936	)		(20,111	)
Foreign rate differential		(2	)		1			(19	)
State income taxes, net of federal benefit		7,653			5,824			—
State deferred tax true-up due to change in apportionment		2,030			6,517			—
Unrecognized tax benefits		(9,940	)		—			—
Research and development credits, net of uncertain tax position		3,275			2,130			1,331
Executive compensation limitation		(3,971	)		—			—
Other		282			(1,984	)		189
Income tax (expense) benefit	$	(3,867	)	$	(19	)	$	147

Utilization of U.S. federal and state net operating losses and credit carryforwards may be subject to an annual limitation provided for in Section 382 of the Internal Revenue Code and similar state codes. Any annual limitation could result in a deferral of the utilization of the net operating loss and credit carryforwards.

Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of gross unrecognized tax benefits for the years ended December 31, 2023, 2022 and 2021 is as follows (in thousands):


	As of December 31,
	2023		2022			2021
Balance beginning of year		1,584		851			329
Increase (decrease) related to prior year positions		9,351		(19	)		(35	)
Increase related to current year positions		1,163		752			557
Balance end of year		12,098		1,584			851

The Company’s unrecognized tax benefits, exclusive of interest, totaled $12.1 million at December 31, 2023, of which $3.1 million, if recognized, would reduce income tax expense. A material portion of the Company’s gross unrecognized tax benefits, if recognized, would increase the Company’s net operating loss carryforward and would not have an impact to the effective tax rate as it would be offset by a full valuation allowance. For the year ended December 31, 2023, the amount of gross unrecognized tax benefits related to prior year tax positions increased by $9.4 million. The increase relates primarily to unresolved issues associated with tax returns for tax years 2018 through 2021 being audited by the Israel Tax Authority (“ITA”). In December 2023, the Company received a primary assessment from the ITA related to the Company’s 2019 reorganization and intercompany transaction to license the intellectual property rights from the Company’s Israeli subsidiary. The ITA has alleged that the transaction is deemed to be a sale of intellectual property rights. Although management believes that the Company has adequately accounted for its uncertain tax positions, the ultimate resolution of the ITA audit may result in payments that are materially different from what was originally recognized in the Company’s financial statements. The Company does not expect a resolution to this matter to be finalized within the next 12 months. Based on the information currently available, the Company does not anticipate significant increases or decreases to unrecognized tax benefits in the next twelve months. However, it is possible that such increases or decreases may occur.

The Company classifies interest and penalties related to uncertain tax positions as income tax expense. As of December 31, 2023, the interest related to uncertain tax positions was approximately $0.6 million.

The Company is subject to taxation in the United States, California, Colorado, Indiana, Maryland, North Carolina, New Jersey, Virginia and certain foreign jurisdictions. To date, the Company has not been subject to any federal or state income tax audits. As of December 31, 2023, all tax years remain open to examination.

The Tax Cuts and Jobs Act included a change in the treatment of research and development (“R&D”) expenditures for tax purposes under Section 174. Effective for tax years beginning after December 31, 2021, specified R&D expenditures must undergo a five-year amortization period for domestic spend and a 15-year amortization period for foreign spend. Prior to the effective date (2021 tax year and prior), taxpayers were able to immediately expense R&D costs under Section 174(a) or had the option to capitalize and amortize R&D expenditures over a five-year recovery period under Section 174(b). The Company has evaluated the current legislation at this time and prepared the provision by following the treatment of R&D expenditures for tax purposes under Section 174.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Section S99
-Paragraph 1
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-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Aggregated Fair Value	$ 361,302
Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	361,117	$ 181,807
Short-term investments, Gross Unrealized Holding Gains	439	12
Short-term investments, Gross Unrealized Holding Losses	(254)	(374)
Short-term investments, Aggregated Fair Value	361,302	181,445
Recurring \| Cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Aggregated Fair Value	98,593	48,540
Recurring \| Marketable Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Aggregated Fair Value	262,709	132,905
Recurring \| Level 1 \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	493	18,224
Short-term investments, Aggregated Fair Value	493	18,224
Recurring \| Level 2 \| Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	94,261	104,279
Short-term investments, Gross Unrealized Holding Gains		1
Short-term investments, Gross Unrealized Holding Losses	(55)	(84)
Short-term investments, Aggregated Fair Value	94,206	104,196
Recurring \| Level 2 \| U.S. government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	137,976	18,225
Short-term investments, Gross Unrealized Holding Gains	250	1
Short-term investments, Gross Unrealized Holding Losses	(142)	(109)
Short-term investments, Aggregated Fair Value	138,084	18,117
Recurring \| Level 2 \| Agency bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	45,481	13,986
Short-term investments, Gross Unrealized Holding Gains	152
Short-term investments, Gross Unrealized Holding Losses	(44)	(78)
Short-term investments, Aggregated Fair Value	45,589	13,908
Recurring \| Level 2 \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	3,177	10,488
Short-term investments, Gross Unrealized Holding Losses	(12)	(62)
Short-term investments, Aggregated Fair Value	3,165	10,426
Recurring \| Level 2 \| U.S. Treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	71,754	7,414
Short-term investments, Gross Unrealized Holding Gains	36	1
Short-term investments, Gross Unrealized Holding Losses	(1)	(21)
Short-term investments, Aggregated Fair Value	71,789	7,394
Recurring \| Level 2 \| Non-US debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost		3,975
Short-term investments, Gross Unrealized Holding Losses		(20)
Short-term investments, Aggregated Fair Value		3,955
Recurring \| Level 2 \| Agency discount securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments, Amortized Cost	7,975	5,216
Short-term investments, Gross Unrealized Holding Gains	1	9
Short-term investments, Gross Unrealized Holding Losses		0
Short-term investments, Aggregated Fair Value	$ 7,976	$ 5,225

Net Loss Per Share - Schedule of Outstanding Potentially Dilutive Securities Excluded From Calculation of Diluted Net Loss (Details) - shares

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

Dec. 31, 2021

Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]

Antidilutive common stock equivalents excluded from calculation of diluted net loss per share

16,677,749

17,423,938

2,571,985

Employee Stock Option

Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]

Antidilutive common stock equivalents excluded from calculation of diluted net loss per share

4,686,577

3,161,917

2,406,668

RSUs and PSUs Outstanding

Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]

Antidilutive common stock equivalents excluded from calculation of diluted net loss per share

987,550

1,095,738

106,394

Warrants to Purchase Common Stock Outstanding

Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]

Antidilutive common stock equivalents excluded from calculation of diluted net loss per share

^[1]

10,412,806

13,166,283

58,923

Conversion Feature Related To Outstanding Term Loan

Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]

Antidilutive common stock equivalents excluded from calculation of diluted net loss per share

590,816

[1]	Excludes pre-funded warrants to purchase 1,881,081 common shares as they are required to be included in basic and diluted net loss per share.

Term Loan Facilities

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Term Loan Facilities

6. Term Loan Facilities

2021 Loan Agreement

In April 2020, the Company entered into a Loan and Security Agreement, (the “Loan Agreement”) with the lenders referred to therein, and Silicon Valley Bank (“SVB”), as collateral agent. The Loan Agreement as amended in May 2021 (the “2021 Loan Agreement”) provided for (i) a secured term A loan facility (the “Term A Loan Facility”) of up to $20.0 million and (ii) a secured term B loan facility (the “Term B Loan Facility”) of up to $5.0 million. The Term A Loan Facility of $20.0 million was fully drawn as of December 2022 and the Term B Loan Facility expired undrawn.

In January 2023, the Company executed a loan and security agreement with new lenders (the “2023 Loan Agreement”) and used the borrowings to repay in full the outstanding principal, final payment fee, prepayment fee and interest due under the 2021 Loan Agreement of $21.4 million. The Company recorded a loss on debt extinguishment of $1.2 million, which was recognized as a component of interest expense on the Company’s consolidated statements of operations and comprehensive loss.

2023 Loan Agreement

In January 2023, the Company executed the 2023 Loan Agreement with the lenders referred to therein, K2 HealthVentures LLC (“K2HV”) as administrative agent and Ankura Trust Company, LLC as collateral agent. The

2023 Loan Agreement provides for up to $100.0 million in aggregate principal in term loans, consisting of an initial tranche of $25.0 million that was funded at closing, second and third tranches of $15.0 million and $10.0 million, respectively, that may be funded upon the achievement of certain time-based, clinical and regulatory milestones, and a fourth tranche of up to $50.0 million that may be funded upon discretionary approval by the lenders. As of December 31, 2023, the second tranche of $15.0 million expired undrawn.

Borrowings under term loans are secured by substantially all of the assets of the Company, excluding the Company’s intellectual property. The 2023 Loan Agreement contains customary representations and warranties, restricts certain activities and includes customary events of default, including payment default, breach of covenants, change of control, and material adverse effects. In addition, starting January 1, 2024, the Company is required to maintain minimum unrestricted cash and cash equivalents equal to 5.0 times the average change in cash and cash equivalents measured over the trailing three-month period.

Borrowings under the term loan facility mature on January 1, 2027 and provide for interest-only payments until February 1, 2025. Consecutive equal payments of principal and interest are due once the interest-only period has elapsed. The term loans bear interest equal to the greater of (i) 8.45% and (ii) the sum of (a) the Prime Rate as reported in The Wall Street Journal plus (b) 2.25%. The interest rate on the first term loan was 9.75% at inception and 10.75% as of December 31, 2023. In addition, a final payment fee equal to 5.95% of the principal amount of the term loans is due upon the earlier of prepayment or maturity of the term loans. The Company has the option to prepay the entire outstanding balance of the term loans subject to a prepayment fee ranging from 1.0% to 3.0% depending on the timing and circumstances of such prepayment. A commitment fee equal to 0.6% of the principal amount of the fourth term loan is also payable if drawn.

K2HV has an option to convert up to an aggregate of $7.5 million of the principal amount of the term loans then outstanding into shares of the Company’s common stock at a conversion price of $12.6943 per share at any time prior to full repayment of the term loans. This embedded conversion option qualifies for a scope exception from derivative accounting because it is both indexed to the Company’s own stock and meets the conditions for equity classification.

Total debt issuance costs related to the first term loan of $0.8 million, which includes the fair value of the warrant that became exercisable as a result of the funding of the first term loan (discussed below), were recorded as debt discount. The debt discount, together with the final payment fee, are recognized as interest expense using the effective interest method. For the year ended December 31, 2023, the weighted-average effective interest rate on outstanding borrowings under the 2023 Loan Agreement was approximately 13.3%.

As of December 31, 2023, the Company’s maturities of principal obligations under the term loan were as follows (in thousands):


2024	$	—
2025		10,774
2026		13,036
2027		1,190
Total principal outstanding		25,000
Plus accumulated accretion of final payment fee		388
Less unamortized debt discount		(593	)
Total net carry value		24,795
Term loan, current portion		—
Term loan, non-current, net	$	24,795

Warrants

In January 2023, in connection with the 2023 Loan Agreement, the Company issued the lenders a warrant to purchase up to an aggregate of 204,815 shares of the Company’s common stock at an exercise price of $9.7649 per share (the “warrant shares”) that expires in January 2033. The warrant shares become exercisable upon the funding of each term loan. In connection with the first term loan that was funded at closing, 51,204 of the warrant shares became exercisable. The warrant shares cannot be settled for cash and include a cashless exercise feature allowing

the holder to receive shares net of shares withheld in lieu of the exercise price. The warrant shares also provide for automatic cashless exercise under certain specific conditions and settlement is permitted in unregistered shares. The 51,204 warrant shares meet the requirements for equity classification.

The Company determined the fair value of the 51,204 warrant shares issued using the Black-Scholes option-pricing model with the following assumptions: risk-free interest rate of 3.9%, no dividends, expected volatility of 93.8% and expected term of 10.0 years.

Of the remaining 153,611 warrant shares (the “contingent warrants”), 122,889 warrant shares are contingently exercisable upon the funding of each subsequent term loan drawn and have the same exercise price and contractual term and 30,722 warrant shares associated with the second term loan facility expired on September 30, 2023. The contingent warrants did not meet the derivative scope exception or equity classification criteria and were accounted for as a derivative liability. The contingent warrants’ initial fair value and fair value as of December 31, 2023, determined using a probability weighted Black-Scholes option pricing model, was insignificant. The contingent warrants derivative liability is remeasured at each reporting period until settled or extinguished with subsequent changes in fair value recorded as interest expense in the consolidated statements of operations and comprehensive loss.

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Schedule of Shares of Common Stock Available for Future Issuance

As of December 31, 2023, common stock reserved for future issuance, on an as-if-converted basis, were as follows:


Stock options outstanding			4,686,577
RSUs and PSUs outstanding			987,550
Shares available for future grants under equity incentive plans			1,790,684
Shares available for future issuance under the employee stock purchase plan			1,207,607
Warrants to purchase common stock outstanding			10,412,806
Pre-funded warrants to purchase common stock outstanding			1,881,081
Conversion feature related to outstanding term loan			590,816
Total shares of common stock reserved			21,557,121

Schedule of Outstanding Warrants to Purchase Shares of Common Stock

As of December 31, 2023, the Company’s outstanding warrants to purchase shares of its common stock were as follows:


	Shares of Common Stock Underlying Warrants		Exercise Price Per Share		Expiration Date
Warrant issued in connection with term loan (SVB)		25,000	$	22.06	June 30, 2025
Warrant issued in connection with term loan (SVB)		33,923	$	19.12	May 28, 2031
Warrants issued in connection with term loan facility (K2HV)		174,093	$	9.76	January 27, 2033
Warrants issued in public offering		10,179,790	$	5.325	July 1, 2024
Pre-funded warrants issued in public offerings		1,881,081	$	0.001	Do not expire
Total outstanding		12,293,887

Term Loan Facilities - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended			12 Months Ended
	Jan. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($)	Apr. 30, 2020 USD ($)	Dec. 31, 2023 USD ($) shares
Debt Instrument [Line Items]
Loss on extinguishment				$ (1,208)
Debt discount				$ 593
Tranche One
Debt Instrument [Line Items]
Warrants to purchase common stock \| shares	51,204
Loan Agreement
Debt Instrument [Line Items]
Line of credit facility, description			In April 2020, the Company entered into a Loan and Security Agreement, (the “Loan Agreement”) with the lenders referred to therein, and Silicon Valley Bank (“SVB”), as collateral agent. The Loan Agreement as amended in May 2021 (the “2021 Loan Agreement”) provided for (i) a secured term A loan facility (the “Term A Loan Facility”) of up to $20.0 million and (ii) a secured term B loan facility (the “Term B Loan Facility”) of up to $5.0 million. The Term A Loan Facility of $20.0 million was fully drawn as of December 2022 and the Term B Loan Facility expired undrawn.
Loan Agreement \| Term A Loan Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 20,000
Line of credit facility fully drawn amount		$ 20,000
Loan Agreement \| Term B Loan Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 5,000
2023 Loan Agreement
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 100,000
Line of credit facility, description	In January 2023, the Company executed a loan and security agreement with new lenders (the “2023 Loan Agreement”) and used the borrowings to repay in full the outstanding principal, final payment fee, prepayment fee and interest due under the 2021 Loan Agreement of $21.4 million. The Company recorded a loss on debt extinguishment of $1.2 million, which was recognized as a component of interest expense on the Company’s consolidated statements of operations and comprehensive loss.
Warrant exercise price \| $ / shares	$ 9.7649
Warrant expiration date				Sep. 30, 2023
Minimum unrestriced cash and cash equivalents to three month average cash and cash equivalents multiplier				5
Debt instrument, maturity date, description				Borrowings under the term loan facility mature on January 1, 2027 and provide for interest-only payments until February 1, 2025.
Debt instrument, maturity date				Jan. 01, 2027
Warrants expiration month and year	2033-01
Debt instrument, interest rate	9.75%			10.75%
Debt instrument, basis spread on variable rate	2.25%
Percentage of fee on loan				5.95%
Conversion price per share \| $ / shares	$ 12.6943
Contingent warrants \| shares	153,611
Warrant Forfeited \| shares				30,722
2023 Loan Agreement \| Maximum
Debt Instrument [Line Items]
Warrants to purchase common stock \| shares	204,815
Prepayment fee percentage				3.00%
Conversion of principal amount	$ 7,500
2023 Loan Agreement \| Minimum
Debt Instrument [Line Items]
Debt instrument, interest rate	8.45%
Debt instrument, effective interest rate				13.30%
Prepayment fee percentage				1.00%
2023 Loan Agreement \| Tranche One
Debt Instrument [Line Items]
Line of credit facility fully drawn amount	$ 25,000
Debt discount	800
2023 Loan Agreement \| Tranche One \| Measurement Input, Expected Dividend Payment
Debt Instrument [Line Items]
Fair value of warrant assumptions, dividends	$ 0
2023 Loan Agreement \| Tranche One \| Valuation Technique, Option Pricing Model \| Measurement Input, Risk Free Interest Rate
Debt Instrument [Line Items]
Fair measurement input	0.039
2023 Loan Agreement \| Tranche One \| Valuation Technique, Option Pricing Model \| Measurement Input, Price Volatility
Debt Instrument [Line Items]
Fair measurement input	0.938
2023 Loan Agreement \| Tranche One \| Valuation Technique, Option Pricing Model \| Measurement Input, Expected Term
Debt Instrument [Line Items]
Fair measurement input	10 years
2023 Loan Agreement \| Tranche Two
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 15,000
Credit facility maturity date				Dec. 31, 2023
Line of credit facility, expired unused				$ 15,000
Warrant contingently exercisable upon funding of each subsequent term loan \| shares				122,889
2023 Loan Agreement \| Tranche Three
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	10,000
2023 Loan Agreement \| Tranche Four
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	50,000
Commitment fee percentage				0.60%
2021 Loan Agreement
Debt Instrument [Line Items]
Repaid line of credit	$ 21,400

Stock-Based Compensation - Summary of Estimated Fair Value of Stock Options Granted Using Black-Scholes Option-Pricing Model (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant date fair value	$ 11.43	$ 3.38	$ 16.18
Expected volatility, minimum	91.50%	89.90%	86.90%
Expected volatility, maximum	99.20%	91.00%	91.90%
Risk-free interest rate, minimum	3.40%	1.60%	0.70%
Risk-free interest rate, maximum	4.60%	3.90%	1.30%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	5 years 6 months	5 years 6 months	5 years 6 months
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	6 years 1 month 6 days	6 years 3 months 18 days	6 years 1 month 6 days

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Paragraph 1D
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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+ Details

Term Loan Facilities - Schedule of Maturities of Principal Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
2024	$ 0
2025	10,774
2026	13,036
2027	1,190
Total principal outstanding	25,000
Plus accumulated accretion of final payment fee	388
Less unamortized debt discount	(593)
Long-Term Debt, Total	24,795
Term loan, current portion	0
Term loan, non-current, net	$ 24,795	$ 20,192

Consolidated Balance Sheet Components

12 Months Ended

Dec. 31, 2023

Balance Sheet Related Disclosures [Abstract]

Consolidated Balance Sheet Components

4. Consolidated Balance Sheet Components

Prepaid and other current assets consist of the following as of the periods presented (in thousands):


	As of December 31,
	2023		2022
Prepaid research and development	$	11,579	$	5,727
Prepaid taxes		614		646
Prepaid other		2,471		1,547
Total prepaid and other current assets	$	14,664	$	7,920

Accrued expenses consist of the following as of the periods presented (in thousands):


	As of December 31,
	2023		2022
Accrued research and development expenses	$	13,017	$	6,499
Accrued employee and related expenses		6,248		4,165
Accrued professional and legal fees		1,110		1,052
Accrued other expenses		155		228
Total accrued expenses	$	20,530	$	11,944

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”).
Reclassification	Reclassifications Certain reclassifications of previously reported amounts have been made to conform to the current year presentation. Specifically, the final payment fee of $0.5 million related to borrowings under the Company’s 2021 Loan Agreement (see Note 6) was previously presented separately from “Term loan, non-current, net” under the caption “Other non-current liability” in the Form 10-K as of December 31, 2022. These captions have been combined in the consolidated balance sheet as of December 31, 2022 included within these financial statements.
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include but are not limited to accruals for uncertain tax positions, accrued research and development expenses and the valuation of stock options. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.
Foreign Currencies	Foreign Currencies The Company engages in foreign-currency-denominated transactions with certain vendors, as well as between subsidiaries with different functional currencies. The Company’s subsidiary in Israel uses the U.S. dollar as its functional currency for financial reporting. Gains and losses from foreign-currency-denominated transactions, primarily denominated in New Israeli Shekels, were not material for all periods presented and are reflected in the consolidated statements of operations and comprehensive loss as a component of interest income and other, net. The Company’s subsidiary in Lithuania uses the Euro as its functional currency for financial reporting. The re-measurement from Euros to U.S. dollars results in translation gain and loss adjustments, which are included in the consolidated balance sheets as part of accumulated other comprehensive loss.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. Assets and liabilities recorded at fair value are categorized based upon the level of judgment associated with the inputs used to measure their fair value. Hierarchical levels are directly related to the amount of subjectivity with the inputs to the valuation of these assets or liabilities as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable inputs for similar assets or liabilities. These include quoted prices for identical or similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active; and Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Assets Measured at Fair Value on a Recurring Basis As of December 31, 2023 and 2022, marketable securities were the only financial instruments measured and recorded at fair value on a recurring basis on the Company’s consolidated balance sheets. Financial Instruments Not Carried at Fair Value The Company’s financial instruments, including cash, other current assets, accounts payable and accrued expenses are carried at cost which approximates their fair value because of the short-term nature of these financial instruments. The fair value of the Company’s term loan approximates its carrying value, or amortized cost, due to the prevailing market rates of interest it bears.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash, cash equivalents and marketable securities. Bank deposits are held by accredited financial institutions and these deposits may at times be in excess of insured limits. The Company limits its credit risk associated with cash and cash equivalents by placing them with financial institutions that it believes are of high quality. The Company has not experienced any losses on its deposits of cash or cash equivalents. The Company has established guidelines relative to diversification and maturities to maintain safety and liquidity and limits amounts invested in marketable securities by credit rating, maturity, industry group, investment type and issuer, except for securities issued by the U.S. government. The Company does not believe a significant risk of loss from a concentration of credit risk exists with respect to its marketable securities portfolio.
Other Risks and Uncertainties	Other Risks and Uncertainties The Company’s future results of operations involve a number of other risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the Company’s early stages of clinical drug development; the Company’s ability to advance product candidates into, and successfully complete, clinical trials on the timelines it projects; the Company’s ability to adequately demonstrate sufficient safety and efficacy of its product candidates; the Company’s ability to enroll patients in its ongoing and future clinical trials; the Company’s ability to successfully manufacture and supply its product candidates for clinical trials; the Company’s ability to obtain additional capital to finance its operations; uncertainties related to the projections of the size of patient populations suffering from the diseases the Company is targeting; the Company’s ability to obtain, maintain, and protect its intellectual property rights; developments relating to the Company’s competitors and its industry, including competing product candidates and therapies; general economic and market conditions; and other risks and uncertainties. The Company’s product candidates will require approvals from the U.S. Food and Drug Administration and comparable foreign regulatory agencies prior to commercial sales in their respective jurisdictions. There can be no assurance that any product candidates will receive the necessary approvals. If the Company is denied approval, approval is delayed or the Company is unable to maintain approval for any product candidate, it could have a materially adverse impact on the Company.
Segment Reporting	Segment Reporting Operating segments are defined as components of an enterprise that have the following characteristics: (i) they engage in business activities from which they may earn revenue and incur expense, (ii) their operating results are regularly reviewed by the chief operating decision maker (“CODM”) for resource allocation decisions and performance assessment, and (iii) their discrete financial information is available. The Company’s CODM is its Chief Executive Officer. The Company and the CODM view the Company’s operations and manage its business in one operating segment.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly-liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents primarily consist of amounts invested in money market funds, commercial paper and U.S. government treasury securities and are carried at fair value.
Marketable Securities	Marketable Securities The Company invests its excess cash in marketable securities with high credit ratings including money market funds, commercial paper, securities issued by the U.S. government and its agencies and corporate debt securities. The Company accounts for all marketable securities as available-for-sale, as the sale of such securities may be required prior to maturity. These marketable securities are carried at fair value, with unrealized gains and losses reported as accumulated other comprehensive income (loss) until realized. The cost of debt securities is adjusted for accretion of premiums and amortization of discounts to maturity. Such amortization and accretion, as well as interest and dividends, are included in interest income and other, net. Realized gains and losses from the sale of available-for-sale securities, if any, are determined on a specific identification basis and are also included in interest income and other, net. The Company’s marketable securities are classified as current assets, which reflects management’s intention to use the proceeds from sales of these securities to fund its operations, as necessary, even though the stated maturity date may be one year or more beyond the current balance sheet date. The Company periodically assesses its available-for-sale marketable securities for impairment. For marketable securities in an unrealized loss position, this assessment first takes into account the Company’s intent to sell, or whether it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of these criteria are met, the marketable security’s amortized cost basis is written down to fair value through interest income and other, net. For marketable securities in an unrealized loss position that do not meet the aforementioned criteria, the Company assesses whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and any adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss may exist, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses will be recorded in interest income and other, net, limited by the amount that the fair value is less than the amortized cost basis. Any additional impairment not recorded through an allowance for credit losses is recognized in other comprehensive loss. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the allowance when management believes the uncollectability of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. These changes are recorded in interest income and other, net.
Leases	Leases The Company has noncancellable operating leases for office space. Beginning in 2022, the Company accounts for leases in accordance with Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842). The Company determines if an arrangement is a lease or contains an embedded lease at inception. The Company accounts for a contract as a lease when it has the right to control the asset for a period of time while obtaining substantially all of the asset’s economic benefits. For arrangements that meet the definition of a lease, the Company determines the initial classification and measurement of its right-of-use (“ROU”) asset and lease liability at the lease commencement date and thereafter if modified. Operating lease ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make the contractual lease payments over the lease term. The ROU asset is initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. The operating lease liability is initially measured at the present value of the unpaid lease payments at the lease commencement date. The lease liability is subsequently measured at amortized cost using the effective-interest method. The lease term includes any renewal options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its estimated collateralized incremental borrowing rate that the Company would pay for a similar amount and term. The Company has elected not to record leases with an original term of twelve months or less on its consolidated balance sheets. The Company does not have any material short-term leases. In addition, the Company’s leases may require the Company to pay additional costs, such as utilities, maintenance, and other operating costs, which are generally referred to as non-lease components and vary based on future outcomes. The Company has elected to not separate lease and non-lease components. Only the fixed costs for lease components and their associated non-lease components are accounted for as a single lease component and recognized as part of a ROU asset and lease liability. Any variable expenses are recognized in operating expenses as incurred. Lease expense for an operating lease liability is recognized on a straight-line basis over the lease term and is included in operating expenses in the consolidated statements of operations and comprehensive loss.
Property and Equipment, Net	Property and Equipment, Net Property and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful lives of the related assets, generally ranging from three to seven years. Leasehold improvements are amortized on a straight-line basis over the shorter of the assets’ estimated useful life or the remaining term of the lease. Upon retirement or sale of the assets, the cost and related accumulated depreciation and amortization are removed from the consolidated balance sheets and the resulting gains or losses are recorded in the consolidated statements of operations and comprehensive loss. Maintenance and repair costs are expensed as incurred.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company periodically evaluates its long-lived assets, including property and equipment, for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets or group of assets may not be fully recoverable. If indicators of impairment exist and the undiscounted future cash flows that the assets are expected to generate are less than the carrying value of the assets, then the Company will reduce the carrying amount of the assets through an impairment charge, to their estimated fair values based on a discounted cash flow approach or, when available and appropriate, to comparable market values. There were no such indicators for the periods presented.
Accrued Research and Development Expenses	Accrued Research and Development Expenses The Company records preclinical and clinical study and research expenses based on the services performed, pursuant to contracts with research institutions that conduct and manage preclinical and clinical studies and research services on its behalf. The majority of these expenses are recorded based on invoices and statements received from these vendors. The Company also records these expenses based upon the estimated services provided but not yet invoiced. Liabilities associated with these expenses are included in accrued expenses in the consolidated balance sheets. These costs are a component of the Company’s research and development expenses. In making these estimates of services provided but not yet invoiced or for which statements have not been received from vendors, the Company considers factors such as estimates of the progress of work completed in accordance with agreements established with its third-party service providers. As actual costs become known, the Company adjusts its accrued expenses. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accrued expenses could materially affect the Company’s results of operations. Contingent milestone payments, if any, are recognized when payment becomes probable and reasonably estimable, which is generally upon achievement of the milestone.
Warrants To Purchase Common Stock	Warrants to Purchase Common Stock The Company classifies warrants indexed to its common stock and meeting the requirements for equity classification within stockholders’ equity. This assessment is conducted at the time of warrant issuance and as of each reporting period that the warrants remain outstanding.
Research and Development Expenses	Research and Development Expenses Research and development expenses consist primarily of costs incurred for the development of the Company’s lead product candidate, pegozafermin. Research and development expenses consist primarily of external costs related to preclinical and clinical development and related supplies and personnel costs. Personnel costs consist of salaries, employee benefits and stock-based compensation for individuals involved in research and development efforts. Payments associated with agreements to acquire licenses to develop, use, manufacture and commercialize products and purchases of pegozafermin from contract manufacturing organizations that have not reached technological feasibility and do not have alternate future commercial use are expensed as incurred.
Stock-Based Compensation	Stock-Based Compensation The Company utilizes stock options, restricted stock units (“RSUs”) and performance stock units (“PSUs”) for equity compensation. The Company measures its equity awards made to employees, directors, and non-employee service providers based on estimated fair values and recognizes stock-based compensation over the requisite service period. The Company accounts for forfeitures as they occur. The Company estimates the fair value of stock option awards on the date of grant using a Black-Scholes option pricing model. The Company recognizes compensation for stock option awards, including awards with graded-vesting, on a straight-line basis over the requisite service period. The Black-Scholes option pricing model requires a number of assumptions, of which the most significant are expected volatility, expected option term (the time from the grant date until the options are exercised or expire), risk-free rate, and expected dividend rate. These assumptions include: • Expected volatility—The Company has a limited trading history for its common stock. As a result, the Company estimates expected volatility based on a combination of its own historical stock price volatility and that of a publicly traded set of peer companies such that the time period over which historical volatility data used is at least equal to the expected term of the option award. The peer companies were chosen based on their similar size, stage in the life cycle, or area of specialty. • Expected term—The expected term of options granted to employees and directors is determined using the “simplified” method. Under this approach, the expected term is presumed to be the midpoint between the weighted-average vesting term and the contractual term of the option. The simplified method makes the assumption that the employee will exercise stock options evenly over the period when the stock options are vested and ending on the date when the stock options would expire. The expected option term for options granted to non-employees is estimated on a grant-by-grant basis. • Risk-free interest rate—The risk-free interest rate is based on the U.S. Treasury zero coupon bonds in effect on the grant date for periods with an equivalent expected term as the option. • Expected dividend—The Company has never paid dividends and has no foreseeable plans to pay dividends on its shares of common stock. Therefore, an expected dividend of zero is used. The grant date fair value of RSUs and PSUs are based on the closing price of the Company’s common stock on the date of grant. RSUs are service-based awards and are recognized over the requisite service period on a straight-line basis. Compensation expense for PSUs is recognized over the estimated service period for each tranche of an award (the accelerated attribution method) when its performance condition is deemed probable of achievement. For PSUs containing performance conditions which were not deemed probable of achievement, no stock compensation expense is recognized. Additionally, at each reporting period, the Company evaluates the probable outcome of the performance conditions and as applicable, recognizes the cumulative effect of the change in estimate in the period of the change.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the consolidated financial statements carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized as income or loss in the period that includes the enactment date. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company has established full valuation allowances on its U.S. deferred tax assets because realization of these tax benefits through future taxable income is not more likely than not as of December 31, 2023 and 2022. The Company intends to maintain the valuation allowances until sufficient positive evidence exists to support the reversal of the valuation allowances. The calculation of the Company’s accruals for tax contingencies involves dealing with uncertainties in the application of complex tax laws. The Company’s estimates for the potential outcome of any uncertain tax issue are based on the detailed facts and circumstances of each issue. Resolution of these uncertainties in a manner inconsistent with the Company’s expectations could have a material impact on its results of operations and financial condition. The Company recognizes liabilities for uncertain tax positions based on a two-step process. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to estimate and measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. It is inherently difficult and subjective to estimate such amounts, as this requires the Company to determine the probability of various possible outcomes. The Company reevaluates these uncertain tax positions on a quarterly basis. This evaluation is based on factors including, but not limited to, changes in facts or circumstances, changes in tax law, effectively settled issues under audit, and new audit activity. Such a change in recognition or measurement would result in the recognition of a tax benefit or an additional charge to tax expense in the period. Interest and penalties related to unrecognized tax benefits are included within income tax (expense) benefit.
Basic and Diluted Net Loss per Share	Basic and Diluted Net Loss per Share Basic and diluted net loss per share is calculated based upon the weighted-average number of shares of common stock outstanding during the period. Shares of common stock that are potentially issuable for little or no cash consideration at issuance, such as the Company’s pre-funded warrants issued in July 2022 and December 2023 are included in the calculation of basic and diluted net loss per share, even if they are antidilutive. During periods of income, participating securities are allocated a proportional share of income determined by dividing total weighted-average participating securities by the sum of the total weighted-average common shares and participating securities (the “two-class method”). Shares of the Company’s common stock warrants participate in any dividends that may be declared by the Company and are therefore considered to be participating securities. Participating securities have the effect of diluting both basic and diluted earnings per share during periods of income. During periods of loss, no loss is allocated to participating securities since they have no contractual obligation to share in the losses of the Company. Diluted loss per share is computed after giving consideration to the dilutive effect of stock options, RSUs, PSUs and common stock warrants, except where such non-participating securities would be anti-dilutive. As the Company incurred net losses for the periods presented, basic net loss per share is the same as diluted net loss per share since the effects of potentially dilutive securities are antidilutive.
Comprehensive Loss	Comprehensive Loss The Company’s comprehensive loss is comprised of net loss and changes in unrealized gains or losses on marketable securities and foreign currency translation adjustments.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40)—Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies the accounting for convertible instruments, amends the guidance on derivative scope exceptions for contracts in an entity’s own equity, and modifies the guidance on diluted earnings per share calculations as a result of these changes. The Company early adopted ASU 2020-06 as of January 1, 2023, using a modified retrospective approach and the adoption did not have a material impact on the Company’s consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which is intended to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant expenses. ASU 2023-07 requires disclosures to include significant segment expenses that are regularly provided to the CODM, a description of other segment items by reportable segment, and any additional measures of a segment's profit or loss used by the CODM when deciding how to allocate resources. The ASU also requires all annual disclosures required by Topic 280 to be included in interim periods. The ASU is effective for the Company’s annual periods beginning on January 1, 2024 and interim periods beginning on January 1, 2025. Early adoption is permitted and requires retrospective application to all prior periods presented in the financial statements. The Company is currently evaluating the effect of adopting this new accounting guidance on its financial statement disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires companies to disclose, on an annual basis, specific categories in the effective tax rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. In addition, ASU 2023-09 requires companies to disclose additional information about income taxes paid. The ASU is effective for the Company’s annual periods beginning on January 1, 2025 and will be applied on a prospective basis with the option to apply the standard retrospectively. The Company is currently evaluating the effect of adopting this new accounting guidance on its financial statement disclosures.

Consolidated Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2023

Balance Sheet Related Disclosures [Abstract]

Schedule of Prepaid and Other Current Assets

Prepaid and other current assets consist of the following as of the periods presented (in thousands):


	As of December 31,
	2023		2022
Prepaid research and development	$	11,579	$	5,727
Prepaid taxes		614		646
Prepaid other		2,471		1,547
Total prepaid and other current assets	$	14,664	$	7,920

Schedule of Accrued Expenses

Accrued expenses consist of the following as of the periods presented (in thousands):


	As of December 31,
	2023		2022
Accrued research and development expenses	$	13,017	$	6,499
Accrued employee and related expenses		6,248		4,165
Accrued professional and legal fees		1,110		1,052
Accrued other expenses		155		228
Total accrued expenses	$	20,530	$	11,944

Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Oct. 31, 2019	Sep. 30, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Feb. 28, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of stock options exercised			$ 3,200	$ 600	$ 3,600
Common stock shares reserved for future issuance			21,557,121
Unrecognized unvested stock option			$ 21,700
Unrecognized weighted average period			2 years 7 months 6 days
Compensation expense			$ 16,106	10,356	8,678
Stock Option Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense			11,700	7,600	7,500
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value, vested			$ 7,500	900	0
Unrecognized weighted average period			1 year 6 months
Compensation expense			$ 4,300	2,700	1,100
Total Unrecognised expense			5,300
Performance Stock Units (PSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value, vested			$ 7,500	900	0
Unrecognized weighted average period			1 year 6 months
Compensation expense			$ 4,300	$ 2,700	$ 1,100
Total Unrecognised expense			$ 5,300
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares issuable under the plan (in shares)	225,188
Percentage of increase in number of shares of capital stock issued and outstanding	1.00%
Percent of purchase shares of common stock	85.00%
Common stock shares reserved for future issuance			1,207,607
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, common stock issued under ESPP			27,217	18,364	10,712
2019 Plan and 2023 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares issuable under the plan (in shares)		2,844,193
Percentage of increase in number of shares of capital stock issued and outstanding		4.00%
Vesting period			4 years
Percentage of option vesting			25.00%
Terms of award			The board of directors determines the period over which options become exercisable and options generally vest over a four-year period, with 25% of options vesting on the first anniversary of employment, and thereafter, the remaining options vesting quarterly, over the following 36-month period. The options expire within ten years from the date of grant. The exercise price of awards granted will not be less than the estimated fair value of the shares on the date of grant. The 2019 Plan also permits the board of directors to grant restricted stock units, which are subject to continued service conditions.
Remaining option vesting period			36 months
Expiration period			10 years
2023 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance						1,500,000
Maximum \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
Maximum \| Performance Stock Units (PSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
Maximum \| Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Period for increase in number of shares of common stock reserved for issuance	10 years
Maximum \| 2019 Plan and 2023 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Period for increase in number of shares of common stock reserved for issuance		10 years
Minimum \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			2 years
Minimum \| Performance Stock Units (PSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”). Reclassifications Certain reclassifications of previously reported amounts have been made to conform to the current year presentation. Specifically, the final payment fee of $0.5 million related to borrowings under the Company’s 2021 Loan Agreement (see Note 6) was previously presented separately from “Term loan, non-current, net” under the caption “Other non-current liability” in the Form 10-K as of December 31, 2022. These captions have been combined in the consolidated balance sheet as of December 31, 2022 included within these financial statements. Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include but are not limited to accruals for uncertain tax positions, accrued research and development expenses and the valuation of stock options. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates. Foreign Currencies The Company engages in foreign-currency-denominated transactions with certain vendors, as well as between subsidiaries with different functional currencies. The Company’s subsidiary in Israel uses the U.S. dollar as its functional currency for financial reporting. Gains and losses from foreign-currency-denominated transactions, primarily denominated in New Israeli Shekels, were not material for all periods presented and are reflected in the consolidated statements of operations and comprehensive loss as a component of interest income and other, net. The Company’s subsidiary in Lithuania uses the Euro as its functional currency for financial reporting. The re-measurement from Euros to U.S. dollars results in translation gain and loss adjustments, which are included in the consolidated balance sheets as part of accumulated other comprehensive loss. Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. Assets and liabilities recorded at fair value are categorized based upon the level of judgment associated with the inputs used to measure their fair value. Hierarchical levels are directly related to the amount of subjectivity with the inputs to the valuation of these assets or liabilities as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable inputs for similar assets or liabilities. These include quoted prices for identical or similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active; and Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Assets Measured at Fair Value on a Recurring Basis As of December 31, 2023 and 2022, marketable securities were the only financial instruments measured and recorded at fair value on a recurring basis on the Company’s consolidated balance sheets. Financial Instruments Not Carried at Fair Value The Company’s financial instruments, including cash, other current assets, accounts payable and accrued expenses are carried at cost which approximates their fair value because of the short-term nature of these financial instruments. The fair value of the Company’s term loan approximates its carrying value, or amortized cost, due to the prevailing market rates of interest it bears. Concentrations of Credit Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash, cash equivalents and marketable securities. Bank deposits are held by accredited financial institutions and these deposits may at times be in excess of insured limits. The Company limits its credit risk associated with cash and cash equivalents by placing them with financial institutions that it believes are of high quality. The Company has not experienced any losses on its deposits of cash or cash equivalents. The Company has established guidelines relative to diversification and maturities to maintain safety and liquidity and limits amounts invested in marketable securities by credit rating, maturity, industry group, investment type and issuer, except for securities issued by the U.S. government. The Company does not believe a significant risk of loss from a concentration of credit risk exists with respect to its marketable securities portfolio. Other Risks and Uncertainties The Company’s future results of operations involve a number of other risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the Company’s early stages of clinical drug development; the Company’s ability to advance product candidates into, and successfully complete, clinical trials on the timelines it projects; the Company’s ability to adequately demonstrate sufficient safety and efficacy of its product candidates; the Company’s ability to enroll patients in its ongoing and future clinical trials; the Company’s ability to successfully manufacture and supply its product candidates for clinical trials; the Company’s ability to obtain additional capital to finance its operations; uncertainties related to the projections of the size of patient populations suffering from the diseases the Company is targeting; the Company’s ability to obtain, maintain, and protect its intellectual property rights; developments relating to the Company’s competitors and its industry, including competing product candidates and therapies; general economic and market conditions; and other risks and uncertainties. The Company’s product candidates will require approvals from the U.S. Food and Drug Administration and comparable foreign regulatory agencies prior to commercial sales in their respective jurisdictions. There can be no assurance that any product candidates will receive the necessary approvals. If the Company is denied approval, approval is delayed or the Company is unable to maintain approval for any product candidate, it could have a materially adverse impact on the Company. Segment Reporting Operating segments are defined as components of an enterprise that have the following characteristics: (i) they engage in business activities from which they may earn revenue and incur expense, (ii) their operating results are regularly reviewed by the chief operating decision maker (“CODM”) for resource allocation decisions and performance assessment, and (iii) their discrete financial information is available. The Company’s CODM is its Chief Executive Officer. The Company and the CODM view the Company’s operations and manage its business in one operating segment. Cash and Cash Equivalents The Company considers all highly-liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents primarily consist of amounts invested in money market funds, commercial paper and U.S. government treasury securities and are carried at fair value. Marketable Securities The Company invests its excess cash in marketable securities with high credit ratings including money market funds, commercial paper, securities issued by the U.S. government and its agencies and corporate debt securities. The Company accounts for all marketable securities as available-for-sale, as the sale of such securities may be required prior to maturity. These marketable securities are carried at fair value, with unrealized gains and losses reported as accumulated other comprehensive income (loss) until realized. The cost of debt securities is adjusted for accretion of premiums and amortization of discounts to maturity. Such amortization and accretion, as well as interest and dividends, are included in interest income and other, net. Realized gains and losses from the sale of available-for-sale securities, if any, are determined on a specific identification basis and are also included in interest income and other, net. The Company’s marketable securities are classified as current assets, which reflects management’s intention to use the proceeds from sales of these securities to fund its operations, as necessary, even though the stated maturity date may be one year or more beyond the current balance sheet date. The Company periodically assesses its available-for-sale marketable securities for impairment. For marketable securities in an unrealized loss position, this assessment first takes into account the Company’s intent to sell, or whether it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of these criteria are met, the marketable security’s amortized cost basis is written down to fair value through interest income and other, net. For marketable securities in an unrealized loss position that do not meet the aforementioned criteria, the Company assesses whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and any adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss may exist, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses will be recorded in interest income and other, net, limited by the amount that the fair value is less than the amortized cost basis. Any additional impairment not recorded through an allowance for credit losses is recognized in other comprehensive loss. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the allowance when management believes the uncollectability of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. These changes are recorded in interest income and other, net. Leases The Company has noncancellable operating leases for office space. Beginning in 2022, the Company accounts for leases in accordance with Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842). The Company determines if an arrangement is a lease or contains an embedded lease at inception. The Company accounts for a contract as a lease when it has the right to control the asset for a period of time while obtaining substantially all of the asset’s economic benefits. For arrangements that meet the definition of a lease, the Company determines the initial classification and measurement of its right-of-use (“ROU”) asset and lease liability at the lease commencement date and thereafter if modified. Operating lease ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make the contractual lease payments over the lease term. The ROU asset is initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. The operating lease liability is initially measured at the present value of the unpaid lease payments at the lease commencement date. The lease liability is subsequently measured at amortized cost using the effective-interest method. The lease term includes any renewal options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its estimated collateralized incremental borrowing rate that the Company would pay for a similar amount and term. The Company has elected not to record leases with an original term of twelve months or less on its consolidated balance sheets. The Company does not have any material short-term leases. In addition, the Company’s leases may require the Company to pay additional costs, such as utilities, maintenance, and other operating costs, which are generally referred to as non-lease components and vary based on future outcomes. The Company has elected to not separate lease and non-lease components. Only the fixed costs for lease components and their associated non-lease components are accounted for as a single lease component and recognized as part of a ROU asset and lease liability. Any variable expenses are recognized in operating expenses as incurred. Lease expense for an operating lease liability is recognized on a straight-line basis over the lease term and is included in operating expenses in the consolidated statements of operations and comprehensive loss. Property and Equipment, Net Property and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful lives of the related assets, generally ranging from three to seven years. Leasehold improvements are amortized on a straight-line basis over the shorter of the assets’ estimated useful life or the remaining term of the lease. Upon retirement or sale of the assets, the cost and related accumulated depreciation and amortization are removed from the consolidated balance sheets and the resulting gains or losses are recorded in the consolidated statements of operations and comprehensive loss. Maintenance and repair costs are expensed as incurred. Impairment of Long-Lived Assets The Company periodically evaluates its long-lived assets, including property and equipment, for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets or group of assets may not be fully recoverable. If indicators of impairment exist and the undiscounted future cash flows that the assets are expected to generate are less than the carrying value of the assets, then the Company will reduce the carrying amount of the assets through an impairment charge, to their estimated fair values based on a discounted cash flow approach or, when available and appropriate, to comparable market values. There were no such indicators for the periods presented. Accrued Research and Development Expenses The Company records preclinical and clinical study and research expenses based on the services performed, pursuant to contracts with research institutions that conduct and manage preclinical and clinical studies and research services on its behalf. The majority of these expenses are recorded based on invoices and statements received from these vendors. The Company also records these expenses based upon the estimated services provided but not yet invoiced. Liabilities associated with these expenses are included in accrued expenses in the consolidated balance sheets. These costs are a component of the Company’s research and development expenses. In making these estimates of services provided but not yet invoiced or for which statements have not been received from vendors, the Company considers factors such as estimates of the progress of work completed in accordance with agreements established with its third-party service providers. As actual costs become known, the Company adjusts its accrued expenses. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accrued expenses could materially affect the Company’s results of operations. Contingent milestone payments, if any, are recognized when payment becomes probable and reasonably estimable, which is generally upon achievement of the milestone. Warrants to Purchase Common Stock The Company classifies warrants indexed to its common stock and meeting the requirements for equity classification within stockholders’ equity. This assessment is conducted at the time of warrant issuance and as of each reporting period that the warrants remain outstanding. Research and Development Expenses Research and development expenses consist primarily of costs incurred for the development of the Company’s lead product candidate, pegozafermin. Research and development expenses consist primarily of external costs related to preclinical and clinical development and related supplies and personnel costs. Personnel costs consist of salaries, employee benefits and stock-based compensation for individuals involved in research and development efforts. Payments associated with agreements to acquire licenses to develop, use, manufacture and commercialize products and purchases of pegozafermin from contract manufacturing organizations that have not reached technological feasibility and do not have alternate future commercial use are expensed as incurred. Stock-Based Compensation The Company utilizes stock options, restricted stock units (“RSUs”) and performance stock units (“PSUs”) for equity compensation. The Company measures its equity awards made to employees, directors, and non-employee service providers based on estimated fair values and recognizes stock-based compensation over the requisite service period. The Company accounts for forfeitures as they occur. The Company estimates the fair value of stock option awards on the date of grant using a Black-Scholes option pricing model. The Company recognizes compensation for stock option awards, including awards with graded-vesting, on a straight-line basis over the requisite service period. The Black-Scholes option pricing model requires a number of assumptions, of which the most significant are expected volatility, expected option term (the time from the grant date until the options are exercised or expire), risk-free rate, and expected dividend rate. These assumptions include: • Expected volatility—The Company has a limited trading history for its common stock. As a result, the Company estimates expected volatility based on a combination of its own historical stock price volatility and that of a publicly traded set of peer companies such that the time period over which historical volatility data used is at least equal to the expected term of the option award. The peer companies were chosen based on their similar size, stage in the life cycle, or area of specialty. • Expected term—The expected term of options granted to employees and directors is determined using the “simplified” method. Under this approach, the expected term is presumed to be the midpoint between the weighted-average vesting term and the contractual term of the option. The simplified method makes the assumption that the employee will exercise stock options evenly over the period when the stock options are vested and ending on the date when the stock options would expire. The expected option term for options granted to non-employees is estimated on a grant-by-grant basis. • Risk-free interest rate—The risk-free interest rate is based on the U.S. Treasury zero coupon bonds in effect on the grant date for periods with an equivalent expected term as the option. • Expected dividend—The Company has never paid dividends and has no foreseeable plans to pay dividends on its shares of common stock. Therefore, an expected dividend of zero is used. The grant date fair value of RSUs and PSUs are based on the closing price of the Company’s common stock on the date of grant. RSUs are service-based awards and are recognized over the requisite service period on a straight-line basis. Compensation expense for PSUs is recognized over the estimated service period for each tranche of an award (the accelerated attribution method) when its performance condition is deemed probable of achievement. For PSUs containing performance conditions which were not deemed probable of achievement, no stock compensation expense is recognized. Additionally, at each reporting period, the Company evaluates the probable outcome of the performance conditions and as applicable, recognizes the cumulative effect of the change in estimate in the period of the change. Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the consolidated financial statements carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized as income or loss in the period that includes the enactment date. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company has established full valuation allowances on its U.S. deferred tax assets because realization of these tax benefits through future taxable income is not more likely than not as of December 31, 2023 and 2022. The Company intends to maintain the valuation allowances until sufficient positive evidence exists to support the reversal of the valuation allowances. The calculation of the Company’s accruals for tax contingencies involves dealing with uncertainties in the application of complex tax laws. The Company’s estimates for the potential outcome of any uncertain tax issue are based on the detailed facts and circumstances of each issue. Resolution of these uncertainties in a manner inconsistent with the Company’s expectations could have a material impact on its results of operations and financial condition. The Company recognizes liabilities for uncertain tax positions based on a two-step process. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to estimate and measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. It is inherently difficult and subjective to estimate such amounts, as this requires the Company to determine the probability of various possible outcomes. The Company reevaluates these uncertain tax positions on a quarterly basis. This evaluation is based on factors including, but not limited to, changes in facts or circumstances, changes in tax law, effectively settled issues under audit, and new audit activity. Such a change in recognition or measurement would result in the recognition of a tax benefit or an additional charge to tax expense in the period. Interest and penalties related to unrecognized tax benefits are included within income tax (expense) benefit. Basic and Diluted Net Loss per Share Basic and diluted net loss per share is calculated based upon the weighted-average number of shares of common stock outstanding during the period. Shares of common stock that are potentially issuable for little or no cash consideration at issuance, such as the Company’s pre-funded warrants issued in July 2022 and December 2023 are included in the calculation of basic and diluted net loss per share, even if they are antidilutive. During periods of income, participating securities are allocated a proportional share of income determined by dividing total weighted-average participating securities by the sum of the total weighted-average common shares and participating securities (the “two-class method”). Shares of the Company’s common stock warrants participate in any dividends that may be declared by the Company and are therefore considered to be participating securities. Participating securities have the effect of diluting both basic and diluted earnings per share during periods of income. During periods of loss, no loss is allocated to participating securities since they have no contractual obligation to share in the losses of the Company. Diluted loss per share is computed after giving consideration to the dilutive effect of stock options, RSUs, PSUs and common stock warrants, except where such non-participating securities would be anti-dilutive. As the Company incurred net losses for the periods presented, basic net loss per share is the same as diluted net loss per share since the effects of potentially dilutive securities are antidilutive. Comprehensive Loss The Company’s comprehensive loss is comprised of net loss and changes in unrealized gains or losses on marketable securities and foreign currency translation adjustments. Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40)—Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies the accounting for convertible instruments, amends the guidance on derivative scope exceptions for contracts in an entity’s own equity, and modifies the guidance on diluted earnings per share calculations as a result of these changes. The Company early adopted ASU 2020-06 as of January 1, 2023, using a modified retrospective approach and the adoption did not have a material impact on the Company’s consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which is intended to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant expenses. ASU 2023-07 requires disclosures to include significant segment expenses that are regularly provided to the CODM, a description of other segment items by reportable segment, and any additional measures of a segment's profit or loss used by the CODM when deciding how to allocate resources. The ASU also requires all annual disclosures required by Topic 280 to be included in interim periods. The ASU is effective for the Company’s annual periods beginning on January 1, 2024 and interim periods beginning on January 1, 2025. Early adoption is permitted and requires retrospective application to all prior periods presented in the financial statements. The Company is currently evaluating the effect of adopting this new accounting guidance on its financial statement disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires companies to disclose, on an annual basis, specific categories in the effective tax rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. In addition, ASU 2023-09 requires companies to disclose additional information about income taxes paid. The ASU is effective for the Company’s annual periods beginning on January 1, 2025 and will be applied on a prospective basis with the option to apply the standard retrospectively. The Company is currently evaluating the effect of adopting this new accounting guidance on its financial statement disclosures.

Income Taxes - Summary of Loss from Operations Before Taxes on Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Line Items]
Net loss before income tax	$ (138,322)	$ (102,007)	$ (90,269)
United States
Income Tax Disclosure [Line Items]
Net loss before income tax	(138,293)	(101,938)	(91,141)
LITHUANIA
Income Tax Disclosure [Line Items]
Net loss before income tax	(59)	(7)	10
Israel
Income Tax Disclosure [Line Items]
Net loss before income tax	$ 30	$ (62)	$ 862

- Definition

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

+ References

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

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

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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

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

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479557/942-235-S99-1

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-SubTopic 20
-Topic 940
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481913/940-20-25-1

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Consolidated Balance Sheet Components - Schedule of Prepaid and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid research and development	$ 11,579	$ 5,727
Prepaid taxes	614	646
Prepaid other	2,471	1,547
Total prepaid and other current assets	$ 14,664	$ 7,920

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	11. Subsequent Events The Company has evaluated events subsequent to December 31, 2023 and through the financial statement issuance date of March 1, 2024, and concluded that no material events occurred that would require disclosure.

Fair Value Measurements - Schedule of Contractual Maturities of Cash Equivalents and Marketable Securities (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Fair Value Disclosures [Abstract]
Within one year	$ 290,756
After one year through two years	70,546
Total cash equivalents and marketable securities	$ 361,302