0000950170-24-037610 | 10-K | XBRL Viewer

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

9. Commitments and Contingencies

Operating Lease Commitments

In September 2021, the Company entered into a five-year noncancelable facilities lease agreement for approximately 9,600 square feet of office space in Waltham, Massachusetts. The monthly rental payments under the lease, which include base rent charges of $0.4 million per year, are subject to periodic rent increases through September 2026. In addition to base rent, monthly rental payments include the Company’s proportionate share of operating expenses. The lease terms provide for one five-year extension term with base rent calculated on the then-market rate.

In June 2022, the Company entered into a two-year noncancelable agreement for dedicated laboratory and office space in Newton, Massachusetts (the “Newton, MA Lease”). The monthly rental payments under the agreement include base rent charges of $0.7 million per year. The agreement terms provide for a month-to-month extension after completion of the initial two-year term with base rent calculated on the then-market rate with three months’ prior notice.

In September 2022, the Company amended the Newton, MA Lease. Pursuant to the amendment, the Company entered into a separate two-year noncancelable agreement for new dedicated laboratory and office space on the same campus as the Newton, MA Lease. The Company took occupancy of the new dedicated laboratory and office space in December 2022. The monthly rental payments under the amended agreement include base rent charges of $1.3 million per year. The agreement terms provide for a month-to-month extension, after completion of the initial two-year term extending through November 2024, with base rent calculated on the then-market rate with three months’ prior notice.

The components of operating lease expense were as follows (in thousands):


	Year Ended December 31,
	2023		2022
Lease cost:
Operating lease cost	$	1,720	$	754
Variable lease cost		46		31
Total lease cost	$	1,766	$	785

Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows related to operating leases	$	1,731	$	837

Future minimum lease payments under the noncancelable leases as of December 31, 2023 was as follows (in thousands):


Year Ending December 31,	Operating Lease
2024		1,521
2025		430
2026		328
2027		—
Total lease payments		2,279
Present value adjustment		(114	)
Present value of operating lease liability	$	2,165

As of December 31, 2023, the Company’s operating leases were measured using a weighted-average incremental borrowing rate of 6.0% over a weighted-average remaining lease term of 1.8 years.

As of December 31, 2022, the Company’s operating leases were measured using a weighted-average incremental borrowing rate of 6.0% over a weighted-average remaining lease term of 2.6 years.

The total operating liabilities are presented on the Company’s consolidated balance sheet based on maturity dates. $1.4 million is classified under “operating lease liabilities, current” for the portion due within twelve months, and $0.7 million is classified under “operating lease liabilities, non-current”.

License Agreements

The Company has entered into license agreements with Adimab and WuXi Biologics (see Note 7).

Other Agreements

In November 2022, the Company entered into the PHP MSA (see Note 8). Concurrently with the PHP MSA, the Company entered into the PHP Work Order, pursuant to which PHP agreed to advise and counsel the Company regarding clinical development and regulatory matters with respect to its product candidates. The PHP Work Order was effective for six months from November 2022 and terminated in accordance with its terms in May 2023. As compensation for the services and deliverables under the PHP Work Order, the Company paid PHP a cash fee of $0.5 million per month during the term of the PHP Work Order for an Aggregate Fee of $3.0 million.

Clinical and Manufacturing Agreements

In December 2020, the Company entered into a Commercial Manufacturing Services Agreement with WuXi Biologics, which was amended and restated in August 2021 and further amended and restated in September 2023 (as amended and restated, the “Commercial Manufacturing Agreement”). The Commercial Manufacturing Agreement outlines the terms and conditions under which WuXi Biologics manufactures drug substance and drug product for commercial use.

During the year ended December 31, 2023, the Company committed to noncancelable purchase obligations related to commercial drug substance and drug product manufacturing under the Commercial Manufacturing Agreement. As of December 31, 2023, the total remaining contractually binding commercial drug substance and drug product purchase obligations due to WuXi Biologics was $33.9 million, which is expected to be paid in 2024. As of December 31, 2023, $24.1 million related to the contractually binding commercial drug substance and drug product batches was included in accounts payable and accrued expenses, which is expected to be paid in 2024.

During the first quarter of 2024, the Company committed to additional noncancelable purchase obligations of $24.7 million related to the procurement of materials to be used in future drug substance and drug product manufacturing under the Commercial Manufacturing Agreement.

During the first quarter of 2024, the Company committed to additional noncancelable purchase obligations of $50.3 million related to commercial drug substance and drug product manufacturing under the Commercial Manufacturing Agreement.

Unless earlier terminated, the Commercial Manufacturing Agreement remains in effect for an initial period of five years from the date of the last amendment and restatement of the agreement and thereafter automatically renews for further successive periods of five years each. Either party may terminate the agreement upon the breach or default by the other party, other than a non-payment breach, that is not timely cured after notice thereof. Both parties are also entitled to terminate the Commercial Manufacturing Agreement if the other party becomes insolvent or is the subject of a petition in bankruptcy or of any other related proceeding or event. Either party may terminate either the Commercial Manufacturing Agreement in its entirety, or an individual order, (i) to the extent the other party suffers a force majeure event that is continuing for a predefined period of time and (ii) if the other party fails to make a payment when due under the arrangement and such non-payment is not timely cured after notice thereof. Until regulatory approval and future economic benefit is probable, the Company will continue to expense costs related to batches manufactured under the Commercial Manufacturing Agreement.

Other Contracts

The Company enters into agreements with third parties in the ordinary course of business for various products and services, including those related to research, preclinical and clinical operations, manufacturing and support, supply chain, and distribution. These contracts do not contain any material minimum purchase commitments. Certain of these agreements provide for termination rights subject to the payment of termination fees and/or wind-down costs. Under such agreements, the Company is contractually obligated to make certain payments to vendors upon early termination, primarily to reimburse them for their unrecoverable outlays incurred prior to cancellation as well as any amounts owed by the Company prior to early termination. The actual amounts the Company could pay in the future to the vendors under such agreements may differ from the purchase order amounts due to cancellation provisions. The termination fees were not probable of payment as of December 31, 2023 and 2022.

Legal Proceedings

From time to time, the Company may become involved in legal proceedings or other litigation relating to claims arising in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. Significant judgment is required to determine both probability and estimated exposure amount. Legal fees and other costs associated with such proceedings are expensed as incurred.

On January 31, 2023, a securities class action lawsuit captioned Brill v. Invivyd, Inc., et. al., Case No. 1:23-CV-10254-LTS, was filed against the Company and certain of its former officers in the U.S. District Court for the District of Massachusetts. The complaint alleges violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder on the basis of purportedly materially false and misleading statements and omissions concerning ADG20’s effectiveness against the Omicron variant of COVID-19. The complaint seeks, among other things, unspecified damages, attorneys’ fees, expert fees, and other costs. The court appointed lead plaintiffs for the action on June 28, 2023. On August 23, 2023, the lead plaintiffs filed an amended complaint that makes allegations similar to those in the original complaint and asserts the same claims against the same defendants as the original complaint. On October 19, 2023, the parties filed a joint stipulation to advise the court that the lead plaintiffs intended to seek leave to file a second amended complaint, and on November 22, 2023, the lead plaintiffs filed a second amended complaint that makes allegations similar to those in the prior complaints and asserts the same claims against the same defendants as the prior complaints. On January 12, 2024, the defendants filed a motion to dismiss the second

amended complaint in its entirety. The lead plaintiffs filed an opposition to the motion to dismiss on February 26, 2024, and the defendants filed a reply in further support of their motion to dismiss on March 27, 2024.

The Company believes that is has strong defenses, and it intends to vigorously defend against this action. The lawsuit is in early stages, and, at this time, no assessment can be made as to the likely outcome or whether the outcome will be material to the Company.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to its vendors, lessors, CROs, contract development and manufacturing organizations (“CDMOs”), business partners and other parties with respect to certain matters, including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and its executive officers that require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or executive officers. The maximum potential amount of future payments that the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims.

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Schedule of Weighted Average Fair Values and Valuation Assumptions

The following table presents, on a weighted-average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted:


	2023			2022
Expected term (in years)		5.9			6.0
Expected volatility		66.1	%		71.8	%
Risk-free interest rate		3.8	%		2.7	%
Expected dividend yield		—	%		—	%

Summary of Stock Option Activity

The following table summarizes the Company’s stock option activity since December 31, 2022:


	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
						(in years)		(in thousands)
Outstanding at December 31, 2022		23,239,391		$	7.01		7.9	$	1,594
Granted		9,862,389		$	2.36
Exercised		(1,224,330	)	$	0.78
Forfeited		(8,811,936	)	$	7.72
Outstanding at December 31, 2023		23,065,514		$	5.08		8.7	$	24,745
Vested and expected to vest at December 31, 2023		23,065,514		$	5.08		8.7	$	24,745
Options exercisable at December 31, 2023		7,371,263		$	7.30		8.0	$	5,195

Schedule of Unvested Common Stock Options

A summary of the Company’s unvested common stock from option early exercises that is subject to repurchase by the Company is as follows:


	Number of Shares
Unvested restricted stock at December 31, 2022		360,333
Issued		—
Vested		(75,166	)
Repurchased		(285,167	)
Unvested restricted stock at December 31, 2023		—

Summary of Share Based Compensation Expense Recognized

The Company recorded stock-based compensation expense in the following expense categories of its consolidated statements of operations and comprehensive loss (in thousands):


	2023		2022
Research and development	$	6,240	$	12,800
Selling, general and administrative		12,445		8,848
	$	18,685	$	21,648

PHP Warrants [Member]

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Schedule of Weighted Average Fair Values and Valuation Assumptions

Assumptions used to determine the fair value of PHP Warrant using the simulation model based on Geometric Brownian Motion in a risk-neutral framework are as follows:


	Year Ended December 31,
	2022
Weighted-average grant date fair value per warrant	$	2.55
Expected term (in years)		10.0
Expected volatility		70.0	%
Risk-free interest rate		3.8	%
Expected dividend yield		—	%
Common shares outstanding		108,982,401

- 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

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+ Details

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 200,641	$ 92,076
Marketable securities	0	279,915
Prepaid expenses and other current assets	24,240	4,926
Total current assets	224,881	376,917
Property and equipment, net	1,896	2,282
Operating lease right-of-use asset	2,229	3,777
Other non-current assets	175	191
Total assets	229,181	383,167
Current liabilities:
Accounts payable	7,953	1,517
Accrued expenses	40,860	21,911
Operating lease liabilities, current	1,443	1,559
Other current liability	35	44
Total current liability	50,291	25,031
Operating lease liabilities, non-current	722	2,165
Other non-current liability	700	0
Early-exercise liability	0	1
Total liabilities	51,713	27,197
Commitments and contingencies (Note 9)
Stockholders' equity (deficit):
Preferred stock (undesignated), $0.0001 par value; 10,000,000 shares authorized and no shares issued and outstanding at December 31, 2023 and December 31, 2022	0	0
Common stock, $0.0001 par value; 1,000,000,000 shares authorized, 110,160,684 shares issued and outstanding at December 31, 2023; 109,044,046 shares issued and outstanding at December 31, 2022	11	11
Additional paid-in capital	909,539	889,657
Accumulated other comprehensive loss	(13)	(272)
Accumulated deficit	(732,069)	(533,426)
Total stockholders' equity	177,468	355,970
Total liabilities, preferred stock and stockholders' equity	$ 229,181	$ 383,167

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDER'S DEFICIT - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock, Common [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2021	$ 558,019	$ 11		$ 850,125	$ (8)	$ (292,109)
Balances, shares at Dec. 31, 2021		110,782,909
Treasury stock at Dec. 31, 2021			$ 0
Treasury Stock, Common, Shares at Dec. 31, 2021			468,751
Issuance of warrants for common stock	17,373			17,373
Exercise of stock options	241			241
Exercise of stock options, shares		298,353
Retirement of treasury shares, shares			(2,619,488)
Vesting of restricted common stock from early-exercised options	1			1
Repurchase of unvested restricted common stock (in shares)		(2,150,737)	2,150,737
Stock-based compensation expense	21,648			21,648
Issuance of common stock under the employee stock purchase plan	269			269
Issuance of common stock under the employee stock purchase plan, shares		113,521
Unrealized gain (loss) on available-for-sale securities, net of tax	(264)				(264)
Net Income (Loss)	(241,317)					(241,317)
Balance at Dec. 31, 2022	355,970	$ 11		889,657	(272)	(533,426)
Balance, shares at Dec. 31, 2022		109,044,046
Treasury stock at Dec. 31, 2022			$ 0
Treasury Stock, Common, Shares at Dec. 31, 2022			0
Exercise of stock options	955			955
Exercise of stock options, shares		1,224,330
Retirement of treasury shares, shares			(285,167)
Vesting of restricted common stock from early-exercised options	2			2
Repurchase of unvested restricted common stock (in shares)		(285,167)	285,167
Stock-based compensation expense	18,685			18,685
Issuance of common stock under the employee stock purchase plan	240			240
Issuance of common stock under the employee stock purchase plan, shares		177,475
Unrealized gain (loss) on available-for-sale securities, net of tax	259				259
Net Income (Loss)	(198,643)					(198,643)
Balance at Dec. 31, 2023	$ 177,468	$ 11		$ 909,539	$ (13)	$ (732,069)
Balance, shares at Dec. 31, 2023		110,160,684
Treasury stock at Dec. 31, 2023			$ 0
Treasury Stock, Common, Shares at Dec. 31, 2023			0

Commitments and Contingencies - Schedule of Future Minimum Payments Under Non-cancellable Purchase Obligations (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2024	$ 1,521
2025	430
2026	328
2027	0
Total lease payments	2,279
Present value adjustment	(114)
Present value of operating lease liability	$ 2,165

Common Stock

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Common Stock

10. Common Stock

Shares Reserved for Future Issuance

As of December 31, 2023 the Company had reserved 43,048,016 shares of common stock for the exercise of outstanding stock options and the issuance of awards available for grant under the Company’s 2020 Equity Incentive Plan, 2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan (see Note 11).

Shelf Registration Statement

In September 2022, the Company filed a shelf registration statement on Form S-3 with the SEC (File No. 333-267643) and accompanying base prospectus, which was declared effective by the SEC on October 5, 2022, for the offer and sale of up to $400 million of the Company’s securities. As of December 31, 2023, $325 million of the Company's securities remained available for offer and sale under this shelf registration statement.

ATM Facility

In December 2023, the Company entered into a Controlled Equity OfferingSM Sales Agreement (the “Sales Agreement”) with Cantor Fitzgerald & Co., as sales agent (“Cantor”), pursuant to which the Company may, at its option, offer and sell shares of its common stock, with a sales value of up to $75.0 million, from time to time, through Cantor, acting as sales agent, in transactions deemed to be “at the market offerings”, as defined in Rule 415 under the Securities Act. Cantor is entitled to a commission of 3% of the gross proceeds from any sales of such shares. The Company did not sell any shares of its common stock through the year ended December 31, 2023. As of December 31, 2023, $75.0 million remained available for sale under the Sales Agreement.

In February 2024, the Company sold 9,000,000 shares of its common stock under the Sales Agreement at an average price of $4.50 per share for $39.3 million in net proceeds.

Treasury Stock

In February and June 2022, the Company repurchased 1,158,089 and 992,648 shares of unvested restricted common stock, respectively, at the original purchase price upon a termination of service during the vesting period. The shares of common stock repurchased were recorded as treasury stock in the accompanying consolidated balance sheets and consolidated statements of stockholders’ equity (deficit) as such shares were not retired. The fair value of the repurchased common stock was insignificant.

In March and September 2022, the Company retired an aggregate of 1,626,840 and 992,648 shares of common stock, respectively, held in treasury. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company’s common stock.

In March 2023, the Company repurchased, and subsequently retired, 206,802 shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The fair value of the repurchased common stock was insignificant. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company’s common stock.

In May 2023, the Company repurchased 46,600 shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The shares of common stock repurchased were recorded as treasury stock. The fair value of the repurchased common stock was insignificant. In June 2023, the Company retired the 46,600 shares of treasury stock. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company’s common stock.

In October 2023, the Company repurchased 31,765 shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The shares of common stock repurchased were recorded as treasury stock. The fair value of the repurchased common stock was insignificant. In December 2023, the Company retired the 31,765 shares of treasury stock. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company’s common stock.

- Definition

The entire disclosure for equity.

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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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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

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Quarterly Fee	$ 1,300
Research and Development Expense [Member]
Related Party Transaction [Line Items]
Quarterly Fee	5,200	$ 5,200
Adimab Assignment Agreement [Member] \| In Process Research And Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	3,600	0
Adimab Assignment Agreement [Member] \| Research and Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	0	600
Adimab Collaboration Agreement [Member] \| In Process Research And Development Expense [Member]
Related Party Transaction [Line Items]
Option Exercise Fee	1,000	1,000
Drug delivery fees	200	400
Optimization completion fee payable to related party	200
Adimab Collaboration Agreement [Member] \| Research and Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	500	1,700
Quarterly Fee	5,200	5,200
Adimab Platform Transfer Agreement [Member] \| In Process Research And Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party		3,000
Adimab [Member]
Related Party Transaction [Line Items]
Due To Related Parties	700	300
Due from Related Party	0	0
Adimab [Member] \| Research and Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	100
Mithril Group [Member]
Related Party Transaction [Line Items]
Due from Related Party	0
Mithril Group [Member] \| Research and Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party		1,400
PHP Member
Related Party Transaction [Line Items]
Due To Related Parties	0	800
Due from Related Party	0	0
PHP Member \| Warrant [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	0	17,400
PHP Member \| Research and Development Expense [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transaction With Related Party	$ 2,200	$ 800

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

Common Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended				12 Months Ended
	May 31, 2023	Jun. 30, 2022	Feb. 28, 2022	Feb. 29, 2024	Oct. 31, 2023	Mar. 31, 2023	Sep. 30, 2022	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2023	Mar. 31, 2022
Convertible preferred stock shares reserved for future issuance								43,048,016
Security for sale offering							$ 400,000
Common stock, shares issued								110,160,684	109,044,046
Common stock, par value								$ 0.0001	$ 0.0001
Proceeds from Issuance of Common Stock								$ 240	$ 269
Shelf Registration Statement [Member]
Debt securities, available-for-sale								325,000
ATM Facility [Member]
Security for sale offering								$ 75,000
Commission On Sales								3.00%
Treasury Stock, Common [Member]
Common stock, shares issued								31,765		46,600	1,626,840
Common stock shares held							992,648
Common shares repurchased	46,600	992,648	1,158,089		31,765	206,802
Sales Agreement [Member]
Security for sale offering								$ 75,000
Sales Agreement [Member] \| Subsequent Event [Member]
Common stock, par value				$ 4.5
Proceeds from Issuance of Common Stock				$ 39,300
Issuance of common stock, shares				9,000,000

Stock-Based Compensation - Schedule of Unvested Common Stock From Option Early Exercises (Details)	12 Months Ended
	Dec. 31, 2023 shares
Share-Based Payment Arrangement [Abstract]
Unvested restricted stock at December 31, 2022	360,333
Issued	0
Vested	(75,166)
Repurchased	(285,167)
Unvested restricted stock at December 31, 2023	0

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Percentage of income tax examination likelihood upon ultimate settlement	50.00%
Unrecognized tax benefits accrued for interest and penalties	$ 0	$ 0
Impairment loss	0	0
Annual gross revenue	1,235,000
Realized gains or losses on marketable securities recognized	0	0
Operating lease right-of-use asset	2,229	3,777
Operating lease liabilities, current	1,443	1,559
Convertible Debt	1,000,000
Other non-current liability	700	0
Operating lease liabilities, non-current	$ 722	$ 2,165

Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2023

Marketable Securities [Abstract]

Summary of Marketable Securities

The following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of December 31, 2022 (in thousands):


December 31, 2022	Amortized Cost		Unrealized Gains		Unrealized Losses			Credit Losses		Fair Value
U.S. Treasury securities	$	107,973	$	13	$	(115	)	$	—	$	107,871
Federal agency securities		172,214		39		(209	)		—		172,044
Total financial assets	$	280,187	$	52	$	(324	)	$	—	$	279,915

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid external research, development and manufacturing costs	$ 19,962	$ 843
Prepaid Insurance	1,770	2,392
Prepaid compensation and other	1,575	1,314
Interest receivable	933	377
Prepaid expenses and other current assets	$ 24,240	$ 4,926

Related Party Transactions

12 Months Ended

Dec. 31, 2023

Related Party Transactions

15. Related Party Transactions

As of December 31, 2023 and December 31, 2022, an aggregate of $0.7 million and $0.3 million, respectively, was due to Adimab under the Adimab Assignment Agreement, the Adimab Collaboration Agreement, the Adimab Platform Transfer Agreement and the Adimab DNA Sequencing Services Agreement (as defined below) by the Company. As of December 31, 2023 and 2022, no amounts were due to the Company from Adimab under the Adimab Assignment Agreement, the Adimab Collaboration Agreement, the Adimab Platform Transfer Agreement or the Adimab DNA Sequencing Services Agreement.

Adimab Assignment Agreement

Under the Adimab Assignment Agreement, Adimab, a principal stockholder of the Company, is entitled to receive milestone and royalty payments upon specified conditions, and receives payments from the Company for providing ongoing services under the agreement (see Note 7).

During the year ended December 31, 2023, the Company recognized $3.6 million as IPR&D expense with respect to milestones payable under the Adimab Assignment Agreement. During the year ended December 31, 2022, the Company did not recognize any IPR&D expense with respect to milestones payable under the Adimab Assignment Agreement.

During the year ended December 31, 2023, the Company did not recognize any research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab Assignment Agreement. During the year ended December 31, 2022, the Company recognized $0.6 million of research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab Assignment Agreement.

Adimab Collaboration Agreement

Under the Adimab Collaboration Agreement, the Company is obligated to pay Adimab for certain fees, milestones and royalty payments (see Note 7).

During both the years ended December 31, 2023 and 2022, the Company recognized $5.2 million of research and development expense related to the quarterly fee under the Adimab Collaboration Agreement.

During the years ended December 31, 2023 and 2022, the Company recognized $0.5 million and $1.7 million, respectively, of research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab Collaboration Agreement.

During both the years ended December 31, 2023 and 2022, the Company recognized $1.0 million of IPR&D expense related to an option exercise fee under the Adimab Collaboration Agreement.

During the years ended December 31, 2023 and 2022, the Company recognized $0.2 million and $0.4 million, respectively, of IPR&D expense related to drug delivery fees under the Adimab Collaboration Agreement.

During the year ended December 31, 2023, the Company recognized $0.2 million of IPR&D expense related to an optimization completion fee under the Adimab Collaboration Agreement. During the year ended December 31, 2022, the Company did not recognize any IPR&D expense related to an optimization completion fee under the Adimab Collaboration Agreement.

Adimab Platform Transfer Agreement

Under the Adimab Platform Transfer Agreement, the Company is obligated to pay Adimab for certain fees, milestones and royalty payments (see Note 7).

During the year ended December 31, 2023, the Company recognized a portion of the first annual fee as research and development expense under the Adimab Platform Transfer Agreement.

During the year ended December 31, 2022, the Company recognized $3.0 million of IPR&D expense in connection with the upfront consideration payable for the rights assigned under the Adimab Platform Transfer Agreement.

Adimab DNA Sequencing Services Agreement

In May 2023, as amended in January 2024, the Company entered into a Services Agreement with Adimab for Adimab to perform DNA sequencing on yeast samples provided by the Company, and the delivery of the resulting data and information to the Company (the “Adimab DNA Sequencing Services Agreement”). In exchange for the services performed, the Company will pay Adimab a fee for each yeast-derived DNA template sample present in the well within the sequencer plate.

During the year ended December 31, 2023, the Company recognized less than $0.1 million of research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab DNA Sequencing Services Agreement.

Mithril Group

In March 2022, a group of stockholders, including, among others, Adimab; Mithril II LP; M28 Capital Management LP; Polaris Venture Partners V, L.P.; and Population Health Equity Partners III, L.P., which are collectively referred to as the Mithril Group, submitted a notice of intent to nominate three directors to the Company’s board of directors at the 2022 annual meeting of stockholders. In April 2022, the Mithril Group filed definitive proxy materials with the SEC seeking election of three directors to the Company’s board of directors and adoption of a non-binding resolution for director declassification.

Subsequently, during the year ended December 31, 2022, Mithril II LP requested that the Company reimburse it for costs associated with legal expenses, corporate governance matters and stockholder proposals incurred as a result of the aforementioned matters in connection with the Company’s 2022 annual meeting of stockholders. The Company made such reimbursement payment to Mithril II LP in the amount of $1.4 million, which the Company recognized as a selling, general and administrative expense.

During the year ended December 31, 2023, the Company did not recognize any expense related to the Mithril Group. As of December 31, 2023, no amounts were due to any member of the Mithril Group by the Company, and no amounts were due from any member of the Mithril Group to the Company.

Population Health Partners, L.P.

Under the PHP MSA and PHP Work Order, the Company was obligated to pay cash compensation for services and deliverables (see Note 8). Clive Meanwell, M.D. and Tamsin Berry, members of the Company’s board of directors, are Managing Partner and Limited Partner of PHP, respectively.

During the years ended December 31, 2023 and 2022, the Company recognized $2.2 million and $0.8 million, respectively, of research and development expense related to services performed by PHP in connection with the PHP Work Order, which terminated in accordance with its terms in May 2023.

During the year ended December 31, 2023, the Company did not recognize any warrant expense. During the year ended December 31, 2022, the Company recognized $17.4 million of warrant expense related to warrants issued to PHP in connection with the PHP Warrant.

As of December 31, 2023, no amounts were due to PHP by the Company, and no amounts were due from PHP to the Company. As of December 31, 2022, $0.8 million was due to PHP by the Company, and no amounts were due from PHP to the Company.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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+ Details

Nature of the Business and Basis of Presentation

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of the Business and Basis of Presentation

1. Nature of the Business and Basis of Presentation

Invivyd, Inc. is a commercial-stage company on a mission to rapidly and perpetually deliver antibody-based therapies that protect vulnerable people from the devastating consequences of circulating viral threats, beginning with SARS-CoV-2. The Company’s proprietary INVYMAB™ platform approach combines state-of-the-art viral surveillance and predictive modeling with advanced antibody engineering. INVYMAB is designed to facilitate the rapid, serial generation of new monoclonal antibodies (“mAbs”) to keep pace with evolving viral threats.

On March 22, 2024, the Company received emergency use authorization (“EUA”) from the U.S. Food and Drug Administration (“FDA”) for PEMGARDA™ (pemivibart) injection, for intravenous use, a half-life extended investigational mAb, for the pre-exposure prophylaxis (prevention) of COVID-19 in adults and adolescents (12 years of age and older weighing at least 40 kg) who have moderate-to-severe immune compromise due to certain medical conditions or receipt of certain immunosuppressive medications or treatments and are unlikely to mount an adequate immune response to COVID-19 vaccination. Recipients should not be currently infected with or have had a known recent exposure to an individual infected with SARS-CoV-2.

PEMGARDA is the Company’s first mAb in a planned series of innovative mAb candidates designed to keep pace with SARS-CoV-2 viral evolution. As the SARS-CoV-2 virus evolves over time, the Company anticipates leveraging its INVYMAB platform approach to periodically introduce new or engineered mAb candidates, an approach that would be analogous to the periodic updates made to influenza and COVID-19 vaccines. In January 2024, the Company nominated VYD2311, a mAb optimized for neutralization potency against recent SARS-CoV-2 lineages such as BA.2.86 and JN.1, as a drug candidate, and the Company expects it will be the next pipeline program to advance into clinical development. In addition to developing candidates for COVID-19, the Company expects to apply its INVYMAB platform approach to produce lead molecules for other viral diseases, such as influenza.

The Company was incorporated in the State of Delaware in June 2020. The Company operates as a hybrid company with employees working at its corporate headquarters in Waltham, Massachusetts and remotely. In June 2022, and subsequently amended in September 2022, the Company entered into a lease for dedicated laboratory and office space in Newton, Massachusetts for research and development purposes. In 2022, the Company expanded its research team in order to enable internal discovery and development of its mAb candidates, while continuing to leverage the Company’s existing partnership with Adimab, LLC (“Adimab”). The Company is focused on antibody discovery and use of Adimab’s platform technology while building its own internal capabilities. In addition, the Company performs research and development activities internally and engages third parties, including Adimab, to perform ongoing research and development and other services on its behalf.

The Company is subject to a number of risks and uncertainties common to companies in the biopharmaceutical industry, including, but not limited to, completing clinical trials, the ability to raise additional capital to fund operations, obtaining regulatory authorization or approval for product candidates, market acceptance of products, competition from other products, protection of proprietary intellectual property, compliance with government regulations, dependence on key personnel, the ability to attract and retain qualified employees, and reliance on third-party organizations for the discovery, manufacturing, clinical and commercial success of its product candidates.

Through December 31, 2023, the Company has not generated any revenue. To date, the Company has received regulatory authorization for only one product candidate, PEMGARDA, which has not been approved, but has been authorized for emergency use by the FDA under an EUA, for pre-exposure prophylaxis of COVID-19 in certain adults and adolescent individuals (12 years of age and older weighing at least 40 kg). All of its other product candidates, other than adintrevimab, are currently in preclinical development. The Company’s additional product candidates require significant additional research and development efforts, including extensive clinical testing, and regulatory authorization or approval prior to potential commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and compliance-reporting capabilities. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will generate substantial revenue from product sales to be able to fund its operating expenses and capital requirements.

Substantial Doubt about Ability to Continue as a Going Concern

The accompanying consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets, and the satisfaction of liabilities and commitments in the ordinary course of business. The Company has primarily funded its operations with proceeds from sales of convertible preferred stock and proceeds from the Company’s initial public offering (“IPO”). The Company has incurred losses and negative cash flows from operations since its inception,

including a net loss of $198.6 million for the year ended December 31, 2023. As of December 31, 2023, the Company had an accumulated deficit of $732.1 million. The Company may continue to generate operating losses for the foreseeable future.

In February 2024, the Company sold 9,000,000 shares of its common stock under the Sales Agreement (defined below) at an average price of $4.50 per share for $39.3 million in net proceeds.

Based on current operating plans and excluding any contribution from revenues or external financing, the Company believes that its existing cash and cash equivalents will be sufficient to fund its operating expenses and capital expenditure requirements into the fourth quarter of 2024. As such, excluding any contribution from revenues or external financing, the Company will not have sufficient cash and cash equivalents to fund its operating expenses and capital requirements beyond one year from the issuance of these consolidated financial statements, and therefore, the Company has concluded that there is substantial doubt about its ability to continue as a going concern.

The Company will require additional funding through a combination of contribution from revenues, equity offerings, government or private-party grants, debt financings or other capital sources, such as collaborations with other companies, strategic alliances or licensing arrangements to finance its future operations. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or rights of the Company’s stockholders.

If the Company is unable to obtain sufficient capital, the Company will be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all.

Basis of Presentation

The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

The accompanying consolidated financial statements include the accounts of Invivyd, Inc. and its wholly owned subsidiaries, Invivyd Security Corporation, Invivyd Switzerland GmbH, and Invivyd Netherlands B.V. All intercompany accounts and transactions have been eliminated in consolidation. The Company views its operations and manages its business in one operating segment, which is the business of discovering, developing and commercializing differentiated products for the prevention and treatment of infectious diseases.

Marketable Securities - Summary of Marketable Securities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 280,187
Unrealized Gains	52
Unrealized Loses	(324)
Fair Value	279,915
US Treasury Securities [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	107,973
Unrealized Gains	13
Unrealized Loses	(115)
Fair Value	107,871
Agency Securities [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	172,214
Unrealized Gains	39
Unrealized Loses	(209)
Fair Value	$ 172,044

Stock-Based Compensation - Summary of Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Number of Shares Beginning Balance	23,239,391
Granted	9,862,389
Exercised	(1,224,330)
Forfeited	(8,811,936)
Number of Shares Ending Balance	23,065,514	23,239,391
Vested and expected to vest	23,065,514
Options exercisable	7,371,263
Beginning Balance	$ 7.01
Granted	2.36
Exercised	0.78
Forfeited	7.72
Ending Balance	5.08	$ 7.01
Vested and expected to vest	5.08
Options exercisable	$ 7.3
Weighted Average Remaining Contractual Term	8 years 8 months 12 days	7 years 10 months 24 days
Weighted Average Remaining Contractual Term, Vested and Expected to vest	8 years 8 months 12 days
Weighted Average Remaining Contractual Term, Exercisable	8 years
Aggregate Intrinsic Value, Outstanding	$ 1,594
Aggregate Intrinsic Value, Outstanding	24,745	$ 1,594
Aggregate Intrinsic Value, Vested and Expected to vest	24,745
Aggregate Intrinsic Value, Exercisable	$ 5,195

Population Health Partners (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
PHP [Member]
Other Commitments [Line Items]
Cash fee payment per month	$ 0.5
Aggregate fee	3.0
Recognized research and development	$ 2.2	$ 0.8
Exercise price	$ 3.48
PHP Warrant [Member]
Other Commitments [Line Items]
Exercisable common stock	6,824,712
PHP Warrant [Member] \| November 15, 2029 [Member]
Other Commitments [Line Items]
Common stock, conversion basis	1,795,977 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization equals or exceeds $1,137,776,266 by November 15, 2029; and
PHP Warrant [Member] \| November 15, 2028 [Member]
Other Commitments [Line Items]
Common stock, conversion basis	3,591,954 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization (as defined below) equals or exceeds $758,517,511 by November 15, 2028;
PHP Warrant [Member] \| November 15, 2030 [Member]
Other Commitments [Line Items]
Common stock, conversion basis	1,436,781 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization equals or exceeds $1,517,035,022 by November 15, 2030.

Stock-Based Compensation - Schedule of Weighted Average Fair Values and Valuation Assumptions (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock	$ 1.46	$ 2.79
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 10 months 24 days	6 years
Expected volatility	66.10%	71.80%
Risk-free interest rate	3.80%	2.70%
Expected dividend yield	0.00%	0.00%

- Definition

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

+ References

+ Details

Net Loss per Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Net Loss per Share

14. Net Loss per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts):


	2023			2022
Numerator:
Net loss attributable to common stockholders	$	(198,643	)	$	(241,317	)
Denominator:
Weighted-average common shares outstanding, basic and diluted		109,526,053			108,268,289
Net loss per share attributable to common stockholders, basic and diluted	$	(1.81	)	$	(2.23	)

Shares of unvested restricted common stock are not considered outstanding for accounting purposes until vested and were excluded from the calculations of basic net loss per share attributable to common stockholders for all periods presented.

The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated, because including them would have had an anti-dilutive effect:


	2023		2022
Stock options to purchase common stock		23,065,514		23,239,391
Unvested restricted common stock		—		360,333
Warrants to purchase common stock		6,824,712		6,824,712
		29,890,226		30,424,436

Net Loss per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	29,890,226	30,424,436
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	6,824,712	6,824,712
Employee Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	23,065,514	23,239,391
Unvested Restricted Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	360,333

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

Cash flows from operating activities:

Net loss

$ (198,643)

$ (241,317)

Adjustments to reconcile net loss to net cash used in operating activities:

Stock-based compensation expense

18,685

21,648

Warrant expense

^[1]

17,373

Net amortization of premiums and accretion of discounts on marketable securities

(1,122)

(2,023)

Amortization of operating lease right-of-use assets

1,548

421

Depreciation Expense

480

Changes in operating assets and liabilities:

Prepaid expenses and other current assets

(18,892)

20,367

Other non-current assets

3,106

Accounts payable

6,471

(4,300)

Accrued expenses

19,162

(34,867)

Operating lease liabilities

(1,559)

(475)

Other current liabilities

(10)

Other non-current liabilities

700

(5)

Net cash used in operating activities

(173,164)

(219,987)

Cash flows from investing activities:

Purchases of marketable securities

(91,202)

(297,962)

Maturities of marketable securities

372,501

69,000

Purchases of property and equipment

(615)

(1,705)

Net cash provided by (used in) investing activities

280,684

(230,667)

Cash flows from financing activities:

Proceeds from exercises of stock options

955

241

Proceeds from issuance of common stock under the employee stock purchase plan

240

269

Payments for offering costs

(149)

Payments for repurchases of unvested restricted common stock

(1)

(4)

Net cash provided by financing activities

1,045

506

Net increase (decrease) in cash and cash equivalents

108,565

(450,148)

Cash and cash equivalents at beginning of period

92,076

542,224

Cash and cash equivalents at end of period

200,641

92,076

Supplemental disclosure of cash flow information:

Operating lease right-of-use asset recognized upon adoption of ASC 842

1,728

Operating lease right-of-use asset recognized under ASC 842

2,470

Supplemental disclosure of non-cash investing activities:

Purchases of property and equipment in accounts payable and accrued expenses

535

Deferred offering costs in accrued expenses

$ 273

$ 0

[1]	Includes related-party amounts of $0 and $17,373 for the years ended December 31, 2023 and 2022, respectively (see Note 15).

License and Collaboration Agreements - Additional Information (Details) - USD ($) $ in Millions		1 Months Ended				3 Months Ended	12 Months Ended
	Sep. 30, 2022	Jan. 31, 2024	Mar. 31, 2023	Aug. 31, 2021	Jul. 31, 2020	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Acquired IPR&D expense	$ 3.0
Accrued upfront fee									$ 0.2
Quarterly fee							$ 1.3
Delivery fee							0.2
Completion fee							0.2
Exercise fee							$ 1.0
Royalty based on net sales of licensed products, percentage							1.00%
Royalty expense							$ 0.0
Research and Development [Member]
Defined Benefit Plan Disclosure [Line Items]
Quarterly fee							5.2	$ 5.2
Research Development and Regulatory Milestone [Member]
Defined Benefit Plan Disclosure [Line Items]
Potential milestone payment							18.0
Subsequent Event [Member]
Defined Benefit Plan Disclosure [Line Items]
Quarterly fee		$ 0.6
Adimab Assignment Agreement [Member]
Defined Benefit Plan Disclosure [Line Items]
Milestone payment							11.1
Adimab Assignment Agreement [Member] \| Research and Development [Member]
Defined Benefit Plan Disclosure [Line Items]
Recognized expense							0.0	0.6
Adimab Assignment Agreement [Member] \| Acquired In-Process Research and Development Expense [Member]
Defined Benefit Plan Disclosure [Line Items]
Milestone payment			$ 0.4			$ 3.2	$ 3.6
Adimab Assignment Agreement [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Potential milestone payment					$ 24.6
Royalty percentage of sublicense consideration							55.00%
Adimab Assignment Agreement [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Royalty percentage of sublicense consideration							45.00%
Adimab Assignment Agreement [Member] \| First Product [Member]
Defined Benefit Plan Disclosure [Line Items]
Potential milestone payment					16.5
Adimab Assignment Agreement [Member] \| Second Product [Member]
Defined Benefit Plan Disclosure [Line Items]
Potential milestone payment					$ 8.1
TSRI [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount paid as pre-paid funding for research plan				$ 1.5
Research and development expenses							$ 0.0	1.7
Adimab Collaboration Agreement [Member]
Defined Benefit Plan Disclosure [Line Items]
Expenses							0.5	1.7
Adimab Collaboration Agreement [Member] \| Research and Development [Member]
Defined Benefit Plan Disclosure [Line Items]
Quarterly fee							5.2	5.2
Adimab Collaboration Agreement [Member] \| Acquired In-Process Research and Development Expense [Member]
Defined Benefit Plan Disclosure [Line Items]
Delivery fee							0.2	0.4
Completion fee							0.2
Exercise fee							1.0	1.0
Adimab Platform Transfer Agreement [Member] \| Research Development and Regulatory Milestone [Member]
Defined Benefit Plan Disclosure [Line Items]
Potential milestone payment							9.5
Wu Xi Cell Line License Agreement [Member]
Defined Benefit Plan Disclosure [Line Items]
Acquired IPR&D expense							$ 0.0	$ 0.0

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 0	$ 0
Valuation allowance	69,100	68,300
Unrecognized tax benefits accrued for interest and penalties	0	0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 318,600	$ 263,700
Percentage deduction of annual taxable income.	80.00%
Domestic Tax Authority \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 19,300
Tax credit carryforward expiration term	2041
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 153,800
State and Local Jurisdiction \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 6,400
Tax credit carryforward expiration term	2036
Indefinite Period \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 9,600
Tax Year2040 \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 144,200
Operating loss carryforwards expiration	2032

Stock-Based Compensation - Summary of Share Based Compensation Expense Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	$ 18,685	$ 21,648
Research and Development [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	6,240	12,800
Selling, General and Administrative [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock based compensation expense	$ 12,445	$ 8,848

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Use of Estimates

The preparation of the Company’s 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, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, research and development expenses and related prepaid or accrued costs and stock-based compensation expense. The Company bases its estimates on historical experience, known trends and other market-specific or relevant factors it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results may differ materially from those estimates or assumptions.

The Company is monitoring the potential impact of the COVID-19 pandemic on its business and consolidated financial statements. The Company is not aware of any specific event or circumstance that would require any update to its estimates or judgments reflected in these consolidated financial statements or a revision of the carrying value of its assets or liabilities as of the issuance date of these consolidated financial statements. These estimates may change as new events occur and additional information is obtained.

Concentrations of Credit Risk, Significant Suppliers and License Rights

Financial instruments that potentially expose the Company to concentrations of credit risk consist of cash, cash equivalents and marketable securities. As of December 31, 2023, the Company invested its excess cash in money market funds that are subject to minimal credit and market risks. The Company maintains its existing cash and cash equivalents at three accredited financial institutions that it believes are creditworthy. From time to time, these deposits may exceed federally insured limits. The Company has not experienced any losses historically in these accounts. Accordingly, the Company does not believe it is exposed to unusual credit risk related to its existing cash and cash equivalents beyond the normal credit risk associated with commercial banking relationships.

The Company is dependent on third-party organizations to manufacture and process its product candidates for its development programs. In particular, the Company relies on a single third-party contract manufacturer to produce and process its product candidates and to manufacture supply of its product candidates for preclinical and clinical activities. The Company also currently relies on this same third-party contract manufacturer for any anticipated requirements of commercial supply, including both drug substance and drug product (see Note 9). The Company expects to continue to be dependent on a small number of manufacturers to supply it with its requirements for all products. The Company’s research and development programs, including any associated commercialization efforts, could be adversely affected by a significant interruption in the supply of the necessary materials.

The Company is dependent on a limited number of third parties that provide license rights used by the Company in the development and potential commercialization of its product candidates and programs. Through December 31, 2023, the Company’s research and development programs primarily relate to rights conveyed by Adimab (see Note 7). The Company could experience delays in the development and commercialization of its product candidates and programs if the Adimab agreements or any other license agreement utilized in the Company’s research and development activities is terminated, if the Company fails to meet the obligations required under its arrangements, or if the Company is unable to successfully secure new strategic alliances or licensing agreements.

Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the acquisition date to be cash equivalents.

Marketable Securities

Effective January 1, 2023, the Company adopted ASU No. 2016-13 (“ASU 2016-13”), ASC 326, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments, using the effective date method. As the Company had never recorded any other-than-temporary-impairment adjustments to its available-for-sale debt securities prior to the effective date, no transition provisions were applicable to the Company.

Marketable securities represent holdings of available-for-sale marketable debt securities in accordance with the Company’s investment policy. The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. The Company classified all of its marketable securities as “available-for-sale” pursuant to ASC 320, Investments – Debt and Equity Securities. Investments not classified as cash equivalents are presented as either short-term or long-term investments based on both their maturities as well as the time period the Company intends to hold such securities. Available-for-sale securities are maintained by an investment manager and consist of U.S. Treasury securities and federal agency securities. Available-for-sale securities are carried at fair value with the unrealized gains and losses included in other comprehensive income (loss) as a component of stockholders’ equity (deficit) until realized. Any premium or discount arising at purchase is amortized or accreted to interest expense or income over the life of the instrument. Realized gains and losses are determined using the specific identification method and are included in other income (expense). There were no material realized gains or losses on marketable securities recognized during the years ended December 31, 2023 or 2022.

The Company assesses its available-for-sale debt securities under the available-for-sale debt security impairment model in ASC 326, Financial Instruments-Credit Losses, as of each reporting date in order to determine if a portion of any decline in fair value below carrying value recognized on its available-for-sale debt securities is the result of a credit loss. The Company records credit losses in the consolidated statements of operations and comprehensive loss as credit loss expense within other income (expense), net, which is limited to the difference between the fair value and the amortized cost of the security. To date, the Company has not recorded any credit losses on its available-for-sale debt securities.

Accrued interest receivable related to the Company’s available-for-sale debt securities is presented within prepaid expenses and other current assets on the Company’s consolidated balance sheets. The Company has elected the practical

expedient available to exclude accrued interest receivable from both the fair value and the amortized cost basis of available-for-sale debt securities for the purposes of identifying and measuring any impairment. The Company writes off accrued interest receivable once it has determined that the asset is not realizable. Any write offs of accrued interest receivable are recorded by reversing interest income, recognizing credit loss expense, or a combination of both. To date, the Company has not written off any accrued interest receivables associated with its marketable securities.

Fair Value Measurements

Certain assets of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

•

Level 1 — Quoted prices in active markets for identical assets or liabilities.

•

Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

•

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above (see Note 4). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows:


		Estimated Useful Life
Machinery and equipment		3 to 5 years
Furniture and fixtures		3 to 5 years
Leasehold improvements		Shorter of lease term of useful life

Costs for capital assets not yet placed into service are capitalized as construction-in-progress and depreciated in accordance with the above guidelines once placed into service. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is included in loss from operations. Expenditures for repairs and maintenance that do not improve or extend the life of the respective assets are charged to expense as incurred.

Impairment of Long-Lived Assets

Long-lived assets consist of property and equipment. The Company continually evaluates long-lived assets for potential impairment whenever events or changes in circumstances indicate that the carrying value of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares the carrying values of the asset group to the expected future undiscounted cash flows that the asset group is expected to generate from the use and eventual disposition of the long-lived asset group. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. If such asset group is considered to be impaired, the impairment loss to be recognized would be based on the excess of the carrying value of the impaired asset group over its fair value. The Company did not recognize any impairment losses on long-lived assets during the years ended December 31, 2023 and 2022.

Leases

Effective January 1, 2022, the Company adopted ASU No. 2016-02, Leases (Topic 842) (“ASC 842”) using the required modified retrospective approach and utilizing the effective date as its date of initial application.

The Company evaluates whether an arrangement is or contains a lease at the inception date. If determined to be or contain a lease, the Company determines the classification of the lease at the commencement date, which represents the date at which the lessor makes the underlying asset available for use by the Company. When determining the expected accounting lease term, the Company includes the noncancellable lease term, together with periods covered by (i) an option to extend the lease if the Company is reasonably certain to exercise such option, (ii) an option to terminate the lease if the Company is reasonably certain not to exercise such option and (iii) an option to extend or not terminate the lease where the exercise of such option is controlled by the lessor. The Company has elected the short-term lease exemption, which allows the Company to not recognize lease liabilities and right-of-use assets arising from lease arrangements with original lease terms of twelve months or less. The Company elected the practical expedient to not separate lease and non-lease components for its leases.

Right-of-use assets represent the Company’s right to use an underlying asset over the lease term and lease liabilities represent the Company’s obligation to make lease payments under the arrangement. The Company measures its lease liabilities as the present value of the lease payments, discounted using an incremental borrowing rate, as interest rates implicit in lease arrangements are generally not readily determinable. The Company measures its right-of-use assets as the present value of its lease payments at the commencement date. The incremental borrowing rate represents the interest rate at which the Company could borrow an amount equal to the lease payments on a fully collateralized basis, over a similar term, in a similar economic environment. The Company recognizes rent expense for operating leases on a straight-line basis. The Company recognizes variable lease expenses as incurred.

The Company remeasures right-of-use assets and lease liabilities when a lease is modified, and the modification is not accounted for as a separate contract. A modification is accounted for as a separate contract if the modification grants the Company an additional right of use not included in the original lease arrangement and the increase in lease payments is commensurate with the additional right of use. The Company assesses its right-of-use assets for impairment in a manner consistent with its assessment for long-lived assets held and used in operations.

Patent Costs

Costs to secure, defend and maintain patents, including those incurred in connection with filing and prosecuting patent applications, are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred for patent-related expenditures are classified as general and administrative expenses.

Segment Information

The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company is focused on the discovery, development and commercialization of antibody-based solutions for infectious diseases with pandemic potential. The Company’s chief operating decision maker reviews the Company’s financial information on an aggregated basis for purposes of assessing performance and allocating resources.

Research and Development Expenses

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including expenses incurred under agreements with external vendors and consultants engaged to perform nonclinical studies, preclinical studies and clinical trials as well as to manufacture research and development materials for use in such studies and trials and for commercial supply; salaries and related personnel costs; stock-based compensation; consultant fees; and third-party license fees.

Nonrefundable advance payments for goods and services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are delivered or the services are performed, or when it is no longer expected that the goods will be delivered or the services rendered.

Accrued Research and Development Costs

The Company has entered into various research, development and manufacturing contracts with third-party service providers, including clinical research organizations (“CROs”) and a contract manufacturing organization. With the exception of the Company’s commercial manufacturing arrangement with WuXi Biologics (Hong Kong) Limited (see Note 9), these agreements are generally cancellable. The Company recognizes research and development expense associated with such arrangements as the costs are incurred and records accruals for estimated ongoing research, development and manufacturing

costs, where necessary. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of outstanding obligations to those third parties as of period end. Any accrual estimates are based on a number of factors, including the Company’s knowledge of the progress towards completion of the specific tasks to be performed, invoicing to date under the contracts, communication from the vendors of any actual costs incurred during the period that have not yet been invoiced and the costs included in the contracts. Significant judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made by the Company. The historical accrual estimates made by the Company have not been materially different from the actual costs.

Asset Acquisitions and Acquired In-Process Research and Development Expenses

The Company measures and recognizes asset acquisitions that are not deemed to be business combinations based on the cost to acquire the asset or group of assets, which includes transaction costs. Goodwill is not recognized in asset acquisitions. In an asset acquisition, the cost allocated to acquire in-process research and development (“IPR&D”) with no alternative future use is recognized as expense on the acquisition date.

Contingent consideration in asset acquisitions payable in the form of cash is recognized in the period the triggering event is determined to be probable of occurrence and the related amount is reasonably estimable. Such amounts are expensed or capitalized based on the nature of the associated asset at the date the related contingency is resolved.

Stock-Based Compensation

The Company grants stock-based awards to employees, directors and non-employee consultants in the form of stock options to purchase shares of its common stock. The Company measures stock options with service-based vesting granted to employees, non-employees and directors based on the fair value on the date of grant using the Black-Scholes option-pricing model. The Company has primarily issued awards with service-based vesting conditions through December 31, 2023.

Compensation expense for awards granted to employees and directors for their service on the board of directors is recognized on a straight-line basis over the requisite service period of the respective award, which is generally the vesting period of the award. Compensation expense for awards granted to non-employees is recognized in the same period and manner as if the Company had paid cash for the goods or services provided, which is generally the vesting period of the award. The Company accounts for forfeitures of stock-based awards as they occur.

The Company classifies stock-based compensation expense in its statements of operations and comprehensive loss in the same manner in which the award recipient’s salary and related costs are classified or in which the award recipient’s service payments are classified.

Income Taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company 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 the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future profits expected and considering prudent and feasible tax planning strategies.

The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more likely than not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties. The Company had no amounts accrued for interest and penalties on its consolidated balance sheets as of December 31, 2023 and 2022.

Comprehensive Loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders. For the years ended December 31, 2023 and 2022, the Company's only element of other comprehensive loss was unrealized gains and losses on marketable securities.

Net Loss per Share

The Company follows the two-class method when computing net income (loss) per share attributable to common stockholders as the Company has issued shares that meet the definition of participating securities. The two-class method determines net income (loss) per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income (loss) for the period to be allocated between common and participating securities based upon their respective rights to share in the undistributed earnings as if all income (loss) for the period had been distributed. There is no allocation required under the two-class method during periods of loss since the participating securities do not have a contractual obligation to share in the losses of the Company.

Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding for the period, excluding shares of unvested restricted common stock. Diluted net income (loss) per share attributable to common stockholders is computed by adjusting net loss attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net income (loss) per share attributable to common stockholders is computed by dividing the diluted net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding for the period, including potential dilutive common shares. For the purposes of this calculation, the Company’s outstanding stock options and outstanding warrants are considered potential dilutive common shares.

The Company has generated a net loss for each of the periods presented. Accordingly, basic and diluted net loss per share attributable to common stockholders are the same because the inclusion of the potentially dilutive securities would be anti-dilutive.

Recently Issued and Adopted Accounting Pronouncements

The Company is an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and may remain an emerging growth company until the last day of the fiscal year following the fifth anniversary of the completion of its initial public offering. However, if certain events occur prior to the end of such five-year period, including if it becomes a “large accelerated filer,” its annual gross revenues exceeds $1.235 billion or it issues more than $1.0 billion of non-convertible debt in the previous three-year period, it will cease to be an emerging growth company prior to the end of such five-year period. For so long as the Company remains an emerging growth company, it is permitted and intends to rely on exemptions from certain disclosure requirements that are applicable to other public companies that are not emerging growth companies. For example, the JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. This allows an emerging growth company to delay the adoption of these accounting standards until they would otherwise apply to private companies.

On January 1, 2023, the Company adopted ASU No. 2016-13 (“ASU 2016-13”), Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. ASU 2016-13 requires measurement and recognition of expected credit losses for financial assets. In April 2019, the FASB issued clarification to ASU 2016-13 within ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, or ASU 2016-13. The guidance is effective for fiscal years beginning after December 15, 2022. The adoption of the standard was immaterial to the accompanying consolidated financial statements and related disclosures.

In December 2023, the FASB issued ASU 2023-09, Income Taxes—Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). ASU 2023-09 modifies the rules on income tax disclosures to enhance the transparency and decision-usefulness of income tax disclosures, particularly in the rate reconciliation table and disclosures about income taxes paid. The amendments are intended to address investors’ requests for income tax disclosures that provide more information to help them better understand an entity’s exposure to potential changes in tax laws and the ensuing risks and opportunities and to assess income tax information that affects cash flow forecasts and capital allocation decisions. The guidance also eliminates certain existing disclosure requirements related to uncertain tax positions and unrecognized deferred tax liabilities. The guidance is effective for all entities for annual periods beginning after December 15, 2025. All entities should apply the guidance prospectively but have the option to apply it retrospectively. Early adoption is permitted. The Company is continuing to assess the timing of adoption and the potential impacts of ASC 2023-09 on the consolidated financial statements and related disclosures.

Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts):


	2023			2022
Numerator:
Net loss attributable to common stockholders	$	(198,643	)	$	(241,317	)
Denominator:
Weighted-average common shares outstanding, basic and diluted		109,526,053			108,268,289
Net loss per share attributable to common stockholders, basic and diluted	$	(1.81	)	$	(2.23	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share


	2023		2022
Stock options to purchase common stock		23,065,514		23,239,391
Unvested restricted common stock		—		360,333
Warrants to purchase common stock		6,824,712		6,824,712
		29,890,226		30,424,436

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of Operating lease expense

The components of operating lease expense were as follows (in thousands):


	Year Ended December 31,
	2023		2022
Lease cost:
Operating lease cost	$	1,720	$	754
Variable lease cost		46		31
Total lease cost	$	1,766	$	785

Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows related to operating leases	$	1,731	$	837

Schedule of Future Minimum Payments Under Non-cancellable Purchase Obligations

Future minimum lease payments under the noncancelable leases as of December 31, 2023 was as follows (in thousands):


Year Ending December 31,	Operating Lease
2024		1,521
2025		430
2026		328
2027		—
Total lease payments		2,279
Present value adjustment		(114	)
Present value of operating lease liability	$	2,165

Commitments and Contingencies - Additional Information (Details) $ in Thousands				12 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 14, 2021 USD ($) ft²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Mar. 21, 2024 USD ($)	Nov. 30, 2022 USD ($)
Long Term Purchase Commitment [Line Items]
Lease term			5 years
Lease space \| ft²			9,600
Monthly rental payments	$ 1,300	$ 700	$ 400
borrowing rate				6.00%	6.00%
weighted-average remaining lease				1 year 9 months 18 days	2 years 7 months 6 days
Fees to be paid in cash							$ 3,000
Operating Lease, Liability, Current				$ 1,443	$ 1,559
Operating lease liabilities within twelve months				1,400
Operating Lease, Liability, Noncurrent				722	$ 2,165
Purchase Obligation				2,279
WuXi Commercial Manufacturing Services Agreement [Member]
Long Term Purchase Commitment [Line Items]
Future minimum payments under non-cancelable purchase obligations				24,100
Purchase Obligation				$ 33,900
PHP [Member]
Long Term Purchase Commitment [Line Items]
Fees to be paid in cash							$ 500
Subsequent Event [Member]
Long Term Purchase Commitment [Line Items]
Purchase Obligation						$ 50,300
Subsequent Event [Member] \| WuXi Commercial Manufacturing Services Agreement [Member]
Long Term Purchase Commitment [Line Items]
Purchase Obligation						$ 24,700

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows:


	Year Ended December 31,
	2023			2022
Federal statutory income tax rate		(21.0	)%		(21.0	)%
State income taxes, net of federal benefit		(11.0	)		(3.5	)
Federal research and development tax credits		(3.0	)		(4.1	)
Stock-based compensation		0.3			0.3
Change in deferred tax asset valuation allowance		34.8			28.3
Other		(0.1	)		—
Effective income tax rate		—	%		—	%

Summary of Net Deferred Tax Assets

The Company’s net deferred tax assets consisted of the following (in thousands):


	Year Ended December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	76,441		$	61,653
Capitalized research and development		74,115			36,550
Research and development tax credit carryforwards		24,313			16,901
Stock-based compensation expense		13,921			8,308
Warrant expense		4,781			4,066
Intangibles		4,217			2,602
Operating lease liabilities		569			871
Other		2,727			1,269
Total gross deferred tax assets		201,084			132,220
Valuation allowance		(200,385	)		(131,325	)
Total deferred tax assets	$	699		$	895
Deferred tax liabilities:
Operating lease right-of-use assets	$	(585	)	$	(884	)
Depreciation expense		(114	)		(11	)
Total deferred tax liabilities		(699	)		(895	)
Total net deferred tax assets	$	—		$	—

Population Health Partners

12 Months Ended

Dec. 31, 2023

Other Commitments [Abstract]

Population Health Partners

8. Population Health Partners

In November 2022 (the “PHP Effective Date”), the Company entered into a Master Services Agreement with Population Health Partners, L.P. (“PHP”), pursuant to which PHP agreed to provide services and create deliverables for the Company as agreed between the Company and PHP and set forth in one or more work orders under such agreement (the “PHP MSA”). The term of the PHP MSA commenced on the PHP Effective Date for an initial term of one year. The PHP MSA renews for subsequent periods, until terminated in accordance with its terms. On the PHP Effective Date, the Company and PHP entered into the first work order under the PHP MSA (the “PHP Work Order”), pursuant to which PHP agreed to advise and counsel the Company regarding clinical development and regulatory matters with respect to the Company’s product candidates. The PHP Work Order was effective for six months from the PHP Effective Date and terminated in accordance with its terms in May 2023. The PHP MSA contains customary confidentiality provisions and representations and warranties of the parties, as well as mutual non-solicitation of certain employees during the term of the PHP MSA and for a period of one year thereafter.

As compensation for the services and deliverables under the PHP Work Order, the Company paid PHP a cash fee of $0.5 million per month during the term of the PHP Work Order for an aggregate fee of $3.0 million (the “Aggregate Fee”).

During the years ended December 31, 2023 and 2022, the Company recognized $2.2 million and $0.8 million, respectively, of research and development expense related to the cash compensation paid to PHP. Please refer to Note 15 for additional information.

In addition to the cash compensation, on the PHP Effective Date, the Company issued a warrant to purchase shares of the Company’s common stock to PHP (the “PHP Warrant”). The exercise price of the PHP Warrant is $3.48 per share of the Company’s common stock, which was equal to the Nasdaq official closing price (as defined in the PHP Warrant) of a share of the Company’s common stock on the trading day immediately prior to the PHP Effective Date. The PHP Warrant is exercisable for up to an aggregate of 6,824,712 shares of the Company’s common stock, and vests in three separate tranches as follows:


	•		3,591,954 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization (as defined below) equals or exceeds $758,517,511 by November 15, 2028;


	•		1,795,977 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization equals or exceeds $1,137,776,266 by November 15, 2029; and


	•		1,436,781 shares of the Company’s common stock underlying the PHP Warrant vests if the Company’s Market Capitalization equals or exceeds $1,517,035,022 by November 15, 2030.

For purposes of the PHP Warrant, the term “Market Capitalization” means, with respect to a particular trading day, the total value of the outstanding shares of the Company’s common stock on such date, calculated by multiplying the Company’s volume weighted average price for the ten (10) trading days immediately preceding such date by the Company’s total number of outstanding shares of the Company’s common stock as reflected in (i) the Company’s most recent periodic or annual report filed with the U.S. Securities and Exchange Commission (“SEC”) (e.g., Annual Report on Form 10-K or Quarterly Report on Form 10-Q), as the case may be, (ii) a more recent public announcement by the Company or (iii) a more recent written notice by the Company or the Company’s transfer agent setting forth the number of shares of the Company's common stock outstanding.

The PHP Warrant is exercisable for ten years from the PHP Effective Date with respect to the vested portion(s) of the PHP Warrant. The PHP Warrant may be exercised by cash exercise or, at the election of PHP, by means of “cashless exercise” pursuant to a formula set forth in the PHP Warrant. The Company has also granted PHP certain “piggyback” registration rights requiring the Company to register any shares of the Company’s common stock underlying the PHP Warrant for resale with the SEC, subject to the Company’s existing obligations under that certain Second Amended and Restated Investors’ Rights Agreement, dated April 16, 2021, by and among the Company and the investors party thereto.

Upon the consummation of a fundamental transaction of the Company (as defined in the PHP Warrant) on or prior to November 15, 2028, all of the shares underlying the PHP Warrant would become immediately vested and exercisable; upon the consummation of a fundamental transaction of the Company after November 15, 2028 but on or prior to November 15, 2029, the shares underlying the second and third tranches of the PHP Warrant would become immediately vested and exercisable; and upon the consummation of a fundamental transaction of the Company after November 15, 2029 but on or prior to November 15, 2030, the shares underlying the third tranche of the PHP Warrant would become immediately vested and exercisable.

Refer to Note 11 for additional information on the PHP Warrant.

Clive Meanwell, M.D. and Tamsin Berry, members of the Company’s board of directors, are Managing Partner and Limited Partner of PHP, respectively.

Income Taxes - Summary of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 76,441	$ 61,653
Capitalized research and development	74,115	36,550
Research and development tax credits carryforwards	24,313	16,901
Stock-based compensation expense	13,921	8,308
Warrant expense	4,781	4,066
Intangibles	4,217	2,602
Operating lease liability	569	871
Other	2,727	1,269
Total gross deferred tax assets	201,084	132,220
Valuation allowance	(200,385)	(131,325)
Total deferred tax assets	699	895
Deferred tax liabilities:
Operating lease right-of-use assets	(585)	(884)
Depreciation expense	(114)	(11)
Total deferred tax liabilities	(699)	(895)
Total net deferred tax assets	$ 0	$ 0

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (PARENTHETICAL) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Research and Development Arrangement [Member]
Related party expenses	$ 8,418	$ 8,154
In Process Research and Development [Member]
Related party expenses	4,975	4,400
Warrant [Member]
Related party expenses	$ 0	$ 17,373

Income Taxes - Schedule of Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal statutory income tax rate	(21.00%)	(21.00%)
State income taxes, net of federal benefit	(11.00%)	(3.50%)
Federal research and development tax credits	(3.00%)	(4.10%)
Stock-based compensation	0.30%	0.30%
Change in deferred tax asset valuation allowance	34.80%	28.30%
Other	(0.10%)	0.00%
Effective income tax rate	0.00%	0.00%

Fair Value Measurements (Additional Information) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Transfers between level 3	$ 0	$ 0

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2023

Accrued Liabilities [Abstract]

Schedule of Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Accrued external research, development and manufacturing costs	$	28,151	$	13,955
Accrued professional and consultant fees		1,732		1,153
Accrued employee compensation		10,752		5,985
Other		225		818
	$	40,860	$	21,911

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Asset and Liabilities Measured at Fair Value on Recurring Basis

The following tables present the Company’s fair value hierarchy for its assets and liabilities that are measured at fair value on a recurring basis (in thousands):


	Fair Value Measurements at December 31, 2023:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	198,193	$	—	$	—	$	198,193
	$	198,193	$	—	$	—	$	198,193


	Fair Value Measurements at December 31, 2022:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	91,050	$	—	$	—	$	91,050
Marketable securities:
U.S. Treasury securities		107,871		—		—		107,871
Federal agency securities		—		172,044		—		172,044
	$	198,921	$	172,044	$	—	$	370,965

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (198,643)	$ (241,317)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 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 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/exampleRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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Reference 27: http://www.xbrl.org/2003/role/disclosureRef
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Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Defined Contribution Plan - Additional Information (Details) - 401(k) Plan [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Plan Disclosure [Line Items]
Percentage of eligible participants of non-elective contributions	3.00%
Defined contribution amount	$ 0.8	$ 0.8

Prepaid Expenses and Other Current Assets (Table)

12 Months Ended

Dec. 31, 2023

Prepaid Expense and Other Assets, Current [Abstract]

Summary of Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Prepaid external research, development and manufacturing costs	$	19,962	$	843
Prepaid insurance		1,770		2,392
Prepaid compensation and other		1,575		1,314
Interest receivable		933		377
	$	24,240	$	4,926

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

12. Income Taxes

During the years ended December 31, 2023 and 2022, the Company did not record income tax benefits for the net operating losses (“NOLs”) incurred or for the research and development tax credits generated in each period, due to its uncertainty of realizing a benefit from those items. All of the Company’s operating losses since inception have been generated in the U.S.

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows:


	Year Ended December 31,
	2023			2022
Federal statutory income tax rate		(21.0	)%		(21.0	)%
State income taxes, net of federal benefit		(11.0	)		(3.5	)
Federal research and development tax credits		(3.0	)		(4.1	)
Stock-based compensation		0.3			0.3
Change in deferred tax asset valuation allowance		34.8			28.3
Other		(0.1	)		—
Effective income tax rate		—	%		—	%

The Company’s net deferred tax assets consisted of the following (in thousands):


	Year Ended December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	76,441		$	61,653
Capitalized research and development		74,115			36,550
Research and development tax credit carryforwards		24,313			16,901
Stock-based compensation expense		13,921			8,308
Warrant expense		4,781			4,066
Intangibles		4,217			2,602
Operating lease liabilities		569			871
Other		2,727			1,269
Total gross deferred tax assets		201,084			132,220
Valuation allowance		(200,385	)		(131,325	)
Total deferred tax assets	$	699		$	895
Deferred tax liabilities:
Operating lease right-of-use assets	$	(585	)	$	(884	)
Depreciation expense		(114	)		(11	)
Total deferred tax liabilities		(699	)		(895	)
Total net deferred tax assets	$	—		$	—

As of December 31, 2023 and 2022, the Company had U.S. federal NOL carryforwards of $318.6 million and $263.7 million, respectively, which may be available to reduce future taxable income. All of the U.S. federal NOL carryforwards have an indefinite carryforward period but are limited in their usage to 80% of annual taxable income. In addition, as of December 31, 2023, the Company had state NOL carryforwards of $153.8 million, which may be available to reduce future taxable income, of which $9.6 million have an indefinite carryforward period while the remaining $144.2 million begin to expire in 2032. As of December 31, 2023, the Company also had U.S. federal and state research and development tax credit carryforwards of $19.3 million and $6.4 million, respectively, which may be available to reduce future tax liabilities and expire at various dates beginning in 2041 and 2036, respectively.

Utilization of the U.S. federal and state NOL carryforwards and research and development tax credit carryforwards may be subject to a substantial annual limitation under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, and corresponding provisions of state law, due to ownership changes that have occurred previously or that could occur in the future. These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income or tax liabilities. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain stockholders or public groups in the stock of a corporation by more than 50% over a three-year period. The Company has not conducted a study to assess whether a change of control has occurred or whether there have been multiple changes of control since inception due to the significant complexity and cost associated with such a study. If the Company has experienced a change of control, as defined by Section 382, at any time since inception, utilization of the NOL carryforwards or research and development tax credit carryforwards would be subject to an annual limitation under Section 382, which is determined by first multiplying the value of the Company’s stock at the time of the ownership change by the applicable long-term tax-exempt rate, and then could be subject to additional adjustments, as required. If a change in ownership were to have occurred during that period and resulted in the restriction of NOL or credit carryforwards, the reduction in the related deferred tax asset would be offset with a corresponding reduction in the valuation allowance.

The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company’s history of cumulative losses since inception, expectation of future losses and lack of other positive evidence and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance has been established against the net deferred tax assets as of December 31, 2023 and 2022. Management reevaluates the positive and negative evidence at each reporting period. During the years ended December 31, 2023 and 2022, the Company increased its valuation allowance by $69.1 million and $68.3 million, respectively, with such increase recognized as income tax expense, in order to maintain a full valuation allowance against its deferred tax assets, and there were no changes recorded to the allowance during the period.

The Company assesses uncertain tax positions in accordance with the guidance for accounting for uncertain tax positions. This pronouncement prescribes a recognition threshold and measurement methodology for recording within the consolidated financial statements uncertain tax positions taken, or expected to be taken, in the Company’s income tax returns. To the extent

the uncertain tax positions do not meet the “more likely than not” threshold, the Company derecognizes such positions. For tax positions meeting the “more likely than not" threshold, the Company measures and records the highest probable benefit, and establishes appropriate reserves for benefits that exceed the amount likely to be sustained upon examination. As of December 31, 2023 and 2022, the Company has not recorded any uncertain tax positions or related interest and penalties.

The Company files income tax returns in the U.S. federal and various state jurisdictions and is not currently under examination by any taxing authority for any open tax year. Due to NOL carryforwards, all years remain open for income tax examination. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the federal or state tax authorities to the extent utilized in a future period. No federal or state tax audits are currently in process.

- 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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-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-Based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

11. Stock-Based Compensation

2020 Equity Incentive Plan

The Company’s 2020 Equity Incentive Plan (the “2020 Plan”) provides for the Company to grant incentive stock options, non-qualified stock options, restricted stock awards, restricted stock units and other stock-based awards to employees, members of the board of directors and consultants. The 2020 Plan is administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The board of directors may also delegate to one or more officers of the Company the power to grant awards to employees and certain officers of the Company. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee or any such officer if so delegated.

The exercise price for stock options granted may not be less than the fair market value of the Company’s common stock on the date of grant, as determined by the board of directors, or at least 110% of the fair market value of the Company’s common stock on the date of grant in the case of an incentive stock option granted to an employee who owns stock representing more than 10% of the voting power of all classes of stock as determined by the board of directors as of the date of grant. Prior to the IPO, the Company’s board of directors determined the fair value of the Company’s common stock, taking into consideration its most recently available valuation of common stock performed by third parties as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the date of grant. Stock options granted under the 2020 Plan expire after ten years and typically vest over a four-year period with the first 25% vesting upon the first anniversary of a specified vesting commencement date and the remainder vesting in 36 equal monthly installments over the succeeding three years, contingent on the recipient’s continued employment or service. Certain awards of stock options permit the holders to exercise the option in whole or in part prior to the full vesting of the option in exchange for unvested shares of restricted common stock with respect to any unvested portion of the option so exercised.

As of December 31, 2023, there were 4,318,810 shares authorized to be issued upon the exercise of outstanding stock option grants and no shares reserved for future issuance under the 2020 Plan.

2021 Equity Incentive Plan

In July 2021, the Company’s board of directors adopted, and its stockholders approved, the 2021 Equity Incentive Plan (the “2021 Plan”), which became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company’s IPO. The 2021 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares reserved for issuance under the 2021 Plan was equal to 35,075,122, which is the sum of 11,413,572 new shares; plus the number of shares (not to exceed 23,661,550 shares), which represents (i) the number of shares that remained available for issuance under the 2020 Plan, at the time the 2021 Plan became effective, and (ii) any shares subject to outstanding stock options or other stock awards that were granted under the 2020 Plan that are forfeited, terminate, expire or are otherwise not issued. In addition, the number of shares of the Company’s common stock reserved for issuance under the 2021 Plan will automatically increase on the first day of each calendar year pursuant to the evergreen provision thereof, beginning on January 1, 2022 and continuing through January 1, 2031, in an amount equal to 5% of the shares of common stock outstanding on the last day of the calendar month before the date of each automatic increase, or a lesser number of shares determined by the board of directors. On January 1, 2022, 5,539,145 shares of common stock were automatically added to the shares authorized for issuance under the 2021 Plan pursuant to the evergreen provision thereof. The number of shares to be issued under the 2021

Plan did not increase on January 1, 2023 as determined by the Company’s board of directors. On January 1, 2024, 3,304,821 shares of common stock were added to the shares authorized for issuance under the 2021 Plan, pursuant to the evergreen provision thereof, as determined by the Company’s board of directors. The shares of common stock underlying any awards that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, repurchased or are otherwise terminated by the Company under the 2021 Plan will be added back to the shares of common stock available for issuance under the 2021 Plan.

As of December 31, 2023, there were an aggregate of 41,996,239 shares authorized to be issued under the 2020 Plan and the 2021 Plan, which included 4,318,810 and 18,746,704 shares authorized to be issued upon the exercise of outstanding stock option grants from the 2020 Plan and 2021 Plan, respectively, and 0 and 18,930,725 shares reserved for future issuance under the 2020 Plan and 2021 Plan, respectively.

Stock Option Valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. Prior to its IPO in August 2021, the Company had been a private company. Due to the proximity to the IPO, the Company continues to lack sufficient company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. For options with service-based vesting conditions, the expected term of the Company’s stock options has been determined utilizing the “simplified” method. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The following table presents, on a weighted-average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted:


	2023			2022
Expected term (in years)		5.9			6.0
Expected volatility		66.1	%		71.8	%
Risk-free interest rate		3.8	%		2.7	%
Expected dividend yield		—	%		—	%

Stock Option Activity

The following table summarizes the Company’s stock option activity since December 31, 2022:


	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
						(in years)		(in thousands)
Outstanding at December 31, 2022		23,239,391		$	7.01		7.9	$	1,594
Granted		9,862,389		$	2.36
Exercised		(1,224,330	)	$	0.78
Forfeited		(8,811,936	)	$	7.72
Outstanding at December 31, 2023		23,065,514		$	5.08		8.7	$	24,745
Vested and expected to vest at December 31, 2023		23,065,514		$	5.08		8.7	$	24,745
Options exercisable at December 31, 2023		7,371,263		$	7.30		8.0	$	5,195

The weighted-average grant date fair value of stock options granted during the year ended December 31, 2023 and 2022 was $1.46 and $2.79, respectively, per share.

The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair market value of the common stock for the options that had exercise prices lower than the estimated fair value of the Company’s common stock at December 31, 2023 and December 31, 2022.

The total intrinsic value of stock options exercised during the year ended December 31, 2023 and 2022 was $0.8 million and $1.0 million, respectively.

Early Exercise of Stock Options into Restricted Stock

The Company’s restricted stock activity during the year ended December 31, 2023 was solely due to shares of restricted common stock issued pursuant to the permitted early exercise of stock options as permitted under the 2020 Plan prior to amendments to the 2020 Plan. The 2021 Plan does not permit early exercise of stock options. Shares of common stock issued upon exercise of unvested stock options are restricted and continue to vest in accordance with the original vesting schedule applicable to the associated stock option award. The Company has the right to repurchase any unvested shares of restricted common stock, at the original purchase price, upon any voluntary or involuntary termination of the service relationship during the vesting period.

A summary of the Company’s unvested common stock from option early exercises that is subject to repurchase by the Company is as follows:


	Number of Shares
Unvested restricted stock at December 31, 2022		360,333
Issued		—
Vested		(75,166	)
Repurchased		(285,167	)
Unvested restricted stock at December 31, 2023		—

Proceeds from the early exercise of stock options are recorded as an early-exercise liability on the consolidated balance sheets. The liability for unvested common stock subject to repurchase is then reclassified to common stock and additional paid-in capital as the Company’s repurchase right lapses. Shares issued pursuant to the early exercise of stock options are not considered to be outstanding for accounting purposes until the shares vest. As of December 31, 2023, there were no unvested shares of restricted stock remaining and therefore the liability related to the payments was $0. As of December 31, 2022, the liability related to the payments for unvested shares from early-exercised options was less than $0.1 million.

Stock-Based Compensation Expense

The Company recorded stock-based compensation expense in the following expense categories of its consolidated statements of operations and comprehensive loss (in thousands):


	2023		2022
Research and development	$	6,240	$	12,800
Selling, general and administrative		12,445		8,848
	$	18,685	$	21,648

As of December 31, 2023, total unrecognized stock-based compensation expense related to unvested stock-based awards was $37.6 million, which is expected to be recognized over a weighted-average period of 2.5 years.

2021 Employee Stock Purchase Plan

In July 2021, the Company’s board of directors adopted, and its stockholders approved, the 2021 Employee Stock Purchase Plan (the “2021 ESPP”), which became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company’s IPO. A total of 1,342,773 shares of common stock were initially reserved for issuance under the 2021 ESPP. There were 290,996 shares issued under the 2021 ESPP as of December 31, 2023. The number of shares of common stock that may be issued under the 2021 ESPP will automatically increase on the first day of each calendar year, pursuant to the evergreen provision thereof, beginning on January 1, 2022 and continuing through January 1, 2031, by an amount equal to the lesser of (i) 1% of the shares of common stock outstanding on the last day of the calendar month before the date of each automatic increase, (ii) 2,685,546 shares and (iii) an amount determined by the Company’s board of directors. The number of shares to be issued under the 2021 ESPP did not increase on January 1, 2024 or January 1, 2023, pursuant to the evergreen provision thereof, as determined by the Company’s board of directors. The first offering under the 2021 ESPP was June 6, 2022. As of December 31, 2023, 1,051,777 shares remained available for issuance under the 2021 ESPP. During the year ended December 31, 2023, the Company recognized $0.1 million in related stock-based compensation expense.

Warrant Expense

In November 2022, the Company entered into the PHP MSA, the PHP Work Order and a warrant agreement with respect to the PHP Warrant. To compensate for the services and deliverables provided by PHP, the Company issued 6,824,712 equity-classified warrants to PHP. Each warrant shall give the right to acquire common stock of the Company at a purchase price of $3.48 per share. Per the agreement, the PHP Warrant is exercisable upon either the achievement of corresponding market capitalization targets or a consummation of a fundamental transaction (as defined in the PHP Warrant); as such, there are no other requirements, including any continuous service requirements, in order for PHP to be entitled to the PHP Warrant, if and when any portion of it vests.

There were no warrants issued during the year ended December 31, 2023. As of December 31, 2023, there were 6,824,712 warrants outstanding at a weighted average exercise price of $3.48, with a weighted-average remaining contractual term of 8.88 years.

Assumptions used to determine the fair value of PHP Warrant using the simulation model based on Geometric Brownian Motion in a risk-neutral framework are as follows:


	Year Ended December 31,
	2022
Weighted-average grant date fair value per warrant	$	2.55
Expected term (in years)		10.0
Expected volatility		70.0	%
Risk-free interest rate		3.8	%
Expected dividend yield		—	%
Common shares outstanding		108,982,401

The aggregate grant date fair value of the PHP Warrant was $17.4 million, which was recognized as warrant expense on the grant date in November 2022.

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2023	Mar. 12, 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	INVIVYD, INC.
Entity Central Index Key	0001832038
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	IVVD
Security Exchange Name	NASDAQ
Entity File Number	001-40703
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-1403134
Entity Address, Address Line One	1601 Trapelo Road
Entity Address, Address Line Two	Suite 178
Entity Address, City or Town	Waltham
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02451
City Area Code	781
Local Phone Number	819-0080
Document Annual Report	true
Document Transition Report	false
Entity Public Float			$ 67.1
Entity Common Stock, Shares Outstanding		119,221,230
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238
Auditor Location	Boston, Massachusetts
Documents Incorporated by Reference	Certain portions of the registrant’s definitive proxy statement for its 2024 Annual Meeting of Stockholders, which the registrant intends to file pursuant to Regulation 14A with the Securities and Exchange Commission no later than 120 days after the registrant’s fiscal year ended December 31, 2023, are incorporated by reference into Part III of this Annual Report on Form 10-K.

Marketable Securities - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Marketable Securities [Abstract]
Available for sale marketable securities	$ 0	$ 0

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	110,160,684	109,044,046
Common stock, shares outstanding	110,160,684	109,044,046

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Liabilities [Abstract]
Accrued external research, development and manufacturing costs	$ 28,151	$ 13,955
Accrued professional and consultant fees	1,732	1,153
Accrued employee compensation	10,752	5,985
Other	225	818
Accrued expenses	$ 40,860	$ 21,911

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

Operating expenses:

Research and development

^[1]

$ 158,658

$ 179,214

Acquired in-process research and development

^[2]

4,975

4,400

Selling, general and administrative

49,125

47,044

Warrant expense

^[3]

17,373

Total operating expenses

212,758

248,031

Loss from operations

(212,758)

(248,031)

Other income:

Other income, net

14,115

6,714

Total other income, net

14,115

6,714

Net loss

(198,643)

(241,317)

Other comprehensive income (loss)

Unrealized gain (loss) on available-for-sale securities, net of tax

259

(264)

Comprehensive loss

$ (198,384)

$ (241,581)

Net loss per share attributable to common stockholders, basic

$ (1.81)

$ (2.23)

Net loss per share attributable to common stockholders, diluted

$ (1.81)

$ (2.23)

Weighted-average common shares outstanding, diluted

109,526,053

108,268,289

Weighted-average common shares outstanding, basic

109,526,053

108,268,289

[1]	Includes related-party amounts of $8,418 and $8,154 for the years ended December 31, 2023 and 2022, respectively (see Note 15).
[2]	Includes related-party amounts of $4,975 and $4,400 for the years ended December 31, 2023 and 2022, respectively (see Note 15).
[3]	Includes related-party amounts of $0 and $17,373 for the years ended December 31, 2023 and 2022, respectively (see Note 15).

Convertible Preferred Stock - Additional Information (Details) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Preferred stock shares issued	0	0
Preferred stock per share	$ 0.0001	$ 0.0001
Common Stock, Shares, Issued	110,160,684	109,044,046
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Preferred stock shares outstanding	0	0

Marketable Securities

12 Months Ended

Dec. 31, 2023

Marketable Securities [Abstract]

Marketable Securities

3. Marketable Securities

Marketable securities held by the Company are classified as available-for-sale debt securities pursuant to ASC 320, Investments – Debt and Equity Securities, and carried at fair value in the accompanying consolidated balance sheets on a settlement date basis.

The Company did not hold any available-for-sale marketable securities as of December 31, 2023.

The following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of December 31, 2022 (in thousands):


December 31, 2022	Amortized Cost		Unrealized Gains		Unrealized Losses			Credit Losses		Fair Value
U.S. Treasury securities	$	107,973	$	13	$	(115	)	$	—	$	107,871
Federal agency securities		172,214		39		(209	)		—		172,044
Total financial assets	$	280,187	$	52	$	(324	)	$	—	$	279,915

No available-for-sale marketable securities held as of December 31, 2022 had remaining maturities greater than twelve months.

Stock-Based Compensation - Additional Information (Details)
$ / shares in Units, $ in Thousands

1 Months Ended

12 Months Ended

Jan. 01, 2024

Jan. 01, 2022

Nov. 30, 2022

USD ($)

$ / shares

Jul. 31, 2021

Jul. 31, 2020

Dec. 31, 2023

USD ($)

Installment

$ / shares

Dec. 31, 2022

USD ($)

$ / shares

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

2,685,546

Fair value of common stock | $ / shares

$ 1.46

$ 2.79

Liability for unvested shares | $

$ 0

Unrecognized stock based compensation expense | $

$ 37,600

Percentage of number of shares of common stock outstanding

1.00%

Unrecognized stock based compensation expense, Weighted average recognition period

2 years 6 months

Stock based compensation expense | $

$ 18,685

$ 21,648

Intrinsic value of stock options exercised | $

800

1,000

Warrant expense | $

^[1]

$ 0

17,373

Maximum [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Liability for unvested shares | $

$ 100

2020 Equity Incentive Plan [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

4,318,810

Shares available for future issuance

Grant exercise price, percentage of estimated fair value of common stock on date of grant (not less than)

110.00%

Combined voting power on all classes of stock threshold

10.00%

Percentage of options vesting

25.00%

Number of quarterly installments for vesting | Installment

Share-based payment award, expiration period

10 years

Award vesting period

4 years

Number of quarterly installments for vesting succeeding period

3 years

2021 Equity Incentive Plan [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

35,075,122

41,996,239

Shares available for future issuance

18,930,725

Issuance of common stock, shares

3,304,821

11,413,572

5,539,145

Percentage of number of shares of common stock outstanding

5.00%

2021 Equity Incentive Plan [Member] | Stock Options [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

18,746,704

2021 Equity Incentive Plan [Member] | Maximum [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Shares available for future issuance

23,661,550

2020 Employee Stock Purchase Plan Member

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Shares available for future issuance

2020 Employee Stock Purchase Plan Member | Stock Options [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

4,318,810

2021 Employee Stock Purchase Plan [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

1,342,773

290,996

Stock based compensation expense | $

$ 100

2022 Employee Stock Purchase Plan [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Number of shares of common stock authorized for issuance

1,051,777

PHP Warrants [Member]

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Issuance of common stock, shares

6,824,712

Purchase price per share | $ / shares

$ 3.48

Exercisable common stock

6,824,712

Exercise price | $ / shares

$ 3.48

Weighted-average remaining contractual term (Years)

8 years 10 months 17 days

Warrant expense | $

$ 17,400

[1]	Includes related-party amounts of $0 and $17,373 for the years ended December 31, 2023 and 2022, respectively (see Note 15).

Selected Quarterly Financial Data (unaudited) - Schedule of Quarterly Financial Information (Parenthetical) (Details) - shares	Dec. 31, 2023	Dec. 31, 2022
Common stock, shares issued	110,160,684	109,044,046
Common stock, shares outstanding	110,160,684	109,044,046

License and Collaboration Agreements

12 Months Ended

Dec. 31, 2023

License Agreement [Abstract]

License and Collaboration Agreements

7. License and Collaboration Agreements

Adimab Assignment Agreement

In July 2020, the Company entered into an Assignment and License Agreement with Adimab (the “Adimab Assignment Agreement”). Under the terms of the agreement, Adimab assigned to the Company all rights, title and interest in and to certain of its coronavirus-specific antibodies (each, a “CoV Antibody” and together, the “CoV Antibodies”), including modified or derivative forms thereof, and related intellectual property. In addition, Adimab granted to the Company a non-exclusive, worldwide, royalty-bearing, sublicensable license to certain of its platform patents and technology for the development, manufacture and commercialization of the CoV Antibodies and pharmaceutical products containing or comprising one or more CoV Antibodies (each, a “Product”) for all indications and uses, with the exception of certain diagnostic uses and use as a research reagent (the “Field”). The Company is entitled to sublicense the assigned rights and licensed intellectual property solely with respect to any CoV Antibody or Product, subject to specified conditions of the agreement. The Company is obligated to use commercially reasonable efforts to achieve specified development and regulatory milestones for Products in certain major markets and to commercialize a product in any country in which the Company obtains marketing approval.

Pursuant to the terms of the Adimab Assignment Agreement, the parties will establish one or more work plans that set forth the activities to be performed under the agreement (each, a “Work Plan”), and each party is responsible for performing the obligations to which it is assigned under such Work Plans. Upon execution of the Adimab Assignment Agreement, the Company and Adimab agreed on an initial Work Plan that outlined the services that will be performed commencing at inception of the arrangement. The Company is obligated to pay Adimab quarterly for its services performed under each Work Plan at a specified full-time equivalent rate. Otherwise, the Company is solely responsible for the development, manufacture and commercialization of the CoV Antibodies and associated Products at its own cost and expense. The Company is solely responsible for preparing and submitting all investigational new drug applications, new drug applications, biologics license applications and other regulatory filings for the CoV Antibodies and Products in the Field, and for obtaining and maintaining all marketing approvals for Products in the Field, at its sole expense. Additionally, the Company has the sole right to prosecute, maintain, enforce and defend patents covering the CoV Antibodies and Products, all at its own expense.

Amounts paid with respect to services performed by Adimab on the Company’s behalf under the Adimab Assignment Agreement are recognized as research and development expense as such amounts are incurred. During the years ended December 31, 2023 and 2022, the Company recognized $0 and $0.6 million, respectively, of research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab Assignment Agreement. Please refer to Note 15 for additional information.

The Company is obligated to pay Adimab up to $16.5 million upon the achievement of specified development and regulatory milestones for the first Product under the agreement that achieves such specified milestones and up to $8.1 million upon the achievement of specified development and regulatory milestones for the second Product under the agreement that achieves such specified milestones. The maximum aggregate amount of milestone payments payable under the agreement for any and all Products is $24.6 million, of which a total of $11.1 million has been achieved and paid as of December 31, 2023; however, milestone payments do not accrue for certain in vitro diagnostic devices consisting of or containing CoV Antibodies.

In March 2023, the Company achieved the first specified milestone for the second product candidate under the Adimab Assignment Agreement upon dosing of the first subject in a Phase 1 clinical trial evaluating VYD222, which obligated the Company to make a $0.4 million milestone payment to Adimab, which was paid in May 2023. In September 2023, the Company achieved specified milestones for the second product candidate under the Adimab Assignment Agreement upon dosing of the first subject in a pivotal clinical trial evaluating VYD222, which obligated the Company to make a $3.2 million milestone payment to Adimab, which was paid in October 2023. During the year ended December 31, 2023, the Company recognized $3.6 million of IPR&D expense with respect to contingent consideration payable under the Adimab Assignment Agreement. During the year ended December 31, 2022, the Company did not recognize any IPR&D expense in connection with contingent consideration payable under the Adimab Assignment Agreement. The next potential milestone under the Adimab Assignment Agreement is a low single-digit million-dollar regulatory milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of December 31, 2023.

The Company is obligated to pay Adimab royalties of a mid-single-digit percentage based on net sales of any Products, beginning upon the first commercial sale of a Product in accordance with the Adimab Assignment Agreement. The royalty rate is subject to reductions specified under the agreement. Royalties are due on a Product-by-Product and country-by-country basis beginning upon the first commercial sale of each Product and ending on the later of (i) 12 years after the first commercial sale of such Product in such country and (ii) the expiration of the last valid claim of a patent covering such Product in such country (the “Royalty Term”). In addition, the Company is obligated to pay Adimab royalties of a specified percentage in the range of 45% to 55% of any compulsory sublicense consideration received by the Company in lieu of certain royalty payments. Except for milestone payments of $11.1 million incurred through December 31, 2023, no other milestone, royalty or other contingent payments had become due to Adimab through December 31, 2023.

Unless earlier terminated, the Adimab Assignment Agreement remains in effect until the expiration of the last-to-expire Royalty Term for any and all Products. The Company may terminate the agreement at any time for any or no reason upon advance written notice to Adimab, or in the event of a material breach by Adimab that is not cured with specific periods. Adimab may only terminate the agreement for an uncured material breach by the Company for its due diligence obligation or a payment obligation. Upon any termination of the agreement prior to its expiration, all licenses and rights granted pursuant to the arrangement will automatically terminate and revert to the granting party and all other rights and obligations of the parties will terminate.

The Company concluded that the Adimab Assignment Agreement represented an asset acquisition of IPR&D assets with no alternative future use. The arrangement did not qualify as a business combination because substantially all of the fair value of the assets acquired was concentrated in a single asset.

Adimab Collaboration Agreement

In May 2021, the Company entered into a Collaboration Agreement with Adimab, as amended in November 2022 and September 2023 (the “Adimab Collaboration Agreement”), for the discovery and optimization of proprietary antibodies as potential therapeutic product candidates. Under the Adimab Collaboration Agreement, the Company and Adimab could collaborate on research programs for a specified number of targets selected by the Company within a specified time period. Under the Adimab Collaboration Agreement, Adimab granted the Company a worldwide, non-exclusive license to certain of its platform patents and technology and antibody patents to perform the Company’s responsibilities during the ongoing research period and for a specified evaluation period thereafter (the “Evaluation Term”). In addition, the Company granted Adimab a license to certain of the Company’s patents and intellectual property solely to perform Adimab’s responsibilities under the research plans. Under the Adimab Collaboration Agreement, the Company has an exclusive option, on a program-by-program basis, to obtain licenses and assignments to commercialize selected products containing or comprising antibodies directed against the applicable target, which option may be exercised upon the payment of a specified option fee for each program. Upon exercise of an option by the Company, Adimab will assign to the Company all right, title and interest in the antibodies of the optioned research program and will grant the Company a worldwide, royalty-free, fully paid-up, non-exclusive, sublicensable license under the Adimab platform technology for the development, manufacture and commercialization of the antibodies for which the Company has exercised its options and products containing or comprising those antibodies. The Company is obligated to use commercially reasonable efforts to develop, seek marketing approval for, and commercialize one product that contains an antibody discovered in each optioned research program.

The Company agreed to pay Adimab a quarterly fee of $1.3 million, which could be cancelled at the Company’s option at any time. For so long as the Company was paying such quarterly fee (or earlier if (i) the Company experiences a change of control after the third anniversary of the Adimab Collaboration Agreement or (ii) Adimab owns less than a specified percentage of the Company’s equity), Adimab and its affiliates agreed not to assist or direct certain third parties to discover or optimize antibodies intended to bind to coronaviruses or influenza viruses. Under the Adimab Collaboration Agreement, the Company could also elect to decrease the scope of Adimab’s exclusivity obligations and obtain a corresponding decrease in the quarterly fee. In December 2023, the Company elected to decrease the scope of Adimab’s exclusivity obligations to cover only coronaviruses, and obtained a corresponding decrease in the quarterly fee. Effective January 2024, the Company is obligated to pay Adimab a quarterly fee of $0.6 million. For each of the years ended December 31, 2023 and 2022, the Company recognized $5.2 million of research and development expense related to the quarterly fee.

For each agreed upon research program that is commenced, the Company is obligated to pay Adimab quarterly for its services performed during a given research program at a specified full-time equivalent rate; a discovery delivery fee of $0.2 million; and an optimization completion fee of $0.2 million. For each option exercised by the Company to commercialize a specific research program, the Company is obligated to pay Adimab an exercise fee of $1.0 million. Amounts paid with respect to services performed by Adimab on the Company’s behalf in each of the research programs under the Adimab Collaboration Agreement are recognized as research and development expense as such amounts are incurred and services are rendered. During the years ended December 31, 2023 and 2022, the Company recognized $0.5 million and $1.7 million, respectively, of research and development expense with respect to services performed by Adimab on the Company’s behalf under the Adimab Collaboration Agreement. During the year ended December 31, 2023, the Company recognized $1.0 million, $0.2 million, and $0.2 million of IPR&D expense related to an option exercise fee, a drug delivery fee and an optimization completion fee, respectively. During the year ended December 31, 2022, the Company recognized $1.0 million and $0.4 million of IPR&D expense related to an option exercise fee and a drug delivery fee, respectively. Please refer to Note 15 for additional information.

The Company is obligated to pay Adimab up to $18.0 million upon the achievement of specified development and regulatory milestones for each product under the Adimab Collaboration Agreement that achieves such milestones. The next potential milestone under the Adimab Collaboration Agreement is a low single-digit million dollar clinical milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of December 31, 2023. The Company is also obligated to pay Adimab royalties of a mid-single-digit percentage based on net sales of any product under the Adimab Collaboration Agreement, subject to reductions for third-party licenses. The royalty term will expire for each product on a country-by-country basis upon the later of (i) 12 years after the first commercial sale of such product in such country and (ii) the expiration of the last valid claim of any patent claiming composition of matter or method of making or using any antibody identified or optimized under the Adimab Collaboration Agreement in such country.

In addition, the Company is obligated to pay Adimab for Adimab’s performance of certain validation work with respect to certain antigens acquired from a third party. In consideration for this work, the Company is obligated to pay Adimab royalties of a low single-digit percentage based on net sales of products that contain such antigens for the same royalty term as antibody-based products, but the Company is not obligated to make any milestone payments for such antigen products. Through December 31, 2023, the Company had not paid any royalties to Adimab under the Adimab Collaboration Agreement.

The Adimab Collaboration Agreement will expire (i) if the Company does not exercise any option, upon the conclusion of the last Evaluation Term for the research programs, or (ii) if the Company exercises an option, on the expiration of the last royalty term for a product in a particular country, unless the agreement is earlier terminated. The Company may terminate the Adimab Collaboration Agreement at any time upon advance written notice to Adimab. In addition, subject to certain conditions, either party may terminate the Adimab Collaboration Agreement in the event of a material breach by the other party that is not cured within specified periods.

The Company concluded that the Adimab Collaboration Agreement represented an asset acquisition of IPR&D with no alternative future use. Therefore, payments made by the Company to Adimab for milestones achieved will be recognized as IPR&D expense in the related period in which the services are performed or the related milestone is considered probable of achievement. Amounts paid with respect to services performed by Adimab on the Company’s behalf under the Adimab

Collaboration Agreement are recognized as research and development expense as such amounts are incurred and services are rendered. Please refer to Note 15 for additional information.

Adimab Platform Transfer Agreement

In September 2022 (the “Adimab Platform Transfer Agreement Effective Date”), the Company entered into a Platform Transfer Agreement with Adimab (the “Adimab Platform Transfer Agreement”) under which the Company was granted the right under certain intellectual property of Adimab to practice certain elements of Adimab’s platform technology, including B-cell cloning using Adimab’s proprietary yeast cell lines and other antibody optimization libraries, trade secrets, protocols and software of Adimab, to discover, engineer and optimize antibodies. The Company does not have access to Adimab’s proprietary discovery libraries. The Company was also granted the right under certain intellectual property of Adimab to research, develop, make, sell and exploit such antibodies and products containing such antibodies. The Adimab platform has been transferred to the Company in accordance with the terms of the Adimab Platform Transfer Agreement. In September 2022, the Company recognized $3.0 million as IPR&D expense in connection with the upfront consideration payable for the rights assigned pursuant to the Adimab Platform Transfer Agreement.

The Company is obligated to pay Adimab an annual fee of single digit millions on each of the first four anniversaries of the Adimab Platform Transfer Agreement Effective Date, which allows the Company to receive material improvements to the platform technology, including materially improved antibody optimization libraries, updates that provide new functionality to the platform, and software upgrades, from Adimab through June 2027. The first annual fee became due in September 2023 and was paid in October 2023. During the year ended December 31, 2023, the Company recognized a portion of the first annual fee as research and development expense. Beginning in July 2027 and ending in June 2042, unless terminated earlier, the Company has the option to receive additional material improvements to the platform technology from Adimab, subject to a commercially reasonable fee to be negotiated by the parties.

The Company is obligated to pay Adimab up to $9.5 million upon the achievement of specified development and regulatory milestones for each product under the Adimab Platform Transfer Agreement that achieves such milestones. The next potential milestone under the Adimab Platform Transfer Agreement is a mid-six-digit dollar preclinical milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of December 31, 2023.

In addition, the Company is obligated to pay Adimab royalties of a low single-digit percentage based on net sales of products containing an antibody discovered, engineered or optimized using Adimab’s platform technology, subject to reductions specified under the Adimab Platform Transfer Agreement. Royalties are due on a product-by-product and country-by-country basis. The royalty term will expire for each product on a country-by-country basis upon the later of (i) 12 years after the first commercial sale of such product in such country and (ii) the expiration of the last valid claim of a program antibody patent for covering the program antibody contained in such product in such country. Through December 31, 2023, the Company had not paid any royalties to Adimab under the Adimab Platform Transfer Agreement.

The Company may terminate the Adimab Platform Transfer Agreement at any time upon advance written notice to Adimab. In addition, subject to certain conditions, either party may terminate the Adimab Platform Transfer Agreement in the event of a material breach by the other party that is not cured within specified periods or in connection with the other party’s insolvency.

The Company concluded that the Adimab Platform Transfer Agreement represented an asset acquisition of IPR&D with no alternative future use. Therefore, payments made by the Company to Adimab for milestones achieved will be recognized as IPR&D expense in the related period in which the services are performed or the related milestone is considered probable of achievement. Amounts paid with respect to the annual material improvement fees are recognized as research and development expense as such amounts are incurred. Please refer to Note 15 for additional information.

WuXi Biologics Cell Line License Agreement

In December 2020, as amended in February 2023 and March 2024, the Company entered into a Cell Line License Agreement with WuXi Biologics (Hong Kong) Limited (“WuXi Biologics”) (the “Cell Line License Agreement”), under which WuXi Biologics granted to the Company a non-exclusive, non-transferable, worldwide, royalty-bearing, sublicensable license to certain of its intellectual property, including certain patent rights associated with a proprietary cell line developed by WuXi Biologics for the exploitation of certain recombinant antibodies developed using such proprietary cell line (each, a “Licensed Product”). Each Licensed Product generated under the arrangement will be produced from a transformed or transfected version of the proprietary cell line derived by WuXi Biologics (each of such transformed or transfected cell lines, a “Licensed Cell Line”).

In December 2020, the Company recognized an upfront fee of $0.2 million upon completion of cell bank generation for the first Licensed Cell Line created under the Cell Line License Agreement. The Company is also obligated to pay royalties in the range of less than 1.0% to WuXi Biologics based on net sales of any Licensed Products manufactured by the Company or a third party on its behalf. However, if the Company uses WuXi Biologics to manufacture all of its commercial supplies for Licensed Products, no royalties would be owed by the Company to WuXi Biologics for net sales of Licensed Products. The Company has an option to buy out its royalty obligations on a Licensed Cell Line-by-Licensed Cell Line basis by making a one-time payment in the low eight-figures to WuXi Biologics. Royalties are due on a Licensed Product-by-Licensed Product basis commencing on the date of the first commercial sale of the applicable product and continuing for so long as the Company commercializes Licensed Products or, if earlier, until the Company exercises its option to buy out the royalty obligations. Through December 31, 2023, no royalties had become due to WuXi Biologics.

The Cell Line License Agreement remains in effect until it is terminated. The Company may terminate the Cell Line License Agreement at any time with notice to WuXi Biologics. WuXi Biologics may terminate the Cell Line License Agreement in the event the Company fails to make a payment when due under the Cell Line License Agreement and such non-payment is not cured within a specified period after notice. Either party may terminate the Cell Line License Agreement in the event of a material breach by the other party that is not cured within a specified period after notice. Upon termination of the Cell Line License Agreement, the license conveyed by WuXi Biologics to the Company will continue in full force and effect with respect to all Licensed Products manufactured using the Licensed Cell Line already generated under the Cell Line License Agreement, provided that the Company continues to pay its royalty obligations, if any.

The Company concluded that the Cell Line License Agreement represented an asset acquisition of IPR&D with no alternative future use. The Cell Line License Agreement did not qualify as a business combination because substantially all of the fair value of the assets acquired was concentrated in a single asset. The Company did not recognize any IPR&D expense under the Cell Line License Agreement during the years ended December 31, 2023 or 2022.

Research Collaboration and License Agreement with The Scripps Research Institute

In August 2021, the Company entered into a Research Collaboration and License Agreement (the “Research Agreement”) with The Scripps Research Institute (“TSRI”). Under the terms of the Research Agreement, TSRI performed research activities to identify vaccine candidates for the prevention, diagnosis or treatment of influenza or beta coronaviruses. In August 2021, the Company paid TSRI $1.5 million in funding, which was credited against research funding payable by the Company under the Research Agreement.

In April 2022, the Company provided written notice to TSRI to terminate the Research Agreement. Following early termination in the second quarter of 2022, all licenses were terminated and reverted to TSRI.

Amounts incurred for services performed by TSRI under the Research Agreement were expensed to research and development expense as the services were rendered. During the year ended December 31, 2023, the Company did not recognize any research and development expense with respect to services performed under the Research Agreement as it was terminated during 2022. During the year ended December 31, 2022, the Company recognized $1.7 million of research and development expense with respect to services performed under the Research Agreement.

Stock-Based Compensation - Schedule of Weighted Average Fair Value Assumptions in PHP Warrants (Details) - PHP Warrants [Member]	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average grant date fair value per warrant \| $ / shares	$ 2.55
Expected term (in years)	10 years
Expected volatility	70.00%
Risk-free interest rate	3.80%
Expected dividend yield	0.00%
Common shares outstanding \| shares	108,982,401

- Definition

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

+ References

+ Details

Net Loss per Share - Schedule of Earning Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Numerator:
Net Income (Loss)	$ (198,643)	$ (241,317)
Denominator:
Weighted-average common shares outstanding, basic	109,526,053	108,268,289
Weighted Average Number of Shares Outstanding, Diluted	109,526,053	108,268,289
Net loss per share attributable to common stockholders, basic	$ (1.81)	$ (2.23)
Net loss per share attributable to common stockholders, diluted	(1.81)	$ (2.23)
Granted	$ 2.36

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482635/260-10-55-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
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+ Details

- Definition

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

+ References

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+ Details

- Definition

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

+ References

+ Details

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Estimated Useful Life of Property and Equipment


		Estimated Useful Life
Machinery and equipment		3 to 5 years
Furniture and fixtures		3 to 5 years
Leasehold improvements		Shorter of lease term of useful life

Summary of Significant Accounting Policies - Summary of Estimated Useful Life of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2023
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Estimated Useful Lives	Shorter of lease term of useful life

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

4. Fair Value Measurements

The following tables present the Company’s fair value hierarchy for its assets and liabilities that are measured at fair value on a recurring basis (in thousands):


	Fair Value Measurements at December 31, 2023:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	198,193	$	—	$	—	$	198,193
	$	198,193	$	—	$	—	$	198,193


	Fair Value Measurements at December 31, 2022:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	91,050	$	—	$	—	$	91,050
Marketable securities:
U.S. Treasury securities		107,871		—		—		107,871
Federal agency securities		—		172,044		—		172,044
	$	198,921	$	172,044	$	—	$	370,965

The money market funds were valued by the Company based on quoted market prices, which represent a Level 1 measurement within the fair value hierarchy.

There were no changes to the valuation methods during the years ended December 31, 2023 or 2022.

The Company evaluates transfers between levels at the end of each reporting period. There were no transfers into or out of Level 1, Level 2 or Level 3 fair value measurements during the years ended December 31, 2023 or 2022.

- 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

Prepaid Expenses and Other Current Assets

12 Months Ended

Dec. 31, 2023

Prepaid Expense and Other Assets, Current [Abstract]

Prepaid Expenses Other Current Assets

5. Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Prepaid external research, development and manufacturing costs	$	19,962	$	843
Prepaid insurance		1,770		2,392
Prepaid compensation and other		1,575		1,314
Interest receivable		933		377
	$	24,240	$	4,926

Defined Contribution Plan	12 Months Ended
Defined Contribution Plan	Dec. 31, 2023
Retirement Benefits [Abstract]
Defined Contribution Plan	13. Defined Contribution Plan The Company maintains a 401(k) Plan (the “401(k) Plan”) for the benefit of eligible employees. The 401(k) Plan is a defined contribution plan under Section 401(k) of the Internal Revenue Code of 1986, as amended, that covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Pursuant to the terms of the 401(k) Plan, the Company is required to make non-elective contributions of 3% of eligible participants’ compensation. For both the years ended December 31, 2023 and 2022, the Company contributed $0.8 million to the 401(k) Plan.

Commitments and Contingencies - Schedule of operating lease expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lease cost
Operating lease cost	$ 1,720	$ 754
Variable lease cost	46	31
Total lease cost	1,766	785
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows related to operating leases	$ 1,731	$ 837

Selected Quarterly Financial Data (unaudited) - Schedule of Quarterly Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Selected Quarterly Financial Information [Abstract]
Net Income (Loss)	$ (198,643)	$ (241,317)

- Definition

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

+ References

+ Details

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Use of Estimates

Concentrations of Credit Risk, Significant Suppliers and License Rights

Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the acquisition date to be cash equivalents.

Marketable Securities

Fair Value Measurements

•

Level 1 — Quoted prices in active markets for identical assets or liabilities.

•

Property and Equipment


		Estimated Useful Life
Machinery and equipment		3 to 5 years
Furniture and fixtures		3 to 5 years
Leasehold improvements		Shorter of lease term of useful life

Impairment of Long-Lived Assets

Leases

Patent Costs

Segment Information

Research and Development Expenses

Accrued Research and Development Costs

Asset Acquisitions and Acquired In-Process Research and Development Expenses

Stock-Based Compensation

Income Taxes

Comprehensive Loss

Net Loss per Share

Recent Accounting Pronouncements

Recently Issued and Adopted Accounting Pronouncements

Fair Value Measurments - Asset and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Cash And Cash Equivalents [Member] \| Money Market Funds [Member]
Assets:
Asset fair value disclosure	$ 198,193
Recurring
Assets:
Asset fair value disclosure	198,193	$ 370,965
Recurring \| Money Market Funds [Member]
Assets:
Asset fair value disclosure		91,050
Recurring \| US Treasury Securities [Member]
Assets:
Asset fair value disclosure		107,871
Recurring \| Federal agency securities [Member]
Assets:
Asset fair value disclosure		172,044
Recurring \| Fair Value Level 1
Assets:
Asset fair value disclosure	198,193	198,921
Recurring \| Fair Value Level 1 \| US Treasury Securities [Member]
Assets:
Asset fair value disclosure		107,871
Recurring \| Fair Value Level 1 \| Federal agency securities [Member]
Assets:
Asset fair value disclosure
Recurring \| Fair Value Level 2
Assets:
Asset fair value disclosure	0	172,044
Recurring \| Fair Value Level 2 \| Money Market Funds [Member]
Assets:
Asset fair value disclosure		0
Recurring \| Fair Value Level 2 \| US Treasury Securities [Member]
Assets:
Asset fair value disclosure		0
Recurring \| Fair Value Level 2 \| Federal agency securities [Member]
Assets:
Asset fair value disclosure		172,044
Recurring \| Fair Value Level 3
Assets:
Asset fair value disclosure	0	0
Recurring \| Fair Value Level 3 \| Money Market Funds [Member]
Assets:
Asset fair value disclosure	0	0
Recurring \| Fair Value Level 3 \| US Treasury Securities [Member]
Assets:
Asset fair value disclosure		0
Recurring \| Fair Value Level 3 \| Federal agency securities [Member]
Assets:
Asset fair value disclosure
Recurring \| Cash And Cash Equivalents [Member] \| Fair Value Level 1 \| Money Market Funds [Member]
Assets:
Asset fair value disclosure	198,193	$ 91,050
Recurring \| Cash And Cash Equivalents [Member] \| Fair Value Level 2 \| Money Market Funds [Member]
Assets:
Asset fair value disclosure	$ 0

Nature of the Business and Basis of Presentation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 29, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Income (Loss)		$ (198,643)	$ (241,317)
Accumulated deficit		(732,069)	(533,426)
Proceeds from issuance of common stock		$ 240	$ 269
Sales Agreement [Member] \| Subsequent Event [Member]
Issuance of common stock, shares	9,000,000
Sale of stock, price per share	$ 4.5
Proceeds from issuance of common stock	$ 39,300

- Definition

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

+ References

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Summary of Significant Accounting Policies - Summary of the impact of the adoption (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Operating lease right-of-use asset	$ 2,229	$ 3,777
Operating lease liabilities, current	1,443	1,559
Other non-current liability	700	0
Operating lease liabilities, non-current	$ 722	$ 2,165

Accrued Expenses

12 Months Ended

Dec. 31, 2023

Accrued Liabilities [Abstract]

Accrued Expenses

6. Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Accrued external research, development and manufacturing costs	$	28,151	$	13,955
Accrued professional and consultant fees		1,732		1,153
Accrued employee compensation		10,752		5,985
Other		225		818
	$	40,860	$	21,911