0000950170-23-058166 | 10-Q | XBRL Viewer

Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The principal accounting policies applied in the preparation of these unaudited condensed consolidated financial statements are described in the Company’s audited financial statements as of and for the year ended December 31, 2022, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on February 28, 2023 (the “Annual Report on Form 10-K”). There have been no material changes in the Company’s significant accounting policies during the nine months ended September 30, 2023. Basis of Presentation The Company prepared its unaudited consolidated condensed financial statements in compliance with generally accepted accounting principles in the U.S. ("U.S. GAAP"). Any reference in these notes to applicable guidance is meant to refer to 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 unaudited condensed consolidated financial statements include the accounts of Merus N.V. and its wholly owned, controlled subsidiary, Merus US, Inc. All intercompany transactions and balances of subsidiaries have been eliminated in consolidation. In the opinion of management, these financial statements reflect all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the results for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the unaudited condensed consolidated financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The three months ended September 30, 2023 and 2022 are referred to as the third quarter of 2023 and 2022, respectively. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period. The unaudited condensed consolidated financial statements presented herein do not contain the required disclosures under U.S. GAAP for annual financial statements. Therefore, these unaudited condensed consolidated financial statements should be read in conjunction with the annual audited consolidated financial statements and related notes as of and for the year ended December 31, 2022, included in the Annual Report on Form 10-K. Going Concern At each reporting period, the Company evaluates whether there are conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company is required to make certain additional disclosures if it concludes substantial doubt exists and it is not alleviated by the Company’s plans or when its plans alleviate substantial doubt about the Company’s ability to continue as a going concern. The Company’s evaluation entails analyzing prospective operating budgets and forecasts for expectations of the Company’s cash needs, and comparing those needs to the current cash, cash equivalent and marketable security balances. After considering the Company’s current research and development plans and the timing expectations related to the progress of its clinical-stage programs and its plans to pursue commercialization of any antibody candidate, if approved, and after considering its existing cash, cash equivalents and marketable securities as of September 30, 2023, the Company did not identify conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year from the date these financial statements were issued. Additional details of the Company’s cash runway are described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations”. New Accounting Pronouncements The Company considers the applicability and impact of any recent Accounting Standards Update ("ASU") issued by the Financial Accounting Standards Board ("FASB"). Based on the assessment, the ASUs were determined to be either not applicable or are expected to have minimal impact on the Company's condensed consolidated financial statements.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2023

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

The principal accounting policies applied in the preparation of these unaudited condensed consolidated financial statements are described in the Company’s audited financial statements as of and for the year ended December 31, 2022, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on February 28, 2023 (the “Annual Report on Form 10-K”). There have been no material changes in the Company’s significant accounting policies during the nine months ended September 30, 2023.

Basis of Presentation

The Company prepared its unaudited consolidated condensed financial statements in compliance with generally accepted accounting principles in the U.S. ("U.S. GAAP"). Any reference in these notes to applicable guidance is meant to refer to 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 unaudited condensed consolidated financial statements include the accounts of Merus N.V. and its wholly owned, controlled subsidiary, Merus US, Inc. All intercompany transactions and balances of subsidiaries have been eliminated in consolidation. In the opinion of management, these financial statements reflect all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the results for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the unaudited condensed consolidated financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The three months ended September 30, 2023 and 2022 are referred to as the third quarter of 2023 and 2022, respectively. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period.

The unaudited condensed consolidated financial statements presented herein do not contain the required disclosures under U.S. GAAP for annual financial statements. Therefore, these unaudited condensed consolidated financial statements should be read in conjunction with the annual audited consolidated financial statements and related notes as of and for the year ended December 31, 2022, included in the Annual Report on Form 10-K.

Going Concern

At each reporting period, the Company evaluates whether there are conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company is required to make certain additional disclosures if it concludes substantial doubt exists and it is not alleviated by the Company’s plans or when its plans alleviate substantial doubt about the Company’s ability to continue as a going concern.

The Company’s evaluation entails analyzing prospective operating budgets and forecasts for expectations of the Company’s cash needs, and comparing those needs to the current cash, cash equivalent and marketable security balances. After considering the Company’s current research and development plans and the timing expectations related to the progress of its clinical-stage programs and its plans to pursue commercialization of any antibody candidate, if approved, and after considering its existing cash, cash

equivalents and marketable securities as of September 30, 2023, the Company did not identify conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year from the date these financial statements were issued. Additional details of the Company’s cash runway are described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations”.

New Accounting Pronouncements

The Company considers the applicability and impact of any recent Accounting Standards Update ("ASU") issued by the Financial Accounting Standards Board ("FASB"). Based on the assessment, the ASUs were determined to be either not applicable or are expected to have minimal impact on the Company's condensed consolidated financial statements.

Common Stock - Additional Information (Details)				1 Months Ended	3 Months Ended	12 Months Ended
Common Stock - Additional Information (Details)	Aug. 14, 2023 USD ($)	Aug. 09, 2023 $ / shares shares	May 22, 2023 USD ($)	May 31, 2021 USD ($)	Jun. 30, 2023 USD ($) shares	Dec. 31, 2022 USD ($)	Sep. 30, 2023 € / shares	Sep. 30, 2023 USD ($) shares	Aug. 09, 2023 € / shares	Dec. 31, 2022 € / shares	Dec. 31, 2022 USD ($) shares
Class of Stock [Line Items]
Common stock, value, issued								$ 5,874,000			$ 4,751,000
Common shares, issued \| shares								57,729,180			46,310,589
Common shares, par value \| € / shares							€ 0.09			€ 0.09
Sales Agreement
Class of Stock [Line Items]
Common shares, issued \| shares											2,720,846
Common shares, sold \| shares					3,272,280
Gross proceeds, before deducting sales agent commissions					$ 65,500,000	$ 59,500,000
Sales agent commissions						$ 1,700,000
Net proceeds, after deducting sales agent fees, underwriting discounts and commissions			$ 124,900,000		$ 63,800,000
Sales Agreement \| Maximum
Class of Stock [Line Items]
Stock sale agreement authorized amount			$ 125,000,000	$ 125,000,000
Underwriting commissions rate of gross proceeds of shares sold				3.00%
Underwriting Agreement
Class of Stock [Line Items]
Common shares, sold \| shares		6,818,182
Net proceeds, after deducting sales agent fees, underwriting discounts and commissions	$ 162,200,000
Sale of stock, price per share \| $ / shares		$ 22
Common shares, par value \| € / shares									€ 0.09
Additional common shares at public offering price \| shares		1,022,727

Supplemental Balance Sheet Information

9 Months Ended

Sep. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Supplemental Balance Sheet Information

4. Supplemental Balance Sheet Information

Prepaid expenses and other current assets consisted of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Prepaid research and development expenses	$	4,296	$	6,372
Prepaid general and administrative expenses		5,960		2,940
Interest receivable		1,173		647
Other		1,399		2,204
Total	$	12,828	$	12,163

Accrued expenses and other liabilities consisted of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Accrued research and development expenses	$	27,760	$	26,159
Accrued personnel costs		5,145		5,778
Accrued general and administrative expenses		2,734		3,615
Other		73		38
Total	$	35,712	$	35,590

Overview	9 Months Ended
Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Overview	1. Overview Merus N.V. is a clinical-stage oncology company developing innovative antibody therapeutics, headquartered in Utrecht, the Netherlands. Merus US, Inc. is a wholly-owned subsidiary of Merus N.V. located at 139 Main Street, Cambridge, Massachusetts, United States (collectively, the “Company”). Since inception, the Company has generated an accumulated deficit of $692.9 million as of September 30, 2023. The Company expects to continue to incur significant expenses and operating losses for the foreseeable future as its antibody candidates advance through discovery, pre-clinical development and clinical trials and as it seeks regulatory approval and pursues commercialization of any approved antibody candidate. As a result, the Company may need additional financing to support its continuing operations. Until the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operations through public equity offerings, debt financings, or other sources, which may include collaborations, business development and licensing opportunities with third parties. Adequate additional financing may not be available to the Company on acceptable terms, or at all. The Company’s inability to raise capital as and when needed would have a negative impact on its financial condition and ability to pursue its business strategy. The Company will need to generate significant revenues to achieve profitability and may never do so.

Overview

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Overview

1. Overview

Merus N.V. is a clinical-stage oncology company developing innovative antibody therapeutics, headquartered in Utrecht, the Netherlands. Merus US, Inc. is a wholly-owned subsidiary of Merus N.V. located at 139 Main Street, Cambridge, Massachusetts, United States (collectively, the “Company”).

Since inception, the Company has generated an accumulated deficit of $692.9 million as of September 30, 2023. The Company expects to continue to incur significant expenses and operating losses for the foreseeable future as its antibody candidates advance through discovery, pre-clinical development and clinical trials and as it seeks regulatory approval and pursues commercialization of any approved antibody candidate.

As a result, the Company may need additional financing to support its continuing operations. Until the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operations through public equity offerings, debt financings, or other sources, which may include collaborations, business development and licensing opportunities with third parties. Adequate additional financing may not be available to the Company on acceptable terms, or at all. The Company’s inability to raise capital as and when needed would have a negative impact on its financial condition and ability to pursue its business strategy. The Company will need to generate significant revenues to achieve profitability and may never do so.

Employee Benefits - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended			9 Months Ended	12 Months Ended
	Apr. 30, 2020	Sep. 30, 2023	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2023	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value of options granted					$ 11.67
Share-based payment award, fair value assumptions, method used					Black Scholes option pricing model
Number of options granted					2,625,427
Severance payment						$ 100,000
Additional compensation cost				$ 200,000
Net gain associated with the derivative instrument		$ 0	$ 400,000
Derivative, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration]			Nonoperating Income (Expense)
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Net reversal of stock-based compensation expense						$ 400,000
Postemployment Retirement Benefits
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Executive settlements, cash compensation paid	$ 300,000

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Public Offerings, Net of Underwriting Discounts and Commissions and Offering Cost [Member]	Common Stock [Member]	Common Stock [Member] Public Offerings, Net of Underwriting Discounts and Commissions and Offering Cost [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] Public Offerings, Net of Underwriting Discounts and Commissions and Offering Cost [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2021	$ 316,201		$ 4,481		$ 787,869		$ (466,928)	$ (9,221)
Beginning balance, shares at Dec. 31, 2021			43,467,052
Exercise of stock options and vesting of restricted stock units	879		$ 8		871
Exercise of stock options and vesting of restricted stock units, shares			82,273
Stock-based compensation	5,334				5,334
Currency translation adjustment	(6,048)							(6,048)
Net loss	(18,893)						(18,893)
Ending balance at Mar. 31, 2022	297,473		$ 4,489		794,074		(485,821)	(15,269)
Ending balance, shares at Mar. 31, 2022			43,549,325
Beginning balance at Dec. 31, 2021	316,201		$ 4,481		787,869		(466,928)	(9,221)
Beginning balance, shares at Dec. 31, 2021			43,467,052
Currency translation adjustment	(45,444)
Net loss	(49,222)
Ending balance at Sep. 30, 2022	298,777		$ 4,750		864,842		(516,150)	(54,665)
Ending balance, shares at Sep. 30, 2022			46,302,877
Beginning balance at Mar. 31, 2022	297,473		$ 4,489		794,074		(485,821)	(15,269)
Beginning balance, shares at Mar. 31, 2022			43,549,325
Issuance of common stock		$ 47,925		$ 220		$ 47,705
Issuance of common stock, shares				2,298,906
Exercise of stock options and vesting of restricted stock units	184		$ 2		182
Exercise of stock options and vesting of restricted stock units, shares			18,589
Stock-based compensation	6,662				6,662
Currency translation adjustment	(19,921)							(19,921)
Net loss	(5,714)						(5,714)
Ending balance at Jun. 30, 2022	326,609		$ 4,711		848,623		(491,535)	(35,190)
Ending balance, shares at Jun. 30, 2022			45,866,820
Issuance of common stock		9,583		$ 38		9,545
Issuance of common stock, shares				421,940
Exercise of stock options and vesting of restricted stock units	150		$ 1		149
Exercise of stock options and vesting of restricted stock units, shares			14,117
Stock-based compensation	6,525				6,525
Currency translation adjustment	(19,475)							(19,475)
Net loss	(24,615)						(24,615)
Ending balance at Sep. 30, 2022	298,777		$ 4,750		864,842		(516,150)	(54,665)
Ending balance, shares at Sep. 30, 2022			46,302,877
Beginning balance at Dec. 31, 2022	247,055		$ 4,751		870,874		(598,122)	(30,448)
Beginning balance, shares at Dec. 31, 2022			46,310,589
Exercise of stock options and vesting of restricted stock units	217		$ 3		214
Exercise of stock options and vesting of restricted stock units, shares			30,592
Stock-based compensation	5,750				5,750
Currency translation adjustment	4,242							4,242
Net loss	(39,741)						(39,741)
Ending balance at Mar. 31, 2023	217,523		$ 4,754		876,838		(637,863)	(26,206)
Ending balance, shares at Mar. 31, 2023			46,341,181
Beginning balance at Dec. 31, 2022	247,055		$ 4,751		870,874		(598,122)	(30,448)
Beginning balance, shares at Dec. 31, 2022			46,310,589
Currency translation adjustment	(6,985)
Net loss	(94,786)
Ending balance at Sep. 30, 2023	393,388		$ 5,874		1,117,855		(692,908)	(37,433)
Ending balance, shares at Sep. 30, 2023			57,729,180
Beginning balance at Mar. 31, 2023	217,523		$ 4,754		876,838		(637,863)	(26,206)
Beginning balance, shares at Mar. 31, 2023			46,341,181
Issuance of common stock		63,719		$ 322		63,397
Issuance of common stock, shares				3,272,280
Exercise of stock options and vesting of restricted stock units	2,248		$ 23		2,225
Exercise of stock options and vesting of restricted stock units, shares			240,198
Stock-based compensation	6,453				6,453
Currency translation adjustment	(505)							(505)
Net loss	(32,033)						(32,033)
Ending balance at Jun. 30, 2023	257,405		$ 5,099		948,913		(669,896)	(26,711)
Ending balance, shares at Jun. 30, 2023			49,853,659
Issuance of common stock		$ 161,783		$ 771		$ 161,012
Issuance of common stock, shares				7,840,909
Exercise of stock options and vesting of restricted stock units	619		$ 4		615
Exercise of stock options and vesting of restricted stock units, shares			34,612
Stock-based compensation	7,315				7,315
Currency translation adjustment	(10,722)							(10,722)
Net loss	(23,012)						(23,012)
Ending balance at Sep. 30, 2023	$ 393,388		$ 5,874		$ 1,117,855		$ (692,908)	$ (37,433)
Ending balance, shares at Sep. 30, 2023			57,729,180

- Definition

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

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+ Details

- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

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+ Details

Investments in Debt Securities

9 Months Ended

Sep. 30, 2023

Debt Securities [Abstract]

Investments in Debt Securities

3. Investments in Debt Securities

The following tables summarize the Company’s investments in debt securities and their presentation in the condensed consolidated balance sheet:


	September 30, 2023		December 31, 2022
	(in thousands)
Money market funds	$	20,499	$	18,404
Corporate paper and notes		134,511		126,102
U.S. government agency securities		52,669		34,364
U.S. treasuries		21,482		18,471
Total	$	229,161	$	197,341

Fair value of debt securities	$	228,314	$	196,345


	September 30, 2023		December 31, 2022
	(in thousands)
Cash equivalents	$	25,200	$	18,404
Current marketable securities		146,702		142,480
Non-current marketable securities		57,259		36,457
Total	$	229,161	$	197,341

The Company does not intend to sell and it is unlikely that the Company will be required to sell the above investments before recovery of their amortized cost bases, which may be at maturity. The Company determined that there was no material change in the credit risk of any of its investments.

The fair value of money market funds is determined based on publicly available market price for these funds (Level 1). The fair value of other debt securities is determined based on the publicly available inputs which includes a market price for the same or similar instruments adjusted for estimates in interest yield (Level 2).

Income Taxes

9 Months Ended

Sep. 30, 2023

Income Tax Disclosure [Abstract]

Income Taxes

5. Income Taxes

The Company files income tax returns in the U.S. federal and Massachusetts jurisdictions as well as in the Netherlands. The components of the income tax expense (benefit) from continuing operations are as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2023			2022			2023		2022
	(In thousands)						(In thousands)
U.S. federal	$	(871	)	$	370		$	580	$	420
U.S. state		(366	)		152			235		171
Total current income tax benefit	$	(1,237	)	$	522		$	815	$	591

U.S. federal	$	1,665		$	(137	)	$	947	$	(13	)
U.S. state		690			(58	)		393		(6	)
Total deferred income tax expense (benefit)	$	2,355		$	(195	)	$	1,340	$	(19	)

Total income tax expense (benefit)	$	1,118		$	327		$	2,155	$	572

After consideration of all positive and negative evidence, we believe that it is more-likely-than-not that the Netherlands deferred tax assets, that are not supported by reversing temporary differences, will not be realized. As a result, we established a full valuation allowance against deferred tax assets of the Netherlands.

Under Dutch tax law, net operating loss carryforwards may be used to offset future taxable income in full up to €1.0 million and 50% of taxable income that exceeds €1.0 million. Effective as of January 1, 2022, these losses can be carried forward indefinitely.

- 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

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-Topic 946
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-Section 50
-Paragraph 13
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+ Details

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - € / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common shares, par value	€ 0.09	€ 0.09
Common shares, authorized	67,500,000	67,500,000
Common shares, issued	57,729,180	46,310,589
Common shares, outstanding	57,729,180	46,310,589

Income Taxes - Summary of Components of Expense for (Benefit) from Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
U.S. federal	$ (871)	$ 370	$ 580	$ 420
U.S. state	(366)	152	235	171
Total current income tax benefit	(1,237)	522	815	591
U.S. federal	1,665	(137)	947	(13)
U.S. state	690	(58)	393	(6)
Total deferred income tax expense (benefit)	2,355	(195)	1,340	(19)
Total income tax expense (benefit)	$ 1,118	$ 327	$ 2,155	$ 572

- Definition

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

+ References + Details

Leases - Summary of Components of Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Lease cost
Operating lease cost	$ 517	$ 701	$ 1,743	$ 1,816
Variable lease cost	53	83	137	282
Total lease cost included in operating expenses	570	784	1,880	2,098
Other information
Cash paid for amounts included in the measurement of lease liabilities included in operating cash flows	$ 544	$ 733	$ 1,828	$ 1,881

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (23,012)	$ (32,033)	$ (39,741)	$ (24,615)	$ (5,714)	$ (18,893)	$ (94,786)	$ (49,222)

- Definition

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

+ References

+ Details

Collaborations

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Collaborations

8. Collaborations

Lilly

On January 18, 2021, Eli Lilly and Company (“Lilly”) agreed to pay the Company a $40.0 million, non-refundable upfront payment, and purchased 706,834 common shares at a stated price per share of $28.295, for an aggregate purchase price of $20.0 million. The Company and Lilly agreed to collaborate with respect to the discovery and research of bispecific antibodies utilizing the Company’s proprietary Biclonics® bispecific technology platform. The collaboration encompasses up to three (3) independent programs directed to the generation of T-cell re-directing bispecific antibodies that bind CD3 and a tumor associated antigen target selected by Lilly to be the subject of each program.

The objective of each program is to develop a lead compound that Lilly would be able to continue to develop through clinical trials. Lilly agreed to fund the research activities the Company conducts for each program under an agreed research plan and budget. Lilly receives an exclusive, worldwide, royalty-bearing, sublicensable license, under certain patent rights and know-how to exploit certain compounds and products directed to designated targets in combination with targeting CD3, or directed to such designated target(s) alone as a monospecific antibody or monospecific antibody drug conjugate, subject to rights granted by Merus to third parties under one or more existing third party agreements. Merus retains all rights not granted to Lilly. Lilly has certain rights to replace selected targets, including the right to substitute a target selection after initial selection for a period of time. The Company may be entitled to further milestones and royalties in the future dependent on development and commercialization of any resulting product.

The initial term of the arrangement includes a three-year research term for the Company to perform research and development activities, subject to two extension terms of six months at Lilly’s discretion. While the arrangement may be terminated in its entirety or on a program-by-program basis at will by Lilly, there are no direct costs or penalties to Lilly to terminate the arrangement prior to the end of the initial term.

At inception of the arrangement, the Company identified a single performance obligation comprised of a combined delivery of a license and related activities, including research activities associated with a product candidate against the first target and the activities of the joint steering committee. The Company also identified two other combined performance obligations relating to options exercisable by Lilly to select a second and third target to advance a second and third product candidate against the selected targets through discovery and research.

The transaction price at inception was comprised of fixed consideration of $43.5 million that was derived from the $40.0 million upfront payment and $20.0 million share purchase proceeds, net of the fair value of shares of the shares delivered to Lilly of $16.5 million, and variable consideration associated with the funding of research services for the product candidate against the first target at inception. All other consideration under the arrangement was determined to be variable consideration and fully constrained at inception.

The fixed consideration was allocated equally amongst the three performance obligations and the variable consideration associated with each target was allocated to the performance obligation of each respective target. The equal allocation of the fixed consideration was based on the estimated standalone selling price of each performance obligation as each was materially the same.

On February 12, 2021, the Company and Lilly completed the initial exchange of fixed consideration and transfer of common shares. The Company initially deferred $43.5 million allocated to the performance obligations to be recognized as revenue over time using a cost-to-cost measure of progress toward the development of a lead compound for each respective target, anticipated to be recognized as revenue within the initial research term, along with research funding. Development milestones, commercialization milestones and royalties are variable consideration, fully constrained, to be included in the transaction price for each performance obligation and recognized in future periods in accordance with the Company’s revenue recognition policy. The revenue recognized relating to each combined performance obligation is presented in the notes according to the source of consideration received (upfront, reimbursement revenue, milestone), reflective of their differing timing of receipt.

During the year ended December 31, 2022, Lilly substituted one of the target programs. The program timeline is expected to extend beyond the original research term. Under the current research plan, for the program to be completed in collaboration with Merus, Lilly would be required to extend the research term to 2025, subject to its discretion. Lilly exercised the first six month extension in October 2023. The program timeline is expected to extend beyond this first extension, and such an extension into 2025 would result in a fee of $0.5 million. As a result of the program substitution in 2022, the Company increased the transaction price for one of the programs by $0.5 million during the year ended December 31, 2022.

As of September 30, 2023, research activities were on-going, and no milestones have been achieved.

Incyte

On January 23, 2017, the Company completed the sale of shares and exchange of a license with Incyte Corporation (“Incyte”). The Company initially deferred $152.6 million of the transaction price allocated to the license and related performance obligation as deferred revenue, to be recognized as revenue over time as the primary benefit of the license to Incyte is access to the Company’s intellectual property covering its Biclonics® technology platform for the generation of potential product candidates. Development milestones, commercialization milestones and royalties are variable consideration, fully constrained, to be recognized in future periods in accordance with the Company’s revenue recognition policy. Cost reimbursements for research services are recognized as they are performed over time as these are considered a separate performance obligation.

In January 2022, the Company announced that Incyte elected to opt-out of its ex-U.S. development of MCLA-145, from the parties joint collaboration agreement executed in 2017. At inception of the collaboration, for the designated product candidate (MCLA-145), the Company retained the exclusive right to develop and commercialize products and product candidates in the United States, while Incyte obtained the exclusive right to develop and commercialize products and product candidates arising from such program outside the United States. For MCLA-145, the parties conducted and shared equally the costs of mutually agreed global development activities. Incyte’s opt-out of ex-U.S. rights to MCLA-145 provides the Company the exclusive right to develop and commercialize potential MCLA-145 products globally. Under the collaboration, Incyte continued to support the program for a limited time while ex-U.S. activities transitioned to the Company. Incyte will retain a right to a residual royalty of up to 4% on sales of future commercialization of MCLA-145, if approved.

During the three months ended September 30, 2023, the Company recognized a $2.5 million milestone from Incyte related to the initiation of a Phase 1 study with respect to a novel target pair program and a $1.0 million milestone from Incyte related to candidate nomination. During the nine months ended September 30, 2023, the Company has recognized $6.0 million in milestones from Incyte.

Ono

In April 2014, the Company granted Ono Pharmaceutical Co., Ltd. (“Ono”) an exclusive, worldwide, royalty-bearing license, with the right to sublicense, research, test, make, use and market a limited number of bispecific antibody candidates based on the Company’s Biclonics® technology platform against two undisclosed targets directed to a particular undisclosed target combination.

On March 14, 2018, the Company granted Ono an exclusive, worldwide, royalty-bearing license, with the right to sublicense, research, test, make, use and market a limited number of bispecific antibody candidates based on the Company’s Biclonics® technology platform against two undisclosed targets directed to a particular undisclosed target combination. Ono agreed to pay the Company an upfront, non-refundable payment of €0.7 million. In addition, the Company was entitled to €0.3 million intended to compensate the Company for research services already completed upon entering into the agreement, and €0.2 million to be paid to the Company over time for full-time equivalent funding. The Company is entitled to research and development milestones in addition to potential royalties on future sales of any bispecific antibody candidate that may be approved. The Company identified performance obligations for: (1) provision of a license for the target combination, and (2) research and development services. The Company concluded that Ono would be able to develop and benefit from the license, independent of the research and development services. Certain of the research and development services are capable of being performed by third parties with an appropriate sub-license, and are recognized over time as these services are delivered. Milestone payments are fully constrained as variable consideration to be recognized in future periods in accordance with the Company’s revenue recognition policy.

Amounts related to the provision of the licenses were amortized over the intended period of use. There were no development or commercialization milestones achieved during the three months or nine months ended September 30, 2023.

Simcere

In January 2018, the Company granted Simcere Pharmaceuticals Group (“Simcere”) an exclusive license to develop and commercialize up to three bispecific antibodies in China to be produced by Merus utilizing the Company’s Biclonics® technology platform (the “Simcere Agreement”). The Company received an upfront, non-refundable payment of $2.75 million, relating to three separate research programs.

At inception of the arrangement, the Company identified three performance obligations comprised of the combined delivery of a license and performance of research and development activities with respect to each program. The Company performed research and development activities to achieve candidate nomination. The Company concluded that these activities were not distinct from the underlying license for each program as Simcere would not be able to benefit from the license apart from research and development activities at this phase of development.

The transaction price under the arrangement comprised fixed consideration of $2.75 million. The transaction price was allocated to each separate performance obligation on a relative standalone fair value basis. The Company deferred the portion of the upfront payment allocated to the three performance obligations as deferred revenue, to be recognized over time. Compensation for research and development services prior to candidate nomination are allocated to each program performance obligation and also recognized over time. Development milestone payments allocated to each of the program performance obligations are constrained as variable consideration to be recognized in future periods in accordance with the Company’s revenue recognition policy.

The Company has achieved three milestones under this agreement and has received an aggregate of $1.8 million in milestone payments. In January 2022, the Company and Simcere terminated the Simcere Agreement, effective March 30, 2022.

Contract Assets and Liabilities

The following tables provide amounts by year indicated and by line item included in the Company's accompanying condensed consolidated financial statements attributable to transactions arising from its collaboration arrangements. The dollar amounts in the tables below are in thousands.


	Incyte			Lilly			Other			Total
CONTRACT ASSETS
Accounts receivable
Balance at January 1, 2023	$	—		$	—		$	1,068		$	1,068
Billings		10,779			3,497			68			14,344
Cash receipts		(9,779	)		(3,497	)		(1,142	)		(14,418	)
Adjustments		—			—			—			—
Foreign exchange		—			—			6			6
Balance at September 30, 2023	$	1,000		$	—		$	—		$	1,000

Unbilled receivables
Balance at January 1, 2023	$	1,987		$	808		$	189		$	2,984
Accrued receivables		10,152			3,541			—			13,693
Billings		(10,779	)		(3,497	)		—			(14,276	)
Adjustments		44			(7	)		—			37
Foreign exchange		—			—			(4	)		(4	)
Balance at September 30, 2023	$	1,404		$	845		$	185		$	2,434

CONTRACT LIABILITIES
Deferred revenue
Balance at January 1, 2023	$	52,059		$	16,130		$	—		$	68,189
Additions to contract consideration		—			—			—			—
Revenue recognized in the period		(12,912	)		(8,270	)		—			(21,182	)
Foreign exchange		(68	)		54			—			(14	)
Balance at September 30, 2023		39,079			7,914			—			46,993
Less: current portion		(16,882	)		(6,137	)		—			(23,019	)
Non-current balance at September 30, 2023	$	22,197		$	1,777		$	—		$	23,974

The balance of unbilled receivables predominantly represents reimbursement revenue under the Company’s collaboration arrangements earned in the period to be billed and collected in the next period, generally quarterly.

Contract Revenues and Expenses


	Three Months Ended September 30, 2023
	(In thousands)
	Third Party
	Incyte		Lilly			Other		Total
Upfront payments	$	4,371	$	789		$	—	$	5,160
Reimbursement revenue		1,547		847			—		2,394
Milestones		3,479		—			—		3,479
Other		—		—			—		—
Total collaboration revenue	$	9,397	$	1,636		$	—	$	11,033
Operating expenses:
Research and development expense	$	—	$	—		$	—	$	—
General and administrative expense		—		—			—		—
Total operating expenses from collaborations	$	—	$	—		$	—	$	—
Revenue recognized that was included in deferred revenue at the beginning of the period	$	4,371	$	789		$	—	$	5,160

	Three Months Ended September 30, 2022
	(In thousands)
	Third Party
	Incyte		Lilly			Other		Total
Upfront payments	$	4,045	$	(551	)	$	—	$	3,494
Reimbursement revenue		2,300		787			—		3,087
Milestones		—		—			—		—
Other		—		—			—		—
Total collaboration revenue	$	6,345	$	236		$	—	$	6,581
Operating expenses:
Research and development expense	$	162	$	—		$	—	$	162
General and administrative expense		—		—			—		—
Total operating expenses from collaborations	$	162	$	—		$	—	$	162
Revenue recognized that was included in deferred revenue at the beginning of the period	$	4,045	$	(551	)	$	—	$	3,494


	Nine Months Ended September 30, 2023
	(In thousands)
	Third Party
	Incyte		Lilly		Other		Total
Upfront payments	$	12,912	$	8,270	$	—	$	21,182
Reimbursement revenue		4,248		3,543		—		7,791
Milestones		5,980		—		—		5,980
Other		—		—		55		55
Total collaboration revenue	$	23,140	$	11,813	$	55	$	35,008
Operating expenses:
Research and development expense	$	24	$	—	$	—	$	24
General and administrative expense		—		—		—		—
Total operating expenses from collaborations	$	24	$	—	$	—	$	24
Revenue recognized that was included in deferred revenue at the beginning of the period	$	12,912	$	8,270	$	—	$	21,182

	Nine Months Ended September 30, 2022
	(In thousands)
	Third Party
	Incyte		Lilly		Other		Total
Upfront payments	$	12,677	$	7,634	$	222	$	20,533
Reimbursement revenue		6,514		2,823		—		9,337
Milestones		1,000		—		—		1,000
Other		—		—		50		50
Total collaboration revenue	$	20,191	$	10,457	$	272	$	30,920
Operating expenses:
Research and development expense	$	712	$	—	$	—	$	712
General and administrative expense		—		—		—		—
Total operating expenses from collaborations	$	712	$	—	$	—	$	712
Revenue recognized that was included in deferred revenue at the beginning of the period	$	12,677	$	7,634	$	222	$	20,533

Income Taxes - Additional Information (Details) - Dutch Tax Law € in Millions	9 Months Ended
	Sep. 30, 2023 EUR (€)
Income Tax Disclosure [Line Items]
Taxable income that exceeds €1.0 million, percentage	50.00%
Maximum
Income Tax Disclosure [Line Items]
Future taxable income offset limit	€ 1.0
Minimum
Income Tax Disclosure [Line Items]
Future taxable income exceeding limit	€ 1.0

Collaborations - Additional Information (Details) $ / shares in Units, € in Millions					1 Months Ended		3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jan. 18, 2021 USD ($) $ / shares shares	Aug. 31, 2018 USD ($)	Mar. 14, 2018 EUR (€)	Jan. 23, 2017 USD ($)	Jan. 31, 2022	Jan. 31, 2018 USD ($) Antibody PerformanceObligation Milestone	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Feb. 12, 2021 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development milestones achieved							$ 2,500,000
Lilly Collaborations Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Non-refundable upfront payment receivable	$ 40,000,000
Issuance of common stock, shares \| shares	706,834
Common stock stated purchase price per share \| $ / shares	$ 28.295
Proceeds from issuance of common stock, net	$ 20,000,000
Fixed consideration	43,500,000										$ 43.5
Fee incurred for extension of research term										$ 500,000
Increase in transaction price										$ 500,000
Upfront payment	40,000,000
Net fair value of shares	$ 16,500,000
Incyte Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development milestones achieved							1,000,000		$ 6,000,000
Incyte Collaboration and License Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Residual royalty percentage					4.00%
Incyte Collaboration and License Agreement \| License and Related Activities
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations, transaction price as deferred revenue				$ 152,600,000
Second ONO Research and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Non-refundable upfront payment receivable \| €			€ 0.7
Payment to compensate research services \| €			0.3
Over time payment for full time equivalent funding \| €			€ 0.2
Development milestones achieved							$ 0	$ 0
Simcere Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of bispecific antibodies under collaboration and license agreement \| Antibody						3
Non-refundable upfront payment received						$ 2,750,000
Collaborations, transaction price as revenue						$ 2,750,000
Milestone payments received		$ 1,800,000
Number of milestones achieved \| Milestone						3
Simcere Collaboration and License Agreement \| License and Performance \| Research and Development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of performance obligation \| PerformanceObligation						3

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2023	Oct. 30, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Entity Registrant Name	MERUS N.V.
Trading Symbol	MRUS
Entity Central Index Key	0001651311
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding		57,732,814
Entity File Number	001-37773
Entity Incorporation, State or Country Code	P7
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	Uppsalalaan 17
Entity Address, City or Town	Utrecht
Entity Address, Postal Zip Code	3584 CT
Entity Address, Country	NL
City Area Code	+31 85
Local Phone Number	016 2500
Document Quarterly Report	true
Document Transition Report	false
Title of 12(b) Security	Common shares, nominal value €0.09 per share
Security Exchange Name	NASDAQ

Leases (Tables)

9 Months Ended

Sep. 30, 2023

Leases [Abstract]

Summary of Components of Lease Cost

The components of lease expense for the three and nine months ended September 30, 2023 and 2022 are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(In thousands)				(In thousands)
Lease cost
Operating lease cost	$	517	$	701	$	1,743	$	1,816
Variable lease cost		53		83		137		282
Total lease cost included in operating expenses	$	570	$	784	$	1,880	$	2,098
Other information
Cash paid for amounts included in the measurement of lease liabilities included in operating cash flows	$	544	$	733	$	1,828	$	1,881

Employee Benefits - Summary of Stock-based Compensation Expense Classified in Condensed Consolidated Statements of Operations and Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total	$ 7,315	$ 6,525	$ 19,518	$ 18,521
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total	2,959	2,690	8,859	8,025
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total	$ 4,356	$ 3,835	$ 10,659	$ 10,496

- 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

Common Stock

9 Months Ended

Sep. 30, 2023

Equity [Abstract]

Common Stock

9. Common Stock

Share Issuances

In May 2021, the Company entered into an Open Market Sale Agreement (the “Sales Agreement”) with Jefferies LLC (“Jefferies”) to sell from time to time up to $125.0 million of the Company’s common stock through an “at the market” offering program under which Jefferies acts as the sales agent. Subject to the terms and conditions of the Sales Agreement, Jefferies could sell the common stock by any method deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended (the “Securities Act”).

Jefferies was entitled to compensation at a commission rate of up to 3.0% of the gross proceeds of shares sold under the Sales Agreement. In connection with the sale of the common shares on our behalf, Jefferies was deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Jefferies was deemed to be underwriting commissions or discounts. The Company agreed to provide indemnification and contribution to Jefferies with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended, or the Exchange Act.

As of December 31, 2022, the Company, pursuant to the Sales Agreement, had issued and sold an aggregate of 2,720,846 shares of its common stock resulting in gross proceeds of $59.5 million, before deducting sales agent fees of $1.7 million.

During the three months ended June 30, 2023, the Company sold 3,272,280 shares of its common stock under the Sales Agreement for gross proceeds of approximately $65.5 million and net proceeds of approximately $63.8 million, after deducting sales agent fees. Having sold approximately $124.9 million of the $125.0 million available under the Sales Agreement, on May 22, 2023, the Company delivered written notice to Jefferies, effective as of such date, to terminate the Sales Agreement. The Company was not subject to any termination penalties related to the termination of the Sales Agreement.

On August 9, 2023, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with Jefferies LLC, BofA Securities, Inc., Guggenheim Securities, LLC and William Blair & Company, L.L.C., as representatives of the several underwriters named therein (collectively, the “Underwriters”), in connection with the issuance and sale by the Company in a public offering of

6,818,182 common shares of the Company, nominal value €0.09 per share, at a public offering price of $22.00 per share, less underwriting discounts and commissions, pursuant to an effective shelf registration statement on Form S-3 and accompanying prospectus (Registration No. 333-255903), which became effective upon filing on May 7, 2021, and a prospectus supplement thereunder. Under the terms of the Underwriting Agreement, the Company also granted the Underwriters an option exercisable for 30 days to purchase up to an additional 1,022,727 common shares at the public offering price, less underwriting discounts and commissions. On August 10, 2023, the Underwriters exercised this option in full. The offering closed on August 14, 2023, and the Company received net proceeds of $162.2 million, after deducting underwriting discounts and fees.

- Definition

The entire disclosure for equity.

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-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Preparation	Basis of Presentation The Company prepared its unaudited consolidated condensed financial statements in compliance with generally accepted accounting principles in the U.S. ("U.S. GAAP"). Any reference in these notes to applicable guidance is meant to refer to 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 unaudited condensed consolidated financial statements include the accounts of Merus N.V. and its wholly owned, controlled subsidiary, Merus US, Inc. All intercompany transactions and balances of subsidiaries have been eliminated in consolidation. In the opinion of management, these financial statements reflect all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the results for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the unaudited condensed consolidated financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The three months ended September 30, 2023 and 2022 are referred to as the third quarter of 2023 and 2022, respectively. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period. The unaudited condensed consolidated financial statements presented herein do not contain the required disclosures under U.S. GAAP for annual financial statements. Therefore, these unaudited condensed consolidated financial statements should be read in conjunction with the annual audited consolidated financial statements and related notes as of and for the year ended December 31, 2022, included in the Annual Report on Form 10-K.
Going Concern	Going Concern At each reporting period, the Company evaluates whether there are conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company is required to make certain additional disclosures if it concludes substantial doubt exists and it is not alleviated by the Company’s plans or when its plans alleviate substantial doubt about the Company’s ability to continue as a going concern. The Company’s evaluation entails analyzing prospective operating budgets and forecasts for expectations of the Company’s cash needs, and comparing those needs to the current cash, cash equivalent and marketable security balances. After considering the Company’s current research and development plans and the timing expectations related to the progress of its clinical-stage programs and its plans to pursue commercialization of any antibody candidate, if approved, and after considering its existing cash, cash equivalents and marketable securities as of September 30, 2023, the Company did not identify conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year from the date these financial statements were issued. Additional details of the Company’s cash runway are described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations”.
New Accounting Pronouncements	New Accounting Pronouncements The Company considers the applicability and impact of any recent Accounting Standards Update ("ASU") issued by the Financial Accounting Standards Board ("FASB"). Based on the assessment, the ASUs were determined to be either not applicable or are expected to have minimal impact on the Company's condensed consolidated financial statements.

Leases (Additional Information) (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Liability, to be Paid, Total		$ 100,000
Former Corporate Headquarters
Lessee, Lease, Description [Line Items]
Operating lease liability	$ 0

Employee Benefits (Tables)

9 Months Ended

Sep. 30, 2023

Retirement Benefits [Abstract]

Summary of Stock-based Compensation Expense Classified in Condensed Consolidated Statements of Operations and Comprehensive Loss

Stock-based compensation expense is classified in the condensed consolidated statements of operations and comprehensive loss as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(In thousands)				(In thousands)
Research and development	$	2,959	$	2,690	$	8,859	$	8,025
General and administrative		4,356		3,835		10,659		10,496
Total	$	7,315	$	6,525	$	19,518	$	18,521

Summary of Assumptions Used to Estimate Fair Value of Options Granted

The following assumptions were used to estimate the fair value of the options granted during the nine months ended September 30, 2023.


Volatility	68.3	%
Risk-free interest rate	3.6	%
Expected holding period (in years)	6.2
Dividend yield	-

Overview - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (692,908)	$ (598,122)

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Leases

9 Months Ended

Sep. 30, 2023

Leases [Abstract]

Leases

7. Leases

The Company has noncancelable operating leases for offices and lab spaces expiring at various dates through 2032.

On December 7, 2022, the Company signed a second lease amendment terminating the lease for the former corporate headquarters as of January 1, 2023. The Company continued to make payments through mid-February 2023. The Company accounted for the second amendment as a lease modification and reduced the lease liability and right-of-use asset by approximately $0.1 million to equal to the remaining lease payments. As of March 31, 2023, the lease liability and right-of-use asset for the former corporate headquarters was $0. In July 2019, the Company entered into a lease agreement with Kadans Science Partner XIII B.V. for the Accelerator headquarters, which commenced in April 2022. During the three months ended June 30, 2023, in accordance with the terms of the lease agreement, the annual rent for the Accelerator lease increased due to increases in the consumer price index (CPI). The portion of the rent payments related to the CPI index are included within variable lease costs. There have been no changes in the Company’s lease arrangements for the three months ended September 30, 2023.

The components of lease expense for the three and nine months ended September 30, 2023 and 2022 are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(In thousands)				(In thousands)
Lease cost
Operating lease cost	$	517	$	701	$	1,743	$	1,816
Variable lease cost		53		83		137		282
Total lease cost included in operating expenses	$	570	$	784	$	1,880	$	2,098
Other information
Cash paid for amounts included in the measurement of lease liabilities included in operating cash flows	$	544	$	733	$	1,828	$	1,881

Insider Trading Arrangements	9 Months Ended
Insider Trading Arrangements	Sep. 30, 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

Employee Benefits - Summary of Assumptions Used to Estimate Fair Value of Options Granted (Details)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Volatility	68.30%
Risk-free interest rate	3.60%
Expected holding period (in years)	6 years 2 months 12 days

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 241,868	$ 147,749
Marketable securities	146,702	142,480
Accounts receivable	3,434	4,051
Prepaid expenses and other current assets	12,828	12,163
Total current assets	404,832	306,443
Marketable securities	57,259	36,457
Property and equipment, net	12,176	12,222
Operating lease right-of-use assets	11,323	12,618
Intangible assets, net	1,771	1,950
Deferred tax assets	702	2,041
Other assets	4,123	4,811
Total assets	492,186	376,542
Current liabilities:
Accounts payable	3,843	9,834
Accrued expenses and other liabilities	35,712	35,590
Income taxes payable	137	2,400
Current portion of lease obligation	1,607	1,684
Current portion of deferred revenue	23,019	29,418
Total current liabilities	64,318	78,926
Lease obligation	10,506	11,790
Deferred revenue, net of current portion	23,974	38,771
Total liabilities	98,798	129,487
Commitments and contingencies - Note 6
Stockholders’ equity:
Common shares, Euro 0.09 par value; 67,500,000 shares authorized at September 30, 2023 and December 31, 2022; 57,729,180 and 46,310,589 shares issued and outstanding as at September 30, 2023 and December 31, 2022, respectively	5,874	4,751
Additional paid-in capital	1,117,855	870,874
Accumulated other comprehensive income	(37,433)	(30,448)
Accumulated deficit	(692,908)	(598,122)
Total stockholders’ equity	393,388	247,055
Total liabilities and stockholders’ equity	$ 492,186	$ 376,542

Supplemental Balance Sheet Information (Tables)

9 Months Ended

Sep. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Schedule of Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Prepaid research and development expenses	$	4,296	$	6,372
Prepaid general and administrative expenses		5,960		2,940
Interest receivable		1,173		647
Other		1,399		2,204
Total	$	12,828	$	12,163

Summary of Accrued Expenses and Other Liabilities

Accrued expenses and other liabilities consisted of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Accrued research and development expenses	$	27,760	$	26,159
Accrued personnel costs		5,145		5,778
Accrued general and administrative expenses		2,734		3,615
Other		73		38
Total	$	35,712	$	35,590

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (94,786)	$ (49,222)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization of property and equipment	1,752	778
Amortization of intangible assets	170	195
Foreign exchange gain	(3,548)	(68,654)
Stock-based compensation expense	19,518	18,521
Amortization (accretion) of discount on investments	(3,899)	243
Deferred tax expense (benefit)	1,340	(19)
Changes in operating assets and liabilities:
Accounts receivable	602	3,031
Operating lease right-of-use assets and lease obligations	(62)	846
Prepaid expenses and other current assets	(14)	(8,987)
Accounts payable	(4,482)	(9,067)
Accrued expenses and other liabilities	(1,273)	12,514
Deferred revenue	(21,177)	(19,566)
Net cash used in operating activities	(105,859)	(119,387)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities	(204,087)	(170,692)
Proceeds from maturities of marketable securities	183,192	178,169
Purchases of property and equipment	(4,008)	(5,531)
Net cash provided by (used in) investing activities	(24,903)	1,946
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock, net	225,945	57,972
Payments of offering costs	(443)	(231)
Proceeds from stock options exercised	3,084	1,213
Net cash provided by financing activities	228,586	58,954
Foreign exchange impact on cash, cash equivalents and restricted cash	(3,648)	8,866
Net increase (decrease) in cash, cash equivalents and restricted cash	94,176	(49,621)
Cash, cash equivalents, and restricted cash, beginning of period	148,439	241,749
Cash, cash equivalents, and restricted cash, end of period	242,615	192,128
SUPPLEMENTAL DISCLOSURES:
Lease liabilities arising from obtaining right-of-use assets	0	11,493
Income taxes paid	3,103	0
Non-cash purchases of property, equipment and intangibles	0	2
CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Cash and cash equivalents	241,868	190,980
Restricted cash included in non-current other assets	747	1,148
Cash, cash equivalents, and restricted cash, end of period	$ 242,615	$ 192,128

Investments in Debt Securities (Tables)

9 Months Ended

Sep. 30, 2023

Debt Securities [Abstract]

Summary of Investments in Debt Securities in Condensed Consolidated Balance Sheet

The following tables summarize the Company’s investments in debt securities and their presentation in the condensed consolidated balance sheet:


	September 30, 2023		December 31, 2022
	(in thousands)
Money market funds	$	20,499	$	18,404
Corporate paper and notes		134,511		126,102
U.S. government agency securities		52,669		34,364
U.S. treasuries		21,482		18,471
Total	$	229,161	$	197,341

Fair value of debt securities	$	228,314	$	196,345


	September 30, 2023		December 31, 2022
	(in thousands)
Cash equivalents	$	25,200	$	18,404
Current marketable securities		146,702		142,480
Non-current marketable securities		57,259		36,457
Total	$	229,161	$	197,341

Income Taxes (Tables)

9 Months Ended

Sep. 30, 2023

Income Tax Disclosure [Abstract]

Summary of Components of Expense for (Benefit) from Income Taxes

The components of the income tax expense (benefit) from continuing operations are as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2023			2022			2023		2022
	(In thousands)						(In thousands)
U.S. federal	$	(871	)	$	370		$	580	$	420
U.S. state		(366	)		152			235		171
Total current income tax benefit	$	(1,237	)	$	522		$	815	$	591

U.S. federal	$	1,665		$	(137	)	$	947	$	(13	)
U.S. state		690			(58	)		393		(6	)
Total deferred income tax expense (benefit)	$	2,355		$	(195	)	$	1,340	$	(19	)

Total income tax expense (benefit)	$	1,118		$	327		$	2,155	$	572

Supplemental Balance Sheet Information - Summary of Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 27,760	$ 26,159
Accrued personnel costs	5,145	5,778
Accrued general and administrative expenses	2,734	3,615
Other	73	38
Total	$ 35,712	$ 35,590

Employee Benefits

9 Months Ended

Sep. 30, 2023

Retirement Benefits [Abstract]

Employee Benefits

10. Employee Benefits

Stock-Based Compensation

Stock-based compensation expense is classified in the condensed consolidated statements of operations and comprehensive loss as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
	(In thousands)				(In thousands)
Research and development	$	2,959	$	2,690	$	8,859	$	8,025
General and administrative		4,356		3,835		10,659		10,496
Total	$	7,315	$	6,525	$	19,518	$	18,521

The weighted-average grant date fair value of options, estimated as of the grant date using the Black Scholes option pricing model was $11.67 per option for the 2,625,427 options granted during the nine months ended September 30, 2023. The following assumptions were used to estimate the fair value of the options granted during the nine months ended September 30, 2023.


Volatility	68.3	%
Risk-free interest rate	3.6	%
Expected holding period (in years)	6.2
Dividend yield	-

Executive Settlement

In April 2020, Mark Throsby, Ph.D. resigned as the Executive Vice President and Chief Scientific Officer of the Company effective July 31, 2020. In connection with his departure, Mr. Throsby entered into a Settlement Agreement with the Company, pursuant to which Mr. Throsby received a severance payment equal to 8 months of his annual salary and amortized bonus aggregating approximately $0.3 million. Further, subject to Mr. Throsby’s continued compliance with the terms and conditions of the Settlement Agreement, Mr. Throsby’s unvested equity awards continued to vest until October 31, 2020 as if Mr. Throsby had continued in full time service with the Company through such date. The post-termination exercise period of Mr. Throsby's options was extended to March 31, 2021. The Company incrementally recognized $0.1 million in respect of the severance payment and a net reversal of $0.4 million of stock-based compensation expense in respect of share-based payments in research and development expense in the consolidated statement of operations in the prior year.

In March 2021, the Company and Mr. Throsby amended the Settlement Agreement and a Consulting Agreement, extending the post-termination expiration period of his outstanding options to extend to October 31, 2021, three months following his performance of certain consulting services through July 31, 2021. As a result, additional compensation cost of $0.2 million was recognized for the quarter ended March 31, 2021. In July 2021, the Company and Mr. Throsby entered into the 2nd Amendment to the Consulting Agreement, extending Mr. Throsby’s consulting services period to February 28, 2022, extending the post-termination period of his outstanding options to May 2022. As the modification occurred in Mr. Throsby’s post-employment period, the options cease to be within the scope of ASC 718 and are recharacterized as an issuance of a standalone derivative instrument. The Company recognized a $0.4 million net gain associated with the derivative instrument included as other income in the statement of operations for the three months ended March 31, 2022. The Company did not recognize any further gains or expenses during the three months ended September 30, 2023 and the Company does not expect to incur any further expenses as Mr. Throsby's option to exercise expired in May 2022.

Investments in Debt Securities - Summary of Investments in Debt Securities in Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule Of Held To Maturity Securities [Line Items]
Total	$ 229,161	$ 197,341
Fair value of debt securities	228,314	196,345
Cash equivalents [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	25,200	18,404
Current marketable securities [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	146,702	142,480
Non-current marketable securities [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	57,259	36,457
Money market funds [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	20,499	18,404
Corporate paper and notes [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	134,511	126,102
U.S. government agency securities [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	52,669	34,364
U.S. treasuries [member]
Schedule Of Held To Maturity Securities [Line Items]
Total	$ 21,482	$ 18,471

Supplemental Balance Sheet Information - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid research and development expenses	$ 4,296	$ 6,372
Prepaid general and administrative expenses	5,960	2,940
Interest receivable	1,173	647
Other	1,399	2,204
Total	$ 12,828	$ 12,163

Collaborations - Summary of Company's Collaboration Arrangements Earned in Period to Be Billed and Collected in Next Period (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating expenses:
Research and development	$ 36,810	$ 42,307	$ 99,973	$ 100,378
General and administrative	12,591	12,469	44,040	36,917
Total operating expenses	49,401	54,776	144,013	137,295
Incyte
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	4,371	4,045	12,912	12,677
Reimbursement revenue	1,547	2,300	4,248	6,514
Milestones	3,479	0	5,980	1,000
Other	0	0	0	0
Total collaboration revenue	9,397	6,345	23,140	20,191
Operating expenses:
Research and development	0	162	24	712
General and administrative	0	0	0	0
Total operating expenses	0	162	24	712
Revenue recognized in the period	4,371	4,045	12,912	12,677
Lilly
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	789	(551)	8,270	7,634
Reimbursement revenue	847	787	3,543	2,823
Milestones	0	0	0	0
Other	0	0	0	0
Total collaboration revenue	1,636	236	11,813	10,457
Operating expenses:
Research and development	0	0	0	0
General and administrative	0	0	0	0
Total operating expenses	0	0	0	0
Revenue recognized in the period	789	(551)	8,270	7,634
Other
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	0	0	0	222
Reimbursement revenue	0	0	0	0
Milestones	0	0	0	0
Other	0	0	0	50
Total collaboration revenue	0	0	0	272
Operating expenses:
Research and development	0	0	0	0
General and administrative	0	0	0	0
Total operating expenses	0	0	0	0
Revenue recognized in the period	0	0	0	222
Collaboration Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	5,160	3,494	21,182	20,533
Reimbursement revenue	2,394	3,087	7,791	9,337
Milestones	3,479	0	5,980	1,000
Other	0	0	55	50
Total collaboration revenue	11,033	6,581	35,008	30,920
Operating expenses:
Research and development	0	162	24	712
General and administrative	0	0	0	0
Total operating expenses	0	162	24	712
Revenue recognized in the period	$ 5,160	$ 3,494	$ 21,182	$ 20,533

Collaborations (Tables)

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Company's Accompanying Condensed Consolidated Financial Statements Attributable to Transactions Arising From Collaboration Arrangements


	Incyte			Lilly			Other			Total
CONTRACT ASSETS
Accounts receivable
Balance at January 1, 2023	$	—		$	—		$	1,068		$	1,068
Billings		10,779			3,497			68			14,344
Cash receipts		(9,779	)		(3,497	)		(1,142	)		(14,418	)
Adjustments		—			—			—			—
Foreign exchange		—			—			6			6
Balance at September 30, 2023	$	1,000		$	—		$	—		$	1,000

Unbilled receivables
Balance at January 1, 2023	$	1,987		$	808		$	189		$	2,984
Accrued receivables		10,152			3,541			—			13,693
Billings		(10,779	)		(3,497	)		—			(14,276	)
Adjustments		44			(7	)		—			37
Foreign exchange		—			—			(4	)		(4	)
Balance at September 30, 2023	$	1,404		$	845		$	185		$	2,434

CONTRACT LIABILITIES
Deferred revenue
Balance at January 1, 2023	$	52,059		$	16,130		$	—		$	68,189
Additions to contract consideration		—			—			—			—
Revenue recognized in the period		(12,912	)		(8,270	)		—			(21,182	)
Foreign exchange		(68	)		54			—			(14	)
Balance at September 30, 2023		39,079			7,914			—			46,993
Less: current portion		(16,882	)		(6,137	)		—			(23,019	)
Non-current balance at September 30, 2023	$	22,197		$	1,777		$	—		$	23,974

Summary of Company's Collaboration Arrangements Earned in Period to Be Billed and Collected in Next Period

Contract Revenues and Expenses


	Three Months Ended September 30, 2023
	(In thousands)
	Third Party
	Incyte		Lilly			Other		Total
Upfront payments	$	4,371	$	789		$	—	$	5,160
Reimbursement revenue		1,547		847			—		2,394
Milestones		3,479		—			—		3,479
Other		—		—			—		—
Total collaboration revenue	$	9,397	$	1,636		$	—	$	11,033
Operating expenses:
Research and development expense	$	—	$	—		$	—	$	—
General and administrative expense		—		—			—		—
Total operating expenses from collaborations	$	—	$	—		$	—	$	—
Revenue recognized that was included in deferred revenue at the beginning of the period	$	4,371	$	789		$	—	$	5,160

	Three Months Ended September 30, 2022
	(In thousands)
	Third Party
	Incyte		Lilly			Other		Total
Upfront payments	$	4,045	$	(551	)	$	—	$	3,494
Reimbursement revenue		2,300		787			—		3,087
Milestones		—		—			—		—
Other		—		—			—		—
Total collaboration revenue	$	6,345	$	236		$	—	$	6,581
Operating expenses:
Research and development expense	$	162	$	—		$	—	$	162
General and administrative expense		—		—			—		—
Total operating expenses from collaborations	$	162	$	—		$	—	$	162
Revenue recognized that was included in deferred revenue at the beginning of the period	$	4,045	$	(551	)	$	—	$	3,494


	Nine Months Ended September 30, 2023
	(In thousands)
	Third Party
	Incyte		Lilly		Other		Total
Upfront payments	$	12,912	$	8,270	$	—	$	21,182
Reimbursement revenue		4,248		3,543		—		7,791
Milestones		5,980		—		—		5,980
Other		—		—		55		55
Total collaboration revenue	$	23,140	$	11,813	$	55	$	35,008
Operating expenses:
Research and development expense	$	24	$	—	$	—	$	24
General and administrative expense		—		—		—		—
Total operating expenses from collaborations	$	24	$	—	$	—	$	24
Revenue recognized that was included in deferred revenue at the beginning of the period	$	12,912	$	8,270	$	—	$	21,182

	Nine Months Ended September 30, 2022
	(In thousands)
	Third Party
	Incyte		Lilly		Other		Total
Upfront payments	$	12,677	$	7,634	$	222	$	20,533
Reimbursement revenue		6,514		2,823		—		9,337
Milestones		1,000		—		—		1,000
Other		—		—		50		50
Total collaboration revenue	$	20,191	$	10,457	$	272	$	30,920
Operating expenses:
Research and development expense	$	712	$	—	$	—	$	712
General and administrative expense		—		—		—		—
Total operating expenses from collaborations	$	712	$	—	$	—	$	712
Revenue recognized that was included in deferred revenue at the beginning of the period	$	12,677	$	7,634	$	222	$	20,533

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total revenue	$ 11,033	$ 6,581	$ 35,008	$ 30,920
Operating expenses:
Research and development	36,810	42,307	99,973	100,378
General and administrative	12,591	12,469	44,040	36,917
Total operating expenses	49,401	54,776	144,013	137,295
Operating loss	(38,368)	(48,195)	(109,005)	(106,375)
Other income, net:
Interest income, net	4,522	866	9,312	1,288
Foreign exchange gains (loss)	11,952	23,041	7,062	55,378
Other gains, net	0	0	0	1,059
Total other income (loss), net	16,474	23,907	16,374	57,725
Net loss before income taxes	(21,894)	(24,288)	(92,631)	(48,650)
Income tax expense	1,118	327	2,155	572
Net loss	(23,012)	(24,615)	(94,786)	(49,222)
Other comprehensive loss:
Currency translation adjustment	(10,722)	(19,475)	(6,985)	(45,444)
Comprehensive loss	$ (33,734)	$ (44,090)	$ (101,771)	$ (94,666)
Net loss per share attributable to common stockholders:
Basic	$ (0.43)	$ (0.53)	$ (1.91)	$ (1.11)
Diluted	$ (0.43)	$ (0.53)	$ (1.91)	$ (1.11)
Weighted-average common shares outstanding:
Basic	53,869,762	46,056,719	49,532,722	44,451,997
Diluted	53,869,762	46,056,719	49,532,722	44,451,997
Collaboration Revenue [Member]
Total revenue from contracts with customers	$ 11,033	$ 6,581	$ 35,008	$ 30,920

Commitments and Contingencies

9 Months Ended

Sep. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

6. Commitments and Contingencies

Litigation

From time to time, the Company may be involved in various claims and legal proceedings relating to or arising out of the Company’s operations. The Company is not currently a party to any material legal proceedings.

On August 19, 2022, Kymab Limited, a subsidiary of Sanofi, filed a notice of opposition against the Company's EP3456190 patent (the "'190 patent"), entitled "Antibody Producing Transgenic Murine Animal," in the European Opposition Division of the European Patent Office (the "EPO"). The notice asserted, as applicable, the '190 patent is contrary to the provision of Article 123(2) EPC, Article 75(1) EPC and Article 100(c) EPC, and alleges the '190 patent lacks novelty and/or is obvious contrary to the provisions of Articles 54 and/or 56 EPC, and Article 100(a) EPC, and that the specification of the '190 patent does not provide sufficient disclosure of the subject matter of the inventions contravening Article 83 EPC and Article 100(b). On January 17, 2023, the Company timely filed a response before the European Opposition Division of the EPO contesting each of these assertions, with further oral proceedings scheduled to follow on January 18, 2024. On June 2, 2023, the European Opposition Division issued a non-binding preliminary decision finding the claims as granted in the '190 patent mostly fulfills the requirements of Art. 123(2) and Art. 76(1), that the opponent has failed to provide serious doubts substantiated by verifiable facts in support of an allegation that the '190 patent claims lack sufficiency of disclosure under Art. 100(b) and Art. 83, and that further issues of claim construction, novelty and inventive step are to be discussed during the oral proceedings.

Collaborations - Summary of Company's Accompanying Consolidated Financial Statements Attributable to Transactions Arising From Collaboration Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Incyte
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized in the period	$ 4,371	$ 4,045	$ 12,912	$ 12,677
Incyte \| Accounts Receivable
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Billings			10,779
Cash receipts			(9,779)
Balance at September 30, 2023	1,000		1,000
Incyte \| Unbilled Receivables
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			1,987
Accrued receivables			10,152
Billings			(10,779)
Adjustments			44
Balance at September 30, 2023	1,404		1,404
Incyte \| Deferred Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023	39,079		39,079		$ 52,059
Foreign exchange			(68)
Revenue recognized in the period			(12,912)
Balance at September 30, 2023	39,079		39,079		52,059
Less: current portion	(16,882)		(16,882)
Non-current balance at September 30, 2023	22,197		22,197
Lilly
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized in the period	789	(551)	8,270	7,634
Lilly \| Accounts Receivable
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Billings			3,497
Cash receipts			(3,497)
Lilly \| Unbilled Receivables
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			808
Accrued receivables			3,541
Billings			(3,497)
Adjustments			(7)
Balance at September 30, 2023	845		845
Lilly \| Deferred Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023	7,914		7,914		16,130
Foreign exchange			54
Revenue recognized in the period			(8,270)
Balance at September 30, 2023	7,914		7,914		16,130
Less: current portion	(6,137)		(6,137)
Non-current balance at September 30, 2023	1,777		1,777
Other
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized in the period	0	0	0	222
Other \| Accounts Receivable
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			1,068
Billings			68
Cash receipts			(1,142)
Foreign exchange			6
Other \| Unbilled Receivables
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			189
Foreign exchange			(4)
Balance at September 30, 2023	185		185
Collaboration Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized in the period	5,160	$ 3,494	21,182	$ 20,533
Collaboration Agreement \| Accounts Receivable
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			1,068
Billings			14,344
Cash receipts			(14,418)
Foreign exchange			6
Balance at September 30, 2023	1,000		1,000
Collaboration Agreement \| Unbilled Receivables
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023			2,984
Accrued receivables			13,693
Billings			(14,276)
Adjustments			37
Foreign exchange			(4)
Balance at September 30, 2023	2,434		2,434
Collaboration Agreement \| Deferred Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at January 1, 2023	46,993		46,993		68,189
Foreign exchange			(14)
Revenue recognized in the period			(21,182)
Balance at September 30, 2023	46,993		46,993		$ 68,189
Less: current portion	(23,019)		(23,019)
Non-current balance at September 30, 2023	$ 23,974		$ 23,974