0001847903-21-000025 | 10-Q | XBRL Viewer | Centessa Pharmaceuticals PLC

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Cover - shares	9 Months Ended
Cover - shares	Sep. 30, 2021	Nov. 15, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Entity Transition Report	false
Entity File Number	001-04321
Entity Registrant Name	CENTESSA PHARMACEUTICALS PLC
Entity Incorporation, State or Country Code	X0
Entity Address, Address Line One	3rd Floor
Entity Address, Address Line Two	1 Ashley Road
Entity Address, Address Line Three	Altrincham
Entity Address, City or Town	Cheshire
Entity Address, Postal Zip Code	WA14 2DT
Entity Address, Country	GB
Country Region	+44
City Area Code	7391
Local Phone Number	789784
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		89,900,916
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001847903
Current Fiscal Year End Date	--12-31
Ordinary Shares
Document Information [Line Items]
Title of 12(b) Security	Ordinary shares, nominal value £0.002 per share
Trading Symbol	CNTA
Security Exchange Name	NASDAQ
American Depositary Shares
Document Information [Line Items]
Title of 12(b) Security	American Depositary Shares, each representing one ordinary share, nominal value £0.002 per share
Trading Symbol	CNTA
Security Exchange Name	NASDAQ

Consolidated and Combined Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 578,815	$ 7,227
Tax incentive receivable	18,611	2,633
Prepaid expenses and other current assets	14,219	1,305
Total current assets	611,645	11,165
Property and equipment, net	114	0
Tax incentive receivable	0	552
Debt issuance costs	448	0
Total assets	612,207	11,717
Current liabilities:
Accounts payable	18,456	1,032
Accrued expenses and other current liabilities	10,688	1,047
Convertible term notes	0	5,339
Term loans	0	288
Derivative liability	0	913
Total current liabilities	29,144	8,619
Contingent value rights	33,930	0
Total liabilities	63,074	8,619
Commitments and contingencies (Note 7)
Convertible preferred shares (£0.0001 nominal value): No shares authorized issued and outstanding at September 30, 2021; 6,549,205 shares issued and outstanding at December 31, 2020	0	25,521
Combined deficit and shareholders’ equity:
Members' Equity		(22,423)
Series A convertible preferred shares: £0.002 nominal value: 22,840,902 shares authorized. No shares issued and outstanding	0
Ordinary shares: £0.002 nominal value: 89,900,425 shares authorized, issued and outstanding at September 30, 2021; No shares authorized, issued and outstanding at December 31, 2020	252
Additional paid-in capital	871,022
Accumulated other comprehensive income (loss)	2,738
Accumulated deficit	(324,879)
Total shareholders' equity	549,133
Total combined deficit and shareholders' equity		3,098
Total liabilities, convertible preferred shares, combined deficit and shareholders' equity	$ 612,207	$ 11,717

Consolidated and Combined Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		8 Months Ended	9 Months Ended
	Jan. 29, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expenses:
Research and development	$ 600	$ 25,850	$ 1,923	$ 54,126	$ 6,604
General and administrative	121	12,464	193	29,900	831
Change in fair value of contingent value rights	0	0	0	11,312	0
Acquired in-process research and development	0	0	0	220,454	0
Loss from operations	(721)	(38,314)	(2,116)	(315,792)	(7,435)
Interest income (expense), net	(9)	65	(22)	100	(56)
Amortization of debt discount	(37)	0	(78)	0	(220)
Other income (expense), net	0	(1,906)	6	(4,605)	(5)
Gain on extinguishment of debt	0	0	72	0	339
Income tax charge	0	0	0	0	0
Net loss	(767)	(40,155)	(2,138)	(320,297)	(7,377)
Other comprehensive loss:
Foreign currency translation adjustment	45	(487)	372	2,828	(359)
Total comprehensive loss	$ (722)	$ (40,642)	$ (1,766)	$ (317,469)	$ (7,736)
Net loss per ordinary share - basic (in dollars per share)		$ (0.45)		$ (4.60)
Net loss per ordinary share - diluted (in dollars per share)		$ (0.45)		$ (4.60)
Weighted average ordinary shares outstanding - basic (in shares)		89,899,454		69,597,648
Weighted average ordinary shares outstanding - diluted (in shares)		89,899,454		69,597,648

Consolidated and Combined Statement of Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Centessa Pharmaceuticals plc	IPO	Over-Allotment Option	Series A Preferred Series A Preferred	Series A Preferred Series A Preferred Centessa Pharmaceuticals plc	Ordinary Shares	Ordinary Shares Centessa Pharmaceuticals plc	Ordinary Shares IPO	Ordinary Shares Over-Allotment Option	Additional paid-in capital	Additional paid-in capital Centessa Pharmaceuticals plc	Additional paid-in capital IPO	Additional paid-in capital Over-Allotment Option	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Centessa Pharmaceuticals plc	Accumulated Deficit	Accumulated Deficit Centessa Pharmaceuticals plc
Beginning balance (in shares) at Dec. 31, 2020						0		7,500,000
Beginning balance at Dec. 31, 2020		$ (3,214)				$ 0		$ 21				$ 0				$ (86)		$ (3,149)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries	$ 0
Foreign currency translation adjustment	45	(4)														(4)
Net loss	(767)	(1,433)																(1,433)
Ending balance (in shares) at Jan. 29, 2021					0	0	7,500,000	7,500,000
Ending balance at Jan. 29, 2021	(4,651)	(4,651)			$ 0	$ 0	$ 21	$ 21			$ 0	0			$ (90)	(90)	$ (4,582)	(4,582)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Sale of shares, net of issuance costs (in shares)					22,272,721
Sale of shares, net of issuance costs	241,597				$ 241,597
Issuance of Series A convertible preferred shares upon conversion of debt (in shares)					568,181
Issuance of Series A convertible preferred shares upon conversion of debt	6,250				$ 6,250
Acquisition of Centessa Subsidiaries (in shares)							44,758,079
Acquisition of Centessa Subsidiaries	262,698						$ 123				262,575
Forgiveness of convertible term loan	6,199										6,199
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries (in shares)							(4,450,000)
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries	(12)						$ (12)
Stock option exercises (in shares)							50,000
Stock option exercises	292										292
Vesting of ordinary shares (in shares)							225,438
Vesting of ordinary shares	0						$ 1				(1)
Share-based compensation expense	2,731										2,731
Foreign currency translation adjustment	2,221														2,221
Net loss	(238,691)																(238,691)
Ending balance (in shares) at Mar. 31, 2021					22,840,902		48,083,517
Ending balance at Mar. 31, 2021	278,634				$ 247,847		$ 133				271,796				2,131		(243,273)
Beginning balance (in shares) at Jan. 29, 2021					0	0	7,500,000	7,500,000
Beginning balance at Jan. 29, 2021	(4,651)	$ (4,651)			$ 0	$ 0	$ 21	$ 21			0	$ 0			(90)	$ (90)	(4,582)	$ (4,582)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Forgiveness of convertible term loan	$ 6,200
Stock option exercises (in shares)	50,000
Foreign currency translation adjustment	$ 2,828
Net loss	(320,297)
Ending balance (in shares) at Sep. 30, 2021					0		89,900,425
Ending balance at Sep. 30, 2021	549,133				$ 0		$ 252				871,022				2,738		(324,879)
Beginning balance (in shares) at Mar. 31, 2021					22,840,902		48,083,517
Beginning balance at Mar. 31, 2021	278,634				$ 247,847		$ 133				271,796				2,131		(243,273)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Series A convertible preferred shares into ordinary shares (in shares)					(22,840,902)		22,840,902
Conversion of Series A convertible preferred shares into ordinary shares	0				$ (247,847)		$ 65				247,782
Sale of shares, net of issuance costs (in shares)									16,500,000	2,475,000
Sale of shares, net of issuance costs			$ 298,077	$ 46,059					$ 47	$ 7			$ 298,030	$ 46,052
Share-based compensation expense	3,229										3,229
Foreign currency translation adjustment	1,094														1,094
Net loss	(41,451)																(41,451)
Ending balance (in shares) at Jun. 30, 2021					0		89,899,419
Ending balance at Jun. 30, 2021	585,642				$ 0		$ 252				866,889				3,225		(284,724)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of ordinary shares (in shares)							1,006
Share-based compensation expense	4,133										4,133
Foreign currency translation adjustment	(487)														(487)
Net loss	(40,155)																(40,155)
Ending balance (in shares) at Sep. 30, 2021					0		89,900,425
Ending balance at Sep. 30, 2021	$ 549,133				$ 0		$ 252				$ 871,022				$ 2,738		$ (324,879)

Combined Statement of Convertible Preferred Shares and Combined Deficit - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended			8 Months Ended	9 Months Ended
	Jan. 29, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Increase (Decrease) in Temporary Equity [Roll Forward]
Temporary equity, beginning balance (in shares)	6,549,205
Temporary equity, beginning balance	$ 25,521
Temporary equity, ending balance (in shares)						0
Temporary equity, ending balance						$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Combined deficit, beginning balance	(22,423)	$ (23,145)	$ (17,612)	$ (15,512)	$ (11,857)	(23,145)	$ (11,857)
Share-based compensation expense		2,731	29	153	63
Foreign currency translation adjustment	45	2,221	372	(25)	(707)	2,828	(359)
Net loss	(767)	$ (238,691)	(2,138)	(2,228)	(3,011)	$ (320,297)	(7,377)
Combined deficit, ending balance	$ (23,145)		$ (19,349)	$ (17,612)	$ (15,512)		$ (19,349)
Preferred Stock \| Series A Preferred
Increase (Decrease) in Temporary Equity [Roll Forward]
Temporary equity, beginning balance (in shares)	4,337,282	4,337,282	4,337,282	4,337,282	4,337,282	4,337,282	4,337,282
Temporary equity, beginning balance	$ 13,329	$ 13,329	$ 13,329	$ 13,329	$ 13,329	$ 13,329	$ 13,329
Temporary equity, ending balance (in shares)	4,337,282		4,337,282	4,337,282	4,337,282		4,337,282
Temporary equity, ending balance	$ 13,329		$ 13,329	$ 13,329	$ 13,329		$ 13,329
Preferred Stock \| Series B Preferred
Increase (Decrease) in Temporary Equity [Roll Forward]
Temporary equity, beginning balance (in shares)	1,111,923	1,111,923	1,111,923	1,111,923	1,111,923	1,111,923	1,111,923
Temporary equity, beginning balance	$ 10,840	$ 10,840	$ 10,840	$ 10,840	$ 10,840	$ 10,840	$ 10,840
Temporary equity, ending balance (in shares)	1,111,923		1,111,923	1,111,923	1,111,923		1,111,923
Temporary equity, ending balance	$ 10,840		$ 10,840	$ 10,840	$ 10,840		$ 10,840
Preferred Stock \| Series Seed Preferred
Increase (Decrease) in Temporary Equity [Roll Forward]
Temporary equity, beginning balance (in shares)	1,100,000	1,100,000	1,100,000	1,100,000	1,100,000	1,100,000	1,100,000
Temporary equity, beginning balance	$ 1,352	$ 1,352	$ 1,352	$ 1,352	$ 1,352	$ 1,352	$ 1,352
Temporary equity, ending balance (in shares)	1,100,000		1,100,000	1,100,000	1,100,000		1,100,000
Temporary equity, ending balance	$ 1,352		$ 1,352	$ 1,352	$ 1,352		$ 1,352

Consolidated and Combined Statements of Cash Flows - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended			8 Months Ended		9 Months Ended
	Jan. 29, 2021	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (767)	$ (238,691)	$ (40,155)	$ (2,138)	$ (3,011)	$ (320,297)	$ (320,297)		$ (7,377)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired in-process research and development	0		0	0		220,454	220,454		0
Share-based compensation expense	0					10,093			245
Depreciation and amortization	0					22			0
Non-cash interest	9					0			32
Amortization of unpaid D&O insurance premiums	0					2,972			0
Amortization of debt discount	(37)		0	(78)		0	0		(220)
Gain on extinguishment of debt	0		0	(72)		0	0		(339)
Change in fair value of contingent consideration	0		0	0		11,312	11,312		0
Changes in operating assets and liabilities:
Tax incentive receivable	74					(10,253)			(948)
Prepaid expenses and other assets	681					(6,149)			891
Accounts payable	(358)					5,529			(42)
Accrued expenses and other liabilities	(589)					7,635			(31)
Net cash used in operating activities	(987)					(78,682)			(7,349)
Cash flows from investing activities:
Cash acquired upon acquisition of Centessa Subsidiaries	0					68,038			0
Cash paid to acquire in-process research and development	0					(4,596)			0
Purchase of property and equipment	0					(122)			0
Net cash provided by investing activities	0					63,320			0
Cash flows from financing activities:
Proceeds from the sale of Series A convertible preferred shares, net of issuance costs	0					241,597			0
Proceeds from the sale of ordinary shares in connection with initial public offering, net of issuance costs paid in cash	0					344,136			0
Repurchase of ordinary shares	0					(12)			0
Repayment of related party loan	0					(295)			0
Proceeds from option exercises	0					292			0
Proceeds from related party loan	0					0			77
Net cash provided by financing activities	0					585,718			77
Effect of exchange rate on cash and cash equivalents	18					3,493			(430)
Net increase (decrease) in cash and cash equivalents	(969)					573,849			(7,702)
Cash and cash equivalents at beginning of period	7,227	6,258			$ 16,570	4,966	6,258	$ 7,227	16,570
Cash and cash equivalents at end of period	6,258		$ 578,815	$ 8,868		578,815	$ 578,815	$ 578,815	8,868
Supplemental disclosure of non-cash investing and financing activities:
Issuance of ordinary shares upon acquisition of Centessa Subsidiaries	0					262,698			0
Issuance of contingent value rights upon acquisition of Centessa Subsidiaries						22,618
Issuance of Series A convertible preferred shares upon conversion of debt	0					6,250			0
Forgiveness of convertible term loan	0					6,199			0
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries	0	$ (12)				(12)			0
Unpaid debt issuance costs at September 30, 2021	$ 0					$ 448			$ 0

Consolidated and Combined Balance Sheets (Parenthetical) - £ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Temporary equity, nominal value (in pound sterling per share)	£ 0.0001	£ 0.0001
Temporary equity, shares authorized (in shares)	0
Temporary equity, shares issued (in shares)	0	6,549,205
Temporary equity, shares outstanding (in shares)	0	6,549,205
Preferred stock, nominal value (in pound sterling per share)	£ 0.002
Preferred stock, shares authorized (in shares)	22,840,902
Preferred stock, shares issued (in shares)	0
Preferred stock, shares outstanding (in shares)	0
Common stock, nominal value (in pound sterling per share)	£ 0.002	£ 0.002
Common stock, shares authorized (in shares)	89,900,425	0
Common stock, shares issued (in shares)	89,900,425	0
Common Stock, shares outstanding (in shares)	89,900,425	0

Consolidated and Combined Statement of Shareholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended
	Mar. 31, 2021	Jun. 30, 2021
Statement of Stockholders' Equity [Abstract]
Debt issuance costs	$ 3,403	$ 8,800

Organization and Description of Business	9 Months Ended
Organization and Description of Business	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business Centessa Pharmaceuticals plc (“Centessa” or “the Company”) is a pharmaceutical company conceived to bring impactful new medicines to patients by combining the strengths of an asset-centric model with the benefits of scale and diversification typical of larger R&D organizations. Centessa was incorporated on October 26, 2020 as a limited liability company under the laws of England and Wales. In connection with the IPO, we re-registered Centessa Pharmaceuticals Limited as an English public limited company and renamed it as Centessa Pharmaceuticals plc. In January 2021, the management and equity holders of ApcinteX Limited, Capella Biosciences Limited, Inexia Limited, Janpix Limited, LockBody Therapeutics Ltd, Morphogen-IX Limited, Orexia Limited, Palladio Biosciences, Inc., PearlRiver Bio GmbH, Pega-One S.A.S., and Z Factor Limited (together, the “Centessa Subsidiaries”), contributed the Centessa Subsidiaries to Centessa, in a share for share exchange, after which these companies became wholly-owned subsidiaries of Centessa. As the Company had no significant operations prior to the contribution of the Centessa Subsidiaries, and the registrant was required to present two years of historical financial statements in its prospectus filed with the SEC on June 2, 2021, the Company’s management (“Management”) sought to identify a predecessor, for which it could include audited historical financial statements, to satisfy the filing requirement. As such, Management sought to identify the predecessor from the population of portfolio companies, which would represent a sizable portion of the historical results of the entities later contributed to Centessa. Entities affiliated with Medicxi manage multiple investment funds, including – Medicxi Ventures I LP, Medicxi Growth I LP, and Medicxi Secondary I LP. In addition, entities affiliated with Medicxi act as sub advisors to Index Ventures Life VI (Jersey) Limited which advises the managing general partner of Index Ventures Life VI (Jersey), L.P. (all funds collectively are referred to as the “Funds”). Management determined the companies owned by Index Ventures Life VI (Jersey), LP individually represent some of the earliest investments by the Funds. These companies (together, the “Centessa Predecessor Group” or the “Group”) are: •Z Factor Limited (“Z Factor”) •LockBody Therapeutics Ltd (“LockBody”) •Morphogen-IX Limited (“Morphogen-IX”) As the above entities that comprise the Centessa Predecessor Group were historically under the common control of Index Ventures Life VI (Jersey), LP, the financial statements of the Group are being presented on a combined basis and are denoted as “Predecessor” within these unaudited interim financial statements. Subsequent to the contribution of the Centessa Subsidiaries to Centessa, the financial activities of Centessa and all Centessa Subsidiaries are being presented on a consolidated basis and are denoted as “Successor” within these unaudited interim financial statements. Initial Public Offering In June 2021, the Company completed an initial public offering (“IPO”) of its ordinary shares through the sale and issuance of 16,500,000 American Depository Shares (“ADSs”), at an initial price of $20.00 per ADS. Each ADS represents one ordinary share with a nominal value of £0.002 per ordinary share. Following the close of the IPO, the underwriters fully exercised their option to purchase an additional 2,475,000 ADSs at the initial public offering price of $20.00 per ADS. The Company received aggregate net proceeds of $344.1 million in connection with the IPO and subsequent exercise of the underwriter’s options after deducting underwriting discounts, commissions and other offering expenses paid or to be paid. Risks and Liquidity The Group and the Company are subject to risks common to other life science companies in various stages of development including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on key personnel, market acceptance of products, product liability, protection of proprietary technology, ability to raise additional financing and compliance with government regulations, in the markets in which the Company is seeking approvals, including U.S. Food and Drug Administration (“FDA”) regulations. If the Company does not successfully advance its programs, including the Centessa Subsidiaries’ programs, into and through human clinical trials and/or enter into collaborations for its programs and commercialize any of its product candidates, it may be unable to produce product revenue or achieve profitability. For more information on risks, please see Part II Item 1A of this Form 10-Q – Risk Factors. The Group and the Company have incurred losses and negative cash flows from operations since inception and the Company had an accumulated deficit of $(324.9) million as of September 30, 2021. The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of the product candidates currently in development by the Centessa Subsidiaries. Substantial additional capital will be needed by the Company to fund its operations (including those of the Centessa Subsidiaries) and to develop its product candidates. In October 2021, the Company entered into a Note Purchase Agreement with Oberland Capital Management LLC (Oberland Capital). Under the terms of the agreement, Oberland Capital will purchase up to $300.0 million of 6-year, interest-only (initial interest rate is 8.0% per annum), senior secured notes (the Notes) from the Company including $75.0 million, funded on October 4, 2021, $125.0 million available within 24 months at the Company’s option, and $100.0 million available to fund Mergers and Acquisitions ("M&A"), in-licensing, or other strategic transactions, at the option of the Company and Oberland Capital (See - Note 12 – "Subsequent Events"). The Company expects its existing cash and cash equivalents will be sufficient to fund its expected operating expenses and capital expenditure requirements for at least the next 12 months from the date of issuance of these unaudited consolidated financial statements. Based on the current non-risk-adjusted operating plan, the Company expects the cash and cash equivalents as of September 30, 2021 of $578.8 million, plus the net proceeds of the First Purchase Note of $74.6 million received on October 4, 2021, supplemented by the additional funds available under the Oberland Capital Note Purchase Agreement, if drawn, to fund its operations into mid-2024. Global Pandemic – COVID-19 On March 10, 2020, the World Health Organization characterized the novel COVID-19 virus as a global pandemic. The Company is continuing to proactively monitor the COVID-19 global pandemic, to assess the potential impact on the business, and to seek to avoid any unnecessary potential delays to the Company’s programs. As of September 30, 2021, the clinical programs and research activities remain largely on track, with some modest delays in clinical trial enrollment rates and supply chain activities. While we are unable to fully quantify the potential effects of this pandemic on our future operations, including potential delays to our preclinical and clinical programs, management continues to evaluate and to seek to mitigate risks. The safety and well-being of employees, patients and partners remains our highest priority.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

References to the unaudited interim combined financial statements of the Centessa Predecessor Group refer to three of the eleven Centessa Subsidiaries that were deemed to represent the predecessor entity prior to the Company’s acquisition of the Centessa Subsidiaries in January 2021. The Centessa Predecessor Group includes the combined financial information of Z Factor, Morphogen-IX and LockBody. The successor includes the consolidated financial information of Centessa and all Centessa Subsidiaries subsequent to the acquisition.

Accordingly, the accompanying unaudited interim consolidated and combined financial statements are presented in accordance with Securities and Exchange Commission (“SEC”) requirements for predecessor and successor financial statements, which include the financial results of both the Company and the Centessa Predecessor Group. The results of operations contained in the unaudited interim consolidated and combined financial statements include the Centessa Predecessor Group’s combined financial results for the three and nine months ended September 30, 2020, and the period from January 1, 2021 through January 29, 2021 and the Company’s consolidated financial results for the three months ended September 30, 2021 and for period from January 30, 2021 through September 30, 2021. The unaudited interim consolidated and combined balance sheets present the combined financial position of the Centessa Predecessor Group as of December 31, 2020 and the consolidated financial position of the Company on September 30, 2021.

The accompanying unaudited interim consolidated and combined financial statements should be read in conjunction with the annual audited combined financial statements of the Centessa Predecessor Group (Predecessor) and related notes as of and for the year ended December 31, 2020 and accompanying audited financial statements of Centessa Pharmaceuticals Limited

and related notes as of December 31, 2020 found in the prospectus filed with the SEC on June 2, 2021. The Summary of Significant Accounting Policies included in the Company’s annual financial statements and the Centessa Predecessor Group’s annual combined financial statements that can be found in the prospectus, have not materially changed, except as set forth below.

Basis of Presentation and Combination / Consolidation

The accompanying unaudited interim consolidated and combined financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) promulgated by the Financial Accounting Standards Board (“FASB”).

In the opinion of management, the accompanying unaudited interim consolidated and combined financial statements include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the financial statements) considered necessary to present fairly:

•the Company’s financial position as of September 30, 2021 and the Predecessor’s financial position as of December 31, 2020;

•the Company’s results of operations for the three months ended September 30, 2021 and the period from January 30, 2021 through September 30, 2021, and cash flows for the period from January 30, 2021 through September 30, 2021; and

•the Predecessor’s results of operations for the period from January 1, 2021 through January 29, 2021 and for the three and nine month periods ended September 30, 2020, and cash flows for the period from January 1, 2021 through January 29, 2021 and nine months ended September 30, 2020.

Operating results for the Company from the period from January 30, 2021 through September 30, 2021 are not necessarily indicative of the results that may be expected for the period from January 30, 2021 through December 31, 2021, or for any future period. The unaudited interim consolidated and combined financial statements, presented herein, do not contain all of the required disclosures under U.S. GAAP for annual financial statements. Therefore, these unaudited interim consolidated and combined financial statements should be read in conjunction with the annual audited combined financial statements and related notes for Centessa Pharmaceuticals Limited and Centessa Predecessor Group found in the prospectus filed with the SEC on June 2, 2021.

The Company’s unaudited interim consolidated financial statements include the accounts of Centessa Pharmaceuticals plc, its wholly-owned subsidiary, Centessa Pharmaceuticals, Inc. and the wholly-owned Centessa Subsidiaries. The Centessa Predecessor Group’s unaudited interim combined financial statements included the accounts of Z Factor, Morphogen-IX and LockBody. All intercompany accounts and transactions have been eliminated in consolidation and combination.

Segments

Operating segments are defined as components of an enterprise with separate discrete information available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Centessa Pharmaceuticals plc (Successor) and the Centessa Predecessor Group (Predecessor) view its operations and manage its business as one segment.

Reclassifications

Certain amounts in the prior period financial statements have been reclassified to conform to the presentation of the current period financial statements. These reclassifications had no effect on previously reported net loss or comprehensive loss.

Foreign Currency Translation

The Company’s financial statements are presented in U.S. dollars (USD), the reporting currency of the Company. The functional currency of the Centessa Pharmaceuticals plc is USD and the functional currency of the Centessa Subsidiaries is their

respective local currency. Income and expenses have been translated into USD at average exchange rates prevailing during the period. Assets and liabilities have been translated at the rates of exchange on the balance sheets dates and equity accounts at their respective historical rates. The resulting translation gain and loss adjustments are recorded directly as a separate component of shareholders’ equity as other comprehensive income (loss). Transactions denominated in a currency other than the functional currency are remeasured based upon the exchange rate at the date of remeasurement with the resulting gain or loss included in the accompanying unaudited interim consolidated and combined statements of operations and comprehensive loss within Other income (expense), net.

Since its formation in October 2020, the functional currency of Centessa Pharmaceuticals plc had been British pounds (GBP), as Centessa Pharmaceutical plc’s primary activities were formation, related transaction costs, primarily denominated in GBP, the acquisition of Centessa subsidiaries predominantly with operations in GBP and the issuance of shares (with a GBP nominal value) as consideration in the acquisition.

Beginning as of the second quarter of 2021, the functional currency of Centessa Pharmaceuticals plc, changed from GBP to USD. The change in functional currency is the result of many factors including the completion of an IPO and receipt of proceeds in USD which resulted in USD denominated assets exceeding GBP denominated assets, the increase in its U.S. based employees, and the increase in costs denominated in USD, following completion of the Company’s IPO on a U.S. stock exchange (Nasdaq). Given these significant changes, the Company considered the economic factors outlined in ASC 830, Foreign Currency Matters and concluded that the majority of the factors supported the use of the USD as the functional currency for Centessa Pharmaceutical plc.

The change in functional currency for Centessa Pharmaceuticals plc was applied on a prospective basis beginning as of the second quarter of 2021 and translation adjustments for prior periods will continue to remain as a component of accumulated other comprehensive loss. The Company reclassified the presentation of foreign currency gains and losses recognized in the first quarter of 2021 from General & administration expense to Other income (expense), net to conform to the current period financial statement presentation.

Use of Estimates

The preparation of unaudited interim financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the unaudited interim consolidated and combined financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates.

Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the unaudited interim consolidated and combined financial statements in the period they are determined to be necessary. Significant areas that require management’s estimates include share-based compensation assumptions, derivative liability and contingent value rights assumptions, accrued research and development expenses, and, prior to the IPO, the fair value of the Company’s ordinary shares.

Property and Equipment, net

Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives of three years. The costs of maintenance and repairs are expensed as incurred. Improvements and betterment that add new functionality or extend the useful life of the asset are capitalized. As of September 30, 2021, the Company had $114,000 of property and equipment, net and primarily comprised of computer equipment. Depreciation expense was $15,744 and $22,551 for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively.

Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, then an impairment charge is recognized for the

amount by which the carrying value of the asset exceeds the estimated fair value of the asset. As of September 30, 2021, the Company believes that no revision of the remaining useful lives or write-down of long-lived assets is required.

Contingent Value Rights

The fair value of the contingent value rights liability represents the estimated future payments that will be settled by issuing a variable number of shares and that are contingent upon the achievement of a specified development milestone for Palladio Biosciences, Inc.’s product candidate. The fair value of the contingent value rights is based on the cumulative probability of achieving the specified milestone which is currently expected by the first quarter of 2022. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestone, anticipated timelines, and discount rate. Changes in the fair value of the liability are recognized in the consolidated statement of operations and comprehensive loss until it is settled.

Acquired In-Process Research and Development Expenses

Acquired in-process research and development (“IPR&D”), consists of the initial up-front payments incurred in connection with the acquisition or licensing of products or technologies in transactions that do not meet the definition of a business under FASB ASC Topic 805, Business Combinations.

Share-Based Compensation

The Company and the Predecessor measure share-based awards at their grant-date fair value and record compensation expense on a straight-line basis over the vesting period of the awards.

Estimating the fair value of share-based awards requires the input of subjective assumptions, including the estimated fair value of the Company and the Predecessor’s ordinary shares, and, for stock options, the expected life of the options and share price volatility. The Company and the Predecessor account for forfeitures of stock option awards as they occur. The Company uses the Black-Scholes option pricing model to value its stock option awards. The assumptions used in estimating the fair value of share-based awards represent management’s estimate and involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, share-based compensation expense could be materially different for future awards.

The expected life of the stock options is estimated using the “simplified method,” as the Company has limited historical information from which to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants. The simplified method is the midpoint between the vesting period and the contractual term of the option. For share price volatility, the Company uses comparable public companies as a basis for its expected volatility to calculate the fair value of option grants. The risk-free rate is based on the U.S. Treasury yield curve commensurate with the expected life of the option.

Awards granted for ordinary shares of Centessa Pharmaceuticals plc (Successor) are accounted for as restricted share-based awards. The estimated fair value of the restricted shares is based upon the estimated fair value of Centessa Pharmaceutical plc’s (Successor) ordinary shares at grant date.

Net Loss Per Ordinary Share

Basic loss per ordinary share is computed by dividing net loss by the aggregate weighted-average number of ordinary shares outstanding. Diluted loss per ordinary share includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred shares, stock options, unvested restricted ordinary shares and convertible debt which would result in the issuance of incremental ordinary shares. For diluted net loss per ordinary share, the weighted-average number of ordinary shares is the same for basic net loss per ordinary share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive.

The following potentially dilutive securities have been excluded from the computation of diluted weighted-average ordinary shares outstanding for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, as they would be anti-dilutive.


Unvested ordinary shares			987,361
Stock options			10,755,205
			11,742,566

Recently Issued Accounting Pronouncements

In July 2021, the FASB issued ASU 2021-05, Lease (Topic 842): Lessors - Certain Leases with Variable Lease Payments ("ASU 2021-05"). The guidance in ASU 2021-05 amends the lease classification requirements for the lessors under certain leases containing variable payments to align with practice under ASC 840. The lessor should classify and account for a lease with variable lease payments that do not depend on a reference index or a rate as an operating lease if both of the following criteria are met: 1) the lease would have been classified as a sales-type lease or a direct financing lease in accordance with the classification criteria in ASC 842-10-25-2 through 25-3; and 2) the lessor would have otherwise recognized a day-one loss. The amendments in ASU 2021-05 are effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company is currently evaluating the impact of adoption to the unaudited interim consolidated and combined financial statements and related disclosures.

In May 2021, the FASB issued ASU 2021-04, Issuer's Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options, ("ASU 2021-04") which clarifies the accounting for modifications or exchanges of freestanding equity-classified written call options that remain equity classified after modification or exchange. Specifically, ASU 2021-04 requires the issuer to treat a modification of an equity-classified warrant as an exchange of the original warrant. The difference between the fair value of the modified warrant and the fair value of the warrant immediately before modification is then recognized as an issuance cost or discount of the related transaction. ASU 2021-04 is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years, with early adoption permitted. ASU 2021-04 should be applied prospectively to modifications or exchanges occurring after the effective date. Either the full or modified retrospective adoption method is allowed. We do not have any equity-classified written call options that would be subject to this guidance. Therefore, we do not expect any impact on the Company's unaudited interim consolidated and combined financial statements and related disclosures.

In October 2020, the FASB issued ASU 2020-10-Codification Improvements. For public business entities, the amendments in this update are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The amendments in this update do not change U.S. GAAP and, therefore, are not expected to result in a significant change in practice. Section A was removed from the final update of ASU 2020-10. Section B of this update contains amendments that improve the consistency of the Codification by including all disclosure guidance in the appropriate Disclosure Section (Section 50). Section C of this update contains Codification improvements that vary in nature. The Company adopted ASU 2020-10 on January 30, 2021 and it did not have a material impact to the Company’s unaudited interim consolidated and combined financial statements and related disclosures.

In August 2020, the FASB issued ASU 2020-06, “(Subtopic 470-20): Debt—Debt with Conversion and Other Options” (“ASU 2020-06”) to address the complexity associated with applying GAAP to certain financial instruments with characteristics of liabilities and equity. ASU 2020-06 includes amendments to the guidance on convertible instruments and the derivative scope exception for contracts in an entity’s own equity and simplifies the accounting for convertible instruments which include beneficial conversion features or cash conversion features by removing certain separation models in Subtopic 470-20. Additionally, ASU 2020-06 will require entities to use the “if-converted” method when calculating diluted earnings per share for convertible instruments. ASU 2020-06 is effective for fiscal years beginning after December 15, 2023 (fiscal year 2024 for the Group), including interim periods within those fiscal years. The Company is currently evaluating the impact of ASU 2020-06 to the unaudited interim consolidated and combined financial statements and related disclosures.

In March 2020, the FASB issued ASU 2020-03, “Codification Improvements to Financial Instruments”: The amendments in this update are to clarify, correct errors in, or make minor improvements to a variety of ASC topics. The changes in ASU 2020-03 are not expected to have a significant effect on current accounting practices. The ASU improves various financial instrument topics in the Codification to increase stakeholder awareness of the amendments and to expedite the improvement process by making the Codification easier to understand and easier to apply by eliminating inconsistencies and providing clarifications. The ASU is effective for smaller reporting companies for fiscal years beginning after December 15, 2022 with early application permitted. The Company is currently evaluating the impact the adoption of this guidance may have on its unaudited interim consolidated and combined financial statements.

In December 2019, the FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes,” which is intended to simplify various aspects related to accounting for income taxes. ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021. The Company is currently evaluating ASU 2019-12 and its impact on the unaudited interim consolidated and combined financial statements.

In February 2016, the FASB issued ASU No. 2016-02, Leases, which requires a lessee to record a right-of-use asset and a corresponding lease liability on the balance sheet for all leases with terms longer than 12 months. A modified retrospective transition approach is required for lessees for finance and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. As the Company has elected to use the extended transition period for complying with new or revised accounting standards as available under the JOBS Act, the standard is effective for the Company beginning January 1, 2022, with early adoption permitted. The Company is currently evaluating the impact of adoption to the unaudited interim consolidated and combined financial statements and related disclosures.

Acquisition of Centessa Subsidiaries

9 Months Ended

Sep. 30, 2021

Business Combination and Asset Acquisition [Abstract]

Acquisition of Centessa Subsidiaries

In January 2021, the Company entered into a contribution or merger agreement with each Centessa Subsidiary whereby the Company acquired 100% of the outstanding Centessa Subsidiaries’ shares in exchange for, in aggregate, 44,758,079 ordinary shares of the Company. In addition, the Company issued certain contingent value rights to the selling shareholders of Palladio Biosciences, Inc.

As part of the acquisition, the Company issued replacement equity awards to select employees and consultants of certain Centessa Subsidiaries. The awards consisted of options and restricted shares with vesting provisions generally consistent with the original awards prior to the acquisition. The Company determined that a portion of the fair value of the replacement awards should be a component of consideration paid to acquire the Centessa Subsidiaries, with the remaining value of the award accounted for as post-combination share-based compensation expense.

The acquisition of each Centessa Subsidiary has been treated as a separate asset acquisition as the Company determined that none of the Centessa Subsidiaries meet the definition of a business due to substantially all of the fair value of each entity being concentrated in a single asset or group of assets which represent the IPR&D or the entity did not have the requisite inputs and substantive processes to be considered a business. The Company’s acquired IPR&D expense of $223.6 million, of which $3.1 million was in connection with transaction costs recognized prior to January 30, 2021, and reflects the fair value of consideration ascribed to the product candidates in each subsidiary, as the Company determined the assets had no alternative future use.

The total purchase price for the asset acquisitions was calculated as follows (amounts in thousands):


Estimated fair value of Centessa ordinary shares issued	$	261,387
Estimated fair value of replacement equity awards allocated to consideration paid	1,310
Estimated fair value of contingent value rights	22,618
Transaction costs	4,597
Total consideration given	$	289,912

The following table summarizes the assets acquired and liabilities assumed as of the acquisition date for the asset acquisitions (in thousands):


Assets acquired:
Cash and cash equivalents	$	68,038
Tax incentive receivable	8,752
Prepaid expenses and other current assets	2,551
Other assets	203
In-process research and development assets	223,593
Total assets acquired	303,137


Liabilities assumed:
Accounts payable	3,607
Accrued expenses and other current liabilities	3,128
Convertible notes	6,199
Loan with related party	291
Total liabilities assumed	13,225
Net assets acquired	$	289,912

The Company’s determinations of the fair value of the ordinary shares were performed using methodologies, approaches and assumptions in accordance with the guidance outlined in the American Institute of Certified Public Accountants’ Accounting and Valuation Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation, (“Practice Guide”). In accordance with the Practice Guide, the Company (Successor) considered the following methods for allocating the enterprise value across its classes and series of capital shares to determine the fair value of its ordinary shares at each valuation date.

•Option Pricing Method (“OPM”). The OPM estimates the value of the ordinary equity of the Company using the various inputs in the Black-Scholes option pricing model. The OPM treats the rights of the holders of ordinary shares as equivalent to that of call options on any value of the enterprise above certain break points of value based upon the liquidation preferences of the holders of the Company’s convertible preferred shares, as well as their rights to participation, and the share prices of the outstanding options. Thus, the value of the ordinary shares can be determined by estimating the value of its portion of each of these call option rights. Under this method, the ordinary shares have value only if the funds available for distribution to shareholders exceed the value of the liquidation preference at the time of a liquidity event, such as a merger or sale. Given the ordinary shares represents a non-marketable equity interest in a private enterprise, an adjustment to the preliminary value estimates had to be made to account for the lack of liquidity that a shareholder experiences. This adjustment is commonly referred to as a discount for lack of marketability (“DLOM”).

•Probability-Weighted Expected Return Method (“PWERM”). The PWERM is a scenario-based analysis that estimates the value per share based on the probability-weighted present value of expected future investment returns, considering each of the possible outcomes considered by the Company, as well as the economic and control rights of each share class.

•Hybrid Method. The Hybrid Method is a hybrid between the PWERM and OPM, estimating the probability-weighted value across multiple scenarios, but using the OPM to estimate the allocation of value within one or more of those scenarios. Weighting allocations are assigned to the OPM and PWERM methods factoring possible future liquidity events.

The Company estimated the fair value of its ordinary shares based on the Hybrid Method. Subjective factors considered by the Company’s board of directors and management included the pending addition of new executive members and the election of new independent directors to the Company’s board of directors, as well as definitive plans to undertake an IPO. There are significant judgments and estimates inherent in the determination of the fair value of ordinary shares. These judgments and estimates include assumptions regarding the Company’s future operating performance, the time to complete an initial public offering or other liquidity event and the determination of the appropriate valuation methods. If the Company had made different assumptions, its ordinary shares could have been significantly different.

At the time of the acquisitions, all outstanding unvested share-based awards of the Centessa Predecessor Group vested immediately. The unrecognized compensation expense of $4.1 million was recognized at the time of the acquisitions.

In connection with the acquisition of the Centessa Subsidiaries, the Company issued contingent value rights (CVR), to former shareholders and option holders of Palladio. The CVR represent the contractual rights to receive payment of $39.7 million upon the first patient dosed in a Phase 3 pivotal study of lixivaptan for the treatment of autosomal dominant polycystic kidney disease (“ADPKD”) in any of the United States, France, Germany, Italy, Spain, the United Kingdom and Japan (designated the ACTION Study). The contingent CVR milestone, if triggered, will be settled through the issuance of the

Company’s ordinary shares equal to the amount of the total CVR payable based on the per share value of ordinary shares at the milestone date.The Company determined that the CVR should be accounted for as a liability in accordance with ASC 480. Accordingly, the fair value of the contingent consideration is assessed quarterly until settlement. To estimate the fair value of the contingent consideration, the Company applied a cumulative probability of achieving the clinical milestone and applied it to the potential payout. While the Company will consider the status and on-going results of the Phase 3a safety study (designated the ALERT Study), an open-label study for which enrollment is on-going, the Company intends to commence the Phase 3 pivotal study (designated the ACTION Study) in parallel with the ALERT Study. Therefore, the probability of commencing the ACTION Study and dosing the first patient is high and the milestone is currently expected by the first quarter of 2022. The cumulative probability of dosing the first patient in the ACTION Study was applied to the CVR payout to arrive at a fair value of $22.6 million as of the acquisition date of the Centessa Subsidiaries. The change in fair value from the date of acquisition to September 30, 2021 of $11.3 million is reflected in the consolidated and combined statement of operations and comprehensive loss, and results in a fair value of the CVR liability as of September 30, 2021 of $33.9 million.

Fair Value Measurement

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurement

Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments be made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including prepaid expense and accounts payable are shown at cost, which approximates fair value due to the short-term nature of these instruments. The Company follows the provisions of FASB ASC Topic 820, Fair Value Measurement, for financial assets and liabilities measured on a recurring basis. The guidance requires fair value measurements be classified and disclosed in one of the following three categories:

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

Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities.

Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).

The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis (in thousands):


	Fair value measurement at reporting date using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
September 30, 2021 (Successor)
Liabilities
Contingent Value Rights	$	—	$	—	$	33,930


	Fair value measurement at reporting date using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
December 31, 2020 (Predecessor)
Liabilities
Derivative liability	$	—	$	—	$	913

The Centessa Predecessor Group evaluated a redemption feature within the convertible term notes and determined bifurcation of the redemption feature was required. The redemption feature is classified as a liability on the accompanying consolidated and combined balance sheet at December 31, 2020. The liability is marked-to-market each reporting period with the changes in fair value recorded in the unaudited interim consolidated and combined statements of operations and comprehensive loss until it is settled. The derivative liability was considered a Level 3 liability because its fair value measurement was based, in part, on significant inputs not observed in the market. The fair value of the derivative was estimated primarily on the probability of the next fund raising occurring and the timing of such event. Upon completion of the acquisition of the Centessa Subsidiaries in January 2021, the derivative liability was settled and is no longer subject to remeasurement.

The acquisition-date fair value of the contingent valuation rights liability represents the future payments that are contingent upon the achievement of a specified development milestone for Palladio’s product candidate. The fair value of the contingent value rights is based on the cumulative probability of achieving the specified milestone which is currently expected by the first quarter of 2022. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestone, anticipated timelines, and discount rate. Changes in the fair value of the liability will be recognized in the unaudited interim consolidated and combined statement of operations and comprehensive loss until it is settled.

The reconciliation of the redemption feature measured at fair value on a recurring basis using significant unobservable inputs (Level 3) is as follows (amounts in thousands):


	Contingent Value Rights		Derivative Liability
Balance at January 1, 2021 (Predecessor)	$	—	$	913
Additions	—		—
Change in fair value	—		—
Settlements	—		(913)
Balance at January 29, 2021 (Predecessor)	$	—	$	—
Balance at January 30, 2021 (Successor)	$	—	$	—
Additions	22,618		—
Balance at March 31, 2021 (Successor)	22,618		—
Change in fair value of contingent value rights	11,312		—
Balance at June 30, 2021 (Successor)	$	33,930	$	—
Change in fair value of contingent value rights	—		—
Balance at September 30, 2021 (Successor)	$	33,930	$	—

- 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

Balance Sheet and Combined Deficit Components

9 Months Ended

Sep. 30, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet and Combined Deficit Components

Balance Sheet and Combined Deficit ComponentsPrepaid expenses and other current assets consist of the following (in thousands):


	Successor		Predecessor
	September 30, 2021		December 31, 2020
D&O Insurance	$	7,995	$	9
Value added tax receivable	2,945		298
Research and development costs	2,229		992
Other	1,050		6
	$	14,219	$	1,305

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


	Successor		Predecessor
	September 30, 2021		December 31, 2020
Research and development expenses	5,194		1,001
Personnel related expenses	2,936		—
Professional fees	2,324		37
Other	234		9
	$	10,688	$	1,047

Combined deficit of the Centessa Predecessor Group at December 31, 2020 consisted of the following (in thousands):


	Predecessor
	December 31, 2020
Morphogen-IX deficit
Ordinary shares	$	13
Additional paid-in capital	364
Accumulated other comprehensive income	629
Accumulated deficit	(9,225)
Total Morphogen-IX deficit	$	(8,219)
Z Factor deficit
Ordinary shares	$	12
Additional paid-in capital	461
Accumulated other comprehensive income	139
Accumulated deficit	(8,568)
Total Z Factor deficit	$	(7,956)
LockBody deficit
Ordinary shares	$	—
Additional paid-in capital	—
Accumulated other comprehensive income (loss)	(196)
Accumulated deficit	(6,052)
Total LockBody deficit	$	(6,248)
Total combined deficit	$	(22,423)

Debt	9 Months Ended
Debt	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt Centessa Pharmaceuticals Limited Convertible Term Notes In December 2020, the Company entered into a convertible loan agreement (the Agreement) with Medicxi Growth, whereby the Company issued $5.0 million of unsecured convertible term notes to Medicxi Growth. The convertible loans were issued as a bridge financing in contemplation of completing the Series A financing. The convertible term notes had a stated interest rate of 8% per annum, which was not payable until settlement of the principal, being the maturity date June 29, 2021. Upon completion of the Company’s Series A preferred financing in January 2021, the Company issued 568,181 shares of its Series A convertible preferred shares and settled all outstanding principal and unpaid interest associated with the convertible term notes. LockBody Therapeutics Ltd Convertible Term Notes In July 2019, LockBody entered into a convertible term note agreement to issue up to £5.0 million of convertible term notes of which £3.0 million was received in July 2019 and an additional £1.0 million was received in November 2020. The convertible term notes had a stated interest rate of 2% per annum, which was not payable until settlement of the principal, being the maturity date of August 2, 2021. The principal and accrued interest due under the convertible term notes converts: •into the class of LockBody’s shares issued in LockBody’s next qualified fund raising, at a conversion price after applying a 20% discount to the purchase price per share paid for the shares. •on a change of control, at a conversion price after applying a 50% discount to the purchase price per share paid for the shares. As a result of the fact that the convertible term notes were convertible into a variable number of preferred shares, the Centessa Predecessor Group evaluated the conversion provision as a redemption feature. The redemption feature was evaluated as an embedded derivative and bifurcated from the convertible term notes due to the substantial premium paid upon redemption and accounted for as a derivative instrument. Upon bifurcating the redemption feature, the Group recorded aggregate debt discounts of $0.7 million that is recognized in interest expense over the term of the convertible term notes. The notes and the derivative liability were assumed in connection with the acquisition of the Centessa Subsidiaries in January 2021 and immediately forgiven. The forgiveness was recognized as $6.2 million contribution within the Successor consolidated statement of shareholders’ equity during the period from January 30, 2021 through September 30, 2021.

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

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

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments As of September 30, 2021, the Company had non-cancellable commitments for purchase of clinical materials, contract manufacturing, maintenance, and committed funding of up to $17.1 million, of which the Company expects to pay $15.9 million within one year and the remaining $1.2 million over one to three years. The amount and timing of these payments vary depending on the rate of progress of development. Future clinical trial expenses have not been included within the purchase commitments because they are contingent on enrollment in clinical trials and the activities required to be performed by the clinical sites. Contingencies From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of its business activities. The Company accrues a liability for such matters when it is probable that future expenditures will be made, and such expenditures can be reasonably estimated. Litigation The Company, to its knowledge, is not a party to any litigation as of September 30, 2021, that, if determined adversely, would have a material adverse effect on its business and operations.

Convertible Preferred Shares	9 Months Ended
Convertible Preferred Shares	Sep. 30, 2021
Equity [Abstract]
Convertible Preferred Shares	Convertible Preferred Shares As of December 31, 2020, the Centessa Predecessor Group had Series A, Series B and Seed Series convertible preferred shares outstanding that were subject to redemption under certain “deemed liquidation” events, as defined in each of the Centessa Predecessor Group entities’ articles of association. The Series A, Series B and Seed Series convertible preferred shares are classified outside of combined deficit as the deemed liquidation events are outside of the each of the Centessa Predecessor Group entities’ control. Upon consummation of the acquisition of the Centessa Subsidiaries, all outstanding convertible preferred shares of the Centessa Predecessor Group were converted into ordinary shares of the Centessa Predecessor Group and ultimately were exchanged for ordinary shares of Centessa Pharmaceuticals Limited at the time of acquisition. Immediately following the acquisition, the Centessa Subsidiaries became wholly-owned subsidiaries of the Centessa Pharmaceuticals Limited whereby no convertible preferred shares were issued and outstanding at the Centessa Subsidiaries level. Ordinary Shares Ordinary shares confer upon its holders voting rights, the right to receive cash and stock dividends, if declared, and the right to share in excess assets upon liquidation of the Company. The holders of ordinary shares are entitled to one vote per share. In January 2021, the Company issued 45,137,984 ordinary shares in connection with the acquisition of the Centessa Subsidiaries of which 379,905 shares were replacement share-based awards and subject to future vesting requirements. Concurrent with the acquisition, the Company repurchased 4,450,000 of its A ordinary shares from several of its founders for a nominal amount. Series A Convertible Preferred Shares In January 2021, the Company sold 22,272,721 shares of its Series A convertible preferred shares at a purchase price of $11.00 per share in exchange for gross proceeds of $245.0 million. Upon completion of the Series A preferred financing, the Company issued 568,181 Series A convertible preferred shares upon settling the outstanding principal, unpaid interest, and bifurcated derivative liability associated with its convertible term notes. Dividends The holders of Preferred Shares are entitled to dividends if and when declared by the Company’s board of directors. As of September 30, 2021, no dividends have been declared and no Preferred Shares are outstanding. Voting Each preferred share is entitled to a vote on an as-converted basis and certain significant Group events require majority approval from the preferred shareholders as a separate class. Conversion Each preferred share is convertible, at the holder’s option, into such number of ordinary shares on a one-to-one basis and equal to the conversion price then in effect. The conversion price is subject to adjustments for splits, dividends, distributions and other similar recapitalization events. Upon consummation of a qualified initial public offering of the Company’s securities, the preferred shares would automatically convert into ordinary shares. Liquidation Preference Upon the liquidation, sale, or merger of the Company (collectively, the Liquidation), the preferred shareholders are entitled to receive an amount equal to the original issuance price plus any unpaid declared dividends. If there are additional available assets from the liquidation after the initial liquidation payments, the remaining available assets will be distributed to the ordinary shareholders.

Share-based Compensation

9 Months Ended

Sep. 30, 2021

Share-based Payment Arrangement [Abstract]

Share-based Compensation

The Company and the Centessa Predecessor Group recorded share-based compensation expense in the following expense categories in the unaudited interim consolidated and combined statements of operations and comprehensive loss (in thousands):


	Successor				Predecessor
	Three Months Ended September 30, 2021		Period from January 30, 2021 through September 30, 2021		Period from January 1, 2021 through January 29, 2021		Three Months Ended September 30, 2020		Nine Months Ended September 30, 2020
Research and development	$	1,572	$	3,613	$	—	$	29	$	245
General and administrative	2,561		6,480		—		—		—
	$	4,133	$	10,093	$	—	$	29	$	245

Centessa Pharmaceuticals plc (Successor) Stock Options

In January 2021, the Company’s board of directors approved the 2021 Equity Incentive Plan (the 2021 Plan). The number of shares authorized under the 2021 Plan was increased in May 2021 at the time of the IPO, whereby the total number of shares authorized under the 2021 Plan was 19,192,910 of which 8,437,705 shares were available for future grants as of September 30, 2021. The Plan provides for the granting of ordinary shares, incentive stock options, non-qualified stock options, restricted share awards, and/or share appreciation rights to employees, directors, and other persons, as determined by the Company’s board of directors. The Company’s stock options vest based on the terms in each award agreement, generally over four-year periods, and have a contractual term of ten years.

The following table summarizes stock option activity for the period from January 30, 2021 through September 30, 2021:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term
Balance at January 30, 2021	—
Granted	11,792,647	$	7.36
Exercised	(50,000)	$	5.84
Forfeited	(987,442)	$	6.29
Balance at September 30, 2021	10,755,205	$	7.47	9.3
Exercisable at September 30, 2021	574,267	$	4.66	7.5

The weighted-average grant date fair value of options granted was $7.47 per share for the period from January 30, 2021 through September 30, 2021. As of September 30, 2021, the total unrecognized compensation expense related to unvested stock option awards was $43.0 million, which the Company expects to recognize over a weighted-average period of 2.2 years.

Based on the trading price of $16.70 per ADS, which is the closing price as of September 30, 2021, the aggregate intrinsic value of options as of September 30, 2021 was $101.9 million, of which $7.0 million is related to vested options.

During the period from January 30, 2021 through September 30, 2021, the fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below:


Expected term (in years)	5.85
Expected stock price volatility	65.69	%
Risk-free interest rate	0.85	%
Expected dividend yield	0	%
Estimated fair value of ordinary share	$7.47

Restricted Share Awards

In connection with the acquisition of the Centessa Subsidiaries, the Company issued 379,905 ordinary shares subject to future vesting. In the nine months ended September 30, 2021, the Company issued an additional 833,897 ordinary shares subject to future vesting to an employee. The fair value of the awards are based upon the estimated fair value of the Company’s ordinary shares at the time of grant.

The following table summarizes ordinary share activity for the period from January 30, 2021 through September 30, 2021:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
Unvested at January 30, 2021	—
Granted	1,213,802	$	15.57
Vested	(226,441)	$	5.84
Unvested at September 30, 2021	987,361	$	17.80

As of September 30, 2021, the total unrecognized compensation expense related to unvested ordinary shares was $15.6 million, which the Company expects to recognize over a weighted-average period of 2.4 years.

Licensing Arrangements	9 Months Ended
Licensing Arrangements	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Licensing Arrangements	Licensing Arrangements In connection with the acquisition of the Centessa Subsidiaries, the Company acquired the following licensing arrangements: Z Factor Limited License Agreement In 2015 and subsequently amended in 2017, Z Factor entered into an exclusive worldwide license agreement to further develop and commercialize, small molecule chaperones to correct the folding of Z-A1AT, which Z Factor is currently developing for the treatment of liver and lung disease The Group is solely responsible for, and is required to use commercially reasonable efforts to, research, develop, manufacture and commercialize the licensed technology, at its own costs. The Group is also responsible for supplying all active pharmaceutical ingredients and finished drug product for exploitation. The Group is obligated to make up to $0.5 million (£0.4 million at an exchange rate of 0.74) in payments upon the achievement of development and regulatory milestones. In addition, the Group is obligated to fund any patent related costs associated with the licensed technology. No expenses were incurred during the three months ended September 30, 2021 and 2020, the period from January 1, 2021 through January 29, 2021, the period from January 30, 2021 through September 30, 2021 and the nine months ended September 30, 2020 in connection with the license agreement. Morphogen-IX Limited License Agreement In 2015, Morphogen-IX entered into an exclusive worldwide license agreement to further develop and commercialize variants of BMP9. The Company is responsible for supplying all active pharmaceutical ingredients and finished drug product for exploitation. The Company is obligated to make up to $1.1 million (£0.8 million at an exchange rate of 0.74) in payments upon the achievement of development and regulatory milestones. The Company is also obligated to make future commercial milestone payments at low to mid-single digit royalty rates for net product sales and is subject to adjustment in the event the Group sublicenses the approved technology. In addition, the Company is obligated to pay an annual licensing fee and obligated to fund any patent related costs associated with the licensed technology. No expenses were incurred during the three months ended September 30, 2021 and 2020, the period from January 1, 2021 through January 29, 2021 and the period from January 30, 2021 through September 30, 2021 in connection with the license agreement. Palladio Biosciences Inc. Lixivaptan License Agreement Palladio entered into an exclusive worldwide license agreement to further develop and commercialize Lixivaptan, a nonpeptide selective vasopressin V2 receptor antagonist which Palladio is currently developing for the treatment of ADPKD. In relation to the purchase of the license, the Company is obligated to make certain contingent consideration payments to the seller in the event a Licensed Product is commercialized. Such payments are structured as a tiered percentage of net sales and capped at $32.5 million. The Company is obligated to make up to $16.3 million in commercial milestone payments. In addition, the Company is obligated to make future royalty payments (the first $19.0 million of which would be due to Pfizer) at low to mid-single digit royalty rates for net product sales and is subject to adjustment in the event the Company sublicenses the approved technology. The Company incurred no expense during the period from January 30, 2021 through September 30, 2021 in connection with the license agreement. ApcinteX Limited SerpinPC License Agreement ApcinteX entered into an exclusive, sublicensable, worldwide license agreement with Cambridge Enterprise Limited (“CE”), to further develop and commercialize the patented technology and know-how held by CE for modified serpins for the treatment of bleeding disorders through the use of rational and random mutagenesis associated with the patented technology. The Company is solely responsible for, and is required to use commercially reasonable efforts to, research, develop, manufacture and commercialize the patented technology, at its own costs. The Company is obligated to make up to $0.9 million (£0.7 million at an exchange rate of 0.74) in development and regulatory milestone payments and low single digit royalty rates for net product sales. The Company incurred no expense during the period from January 30, 2021 through September 30, 2021 in connection with the license agreement. Pega-One S.A.S. License Agreement with Hoffman-La Roche Pega-One entered into, and subsequently amended, a license agreement with Hoffman La Roche Ltd, (“Roche”), to discover, develop and commercialize GA201 which is a glycoengineered anti-EGFR monoclonal antibody imgatuzumab which Pega-One is currently developing for the treatment of cutaneous squamous cell carcinoma and other solid tumor indications. The Company retains an exclusive worldwide sublicensable royalty bearing license. Pega-One made an upfront payment of $2.0 million and is obligated to pay up to $16.0 million upon the achievement of development and regulatory milestones and up to $125.0 million in commercial milestones subject to potential increase if Pega-One undergoes a change in control transaction before a specified event for a specific indication. Pega-One is also obligated to pay Roche tiered royalties on net sales of the licensed product at rates ranging from a mid to high single percentage, on a country-by-country and product-by-product basis and is subject to adjustments in the event the Company sublicenses the approved technology. In addition, Pega-One is obligated to reimburse Roche for annual patent related costs incurred related to the license. Upon consummation of a strategic transaction or an initial public offering of the Pega-One’s ordinary shares, as defined in the license agreement, Roche is entitled to receive a minimum of 10% of the consideration received by the Company. Such consideration was received in connection with the acquisition of the Centessa Subsidiaries in January 2021. Janpix Limited License Agreement Janpix entered into an exclusive worldwide license agreement to further develop and commercialize the licensed technology for therapeutic use. Janpix is obligated to make up to $30.0 million in development and commercial milestone payments. In addition, Janpix is obligated to make future commercial milestone payments at low to mid-single digit royalty rates for net product sales. Capella Biosciences Limited License Agreement Capella entered into a license agreement with Lonza Sales AG (“Lonza”) to utilize Lonza’s proprietary GS technology to further develop, manufacture, market and sell Capella’s compounds for therapeutic use. Capella is obligated to make additional payments contingent upon approval to advance through additional stages of the process. Capella is obligated to make up to $5.4 million in development and commercial milestone payments. Capella is also obligated to make future commercial royalty payments at low single digit royalty rates for net product sales and is subject to adjustment in the event Capella sublicenses the approved technology. The Company incurred approximately $42,060 and $116,960 in expense related to the license agreement during the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively. PearlRiver Bio GmbH License and Collaboration Agreement with Lead Discovery Center GmbH for Exon20 In March 2019, PearlRiver Bio GmbH entered into an exclusive worldwide license agreement with Lead Discovery Center GmbH (“LDC”), to further develop and commercialize, the licensed technology for Exon20. PearlRiver is responsible for supplying all active pharmaceutical ingredients and finished drug products for exploitation. PearlRiver is obligated to make up to $31.4 million (€27.0 million) at an exchange rate of 0.86) in payments upon the achievement of development and regulatory milestones and $17.4 million (€15.0 million) at an exchange rate of 0.86) upon the achievement of commercial milestones. PearlRiver is also obligated to make future commercial royalty payments at low to mid-single digit royalty rates for net product sales and is subject to adjustment in the event PearlRiver sublicenses the approved technology. In addition, PearlRiver is obligated to fund any patent related costs associated with the licensed technology. Concurrent with entering into the license agreement, PearlRiver entered into a collaboration arrangement with LDC whereby LDC is providing ongoing research and development services to PearlRiver. PearlRiver recognizes research and development expenses associated with the collaboration as services are provided. PearlRiver Bio GmbH Assignment Agreement with Lead Discovery Center GmbH for C797 PearlRiver entered into an exclusive worldwide assignment agreement with Lead Discovery Center GmbH (“LDC”), to further develop and commercialize, the assigned technology for C797. PearlRiver is responsible for supplying all active pharmaceutical ingredients and finished drug products for exploitation. PearlRiver is obligated to make up to $9.1 million (€7.8 million at an exchange rate of 0.86) in payments upon the achievement of development and regulatory milestones and $11.6 million (€10.0 million at an exchange rate of 0.86) upon the achievement of commercial milestones. PearlRiver is also obligated to make future commercial milestone payments at low single digit royalty rates for net product sales and is subject to adjustment in the event the PearlRiver sublicenses the approved technology. In addition, PearlRiver is obligated to fund any patent related costs associated with the licensed technology. Orexia Therapeutics Limited Research Collaboration and License Agreement Orexia entered into a world-wide exclusive research collaboration and license agreement with X-Chem, Inc (“X-Chem”), to further develop and commercialize, the licensed technology for the orexin receptor. Orexia is responsible for supplying all active pharmaceutical ingredients and finished drug products for exploitation. Orexia is required to make payments contingent upon approval to advance to particular series. Orexia is obligated to make up to $24.8 million in payments upon the achievement of development and regulatory milestones and $60 million upon the achievement of commercial milestones. Orexia is also obligated to make future commercial milestone payments at low single digit royalty rates for net product sales and is subject to adjustment in the event the Orexia sublicenses the approved technology. Orexia Therapeutics Limited Amended and Restated License, Assignment, and Research Services Agreement In January 2019, Orexia entered into an exclusive worldwide license agreement with Heptares Therapeutics Limited (“Heptares”), to further develop and commercialize, the licensed technology for orexin agonist. Orexia is responsible for supplying all active pharmaceutical ingredients and finished drug product for exploitation. Orexia is obligated to make up to $17.0 million (£12.6 million at an exchange rate of 0.74) in payments upon the achievement of development and regulatory milestones. Orexia is also obligated to make future commercial milestone payments at low to mid-single digit royalty rates for net product sales and is subject to adjustment in the event the Orexia sublicenses the approved technology. In addition, Orexia is obligated to fund any development related costs associated with the licensed technology. Inexia Limited Amended and Restated License, Assignment, and Research Services Agreement Inexia and Heptares entered into a license and research service agreement whereby Heptares granted an exclusive, sublicensable worldwide license to further develop, manufacture and commercialize licensed technology for the development of intranasal orexin antagonist. In addition, Heptares is responsible for certain research and development activities and the parties formed a joint research committee to oversee and manage related research and development activities. Per the agreement Inexia is to pay Heptares for research and development services based on providing full-time equivalents and other support relating to the conduct of the discovery and preclinical development programs. In addition, Inexia is obligated to make up to $16.4 million in development milestone payments (£12.1 million at an exchange rate of 0.74). In April 2021, Orexia, Inexia and the Company executed an Intra Group Sales Agreement whereby Inexia assigned the rights to its business and assets (including these licenses) to Orexia for nil consideration. Inexia Limited License Agreement with OptiNose Inexia and OptiNose AS (“OptiNose”), entered into a license agreement whereby the Inexia was granted an exclusive, royalty-bearing, worldwide, non-transferable, sublicensable license to OptiNose’s Exhalation Delivery System (“EDS”), and other intellectual property for the development, sale, import and manufacture of products containing orexin receptor agonist and/or orexin receptor positive modulator molecule(s) as the sole active pharmaceutical ingredient(s) for the treatment, diagnosis or prevention of human diseases or conditions associated primarily with orexin receptor agonism and orexin receptor positive modulation. Inexia is solely responsible for all costs and activities related to its identification, development, and commercialization of products under the license agreement. Inexia is obligated to make up to $8.0 million and $37.0 million in development and commercial milestone payments, respectively. In addition, OptiNose is eligible to receive tiered, low-to-mid single digit royalties based on net sales of any products successfully developed and commercialized under the license agreement. In April 2021, Orexia, Inexia and the Company executed an Intra Group Sales Agreement whereby Inexia assigned the rights to its business and assets (including these licenses) to Orexia for nil consideration.

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Term loans with Ultrahuman The Centessa Predecessor Group entered into term loan agreements with Ultrahuman Nine and Ultrahuman Ten which are entities with common ownership with the Centessa Predecessor Group and with the Company. The term loans have a stated interest rate of 2% per annum above the Bank of England official rate and the outstanding balances are repayable on demand of the lenders. The Bank of England official rate was 0.10% at September 30, 2020 and 2021, respectively. The outstanding balance of the term loan with Ultrahuman Eleven was forfeited by the lender in February 2020, from which a gain on extinguishment of debt of $264,000 is recognized in the combined statements of operations and comprehensive loss for Centessa Predecessor Group during the nine months ended September 30, 2020. The outstanding balance of the term loans with Ultrahuman Nine and Ultrahuman Ten was cancelled in June 2021. During the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, the Centessa Predecessor Group recognized interest expense of $2,500, $5,000, and $1,000, respectively, in connection with the Ultrahuman loans. During the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, the Company recognized interest expense of nil and $3,000, respectively, in connection with the loans. The loans were repaid in May 2021. Support service agreement with Ultrahuman services The Centessa Predecessor Group entered into a Support Service Agreement with Ultrahuman Limited. Ultrahuman Limited provides scientific and operational consultancy services and other support services. Costs incurred associated with this contract were $0.2 million, $0.6 million, and $48,000 for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively, which has been recorded within research and development expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. The contract was terminated in connection with the acquisition of the Centessa Subsidiaries. Master services agreements with The Cambridge Partnership Limited The Centessa Predecessor Group entered into Master Services agreements with The Cambridge Partnership Limited for accounting and administrative services. Costs incurred associated with these contracts were $29,000, $77,000, and $17,000 for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively, which has been recorded within general and administrative expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. The Company (Successor) incurred costs associated with these contracts of $39,000, and $0.2 million for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively. The agreement was terminated by mutual consent of the parties in August 2021. David Grainger is a director and shareholder in RxCelerate Ltd, the ultimate controlling party of The Cambridge Partnership Limited and was a director of Z Factor and Morphogen-IX until he resigned on January 29, 2021. He was appointed Chief Innovation Officer of the Company in October 2021. Master services agreements with The Foundry (Cambridge) Limited The Centessa Predecessor Group entered into Master Services agreements with The Foundry (Cambridge) Limited. Costs incurred associated with these contracts were $12,000, $34,000, and $4,000 for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively, and which has been recorded within general and administrative expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. The Company (Successor) incurred costs associated with these contracts of $10,000, and $31,000 for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively. David Grainger is a director and the sole shareholder of The Foundry (Cambridge) Limited and was a director of Z Factor and Morphogen-IX until he resigned on January 29, 2021. He was appointed Chief Innovation Officer of the Company in October 2021. Master Services agreements with RxCelerate Limited The Centessa Predecessor Group entered into Master Services agreements with RxCelerate Limited to provide drug discovery services. Costs incurred associated with this contract were $0.8 million, $2.5 million, and $0.4 million for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively, which has been recorded within research and development expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. The Company (Successor) incurred costs associated with these contracts of $1.9 million and $5.2 million for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively. David Grainger is a director and shareholder of RxCelerate Limited and was a director of Z Factor and Morphogen-IX until he resigned on January 29, 2021. He was appointed Chief Innovation Officer of the Company in October 2021. Master Services agreements with RxBiologics Limited The Centessa Predecessor Group entered into Master Services agreements with RxBiologics Limited to provide biologics drug discovery services. Costs incurred associated with this contract were $40,000, $67,000, and $14,000 for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively, which has been recorded within research and development expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. The Company (Successor) incurred costs associated with these contracts of $0.1 million and $0.3 million for the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, respectively. William Finlay is a director and shareholder of RxBiologics Limited and was a director of LockBody until he resigned on January 29, 2021. David Grainger is a director of RxBiologics Limited and a director and shareholder in RxCelerate Ltd, as noted above, the ultimate controlling party of RxBiologics Limited and was a director of Z Factor and Morphogen-IX until he resigned on January 29, 2021. He was appointed Chief Innovation Officer of the Company in October 2021. Master Services agreements with Cambridge Protein Works Limited The Centessa Predecessor Group entered into Services agreements with Cambridge Protein Works Limited to provide pure proteins for research and development purposes. Costs incurred associated with this contract were $57,000, $68,000, and nil for the three and nine months ended September 30, 2020 and for the period from January 1, 2021 through January 29, 2021, respectively. For the three months ended September 30, 2021 and for the period from January 30, 2021 through September 30, 2021, the Company incurred costs of $0.2 million and $0.3 million which has been recorded within research and development expenses in the unaudited interim consolidated and combined statements of operations and comprehensive loss. Jim Huntington is a director and shareholder of Cambridge Protein Works Limited and is the Chief Executive Officer of ApcinteX and Z Factor. Cost Reimbursements During the period from January 30, 2021 through September 30, 2021, the Company (Successor) reimbursed an aggregate of $1.4 million to several shareholders for costs paid on behalf of the Company (Successor) in connection with acquisition of the Centessa Subsidiaries and the sale of the Company (Successor) Series A preferred shares.

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 1, 2021 (the “Signing Date”), the Company, as issuer, and certain of the Company’s wholly owned subsidiaries, as guarantors (the “Guarantors”), entered into a Note Purchase Agreement (the “Note Purchase Agreement”) with the Purchasers party thereto (the “Purchasers”), and Cocoon SA LLC (the “Agent”), an affiliate of Oberland Capital Management LLC, as agent for the Purchasers. Under the Note Purchase Agreement, the Purchasers agreed to purchase, and the Company agreed to sell, tranches of secured notes in the aggregate principal amount of up to $300,000,000 as follows: (a) no later than October 4, 2021, a secured note in the aggregate principal amount of $75,000,000 (the “First Purchase Note”), (b) on and after the Signing Date until September 30, 2023, at the Company’s option, a secured note in the aggregate principal amount of $75,000,000 (the “Second Purchase Note”), (c) on and after the Signing Date until September 30, 2023, at the Company’s option, a secured note in the aggregate principal amount of $50,000,000 (the “Third Purchase Note”), and (d) one or more secured notes in the aggregate principal amount of up to $100,000,000 at any time at the Company’s and Purchasers’ option, to be used to finance certain permitted acquisitions as described in the Note Purchase Agreement (the “Fourth Purchase Notes” and collectively with the First Purchase Note, the Second Purchase Note and the Third Purchase Note, the “Notes”). The obligations of the Purchasers to purchase the Notes are subject to certain conditions precedent. On October 4, 2021 (the “First Purchase Date”), the Company issued the First Purchase Note. The Notes will mature on the six-year anniversary of the First Purchase Date, unless earlier accelerated under the terms of the Note Purchase Agreement. At maturity, the Company must repay the outstanding principal amount of the Notes, together with any accrued and unpaid interest thereon and other outstanding obligations thereunder. Interest is payable quarterly during the term of the Notes at a rate per annum equal to the sum of (a) the greater of (i) LIBOR (which may be subject to replacement as contemplated by the Note Purchase Agreement) and (ii) 0.25% and (b) 7.75% (which percentage is subject to adjustment as described in the Note Purchase Agreement); provided that the interest rate shall never be less than 8.00%. The initial interest rate for the Notes is 8.00% per annum. The Company’s obligations under the facility are secured by a first priority security interest in all assets of the Company and Guarantors, subject to variation in accordance with local law with respect to assets held by the Company and the Guarantors outside of the United States. Starting on the date of the first commercial sale of lixivaptan, currently a product candidate under development by the Company, and ending on the tenth anniversary of the First Purchase Date, the Purchasers shall have the right to receive 1.00% (the “Revenue Participation Rate”) of the first $200.0 million of worldwide net sales of lixivaptan in each calendar year, payable quarterly (the “Revenue Participation Payments”). The Revenue Participation Rate is subject to pro-rata increase if the Second Purchase Notes and/or the Third Purchase Notes are issued and shall not exceed 2.67%. In addition, upon the first regulatory approval of any of the Company’s product candidates by either the U.S. Food and Drug Administration (“FDA”) or the European Medicines Agency (“EMA”), the Company is obligated to pay the Purchasers an amount equal to 30% of the aggregate principal amount issued under the Notes by the Company (the “Milestone Payment”). The Milestone Payment shall be paid in quarterly installments over five years beginning on the earlier of (i) the date of the first commercial sale following such regulatory approval; and (ii) the six month anniversary of such regulatory approval. The Milestone Payment is triggered one time only, and applies only to the Company’s first product to obtain regulatory approval. The Company may redeem all, but not less than all, of the outstanding Notes (if any) and pay all other outstanding obligations under the Note Purchase Agreement. On the applicable date, the Company shall repurchase the Notes by paying an amount of up to (i) 175% of the principal amount issued under the Notes if such repurchase occurs on or prior to the third anniversary of the First Purchase Date, (ii) 185% of the principal amount issued under the Notes if such repurchase occurs between the third and sixth anniversaries of the First Purchase Date, and (iii) 205% of the principal amount issued under the Notes if such repurchase occurs thereafter, in each case less specified deductions and exclusions described in the Note Purchase Agreement, including amounts paid by the Company to the Purchasers in respect of certain asset sale or strategic transactions, the interest payments, the Revenue Participation Payments and the Milestone Payments (the “Final Payment Amount”). Conversely, the Purchasers may require the Company to redeem any outstanding Notes by payment of the Final Payment Amount upon a sale, divestment or transfer of all or substantially all assets of the Company in a transaction or series of transactions or a change of control of the Company, a material breach of the Note Purchase Agreement and related transaction documents, an event of default under the Note Purchase Agreement or the tenth anniversary of the First Purchase Date (or such earlier date as described in the Note Purchase Agreement). In addition, upon certain asset sales and similar strategic transactions by the Company with respect to its own or its subsidiaries’ assets or businesses as described in the Note Purchase Agreement (other than a change of control described above), the Purchasers may require the Company to pay an amount in cash equal to up to 75% of the Net Proceeds (as defined in the Note Purchase Agreement) received from such asset sales, subject to such reduced amounts as described in the Note Purchase Agreement. The Note Purchase Agreement contains customary affirmative and negative covenants, including with respect to notice obligations, limitations on new indebtedness, liens, investments and transactions with affiliates of the Company, restrictions on the payment of dividends, maintenance of collateral accounts, maintenance of insurance and addition of new subsidiaries as obligors. The Note Purchase Agreement does not contain any covenants to maintain a specified level of revenues or cash resources. The Note Purchase Agreement also contains customary representations and warranties in favor of the Purchasers and the Agent. The Note Purchase Agreement contains customary events of default, which may cause the obligations of the Company to be accelerated. Such events include among others, failure to make payments when due, breach of covenants, insolvency, a cross-default to other indebtedness, a judgment event of default, and delisting of the Company’s securities from Nasdaq.

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation and Combination/Consolidation	Basis of Presentation and Combination / Consolidation The accompanying unaudited interim consolidated and combined financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) promulgated by the Financial Accounting Standards Board (“FASB”). In the opinion of management, the accompanying unaudited interim consolidated and combined financial statements include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the financial statements) considered necessary to present fairly: •the Company’s financial position as of September 30, 2021 and the Predecessor’s financial position as of December 31, 2020; •the Company’s results of operations for the three months ended September 30, 2021 and the period from January 30, 2021 through September 30, 2021, and cash flows for the period from January 30, 2021 through September 30, 2021; and •the Predecessor’s results of operations for the period from January 1, 2021 through January 29, 2021 and for the three and nine month periods ended September 30, 2020, and cash flows for the period from January 1, 2021 through January 29, 2021 and nine months ended September 30, 2020. Operating results for the Company from the period from January 30, 2021 through September 30, 2021 are not necessarily indicative of the results that may be expected for the period from January 30, 2021 through December 31, 2021, or for any future period. The unaudited interim consolidated and combined financial statements, presented herein, do not contain all of the required disclosures under U.S. GAAP for annual financial statements. Therefore, these unaudited interim consolidated and combined financial statements should be read in conjunction with the annual audited combined financial statements and related notes for Centessa Pharmaceuticals Limited and Centessa Predecessor Group found in the prospectus filed with the SEC on June 2, 2021. The Company’s unaudited interim consolidated financial statements include the accounts of Centessa Pharmaceuticals plc, its wholly-owned subsidiary, Centessa Pharmaceuticals, Inc. and the wholly-owned Centessa Subsidiaries. The Centessa Predecessor Group’s unaudited interim combined financial statements included the accounts of Z Factor, Morphogen-IX and LockBody. All intercompany accounts and transactions have been eliminated in consolidation and combination.
Segments	Segments Operating segments are defined as components of an enterprise with separate discrete information available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Centessa Pharmaceuticals plc (Successor) and the Centessa Predecessor Group (Predecessor) view its operations and manage its business as one segment.
Reclassifications	Reclassifications Certain amounts in the prior period financial statements have been reclassified to conform to the presentation of the current period financial statements. These reclassifications had no effect on previously reported net loss or comprehensive loss.
Foreign Currency Translation	Foreign Currency Translation The Company’s financial statements are presented in U.S. dollars (USD), the reporting currency of the Company. The functional currency of the Centessa Pharmaceuticals plc is USD and the functional currency of the Centessa Subsidiaries is their respective local currency. Income and expenses have been translated into USD at average exchange rates prevailing during the period. Assets and liabilities have been translated at the rates of exchange on the balance sheets dates and equity accounts at their respective historical rates. The resulting translation gain and loss adjustments are recorded directly as a separate component of shareholders’ equity as other comprehensive income (loss). Transactions denominated in a currency other than the functional currency are remeasured based upon the exchange rate at the date of remeasurement with the resulting gain or loss included in the accompanying unaudited interim consolidated and combined statements of operations and comprehensive loss within Other income (expense), net. Since its formation in October 2020, the functional currency of Centessa Pharmaceuticals plc had been British pounds (GBP), as Centessa Pharmaceutical plc’s primary activities were formation, related transaction costs, primarily denominated in GBP, the acquisition of Centessa subsidiaries predominantly with operations in GBP and the issuance of shares (with a GBP nominal value) as consideration in the acquisition. Beginning as of the second quarter of 2021, the functional currency of Centessa Pharmaceuticals plc, changed from GBP to USD. The change in functional currency is the result of many factors including the completion of an IPO and receipt of proceeds in USD which resulted in USD denominated assets exceeding GBP denominated assets, the increase in its U.S. based employees, and the increase in costs denominated in USD, following completion of the Company’s IPO on a U.S. stock exchange (Nasdaq). Given these significant changes, the Company considered the economic factors outlined in ASC 830, Foreign Currency Matters and concluded that the majority of the factors supported the use of the USD as the functional currency for Centessa Pharmaceutical plc. The change in functional currency for Centessa Pharmaceuticals plc was applied on a prospective basis beginning as of the second quarter of 2021 and translation adjustments for prior periods will continue to remain as a component of accumulated other comprehensive loss. The Company reclassified the presentation of foreign currency gains and losses recognized in the first quarter of 2021 from General & administration expense to Other income (expense), net to conform to the current period financial statement presentation.
Use of Estimates	Use of Estimates The preparation of unaudited interim financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the unaudited interim consolidated and combined financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates. Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the unaudited interim consolidated and combined financial statements in the period they are determined to be necessary. Significant areas that require management’s estimates include share-based compensation assumptions, derivative liability and contingent value rights assumptions, accrued research and development expenses, and, prior to the IPO, the fair value of the Company’s ordinary shares.
Property and Equipment, net	Property and Equipment, netProperty and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives of three years. The costs of maintenance and repairs are expensed as incurred. Improvements and betterment that add new functionality or extend the useful life of the asset are capitalized.
Long-Lived Assets	Long-Lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, then an impairment charge is recognized for the amount by which the carrying value of the asset exceeds the estimated fair value of the asset. As of September 30, 2021, the Company believes that no revision of the remaining useful lives or write-down of long-lived assets is required.
Contingent Value Rights	Contingent Value Rights The fair value of the contingent value rights liability represents the estimated future payments that will be settled by issuing a variable number of shares and that are contingent upon the achievement of a specified development milestone for Palladio Biosciences, Inc.’s product candidate. The fair value of the contingent value rights is based on the cumulative probability of achieving the specified milestone which is currently expected by the first quarter of 2022. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestone, anticipated timelines, and discount rate. Changes in the fair value of the liability are recognized in the consolidated statement of operations and comprehensive loss until it is settled.
Acquired In-Process Research and Development Expenses	Acquired In-Process Research and Development Expenses Acquired in-process research and development (“IPR&D”), consists of the initial up-front payments incurred in connection with the acquisition or licensing of products or technologies in transactions that do not meet the definition of a business under FASB ASC Topic 805, Business Combinations.
Share-Based Compensation	Share-Based Compensation The Company and the Predecessor measure share-based awards at their grant-date fair value and record compensation expense on a straight-line basis over the vesting period of the awards. Estimating the fair value of share-based awards requires the input of subjective assumptions, including the estimated fair value of the Company and the Predecessor’s ordinary shares, and, for stock options, the expected life of the options and share price volatility. The Company and the Predecessor account for forfeitures of stock option awards as they occur. The Company uses the Black-Scholes option pricing model to value its stock option awards. The assumptions used in estimating the fair value of share-based awards represent management’s estimate and involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, share-based compensation expense could be materially different for future awards. The expected life of the stock options is estimated using the “simplified method,” as the Company has limited historical information from which to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants. The simplified method is the midpoint between the vesting period and the contractual term of the option. For share price volatility, the Company uses comparable public companies as a basis for its expected volatility to calculate the fair value of option grants. The risk-free rate is based on the U.S. Treasury yield curve commensurate with the expected life of the option. Awards granted for ordinary shares of Centessa Pharmaceuticals plc (Successor) are accounted for as restricted share-based awards. The estimated fair value of the restricted shares is based upon the estimated fair value of Centessa Pharmaceutical plc’s (Successor) ordinary shares at grant date.
Net Loss Per Ordinary Share	Net Loss Per Ordinary Share Basic loss per ordinary share is computed by dividing net loss by the aggregate weighted-average number of ordinary shares outstanding. Diluted loss per ordinary share includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred shares, stock options, unvested restricted ordinary shares and convertible debt which would result in the issuance of incremental ordinary shares. For diluted net loss per ordinary share, the weighted-average number of ordinary shares is the same for basic net loss per ordinary share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In July 2021, the FASB issued ASU 2021-05, Lease (Topic 842): Lessors - Certain Leases with Variable Lease Payments ("ASU 2021-05"). The guidance in ASU 2021-05 amends the lease classification requirements for the lessors under certain leases containing variable payments to align with practice under ASC 840. The lessor should classify and account for a lease with variable lease payments that do not depend on a reference index or a rate as an operating lease if both of the following criteria are met: 1) the lease would have been classified as a sales-type lease or a direct financing lease in accordance with the classification criteria in ASC 842-10-25-2 through 25-3; and 2) the lessor would have otherwise recognized a day-one loss. The amendments in ASU 2021-05 are effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company is currently evaluating the impact of adoption to the unaudited interim consolidated and combined financial statements and related disclosures. In May 2021, the FASB issued ASU 2021-04, Issuer's Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options, ("ASU 2021-04") which clarifies the accounting for modifications or exchanges of freestanding equity-classified written call options that remain equity classified after modification or exchange. Specifically, ASU 2021-04 requires the issuer to treat a modification of an equity-classified warrant as an exchange of the original warrant. The difference between the fair value of the modified warrant and the fair value of the warrant immediately before modification is then recognized as an issuance cost or discount of the related transaction. ASU 2021-04 is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years, with early adoption permitted. ASU 2021-04 should be applied prospectively to modifications or exchanges occurring after the effective date. Either the full or modified retrospective adoption method is allowed. We do not have any equity-classified written call options that would be subject to this guidance. Therefore, we do not expect any impact on the Company's unaudited interim consolidated and combined financial statements and related disclosures. In October 2020, the FASB issued ASU 2020-10-Codification Improvements. For public business entities, the amendments in this update are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The amendments in this update do not change U.S. GAAP and, therefore, are not expected to result in a significant change in practice. Section A was removed from the final update of ASU 2020-10. Section B of this update contains amendments that improve the consistency of the Codification by including all disclosure guidance in the appropriate Disclosure Section (Section 50). Section C of this update contains Codification improvements that vary in nature. The Company adopted ASU 2020-10 on January 30, 2021 and it did not have a material impact to the Company’s unaudited interim consolidated and combined financial statements and related disclosures. In August 2020, the FASB issued ASU 2020-06, “(Subtopic 470-20): Debt—Debt with Conversion and Other Options” (“ASU 2020-06”) to address the complexity associated with applying GAAP to certain financial instruments with characteristics of liabilities and equity. ASU 2020-06 includes amendments to the guidance on convertible instruments and the derivative scope exception for contracts in an entity’s own equity and simplifies the accounting for convertible instruments which include beneficial conversion features or cash conversion features by removing certain separation models in Subtopic 470-20. Additionally, ASU 2020-06 will require entities to use the “if-converted” method when calculating diluted earnings per share for convertible instruments. ASU 2020-06 is effective for fiscal years beginning after December 15, 2023 (fiscal year 2024 for the Group), including interim periods within those fiscal years. The Company is currently evaluating the impact of ASU 2020-06 to the unaudited interim consolidated and combined financial statements and related disclosures. In March 2020, the FASB issued ASU 2020-03, “Codification Improvements to Financial Instruments”: The amendments in this update are to clarify, correct errors in, or make minor improvements to a variety of ASC topics. The changes in ASU 2020-03 are not expected to have a significant effect on current accounting practices. The ASU improves various financial instrument topics in the Codification to increase stakeholder awareness of the amendments and to expedite the improvement process by making the Codification easier to understand and easier to apply by eliminating inconsistencies and providing clarifications. The ASU is effective for smaller reporting companies for fiscal years beginning after December 15, 2022 with early application permitted. The Company is currently evaluating the impact the adoption of this guidance may have on its unaudited interim consolidated and combined financial statements. In December 2019, the FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes,” which is intended to simplify various aspects related to accounting for income taxes. ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021. The Company is currently evaluating ASU 2019-12 and its impact on the unaudited interim consolidated and combined financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases, which requires a lessee to record a right-of-use asset and a corresponding lease liability on the balance sheet for all leases with terms longer than 12 months. A modified retrospective transition approach is required for lessees for finance and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. As the Company has elected to use the extended transition period for complying with new or revised accounting standards as available under the JOBS Act, the standard is effective for the Company beginning January 1, 2022, with early adoption permitted. The Company is currently evaluating the impact of adoption to the unaudited interim consolidated and combined financial statements and related disclosures.

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2021

Accounting Policies [Abstract]

Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-Average Ordinary Shares Outstanding


Unvested ordinary shares			987,361
Stock options			10,755,205
			11,742,566

Acquisition of Centessa Subsidiaries (Tables)

9 Months Ended

Sep. 30, 2021

Business Combination and Asset Acquisition [Abstract]

Asset Acquisition

The total purchase price for the asset acquisitions was calculated as follows (amounts in thousands):


Estimated fair value of Centessa ordinary shares issued	$	261,387
Estimated fair value of replacement equity awards allocated to consideration paid	1,310
Estimated fair value of contingent value rights	22,618
Transaction costs	4,597
Total consideration given	$	289,912

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed

The following table summarizes the assets acquired and liabilities assumed as of the acquisition date for the asset acquisitions (in thousands):


Assets acquired:
Cash and cash equivalents	$	68,038
Tax incentive receivable	8,752
Prepaid expenses and other current assets	2,551
Other assets	203
In-process research and development assets	223,593
Total assets acquired	303,137


Liabilities assumed:
Accounts payable	3,607
Accrued expenses and other current liabilities	3,128
Convertible notes	6,199
Loan with related party	291
Total liabilities assumed	13,225
Net assets acquired	$	289,912

Fair Value Measurement (Tables)

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis (in thousands):


	Fair value measurement at reporting date using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
September 30, 2021 (Successor)
Liabilities
Contingent Value Rights	$	—	$	—	$	33,930


	Fair value measurement at reporting date using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
December 31, 2020 (Predecessor)
Liabilities
Derivative liability	$	—	$	—	$	913

Reconciliation of the Redemption Feature Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs

The reconciliation of the redemption feature measured at fair value on a recurring basis using significant unobservable inputs (Level 3) is as follows (amounts in thousands):


	Contingent Value Rights		Derivative Liability
Balance at January 1, 2021 (Predecessor)	$	—	$	913
Additions	—		—
Change in fair value	—		—
Settlements	—		(913)
Balance at January 29, 2021 (Predecessor)	$	—	$	—
Balance at January 30, 2021 (Successor)	$	—	$	—
Additions	22,618		—
Balance at March 31, 2021 (Successor)	22,618		—
Change in fair value of contingent value rights	11,312		—
Balance at June 30, 2021 (Successor)	$	33,930	$	—
Change in fair value of contingent value rights	—		—
Balance at September 30, 2021 (Successor)	$	33,930	$	—

Balance Sheet and Combined Deficit Components (Tables)

9 Months Ended

Sep. 30, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Prepaid Expenses and Other Current Assets

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


	Successor		Predecessor
	September 30, 2021		December 31, 2020
D&O Insurance	$	7,995	$	9
Value added tax receivable	2,945		298
Research and development costs	2,229		992
Other	1,050		6
	$	14,219	$	1,305

Schedule of Accrued Expenses and Other Current Liabilities

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


	Successor		Predecessor
	September 30, 2021		December 31, 2020
Research and development expenses	5,194		1,001
Personnel related expenses	2,936		—
Professional fees	2,324		37
Other	234		9
	$	10,688	$	1,047

Schedule of Combined Deficit

Combined deficit of the Centessa Predecessor Group at December 31, 2020 consisted of the following (in thousands):


	Predecessor
	December 31, 2020
Morphogen-IX deficit
Ordinary shares	$	13
Additional paid-in capital	364
Accumulated other comprehensive income	629
Accumulated deficit	(9,225)
Total Morphogen-IX deficit	$	(8,219)
Z Factor deficit
Ordinary shares	$	12
Additional paid-in capital	461
Accumulated other comprehensive income	139
Accumulated deficit	(8,568)
Total Z Factor deficit	$	(7,956)
LockBody deficit
Ordinary shares	$	—
Additional paid-in capital	—
Accumulated other comprehensive income (loss)	(196)
Accumulated deficit	(6,052)
Total LockBody deficit	$	(6,248)
Total combined deficit	$	(22,423)

Share-based Compensation (Tables)

9 Months Ended

Sep. 30, 2021

Share-based Payment Arrangement [Abstract]

Summary of Share-based Compensation Expense


	Successor				Predecessor
	Three Months Ended September 30, 2021		Period from January 30, 2021 through September 30, 2021		Period from January 1, 2021 through January 29, 2021		Three Months Ended September 30, 2020		Nine Months Ended September 30, 2020
Research and development	$	1,572	$	3,613	$	—	$	29	$	245
General and administrative	2,561		6,480		—		—		—
	$	4,133	$	10,093	$	—	$	29	$	245

Summary of Stock Option Activity

The following table summarizes stock option activity for the period from January 30, 2021 through September 30, 2021:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term
Balance at January 30, 2021	—
Granted	11,792,647	$	7.36
Exercised	(50,000)	$	5.84
Forfeited	(987,442)	$	6.29
Balance at September 30, 2021	10,755,205	$	7.47	9.3
Exercisable at September 30, 2021	574,267	$	4.66	7.5

Schedule of Assumptions Used to Estimate Fair Value of Stock Option Awards

During the period from January 30, 2021 through September 30, 2021, the fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below:


Expected term (in years)	5.85
Expected stock price volatility	65.69	%
Risk-free interest rate	0.85	%
Expected dividend yield	0	%
Estimated fair value of ordinary share	$7.47

Summary of Replacement Equity Award Activity

The following table summarizes ordinary share activity for the period from January 30, 2021 through September 30, 2021:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
Unvested at January 30, 2021	—
Granted	1,213,802	$	15.57
Vested	(226,441)	$	5.84
Unvested at September 30, 2021	987,361	$	17.80

Organization and Description of Business (Details)		1 Months Ended		9 Months Ended
Organization and Description of Business (Details)	Oct. 01, 2021 USD ($)	Oct. 31, 2021 USD ($)	Jun. 30, 2021 USD ($) shares	Sep. 30, 2021 USD ($)	Oct. 04, 2021 USD ($)	Sep. 30, 2021 £ / shares	Jun. 30, 2021 £ / shares shares	Jun. 30, 2021 $ / shares shares	Dec. 31, 2020 USD ($)	Dec. 31, 2020 £ / shares
Subsidiary, Sale of Stock [Line Items]
Number of ordinary shares per American Depositary Shares (ADSs) (in shares) \| shares							1	1
Common stock, nominal value (in pound sterling per share) \| £ / shares						£ 0.002	£ 0.002			£ 0.002
Aggregate net proceeds in connection with the IPO and subsequent exercise of the underwriter's options			$ 344,100,000
Accumulated deficit				$ (324,879,000)
Sufficient funding term (at least)				12 months
Cash and cash equivalents				$ 578,815,000					$ 7,227,000
Oberland Capital \| Subsequent Event
Subsidiary, Sale of Stock [Line Items]
Note purchase agreement, value	$ 300,000,000	$ 300,000,000
Note purchase agreement, amount funded					$ 75,000,000
Note purchase agreement, amount available for funding at the option of the Company		$ 125,000,000
Note purchase agreement, term for available funding		24 months
Note purchase agreement, amount available for funding at the option of the Company and Oberland Capital		$ 100,000,000
Net proceeds					$ 74,600,000
Oberland Capital \| Subsequent Event \| Senior Notes
Subsidiary, Sale of Stock [Line Items]
Debt instrument, term	6 years
Stated interest rate	8.00%
Oberland Capital \| Subsequent Event \| Interest Only, Senior Secured Notes \| Senior Notes
Subsidiary, Sale of Stock [Line Items]
Debt instrument, term		6 years
Stated interest rate		8.00%
IPO
Subsidiary, Sale of Stock [Line Items]
Shares sold in offering (in shares) \| shares			16,500,000
Share price (in dollars per share) \| $ / shares								$ 20.00
Over-Allotment Option
Subsidiary, Sale of Stock [Line Items]
Shares sold in offering (in shares) \| shares			2,475,000
Share price (in dollars per share) \| $ / shares								$ 20.00

Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended	8 Months Ended	9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($) segment	Dec. 31, 2020 USD ($)
Accounting Policies [Abstract]
Number of operating segments \| segment			1
Property and equipment useful life			3 years
Property and equipment, net	$ 114,000	$ 114,000	$ 114,000	$ 0
Depreciation expense	$ 15,744	$ 22,551

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-Average Ordinary Shares Outstanding (Details) - shares	3 Months Ended	8 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted-average ordinary shares outstanding (in shares)	11,742,566	11,742,566
Ordinary Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted-average ordinary shares outstanding (in shares)	987,361	987,361
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted-average ordinary shares outstanding (in shares)	10,755,205	10,755,205

Acquisition of Centessa Subsidiaries - Additional Information (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended		8 Months Ended		9 Months Ended
	Jan. 29, 2021	Jan. 29, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Asset Acquisition [Line Items]
Contingent value rights			$ 33,930		$ 33,930	$ 33,930		$ 0
Change in fair value of contingent value rights		$ 0	0	$ 0	11,312	11,312	$ 0
Centessa Subsidiaries
Asset Acquisition [Line Items]
Percentage of outstanding shares acquired	100.00%	100.00%
Acquisition of Centessa Subsidiaries (in shares)	44,758,079
In-process research and development assets	$ 223,593
Transaction costs	4,597	$ 3,100
Unrecognized compensation expense	4,100	4,100
Contingent consideration arrangements, range of outcomes, high			39,700		39,700	39,700
Contingent value rights	$ 22,600	$ 22,600	$ 33,900		$ 33,900	33,900
Change in fair value of contingent value rights						$ 11,300

Acquisition of Centessa Subsidiaries - Asset Acquisition (Details) - Centessa Subsidiaries - USD ($) $ in Thousands		1 Months Ended
	Jan. 29, 2021	Jan. 29, 2021
Asset Acquisition [Line Items]
Estimated fair value of Centessa ordinary shares issued	$ 261,387
Estimated fair value of replacement equity awards allocated to consideration paid	1,310
Estimated fair value of contingent value rights	22,618
Transaction costs	4,597	$ 3,100
Total consideration given	$ 289,912

Acquisition of Centessa Subsidiaries - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Details) - Centessa Subsidiaries $ in Thousands	Jan. 29, 2021 USD ($)
Assets acquired:
Cash and cash equivalents	$ 68,038
Tax incentive receivable	8,752
Prepaid expenses and other current assets	2,551
Other assets	203
In-process research and development assets	223,593
Total assets acquired	303,137
Liabilities assumed:
Accounts payable	3,607
Accrued expenses and other current liabilities	3,128
Convertible notes	6,199
Loan with related party	291
Total liabilities assumed	13,225
Net assets acquired	$ 289,912

Fair Value Measurement - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Quoted prices in active markets for identical assets (Level 1)
Liabilities
Contingent value rights	$ 0
Derivative liability		$ 0
Significant other observable inputs (Level 2)
Liabilities
Contingent value rights	0
Derivative liability		0
Significant unobservable inputs (Level 3)
Liabilities
Contingent value rights	$ 33,930
Derivative liability		$ 913

Fair Value Measurement - Reconciliation of the Redemption Feature Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended
	Jan. 29, 2021	Mar. 31, 2021	Sep. 30, 2021	Jun. 30, 2021
Derivative Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 913	$ 0
Additions	0
Change in fair value	0
Settlements	(913)
Ending balance	0
Contingent Value Rights
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance		0	$ 33,930	$ 22,618
Additions		22,618
Change in fair value			0	11,312
Ending balance	$ 0	$ 22,618	$ 33,930	$ 33,930

Balance Sheet and Combined Deficit Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
D&O Insurance	$ 7,995	$ 9
Value added tax receivable	2,945	298
Research and development costs	2,229	992
Other	1,050	6
Prepaid expenses and other current assets	$ 14,219	$ 1,305

Balance Sheet and Combined Deficit Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development expenses	$ 5,194	$ 1,001
Personnel related expenses	2,936	0
Professional fees	2,324	37
Other	234	9
Accrued expenses and other current liabilities	$ 10,688	$ 1,047

Balance Sheet and Combined Deficit Components - Schedule of Combined Deficit (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 29, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Schedule of Combined Deficit [Line Items]
Ordinary shares	$ 252
Additional paid-in capital	871,022
Accumulated other comprehensive income (loss)	2,738
Accumulated deficit	$ (324,879)
Total combined deficit		$ (23,145)	$ (22,423)	$ (19,349)	$ (17,612)	$ (15,512)	$ (11,857)
Morphogen-LX
Schedule of Combined Deficit [Line Items]
Ordinary shares			13
Additional paid-in capital			364
Accumulated other comprehensive income (loss)			629
Accumulated deficit			(9,225)
Total combined deficit			(8,219)
Z Factor
Schedule of Combined Deficit [Line Items]
Ordinary shares			12
Additional paid-in capital			461
Accumulated other comprehensive income (loss)			139
Accumulated deficit			(8,568)
Total combined deficit			(7,956)
LockBody
Schedule of Combined Deficit [Line Items]
Ordinary shares			0
Additional paid-in capital			0
Accumulated other comprehensive income (loss)			(196)
Accumulated deficit			(6,052)
Total combined deficit			$ (6,248)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References + Details

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Debt (Details) $ in Thousands, £ in Millions		1 Months Ended		2 Months Ended	8 Months Ended	9 Months Ended
Debt (Details) $ in Thousands, £ in Millions	Jan. 29, 2021 shares	Nov. 30, 2020 GBP (£)	Jul. 31, 2019 GBP (£)	Mar. 31, 2021 USD ($) shares	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Conversion price, discount percentage, next qualified fundraising						20.00%
Conversion price, discount percentage, change in control						50.00%
Aggregate debt discounts					$ 700	$ 700
Forgiveness of convertible term loan				$ 6,199	$ 6,200
Series A Preferred \| Preferred Stock
Debt Instrument [Line Items]
Issuance of Series A convertible preferred shares upon conversion of debt (in shares) \| shares	568,181			568,181
Unsecured Convertible Term Notes Due June 2021 \| Convertible Notes Payable
Debt Instrument [Line Items]
Face amount							$ 5,000
Stated interest rate							8.00%
Convertible Term Notes Due August 2021
Debt Instrument [Line Items]
Proceeds from convertible debt \| £		£ 1.0	£ 3.0
Convertible Term Notes Due August 2021 \| Convertible Notes Payable
Debt Instrument [Line Items]
Face amount \| £			£ 5.0
Stated interest rate			2.00%

Commitments and Contingencies (Details) $ in Millions	Sep. 30, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Purchase obligation	$ 17.1
Purchase obligation, to be paid within one year	15.9
Purchase obligation, to be paid, year two and three	$ 1.2

Convertible Preferred Shares (Details) $ / shares in Units, $ in Thousands		1 Months Ended	2 Months Ended	8 Months Ended	9 Months Ended
	Jan. 29, 2021 USD ($) $ / shares shares	Jan. 29, 2021 USD ($) $ / shares	Mar. 31, 2021 shares	Sep. 30, 2021 USD ($) shares	Sep. 30, 2021 $ / shares shares	Sep. 30, 2020 USD ($)
Class of Stock [Line Items]
Ordinary shares, number of votes per share				1	1
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries (in shares)	4,450,000
Proceeds from the sale of Series A convertible preferred shares, net of issuance costs \| $		$ 0		$ 241,597		$ 0
Preferred Stock, dividends declared per share (in dollars per share) \| $ / shares					$ 0
Preferred stock, shares outstanding (in shares)				0	0
Convertible preferred stock, conversion ratio				1	1
Ordinary Shares
Class of Stock [Line Items]
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries (in shares)			4,450,000
Preferred Stock \| Series A Preferred
Class of Stock [Line Items]
Shares issued (in shares)	22,272,721		22,272,721
Shares issued, price per share (in dollars per share) \| $ / shares	$ 11.00	$ 11.00
Proceeds from the sale of Series A convertible preferred shares, net of issuance costs \| $	$ 245,000
Issuance of Series A convertible preferred shares upon conversion of debt (in shares)	568,181		568,181
Centessa Subsidiaries \| Replacement Equity Awards
Class of Stock [Line Items]
Share-based payment awards issued in period (in shares)	379,905
Centessa Subsidiaries \| Ordinary Shares
Class of Stock [Line Items]
Ordinary shares issued in connection with the acquisition (in shares)	45,137,984

Share-based Compensation - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		8 Months Ended	9 Months Ended
	Jan. 29, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 0	$ 4,133	$ 29	$ 10,093	$ 245
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	0	1,572	29	3,613	245
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 0	$ 2,561	$ 0	$ 6,480	$ 0

Share-based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions		8 Months Ended	9 Months Ended
	Jan. 29, 2021	Sep. 30, 2021	Sep. 30, 2021	May 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for equity incentive plan (in shares)				19,192,910
Shares available for grant (in shares)		8,437,705	8,437,705
Weighted-average grant date fair value of options granted (in dollars per share)		$ 7.47
Unrecognized compensation expense related to unvested stock option awards		$ 43.0	$ 43.0
Aggregate intrinsic value of options		101.9	101.9
Intrinsic value related to vested options		$ 7.0	$ 7.0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Contractual term			10 years
Unrecognized compensation expense recognition period		2 years 2 months 12 days
Share price (in dollars per share)		$ 16.70	$ 16.70
Restricted Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense recognition period		2 years 4 months 24 days
Share-based payment awards issued in period (in shares)	379,905
Unrecognized compensation expense excluding options		$ 15.6	$ 15.6
Restricted Share Awards \| Share-based Payment Arrangement, Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards issued in period (in shares)			833,897

Share-based Compensation - Summary of Stock Option Activity (Details)	8 Months Ended
	Sep. 30, 2021 $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	11,792,647
Exercised (in shares) \| shares	(50,000)
Forfeited (in shares) \| shares	(987,442)
Ending balance (in shares) \| shares	10,755,205
Exercisable at end of period (in shares) \| shares	574,267
Weighted-Average Exercise Price Per Share
Beginning balance (in dollars per share) \| $ / shares
Granted (in dollars per share) \| $ / shares	7.36
Exercised (in dollars per share) \| $ / shares	5.84
Forfeited (in dollars per share) \| $ / shares	6.29
Ending balance (in dollars per share) \| $ / shares	7.47
Exercisable at end of period (in dollars per share) \| $ / shares	$ 4.66
Weighted-Average Remaining Contractual Term
Options outstanding, weighted-average remaining contractual term	9 years 3 months 18 days
Options exercisable, weighted-average remaining contractual term	7 years 6 months

Share-based Compensation - Schedule of Assumptions Used to Estimate Fair Value of Stock Option Awards (Details) - Stock options	8 Months Ended
	Sep. 30, 2021 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 10 months 6 days
Expected stock price volatility	65.69%
Risk-free interest rate	0.85%
Expected dividend yield	0.00%
Estimated fair value of ordinary share (in dollars per share)	$ 7.47

Share-based Compensation - Summary of Replacement Equity Award Activity (Details) - Restricted Share Awards - $ / shares	8 Months Ended
	Sep. 30, 2021	Jan. 29, 2021
Number of Shares
Unvested beginning balance (in shares)	0
Granted (in shares)	1,213,802
Vested (in shares)	(226,441)
Unvested ending balance (in shares)	987,361
Weighted-Average Grant Date Fair Value Per Share
Unvested beginning balance (in dollars per share)	$ 17.80
Granted (in dollars per share)	15.57
Vested (in dollars per share)	5.84
Unvested ending balance (in dollars per share)	$ 17.80

Licensing Arrangements (Details) £ in Millions	1 Months Ended	3 Months Ended		8 Months Ended	9 Months Ended
Licensing Arrangements (Details) £ in Millions	Jan. 29, 2021 USD ($)	Sep. 30, 2021 USD ($) $ / £	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / £	Sep. 30, 2021 USD ($) $ / £	Sep. 30, 2021 GBP (£) $ / £	Mar. 31, 2019 USD ($) $ / £	Mar. 31, 2019 GBP (£) $ / £	Jan. 31, 2019 USD ($) $ / £	Jan. 31, 2019 GBP (£) $ / £	Dec. 31, 2015 USD ($) $ / £	Dec. 31, 2015 GBP (£) $ / £
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Foreign currency exchange rate, translation \| $ / £		0.74		0.74	0.74	0.74	0.86	0.86	0.74	0.74	0.74	0.74
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense		$ 0	$ 0	$ 0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Z Factor
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments											$ 500,000	£ 0.4
Research and development expense	$ 0	0	$ 0	0	$ 0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Morphogen-LX
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments											$ 1,100,000	£ 0.8
Research and development expense	$ 0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Palladio
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense				0
Maximum contingent consideration payment		32,500,000		32,500,000	32,500,000
Maximum aggregate commercial milestone payments		16,300,000		16,300,000	16,300,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Palladio \| Pfizer
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty payments		19,000,000		19,000,000	19,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| ApcinteX
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense				0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| ApcinteX \| CE
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments		900,000		900,000	900,000	£ 0.7
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Pega-One \| Roche
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments		16,000,000		16,000,000	16,000,000
Maximum aggregate commercial milestone payments		125,000,000		125,000,000	125,000,000
Upfront payment		2,000,000		2,000,000	$ 2,000,000
Minimum percent of consideration due to counterparty					10.00%
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Janpix Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and commercial milestone payments		30,000,000		30,000,000	$ 30,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Capella Biosciences Limited \| Lonza Sales AG
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense		42,060		116,960
Maximum aggregate development and commercial milestone payments		5,400,000		5,400,000	5,400,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| PearlRiver Bio GmbH \| LDC \| PearlRiver Bio GmbH License Agreement with Lead Discovery Center GmbH for Exon20
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments							$ 31,400,000	£ 27.0
Maximum aggregate commercial milestone payments							17,400,000	15.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| PearlRiver Bio GmbH \| LDC \| PearlRiver Bio GmbH License Agreement with Lead Discovery Center GmbH for C797
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments							9,100,000	7.8
Maximum aggregate commercial milestone payments							$ 11,600,000	£ 10.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia \| X-Chem
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments		24,800,000		24,800,000	24,800,000
Maximum aggregate commercial milestone payments		60,000,000		60,000,000	60,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia \| Heptares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments									$ 17,000,000	£ 12.6
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Inexia \| Heptares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments									$ 16,400,000	£ 12.1
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Inexia \| OptiNose
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and regulatory milestone payments		8,000,000		8,000,000	8,000,000
Maximum aggregate commercial milestone payments		$ 37,000,000		$ 37,000,000	$ 37,000,000

Related Party Transactions (Details) - USD ($)	1 Months Ended	3 Months Ended		8 Months Ended		9 Months Ended
Related Party Transactions (Details) - USD ($)	Jan. 29, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Related Party Transaction [Line Items]
Gain on extinguishment of debt	$ 0	$ 0	$ 72,000	$ 0	$ 0		$ 339,000
Affiliated Entity
Related Party Transaction [Line Items]
Related party interest expense	1,000	0	2,500		3,000		5,000
Affiliated Entity \| Support service agreement with Ultrahuman services
Related Party Transaction [Line Items]
Expenses from transactions with related party	48,000		200,000				600,000
Affiliated Entity \| Master services agreements with The Cambridge Partnership Limited
Related Party Transaction [Line Items]
Expenses from transactions with related party	17,000	39,000	29,000		200,000		77,000
Affiliated Entity \| Master services agreements with The Foundry (Cambridge) Limited
Related Party Transaction [Line Items]
Expenses from transactions with related party	4,000	10,000	12,000		31,000		34,000
Affiliated Entity \| Master services agreements with RxCelerate Limited
Related Party Transaction [Line Items]
Expenses from transactions with related party	400,000	1,900,000	800,000		5,200,000		2,500,000
Affiliated Entity \| Master services agreements with RxBiologics Limited
Related Party Transaction [Line Items]
Expenses from transactions with related party	14,000	100,000	40,000		300,000		67,000
Affiliated Entity \| Master services agreements with Cambridge Protein Works
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 0	$ 200,000	$ 57,000		300,000		$ 68,000
Investor
Related Party Transaction [Line Items]
Payments to shareholders as reimbursement					$ 1,400,000
Term Loan With Ultrahuman \| Affiliated Entity \| Centessa Predecessor Group
Related Party Transaction [Line Items]
Gain on extinguishment of debt						$ 264,000
Term Loan With Ultrahuman \| Affiliated Entity \| Bank of England Official Rate \| Centessa Predecessor Group
Related Party Transaction [Line Items]
Debt instrument, basis spread on variable rate						2.00%

Subsequent Events (Details) - Oberland Capital - Subsequent Event - USD ($)	Oct. 01, 2021	Oct. 31, 2021
Subsequent Event [Line Items]
Note purchase agreement, value	$ 300,000,000	$ 300,000,000
Revenue participation rate	1.00%
Net sales threshold	$ 200,000,000
Aggregate principal amount issued, percentage due	30.00%
Note repurchase, percentage of principal amount due, tranche one	175.00%
Note repurchase, percentage of principal amount due, tranche two	185.00%
Note repurchase, percentage of principal amount due, tranche three	205.00%
Note repurchase, maximum percentage of net proceeds due	0.75
Maximum
Subsequent Event [Line Items]
Revenue participation rate	2.67%
Senior Notes
Subsequent Event [Line Items]
Debt instrument, term	6 years
Debt instrument, reference rate	7.75%
Debt instrument, interest rate floor	8.00%
Stated interest rate	8.00%
Senior Notes \| London Interbank Offered Rate (LIBOR)
Subsequent Event [Line Items]
Debt instrument, basis spread on variable rate	0.25%
First Purchase Note
Subsequent Event [Line Items]
Note purchase agreement, value	$ 75,000,000
Second Purchase Note
Subsequent Event [Line Items]
Note purchase agreement, value	75,000,000
Third Purchase Note
Subsequent Event [Line Items]
Note purchase agreement, value	50,000,000
Fourth Purchase Notes
Subsequent Event [Line Items]
Note purchase agreement, value	$ 100,000,000