0001847903-22-000022 | 10-K | XBRL Viewer | Centessa Pharmaceuticals PLC

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Summary of Significant Accounting Policies - Foreign Currency Translation (Details) $ in Millions	11 Months Ended
	Dec. 31, 2021 USD ($)
Accounting Policies [Abstract]
Aggregate foreign currency transaction loss	$ 3.6

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation and Consolidation/Combination

References to the combined financial statements of the Centessa Predecessor Group refer to three of the eleven direct acquired 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 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 consolidated and combined financial statements include the Centessa Predecessor Group’s combined financial results for the twelve month periods ended December 31, 2020 and December 31, 2019, and the period from January 1, 2021 through January 29, 2021, and the Company’s consolidated financial results for the period from January 30, 2021 through December 31, 2021. The 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 December 31, 2021.

The accompanying 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 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 December 31, 2021 and the Predecessor’s financial position as of December 31, 2020;

•the Company’s results of operations and cash flows for the period from January 30, 2021 through December 31, 2021; and

•the Predecessor’s results of operations and cash flows for the period from January 1, 2021 through January 29, 2021 and for the twelve month periods ended December 31, 2020 and December 31, 2019.

The Company’s 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 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.

Emerging Growth Company

We are an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act (JOBS Act) enacted in April 2012. For so long as we remain an emerging growth company, we are permitted and intend to rely on certain exemptions from various public company reporting requirements, including not being required to have our internal control over financial reporting audited by our independent registered public accounting firm pursuant to Section 404(b) of the Sarbanes-Oxley Act of 2002, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and any golden parachute payments not previously approved.

We will remain an emerging growth company until the earlier to occur of (1) the last day of the fiscal year that is five years following the closing of our initial public offering, (2) the last day of the fiscal year in which we have total annual gross revenues of at least $1.07 billion, (3) the last day of the fiscal year in which we are deemed to be a “large accelerated filer,” under the rules of the U.S. Securities and Exchange Commission, or SEC, which means the market value of our equity securities that is held by non-affiliates exceeds $700 million as of the prior June 30th after we have been subject to the SEC’s periodic reporting requirements for at least twelve calendar months and have filed at least one annual report, and (4) the date on which we have issued more than $1.0 billion in non-convertible debt during the prior three-year period.

In addition, the JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. This provision allows an emerging growth company to delay the adoption of some accounting standards until those standards would otherwise apply to private companies. We are electing to utilize the extended transition period and, as a result, will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for emerging growth companies.

Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company” if the market value of our ordinary shares held by non-affiliates is below $250 million (or $700 million if our annual revenue is less than $100 million) as of June 30 in any given year, which would allow us to take advantage of many of the same exemptions from disclosure requirements, including reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements.

Cash and Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, certificate of deposits and money market funds.

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 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 monthly 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 consolidated and combined statements of operations and comprehensive loss within Other income (expense), net. The aggregate foreign currency transaction loss included in the Company (Successor)’s results of operations for the period from January 30, 2021 through December 31, 2021 was $3.6 million.

The functional currency of Centessa Pharmaceuticals plc had previously been British pounds (GBP), as Centessa Pharmaceutical plc’s primary activities during formation were mostly denominated in GBP, including related transaction costs, 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 in the second quarter of 2021, the functional currency of Centessa Pharmaceuticals plc changed from GBP to USD. The change in functional currency was 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 the number of 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 in 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 financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities

as of the date of the consolidated 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 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, the note purchase agreement, 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. 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 December 31, 2021, the Company’s property and equipment consisted largely of computer equipment, which is depreciated over its useful life of three years. Depreciation expense was $34 thousand for the period from January 30, 2021 through December 31, 2021.

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 December 31, 2021, the Company believes that no revision of the remaining useful lives or write-down of long-lived assets is required.

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 cash and cash equivalents, 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).

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 was based on the cumulative probability of achieving the specified milestone, which was 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. See Note 13 - "Subsequent Events".

Note Purchase Agreement

As described in further detail in Note 6 - "Debt", in October 2021, the Company entered into a Note Purchase Agreement (the “Notes”) 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. In addition to interest payments on the principal, the Company is obligated to pay certain revenue participation payments, 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; and is obligated to pay a one-time milestone payment upon the Company’s first product to obtain regulatory approval.

The Company evaluated the Notes and determined that the Notes include embedded derivatives that would otherwise require bifurcation as derivative liabilities. Neither the debt instrument nor any embedded features are required to be classified as equity. Therefore, the hybrid financial instrument comprised of the debt host and the embedded derivative liability may be accounted for under the fair value option. The Company elected to carry the Notes at fair value, and the debt instrument is outside the scope of ASC 480, Distinguishing Liabilities from Equity, and thus will be classified as a liability under ASC 470, Debt, in the Company’s financial statements. As the Company has elected to account for the Notes under the fair value option, debt issuance costs were immediately expensed.

The fair value of the Note Purchase Agreement represents the present value of estimated future payments, including interest, principal as well as estimated payments that are contingent upon the achievement of specified milestones. The fair value of the Notes is based on the cumulative probability of the various estimated payments. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestones, anticipated timelines, probability and timing of an early redemption of all obligations under the agreement and the discount rate. Any changes in the fair value of the liability in each reporting period are recognized in the consolidated statement of operations and comprehensive loss until it is settled.

Research and Development Expenses and Accruals

All research and development costs are expensed in the period incurred and consist primarily of salaries, payroll taxes, employee benefits, stock-based compensation charges for those individuals involved in research and development efforts, external research and development costs incurred under agreements with contract research organizations and consultants to conduct and support the Company’s ongoing clinical trials.

The Company has entered into various research and development contracts with clinical research organizations, clinical manufacturing organizations and other companies. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of costs incurred. Payments made in advance of performance are reflected in the accompanying balance sheets as prepaid expenses, while payments made after performance are reflected as accrued liabilities in the accompanying balance sheets. The Company records accruals for estimated costs incurred for ongoing research and development activities. When recording accruals for ongoing research and development activities, the Company analyzes progress of the services, including the phase or completion of events, invoices received and contracted costs. Nonrefundable advance payments for goods and services, including fees for process development or manufacturing and distribution of clinical supplies that will be used in future research and development activities, are recognized as expense in the period that the related goods are consumed or services are performed.

Milestone payments within the Company (Successor)’s licensing arrangements are recognized when achievement of the milestone is deemed probable to occur. To the extent products are commercialized and future economic benefit has been established, commercial milestones that become probable are capitalized and amortized over the estimated remaining useful life of the intellectual property. Significant judgments and estimates may be made in determining the prepaid or accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates.

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.

Collaborative Arrangements

The Company enters into collaborative arrangements to develop and commercialize intellectual property. These arrangements typically involve two (or more) parties who are active participants in the collaboration and are exposed to significant risks and rewards dependent on the commercial success of the activities. These collaborations usually involve various activities by one or more parties, including research and development, marketing and selling and distribution. Often, these collaborations require upfront, milestone and royalty or profit share payments, contingent upon the occurrence of certain future events linked to the success of the asset in development. Amounts due to collaborative partners related to development activities are generally reflected as research and development expense.

Share-Based Compensation

The Company and the Predecessor measure share-based awards, including restricted shares and stock options, at their grant-date fair value and record compensation expense on a straight-line basis over the vesting period of the awards. Subsequent to the IPO, the Company determines the fair value of share-based compensation awards using the market closing price of the Company’s ADSs on the date of grant. The Company accounts 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 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. The estimated annual dividend yield is 0% because the Company has not historically paid and does not expect for the foreseeable future to pay a dividend on its ordinary shares. Forfeitures of stock options are recognized in the period the forfeiture occurs.

Prior to its IPO in June 2021, the fair value of the Company’s ordinary shares was determined by the Company’s board of directors with assistance from management and an independent third-party valuation firm. As discussed in further detail in Note 3 - "Acquisition of Centessa Subsidiaries", the estimated fair value of its ordinary shares was based on the Hybrid Method 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”). 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. 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.

Retirement Plans

The Company provided defined contribution plans to its employees during 2021. In the US, the primary plan sponsored by the Company is a safe harbor, 401k plan with a 4% employer match, no waiting period and immediate vesting on the match. In the UK, the primary plan sponsored by the Company is a money purchase plan, which requires a minimum 7% contribution, including a minimum employer contribution of 3% and employee contribution of 4% in 2021. The Company recorded charges of $0.2 million under these plans during the period beginning January 30, 2021 to December 31, 2021.

Income Taxes

The Company follows the asset and liability method of accounting for income taxes under ASC 740, Income Taxes. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statements carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized.

ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense. There were no unrecognized tax benefits and no amounts accrued for interest and penalties as of December 31, 2021. The Company is currently not aware of any issues under review that could result in significant payments, accruals or material deviation from its position. The Company is subject to income tax examinations by major taxing authorities since inception.

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 period from January 30, 2021 through December 31, 2021, as they would be anti-dilutive.


Unvested ordinary shares			982,944
Stock options			11,730,382
			12,713,326

Recently Issued Accounting Pronouncements

In February 2016, the FASB issued ASU No. 2016-02, Leases (“ASC 842”), 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. Lessees and lessors must adopt ASC 842 utilizing a modified retrospective transition approach. Entities can elect to apply the transition requirements under ASC 842 either (a) at the beginning of the earliest period presented in the financial statements in the year of adoption or (b) in the period of adoption. 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. As of December 31, 2021, the Company was not party to any significant leases and therefore does not expect the adoption of this standard to have a significant impact as of the adoption date. This lease guidance will impact the Company’s consolidated financial statements and related disclosures when it is a party to such lease agreements. See Note 13 - "Subsequent Events".

In July 2021, the FASB issued ASU 2021-05, Lease (Topic): 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, Leases. 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. As of December 31, 2021, the Company was not a lessor in a lease agreement. Therefore, we do not

expect the adoption of this guidance to have any effect on the 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 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 Company), including interim periods within those fiscal years. The Company is currently evaluating the impact of ASU 2020-06 to the consolidated financial statements and related disclosures.

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 consolidated and combined financial statements.

Consolidated Statement of Shareholders' Equity (Parenthetical) $ in Millions	11 Months Ended
	Dec. 31, 2021 USD ($)
IPO
Debt issuance costs	$ 8.8
Series A preferred
Debt issuance costs	$ 3.4

Balance Sheet and Combined Deficit Components (Tables)

12 Months Ended

Dec. 31, 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 (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Research and development costs	$	11,224	$	992
Insurance related costs	4,661		9
Value added tax receivable	1,422		298
Other	993		6
	$	18,300	$	1,305

Schedule of Accrued Expenses and Other Current Liabilities

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


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Research and development costs	$	9,323	$	1,001
Personnel related expenses	4,865		—
Professional fees	1,514		37
Income tax liability	769		—
Other	102		9
	$	16,573	$	1,047

Schedule of Property and Equipment, Net

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


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Computer equipment	$	196	$	—
Less: Accumulated depreciation	(34)		—
Property and equipment, net	$	162	$	—

Schedule of Combined Deficit

Combined deficit of the Centessa Predecessor Group at January 29, 2021, December 31, 2020 and December 31, 2019 consisted of the following (amounts in thousands):


	Predecessor
	January 29, 2021		December 31, 2020		December 31, 2019
Morphogen-IX deficit
Ordinary shares	$	13	$	13	$	13
Additional paid-in capital	364		364		215
Accumulated other comprehensive income	636		629		589
Accumulated deficit	(9,413)		(9,225)		(5,590)
Total Morphogen-IX deficit	$	(8,400)	$	(8,219)	$	(4,773)
Z Factor deficit
Ordinary shares	$	12	$	12	$	11
Additional paid-in capital	461		461		274
Accumulated other comprehensive income	141		139		181
Accumulated deficit	(8,875)		(8,568)		(4,587)
Total Z Factor deficit	$	(8,261)	$	(7,956)	$	(4,121)
LockBody deficit
Ordinary shares	$	—	$	—	$	—
Additional paid-in capital	—		—		—
Accumulated other comprehensive income (loss)	(98)		(196)		41
Accumulated deficit	(6,386)		(6,052)		(3,004)
Total LockBody deficit	$	(6,484)	$	(6,248)	(2,963)
Total combined deficit	$	(23,145)	$	(22,423)	$	(11,857)

Summary of Significant Accounting Policies - Share-Based Compensation (Details)	11 Months Ended
	Dec. 31, 2021
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%

Income Taxes - Schedule of Components of Income Tax Provision (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Federal
Current			$ 581	$ 0
Deferred			(495)	0
State
Current			188	0
Deferred			(160)	0
Foreign
Current			0	0
Deferred			0	0
Income tax provision	$ 0	$ 114	$ 114	$ 0	$ 0

Income Taxes - Additional Information (Details) - USD ($) $ in Millions	11 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Jan. 29, 2021
Operating Loss Carryforwards [Line Items]
Valuation allowance increase	$ 30.5	$ 1.3
Deferred tax assets acquired			$ 16.1
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, subject to expiration	3.2
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, subject to expiration	$ 13.5

Consolidated and Combined Statements of Cash Flows - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (829)	$ (381,071)	$ (10,663)	$ (5,061)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired in-process research and development	0	220,454	0	0
Share-based compensation expense	0	14,851	336	236
Depreciation and amortization	0	34	0	6
Change in fair value of financial instruments	0	15,782	186	0
Changes in operating assets and liabilities:
Tax incentive receivable	74	(6,796)	(1,456)	(647)
Prepaid expenses and other assets	681	(16,164)	306	(1,397)
Accounts payable	(358)	4,157	(49)	855
Accrued expenses and other liabilities	(589)	12,968	653	123
Other, net	(28)	676	57	60
Net cash used in operating activities	(1,049)	(135,109)	(10,630)	(5,825)
Cash flows from investing activities:
Cash acquired upon acquisition of Centessa Subsidiaries	0	68,038	0	0
Cash paid to acquire in-process research and development	0	(4,596)	0	0
Purchase of property and equipment	0	(186)	0	0
Net cash provided by investing activities	0	63,256	0	0
Cash flows from financing activities:
Proceeds from the sale of convertible preferred shares, net of issuance costs	0	241,597	0	5,168
Proceeds from the sale of ordinary shares in connection with initial public offering, net of issuance costs paid in cash	0	344,136	0	0
Proceeds from issuance of debt, net of issuance costs	0	73,930	1,361	3,831
Repurchase of ordinary shares		(12)	0	0
Repayment of related party loan	0	(283)	0	0
Proceeds from option exercises	0	779	0	0
Other, net	0	0	1	6
Net cash provided by financing activities	0	660,147	1,362	9,005
Effect of exchange rate on cash and cash equivalents	80	1,822	(75)	520
Net increase (decrease) in cash and cash equivalents	(969)	590,116	(9,343)	3,700
Cash and cash equivalents at beginning of period	7,227	4,966	16,570	12,870
Cash and cash equivalents at end of period	6,258	595,082	7,227	16,570
Supplemental disclosure:
Interest paid	0	1,483	0	0
Non-cash investing and financing activities:
Issuance of ordinary shares upon acquisition of Centessa Subsidiaries	0	262,698	0	0
Issuance of contingent value rights upon acquisition of Centessa Subsidiaries	0	22,618	0	0
Issuance of Series A convertible preferred shares upon conversion of debt	0	6,250	0	0
Forgiveness of convertible term loan	0	6,199	0	0
Unpaid debt issuance costs at December 31, 2021	$ 0	$ 261	$ 0	$ 0

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Convertible term notes	$ 0	$ 5,339
Term loans	0	288
Long term debt	75,700	0
Current debt		$ 5,627
Note Purchase Agreement
Debt Instrument [Line Items]
Long-term debt, gross	$ 75,700

Summary of Significant Accounting Policies - Note Purchase Agreement (Details) - Oberland Capital - USD ($)	1 Months Ended
	Oct. 31, 2021	Oct. 04, 2021
Debt Instrument [Line Items]
Note purchase agreement, value	$ 300,000,000	$ 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
Senior Notes
Debt Instrument [Line Items]
Debt instrument, term	6 years
Senior Notes \| Interest Only, Senior Secured Notes
Debt Instrument [Line Items]
Debt instrument, term	6 years
Stated interest rate	8.00%

Balance Sheet and Combined Deficit Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development costs	$ 9,323	$ 1,001
Personnel related expenses	4,865	0
Professional fees	1,514	37
Income tax liability	769	0
Other	102	9
Accrued expenses and other current liabilities	$ 16,573	$ 1,047

Debt - Term Loans with Ultrahuman (Details) - Affiliated Entity - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Related party interest expense	$ 1	$ 3		$ 5
Term Loan With Ultrahuman
Short-term Debt [Line Items]
Gain on extinguishment of debt			$ 264
Term Loan With Ultrahuman \| Bank of England Official Rate
Short-term Debt [Line Items]
Debt instrument, basis spread on variable rate			2.00%

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments As of December 31, 2021, the Company had non-cancellable commitments for purchase of clinical materials, contract manufacturing, maintenance, and committed funding of up to $11.1 million, of which the Company expects to pay $10.9 million within one year and the remaining $0.2 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 is not a party to any litigation as of December 31, 2021, that, if determined adversely, would have a material adverse effect on its business and operations.

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	11 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Statutory tax rate benefit	19.00%	19.00%	19.00%
Non-deductible write-off of in-process R&D	(11.00%)	0.00%	0.00%
Other non-deductible expenses	(2.00%)	(1.00%)	(1.00%)
Enhanced research and development expenses	3.00%	15.00%	19.00%
Losses surrendered for tax incentive	(5.00%)	(28.00%)	(33.00%)
Non-taxable research and development incentive	2.00%	4.00%	5.00%
Change in tax rate	1.00%	1.00%	(1.00%)
Effect of overseas tax rates	1.00%	0.00%	0.00%
Change in valuation allowance	(8.00%)	(11.00%)	(8.00%)
Effective income tax rate	0.00%	0.00%	0.00%

Consolidated and Combined Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 595,082	$ 7,227
Tax incentive receivable	15,392	2,633
Prepaid expenses and other current assets	18,300	1,305
Total current assets	628,774	11,165
Property and equipment, net	162	0
Other non-current assets	699	552
Total assets	629,635	11,717
Current liabilities:
Accounts payable	8,065	1,032
Accrued expenses and other current liabilities	16,573	1,047
Convertible term notes	0	5,339
Term loans	0	288
Derivative liability	0	913
Total current liabilities	24,638	8,619
Long term debt	75,700	0
Contingent value rights	37,700	0
Other non-current liabilities	43	0
Total liabilities	138,081	8,619
Commitments and contingencies (Note 7)
Convertible preferred shares (£0.0001 nominal value): No shares authorized, issued and outstanding at December 31, 2021; 6,549,205 shares issued and outstanding at December 31, 2020	0	25,521
Shareholders’ equity and combined deficit:
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: 152,500,000 shares authorized; 89,988,228 shares issued and outstanding at December 31, 2021; No shares authorized, issued and outstanding at December 31, 2020	252
Additional paid-in capital	876,267
Accumulated other comprehensive income	688
Accumulated deficit	(385,653)
Combined deficit		(22,423)
Total shareholders' equity	491,554
Total combined deficit		(22,423)
Total liabilities, convertible preferred shares, shareholders’ equity and combined deficit	$ 629,635	$ 11,717

Acquisition of Centessa Subsidiaries (Tables)

12 Months Ended

Dec. 31, 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 (amounts 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

Related Party Disclosures (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Related Party Transactions

The Company and the Centessa Predecessor Group incurred research and development costs associated with these contracts as follows in the consolidated and combined statements of operations and comprehensive loss (amounts in thousands):


	Successor			Predecessor
		Period from January 30, 2021 through December 31, 2021		Period from January 1, 2021 through January 29, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Research and development		$	7,148	$	418	$	2,946	$	2,251

Consolidated and Combined Balance Sheets (Parenthetical) - £ / shares	Dec. 31, 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)	152,500,000	0
Common stock, shares issued (in shares)	89,988,228	0
Common Stock, shares outstanding (in shares)	89,988,228	0

Debt - Note Purchase Agreement (Details) - USD ($)		1 Months Ended	11 Months Ended	12 Months Ended
Debt - Note Purchase Agreement (Details) - USD ($)	Feb. 11, 2022	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 04, 2021
Debt Instrument [Line Items]
Milestone payment, percent of aggregate principal amount issued under the notes				30.00%
Milestone payment, period				5 years
Cumulative payments under note purchase agreement, including interest			$ 1,500,000	$ 1,500,000
Debt issuance expense		$ 0	$ 1,331,000		$ 0	$ 0
Lixivaptan
Debt Instrument [Line Items]
Revenue, Participation Rate				1.00%
Revenues				$ 200,000,000
Lixivaptan \| Maximum
Debt Instrument [Line Items]
Revenue, Participation Rate				2.67%
Subsequent Event
Debt Instrument [Line Items]
Note purchase agreement, value	$ 300,000,000
Note purchase agreement, amount available for funding at the option of the Company and Oberland Capital	$ 100,000,000
Debt instrument, term	6 years
Debt instrument, reference rate	7.75%
Debt instrument, interest rate floor	8.00%
Stated interest rate	8.00%
Note purchase agreement, percent of aggregate outstanding principal amount, cash balance required	75.00%
Note purchase agreement, deductible amount due to company	$ 100,000,000
Subsequent Event \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.25%
First Purchase Note
Debt Instrument [Line Items]
Note purchase agreement, value							$ 75,000,000
Second Purchase Note \| Subsequent Event
Debt Instrument [Line Items]
Note purchase agreement, value	$ 75,000,000
Third Purchase Note \| Subsequent Event
Debt Instrument [Line Items]
Note purchase agreement, value	$ 50,000,000
Note Purchase Agreement
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage of principal amount redeemed				75.00%
Debt issuance expense				$ 1,300,000
Note Purchase Agreement \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage				175.00%
Note Purchase Agreement \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage				185.00%
Note Purchase Agreement \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage				205.00%

Subsequent Events (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended	11 Months Ended	12 Months Ended
Subsequent Events (Details) - USD ($) $ in Thousands	Feb. 18, 2022	Jan. 29, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2020	Dec. 31, 2019	Feb. 07, 2022
Subsequent Event [Line Items]
Change in fair value of contingent value rights		$ 0		$ (15,082)		$ 0	$ 0
Forecast
Subsequent Event [Line Items]
Rent expense					$ 1,600
Rent expense, year 10					$ 1,900
Change in fair value of contingent value rights			$ 2,000
Subsequent Event
Subsequent Event [Line Items]
Office lease term								10 years
Subsequent Event \| Palladio \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Subsequent Event [Line Items]
Collaborative arrangement, rights and obligations, contingent value rights, amount	$ 39,700
Collaborative arrangement, rights and obligations, trading period	5 days
Collaborative arrangement, rights and obligations, shares issued as part of milestone payment (in shares)	3,938,423

Share-based Compensation - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 0	$ 14,852	$ 336	$ 236
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	0	5,896	336	236
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 0	$ 8,956	$ 0	$ 0

Share-based Compensation - Summary of Replacement Equity Award Activity (Details) - Restricted Share Awards - $ / shares	11 Months Ended
	Dec. 31, 2021	Jan. 29, 2021
Number of Shares
Unvested beginning balance (in shares)	0
Granted (in shares)	1,213,802
Vested (in shares)	(230,858)
Unvested ending balance (in shares)	982,944
Weighted-Average Grant Date Fair Value Per Share
Unvested beginning balance (in dollars per share)
Granted (in dollars per share)	15.57
Vested (in dollars per share)
Unvested ending balance (in dollars per share)

Consolidated and Combined Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating expenses:
Research and development	$ 662	$ 95,660	$ 9,301	$ 4,263
General and administrative	121	42,888	1,139	790
Change in fair value of contingent value rights	0	15,082	0	0
Acquired in-process research and development	0	220,454	0	0
Loss from operations	(783)	(374,084)	(10,440)	(5,053)
Interest (expense) income, net	(9)	(1,172)	(68)	5
Amortization of debt discount	(37)	0	(310)	(118)
Debt issuance costs	0	(1,331)	0	0
Other (expense) income, net	0	(4,370)	155	105
Loss before income taxes	(829)	(380,957)	(10,663)	(5,061)
Income tax expense	0	114	0	0
Net loss	(829)	(381,071)	(10,663)	(5,061)
Other comprehensive income (loss):
Foreign currency translation adjustment	107	778	(240)	412
Total comprehensive loss	$ (722)	$ (380,293)	$ (10,903)	$ (4,649)
Net loss per ordinary share - basic (in dollars per share)		$ (5.07)
Net loss per ordinary share - diluted (in dollars per share)		$ (5.07)
Weighted average ordinary shares outstanding - basic (in shares)		75,166,456
Weighted average ordinary shares outstanding - diluted (in shares)		75,166,456

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax asset
Tax loss carryforwards	$ 32,983	$ 2,323
Capitalized research and development	8,734	0
Research and development credits	6,967	0
Other	1,016	16
Total deferred tax asset	49,700	2,339
Valuation allowance	(49,045)	(2,339)
Deferred tax asset, net of allowance	$ 655	$ 0

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn February 7, 2022, the Company entered into a 10-year office lease for its new corporate headquarters in Boston, Massachusetts. The fixed annual rent will be approximately $1.6 million in 2023 and will escalate to approximately $1.9 million in Year 10. The company expects to have a right of use of the office space later in 2022.On February 18, 2022, the Company commenced dosing in its Phase 3 clinical trial evaluating lixivaptan as a potential treatment for ADPKD. Such event was the milestone trigger for payment of contingent value rights originally issued to the former shareholders and option holders of the Company’s subsidiary, Palladio Biosciences, Inc., in connection with its acquisition by Centessa in January 2021. The contingent value rights entitled such holders to a number of ordinary shares of the Company (including in the form of ADSs) in an aggregate amount of approximately $39.7 million based on the Volume Weighted Average Price of the Company’s ADSs over the five day trading period ending on the date of the milestone trigger. On March 8, 2022, the Company and the representative of the contingent value rights holders agreed that 3,938,423 represents the aggregate number of ordinary shares, issued as ADSs, to be issued in satisfaction of such contingent value rights, to the former shareholders and option holders of Palladio Biosciences, Inc. The number of ADSs issued to employee recipients reflected in this figure is net of tax withholding, which the Company satisfied with cash payments to tax authorities. The ADSs were issued in exchange for the previously-issued contingent value rights of the Company. The Company will recognize a remaining adjustment of fair value (approximately a $2 million charge) in its consolidated statement of operations and comprehensive loss in its first quarter of 2022.

Balance Sheet and Combined Deficit Components - Schedule of Combined Deficit (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 29, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Combined Deficit [Line Items]
Ordinary shares	$ 252
Additional paid-in capital	876,267
Accumulated other comprehensive income	688
Accumulated deficit	$ (385,653)
Total combined deficit		$ (23,145)	$ (22,423)	$ (11,857)	$ (7,450)
Morphogen-LX
Schedule of Combined Deficit [Line Items]
Ordinary shares		13	13	13
Additional paid-in capital		364	364	215
Accumulated other comprehensive income		636	629	589
Accumulated deficit		(9,413)	(9,225)	(5,590)
Total combined deficit		(8,400)	(8,219)	(4,773)
Z Factor
Schedule of Combined Deficit [Line Items]
Ordinary shares		12	12	11
Additional paid-in capital		461	461	274
Accumulated other comprehensive income		141	139	181
Accumulated deficit		(8,875)	(8,568)	(4,587)
Total combined deficit		(8,261)	(7,956)	(4,121)
LockBody
Schedule of Combined Deficit [Line Items]
Ordinary shares		0	0	0
Additional paid-in capital		0	0	0
Accumulated other comprehensive income		(98)	(196)	41
Accumulated deficit		(6,386)	(6,052)	(3,004)
Total combined deficit		$ (6,484)	$ (6,248)	$ (2,963)

- 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

Fair Value of Financial Instruments - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Quoted prices in active markets for identical assets (Level 1)
Liabilities
Note Purchase Agreement	$ 0
Contingent value rights	0
Derivative liability		$ 0
Significant other observable inputs (Level 2)
Liabilities
Note Purchase Agreement	0
Contingent value rights	0
Derivative liability		0
Significant unobservable inputs (Level 3)
Liabilities
Note Purchase Agreement	75,700
Contingent value rights	$ 37,700
Derivative liability		$ 913

Acquisition of Centessa Subsidiaries

12 Months Ended

Dec. 31, 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 (amounts 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 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 included 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 shares valued, in aggregate, at $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 Company determined that the CVR should be accounted for as a liability in accordance with ASC 480, Distinguishing Liabilities from Equity. 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 non-registrational safety study (designated the “ALERT Study”), an open-label study for which enrollment was on-going, the Company intended to commence the Phase 3 registrational study (designated the “ACTION Study”) in parallel with the ALERT Study. Therefore, the probability, at the date of acquisition of Centessa Subsidiaries, of commencing the ACTION Study and dosing the first patient was high and the milestone was 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. See Note 13 - "Subsequent Events".

Commitments and Contingencies (Details) $ in Millions	Dec. 31, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Purchase obligation	$ 11.1
Purchase obligation, to be paid within one year	10.9
Purchase obligation, to be paid, year two and three	$ 0.2

Share-based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Millions	11 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	12,872,147
Exercised (in shares) \| shares	(133,389)
Forfeited (in shares) \| shares	(1,008,376)
Ending balance (in shares) \| shares	11,730,382
Exercisable at end of period (in shares) \| shares	536,648
Vested and expected to vest at end of period (in shares) \| shares	11,730,382
Weighted-Average Exercise Price Per Share
Beginning balance (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	7.92
Exercised (in dollars per share) \| $ / shares	5.84
Forfeited (in dollars per share) \| $ / shares	6.41
Ending balance (in dollars per share) \| $ / shares	8.07
Exercisable at end of period (in dollars per share) \| $ / shares	4.82
Vested and expected to vest as end of period (in dollars per share) \| $ / shares	$ 8.07
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options outstanding, weighted-average remaining contractual term	9 years 2 months 12 days
Options outstanding, aggregate intrinsic value \| $	$ 46.4
Options exercisable, weighted-average remaining contractual term	7 years 9 months 18 days
Options exercisable, aggregate intrinsic value \| $	$ 3.7
Options vested and expected to vest, weighted-average remaining contractual term	9 years 2 months 12 days
Options vested and expected to vest, aggregate intrinsic value \| $	$ 46.4

Share-based Compensation

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Share-based Compensation

Centessa Pharmaceuticals plc (Successor) Stock Option and Incentive Plan

In January 2021, the Company’s board of directors approved the 2021 Stock Option and Incentive Plan (the “2021 Plan”). The 2021 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 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 20,026,816, of which 6,949,243 shares were available for future grants as of December 31, 2021. Beginning on January 1, 2022 and each January 1 thereafter, the number of Shares reserved and available for issuance under the 2021 Plan shall be cumulatively increased by 5% of the number of Shares issued and outstanding on the immediately preceding December 31, or such lesser number as the board of directors may determine.

Share-based Compensation Expense

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


	Successor			Predecessor
		Period from January 30, 2021 through December 31, 2021		Period from January 1, 2021 through January 29, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Research and development		$	5,896	$	—	$	336	$	236
General and administrative		8,956		—		—		—
		$	14,852	$	—	$	336	$	236

Centessa Pharmaceuticals plc (Successor) Stock Options

The following table summarizes stock option activity for the period from January 30, 2021 through December 31, 2021:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value (in million)
Balance at January 30, 2021	—	$	—
Granted	12,872,147	7.92
Exercised	(133,389)	5.84
Forfeited	(1,008,376)	6.41
Balance at December 31, 2021	11,730,382	$	8.07	9.2	$	46.4
Exercisable at December 31, 2021	536,648	$	4.82	7.8	$	3.7
Vested and expected to vest at December 31, 2021	11,730,382	$	8.07	9.2	$	46.4

The weighted-average grant date fair value of options granted was $5.03 per share for the period from January 30, 2021 through December 31, 2021. 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. As of December 31, 2021, the total unrecognized compensation expense related to unvested stock option awards was $48.6 million, which the Company expects to recognize over a weighted-average period of 2.2 years.

Based on the trading price of $11.26 per ADS, which was the closing price as of December 31, 2021, the aggregate intrinsic value of options as of December 31, 2021 was $46.4 million, of which $3.7 million was related to vested options.

During the period from January 30, 2021 through December 31, 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)	5.9
Expected stock price volatility	66.07	%
Risk-free interest rate	0.89	%
Expected dividend yield	- %

Centessa Pharmaceuticals plc (Successor) Restricted Share Awards

In connection with the acquisition of the Centessa Subsidiaries, the Company issued 379,905 ordinary shares subject to future vesting. For the period subsequent to the acquisition through December 31, 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. As of December 31, 2021, no shares have been issued.

The following table summarizes ordinary share activity for the period from January 30, 2021 through December 31, 2021:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
Unvested at January 30, 2021	—
Granted	1,213,802	$	15.57
Vested	(230,858)
Unvested at December 31, 2021	982,944

As of December 31, 2021, the total unrecognized compensation expense related to unvested ordinary shares was $14.5 million, which the Company expects to recognize over a weighted-average period of 2.2 years.

Centessa Predecessor Group Share-Based Plans

Prior to their acquisition in 2021, Z Factor and Morphogen-IX granted equity incentive shares, designated as B ordinary shares, to its employees, executives, and consultants and were purchased by the recipient for a nominal amount within one year from grant date. Generally, the awards vested 25% on the first anniversary of the grant date and ratably each quarter thereafter. Upon a change in control event or an initial public offering of the Z Factor and Morphogen-IX’s ordinary shares, the B ordinary shares converted, on a 1:1 basis, into ordinary shares. Z Factor and Morphogen-IX account for B ordinary shares as restricted shares for share-based compensation purposes as the purchase price was nominal.

Centessa Pharmaceuticals plc (Successor) 2021 Employee Share Purchase Plan

In January 2021, the Company’s board of directors approved the 2021 Employee Share Purchase Plan (the “2021 ESPP”). The initial number of shares reserved for issuance under the 2021 ESPP was 860,000. On January 1, 2022 and each January 1 thereafter, the number of Shares reserved and available for issuance under the ESPP shall be cumulatively increased by a number of shares equal to the lesser of: (i) 1% of the number of Shares issued and outstanding on the immediately preceding December 31; (ii) two times the initial number of shares reserved or (iii) such number of Shares as determined by the board of directors.

Balance Sheet and Combined Deficit Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development costs	$ 11,224	$ 992
Insurance related costs	4,661	9
Value added tax receivable	1,422	298
Other	993	6
Prepaid expenses and other current assets	$ 18,300	$ 1,305

Summary of Significant Accounting Policies - Segments (Details)	12 Months Ended
	Dec. 31, 2021 segment
Accounting Policies [Abstract]
Number of operating segments	1

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 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 that are measured at fair value on a recurring basis (amounts 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)
December 31, 2021 (Successor)
Liabilities
Note Purchase Agreement	$	—	$	—	$	75,700
Contingent Value Rights	$	—	$	—	$	37,700


	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		Note Purchase Agreement		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		75,000		—
Change in fair value	15,082		700		—
Balance at December 31, 2021 (Successor)	$	37,700	$	75,700	$	—

Fair Value of Financial Instruments - 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	11 Months Ended
	Jan. 29, 2021	Mar. 31, 2021	Dec. 31, 2021
Derivative Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 913	$ 0	$ 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	0
Additions		22,618
Change in fair value			15,082
Ending balance	0		37,700
Note Purchase Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance		0	0
Additions		$ 75,000
Change in fair value			700
Ending balance	$ 0		$ 75,700

Balance Sheet and Combined Deficit Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Less: Accumulated depreciation	$ (34)	$ 0
Property and equipment, net	162	0
Computer Equipment
Property, Plant and Equipment [Line Items]
Computer equipment	$ 196	$ 0

Debt - Centessa Pharmaceutical Limited Convertible Term Notes (Details) - USD ($) $ in Millions		11 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020
Series A preferred \| Preferred Stock
Short-term Debt [Line Items]
Issuance of Series A convertible preferred shares upon conversion of debt (in shares)	568,181	568,181
Unsecured Convertible Term Notes Due June 2021 \| Convertible Notes Payable
Short-term Debt [Line Items]
Face amount			$ 5.0
Stated interest rate			8.00%

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities were as follows (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Deferred tax asset
Tax loss carryforwards	$	32,983	$	2,323
Capitalized research and development	8,734		—
Research and development credits	6,967		—
Other	1,016		16
Total deferred tax asset	$	49,700	$	2,339
Valuation allowance	(49,045)		(2,339)
Deferred tax asset, net of allowance	$	655	$	—

Schedule of Components of Income Tax Provision

The income tax provision consists of the following (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Federal
Current	$	581	$	—
Deferred	(495)		—
State
Current	188		—
Deferred	(160)		—
Foreign
Current	—		—
Deferred	—		—
Income tax provision	$	114	$	—

Schedule of Effective Income Tax Rate Reconciliation

A reconciliation of the United Kingdom (“UK”) income tax rate to the Company’s effective tax rate is as follows:


	Successor		Predecessor
	Period from January 30, 2021 through December 31, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Statutory tax rate benefit	19	%	19	%	19	%
Non-deductible write-off of in-process R&D	(11)	%	—	%	—	%
Other non-deductible expenses	(2)	%	(1)	%	(1)	%
Enhanced research and development expenses	3	%	15	%	19	%
Losses surrendered for tax incentive	(5)	%	(28)	%	(33)	%
Non-taxable research and development incentive	2	%	4	%	5	%
Change in tax rate	1	%	1	%	(1)	%
Effect of overseas tax rates	1	%	—	%	—	%
Change in valuation allowance	(8)	%	(11)	%	(8)	%
Effective income tax rate	—	%	—	%	—	%

Summary of Operating Loss Carryforwards and Research Tax Credits

The following table summarizes carryforwards of federal and local net operating losses (NOL) and research tax credits (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
UK	$	82,156	$	12,393
US	$	34,059	$	—
France	$	19,710	$	—
Germany	$	11,062	$	—

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

Income Taxes - Summary of Operating Loss Carryforwards and Research Tax Credits (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
UK
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	$ 82,156	$ 12,393
US
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	34,059	0
France
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	19,710	0
Germany
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	$ 11,062	$ 0

Consolidated Statement of Shareholders' Equity - 11 months ended Dec. 31, 2021 - USD ($) $ in Thousands	Total	IPO	Over-Allotment Option	Series A preferred	Series A preferred Series A preferred	Ordinary shares	Ordinary shares IPO	Ordinary shares Over-Allotment Option	Additional paid-in capital	Additional paid-in capital IPO	Additional paid-in capital Over-Allotment Option	Accumulated other comprehensive income (loss)	Accumulated deficit
Beginning balance (in shares) at Jan. 29, 2021					0	7,500,000
Beginning balance at Jan. 29, 2021	$ (4,651)				$ 0	$ 21			$ 0			$ (90)	$ (4,582)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Sale of shares, net of issuance costs (in shares)					22,272,721		16,500,000	2,475,000
Sale of shares, net of issuance costs		$ 298,077	$ 46,059	$ 241,597	$ 241,597		$ 47	$ 7		$ 298,030	$ 46,052
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)
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
Stock option exercises (in shares)	133,389					133,389
Stock option exercises	$ 779								779
Share-based compensation expense	14,851								14,851
Vesting of ordinary shares (in shares)								230,858
Vesting of ordinary shares			$ 0					$ 1			$ (1)
Foreign currency translation adjustment	778											778
Net loss	(381,071)												(381,071)
Ending balance (in shares) at Dec. 31, 2021					0	89,988,228
Ending balance at Dec. 31, 2021	$ 491,554				$ 0	$ 252			$ 876,267			$ 688	$ (385,653)

Ordinary and Convertible Preferred Shares	12 Months Ended
Ordinary and Convertible Preferred Shares	Dec. 31, 2021
Equity [Abstract]
Ordinary and Convertible Preferred Shares	Ordinary and Convertible Preferred Shares Series A, Series B, and Seed Series 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 were 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 plc at the time of acquisition. Immediately following the acquisition, the Centessa Subsidiaries became wholly-owned subsidiaries of the Centessa Pharmaceuticals plc 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. Immediately prior to the closing of the initial public offering in June 2021, the outstanding Series A Preferred Shares were converted on a one-to-one basis into Ordinary Shares without payment or further consideration. The holders of Preferred Shares are entitled to dividends if and when declared by the Company’s board of directors. As of December 31, 2021, no dividends have been declared and no Preferred Shares were outstanding. 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. 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. 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.

Debt (Tables)

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Schedule of Debt


	(Amounts in thousands)
	Successor		Predecessor
	December 31, 2021		December 31, 2020
Note Purchase Agreement	$	75,700	$	—
Convertible Term Notes	—		5,339
Term Loans	—		288
	$	75,700	$	5,627

Fair Value of Financial Instruments - Additional Information (Details) $ in Thousands	11 Months Ended
	Dec. 31, 2021 USD ($)
Note Purchase Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in fair value	$ (700)

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

Income TaxesThe tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities were as follows (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Deferred tax asset
Tax loss carryforwards	$	32,983	$	2,323
Capitalized research and development	8,734		—
Research and development credits	6,967		—
Other	1,016		16
Total deferred tax asset	$	49,700	$	2,339
Valuation allowance	(49,045)		(2,339)
Deferred tax asset, net of allowance	$	655	$	—

The Company regularly assesses its ability to realize its deferred tax assets. Assessing the realization of deferred tax assets requires significant judgment. In determining whether its deferred tax assets are more likely than not realizable, the Company evaluated all available positive and negative evidence, and weighed the evidence based on its objectivity. After consideration of the evidence, including the Company's history of cumulative net losses in the U.K., France, Germany and the USA, the Company has concluded that it is more likely than not that the Company will not realize the benefits of its U.K., French and German deferred tax assets and accordingly the Company has provided a valuation allowance for the full amount of the net deferred tax assets in those territories. The Company has also concluded that it is more likely than not it will not realize the benefits of the deferred tax assets in its principal operating entity in the United States and has provided a valuation allowance for the full amount of the net deferred tax asset in that entity. The Company has considered the Company's history of cumulative net profits in two of its other operating entities in the United States, which carry out services for other entities in the group, estimated those entities' future taxable income and concluded that it is more likely than not that the Company will realize the benefits of the deferred tax assets in those entities, and has not provided a valuation allowance against the net deferred tax assets in those entities.

For the period from January 30, 2021 to December 31, 2021, the valuation allowance increased by $30.5 million. On January 29, 2021, the Company acquired $16.1 million in net deferred tax assets in its acquisitions of the Centessa Subsidiaries, primarily comprised of tax loss carryforwards and research and development tax credits. A full valuation allowance was recorded against these acquired deferred tax assets as it was concluded that it was not more likely than not that the Company would realize the benefits of the deferred tax assets, resulting in the remaining increase in total valuation allowance from December 31, 2020 to December 31, 2021. A full valuation allowance had been recorded against the Predecessor Group’s net deferred tax assets as of December 31, 2020. The valuation allowance increased by $1.3 million during the year ended December 31, 2020.

The income tax provision consists of the following (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Federal
Current	$	581	$	—
Deferred	(495)		—
State
Current	188		—
Deferred	(160)		—
Foreign
Current	—		—
Deferred	—		—
Income tax provision	$	114	$	—

A reconciliation of the United Kingdom (“UK”) income tax rate to the Company’s effective tax rate is as follows:


	Successor		Predecessor
	Period from January 30, 2021 through December 31, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Statutory tax rate benefit	19	%	19	%	19	%
Non-deductible write-off of in-process R&D	(11)	%	—	%	—	%
Other non-deductible expenses	(2)	%	(1)	%	(1)	%
Enhanced research and development expenses	3	%	15	%	19	%
Losses surrendered for tax incentive	(5)	%	(28)	%	(33)	%
Non-taxable research and development incentive	2	%	4	%	5	%
Change in tax rate	1	%	1	%	(1)	%
Effect of overseas tax rates	1	%	—	%	—	%
Change in valuation allowance	(8)	%	(11)	%	(8)	%
Effective income tax rate	—	%	—	%	—	%

The following table summarizes carryforwards of federal and local net operating losses (NOL) and research tax credits (amounts in thousands):


	Successor		Predecessor
	December 31, 2021		December 31, 2020
UK	$	82,156	$	12,393
US	$	34,059	$	—
France	$	19,710	$	—
Germany	$	11,062	$	—

The Company will recognize interest and penalties related to uncertain tax positions as a component of income tax expense. As of December 31, 2021, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company’s Consolidated Statements of Operations and Comprehensive Loss. Due to NOL and tax credit carry forwards that remain unutilized, income tax returns for tax years from 2019 and 2020 remain subject to examination by the taxing jurisdictions. The NOL carryforwards remain subject to review until utilized. The carryforwards in the UK, France and Germany do not expire, in the US, while the majority of Federal NOLs do not expire, certain Federal NOLs ($3.2 million) and all State NOLs ($13.5 million) expire beginning in 2036.

Section 382 of the Internal Revenue Code of 1986, as amended (the Code) provides for limitation on the use of net operating loss and research and development tax credit carryforwards following certain ownership changes (as defined in Code) that could limit the Company’s ability to utilize these carryforwards, in relation to its principal operating unit in the US. Pursuant to Section 382 of the Code, an ownership change occurs when the stock ownership of a 5% stockholder increases by more than 50% over a three-year testing period. The principal US operating unit may have experienced various ownership changes, as defined by the Code, as a result of past financings and may in the future experience an ownership change. Accordingly, the Company’s ability to utilize the aforementioned carryforwards may be limited. Additionally, U.S. tax laws limit the time during which these carryforwards may be applied against future taxes. The Company has not yet performed an Internal Revenue Code Section 382 study in connection with changes in control of its principal operating unit in the US.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Summary of Significant Accounting Policies - Retirement Plans (Details) - USD ($) $ in Millions	11 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021
Accounting Policies [Abstract]
Defined contribution plan, employer matching contribution, percent of match		4.00%
Defined contribution plan, minimum contribution, percent		7.00%
Defined contribution plan, minimum employer contribution, percent		3.00%
Defined contribution plan, minimum employee contribution, percent		4.00%
Defined contribution plan, charges	$ 0.2

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

The following fair value hierarchy table presents information about the Company’s assets and liabilities that are measured at fair value on a recurring basis (amounts 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)
December 31, 2021 (Successor)
Liabilities
Note Purchase Agreement	$	—	$	—	$	75,700
Contingent Value Rights	$	—	$	—	$	37,700


	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 fair value of the Note Purchase Agreement represents the present value of estimated future payments, including interest, principal as well as estimated payments that are contingent upon the achievement of specified milestones. The fair value of the notes is based on the cumulative probability of the various estimated payments. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestones, anticipated timelines, probability and timing of an early redemption of all obligations under the agreement and discount rate. Any changes in the fair value of the liability are recognized in the consolidated statement of operations and comprehensive loss until it is settled. For the period beginning on January 30, 2021 through December 31, 2021, the Company recorded a loss of $0.7 million for the estimated change in fair value of the Note Purchase Agreement, which was recorded in Other Income (Expense), net in the consolidated statement of operations and comprehensive loss.

The acquisition-date fair value of the contingent valuation rights liability represented the estimated future payments that are contingent upon the achievement of a specified development for Palladio’s product candidate. The fair value of the contingent value rights was based on the cumulative probability of achieving the specified milestone, which was expected by the first quarter of 2022. The fair value measurement at December 31, 2021 was 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 statement of operations and comprehensive loss until it is settled. See Note 13 - "Subsequent Events".

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 was marked-to-market each reporting period with the changes in fair value recorded in the consolidated and combined statements of operations and comprehensive loss until it was 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 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		Note Purchase Agreement		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		75,000		—
Change in fair value	15,082		700		—
Balance at December 31, 2021 (Successor)	$	37,700	$	75,700	$	—

- 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

Related Party Transactions - Additional Information (Details) $ in Millions	11 Months Ended
	Dec. 31, 2021 USD ($)
Investor
Related Party Transaction [Line Items]
Payments to shareholders as reimbursement	$ 1.4

Ordinary and Convertible Preferred Shares (Details) $ / shares in Units, $ in Thousands		1 Months Ended	11 Months Ended		12 Months Ended
	Jan. 29, 2021 USD ($) $ / shares shares	Jan. 29, 2021 USD ($) $ / shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2021 shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2021
Class of Stock [Line Items]
Ordinary shares, number of votes per share			1	1	1
Repurchase of ordinary shares concurrent with acquisition of Centessa Subsidiaries (in shares)	4,450,000
Proceeds from the sale of convertible preferred shares, net of issuance costs \| $		$ 0	$ 241,597			$ 0	$ 5,168
Convertible preferred stock, conversion ratio			1	1	1			1
Preferred Stock, dividends declared per share (in dollars per share) \| $ / shares					$ 0
Preferred stock, shares outstanding (in shares)			0	0	0
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 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

Acquisition of Centessa Subsidiaries - Additional Information (Details) - USD ($) $ in Thousands		1 Months Ended
	Jan. 29, 2021	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020
Asset Acquisition [Line Items]
Contingent value rights			$ 37,700	$ 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
Contingent value rights	$ 22,600	$ 22,600

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

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


Unvested ordinary shares			982,944
Stock options			11,730,382
			12,713,326

Related Party Transactions

12 Months Ended

Dec. 31, 2021

Related Party Transactions

Master Services agreements with drug discovery companies affiliated with David Grainger

The Centessa Predecessor Group entered into Master Services agreements with certain drug discovery companies affiliated with David Grainger, who was appointed as the Company’s Chief Innovation Officer in October 2021. These companies include RxCelerate Limited, RxBiologics Limited and The Foundry (Cambridge) Limited, of which David Grainger is a director and shareholder. The Company and the Centessa Predecessor Group incurred research and development costs associated with these contracts as follows in the consolidated and combined statements of operations and comprehensive loss (amounts in thousands):


	Successor			Predecessor
		Period from January 30, 2021 through December 31, 2021		Period from January 1, 2021 through January 29, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Research and development		$	7,148	$	418	$	2,946	$	2,251

Cost Reimbursements

During the period from January 30, 2021 through December 31, 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.

Debt

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Debt


	(Amounts in thousands)
	Successor		Predecessor
	December 31, 2021		December 31, 2020
Note Purchase Agreement	$	75,700	$	—
Convertible Term Notes	—		5,339
Term Loans	—		288
	$	75,700	$	5,627

Note Purchase Agreement

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, since amended on February 11, 2022, 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) a secured note in the aggregate principal amount of $75,000,000 (the “First Purchase Note”), which was funded on October 4, 2021, (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 December 31, 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.

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 1.0% (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”). As of December 31, 2021, the cumulative payments under the Note Purchase Agreement, including interest payments, totaled $1.5 million.

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 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.

On February 11, 2022, Centessa Pharmaceuticals plc, as issuer, and certain of the Company’s wholly owned subsidiaries, as guarantors (the “Guarantors”), entered into an Amendment to Note Purchase Agreement (the “Amendment”) with Three Peaks Capital Solutions Aggregator Fund (the “Purchaser”), and Cocoon SA LLC (the “Purchaser Agent”), an affiliate of Oberland Capital Management LLC, as agent for the Purchaser to modify the Note Purchase Agreement (the “Note Purchase Agreement”), dated as of October 1, 2021 by and among the Company, the Guarantors, the Purchaser and the Purchaser Agent.

Under the terms of the Amendment, the Company acknowledged the existence of certain Events of Default, including the delivery by the Company of a landlord consent after the required delivery date of October 31, 2021 and the entry by a subsidiary of the Company into a Research Collaboration and License Agreement without the prior consent of Purchaser Agent; as well as other non-financial, administrative-related defaults. Under the Note Purchase Agreement, Events of Default may entitle the lenders to default interest, penalties and the ability to terminate the facility and to accelerate repayment of any outstanding loans in full. Pursuant to the Amendment, the lenders agreed to waive such Events of Default.

Pursuant to the Amendment, the Purchaser and the Purchaser Agent have also agreed to waive the requirement to obtain the consent of a certain licensee and waive certain of the insurance requirements contained in the Note Purchase Agreement. The Amendment also provides that the Company is required to maintain a cash balance in an amount equal to 75% of the aggregate outstanding principal amount of all issued Notes, as defined in the Note Purchase Agreement, that have been issued on and from February 11, 2022. Also pursuant to the Amendment, the date for the Third Purchase Date, as defined in the Note Purchase Agreement, and the Commitment Termination Date were extended to December 31, 2023. The Amendment also provides that upon the sale of any of the Company’s or any of its subsidiary’s assets, if the Purchaser Agent elects to have the Company repurchase the notes, such repurchase amounts will be subject to a $100 million deductible such that the Purchaser Agent will not collect any repurchase amounts until $100 million has been received by the Company from such sale event. In addition, the reduced payment cap that is triggered by the Purchaser Agent opting into a repayment in the event of an asset sale, extends to the second loan tranche, if drawn. The effectiveness of the Amendment is subject to certain conditions precedent and conditions subsequent.

The Company evaluated the Notes under ASC 815, Derivatives and Hedging, and determined that the Notes include embedded derivatives that would otherwise require bifurcation as derivative liabilities. Neither the debt instrument nor any embedded features are required to be classified as equity. Therefore, the hybrid financial instrument comprised of the debt host and the embedded derivative liability may be accounted for under the fair value option. The Company has elected to carry the Notes at fair value, and the debt instrument is outside the scope of ASC 480, Distinguishing Liabilities from Equity, and thus will be classified as a liability under ASC 470, Debt, in the Company’s consolidated financial position. As the Company has elected to account for the Notes under the fair value option, debt issuance costs of $1.3 million were immediately expensed.

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 December 31, 2021.

Term loans with Ultrahuman

Prior to December 31, 2020, 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 had a stated interest rate of 2% per annum above the Bank of England official rate and the outstanding balances was repayable on demand of the lenders. The Bank of England official rate was 0.10% at December 31, 2020.

An 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 was recognized in the combined statements of operations and comprehensive loss for Centessa Predecessor Group during the twelve months ended December 31, 2020. During the twelve months ended December 31, 2020 and for the period from January 1, 2021 through January 29, 2021, the Centessa Predecessor Group recognized interest expense of $5,000, and $1,000, respectively, in connection with the Ultrahuman loans. During the period from January 30, 2021 through December 31, 2021, the Company recognized interest expense of $3,000, in connection with the loans. The loans were repaid in May 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Balance Sheet and Combined Deficit Components

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet and Combined Deficit Components

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


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Research and development costs	$	11,224	$	992
Insurance related costs	4,661		9
Value added tax receivable	1,422		298
Other	993		6
	$	18,300	$	1,305

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


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Research and development costs	$	9,323	$	1,001
Personnel related expenses	4,865		—
Professional fees	1,514		37
Income tax liability	769		—
Other	102		9
	$	16,573	$	1,047

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


	Successor		Predecessor
	December 31, 2021		December 31, 2020
Computer equipment	$	196	$	—
Less: Accumulated depreciation	(34)		—
Property and equipment, net	$	162	$	—

Combined deficit of the Centessa Predecessor Group at January 29, 2021, December 31, 2020 and December 31, 2019 consisted of the following (amounts in thousands):


	Predecessor
	January 29, 2021		December 31, 2020		December 31, 2019
Morphogen-IX deficit
Ordinary shares	$	13	$	13	$	13
Additional paid-in capital	364		364		215
Accumulated other comprehensive income	636		629		589
Accumulated deficit	(9,413)		(9,225)		(5,590)
Total Morphogen-IX deficit	$	(8,400)	$	(8,219)	$	(4,773)
Z Factor deficit
Ordinary shares	$	12	$	12	$	11
Additional paid-in capital	461		461		274
Accumulated other comprehensive income	141		139		181
Accumulated deficit	(8,875)		(8,568)		(4,587)
Total Z Factor deficit	$	(8,261)	$	(7,956)	$	(4,121)
LockBody deficit
Ordinary shares	$	—	$	—	$	—
Additional paid-in capital	—		—		—
Accumulated other comprehensive income (loss)	(98)		(196)		41
Accumulated deficit	(6,386)		(6,052)		(3,004)
Total LockBody deficit	$	(6,484)	$	(6,248)	(2,963)
Total combined deficit	$	(23,145)	$	(22,423)	$	(11,857)

Combined Statements of Convertible Preferred Shares and Combined Deficit - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
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)		6,549,205	0	6,549,205
Temporary equity, ending balance		$ 25,521	$ 0	$ 25,521
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Combined deficit, beginning balance	(22,423)		(23,145)	(11,857)	$ (7,450)
Sale of shares, net of issuance costs					0
Share-based compensation expense		336	14,851		236
Foreign currency translation adjustment	107	(240)	778	(240)	412
Net loss	(829)	(10,663)	(381,071)	(10,663)	(5,061)
Net equity contributions				1	6
Combined deficit, ending balance	$ (23,145)	$ (22,423)		$ (22,423)	$ (11,857)
Series A preferred
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Sale of shares, net of issuance costs			$ 241,597
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	3,670,620
Temporary equity, beginning balance	$ 13,329		$ 13,329	$ 13,329	$ 8,161
Temporary equity, Sale of Series A preferred shares (in shares)					666,662
Temporary equity, Sale of Series A preferred shares					$ 5,168
Temporary equity, ending balance (in shares)	4,337,282	4,337,282		4,337,282	4,337,282
Temporary equity, ending balance	$ 13,329	$ 13,329		$ 13,329	$ 13,329
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Sale of shares, net of issuance costs			$ 241,597
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
Temporary equity, beginning balance	$ 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
Temporary equity, ending balance	$ 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
Temporary equity, beginning balance	$ 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
Temporary equity, ending balance	$ 1,352	$ 1,352		$ 1,352	$ 1,352

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation and Consolidation/Combination	Basis of Presentation and Consolidation/Combination References to the combined financial statements of the Centessa Predecessor Group refer to three of the eleven direct acquired 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 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 consolidated and combined financial statements include the Centessa Predecessor Group’s combined financial results for the twelve month periods ended December 31, 2020 and December 31, 2019, and the period from January 1, 2021 through January 29, 2021, and the Company’s consolidated financial results for the period from January 30, 2021 through December 31, 2021. The 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 December 31, 2021. The accompanying 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 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 December 31, 2021 and the Predecessor’s financial position as of December 31, 2020; •the Company’s results of operations and cash flows for the period from January 30, 2021 through December 31, 2021; and •the Predecessor’s results of operations and cash flows for the period from January 1, 2021 through January 29, 2021 and for the twelve month periods ended December 31, 2020 and December 31, 2019. The Company’s 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 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.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, certificate of deposits and money market funds.
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 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 monthly 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 consolidated and combined statements of operations and comprehensive loss within Other income (expense), net. The aggregate foreign currency transaction loss included in the Company (Successor)’s results of operations for the period from January 30, 2021 through December 31, 2021 was $3.6 million. The functional currency of Centessa Pharmaceuticals plc had previously been British pounds (GBP), as Centessa Pharmaceutical plc’s primary activities during formation were mostly denominated in GBP, including related transaction costs, 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 in the second quarter of 2021, the functional currency of Centessa Pharmaceuticals plc changed from GBP to USD. The change in functional currency was 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 the number of 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 in 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 financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated 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 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, the note purchase agreement, 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. 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 December 31, 2021, the Company believes that no revision of the remaining useful lives or write-down of long-lived assets is required.
Fair Value Measurement	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 cash and cash equivalents, 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).
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 was based on the cumulative probability of achieving the specified milestone, which was 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.
Note Purchase Agreement	Note Purchase Agreement As described in further detail in Note 6 - "Debt", in October 2021, the Company entered into a Note Purchase Agreement (the “Notes”) 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. In addition to interest payments on the principal, the Company is obligated to pay certain revenue participation payments, 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; and is obligated to pay a one-time milestone payment upon the Company’s first product to obtain regulatory approval. The Company evaluated the Notes and determined that the Notes include embedded derivatives that would otherwise require bifurcation as derivative liabilities. Neither the debt instrument nor any embedded features are required to be classified as equity. Therefore, the hybrid financial instrument comprised of the debt host and the embedded derivative liability may be accounted for under the fair value option. The Company elected to carry the Notes at fair value, and the debt instrument is outside the scope of ASC 480, Distinguishing Liabilities from Equity, and thus will be classified as a liability under ASC 470, Debt, in the Company’s financial statements. As the Company has elected to account for the Notes under the fair value option, debt issuance costs were immediately expensed. The fair value of the Note Purchase Agreement represents the present value of estimated future payments, including interest, principal as well as estimated payments that are contingent upon the achievement of specified milestones. The fair value of the Notes is based on the cumulative probability of the various estimated payments. The fair value measurement is based on significant Level 3 unobservable inputs such as the probability of achieving the milestones, anticipated timelines, probability and timing of an early redemption of all obligations under the agreement and the discount rate. Any changes in the fair value of the liability in each reporting period are recognized in the consolidated statement of operations and comprehensive loss until it is settled.
Research and Development Expenses and Accruals	Research and Development Expenses and Accruals All research and development costs are expensed in the period incurred and consist primarily of salaries, payroll taxes, employee benefits, stock-based compensation charges for those individuals involved in research and development efforts, external research and development costs incurred under agreements with contract research organizations and consultants to conduct and support the Company’s ongoing clinical trials. The Company has entered into various research and development contracts with clinical research organizations, clinical manufacturing organizations and other companies. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of costs incurred. Payments made in advance of performance are reflected in the accompanying balance sheets as prepaid expenses, while payments made after performance are reflected as accrued liabilities in the accompanying balance sheets. The Company records accruals for estimated costs incurred for ongoing research and development activities. When recording accruals for ongoing research and development activities, the Company analyzes progress of the services, including the phase or completion of events, invoices received and contracted costs. Nonrefundable advance payments for goods and services, including fees for process development or manufacturing and distribution of clinical supplies that will be used in future research and development activities, are recognized as expense in the period that the related goods are consumed or services are performed. Milestone payments within the Company (Successor)’s licensing arrangements are recognized when achievement of the milestone is deemed probable to occur. To the extent products are commercialized and future economic benefit has been established, commercial milestones that become probable are capitalized and amortized over the estimated remaining useful life of the intellectual property. Significant judgments and estimates may be made in determining the prepaid or accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates.
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.
Collaborative Arrangement	Collaborative Arrangements The Company enters into collaborative arrangements to develop and commercialize intellectual property. These arrangements typically involve two (or more) parties who are active participants in the collaboration and are exposed to significant risks and rewards dependent on the commercial success of the activities. These collaborations usually involve various activities by one or more parties, including research and development, marketing and selling and distribution. Often, these collaborations require upfront, milestone and royalty or profit share payments, contingent upon the occurrence of certain future events linked to the success of the asset in development. Amounts due to collaborative partners related to development activities are generally reflected as research and development expense.
Share-Based Compensation	Share-Based Compensation The Company and the Predecessor measure share-based awards, including restricted shares and stock options, at their grant-date fair value and record compensation expense on a straight-line basis over the vesting period of the awards. Subsequent to the IPO, the Company determines the fair value of share-based compensation awards using the market closing price of the Company’s ADSs on the date of grant. The Company accounts 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 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. The estimated annual dividend yield is 0% because the Company has not historically paid and does not expect for the foreseeable future to pay a dividend on its ordinary shares. Forfeitures of stock options are recognized in the period the forfeiture occurs. Prior to its IPO in June 2021, the fair value of the Company’s ordinary shares was determined by the Company’s board of directors with assistance from management and an independent third-party valuation firm. As discussed in further detail in Note 3 - "Acquisition of Centessa Subsidiaries", the estimated fair value of its ordinary shares was based on the Hybrid Method 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”). 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. 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.
Retirement Plans	Retirement Plans The Company provided defined contribution plans to its employees during 2021. In the US, the primary plan sponsored by the Company is a safe harbor, 401k plan with a 4% employer match, no waiting period and immediate vesting on the match. In the UK, the primary plan sponsored by the Company is a money purchase plan, which requires a minimum 7% contribution, including a minimum employer contribution of 3% and employee contribution of 4% in 2021. The Company recorded charges of $0.2 million under these plans during the period beginning January 30, 2021 to December 31, 2021.
Income Taxes	Income Taxes The Company follows the asset and liability method of accounting for income taxes under ASC 740, Income Taxes. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statements carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense. There were no unrecognized tax benefits and no amounts accrued for interest and penalties as of December 31, 2021. The Company is currently not aware of any issues under review that could result in significant payments, accruals or material deviation from its position. The Company is subject to income tax examinations by major taxing authorities since inception.
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 February 2016, the FASB issued ASU No. 2016-02, Leases (“ASC 842”), 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. Lessees and lessors must adopt ASC 842 utilizing a modified retrospective transition approach. Entities can elect to apply the transition requirements under ASC 842 either (a) at the beginning of the earliest period presented in the financial statements in the year of adoption or (b) in the period of adoption. 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. As of December 31, 2021, the Company was not party to any significant leases and therefore does not expect the adoption of this standard to have a significant impact as of the adoption date. This lease guidance will impact the Company’s consolidated financial statements and related disclosures when it is a party to such lease agreements. See Note 13 - "Subsequent Events". In July 2021, the FASB issued ASU 2021-05, Lease (Topic): 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, Leases. 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. As of December 31, 2021, the Company was not a lessor in a lease agreement. Therefore, we do not expect the adoption of this guidance to have any effect on the 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 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 Company), including interim periods within those fiscal years. The Company is currently evaluating the impact of ASU 2020-06 to the consolidated financial statements and related disclosures. 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 consolidated and combined financial statements.

Debt - LockBody Therapeutics Ltd Convertible Term Notes (Details) $ in Thousands, £ in Millions	1 Months Ended		11 Months Ended	12 Months Ended
	Nov. 30, 2020 GBP (£)	Jul. 31, 2019 GBP (£)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Short-term Debt [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
Convertible Term Notes Due August 2021
Short-term Debt [Line Items]
Proceeds from convertible debt \| £	£ 1.0	£ 3.0
Convertible Term Notes Due August 2021 \| Convertible Notes Payable
Short-term Debt [Line Items]
Face amount \| £		£ 5.0
Stated interest rate		2.00%

Related Party Transactions - Summary of Related Party Transaction (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Master Service Agreements \| Affiliated Entity
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 418	$ 7,148	$ 2,946	$ 2,251

Share-based Compensation - Schedule of Assumptions Used to Estimate Fair Value of Stock Option Awards (Details) - Stock options	11 Months Ended
	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 10 months 24 days
Expected stock price volatility	66.07%
Risk-free interest rate	0.89%
Expected dividend yield	0.00%

Licensing Arrangements	12 Months Ended
Licensing Arrangements	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Licensing Arrangements	Licensing Arrangements The Company acquired almost all of the licensing arrangements below in connection with the acquisition of the Centessa Subsidiaries. As of December 31, 2021, the Company had no milestone obligations recorded on its balance sheet under these arrangements. Included in research and development expenses in the Company’s consolidated statement of operations and comprehensive loss for the period of January 30, 2021 to December 31, 2021 was aggregate incurred expenses of $1.7 million, reflecting the payment of a developmental milestone and the amortization of upfront costs. The Company does not expect payments related to these licensing arrangements over the next twelve months to be material to the Company’s consolidated financial statements. 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. Palladio has certain milestone obligations and certain royalty obligations arising in the event a Licensed Product is commercialized and the corresponding sales milestones are met. In relation to the purchase of the license, the Company is obligated to make certain contingent consideration payments to the seller. Such payments are structured as a tiered percentage of net sales with aggregate annual payment to the seller capped at $32.5 million. In addition, the Company is obligated to make sales-based milestones payments of up to $16.3 million and low single digit royalty payments (the first $19.0 million of which would be due to Pfizer). In the event Palladio sublicenses the ex-US rights to the Licensed Product to third parties, Palladio is further obligated to share any up-front payments and royalties it earns from such ex-US sublicenses, subject to certain caps. Certain other obligations arise if Palladio develops the Licensed Product for indications other than ADPKD. 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 is obligated to pay up to $40.0 million upon the achievement of development and regulatory milestones and up to $100.0 million in commercial milestones payments 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. The Company incurred research and development expenses of $1.0 million during the period January 30, 2021 to December 31, 2021. If Pega-One intends to enter into certain strategic transactions, either involving an acquisition or other change of control of Pega-One or the grant of rights by Pega-One to a third party, to develop and commercialize imgatuzumab or a Licensed Product in certain specified territories, Roche has an exclusive right of first negotiation to enter into the applicable strategic transaction with Pega-One. In connection with the Reorganization, Pega-One and Roche entered into a waiver, pursuant to which the parties acknowledged that the Reorganization would constitute a change of control transaction and Roche agreed not to exercise its right of first negotiation. Notwithstanding such waiver, Roche’s right of first negotiation would continue to apply for the period commencing on the completion of Centessa’s acquisition of Pega-One until the earlier of the third anniversary of such acquisition, or until the first change of control of Pega-One following such acquisition. Orexia Therapeutics Limited License and Collaborations Agreements The Company is a party to an exclusive worldwide license agreement with Heptares Therapeutics Limited (“Heptares”), to further develop and commercialize, the licensed technology for orexin agonist as well as the intranasal orexin antagonist. The Company is responsible for supplying all active pharmaceutical ingredients and finished drug product for exploitation. The Company is obligated to make up to $33.4 million (£24.7 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 Centessa sublicenses the approved technology. In addition, the Company is obligated to fund any development related costs associated with the licensed technology. 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. In October 2021, the agreement was amended to change the financial terms, reducing the milestones and royalty obligations for nominal consideration. After the amendment, Orexia is obligated to make up to $3 million in payments upon the achievement of development and regulatory milestones and $5 million upon the achievement of a commercial milestone. In October 2021, the Company entered into a license agreement with Schrodinger to utilize its computational platform, which facilitates high-performance calculations for drug discovery to enable accurate prediction of potency at the target of interest. The collaboration will be enabled by Orexia’s structural biology capabilities, including the stabilized OX2R protein exclusively licensed from Heptares, and high-resolution crystal structures in agonist conformation. Under the terms of the agreement, Orexia will be responsible for preclinical research activities, clinical development and commercialization of future product candidates discovered under the collaboration. Schrödinger received an upfront nonrefundable software access payment and may become eligible to receive certain development and regulatory milestones up to $35.0 million as well as commercial milestone payments up to $80.0 million, as well as low single digit royalties on global net sales. The Company incurred approximately $0.7 million in research and development expense related to the license agreement during the period from January 30, 2021 through December 31, 2021. The Company is a party to a license agreement with OptiNose AS (“OptiNose”), whereby the Company 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. The Company is solely responsible for all costs and activities related to its identification, development, and commercialization of products under the license agreement. The Company 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. PearlRiver License and Collaboration Agreements 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. Additionally, In June 2020, PearlRiver Bio entered to an assignment agreement with Lead Discovery Center GmbH and TU Dortmund (together the “Assignors”), involving small molecule inhibitors of C797 mutated EGFR and related inventions (C797, or Product). Under the assignment agreement, the Assignors each and jointly sold, assigned and transferred to PearlRiver Bio their entire right, title and interest to certain know-how, patent application, invention disclosures, chemical and biological materials, and data analyses related to C797. PearlRiver is responsible for supplying all active pharmaceutical ingredients and finished drug products for exploitation. PearlRiver is obligated to make up to $39.5 million (€34.8 million at an exchange rate of 0.88) in payments upon the achievement of development and regulatory milestones and $28.4 million (€25.0 million at an exchange rate of 0.88) 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. Janpix Limited License Agreement In July 2017, Janpix Limited (“Janpix”) entered into a license agreement with the Governing Council of the University of Toronto (“UT”) related to direct small molecule modulators of signal transducer and activator of transcription 3 (“STAT 3”) and signal transducer and activator of transcription 5 (“STAT 5”). Under the license agreement, Janpix obtained an exclusive, worldwide, sublicensable (subject to certain conditions) license, under certain patents and know-how (“Licensed Technology”), to research, develop, manufacture, market, sell, distribute and commercially exploit any licensed products for all uses in humans and animals (the “Field”). UT has retained for itself and certain other institutions, a customary right of use to the Licensed Technology for academic research and educational purposes. Additionally, Janpix has the right to exclusively license, with the right to sublicense, certain improvements to the Licensed Technology under the license agreement. Janpix also has an option right to negotiate a new license grant to any other intellectual property related to STAT 3 and/or STAT 5 inhibitors that is not considered an improvement under the license agreement. Janpix is obligated to make up to $15.0 million in development milestone payments and $15.0 million in 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. Other License and Collaboration Agreements The Company is a party to other license and collaboration agreements to develop and commercialize intellectual property in addition to the agreements discussed above. In aggregate, Centessa is obligated to make up to $2.5 million in development milestone payments related to these other agreements.

Share-based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions			1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 01, 2022	Jan. 29, 2021 shares	Jan. 29, 2021	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	May 31, 2021 shares	Jan. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for equity incentive plan (in shares)						20,026,816
Shares available for grant (in shares)				6,949,243	6,949,243
Percent of additional shares authorized each year					5.00%
Weighted-average grant date fair value of options granted (in dollars per share) \| $ / shares				$ 5.03
Unrecognized compensation expense related to unvested stock option awards \| $				$ 48.6	$ 48.6
Aggregate intrinsic value of options \| $				46.4	46.4
Intrinsic value related to vested options \| $				$ 3.7	$ 3.7
Share-based compensation, award vesting rights, percentage			25.00%
Common stock, conversion ratio		1	1
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) \| $ / shares				$ 11.26	$ 11.26
Restricted Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense recognition period				2 years 2 months 12 days
Share-based payment awards issued in period (in shares)		379,905		0
Unrecognized compensation expense excluding options \| $				$ 14.5	$ 14.5
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
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares reserved for future issuance (in shares)							860,000
Employee Stock \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, percentage of outstanding stock maximum	1.00%
Multiplier for initial number of shares reserved	2

Licensing Arrangements (Details) £ in Millions	11 Months Ended
Licensing Arrangements (Details) £ in Millions	Dec. 31, 2021 USD ($) $ / £	Dec. 31, 2021 GBP (£) $ / £	Oct. 31, 2021 USD ($)	Mar. 31, 2019 USD ($) $ / £	Mar. 31, 2019 GBP (£) $ / £	Jul. 31, 2017 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Foreign currency exchange rate, translation \| $ / £	0.74	0.74		0.88	0.88
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate development and commercial milestone payments	$ 0
Collaborative arrangement, research and development expense	1,700,000
Maximum aggregate development and regulatory milestone payments	2,500,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Palladio
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum contingent consideration payment	32,500,000
Maximum aggregate commercial milestone payments	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
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Pega-One \| Roche
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expense	1,000,000
Maximum aggregate commercial milestone payments	100,000,000
Maximum aggregate development and regulatory milestone payments	40,000,000
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	33,400,000	£ 24.7
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia \| X-Chem
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate commercial milestone payments	5,000,000
Maximum aggregate development and regulatory milestone payments	3,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia \| Schrodinger
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expense	700,000
Maximum aggregate commercial milestone payments			$ 80,000,000
Maximum aggregate development and regulatory milestone payments			$ 35,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia \| OptiNose
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate commercial milestone payments	37,000,000
Maximum aggregate development and regulatory milestone payments	$ 8,000,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| PearlRiver Bio GmbH \| LDC
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate commercial milestone payments				$ 28,400,000	£ 25.0
Maximum aggregate development and regulatory milestone payments				$ 39,500,000	£ 34.8
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Janpix Limited \| Governing Council of UT
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum aggregate commercial milestone payments						$ 15,000,000
Maximum aggregate development and regulatory milestone payments						$ 15,000,000

Summary of Significant Accounting Policies - Property and Equipment, net (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 29, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 0	$ 34		$ 0	$ 6
Computer Equipment
Property, Plant and Equipment [Line Items]
Property and equipment useful life			3 years

Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of Share-based Compensation Expense


	Successor			Predecessor
		Period from January 30, 2021 through December 31, 2021		Period from January 1, 2021 through January 29, 2021		Twelve Months Ended December 31, 2020		Twelve Months Ended December 31, 2019
Research and development		$	5,896	$	—	$	336	$	236
General and administrative		8,956		—		—		—
		$	14,852	$	—	$	336	$	236

Summary of Stock Option Activity

The following table summarizes stock option activity for the period from January 30, 2021 through December 31, 2021:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value (in million)
Balance at January 30, 2021	—	$	—
Granted	12,872,147	7.92
Exercised	(133,389)	5.84
Forfeited	(1,008,376)	6.41
Balance at December 31, 2021	11,730,382	$	8.07	9.2	$	46.4
Exercisable at December 31, 2021	536,648	$	4.82	7.8	$	3.7
Vested and expected to vest at December 31, 2021	11,730,382	$	8.07	9.2	$	46.4

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

During the period from January 30, 2021 through December 31, 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)	5.9
Expected stock price volatility	66.07	%
Risk-free interest rate	0.89	%
Expected dividend yield	- %

Summary of Replacement Equity Award Activity

The following table summarizes ordinary share activity for the period from January 30, 2021 through December 31, 2021:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
Unvested at January 30, 2021	—
Granted	1,213,802	$	15.57
Vested	(230,858)
Unvested at December 31, 2021	982,944

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

Organization and Description of Business (Details)	1 Months Ended		12 Months Ended
Organization and Description of Business (Details)	Oct. 31, 2021 USD ($)	Jun. 30, 2021 USD ($) shares	Dec. 31, 2021 USD ($)	Dec. 31, 2021 £ / shares	Oct. 04, 2021 USD ($)	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			$ 385,653,000
Cash and cash equivalents			$ 595,082,000					$ 7,227,000
Sufficient funding term (at least)			12 months
Oberland Capital
Subsidiary, Sale of Stock [Line Items]
Note purchase agreement, value	$ 300,000,000				$ 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
Oberland Capital \| Senior Notes
Subsidiary, Sale of Stock [Line Items]
Debt instrument, term	6 years
Oberland Capital \| 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 - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-Average Ordinary Shares Outstanding (Details)	11 Months Ended
	Dec. 31, 2021 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)	12,713,326
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)	982,944
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)	11,730,382

Organization and Description of Business	12 Months Ended
Organization and Description of Business	Dec. 31, 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 clinical-stage pharmaceutical company with a Research & Development (“R&D”) innovation engine that aims to discover, develop and ultimately deliver impactful medicines to patients. 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 historical financial statements of the Group for periods prior to January 30, 2021 are presented on a combined basis and are denoted as “Predecessor” within these 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 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 Depositary 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 early 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. The Group and the Company have incurred losses and negative cash flows from operations since inception and the Company had an accumulated deficit of $385.7 million as of December 31, 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 6 "Debt"). The Company expects its existing cash and cash equivalents as of December 31, 2021 of $595.1 million 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 consolidated financial statements. Global Pandemic – COVID-19 On March 10, 2020, the WHO 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 December 31, 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.