0001847903-23-000155 | 10-Q | XBRL Viewer | Centessa Pharmaceuticals PLC

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Fair Value Measurement - Schedule of Fair Value, Financial Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
U.S. Treasury securities
Assets
U.S. Treasury securities	$ 158,367
Quoted prices in active markets for identical assets (Level 1) \| Fair Value, Recurring
Liabilities
Note Purchase Agreement	0	$ 0
Quoted prices in active markets for identical assets (Level 1) \| Fair Value, Recurring \| U.S. Treasury securities
Assets
U.S. Treasury securities	158,367
Quoted prices in active markets for identical assets (Level 1) \| Fair Value, Recurring \| Money Market fund
Assets
Money Market fund	33,889
Significant other observable inputs (Level 2) \| Fair Value, Recurring
Liabilities
Note Purchase Agreement	0	0
Significant other observable inputs (Level 2) \| Fair Value, Recurring \| U.S. Treasury securities
Assets
U.S. Treasury securities	0
Significant other observable inputs (Level 2) \| Fair Value, Recurring \| Money Market fund
Assets
Money Market fund	0
Significant unobservable inputs (Level 3) \| Fair Value, Recurring
Liabilities
Note Purchase Agreement	73,300	$ 69,800
Significant unobservable inputs (Level 3) \| Fair Value, Recurring \| U.S. Treasury securities
Assets
U.S. Treasury securities	0
Significant unobservable inputs (Level 3) \| Fair Value, Recurring \| Money Market fund
Assets
Money Market fund	$ 0

Share-based Compensation

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Share-based Compensation

Centessa Pharmaceuticals plc 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, restricted stock units 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. 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. Remaining shares available for future grants as of June 30, 2023 were 8,284,827.

Share-based Compensation Expense

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


	Three Months Ended June 30, 2023		Three Months Ended June 30, 2022		Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Research and development	$	3,255	$	2,654	$	6,539	$	5,487
General and administrative	3,958		2,949		7,864		5,834
	$	7,213	$	5,603	$	14,403	$	11,321

Stock Options

The following table summarizes stock option activity for the six months ended June 30, 2023:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term
Balance at January 1, 2023	14,688,996	$	7.88	8.5 years
Granted	2,818,300	$	4.13
Exercised	(3,776)	$	3.85
Forfeited	(1,456,693)	$	8.39
Balance at June 30, 2023	16,046,827	$	7.18	8.2 years
Exercisable at June 30, 2023	6,858,127	$	7.61	7.6 years
Vested and expected to vest at June 30, 2023	16,046,827	$	7.18	8.2 years

The weighted-average grant date fair value of options granted was $2.87 per share for the six months ended June 30, 2023. As of June 30, 2023, the total unrecognized compensation expense related to unvested stock option awards was $38.5 million, which the Company expects to recognize over a weighted-average period of 2.3 years.

Based on the trading price of $6.19 per ADS, which is the closing price as of June 30, 2023, the aggregate intrinsic value of options as of June 30, 2023 was $9.9 million.

During the six months ended June 30, 2023, the fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below:


Expected term	6.0 years
Expected stock price volatility	77.9	%
Risk-free interest rate	3.6	%
Expected dividend yield	0	%

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. Forfeitures of stock options are recognized in the period the forfeiture occurs.

Restricted Share Awards and Units

In connection with the acquisition of the Centessa subsidiaries in January 2021, the Company issued 379,905 ordinary shares subject to future vesting under its Restricted Stock Awards program. For the period subsequent to the acquisition, the Company issued an additional 833,897 ordinary shares subject to future vesting to an employee. The fair value of the awards were based upon the estimated fair value of the Company’s ordinary shares at the time of grant.

The Board, following the recommendations of the Company’s Compensation Committee, grants service-based restricted stock unit awards under the Company’s Stock Incentive Plan to certain executive officers and employees of the Company to encourage employee retention. Periodic grants are made at fair market value, representing the NASDAQ market close quoted price on the day of the grant.

The following table summarizes ordinary share activity related to the restricted stock programs for the six months ended June 30, 2023:


	Restricted Stock Awards			Restricted Stock Units
	Number of Shares		Weighted-Average Grant Date Fair Value Per Share	Number of Shares		Weighted-Average Grant Date Fair Value Per Share
Unvested at January 1, 2023	599,421			1,804,760
Granted	—		n/a	1,427,225		$	3.85
Vested	(175,806)			(440,924)
Forfeited	—			(320,807)
Unvested at June 30, 2023	423,615			2,470,254

Unrecognized compensation expense at June 30, 2023 (in thousands)	$	7,940		$	10,463
Expected weighted average recognition period	1.8 years			2.4 years

Employee Share Purchase Plan

In January 2021, the Company’s board of directors approved the 2021 Employee Share Purchase Plan (the “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. As of June 30, 2023, no shares have been purchased or issued under the ESPP and remaining shares reserved for the ESPP were 2,708,315.

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (75,600)	$ (119,159)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	14,403	11,321
Depreciation and amortization	326	60
Change in fair value of financial instruments	3,500	(6,320)
Change in deferred taxes	(23,490)	52
Changes in operating assets and liabilities:
Tax incentive receivable	(1,835)	(5,300)
Prepaid expenses and other assets	(731)	872
Operating leases, net	(2,094)	0
Accounts payable	(3,391)	623
Accrued expenses and other liabilities	(2,988)	7,957
Net cash used in operating activities	(91,900)	(109,894)
Cash flows from investing activities:
Purchases of investments in marketable securities	(157,337)	0
Purchases of property and equipment	(98)	(469)
Net cash used in investing activities	(157,435)	(469)
Cash flows from financing activities:
Proceeds from option exercises	12	405
Other, net	0	(261)
Net cash provided by financing activities	12	144
Effect of exchange rate on cash and cash equivalents	899	(702)
Net decrease in cash and cash equivalents	(248,424)	(110,921)
Cash and cash equivalents at beginning of period	393,644	595,082
Cash and cash equivalents at end of period	145,220	484,161
Supplemental disclosure:
Interest paid	4,795	3,153
Income taxes paid	2,706	862
Operating lease payments reducing operating lease liabilities	393	0
ROU assets obtained in exchange for operating lease liabilities	9,711	0
Non-cash investing and financing activities:
Issuance of ordinary shares to settle outstanding contingent value rights	$ 0	$ 39,680

Commitments and Contingencies - Cash Flow, Supplemental Disclosures (Details)	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Weighted-average remaining lease term	9 years 7 months 6 days
Weighted-average discount rate	11.97%

Fair Value Measurement - Schedule of Debt Securities, Fair Value of U.S. Treasury Securities and Money Market Fund (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Money Market fund, included in Cash and cash equivalents, amortized cost	$ 145,220	$ 393,644
Money Market fund
Debt Securities, Available-for-Sale [Line Items]
Money Market fund, included in Cash and cash equivalents, amortized cost	33,889
Money Market fund, included in Cash and cash equivalents, fair value	33,889
U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
U.S. Treasury securities, amortized cost	157,337
U.S. Treasury securities, gross unrealized gains	1,036
U.S. Treasury securities, gross unrealized losses	(6)
U.S. Treasury securities, fair value	158,367
U.S. Treasury securities \| Short-term investments
Debt Securities, Available-for-Sale [Line Items]
U.S. Treasury securities, amortized cost	157,337
U.S. Treasury securities, gross unrealized gains	1,036
U.S. Treasury securities, gross unrealized losses	(6)
U.S. Treasury securities, fair value	$ 158,367

Balance Sheet Components - Components of Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 1,430	$ 1,332
Less: Accumulated depreciation	(285)	(164)
Property and equipment, net	1,145	1,168
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	706	442
Office furniture
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	724	0
Other, primarily construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 0	$ 890

Income Taxes	6 Months Ended
Income Taxes	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income TaxesThe Company recorded an income tax benefit of $24.1 million for the three months ended June 30, 2023 compared with an income tax benefit of $22.0 thousand for the three months ended June 30, 2022. The higher income tax benefit in the second quarter of 2023 was a result of the release of a valuation allowance as a result of an internal reorganization of its subsidiaries that occurred in the quarter. 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, the Company believes it would more likely than not be able to utilize existing loss carryforwards and research and development tax credits to offset future income in the United States. The operating entity in the United States has a history of cumulative net profits as it carries out services for other entities in the group.

- 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.

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+ Details

Debt (Tables)

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Schedule of Debt

Debt as of June 30, 2023 and December 31, 2022 (in thousands):


	June 30, 2023		December 31, 2022
Note Purchase Agreement	$	73,300	$	69,800

Balance Sheet Components

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

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


	June 30, 2023		December 31, 2022
Research and development expenses	$	12,830	$	11,321
Insurance related expenses	1,704		2,788
Value added tax receivable	1,272		2,557
Other	3,869		3,271
	$	19,675	$	19,937

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


	June 30, 2023		December 31, 2022
Research and development expenses	$	15,147	$	10,795
Personnel related expenses	4,510		7,264
Professional fees	2,158		4,171
Income tax liability	—		1,582
Operating lease liabilities	460		—
Other	507		690
	$	22,782	$	24,502

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


	June 30, 2023		December 31, 2022
Computer equipment	$	706	$	442
Office furniture	724		—
Other, primarily construction in progress	—		890
Property and equipment, at cost	1,430		1,332
Less: Accumulated depreciation	(285)		(164)
Property and equipment, net	$	1,145	$	1,168

Share-based Compensation - Summary of Restricted Stock and Restricted Stock Unit, Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares
Restricted Stock Awards
Number of Shares
Unvested beginning balance (in shares)	599,421
Granted (in shares)	0
Vested (in shares)	(175,806)
Forfeited (in shares)	0
Unvested ending balance (in shares)	423,615
Unrecognized compensation expense excluding options \| $	$ 7,940
Expected weighted average recognition period	1 year 9 months 18 days
Restricted stock units
Number of Shares
Unvested beginning balance (in shares)	1,804,760
Granted (in shares)	1,427,225
Vested (in shares)	(440,924)
Forfeited (in shares)	(320,807)
Unvested ending balance (in shares)	2,470,254
Unrecognized compensation expense excluding options \| $	$ 10,463
Expected weighted average recognition period	2 years 4 months 24 days
Weighted-Average Grant Date Fair Value Per Share
Unvested beginning balance (in dollars per share) \| $ / shares
Granted (in dollars per share) \| $ / shares	3.85
Unvested ending balance (in dollars per share) \| $ / shares

Share-based Compensation - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 7,213	$ 5,603	$ 14,403	$ 11,321
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	3,255	2,654	6,539	5,487
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense recognized	$ 3,958	$ 2,949	$ 7,864	$ 5,834

Fair Value Measurement

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurement

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

The Company follows the provisions of FASB ASC Topic 820, Fair Value Measurement, for financial assets and liabilities measured on a recurring basis. The guidance requires fair value measurements be classified and disclosed in one of the following three categories:

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

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

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

The following fair value hierarchy table presents information about the Company’s financial assets and liabilities 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)
June 30, 2023
Assets
Money Market fund	$	33,889	$	—	$	—
U.S. Treasury securities	158,367		—		—

Liabilities
Note Purchase Agreement	$	—	$	—	$	73,300


December 31, 2022
Liabilities
Note Purchase Agreement	$	—	$	—	$	69,800

We classify our investments in available-for-sale U.S. Treasury securities and the money market fund into Level 1 of the ASC Topic 820 hierarchy because fair values represent quoted market prices for identical or comparable instruments.

The following represents the amortized cost bases and fair values of the Company’s U.S. Treasury securities and its money market fund as of June 30, 2023 (amounts in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money Market fund, included in Cash and cash equivalents	$	33,889	$	—	$	—	$	33,889

U.S. Treasury securities, included in:
Short-term investments	157,337		1,036		(6)		158,367
Total U.S. Treasury securities	$	157,337	$	1,036	$	(6)	$	158,367

For the Company's financial instruments measured at fair value on a recurring basis using significant unobservable inputs (Level 3), the following table provides a reconciliation of the beginning and ending balances for each category therein (amounts in thousands):


	Contingent Value Rights		Note Purchase Agreement
Balance at January 1, 2022	$	37,700	$	75,700
Change in fair value	1,980		(5,900)
Settlement	(39,680)		—
Balance at December 31, 2022	$	—	$	69,800
Change in fair value	—		3,500
Balance at June 30, 2023	$	—	$	73,300

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 six months ended June 30, 2023, the Company recorded an unrealized loss of $3.5 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 unrealized loss was primarily the result of the accretion of discount as well as a decrease in the discount rate due to a lower risk free rate and a decrease in credit spreads.

- 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

Subsequent Event (Details) - At-the-market - USD ($) $ in Millions	Aug. 14, 2023	Jan. 27, 2023	Jul. 12, 2022
Subsequent Event [Line Items]
Sale of stock, consideration receivable (up to)		$ 125.0	$ 350.0
Subsequent Event
Subsequent Event [Line Items]
Shares sold in offering (in shares)	2,040,816
Aggregate net proceeds	$ 14.6

Summary of Significant Accounting Policies - Note Purchase Agreement (Details) - USD ($) $ in Millions		1 Months Ended
	Feb. 11, 2022	Oct. 31, 2021	Oct. 04, 2021
Debt Instrument [Line Items]
Debt instrument, term	6 years
Oberland Capital
Debt Instrument [Line Items]
Note purchase agreement, value	$ 300	$ 300	$ 75
Note purchase agreement, amount available for funding at the option of the company		125
Note purchase agreement, amount available for funding at the option of the company and counterparty	$ 100	$ 100
Oberland Capital \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, term		6 years

- Definition

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

+ References

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+ Details

Organization and Description of Business	6 Months Ended
Organization and Description of Business	Jun. 30, 2023
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 that aims to discover, develop and ultimately deliver medicines that are transformational for 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, it re-registered Centessa Pharmaceuticals Limited as an English public limited company and renamed it as Centessa Pharmaceuticals plc. Risks and Liquidity The Company is subject to risks common to other life science companies in various stages of development including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on key personnel, market acceptance of products, product liability, protection of proprietary technology, ability to raise additional financing and compliance with government regulations in the markets in which the Company is seeking approvals, including U.S. Food and Drug Administration (“FDA”) regulations. If the Company does not successfully advance its programs, 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 Company has incurred losses and negative cash flows from operations since inception and the Company had an accumulated deficit of $(677.5) million as of June 30, 2023. The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of the product candidates currently in development. Substantial additional capital will be needed by the Company to fund its operations and to develop its product candidates. The Company expects its existing cash, cash equivalents and short-term investments as of June 30, 2023 of $303.6 million will be sufficient to fund its expected operating expenses and capital expenditure requirements for at least the next twelve months from the date of issuance of these unaudited interim consolidated financial statements. Shelf Registration Statement On July 12, 2022, the Securities and Exchange Commission (“SEC”) declared effective the Company’s filed shelf registration statement on Form S-3 (“Shelf”), which covers the offering, issuance and sale of an amount up to $350.0 million in the aggregate of the Company’s ordinary shares, American Depository Shares representing ordinary shares, debt securities, warrants, and/or units or any combination thereof. The Company entered into a Sales Agreement, dated January 27, 2023, by and between Centessa Pharmaceuticals plc and Leerink Partners LLC (formerly SVB Securities LLC). As sales agent, Leerink Partners LLC will provide for the issuance and sale by the Company of up to $125.0 million of its ordinary shares represented by American Depository Shares from time to time in “at-the-market” offerings under the Shelf (“ATM Program”). As of June 30, 2023, the Company has not issued any securities under the ATM Program.

Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023
Statement of Stockholders' Equity [Abstract]
Unrealized gain on available for sale securities, tax	$ 0.2	$ 0.2

Income Taxes (Details) - USD ($)	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($)	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Income tax benefit	$ 24,051,000	$ 22,000	$ 23,374,000	$ (58,000)

- Definition

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

+ References + Details

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying unaudited interim consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) promulgated by the Financial Accounting Standards Board (“FASB”). In the opinion of management, the accompanying unaudited interim consolidated 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 June 30, 2023 and as of December 31, 2022; •the Company’s results of operations for the three and six months ended June 30, 2023 and June 30, 2022; and •the Company’s cash flows for the six months ended June 30, 2023 and June 30, 2022. Operating results for the Company for the three and six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the full year. The unaudited interim consolidated financial statements presented herein do not contain all of the required disclosures under U.S. GAAP for annual financial statements. Notes to the financial statements which would substantially duplicate the disclosure contained in the audited financial statements for fiscal 2022 as reported in the 2022 Annual Report have been omitted. Therefore, these unaudited interim consolidated financial statements should be read in conjunction with the annual audited consolidated and combined financial statements and related notes for Centessa Pharmaceuticals plc found in the Form 10-K filed with the SEC. The Company’s unaudited interim consolidated financial statements include the accounts of Centessa Pharmaceuticals plc, and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
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, money market funds and U.S. Treasury securities.
Short Term Investments	Short Term Investments The Company invests its excess cash in cash deposits, U.S. Treasury securities and SEC-registered money market funds. Securities with original maturities of three months or less when purchased are included in Cash and cash equivalents. The Company considers investments with original maturities greater than three months and remaining maturities less than one year to be short-term investments. As of June 30, 2023, all investments in U.S. Treasury securities were classified as available-for-sale securities, which are recorded at fair value. Unrealized holding gains and losses on available-for-sale securities are reported net of related income taxes in accumulated other comprehensive income until realized. Purchase premiums and discounts are amortized to interest income over the terms of the related securities.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash, cash equivalents and short-term investments. The Company’s cash, cash equivalents and short-term investments are held by financial institutions primarily in the United States and the United Kingdom. Amounts on deposit may at times exceed federally insured limits. Management believes that the financial institutions are financially sound, and accordingly, the Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.
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.
Use of Estimates	Use of Estimates The preparation of unaudited interim consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the unaudited interim consolidated financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates. Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the unaudited interim consolidated financial statements in the period they are determined to be necessary. Significant areas that require management’s estimates include share-based compensation assumptions, note purchase agreement assumptions, and accrued research and development expenses.
Property and Equipment, net and Capitalized Software under Cloud Computing Arrangements	Property and Equipment, net and Capitalized Software under Cloud Computing ArrangementsProperty and equipment are recorded at cost and are depreciated using the straight-line method over the estimated useful lives of the respective assets. Property and equipment includes computer equipment, furniture and office equipment. 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. Costs related to the implementation of cloud computing arrangements that are service contracts incurred during the application development stage are capitalized and included in the same line item as a prepayment for corresponding hosting service fees. Capitalized costs are amortized over the shorter of its estimated useful life and the term of the hosting arrangement, including anticipated extensions. Costs incurred during the preliminary project stage and the post-implementation-operation stage are expensed as incurred. Hosting fees associated with hosting as a service arrangement are expensed on a straight line basis over the term of the hosting arrangement.
Leases	Leases In accordance with ASU No. 2016-02, Leases (“ASC 842”), the Company assesses whether an arrangement is a lease, or contains a lease at the inception of the arrangement. When an arrangement contains a lease, the Company categorizes leases with contractual terms longer than twelve months as either operating or finance. Finance leases are generally those leases that allow us to substantially utilize or pay for the entire asset over its estimated life. Assets acquired under finance leases are recorded in “Property and equipment, net.” All other leases are categorized as operating leases. The Company records right-of use ("ROU") assets and lease obligations for its finance and operating leases, which are initially recognized based on the discounted future lease payments over the term of the lease. As the rate implicit in the Company's leases may not be easily determinable, the Company uses its incremental borrowing rate to calculate the present value of the sum of the lease payments. Lease terms may include options to extend or terminate the lease. The Company will include such options in determining the lease term when it is reasonably certain that the Company will exercise such options. Operating and finance lease ROU assets are recognized net of any lease prepayments and incentives. The Company elected the practical expedient to not separate lease and non-lease components and, accordingly, accounts for them as a single lease component. Operating lease expense is recognized on a straight-line basis over the lease term. Finance lease expense is recognized based on the effective-interest method over the lease term. The Company elected not to recognize ROU assets and lease obligations for any short-term leases, which are defined as leases with an initial term of 12 months or less.
Long-Lived Assets	Long-Lived Assets Long-lived assets, comprised of property and equipment and operating lease right-of-use 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. No impairments of long-lived assets for the six-month periods ended June 30, 2023 and 2022 were recognized by the Company.
Note Purchase Agreement	Note Purchase Agreement In October 2021, the Company entered into a Note Purchase Agreement (the “Note Purchase Agreement”) with Oberland Capital. Under the terms of the Note Purchase Agreement, Oberland Capital will purchase up to $300 million of 6.0 years, interest-only, senior secured notes (the “Notes”) from the Company including $75 million funded on October 4, 2021, $125 million available through 2023 at the Company’s option, and $100 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 a milestone payment upon the Company’s first product to obtain regulatory approval and was obligated to pay revenue participation payments, starting on the date of the first commercial sale of lixivaptan. Since the Company’s discontinuation of the development of lixivaptan for the treatment of ADPKD, the revenue participation payment is no longer achievable. 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 Note Purchase 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.
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.

Commitments and Contingencies - Narrative (Details)	12 Months Ended
Commitments and Contingencies - Narrative (Details)	Dec. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Feb. 07, 2022 USD ($) ft² option
Lessee, Lease, Description [Line Items]
Purchase obligation		$ 33,200,000
Purchase obligation, to be paid, within one year		28,600,000
Purchase obligation, to be paid, over one to four years		4,600,000
Lease term				10 years
Area of real estate property \| ft²				18,922
Letter of credit outstanding				$ 700,000
Number of options to extend \| option				1
Lease, renewal term				5 years
Operating lease, right-of-use asset		12,342,000	$ 0
Operating lease liabilities		9,608,000
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Lessee, Lease, Description [Line Items]
Maximum aggregate development and regulatory milestone payments		0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Orexia
Lessee, Lease, Description [Line Items]
Maximum aggregate development milestone payments		44,400,000
Maximum aggregate commercial milestone payments		$ 42,000,000
Forecast
Lessee, Lease, Description [Line Items]
Rent expense	$ 1,600,000
Rent expense, year 10	$ 1,900,000

Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of Balance Sheet Information Related to Leases

The following table provides balance sheet information related to leases as of June 30, 2023 (amounts in thousands):


	June 30, 2023
Assets:
Operating lease, right-of-use asset	$	12,342

Liabilities:
Current portion of operating lease liabilities	$	460
Operating lease liabilities, net of current portion	9,148
Total operating lease liabilities	$	9,608

Schedule of Lease, Cost

The following table summarizes supplemental information related to leases as of June 30, 2023 (amount in thousands):


	June 30, 2023
Weighted-average remaining lease term	9.6 years
Weighted-average discount rate	11.97	%

The components of the Company’s lease costs are classified on its consolidated statements of operations as follows (amounts in thousands):


	Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Operating lease cost	$	499	$	—
Variable lease cost	44		39
Short term lease cost	15		61
Total operating lease cost	$	558	$	100

Schedule of Lessee, Operating Lease, Liability, Maturity

Future lease payments under non-cancelable operating leases as of June 30, 2023 were as follows (amounts in thousands):


	Operating Leases
Year ending:
2023	$	785
2024	1,602
2025	1,634
2026	1,667
2027	1,700
Thereafter	9,023
Total	$	16,411
Less: Imputed interest	(6,803)
Present value of lease liabilities	$	9,608
Less: current portion	(460)
Lease liabilities, net of current portion	$	9,148

Debt

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Debt

Debt as of June 30, 2023 and December 31, 2022 (in thousands):


	June 30, 2023		December 31, 2022
Note Purchase Agreement	$	73,300	$	69,800

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 Oberland Capital Management LLC (the “Purchasers”) and Cocoon SA LLC (the “Agent”), an affiliate of Oberland Capital Management LLC, as agent for the Purchasers. On February 11, 2022, on November 7, 2022 and on June 23, 2023, the Company, the Guarantors, the Purchasers and the Agent agreed to certain amendments to the Note Purchase Agreement, memorialized in the “Amendment”, the “Second Amendment”, and the “Third Amendment” respectively. The Note Purchase Agreement, collectively with the amendments, is hereinafter referred to as the NPA.

Under the NPA, the Purchasers agreed to purchase, and the Company agreed to sell, tranches of secured notes in the aggregate principal amount of up to $300 million as follows: (a) a secured note in the aggregate principal amount of $75 million, (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 million (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 million (the “Third Purchase Note”), and (d) one or more secured notes in the aggregate principal amount of up to $100 million at any time at the Company’s and Purchasers’ option, to be used to finance certain permitted acquisitions as described in the NPA (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 NPA. 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) the Secured Overnight Financing Rate (“SOFR”) (which may be subject to replacement as contemplated by the NPA) and (ii) 0.25%; plus (b) 7.75% (which percentage is subject to adjustment as described in the NPA); provided that the interest rate shall never be less than 8.00%. The average interest rate over the six months ended June 30, 2023 was 12.7% per annum compared with an average interest rate of 8.4% per annum over the six months ended June 30, 2022.

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.

Upon the first regulatory approval of any of the Company’s product candidates by either the 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 NPA. 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 NPA, including amounts paid by the Company to the Purchasers in respect of certain asset sale or strategic transactions, the interest payments and the Milestone Payments (the “Final Payment Amount”). As of June 30, 2023, the cumulative payments under the NPA, including interest payments, totaled $13.6 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 NPA and related transaction documents, an event of default under the NPA or the tenth anniversary of the First Purchase Date (or such earlier date as described in the NPA). 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 NPA (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 NPA) received from such asset sales, 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 (the “Deductible”).

The NPA 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 in the amount of 90% of the aggregate outstanding principal amount of all issued Notes, maintenance of insurance and addition of new subsidiaries as obligors. It also contains customary representations and warranties in favor of the Purchasers and the Agent and 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 the Nasdaq Global Select Market.

- 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://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Consolidated Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating expenses:
Research and development	$ 33,673,000	$ 53,651,000	$ 66,499,000	$ 90,504,000
General and administrative	13,346,000	14,763,000	29,397,000	29,148,000
Change in fair value of contingent value rights	0	0	0	1,980,000
Loss from operations	(47,019,000)	(68,414,000)	(95,896,000)	(121,632,000)
Interest income	2,059,000	25,000	4,590,000	129,000
Interest expense	(2,450,000)	(1,653,000)	(4,795,000)	(3,153,000)
Other (expense) income, net	(1,527,000)	5,359,000	(2,873,000)	5,555,000
Loss before income taxes	(48,937,000)	(64,683,000)	(98,974,000)	(119,101,000)
Income tax (benefit) expense	(24,051,000)	(22,000)	(23,374,000)	58,000
Net loss	(24,886,000)	(64,661,000)	(75,600,000)	(119,159,000)
Other comprehensive income (loss):
Foreign currency translation adjustment	762,000	(1,124,000)	1,660,000	(1,830,000)
Unrealized gain on available for sale securities, net of tax	783,000	0	783,000	0
Other comprehensive income (loss)	1,545,000	(1,124,000)	2,443,000	(1,830,000)
Total comprehensive loss	$ (23,341,000)	$ (65,785,000)	$ (73,157,000)	$ (120,989,000)
Net loss per ordinary share - basic (in dollars per share)	$ (0.26)	$ (0.69)	$ (0.80)	$ (1.29)
Net loss per ordinary share - diluted (in dollars per share)	$ (0.26)	$ (0.69)	$ (0.80)	$ (1.29)
Weighted average ordinary shares outstanding - basic (in shares)	95,162,734	94,109,089	95,050,940	92,317,172
Weighted average ordinary shares outstanding - diluted (in shares)	95,162,734	94,109,089	95,050,940	92,317,172

Commitments and Contingencies - Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets:
Operating lease, right-of-use asset	$ 12,342	$ 0
Liabilities:
Current portion of operating lease liabilities	460	0
Operating lease liabilities, net of current portion	9,148	$ 0
Present value of lease liabilities	$ 9,608

Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Share-based Compensation Expense

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


	Three Months Ended June 30, 2023		Three Months Ended June 30, 2022		Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Research and development	$	3,255	$	2,654	$	6,539	$	5,487
General and administrative	3,958		2,949		7,864		5,834
	$	7,213	$	5,603	$	14,403	$	11,321

Summary of Stock Option Activity

The following table summarizes stock option activity for the six months ended June 30, 2023:


	Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term
Balance at January 1, 2023	14,688,996	$	7.88	8.5 years
Granted	2,818,300	$	4.13
Exercised	(3,776)	$	3.85
Forfeited	(1,456,693)	$	8.39
Balance at June 30, 2023	16,046,827	$	7.18	8.2 years
Exercisable at June 30, 2023	6,858,127	$	7.61	7.6 years
Vested and expected to vest at June 30, 2023	16,046,827	$	7.18	8.2 years

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

During the six months ended June 30, 2023, the fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below:


Expected term	6.0 years
Expected stock price volatility	77.9	%
Risk-free interest rate	3.6	%
Expected dividend yield	0	%

Summary of Replacement Equity Award Activity

The following table summarizes ordinary share activity related to the restricted stock programs for the six months ended June 30, 2023:


	Restricted Stock Awards			Restricted Stock Units
	Number of Shares		Weighted-Average Grant Date Fair Value Per Share	Number of Shares		Weighted-Average Grant Date Fair Value Per Share
Unvested at January 1, 2023	599,421			1,804,760
Granted	—		n/a	1,427,225		$	3.85
Vested	(175,806)			(440,924)
Forfeited	—			(320,807)
Unvested at June 30, 2023	423,615			2,470,254

Unrecognized compensation expense at June 30, 2023 (in thousands)	$	7,940		$	10,463
Expected weighted average recognition period	1.8 years			2.4 years

Share-based Compensation - Summary of Stock Option Activity (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	14,688,996
Granted (in shares) \| shares	2,818,300
Exercised (in shares) \| shares	(3,776)
Forfeited (in shares) \| shares	(1,456,693)
Ending balance (in shares) \| shares	16,046,827	14,688,996
Exercisable at end of period (in shares) \| shares	6,858,127
Vested and expected to vest at end of period (in shares) \| shares	16,046,827
Weighted-Average Exercise Price Per Share
Beginning balance (in dollars per share) \| $ / shares	$ 7.88
Granted (in dollars per share) \| $ / shares	4.13
Exercised (in dollars per share) \| $ / shares	3.85
Forfeited (in dollars per share) \| $ / shares	8.39
Ending balance (in dollars per share) \| $ / shares	7.18	$ 7.88
Exercisable at end of period (in dollars per share) \| $ / shares	7.61
Vested and expected to vest at end of period (in dollars per share) \| $ / shares	$ 7.18
Weighted-Average Remaining Contractual Term
Options outstanding, weighted-average remaining contractual term	8 years 2 months 12 days	8 years 6 months
Options exercisable, weighted-average remaining contractual term	7 years 7 months 6 days
Options vested and expected to vest at end of period, weighted-average remaining contractual term	8 years 2 months 12 days

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Note Purchase Agreement
Debt Instrument [Line Items]
Long-term debt, gross	$ 73,300	$ 69,800

- Definition

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

+ References

+ Details

Debt - Narrative (Details) - USD ($)			1 Months Ended	6 Months Ended
Debt - Narrative (Details) - USD ($)	Nov. 07, 2022	Feb. 11, 2022	Oct. 31, 2021	Jun. 30, 2023	Jun. 30, 2022	Oct. 04, 2021
Debt Instrument [Line Items]
Debt instrument, term		6 years
Debt instrument, reference rate		7.75%
Weighted average interest rate				12.70%	8.40%
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				$ 13,600,000
Note purchase agreement, deductible amount due to company				$ 100,000,000
Note purchase agreement, percent of aggregate outstanding principal amount, cash balance required	90.00%
Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.25%
Note Purchase Agreement
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage of principal amount redeemed				75.00%
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%
Oberland Capital
Debt Instrument [Line Items]
Note purchase agreement, value		$ 300,000,000	$ 300,000,000			$ 75,000,000
Note purchase agreement, amount available for funding at the option of the company and counterparty		100,000,000	$ 100,000,000
Oberland Capital \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, term			6 years
Oberland Capital \| Second Purchase Note
Debt Instrument [Line Items]
Note purchase agreement, value		75,000,000
Oberland Capital \| Third Purchase Note
Debt Instrument [Line Items]
Note purchase agreement, value		$ 50,000,000
Oberland Capital \| Interest Only, Senior Secured Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, interest rate floor		8.00%

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-Average Ordinary Shares Outstanding (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
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)	18,940,696	16,236,756
Unvested 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)	423,615	715,432
Restricted stock units
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)	2,470,254	0
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)	16,046,827	15,521,324

Summary of Significant Accounting Policies - Property and Equipment, net (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Accounting Policies [Abstract]
Depreciation expense	$ 121	$ 60
Capitalized computer software, amortization	$ 204

Fair Value Measurement - Narrative (Details) $ in Millions	6 Months Ended
Fair Value Measurement - Narrative (Details) $ in Millions	Jun. 30, 2023 USD ($)
Note Purchase Agreement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value	$ 3.5

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 145,220	$ 393,644
Short-term investments	158,367	0
Tax incentive receivable	27,151	24,166
Prepaid expenses and other current assets	19,675	19,937
Total current assets	350,413	437,747
Property and equipment, net	1,145	1,168
Operating lease right-of-use assets	12,342	0
Deferred tax asset	26,754	3,512
Other, net	2,267	1,880
Total assets	392,921	444,307
Current liabilities:
Accounts payable	11,085	13,836
Accrued expenses and other current liabilities	22,782	24,502
Total current liabilities	33,867	38,338
Long term debt	73,300	69,800
Operating lease liabilities	9,148	0
Total liabilities	116,315	108,138
Commitments and contingencies (Note 6)
Shareholders’ equity:
Ordinary shares: £0.002 nominal value: 152,500,000 shares authorized, 95,299,673 issued and outstanding at June 30, 2023: 152,500,000 shares authorized, 94,843,391 issued and outstanding at December 31, 2022	266	265
Additional paid-in capital	952,854	939,261
Accumulated other comprehensive loss	946	(1,497)
Accumulated deficit	(677,460)	(601,860)
Total shareholders' equity	276,606	336,169
Total liabilities and shareholders' equity	$ 392,921	$ 444,307

Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Commitments

As of June 30, 2023, the Company had non-cancellable commitments for purchase of clinical materials, contract manufacturing, maintenance, and committed funding of up to $33.2 million, of which the Company expects to pay $28.6 million within one year and $4.6 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.

Leases

On February 7, 2022, the Company entered into an operating lease for its new corporate headquarters in Boston, Massachusetts (the “Boston Lease”). After a build out of the space, the Boston Lease commenced on March 31, 2023. The 10-year Boston Lease is for 18,922 square feet with a fixed annual rent of approximately $1.6 million commencing in 2023 and escalating to approximately $1.9 million by year 10. The Boston Lease required the Company to issue a letter of credit in the amount of $0.7 million in favor of the landlord. The Company may, at its discretion, extend the Boston Lease for one extension term of five years. As of June 30, 2023, the Company has recognized an operating lease right-of-use asset, net of $12.3 million, including capitalized leasehold improvements that will be owned by the landlord, prepayments of rent, and a corresponding lease liability of $9.6 million. The Company intends to sublet a portion of the Boston Lease.

The following table provides balance sheet information related to leases as of June 30, 2023 (amounts in thousands):


	June 30, 2023
Assets:
Operating lease, right-of-use asset	$	12,342

Liabilities:
Current portion of operating lease liabilities	$	460
Operating lease liabilities, net of current portion	9,148
Total operating lease liabilities	$	9,608

In calculating the present value of the lease payments, the Company elected to utilize its incremental borrowing rate based on the original term of the lease. The following table summarizes supplemental information related to leases as of June 30, 2023 (amount in thousands):


	June 30, 2023
Weighted-average remaining lease term	9.6 years
Weighted-average discount rate	11.97	%

The components of the Company’s lease costs are classified on its consolidated statements of operations as follows (amounts in thousands):


	Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Operating lease cost	$	499	$	—
Variable lease cost	44		39
Short term lease cost	15		61
Total operating lease cost	$	558	$	100

Future lease payments under non-cancelable operating leases as of June 30, 2023 were as follows (amounts in thousands):


	Operating Leases
Year ending:
2023	$	785
2024	1,602
2025	1,634
2026	1,667
2027	1,700
Thereafter	9,023
Total	$	16,411
Less: Imputed interest	(6,803)
Present value of lease liabilities	$	9,608
Less: current portion	(460)
Lease liabilities, net of current portion	$	9,148

Licensing and Collaborative Arrangements

The Company is party to licensing and collaboration arrangements to develop and commercialize intellectual property. In aggregate, the Company may be obligated to make up to $44.4 million and $42.0 million in related development and commercial milestone payments, respectively, predominately related to agreements between Orexia Therapeutics Limited and collaboration partners. As of June 30, 2023, the Company had no significant milestone obligations recorded on its balance sheet

under its license and collaborative arrangements. The Company expects that payments related to its licensing and collaboration arrangements in the next twelve months would not be material to the Company’s consolidated financial statements.

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

On September 28, 2022 (“Original Complaint”), the Company and certain of its current and former officers were named as defendants in a proposed class-action lawsuit filed in the United States District Court for the Central District of California. The complaint generally alleges that the Company violated Sections 10(b) and 20(a) and Sections 11 and 15 of the Securities Act of 1933, as amended (the “Securities Act”) by allegedly making materially false and/or misleading statements, as well as allegedly failing to disclose material adverse facts relating to the safety profile and future clinical and commercial prospects of each of its lixivaptan and ZF874 programs, which caused the Company’s securities to trade at artificially inflated prices. On October 12, 2022, by order, the lawsuit was transferred to the United States District Court for the Southern District of New York. On February 10, 2023, an amended complaint was filed (“Amended Complaint”) in which our IPO underwriters were added as co-defendants. A number of the complaints set forth in the Original Complaint have been abandoned including with respect to intentional fraud theory and claims pursuant to Sections 10(b) or 20(a) of the Securities Exchange Act of 1934. The only claims alleged in the Amended Complaint are violations of Sections 11 and 15 of the Securities Act based on alleged misstatements in the S-1 filed by the Company in connection with its Initial Public Offering. The Amended Complaint also abandoned any claims concerning ZF874 and focuses entirely on lixivaptan. The Amended Complaint seeks damages and attorneys’ fees, among other things. The Company believes this lawsuit is without merit and intends to defend the case vigorously. Litigation is subject to inherent uncertainty and a court could ultimately rule against the Company. In addition, the defense of litigation and related matters are costly and may divert the attention of the Company’s management and other resources that would otherwise be engaged in other activities. The Company has not recorded an estimate of the possible loss associated with this legal proceeding due to the uncertainties related to both the likelihood and the amount of any possible loss or range of loss.

Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Related Party Transaction [Line Items]
Research and development	$ 33,673	$ 53,651	$ 66,499	$ 90,504
Master Service Agreements \| Related Party
Related Party Transaction [Line Items]
Research and development	$ 2,292	$ 1,420	$ 4,614	$ 3,119

Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

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

The following fair value hierarchy table presents information about the Company’s financial assets and liabilities 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)
June 30, 2023
Assets
Money Market fund	$	33,889	$	—	$	—
U.S. Treasury securities	158,367		—		—

Liabilities
Note Purchase Agreement	$	—	$	—	$	73,300


December 31, 2022
Liabilities
Note Purchase Agreement	$	—	$	—	$	69,800

Schedule of Debt Securities, Fair Value of U.S. Treasury Securities and Money Market Fund

The following represents the amortized cost bases and fair values of the Company’s U.S. Treasury securities and its money market fund as of June 30, 2023 (amounts in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money Market fund, included in Cash and cash equivalents	$	33,889	$	—	$	—	$	33,889

U.S. Treasury securities, included in:
Short-term investments	157,337		1,036		(6)		158,367
Total U.S. Treasury securities	$	157,337	$	1,036	$	(6)	$	158,367

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


	Contingent Value Rights		Note Purchase Agreement
Balance at January 1, 2022	$	37,700	$	75,700
Change in fair value	1,980		(5,900)
Settlement	(39,680)		—
Balance at December 31, 2022	$	—	$	69,800
Change in fair value	—		3,500
Balance at June 30, 2023	$	—	$	73,300

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Share-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	6 Months Ended
	Jan. 01, 2022	Jan. 31, 2021	Jun. 30, 2023	May 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value of options granted (in dollars per share)			$ 2.87
Unrecognized compensation expense related to unvested stock option awards			$ 38.5
Share price (in dollars per share)			$ 6.19
Aggregate intrinsic value of options			$ 9.9
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average recognition period			2 years 3 months 18 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average recognition period			1 year 9 months 18 days
Share-based payment awards issued in period (in shares)		379,905
Restricted Stock 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	2,708,315
Share-based compensation, percentage of outstanding stock maximum	1.00%
Multiplier for initial number of shares reserved	2
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for equity incentive plan (in shares)				20,026,816
Percent of additional shares authorized each year			5.00%
Shares available for grant (in shares)			8,284,827

Summary of Significant Accounting Policies - Long-Lived Assets (Details) - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Accounting Policies [Abstract]
Impairment, long-lived asset	$ 0	$ 0

Commitments and Contingencies - Components of Lease Expense (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 499	$ 0
Variable lease cost	44	39
Short term lease cost	15	61
Total operating lease cost	$ 558	$ 100

Related Party Transactions

6 Months Ended

Jun. 30, 2023

Related Party Transactions

Master Services agreements with drug discovery companies affiliated with David Grainger

Certain Centessa subsidiaries 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 incurred research and development costs associated with these contracts as follows in the consolidated statements of operations and comprehensive loss (amounts in thousands):


	Three Months Ended June 30, 2023		Three Months Ended June 30, 2022		Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Research and development	$	2,292	$	1,420	$	4,614	$	3,119

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

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

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Commitments and Contingencies - Future Lease Payments under Non-Cancelable Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Operating Leases
2023	$ 785
2024	1,602
2025	1,634
2026	1,667
2027	1,700
Thereafter	9,023
Total	16,411
Less: Imputed interest	(6,803)
Present value of lease liabilities	9,608
Less: current portion	(460)	$ 0
Operating lease liabilities, net of current portion	$ 9,148	$ 0

Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development expenses	$ 15,147	$ 10,795
Personnel related expenses	4,510	7,264
Professional fees	2,158	4,171
Income tax liability	0	1,582
Operating lease liabilities	460	0
Other	507	690
Accrued expenses and other current liabilities	$ 22,782	$ 24,502

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

The accompanying unaudited interim consolidated financial statements should be read in conjunction with the annual audited consolidated and combined financial statements of Centessa Pharmaceuticals plc (Successor) and the Centessa Predecessor Group (Predecessor) and related notes as of and for the year ended December 31, 2022 which can be found in our Annual Report on Form 10-K for the year ended December 31, 2022 (the “2022 Annual Report”). The Summary of Significant Accounting Policies included in the Company’s annual financial statements have not materially changed, except as set forth below.

Basis of Presentation and Consolidation

The accompanying unaudited interim consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable

guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) promulgated by the Financial Accounting Standards Board (“FASB”).

In the opinion of management, the accompanying unaudited interim consolidated 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 June 30, 2023 and as of December 31, 2022;

•the Company’s results of operations for the three and six months ended June 30, 2023 and June 30, 2022; and

•the Company’s cash flows for the six months ended June 30, 2023 and June 30, 2022.

Operating results for the Company for the three and six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the full year. The unaudited interim consolidated financial statements presented herein do not contain all of the required disclosures under U.S. GAAP for annual financial statements. Notes to the financial statements which would substantially duplicate the disclosure contained in the audited financial statements for fiscal 2022 as reported in the 2022 Annual Report have been omitted. Therefore, these unaudited interim consolidated financial statements should be read in conjunction with the annual audited consolidated and combined financial statements and related notes for Centessa Pharmaceuticals plc found in the Form 10-K filed with the SEC.

The Company’s unaudited interim consolidated financial statements include the accounts of Centessa Pharmaceuticals plc, and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Emerging Growth Company and Smaller Reporting 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 $1.235 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 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.

We are also a “smaller reporting company” as defined in the Securities Exchange Act of 1934 (“Exchange Act”). 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 $560 million if our annual revenue is less than $100 million) as of June 30 in any given year. As a smaller reporting company, we are eligible for scaled disclosure relief from certain Regulation S-X and Regulation S-K requirements.

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, money market funds and U.S. Treasury securities.

Short Term Investments

The Company invests its excess cash in cash deposits, U.S. Treasury securities and SEC-registered money market funds. Securities with original maturities of three months or less when purchased are included in Cash and cash equivalents. The Company considers investments with original maturities greater than three months and remaining maturities less than one year to be short-term investments.

As of June 30, 2023, all investments in U.S. Treasury securities were classified as available-for-sale securities, which are recorded at fair value. Unrealized holding gains and losses on available-for-sale securities are reported net of related income taxes in accumulated other comprehensive income until realized. Purchase premiums and discounts are amortized to interest income over the terms of the related securities.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash, cash equivalents and short-term investments. The Company’s cash, cash equivalents and short-term investments are held by financial institutions primarily in the United States and the United Kingdom. Amounts on deposit may at times exceed federally insured limits. Management believes that the financial institutions are financially sound, and accordingly, the Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

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.

Use of Estimates

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

Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the unaudited interim consolidated financial statements in the period they are determined to be necessary. Significant areas that require management’s estimates include share-based compensation assumptions, note purchase agreement assumptions, and accrued research and development expenses.

Property and Equipment, net and Capitalized Software under Cloud Computing Arrangements

Property and equipment are recorded at cost and are depreciated using the straight-line method over the estimated useful lives of the respective assets. Property and equipment includes computer equipment, furniture and office equipment. 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. Depreciation expense for the six-month periods ended June 30, 2023 and June 30, 2022 were $121 thousand and $60 thousand, respectively.

Costs related to the implementation of cloud computing arrangements that are service contracts incurred during the application development stage are capitalized and included in the same line item as a prepayment for corresponding hosting service fees. Capitalized costs are amortized over the shorter of its estimated useful life and the term of the hosting arrangement, including anticipated extensions. Costs incurred during the preliminary project stage and the post-implementation-operation stage are expensed as incurred. Hosting fees associated with hosting as a service arrangement are expensed on a

straight line basis over the term of the hosting arrangement. Amortization expense for the six months ended June 30, 2023 was $204 thousand.

Leases

In accordance with ASU No. 2016-02, Leases (“ASC 842”), the Company assesses whether an arrangement is a lease, or contains a lease at the inception of the arrangement. When an arrangement contains a lease, the Company categorizes leases with contractual terms longer than twelve months as either operating or finance. Finance leases are generally those leases that allow us to substantially utilize or pay for the entire asset over its estimated life. Assets acquired under finance leases are recorded in “Property and equipment, net.” All other leases are categorized as operating leases.

The Company records right-of use ("ROU") assets and lease obligations for its finance and operating leases, which are initially recognized based on the discounted future lease payments over the term of the lease. As the rate implicit in the Company's leases may not be easily determinable, the Company uses its incremental borrowing rate to calculate the present value of the sum of the lease payments. Lease terms may include options to extend or terminate the lease. The Company will include such options in determining the lease term when it is reasonably certain that the Company will exercise such options. Operating and finance lease ROU assets are recognized net of any lease prepayments and incentives. The Company elected the practical expedient to not separate lease and non-lease components and, accordingly, accounts for them as a single lease component. Operating lease expense is recognized on a straight-line basis over the lease term. Finance lease expense is recognized based on the effective-interest method over the lease term. The Company elected not to recognize ROU assets and lease obligations for any short-term leases, which are defined as leases with an initial term of 12 months or less.

Long-Lived Assets

Long-lived assets, comprised of property and equipment and operating lease right-of-use 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. No impairments of long-lived assets for the six-month periods ended June 30, 2023 and 2022 were recognized by the Company.

Note Purchase Agreement

In October 2021, the Company entered into a Note Purchase Agreement (the “Note Purchase Agreement”) with Oberland Capital. Under the terms of the Note Purchase Agreement, Oberland Capital will purchase up to $300 million of 6.0 years, interest-only, senior secured notes (the “Notes”) from the Company including $75 million funded on October 4, 2021, $125 million available through 2023 at the Company’s option, and $100 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 a milestone payment upon the Company’s first product to obtain regulatory approval and was obligated to pay revenue participation payments, starting on the date of the first commercial sale of lixivaptan. Since the Company’s discontinuation of the development of lixivaptan for the treatment of ADPKD, the revenue participation payment is no longer achievable.

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.

probability and timing of an early redemption of all obligations under the Note Purchase 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.

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 six months ended June 30, 2023 and June 30, 2022, as they would be anti-dilutive:


	Six Months Ended June 30, 2023	Six Months Ended June 30, 2022
Unvested ordinary shares	423,615	715,432
Restricted stock units	2,470,254	—
Stock options	16,046,827	15,521,324
	18,940,696	16,236,756

Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2023

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):


	June 30, 2023		December 31, 2022
Research and development expenses	$	12,830	$	11,321
Insurance related expenses	1,704		2,788
Value added tax receivable	1,272		2,557
Other	3,869		3,271
	$	19,675	$	19,937

Schedule of Accrued Expenses and Other Current Liabilities

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


	June 30, 2023		December 31, 2022
Research and development expenses	$	15,147	$	10,795
Personnel related expenses	4,510		7,264
Professional fees	2,158		4,171
Income tax liability	—		1,582
Operating lease liabilities	460		—
Other	507		690
	$	22,782	$	24,502

Schedule of Property and Equipment, Net

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


	June 30, 2023		December 31, 2022
Computer equipment	$	706	$	442
Office furniture	724		—
Other, primarily construction in progress	—		890
Property and equipment, at cost	1,430		1,332
Less: Accumulated depreciation	(285)		(164)
Property and equipment, net	$	1,145	$	1,168

Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and development expenses	$ 12,830	$ 11,321
Insurance related expenses	1,704	2,788
Value added tax receivable	1,272	2,557
Other	3,869	3,271
Prepaid expenses and other current assets	$ 19,675	$ 19,937

Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

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


	Six Months Ended June 30, 2023	Six Months Ended June 30, 2022
Unvested ordinary shares	423,615	715,432
Restricted stock units	2,470,254	—
Stock options	16,046,827	15,521,324
	18,940,696	16,236,756

Organization and Description of Business (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jan. 27, 2023	Dec. 31, 2022	Jul. 12, 2022
Subsidiary, Sale of Stock [Line Items]
Accumulated deficit	$ 677,460		$ 601,860
Cash and cash equivalents and short-term investments	$ 303,600
Sufficient funding term (at least)	12 months
At-the-market
Subsidiary, Sale of Stock [Line Items]
Sale of stock, consideration receivable (up to)		$ 125,000		$ 350,000

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Ordinary Shares	Additional paid-in capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Ordinary shares, beginning balance (in shares) at Dec. 31, 2021		89,988,228
Beginning balance at Dec. 31, 2021	$ 491,554	$ 252	$ 876,267	$ 688	$ (385,653)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of ordinary shares to settle outstanding contingent value rights, net of employee withholding taxes (in shares)		3,938,423
Issuance of ordinary shares to settle outstanding contingent value rights, net of employee withholding taxes	37,748	$ 10	37,738
Stock option exercises (in shares)		77,754
Stock option exercises	405		405
Share-based compensation expense	11,321		11,321
Vesting of ordinary shares (in shares)		267,512
Vesting of ordinary shares	0	$ 1	(1)
Foreign currency translation adjustments	(1,830)			(1,830)
Unrealized gain on available for sale securities, net of tax	0
Net loss	(119,159)				(119,159)
Ordinary shares, ending balance (in shares) at Jun. 30, 2022		94,271,917
Ending balance at Jun. 30, 2022	420,039	$ 263	925,730	(1,142)	(504,812)
Ordinary shares, beginning balance (in shares) at Mar. 31, 2022		94,021,968
Beginning balance at Mar. 31, 2022	480,151	$ 262	920,058	(18)	(440,151)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises (in shares)		18,213
Stock option exercises	70		70
Share-based compensation expense	5,603		5,603
Vesting of ordinary shares (in shares)		231,736
Vesting of ordinary shares	0	$ 1	(1)
Foreign currency translation adjustments	(1,124)			(1,124)
Unrealized gain on available for sale securities, net of tax	0
Net loss	(64,661)				(64,661)
Ordinary shares, ending balance (in shares) at Jun. 30, 2022		94,271,917
Ending balance at Jun. 30, 2022	$ 420,039	$ 263	925,730	(1,142)	(504,812)
Ordinary shares, beginning balance (in shares) at Dec. 31, 2022	94,843,391	94,843,391
Beginning balance at Dec. 31, 2022	$ 336,169	$ 265	939,261	(1,497)	(601,860)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises (in shares)	3,776	3,776
Stock option exercises	$ 15		15
Share-based compensation expense	14,403		14,403
Vesting of ordinary shares (in shares)		616,729
Vesting of ordinary shares	0	$ 1	(1)
Shares withheld to pay employee withholding tax on share-based compensation (in shares)		(164,223)
Shares withheld to pay employee withholding tax on share-based compensation	(824)		(824)
Foreign currency translation adjustments	1,660			1,660
Unrealized gain on available for sale securities, net of tax	783			783
Net loss	$ (75,600)				(75,600)
Ordinary shares, ending balance (in shares) at Jun. 30, 2023	95,299,673	95,299,673
Ending balance at Jun. 30, 2023	$ 276,606	$ 266	952,854	946	(677,460)
Ordinary shares, beginning balance (in shares) at Mar. 31, 2023		95,103,247
Beginning balance at Mar. 31, 2023	293,261	$ 266	946,168	(599)	(652,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises (in shares)		3,776
Stock option exercises	15		15
Share-based compensation expense	7,213		7,213
Vesting of ordinary shares (in shares)		284,437
Shares withheld to pay employee withholding tax on share-based compensation (in shares)		(91,787)
Shares withheld to pay employee withholding tax on share-based compensation	(542)		(542)
Foreign currency translation adjustments	762			762
Unrealized gain on available for sale securities, net of tax	783			783
Net loss	$ (24,886)				(24,886)
Ordinary shares, ending balance (in shares) at Jun. 30, 2023	95,299,673	95,299,673
Ending balance at Jun. 30, 2023	$ 276,606	$ 266	$ 952,854	$ 946	$ (677,460)

Related Party Transactions (Tables)

6 Months Ended

Jun. 30, 2023

Schedule of Related Party Transactions

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


	Three Months Ended June 30, 2023		Three Months Ended June 30, 2022		Six Months Ended June 30, 2023		Six Months Ended June 30, 2022
Research and development	$	2,292	$	1,420	$	4,614	$	3,119

Cover - shares	6 Months Ended
Cover - shares	Jun. 30, 2023	Aug. 04, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Entity Transition Report	false
Entity File Number	001-40445
Entity Registrant Name	CENTESSA PHARMACEUTICALS PLC
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	98-1612294
Entity Address, Address Line One	3rd Floor
Entity Address, Address Line Two	1 Ashley Road
Entity Address, Address Line Three	Altrincham
Entity Address, City or Town	Cheshire
Entity Address, Postal Zip Code	WA14 2DT
Entity Address, Country	GB
Country Region	44
City Area Code	7391
Local Phone Number	789784
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		97,402,945
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001847903
Current Fiscal Year End Date	--12-31
Ordinary Shares
Document Information [Line Items]
Title of 12(b) Security	Ordinary shares, nominal value £0.002 per share
Trading Symbol	CNTA
Security Exchange Name	NASDAQ
American Depositary Shares
Document Information [Line Items]
Title of 12(b) Security	American Depositary Shares, each representing one ordinary share, nominal value £0.002 per share
Trading Symbol	CNTA
Security Exchange Name	NASDAQ

Consolidated Balance Sheets (Parenthetical) - £ / shares	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, nominal value (in pound sterling per share)	£ 0.002	£ 0.002
Common stock, shares authorized (in shares)	152,500,000	152,500,000
Common stock, shares issued (in shares)	95,299,673	94,843,391
Common Stock, shares outstanding (in shares)	95,299,673	94,843,391

Fair Value Measurement - Reconciliation of the Redemption Feature Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Contingent Value Rights
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	$ 37,700
Change in fair value	0	1,980
Settlement		(39,680)
Ending balance	0	0
Note Purchase Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	69,800	75,700
Change in fair value	(3,500)	5,900
Settlement		0
Ending balance	$ 73,300	$ 69,800

Share-based Compensation - Schedule of Assumptions Used to Estimate Fair Value of Stock Option Awards (Details) - Stock options	6 Months Ended
	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 years
Expected stock price volatility	77.90%
Risk-free interest rate	3.60%
Expected dividend yield	0.00%

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Subsequent Event	6 Months Ended
Subsequent Event	Jun. 30, 2023
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventThe Company filed a shelf registration statement on Form S-3 (“the Shelf”) with the Securities and Exchange Commission (SEC), which covers the offering, issuance and sale of an amount up to $350.0 million in the aggregate of our ordinary shares, American Depository Shares representing ordinary shares, debt securities, warrants, and/or units or any combination thereof. On July 12, 2022, the Shelf became effective. The Company entered into a Sales Agreement, dated January 27, 2023, by and between Centessa Pharmaceuticals plc and Leerink Partners LLC (formerly SVB Securities LLC). As sales agent, Leerink Partners LLC will provide for the issuance and sale by the Company of up to $125.0 million of its ordinary shares represented by American Depository Shares from time to time in “at-the-market” offerings under the Shelf, referred to as the ATM Program. In early August 2023, the Company sold 2,040,816 ordinary shares under the ATM Program, resulting in net proceeds to the Company of approximately $14.6 million.