0001828185-24-000011 | 10-K | XBRL Viewer | Barinthus Biotherapeutics PLC

Ordinary Shares

12 Months Ended

Dec. 31, 2023

On May 4, 2021, the Company closed its initial public offering (“IPO”) of 6,500,000 ADS representing 6,500,000 ordinary shares having a nominal value of £0.000025 per share, at a public offering price of $17.00 per share, for aggregate net proceeds of $102.8 million after deducting underwriting commissions of $7.7 million and incurred offering costs of $2.2 million.

All ordinary shares rank pari passu as a single class. The following is a summary of the rights and privileges of the holders of ordinary shares as of December 31, 2023:

Liquidation preference: In the event of the liquidation, dissolution or winding up of the Company, the assets of the Company available for distribution to holders of the ordinary shares shall be distributed amongst all holders of the ordinary shares in proportion to the number of shares held irrespective of the amount paid or credited as paid on any share.

Dividends: Holders of the ordinary shares are entitled to dividends, as may be recommended from time to time by the Board and declared by the ordinary shareholders out of legally available funds.

Voting Rights: Each holder of ordinary shares is entitled to one vote for each share on all matters to be voted on by ordinary shareholders.

Preemption rights: Pursuant to section 561 of the Companies Act 2006, shareholders are granted preemptive rights when new shares are issued for cash. However, it is possible for our Articles, or shareholders at a general meeting representing at least 75% of our ordinary shares present (in person or by proxy) and eligible to vote at that general meeting, to disapply these preemptive rights. Such a disapplication of preemption rights may be for a maximum period of up to five years from the date of the shareholder special resolution. In either case, this disapplication would need to be renewed by our shareholders upon its expiration (i.e., at least every five years) to remain effective.

On April 21, 2021, our shareholders approved the disapplication of preemptive rights for a period of five years from the date of approval by way of a special resolution of our shareholders. This included the disapplication of preemption rights in relation to the allotment of our ordinary shares in connection with the IPO. This disapplication will need to be renewed upon expiration (i.e., at least every five years) to remain effective, but may be sought more frequently for additional five-year terms (or any shorter period).

On November 6, 2023, we held a general meeting where our shareholders approved resolutions granting our board of directors or any duly authorized committee of the board of directors the authority to allot shares in the Company or grant rights to subscribe for or to convert any security into shares in the Company free from preemption rights. Pursuant to such approval, our board of directors was authorized to allot shares up to an aggregate nominal amount of £1,928 free from statutory preemption rights.

As of December 31, 2023, the Company has reserved the following ordinary shares for future issuance:


Exercise of stock options			6,207,664
Shares available for future stock incentive plan awards			1,623,840
Total			7,831,504

- Definition

The entire disclosure for equity.

+ References

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+ Details

Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jan. 01, 2023	Apr. 08, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2018
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares available for future grants (in shares)			6,207,664	4,884,720
Number of shares reserved for issuance (in shares)			7,831,504
Weighted-average grant date fair value (in usd per share)			$ 1.99	$ 3.51
Aggregate intrinsic value of stock options exercised			$ 0.2	$ 0.8
Unrecognized compensation cost related to options			$ 3.0	$ 7.1
Weighted-average period over which unrecognized compensation cost is expected to be recognized			1 year 7 months 6 days
Barinthus Biotherapeutics plc Share Award Plan 2021 \| Restricted share units, options, share appreciation rights and restricted shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares available for issuance (in shares)		3,675,680
Percentage of issued and outstanding ordinary shares available for issuance		4.00%
Additional number of shares available for issuance (in shares)	1,507,341
Expiration period		10 years
Vesting period		3 years
Shares available for future grants (in shares)			1,623,840	1,670,268
Enterprise Management Incentive Share Option Scheme
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period					3 years
Expiration term					10 years
Enterprise Management Incentive Share Option Scheme \| RSU's
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)					3,530,634

Prepaid and other current assets (Tables)

12 Months Ended

Dec. 31, 2023

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of prepaid and other current assets

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


	December 31, 2023		December 31, 2022
Prepayments and accrued income	$	5,402	$	5,887
Value Added Tax receivable	3,031		—

Lease incentives receivable	—		1,770
Other	1,474		611
Total	$	9,907	$	8,268

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Audit Information [Abstract]
Auditor Firm ID	876
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	United Kingdom

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenue recognized	$ 802	$ 44,703
Related parties
Revenue recognized	$ 800	$ 43,700
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	License revenue	License revenue

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
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+ Details

Summary of Significant Accounting Policies - Property and equipment (Details)	Dec. 31, 2023
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Laboratory equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	4 years

Deferred shares	12 Months Ended
Deferred shares	Dec. 31, 2023
Equity [Abstract]
Deferred shares	Deferred shares All deferred shares rank pari passu as a single class. The deferred shares do not have rights to dividends or to participate in profits on a return of assets on liquidation, the deferred shares confer on the holders thereof an entitlement to receive out of the assets of the Company available for distribution amongst the shareholders (subject to the rights of any new class of shares with preferred rights) the amount credited as paid up on the deferred shares held by them respectively after (but only after) payment shall have been made to the holders of the ordinary shares of the amounts paid up or credited as paid up on such shares and the sum of £1.0 million ($1.4 million) in respect of each ordinary share held by them respectively. The deferred shares shall confer on the holders thereof no further right to participate in the assets of the Company. On March 29, 2023, all deferred B shares (nominal value of £0.01 each) and deferred C shares (nominal value of £0.00000736245954692556 each) previously in issue were transferred back to the Company and subsequently cancelled. These deferred shares had previously been issued to certain pre-IPO shareholders in connection with the implementation of certain stages of the Company’s pre-IPO share capital reorganization. The Company received shareholder pre-approval on April 21, 2021 (pursuant to the shareholder resolutions passed on that date) in order to effect the transfer back and cancellation of the deferred shares for nil consideration in accordance with sections 659 and 662 of the Companies Act 2006. The Company’s deferred A shares with a nominal value of £1.00 each remain in issue for the purposes of satisfying the minimum share capital requirements for a public limited company as prescribed by the Companies Act 2006.

Related Party Transactions (Details) - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

Related Party Transactions

Amounts owed to other party

$ 1,601

$ 3,748

Revenue recognized

802

44,703

License revenue

Related Party Transactions

Revenue recognized

^[1]

802

44,694

Related parties

Related Party Transactions

Revenue recognized

800

43,700

Amounts owned from other party

5,524

Shareholder, The University of Oxford | Related parties

Related Party Transactions

Amounts owed to other party

Shareholder, The University of Oxford | Expenses

Related Party Transactions

Amounts of related party transactions

400

Oxford University Innovation Limited | Related parties

Related Party Transactions

Amounts owed to other party

Amounts owned from other party

5,500

Oxford University Innovation Limited | Related parties | License revenue

Related Party Transactions

Revenue recognized

800

43,700

Oxford University Innovation Limited | Expenses

Related Party Transactions

Amounts of related party transactions

$ 600

$ 400

[1]	Includes license revenue from related parties for the year ended December 31, 2023 totaling $0.8 million (December 31, 2022: $43.7 million). License revenue is generated in the United Kingdom.

Fair Value - Change in fair value of contingent consideration (Details) - Contingent consideration liability - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,711	$ 2,371
Change in fair value recognized in net loss	55	(73)
Settlement of contingency	(163)	(325)
Foreign exchange translation recognized in other comprehensive loss	219	(262)
Ending balance	$ 1,823	$ 1,711

Ordinary Shares - Ordinary shares for future issuance (Details) - shares	Dec. 31, 2023	Dec. 31, 2022
Equity [Abstract]
Exercise of stock options	6,207,664	4,884,720
Shares available for future stock incentive plan awards	1,623,840
Total	7,831,504

Nature of Business and Basis of Presentation	12 Months Ended
Nature of Business and Basis of Presentation	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	Nature of Business and Basis of Presentation Nature of business Barinthus Biotherapeutics plc (formerly Vaccitech plc) is a public limited company incorporated pursuant to the laws of England and Wales in March 2021. Barinthus Biotherapeutics plc and its direct and indirect subsidiaries, Barinthus Biotherapeutics (UK) Limited (formerly Vaccitech (UK) Limited), Barinthus Biotherapeutics Australia Pty Limited (formerly Vaccitech Australia Pty Limited), Vaccitech Oncology Limited (“VOLT”), Barinthus Biotherapeutics North America, Inc. (formerly Vaccitech North America, Inc.), Barinthus Biotherapeutics Switzerland GmbH (formerly Vaccitech Switzerland GmbH) and Barinthus Biotherapeutics S.R.L. (formerly Vaccitech Italia S.R.L.), are collectively referred to as the “Company” or “Barinthus Bio”. The Company is a clinical-stage biopharmaceutical company developing novel T cell immunotherapeutic candidates designed to guide the immune system to overcome chronic infectious diseases, autoimmunity and cancer. The Company is headquartered in Harwell, Oxfordshire, United Kingdom. On November 6, 2023, the Company announced its renaming as Barinthus Bio to represent the evolution and expansion of its focus beyond vaccines. In connection with the initial public offering of American Depositary Shares (“ADSs”), in March 2021, the Company completed a corporate reorganization wherein the shareholders of Barinthus Biotherapeutics (UK) Limited exchanged each of their ordinary shares, series A shares and series B shares of Barinthus Biotherapeutics (UK) Limited for the same quantity of ordinary shares, series A shares and series B shares in Barinthus Biotherapeutics plc (resulting in the shareholders of the Company holding the same percentage and class of shares in Barinthus Biotherapeutics plc as they had in Barinthus Biotherapeutics (UK) Limited). The group reorganization under common control constituted a change in reporting entity and has been given retrospective effect reflecting the net assets of Barinthus Biotherapeutics (UK) Limited and its subsidiaries and Barinthus Biotherapeutics plc at their historical carrying amounts. On April 4, 2022, a merger was effected between subsidiaries Vaccitech USA, Inc. and Barinthus Biotherapeutics North America, Inc., with Barinthus Biotherapeutics North America, Inc. being the surviving entity. The Company operates in an environment of rapid technological change and substantial competition from pharmaceutical and biotechnology companies. The Company is subject to risks common to companies in the biopharmaceutical industry in a similar stage of its life cycle including, but not limited to, the need to obtain adequate additional funding, possible failure of preclinical testing or clinical trials, the need to obtain marketing approval for its vaccine product candidates, competitors developing new technological innovations, the need to successfully commercialize and gain market acceptance of any of its products that are approved, and protection of proprietary technology. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain required regulatory approval or that any approved products will be commercially viable. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will generate significant product sales. If the Company does not successfully commercialize any of its products or mitigate any of these other risks, it will be unable to generate revenue or achieve profitability. Basis of presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission for annual financial reporting. The Company’s reporting currency is the U.S. dollar. As of December 31, 2023, the Company had cash and cash equivalents of $142.1 million and an accumulated deficit of $176.6 million and the Company expects to incur losses for the foreseeable future. The Company expects that its cash and cash equivalents will be sufficient to fund current operations into the fourth quarter of 2025, without additional financing. The Company expects to seek additional funding through equity financing, government or private-party grants, debt financings or other capital sources, including collaborations with other companies or other strategic transactions. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or rights of the Company’s stockholders. If the Company is unable to obtain sufficient capital, the Company will be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or future commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. The consolidated financial statements have been prepared assuming the Company will continue as a going concern, which contemplates, among other things, the realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. Guarantees and indemnifications As permitted under the laws of England and Wales, the Company indemnifies its officers, directors, consultants and employees for certain events or occurrences that happen by reason of the relationship with, or position held at, the Company. Through the years ended December 31, 2023 and 2022, the Company had not experienced any losses related to these indemnification obligations, and no claims were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves were established. Use of estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue, income and expenses during the reporting period. The Company bases estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis, including those related to fair value of contingent consideration and impairment of goodwill and intangible assets. The Company’s actual results may differ from these estimates under different assumptions or conditions. As of the date of issuance of these consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgments or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the consolidated financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s financial statements.

Summary of Significant Accounting Policies - Share based compensation (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Expected dividend yield	0.00%	0.00%

Net (Loss)/Income Per Share - Additional Information (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Shares issuable for stock options that were excluded from the computation of diluted weighted-average shares outstanding (in shares)	6,207,664	2,912,756

Fair Value (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of financial instruments carried at fair value and classified within Level 3

The following table summarizes changes in the fair value of Contingent Consideration (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Beginning balance	$	1,711	$	2,371

Change in fair value recognized in net loss	55		(73)
Settlement of contingency	(163)		(325)
Foreign exchange translation recognized in other comprehensive loss	219		(262)
Ending balance	$	1,823	$	1,711

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In accordance with the terms of the Annual Increase of the Barinthus Biotherapeutics plc Share Award Plan 2021, the total number of ordinary shares available for issuance under the Plan increased by 4% of the Company’s issued and outstanding ordinary shares as of January 1, 2024. In January 2024, the Company granted a total of 1,592,423 share options to employees and directors with a weighted average exercise price of $3.70.

Summary of Significant Accounting Policies - Segment information (Details)	12 Months Ended
	Dec. 31, 2023 segment
Accounting Policies [Abstract]
Number of operating segments	1

Income Taxes - Components of income tax benefit (expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Deferred income tax benefit:
Total income tax benefit	$ 3,075	$ 4,471
United States
Current income tax benefit/(expense):
Foreign	(28)	133
Deferred income tax benefit:
Foreign	3,148	4,338
Other foreign
Current income tax benefit/(expense):
Foreign	$ (45)	$ 0

- Definition

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

+ References + Details

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

In-License Agreements

The Company is party to a number of licensing agreements, these agreements serve to provide the Company with the right to develop and exploit the counterparties’ intellectual property for certain medical indications. As part of execution of these arrangements, the Company paid certain upfront fees, which have been expensed as incurred because the developing technology has not yet reached technical feasibility, the lack of alternative use, and the lack of proof of potential value. The agreements cover a variety of fields, including influenza, cancer, HPV, HBV and MERS. The Company’s obligations for future payments under these arrangements are dependent on its ability to develop promising drug candidates, the potential market for these candidates and potential competing products, and the payment mechanisms in place in countries where the Company retains the right to sell. Each agreement provides for specific milestone payments, typically triggered by achievement of certain testing phases in human candidates, and future royalties ranging from 1 to 5% for direct sales of a covered product to 3 to 7% of net payments received for allowable sublicenses of technology developed by the Company. The obligation to make these payments is contingent upon the Company’s ability to develop candidates for submission for phased testing and approvals, and for the development of markets for the products developed by the Company. The Company has not made any material payments under these license agreements during the years ended December 31, 2023, and 2022.

Leases

The Company leases certain laboratory and office space under operating leases, which are described below.

The Oxford Science Park, Oxford

The Company leased an office and laboratory space from a related party in Oxford, England under an operating lease with a contractual term expiring in 2028. The lease was terminated on July 31, 2022, and the Company relocated its corporate headquarters to The Harwell Science and Innovation Campus, Oxfordshire, in the third quarter of 2022.

The Harwell Science and Innovation Campus, Oxfordshire

On September 3, 2021, the Company entered into a lease agreement for the lease of approximately 31,000 square feet in Harwell, Oxfordshire which expires in September 2031. The property is the Company’s corporate headquarters. As the Company’s leases typically do not provide an implicit rate, the Company uses an estimate of its incremental borrowing rate based on the information available at the lease commencement date, being the rate incurred to borrow on a collateralized basis over a similar term at an amount equal to the lease payments in a similar economic environment. The Company has provided the lessor with a refundable security deposit of $0.7 million which is included in Other assets.

Germantown, Maryland

On June 14, 2022, the Company entered into a lease agreement for the lease of approximately 19,700 square feet in Germantown, Maryland. The site will house the Company’s state-of-the-art wet laboratory in the United States of America. The lease expires on February 28, 2034, with the Company having a single right to extend for an additional five years on the same terms and conditions other than for the base rent. The Company has a rent-free period up to February 29, 2024 and is entitled to up to $3.5 million for leasehold improvements to the premises desired by the Company. The Company has provided the lessor with a refundable security deposit of $0.2 million which is included in Other assets.

The Company recorded a right-of-use asset and a lease liability on the effective date of the lease term. The Company’s right-of-use assets and lease liabilities are as follows (in thousands):


	December 31, 2023			December 31, 2022
Right-of-use asset	$	7,581		$	7,753
Lease liability, current	$	1,785		$	433
Lease liability, noncurrent	$	11,191		$	8,340

Other information
Operating cash flows from operating leases	$	639		$	1,081
Weighted average remaining lease term (years)	8.93			9.44
Weighted average discount rate	7.5		%	7.6		%

Lease Costs
Short-term lease costs	$	189		$	529
Fixed Lease Costs	$	883		$	1,216
Total lease cost	$	1,072		$	1,745

Maturities of the Company’s minimum lease liabilities as of December 31, 2023 were as follows (in thousands):


Maturity of lease liabilities:
2024	$	1,785
2025	1,936
2026	1,960
2027	1,985
2028	2,010
Thereafter	7,999
Total minimum lease payments	17,675
Less: imputed interest	(4,699)
Total lease liability	$	12,976

Non-lease and other costs paid to the lessors are primarily related to services provided by the lessors in operating the premises that includes fees, operating costs, taxes, and insurance related to the leased premises.

Other contingencies

The Company is a party in various contractual disputes, litigation, and potential claims arising in the ordinary course of business. The Company does not believe that the resolution of these matters will have a material adverse effect on its financial position or results of operations.

Income Taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$ 23,589	$ 9,940
Research and development credit carryforwards	40	3,146
Deferred revenue	0	54
Share based compensation	4,226	3,956
Lease liability	3,404	2,257
Accruals and intangibles	745	765
Capitalized Research and Development expenditure	4,228	2,522
Other	1	1
Gross deferred tax asset	36,233	22,641
Valuation allowance	(25,057)	(13,707)	$ (13,500)
Net deferred tax assets	11,176	8,934
Deferred tax liabilities:
Depreciation	(1,652)	(1,704)
Right-of-use lease asset	(1,922)	(1,993)
Unrealized gain on investment	(1,267)	(1,204)
Intangible assets	(6,909)	(7,779)
Net deferred tax liabilities	(11,750)	(12,680)
Total deferred tax, net	$ (574)	$ (3,746)

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Principles of consolidation

The accompanying consolidated financial statements include the accounts of Barinthus Biotherapeutics plc and those entities in which it has a controlling interest. Intercompany amounts are eliminated on consolidation. Amounts attributable to the noncontrolling interest are presented as a separate element of equity in the accompanying consolidated financial statements.

Comprehensive loss

Comprehensive loss for all periods presented is comprised primarily of net (loss)/income and other comprehensive loss, which solely relates to foreign currency translation adjustments.

Foreign currency translation

The Company’s reporting currency is the United States dollar. The functional currency of the parent and each subsidiary is the currency of the country and economic environment in which it is located. Assets and liabilities of each legal entity denominated or measured in a currency other than British Pounds are first translated into British pounds and consolidated. The consolidated balances are then converted into United States dollars at period-end exchange rates. Revenues and expenses are translated into British pounds, then into U.S. dollars at average exchange rates for each reporting period. Translation adjustments are reflected as accumulated other comprehensive loss within stockholders’ equity. Gains and losses on foreign currency transactions are included in the consolidated statements of operations and comprehensive loss in the general and administrative expenses. The aggregate net foreign exchange gain or loss included in determining net loss was a loss of $7.6 million and gain of $26.4 million for the years ended December 31, 2023 and 2022, respectively.

Segment information

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, the Company’s Chief Executive Officer, in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment, the research and development of immunotherapies and vaccines.

Noncontrolling interest

In 2018, Barinthus Biotherapeutics plc established VOLT with a related party. As of December 31, 2021, Barinthus Biotherapeutics plc had contributed cash and intellectual property with an aggregate value of $11.9 million for a 76% controlling interest. The related party had contributed cash and intellectual property with an aggregate value of $3.8 million for a 24% noncontrolling interest. There were no further contributions in the years ended December 31, 2023 and 2022. The contributed intellectual properties were initially recorded at investment date fair value by VOLT and immediately expensed as research and development costs. The Company accounts for the noncontrolling interest in the accompanying consolidated financial statements initially at fair value with the subsequent carrying value adjusted for the noncontrolling share of VOLT’s comprehensive loss.

Business Combinations

The Company accounts for business combinations using the acquisition method of accounting, which requires the recognition of tangible and identifiable intangible assets acquired and liabilities assumed at their estimated fair values as of the business combination date. The Company allocates any excess purchase price over the estimated fair value assigned to the net tangible and identifiable intangible assets acquired and liabilities assumed to goodwill. Contingent consideration is included within the acquisition cost and is recognized at its fair value on the acquisition date. A liability resulting from contingent consideration is remeasured to fair value at each reporting date until the contingency is resolved and changes in fair value are recognized in general and administrative expenses in the consolidated statements of operations and comprehensive loss. Transaction costs are expensed as incurred in general and administrative expenses. Results of operations and cash flows of acquired companies are included in the Company’s operating results from the date of acquisition.

Cash and cash equivalents

The Company considers all highly liquid investments purchased with remaining maturities of three months or less on the purchase date to be cash and cash equivalents. Cash and cash equivalents include bank demand deposits and money market funds that are actively traded (a Level 1 input). As of December 31, 2023, and 2022 there were no cash equivalents.

Revenue

The Company recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services.

The Company has entered into collaboration and license agreements, which are within the scope of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers, to discover, develop, manufacture and commercialize product candidates. The terms of these agreements typically contain multiple promises or obligations, which may include licenses, or options to obtain licenses, to product candidates or future product candidates. The Company also derives revenue from government grants.

Amounts received prior to revenue recognition are recorded as deferred revenue. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current portion of deferred revenue in the accompanying consolidated balance sheets. Amounts recognized as revenue, but not yet received or invoiced are generally recognized as accounts receivable.

License revenue

The Company’s arrangements may provide the collaboration partner with the right to select a target for licensing either at the inception of the arrangement or in the future. Under these arrangements, fees may be due to the Company (i) at the inception of the arrangement as an upfront fee or payment, (ii) upon the exercise of an option to acquire a license or (iii)

upon extending the selection period as an extension fee or payment. If an arrangement is determined to contain customer options that allow the customer to acquire additional goods or services, the goods and services underlying the customer options are not considered to be performance obligations at the outset of the arrangement, as they are contingent upon option exercise. The Company evaluates the customer options for material rights, or options to acquire additional goods or services for fee or at a discount. If the customer options are determined to represent a material right, the material right is recognized as a separate performance obligation at the inception of the arrangement. The Company allocates the transaction price to material rights based on the relative standalone selling price, which is determined based on the identified discount and the probability that the customer will exercise the option. Amounts allocated to a material right are not recognized as revenue until, at the earliest, the option is exercised or expires.

For arrangements that include sales-based milestones and royalties, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). This could require management to estimate the amount of revenue to recognize in the period if the actual data for the period has not been provided.

Research and development services

The promises under the Company’s collaboration and license agreements generally include research and development services to be performed by the Company on behalf of the collaboration partner. For performance obligations that include research and development services, the Company recognizes revenue allocated to such performance obligations based on an appropriate measure of progress. The Company utilizes judgment to determine the appropriate method of measuring progress for the purposes of recognizing revenue, which may include an input measure such as costs incurred during the reporting period or ratably over the service period. Reimbursements from the partner are evaluated as to whether the Company acts as a principal or an agent in such relationships. The Company evaluates whether control over the underlying goods or services were obtained prior to transferring these goods or services to the collaboration partner. Where the Company does not control the goods or services prior to transferring these goods or services to the collaboration partner, such reimbursements are presented net of costs. At the inception of each arrangement that includes development milestone payments in respect of development efforts, the Company evaluates whether the development milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated development milestone value is included in the transaction price. Development milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular development milestone in making this assessment. There is judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each reporting period, the Company reevaluates the probability of achievement of all development milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. If a milestone or other variable consideration relates specifically to the Company’s efforts to satisfy a single performance obligation or to a specific outcome from satisfying the performance obligation, the Company generally allocates the milestone amount entirely to that performance obligation once it is probable that a significant revenue reversal would not occur. To date, the Company has not recognized any development milestone revenue resulting from any of its arrangements.

Grant income

The Company receives certain grant income which support its research efforts in defined projects and include contributions towards the research and development costs. When there is reasonable assurance that the Company will comply with the conditions attached to a received grant, and when there is reasonable assurance that the grant will be received, grant income is recognized as other operating income on a gross basis in the consolidated statements of operations and comprehensive loss on a systematic basis over the periods in which the Company recognizes expenses for the related costs for which the grants are intended to compensate. Grant income may be subject to review by the grantor in periods subsequent to its recognition and may result in the reversal of grant income previously recognized. Payments received in advance of incurring reimbursable expenses are recorded as deferred income.

Concentrations of credit risk

Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash and cash equivalents and accounts receivable. Periodically, the Company maintains deposits in financial institutions in excess of government insured limits. Management believes that the Company is not exposed to significant credit risk as the Company’s deposits are held at financial institutions that management believes to be of high credit quality and the Company has not experienced any losses in these deposits. The Company’s standard payment terms are 30 days’.

The Company recognizes revenue earned in connection with the license and services provided to customers and grantors. The Company provides credit to the grantors in the normal course of providing such services based on evaluations of their financial condition and generally does not require collateral. To manage accounts receivable credit risk, the Company monitors the creditworthiness of its grantors. Historically, the Company has not experienced any credit losses related to accounts receivable and does not maintain allowances for uncollectible amounts.

Licensees and grantors that represented 10% of more of the Company’s revenue and accounted for 10% or more of accounts receivable are presented below:


Revenue	Country	Year ended December 31, 2023		Year ended December 31, 2022
Oxford University Innovation	U.K.	100	%	98	%


Accounts Receivable	Country	As of December 31, 2023		As of December 31, 2022
Oxford University Innovation	U.K.	—	%	94	%

Allowance for credit losses

The Company evaluates its cash equivalents and accounts receivable for expected credit losses. Expected credit losses represent the portion of the amortized cost basis of a financial asset that an entity does not expect to collect. An allowance for expected credit losses is meant to reflect a risk of loss even if remote, irrespective of the expectation of collection from a particular issuer or debt security. The Company has not historically experienced any credit losses on any of its financial assets. With respect to cash equivalents and accounts receivable, given consideration of their short maturity, historical losses and the current market environment, the Company concluded there are no expected credit losses for these financial assets.

Property and equipment

Property and equipment are stated at cost, net of accumulated depreciation. Expenditures for maintenance and repairs are charged to operating expenses as incurred, whereas major betterments are capitalized as additions to property and equipment. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:


Asset Category			Estimated Useful Life
Office furniture and equipment			3 years
Laboratory equipment			4 years
Leasehold improvements			Lesser of lease term or estimated useful lives

Intangible assets acquired through business combinations

Intangible assets consist of acquired developed technology. Intangible assets are stated at cost less accumulated amortization and impairment losses. Amortization is computed using the straight-line method over the estimated useful lives of the respective assets, which is 10 years.

Impairment of long-lived assets

The Company reviews long-lived assets to be held and used, including property and equipment, intangible assets and operating lease right-of-use assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets or asset group may not be recoverable. Evaluation of recoverability is first based on an estimate of undiscounted future cash flows resulting from the use of the asset or asset group and its eventual disposition. In the event such cash flows are not expected to be sufficient to recover the carrying amount of the asset or asset group, the assets are written down to their estimated fair values. No such impairments were recorded during the years ended December 31, 2023 and 2022.

Goodwill

Goodwill represents the excess of cost over the fair value of the net tangible and intangible assets of businesses acquired in a business combination. Goodwill is not amortized but rather is tested for impairment at least annually, or more frequently if events or changes in circumstances indicate that the carrying amount of goodwill may not be recoverable. The Company has elected to first assess the qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis of determining whether it is necessary to perform the quantitative goodwill impairment test. If the Company determines that it is more likely than not that its fair value is less than its carrying amount, then the quantitative goodwill impairment test will be performed. The quantitative goodwill impairment test identifies goodwill impairment and measures the amount of goodwill impairment loss to be recognized by comparing the fair value of a reporting unit with its carrying amount. If the fair value exceeds the carrying amount, no further analysis is required; otherwise, any excess of the goodwill carrying amount over the implied fair value is recognized as an impairment loss, and the carrying value of goodwill is written down to fair value. For the years ended December 31, 2023 and 2022, goodwill has been tested, and no impairments have been recorded.

Financial instruments

The Company’s financial instruments consist of cash and cash equivalents, accounts receivable, accounts payable, certain accrued expenses, contingent consideration and short-term debt. The carrying amounts of cash, cash equivalents, accounts receivable, security deposits, accounts payable, accrued expenses and short-term debt approximate their fair value due to the short-term nature of those financial instruments.

Fair value measurements

The Company follows the guidance in ASC 820, Fair Value Measurements and Disclosures, which defines fair value and establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below:

-Level 1 – Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.

-Level 2 – Valuations based on quoted prices in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

-Level 3 – Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

Fair value is a market-based measure considered from the perspective of a market participant rather than an entity-specific measure. Therefore, even when market assumptions are not readily available, the Company’s own assumptions are set to reflect those that market participants would use in pricing the asset or liability at the measurement date. The Company uses prices and inputs that are current as of the measurement date, including during periods of market dislocation. In periods of market dislocation, the observability of prices and inputs may change for many instruments. This condition could cause an

instrument to be reclassified within levels in the fair value hierarchy. There were no transfers within the fair value hierarchy during the years ended December 31, 2023 and 2022.

The Company recognizes a contingent consideration liability related to the acquisition of Avidea Technologies, Inc. The liability is remeasured to fair value at each reporting date until the contingency is resolved. The fair value of the contingent consideration is a Level 3 valuation determined using significant unobservable inputs being the probability of success of achievement of the milestones and the expected date of the milestone achievement. Changes in fair value are recognized in general and administrative expenses in the consolidated statements of operations and comprehensive loss.

Leases

Leases are accounted for under ASC 842, Leases (“ASC 842”) resulting in the recognition of lease liabilities and right-of-use assets. The Company only has operating leases. The Company has elected the practical expedient allowed under ASC 842 to account for each lease component (e.g., the right to use office space) and the associated non-lease components (e.g., maintenance services) as a single lease component. The Company also elected the short-term lease accounting policy for all asset classes; therefore, the Company is not recognizing a lease liability or right-of-use asset for any lease that, at the commencement date, has a lease term of 12 months or less and does not include an option to purchase the underlying asset that the Company is reasonably certain to exercise.

Variable lease payments such as the Company’s share of real estate taxes, utilities, and common area maintenance, are reported as non-lease operating expenses.

Right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Right-of-use assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As the Company’s leases typically do not provide an implicit rate, the Company uses an estimate of its incremental borrowing rate based on the information available at the lease commencement date in determining the present value of lease payments.

Right-of-use assets also include the effect of any lease payments made and exclude lease incentives. The lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized as part of total operating expenses on a straight-line basis over the lease term. The difference between the value of the right of use asset and lease liability is due to the reclassification of prepaid rent and unamortized lease incentives.

Research and development

Research and development costs are expensed as incurred on an accruals basis. Research and development costs include payroll and personnel expense (including share-based compensation), consulting costs, external contract research and development expenses, raw materials, drug product manufacturing costs, and allocated overheads including depreciation and amortization, facility costs, and utilities. Research and development costs that are paid in advance of performance are capitalized as a prepaid expense and amortized over the service period as the services are provided.

Clinical trial costs

Clinical trial costs are a component of research and development expenses. The Company accrues and expenses clinical trial activities performed by third parties based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activation, and other information provided to the Company by its vendors.

Patent and licensing costs

Patent and licensing costs are expensed as incurred because their realization is uncertain.

Ordinary shares

Ordinary shares are classified in stockholders’ equity and represent issued share capital.

Additional paid-in capital

Additional paid-in capital is classified in stockholders’ equity and represents the share premium account, where the difference between the price paid per share and the nominal value is recognized. The equity element of share based compensation is also recognized in additional paid in capital.

Share based compensation

The Company grants options over ordinary shares and restricted shares units to employees or Non-Executive Directors and accounts for share based compensation using the grant date fair value. Share based compensation awards are classified in the accompanying statements of operations based on the function to which the related services are provided. For service-based awards, compensation expense is generally recognized over the requisite service period of the awards, usually the vesting period. The Company applies the “multiple option” method of allocating expense. In applying this method, each vesting tranche of an award is treated as a separate grant and recognized on a straight-line basis over that tranche’s vesting period. For performance-based awards where the vesting of the awards may be accelerated upon the achievement of certain milestones, vesting and the related share-based compensation is recognized as an expense when it is probable the milestone will be met. Assumptions used in the option pricing model include the following:

Expected volatility. Previously there was insufficient trading history for the Company’s ordinary shares, therefore the expected price volatility for our ordinary shares was estimated using the average historical volatility of industry peers’ shares as of the grant date of our options over a period of history commensurate with the expected life of the options. When selecting industry peers used in measuring implied volatility, the Company considered the similarity of their products and business lines, as well as their stage of development, size and financial leverage. The Company applied this process consistently using the same or similar public companies until 2023. During 2023, the Company determined that there is sufficient historical information on volatility of its share price available and the expected volatility used in the fair value calculation of new option grants is calculated based on a blended volatility of both historical volatility of the Company's share price and the expected volatility of the average historical volatility of industry peers’ shares.

Expected term. The expected term of the Company’s share options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The “simplified” method was determined to be appropriate as the Company does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate expected term due to the limited period of time its equity shares have been publicly traded.

Risk-free interest rate. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods that are approximately equal to the expected term of the award.

Expected dividend. Expected dividend yield of zero is based on the fact that the Company has never paid cash dividends on ordinary shares and does not expect to pay any cash dividends in the foreseeable future.

The Company has elected to recognize the effect of forfeitures on share-based compensation when they occur. Any differences in compensation recognized at the time of forfeiture are recorded as a cumulative adjustment in the period where the forfeiture occurs.

When awards are modified, the Company compares the fair value of the affected award measured immediately prior to modification to its value after modification. To the extent that the fair value of the modified award exceeds the original award, the incremental fair value of the modified award is recognized as compensation on the date of modification for vested awards, and over the remaining vesting period for unvested awards.

Income taxes

The financial statements reflect provisions for income taxes in the United Kingdom and foreign jurisdictions. Deferred tax assets and liabilities represent future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities and for loss carryforwards using enacted tax rates expected to be in effect in the years in which the differences reverse. A valuation allowance is recorded when it is more likely than not that some or all of the deferred tax assets will not be realized.

The Company determines whether it is more likely than not that a tax position will be sustained upon examination. If it is not more likely than not that a position will be sustained, none of the benefit attributable to the position is recognized. The

tax benefit to be recognized for any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount that is more than 50% likely of being realized upon resolution of the contingency. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. To date, the Company has not incurred interest and penalties related to uncertain tax positions nor has it recorded any unrecognized tax benefits.

Research and development incentives

In the United Kingdom, the Company had previously been entitled to a research and development tax credit regime, being the Small and Medium-sized Enterprises R&D tax relief program, or SME Program, and, to the extent that our projects are grant funded or relate to work subcontracted to us by third parties, the Research and Development Expenditure Credit program, or RDEC Program. Until March 2023, under the SME program, the Company was able to surrender some of its trading losses that arise from qualifying research and development activities for a cash rebate of up to 33.35% of such qualifying research and development expenditure. Qualifying expenditures largely comprise employment costs for research staff, consumables, outsourced contract research organization costs and utilities costs incurred as part of research projects. Certain staff, consumables (including utilities), subcontractors and externally provided workers qualifying research and development expenditures are eligible for a cash rebate of up to 21.67%. A large portion of costs relating to research and development, clinical trials and manufacturing activities are eligible for inclusion within these tax credit cash rebate claims. From April 2023, under the SME program the additional deduction has decreased from 130% to 86%, the SME credit rate has reduced from 14.5% to 10% and the SME cash rebate for the Company has reduced from 33.35% to 18.6% and from 21.67% to 12.1% for subcontractors. Furthermore, the SME credit rate will decrease to 10% for expenditure incurred on or after April 1, 2023 unless the SME qualifies as an R&D intensive business i.e., R&D expenditure constitutes at least 40% (from April 1, 2023) or 30% (from accounting periods starting on or after April 1, 2024) of total expenditure. If the Company incurs tax losses, the Company is entitled to surrender the lesser of unrelieved tax loss sustained and the tax relief. As the realization of the tax relief does not depend on our generation of future taxable income or the Company’s ongoing tax status or tax position, the Company does not consider the tax relief as an element of income tax accounting under ASC 740, Income taxes and records the tax relief as a form of government grant or assistance. For the years ended December 31, 2023 and 2022, the Company recognized research and development incentives of $3.5 million and $1.2 million respectively.

Net (loss)/income per share

Basic net (loss)/income per share is computed by dividing the net (loss)/income attributable to ordinary shareholders by the weighted-average number of ordinary shares outstanding for the reporting period without consideration for potentially dilutive securities. Net (loss)/income attributable to ordinary shareholders is computed as if all net (loss)/income for the period had been distributed. During periods in which the Company incurred a net loss, the Company allocates no net loss to participating securities because they do not have a contractual obligation to share in the net loss of the Company.

The Company computes diluted net (loss)/income per ordinary share after giving consideration to all potentially dilutive ordinary equivalents, including stock options outstanding during the period, except where the effect of such non-participating securities would be antidilutive.

Diluted net (loss)/income per share is computed by dividing the net (loss)/income attributable to ordinary shareholders by the weighted-average number of ordinary shares and dilutive ordinary share equivalents outstanding for the period, determined using the treasury-stock and if-converted methods.

Contingent liabilities

A provision for contingent liabilities is recorded when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. With respect to legal matters, provisions are reviewed and adjusted to reflect the impact of negotiations, estimated settlements, legal rulings, advice of legal counsel and other information and events pertaining to a particular matter. The Company is a party to certain litigation and disputes arising in the normal course of business. As of December 31, 2023, the Company does not expect that such matters will have a material adverse effect on the Company’s business, financial position, results of operations, or cash flows.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by FASB or other standard setting bodies that the Company adopts as of the specified effective date. The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected not to “opt out” of the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different applications dates for public and nonpublic companies, the Company can adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and can do so until such time the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company.

Recently Issued Accounting Pronouncements

We have reviewed all recently issued standards and have determined that such standards will not have a material impact on our consolidated financial statements or do not otherwise apply to our current operations.

Income Taxes - Reconciliation to the effective tax rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Statutory tax rate	23.52%	19.00%
Increase (decreases) resulting from:
Permanent differences	1.03%	(103.46%)
Provision to return adjustments	(4.09%)	(105.66%)
Research and development credits	(4.94%)	(307.09%)
Foreign rate differential	1.23%	(149.82%)
Change in valuation allowance	(11.84%)	146.55%
Share based compensation	(0.84%)	(10.21%)
Effective tax rate	4.07%	(510.69%)

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of right-of-use, lease liabilities and other information

The Company’s right-of-use assets and lease liabilities are as follows (in thousands):


	December 31, 2023			December 31, 2022
Right-of-use asset	$	7,581		$	7,753
Lease liability, current	$	1,785		$	433
Lease liability, noncurrent	$	11,191		$	8,340

Other information
Operating cash flows from operating leases	$	639		$	1,081
Weighted average remaining lease term (years)	8.93			9.44
Weighted average discount rate	7.5		%	7.6		%

Lease Costs
Short-term lease costs	$	189		$	529
Fixed Lease Costs	$	883		$	1,216
Total lease cost	$	1,072		$	1,745

Schedule of maturities of minimum lease liabilities

Maturities of the Company’s minimum lease liabilities as of December 31, 2023 were as follows (in thousands):


Maturity of lease liabilities:
2024	$	1,785
2025	1,936
2026	1,960
2027	1,985
2028	2,010
Thereafter	7,999
Total minimum lease payments	17,675
Less: imputed interest	(4,699)
Total lease liability	$	12,976

Net (Loss)/Income Per Share - Computation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Numerator:
Net (loss)/income	$ (73,447)	$ 5,321
Net loss attributable to noncontrolling interest	100	21
Net (loss)/income attributable to Barinthus Biotherapeutics plc shareholders	$ (73,347)	$ 5,342
Denominator:
Weighted-average ordinary shares outstanding, basic (in shares)	38,386,491	37,248,126
Effect of dilutive stock options (in shares)	0	921,181
Weighted-average ordinary shares outstanding, diluted (in shares)	38,386,491	38,169,307
Net (loss)/income per share attributable to ordinary shareholders, basic (in usd per share)	$ (1.91)	$ 0.14
Net (loss)/income per share attributable to ordinary shareholders, diluted (in usd per share)	$ (1.91)	$ 0.14

Summary of Significant Accounting Policies - Concentrations of credit risk (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Concentration Risk [Line Items]
Standard payment terms	30 days
Revenue \| U.K. \| Oxford University Innovation
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	98.00%
Accounts Receivable \| U.K. \| Oxford University Innovation
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	94.00%

Foreign Currency Translation in General and Administrative Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Foreign Currency [Abstract]
Net foreign exchange gain (loss)	$ (7.6)	$ 26.4

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

(Loss) income before income taxes are as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
United Kingdom	$	(50,534)	$	15,511
United States	(24,507)		(14,648)
Other foreign	(1,481)		(13)
(Loss)/income before income taxes	$	(76,522)	$	850

The components of income tax benefit are as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Current income tax benefit/(expense):
United States	$	(28)	$	133
Other Foreign	(45)		—
Deferred income tax benefit:
United States	3,148		4,338
Total income tax benefit	$	3,075	$	4,471

A reconciliation of the UK statutory income tax rate to the Company's effective tax rate as reflected in the consolidated financial statements is as follows:


	Year ended December 31, 2023		Year ended December 31, 2022
Statutory tax rate	23.52	%	19.00	%
Increase (decreases) resulting from:
Permanent differences	1.03		(103.46)
Provision to return adjustments	(4.09)		(105.66)
Research and development credits	(4.94)		(307.09)
Foreign rate differential	1.23		(149.82)
Change in valuation allowance	(11.84)		146.55
Share based compensation	(0.84)		(10.21)

Effective tax rate	4.07	%	(510.69)	%

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income and for tax carryforwards. Significant components of the Company’s deferred tax assets and liabilities are as follows (in thousands):


	December 31, 2023		December 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$	23,589	$	9,940
Research and development credit carryforwards	40		3,146
Deferred revenue	—		54
Share based compensation	4,226		3,956
Lease liability	3,404		2,257
Accruals and intangibles	745		765
Capitalized Research and Development expenditure	4,228		2,522
Other	1		1
Gross deferred tax asset	36,233		22,641
Valuation allowance	(25,057)		(13,707)
Net deferred tax assets	11,176		8,934
Deferred tax liabilities:
Depreciation	(1,652)		(1,704)
Right-of-use lease asset	(1,922)		(1,993)
Unrealized gain on investment	(1,267)		(1,204)
Intangible assets	(6,909)		(7,779)
Net deferred tax liabilities	(11,750)		(12,680)
Total deferred tax, net	$	(574)	$	(3,746)

Specified research and experimentation costs under Section 174 of the Internal Revenue Code are required to be capitalized and amortized ratably over five years for domestic expenditures and over 15 years for foreign expenditures. This provision of Section 174 became effective for tax years beginning after December 31, 2021. As a result of the capitalization of these costs in the current year, the Company has recorded a $4.2 million deferred tax asset (2022: $2.5 million).

As of December 31, 2023, the Company had a valuation allowance of $25.1 million (2022: $13.7 million) against its deferred tax assets, which consisted principally of net operating loss and research and development credit carryforwards. The Company considered the positive and negative evidence bearing upon its ability to realize the deferred tax assets. In addition to the Company’s history of cumulative losses, the Company cannot be certain that future taxable income will be sufficient to realize its deferred tax assets. Accordingly, a valuation allowance has been provided against its deferred tax assets. When the Company changes its determination as to the amount of its deferred tax assets that can be realized, the valuation allowance is adjusted with a corresponding impact to the provision for income taxes in the period in which such determination is made.

Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2023 and 2022 related primarily to the increase in net operating loss and credit carryforwards, and were as follows:


	Year ended December 31, 2023		Year ended December 31, 2022
Valuations allowance at beginning of year	$	13,707	$	13,500
Changes in valuation allowance arising from in-year additions	1,052		—
Increases recorded to income tax provision	9,605		1,500
Foreign exchange translation	693		(1,293)
Valuation allowance at end of year	$	25,057	$	13,707

As of December 31, 2023, the Company had net operating loss ("NOL") carryforwards totaling approximately $92.7 million which have an unlimited carryforward period, of which $74.2 million originate in the United Kingdom. As of December 31, 2023, the Company had $0.04 million of research and development tax credit carryforwards which also have an unlimited carryforward period.

As of December 31, 2022, the Company had NOL carryforwards totaling approximately $39.6 million which have an unlimited carryforward period, of which $35.1 million originate in the United Kingdom. As of December 31, 2022, the Company had $3.1 million of research and development tax credit carryforwards which also have an unlimited carryforward period.

As of December 31, 2023 and 2022, the Company does not have any material unrecognized tax benefit liabilities. The Company files corporation/income tax returns in the United Kingdom, Australia, and the United States. The associated tax filings remain subject to examination by applicable tax authorities for a certain length of time following the tax year to which those filings relate. In the United Kingdom, tax years from 2020 remain subject to examination by HMRC. In all other jurisdictions, the tax years since inception remain subject to examination by the applicable taxing authorities as of December 31, 2023 and 2022.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Retirement Benefits [Abstract]
Employer contribution	$ 0.7	$ 0.5

Ordinary Shares - Additional Information (Details) £ / shares in Units, $ / shares in Units, $ in Thousands			12 Months Ended
	May 04, 2021 USD ($) shares	Apr. 21, 2021	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2023 vote £ / shares shares	Nov. 06, 2023 GBP (£)	Dec. 31, 2022 £ / shares shares	May 04, 2021 £ / shares shares	May 04, 2021 $ / shares shares
Ordinary Shares
Ordinary shares, authorized (in shares) \| shares					38,643,540		37,683,531
Ordinary shares, nominal value (in gbp per share) \| £ / shares					£ 0.000025		£ 0.000025
Proceeds from issue of ordinary shares, net of issuance costs			$ 2,035	$ 484
Number of votes per common share (in votes) \| vote					1
Percentage of ordinary shares present to exercise preemptive rights					75.00%
Maximum period to exercise preemptive rights			5 years
Maximum aggregate nominal amount of shares authorized to be allotted free from pre-emption rights \| £						£ 1,928
IPO
Ordinary Shares
Number of ADS shares closed (in shares) \| shares	6,500,000
Ordinary shares, authorized (in shares) \| shares								6,500,000	6,500,000
Ordinary shares, nominal value (in gbp per share) \| £ / shares								£ 0.000025
Ordinary shares, public offering price (in usd per share) \| $ / shares									$ 17.00
Proceeds from issue of ordinary shares, net of issuance costs	$ 102,800
Underwriting commissions	7,700
Offering costs	$ 2,200
Maximum period to exercise preemptive rights		5 years	5 years

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($)
$ in Thousands

Total

Total stockholders’ equity attributable to Barinthus Biotherapeutics plc stockholders

Ordinary Shares

Deferred Shares

Deferred A Shares

Deferred Shares

Deferred B Shares

Deferred Shares

Deferred C Shares

Additional Paid-in-capital

Accumulated Deficit

Accumulated Other Comprehensive Loss

Noncontrolling Interest

Beginning balance (in shares) at Dec. 31, 2021

37,188,730

63,443

570,987

27,828,231

Beginning balance at Dec. 31, 2021

$ 252,562

$ 252,125

$ 1

$ 86

$ 8

$ 0

^[1]

$ 369,103

$ (108,585)

$ (8,488)

$ 437

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Share based compensation

9,877

Issue of ordinary shares, net of issuance costs (in shares)

494,801

Issue of ordinary shares, net of issuance costs

484

$ 0

^[1]

484

Foreign currency translation adjustments

(25,083)

(24,972)

(111)

Measurement period and contingent consideration adjustments

Net (loss)/income

5,321

5,342

(21)

Ending balance (in shares) at Dec. 31, 2022

37,683,531

63,443

570,987

27,828,231

Ending balance at Dec. 31, 2022

243,201

242,896

$ 1

$ 86

$ 8

$ 0

^[1]

379,504

(103,243)

(33,460)

305

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Share based compensation

5,055

Issue of ordinary shares, net of issuance costs (in shares)

960,009

Issue of ordinary shares, net of issuance costs

2,035

$ 0

^[1]

2,035

Foreign currency translation adjustments

10,151

10,145

Cancellation of deferred shares (in shares)

(570,987)

(27,828,231)

Cancellation of deferred shares

$ (8)

Net (loss)/income

(73,447)

(73,347)

(100)

Ending balance (in shares) at Dec. 31, 2023

38,643,540

63,443

Ending balance at Dec. 31, 2023

$ 186,995

$ 186,784

$ 1

$ 86

$ 0

^[1]

$ 386,602

$ (176,590)

$ (23,315)

$ 211

[1]	Indicates amount less than one thousand

Summary of Significant Accounting Policies - Cash and cash equivalents (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Cash equivalents	$ 0.0	$ 0.0

Commitments and Contingencies - Right-of-use assets, lease liabilities and other information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Right-of-use asset	$ 7,581	$ 7,753
Lease liability, current	1,785	433
Lease liability, noncurrent	11,191	8,340
Other information
Operating cash flows from operating leases	$ 639	$ 1,081
Weighted average remaining lease term (years)	8 years 11 months 4 days	9 years 5 months 8 days
Weighted average discount rate	7.50%	7.60%
Lease Costs
Short-term lease costs	$ 189	$ 529
Fixed Lease Costs	883	1,216
Total lease cost	$ 1,072	$ 1,745

Intangible assets, net (Details) - USD ($) $ in Millions	12 Months Ended
Intangible assets, net (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Amortization expense for intangible assets	$ 3.2	$ 3.2
Estimated annual amortization expense for 2024	3.2
Estimated annual amortization expense for 2025	3.2
Estimated annual amortization expense for 2026	3.2
Estimated annual amortization expense for 2027	3.2
Estimated annual amortization expense for 2028	3.2
Estimated annual amortization expense for 2029	3.2
Estimated annual amortization expense for 2030	3.2
Estimated annual amortization expense for 2031	3.2
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross amount of amortizable intangible assets	31.6	31.6
Accumulated amortization for amortizable intangible assets	$ 6.5	$ 3.3

Income Taxes - Changes in the valuation allowance for deferred tax assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Valuation Allowance [Roll Forward]
Valuations allowance at beginning of year	$ 13,707	$ 13,500
Changes in valuation allowance arising from in-year additions	1,052	0
Increases recorded to income tax provision	9,605	1,500
Foreign exchange translation	693	(1,293)
Valuation allowance at end of year	$ 25,057	$ 13,707

Property and Equipment, Net - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 15,509	$ 9,279
Less: accumulated depreciation	(3,688)	(1,322)
Property and equipment, net	11,821	7,957
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	1,108	1,041
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	5,728	4,312
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 8,673	$ 3,926

Foreign Currency Translation in General and Administrative Expenses	12 Months Ended
	Dec. 31, 2023
Foreign Currency [Abstract]
Foreign Currency Translation in General and Administrative Expenses	Foreign Currency Translation in General and Administrative Expenses The aggregate, net foreign exchange gain or loss included in determining net (loss)/income recognized in general and administrative expenses for the year ended December 31, 2023, and 2022, was a loss of $7.6 million and a gain of $26.4 million, respectively.

- Definition

The entire disclosure for foreign currency transactions and translation. This may include description of foreign currency transactions, foreign currency gains and losses, explanation of change in cumulative translation adjustment, description of effect of subsequent foreign currency exchange rate change, cumulative translation adjustment movement, foreign currency translation adjustment by component movement, translation adjustment for net investment hedge movement, adjustment for long-term intercompany transactions, schedule of long-term intercompany balances and any other foreign currency transactions and translation related items.

+ References + Details

Out-licenses and Grants (Tables)

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Schedule of changes in contract liabilities

Changes in the contract liabilities during the years ended December 31, 2023 and 2022, are as follows (in thousands):


	December 31, 2023		December 31, 2022
Beginning balance	$	—	$	182
Revenue recognized related to contract liability balance	—		(158)
Foreign exchange translation	—		(24)
Ending balance	$	—	$	—

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Schedule of property and equipment, net

Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:


Asset Category			Estimated Useful Life
Office furniture and equipment			3 years
Laboratory equipment			4 years
Leasehold improvements			Lesser of lease term or estimated useful lives

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


	December 31, 2023		December 31, 2022
Office furniture and equipment	$	1,108	$	1,041
Laboratory equipment	5,728		4,312
Leasehold improvements	8,673		3,926
Property and equipment, at cost	15,509		9,279
Less: accumulated depreciation	(3,688)		(1,322)
Property and equipment, net	$	11,821	$	7,957

Summary of Significant Accounting Policies - Allowance for credit losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Expected credit losses for financial assets	$ 0.0	$ 0.0

Accrued Expenses and Other Current Liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Schedule of accrued expenses and other current liabilities

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


	December 31, 2023		December 31, 2022
Accrued manufacturing and clinical expenses	$	4,003	$	2,997

Accrued bonus	2,412		1,925
Accrued payroll and employee benefits	789		928
Accrued professional fees	942		1,270
Accrued other	1,066		941
Total	$	9,212	$	8,061

Out-licenses and Grants

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Out-licenses and Grants

OUI license

In April 2020, the Company entered into an Amendment, Assignment and Revenue Sharing Agreement (“License Agreement Amendment”) with Oxford University Innovation, or OUI, which vested and assigned all intellectual property rights in relation to any ChAdOx1 or ChAdOx2 vector-based vaccine jointly owned by the Company and OUI in order to facilitate the license of vaccines based on the ChAdOx1 by OUI to AstraZeneca plc (“AstraZeneca”). Under this agreement, the Company is entitled to receive from OUI a share of all payments received by OUI from AstraZeneca in respect of the vaccine based on the ChAdOx1. On December 30, 2020, AstraZeneca announced that vaccine based on the ChAdOx1 which we refer to as Vaxzevria had been approved for emergency supply in the United Kingdom by the United Kingdom Medicines and Healthcare products Regulatory Agency (MHRA).

The Company determined that the intellectual property vested and assigned under the License Agreement Amendment is a functional intellectual property (that is, it has significant standalone functionality in the form of its ability to treat a disease or condition) and there is no expectation under the License Agreement Amendment that the Company will undertake activities to change the functionality. Consequently, the Company concluded that the nature of the Company’s promise in transferring the intellectual property is to provide a right to use the Company’s functional intellectual property. Accordingly, the Company recognizes revenue in manner that depicts the Company’s progress toward satisfying its performance obligation of providing access to its intellectual property throughout the license period based on the terms of OUI’s agreement with AstraZeneca.

On March 28, 2022, pursuant to the OUI License Agreement Amendment, we were notified of the commencement of payments, arising from AstraZeneca’s commercial sales of Vaxzevria. Under the terms of an exclusive worldwide license agreement between OUI and AstraZeneca, OUI is entitled to milestone payments and royalties on commercial sales of Vaxzevria that began after the pandemic period. As part of the assignment from us to OUI, we are entitled to receive approximately 24% of payments received by OUI from AstraZeneca. For the year ended December 31, 2023, the Company recognized approximately $0.8 million as revenue (year ended December 31, 2022: $43.7 million) and had an outstanding receivable of nil as of December 31, 2023 (2022: $5.5 million). There is no guarantee that further payments will be received pursuant to the agreement in the future and, if such payments are made, that we will be notified of such payments in a timely manner.

Scancell contract

On November 2, 2022, the Company entered into an agreement with Scancell to grant a research and development license, consisting of upfront and development milestone and royalty payments, for the development and commercialization of the SNAPvax functional intellectual property. The Company recognized non-refundable upfront revenue, amounting to nil for the year ended December 31, 2023 (December 31, 2022: $0.7 million). As of December 31, 2023, nil was recorded as a receivable (December 31, 2022: $0.3 million).

Coalition for Epidemic Preparedness Innovations (“CEPI”) Funding Agreement

On December 20, 2023, Barinthus Biotherapeutics (UK) Limited (the “Company”), the Chancellors, Masters and Scholars of the University of Oxford (“Oxford,” together with the Company, the “Partners”) and the Coalition for Epidemic Preparedness Innovations (“CEPI”) entered into a Funding Agreement (the “Funding Agreement”) pursuant to which CEPI will provide funding of up to $34.8 million to the Company to advance the development of VTP-500, the Company’s vaccine candidate against Middle East Respiratory Syndrome (“MERS,” and such development activities, the “Project”). In December 2023, VTP-500 received PRIME (PRIority MEdicines) designation by the European Medicines Agency.

Pursuant to the Funding Agreement, the Company has agreed to pay CEPI on a country-by-country basis increasing mid-single digit percentage royalties of net sales and net income with respect to future cash sales of VTP-500, less certain deductions, for a period starting on December 20, 2023 (“Effective Date”) and ending the later of: (i) the expiration of the last valid patent claim included in intellectual property developed under the Project covering VTP-500 in such country, (ii) the expiration of Regulatory Exclusivity (as defined in the Funding Agreement) for VTP-500 in such country, and (iii) the tenth (10th) anniversary of the first commercial sale of VTP-500 (the “Royalty Term”). The Company shall also pay CEPI a mid-double digit percentage of net revenue earned on VTP-500 until CEPI has received payments from the Company under the Funding Agreement equaling the total amount of funding paid by CEPI to the Company and a low double-digit percentage of such net revenue thereafter. Sales for the benefit of end users in specified low and middle income countries

(“LMICs”) and upper and middle income countries (“UMICs”) are excluded from the calculations of net sales and net revenue. Sales of product for the benefit of end users in LMICs and UMICs are subject to tiered discounted pricing requirements under the Funding Agreement. The Company is further required to pay a mid-double digit percentage of any proceeds earned on any priority review voucher related to VTP-500 during the Royalty Period.

For the year ended December 31, 2023, no proceeds have been received and no income has been recognized in relation to this contract as no activities eligible for the funding were undertaken during the period.

Contract assets and liabilities

The Company discloses accounts receivable separately in the consolidated balance sheets at the net amount expected to be collected. Contract assets primarily relate to the Company’s conditional right to consideration for work completed but not billed at the reporting date. As of December 31, 2023 and 2022 the Company did not have any contract assets.

Contract liabilities primarily relate to payments received from customers in advance of performance under the contract and are disclosed as deferred revenue separately in the consolidated balance sheets. The Company’s contract liabilities arise when payment is received upfront for various multi-period extended license and service arrangements.

Changes in the contract liabilities during the years ended December 31, 2023 and 2022, are as follows (in thousands):


	December 31, 2023		December 31, 2022
Beginning balance	$	—	$	182
Revenue recognized related to contract liability balance	—		(158)
Foreign exchange translation	—		(24)
Ending balance	$	—	$	—

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
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-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued manufacturing and clinical expenses	$ 4,003	$ 2,997
Accrued bonus	2,412	1,925
Accrued payroll and employee benefits	789	928
Accrued professional fees	942	1,270
Accrued other	1,066	941
Total	$ 9,212	$ 8,061

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

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

Total revenue

$ 802

$ 44,703

Operating expenses

Research and development

44,874

42,350

General and administrative

39,842

6,394

Total operating expenses

84,716

48,744

Loss from operations

(83,914)

(4,041)

Other income /(expense):

Interest income

2,877

3,103

Interest expense

(28)

(19)

Research and development incentives

3,461

1,240

Other income, net

1,082

567

Total other income, net

7,392

4,891

(Loss)/profit before income tax

(76,522)

850

Tax benefit

3,075

4,471

Net (loss)/income

(73,447)

5,321

Net loss attributable to noncontrolling interest

100

Net (loss)/income attributable to Barinthus Biotherapeutics plc shareholders

$ (73,347)

$ 5,342

Weighted-average ordinary shares outstanding, basic (in shares)

38,386,491

37,248,126

Weighted-average ordinary shares outstanding, diluted (in shares)

38,386,491

38,169,307

Net (loss)/income per share attributable to ordinary shareholders, basic (in usd per share)

$ (1.91)

$ 0.14

Net (loss)/income per share attributable to ordinary shareholders, diluted (in usd per share)

$ (1.91)

$ 0.14

Net (loss)/income

$ (73,447)

$ 5,321

Other comprehensive gain/(loss) – foreign currency translation adjustments

10,151

(25,083)

Comprehensive loss

(63,296)

(19,762)

Comprehensive loss attributable to noncontrolling interest

132

Comprehensive loss attributable to Barinthus Biotherapeutics plc shareholders

(63,202)

(19,630)

License revenue

Total revenue

^[1]

802

44,694

Research grants and contracts

Total revenue

$ 0

$ 9

[1]	Includes license revenue from related parties for the year ended December 31, 2023 totaling $0.8 million (December 31, 2022: $43.7 million). License revenue is generated in the United Kingdom.

Prepaid and other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepayments and accrued income	$ 5,402	$ 5,887
Value Added Tax receivable	3,031	0
Lease incentives receivable	0	1,770
Other	1,474	611
Total	$ 9,907	$ 8,268

Summary of Significant Accounting Policies - Foreign currency translation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Net foreign exchange gain (loss)	$ (7.6)	$ 26.4

Net (Loss)/Income Per Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Schedule of computation of basic and diluted net (loss)/income per share

The following table sets forth the computation of basic and diluted net (loss)/income per share for the years ended December 31, 2023 and 2022 (in thousands, except number of shares and per share amounts):


	Year Ended December 31,
Numerator:	December 31, 2023		December 31, 2022
Net (loss)/income	$	(73,447)	$	5,321
Net loss attributable to noncontrolling interest	100		21
Net (loss)/income attributable to Barinthus Biotherapeutics plc shareholders	$	(73,347)	$	5,342
Denominator:
Weighted-average ordinary shares outstanding, basic	38,386,491		37,248,126
Effect of dilutive stock options	—		921,181
Weighted-average ordinary shares outstanding, diluted	38,386,491		38,169,307
Net (loss)/income per share attributable to ordinary shareholders, basic	$	(1.91)	$	0.14
Net (loss)/income per share attributable to ordinary shareholders, diluted	$	(1.91)	$	0.14

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Guarantees and indemnifications

As permitted under the laws of England and Wales, the Company indemnifies its officers, directors, consultants and employees for certain events or occurrences that happen by reason of the relationship with, or position held at, the Company.

Use of estimates

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue, income and expenses during the reporting period. The Company bases estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis, including those related to fair value of contingent consideration and impairment of goodwill and intangible assets. The Company’s actual results may differ from these estimates under different assumptions or conditions.

As of the date of issuance of these consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgments or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the consolidated financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s financial statements.

Principles of consolidation

Comprehensive loss

Comprehensive loss for all periods presented is comprised primarily of net (loss)/income and other comprehensive loss, which solely relates to foreign currency translation adjustments.

Foreign currency translation

Segment information

Noncontrolling interest

Business combinations

Business Combinations

Cash and cash equivalents

Revenue

License revenue

Research and development services

Grant Income

Grant income

Concentrations of credit risk

Allowance for credit losses

Property and equipment


Asset Category			Estimated Useful Life
Office furniture and equipment			3 years
Laboratory equipment			4 years
Leasehold improvements			Lesser of lease term or estimated useful lives

Intangible assets acquired through business combinations

Impairment of long-lived assets

Goodwill

Financial instruments

Fair value measurements

-Level 1 – Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.

-Level 2 – Valuations based on quoted prices in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

-Level 3 – Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

instrument to be reclassified within levels in the fair value hierarchy. There were no transfers within the fair value hierarchy during the years ended December 31, 2023 and 2022.

Leases

Variable lease payments such as the Company’s share of real estate taxes, utilities, and common area maintenance, are reported as non-lease operating expenses.

Research and development

Clinical trial costs

Patent and licensing costs

Patent and licensing costs are expensed as incurred because their realization is uncertain.

Ordinary shares

Ordinary shares are classified in stockholders’ equity and represent issued share capital.

Additional paid-in capital

Share based compensation

Income taxes

Research and development incentives

Net (loss)/income per share

Contingent liabilities

Recent Accounting Pronouncements

Recently Issued Accounting Pronouncements

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

12 Months Ended

Dec. 31, 2023

Dec. 31, 2022

CASH FLOWS FROM OPERATING ACTIVITIES:

Net (loss)/income

$ (73,447)

$ 5,321

Adjustments to reconcile net (loss)/income to net cash used in operating activities:

Share based compensation

5,055

9,877

Depreciation and amortization

5,429

4,323

Non-cash lease expenses

1,328

1,216

Unrealized foreign exchange loss/(gain)

7,531

(24,905)

Change in contingent consideration

(73)

Non cash interest expense

Deferred tax expense

(3,075)

(4,337)

Profit on sale of property and equipment

(348)

Changes in operating assets and liabilities:

Accounts receivable (including related parties)

5,800

(5,833)

Prepaid expenses and other current assets

2,200

(2,170)

Research and development incentives receivable

(127)

1,158

Accounts payable

(3,378)

1,140

Accrued expenses and other current liabilities

1,993

751

Deferred revenue

(183)

Operating lease liabilities

(445)

Other assets

128

(387)

Net cash used in operating activities

(50,925)

(14,431)

CASH FLOWS FROM INVESTING ACTIVITIES:

Proceeds from sale of property and equipment

388

Purchases of property and equipment

(5,413)

(6,138)

Net cash used in investing activities

(5,413)

(5,750)

CASH FLOWS FROM FINANCING ACTIVITIES:

Issue of shares from the exercise of stock options

^[1]

Proceeds from issue of ordinary shares, net of issuance costs

2,035

484

Payment of contingent consideration

(163)

Repayment of debt

(159)

Net cash provided by financing activities

1,872

325

Effect of exchange rates on cash and cash equivalents

2,171

187

Net decrease in cash and cash equivalents

(52,295)

(19,669)

Cash and cash equivalents, beginning of the year

194,385

214,054

Cash and cash equivalents, end of the year

142,090

194,385

Supplemental cash flow disclosures:

Cash paid for interest

^[1]

Cash paid for income taxes

^[1]

Non-Cash investing and financing activities

Purchases of property and equipment included in accounts payable and accrued liabilities

559

ROU assets obtained in exchange for operating lease liabilities

2,400

Asset retirement obligation

287

999

Changes to right-of-use asset resulting from lease reassessment event

(207)

Measurement period adjustments

(38)

Contingent Consideration settled in equity

$ 0

$ 78

[1]	Indicates amount less than one thousand

Out-licenses and Grants - Additional Information (Details) - USD ($)
$ in Thousands

12 Months Ended

Dec. 20, 2023

Mar. 28, 2022

Dec. 31, 2023

Dec. 31, 2022

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Revenue recognized

$ 802

$ 44,703

Non-refundable upfront revenue recognized

158

License revenue

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Revenue recognized

^[1]

802

44,694

OUI

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Percentage of royalties on commercial sales

24.00%

Agreement with OUI

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Accounts receivable

5,500

Agreement with OUI | License revenue

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Revenue recognized

800

43,700

Agreement with Scancell

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Accounts receivable

300

Non-refundable upfront revenue recognized

$ 700

CEPI Funding Agreement

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Maximum funding amount

$ 34,800

Maximum royalty payment period

10 years

Proceeds from grants received

Income recognized

$ 0

[1]	Includes license revenue from related parties for the year ended December 31, 2023 totaling $0.8 million (December 31, 2022: $43.7 million). License revenue is generated in the United Kingdom.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Schedule of concentration of credit risk

Licensees and grantors that represented 10% of more of the Company’s revenue and accounted for 10% or more of accounts receivable are presented below:


Revenue	Country	Year ended December 31, 2023		Year ended December 31, 2022
Oxford University Innovation	U.K.	100	%	98	%


Accounts Receivable	Country	As of December 31, 2023		As of December 31, 2022
Oxford University Innovation	U.K.	—	%	94	%

Schedule of property and equipment

Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:


Asset Category			Estimated Useful Life
Office furniture and equipment			3 years
Laboratory equipment			4 years
Leasehold improvements			Lesser of lease term or estimated useful lives

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


	December 31, 2023		December 31, 2022
Office furniture and equipment	$	1,108	$	1,041
Laboratory equipment	5,728		4,312
Leasehold improvements	8,673		3,926
Property and equipment, at cost	15,509		9,279
Less: accumulated depreciation	(3,688)		(1,322)
Property and equipment, net	$	11,821	$	7,957

Goodwill

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

The following table summarizes changes in goodwill (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Beginning balance	$	12,209	$	12,630
Measurement period adjustments	—		(421)
Ending balance	$	12,209	$	12,209

Fair Value

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value

The Company’s financial instruments consist of cash and cash equivalents, accounts receivable, accounts payable, certain accrued expenses, contingent consideration and short-term debt. The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, certain accrued expenses, contingent consideration and short-term debt approximated their respective fair value due to the short-term nature and maturity of these instruments.

As of December 31, 2023, the Company had a contingent consideration liability of $1.8 million related to the acquisition of Avidea Technologies, Inc. The fair value of the contingent consideration is a Level 3 valuation with the significant

unobservable inputs being the probability of success of achievement of the milestones and the expected date of the milestone achievement. Significant judgment is employed in determining the appropriateness of certain of these inputs.

The following table summarizes changes in the fair value of Contingent Consideration (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Beginning balance	$	1,711	$	2,371

Change in fair value recognized in net loss	55		(73)
Settlement of contingency	(163)		(325)
Foreign exchange translation recognized in other comprehensive loss	219		(262)
Ending balance	$	1,823	$	1,711

- 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

Share-Based Compensation - Share based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share based compensation expense	$ 5,055	$ 9,877
Research and development
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share based compensation expense	2,011	2,668
General and administrative
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share based compensation expense	$ 3,044	$ 7,209

- 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
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 1D
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480483/718-10-35-1D

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-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(v)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

+ Details

Share-Based Compensation - Weighted-average assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Enterprise Management Incentive Share Option Scheme
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected volatility	97.10%	94.70%
Expected term (years)	6 years	6 years
Risk-free interest rate	3.70%	2.40%
Expected dividend yield	0.00%	0.00%

- Definition

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

+ References

+ Details

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Deferred tax assets for capitalized research and development expenditure	$ 2,522	$ 4,228
Valuation allowance	13,707	25,057	$ 13,500
Net operating loss carryforwards	39,600	92,700
Research and development tax credit carryforwards	3,100	40
Unlimited carryforward amount	$ 35,100
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		$ 74,200

Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Beginning balance	$ 12,209	$ 12,630
Measurement period adjustments	0	(421)
Ending balance	$ 12,209	$ 12,209

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2023	Mar. 14, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-40367
Entity Registrant Name	BARINTHUS BIOTHERAPEUTICS PLC
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	Unit 6-10, Zeus Building
Entity Address, Address Line Two	Rutherford Avenue
Entity Address, City or Town	Harwell,Didcot
Entity Address, Postal Zip Code	OX11 0DF
Entity Address, Country	GB
City Area Code	+44 (0)
Local Phone Number	1865 818 808
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
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
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 79.4
Entity Common Stock, Shares Outstanding		38,921,212
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission relative to the registrant’s 2024 Annual Meeting of Shareholders are incorporated by reference into Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K.
Entity Central Index Key	0001828185
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Ordinary shares
Document Information [Line Items]
Title of 12(b) Security	Ordinary shares, nominal value £0.000025 per share
American Depositary Shares
Document Information [Line Items]
Title of 12(b) Security	American Depositary Shares
Trading Symbol	BRNS
Security Exchange Name	NASDAQ

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of (loss) income before income taxes

(Loss) income before income taxes are as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
United Kingdom	$	(50,534)	$	15,511
United States	(24,507)		(14,648)
Other foreign	(1,481)		(13)
(Loss)/income before income taxes	$	(76,522)	$	850

Summary of components of income tax benefit (expense)

The components of income tax benefit are as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Current income tax benefit/(expense):
United States	$	(28)	$	133
Other Foreign	(45)		—
Deferred income tax benefit:
United States	3,148		4,338
Total income tax benefit	$	3,075	$	4,471

Reconciliation to the effective tax rate

A reconciliation of the UK statutory income tax rate to the Company's effective tax rate as reflected in the consolidated financial statements is as follows:


	Year ended December 31, 2023		Year ended December 31, 2022
Statutory tax rate	23.52	%	19.00	%
Increase (decreases) resulting from:
Permanent differences	1.03		(103.46)
Provision to return adjustments	(4.09)		(105.66)
Research and development credits	(4.94)		(307.09)
Foreign rate differential	1.23		(149.82)
Change in valuation allowance	(11.84)		146.55
Share based compensation	(0.84)		(10.21)

Effective tax rate	4.07	%	(510.69)	%

Summary of significant components of deferred tax assets and liabilities

Significant components of the Company’s deferred tax assets and liabilities are as follows (in thousands):


	December 31, 2023		December 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$	23,589	$	9,940
Research and development credit carryforwards	40		3,146
Deferred revenue	—		54
Share based compensation	4,226		3,956
Lease liability	3,404		2,257
Accruals and intangibles	745		765
Capitalized Research and Development expenditure	4,228		2,522
Other	1		1
Gross deferred tax asset	36,233		22,641
Valuation allowance	(25,057)		(13,707)
Net deferred tax assets	11,176		8,934
Deferred tax liabilities:
Depreciation	(1,652)		(1,704)
Right-of-use lease asset	(1,922)		(1,993)
Unrealized gain on investment	(1,267)		(1,204)
Intangible assets	(6,909)		(7,779)
Net deferred tax liabilities	(11,750)		(12,680)
Total deferred tax, net	$	(574)	$	(3,746)

Summary of changes in the valuation allowance for deferred tax assets


	Year ended December 31, 2023		Year ended December 31, 2022
Valuations allowance at beginning of year	$	13,707	$	13,500
Changes in valuation allowance arising from in-year additions	1,052		—
Increases recorded to income tax provision	9,605		1,500
Foreign exchange translation	693		(1,293)
Valuation allowance at end of year	$	25,057	$	13,707

CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands

Dec. 31, 2023

Dec. 31, 2022

ASSETS

Cash and cash equivalents

$ 142,090

$ 194,385

Research and development incentives receivable

4,908

4,541

Prepaid expenses and other current assets

9,907

8,268

Total current assets

156,905

213,041

Goodwill

12,209

Property and equipment, net

11,821

7,957

Intangible assets, net

25,108

28,269

Right of use assets, net

7,581

7,753

Other assets

882

976

Total assets

214,506

270,205

Current liabilities:

Accounts payable

1,601

3,748

Accrued expenses and other current liabilities

9,212

8,061

Operating lease liability - current

1,785

433

Total current liabilities

12,598

12,242

Non-Current liabilities:

Operating lease liability - non-current

11,191

8,340

Contingent consideration

1,823

1,711

Other non-current liabilities

1,325

965

Deferred tax liability, net

574

3,746

Total liabilities

27,511

27,004

Commitments and contingencies (Note 16)

Stockholders’ equity:

Ordinary shares, £0.000025 nominal value; 38,643,540 shares authorized, issued and outstanding (December 31, 2022: authorized, issued and outstanding: 37,683,531)

Additional paid-in capital

386,602

379,504

Accumulated deficit

(176,590)

(103,243)

Accumulated other comprehensive loss – foreign currency translation adjustments

(23,315)

(33,460)

Total stockholders’ equity attributable to Barinthus Biotherapeutics plc shareholders

186,784

242,896

Noncontrolling interest

211

305

Total stockholders’ equity

186,995

243,201

Total liabilities and stockholders’ equity

214,506

270,205

Deferred A shares

Stockholders’ equity:

Deferred shares

Deferred B shares

Stockholders’ equity:

Deferred shares

Deferred C shares

Stockholders’ equity:

^[1]

ASSETS

323

ASSETS

$ 0

$ 5,524

[1]	Indicates amount less than one thousand

Summary of Significant Accounting Policies - Noncontrolling interest (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related parties
Noncontrolling Interest [Line Items]
Cumulative contributions from noncontrolling interest owner			$ 3.8
VOLT
Noncontrolling Interest [Line Items]
Cumulative contributions from controlling interest owner			$ 11.9
Contributions to acquire additional interest in subsidiaries	$ 0.0	$ 0.0
VOLT
Noncontrolling Interest [Line Items]
Controlling interest (as a percent)			76.00%
VOLT \| Related parties
Noncontrolling Interest [Line Items]
Noncontrolling interest (as a percent)			24.00%

CONSOLIDATED BALANCE SHEETS (Parenthetical) - £ / shares	Dec. 31, 2023	Dec. 31, 2022
Ordinary shares, nominal value (in gbp per share)	£ 0.000025	£ 0.000025
Ordinary shares, authorized (in shares)	38,643,540	37,683,531
Ordinary shares, issued (in shares)	38,643,540	37,683,531
Ordinary shares, outstanding (in shares)	38,643,540	37,683,531
Deferred A shares
Deferred shares, nominal value (in gbp per share)	£ 1	£ 1
Deferred shares, authorized (in shares)	63,443	63,443
Deferred shares, issued (in shares)	63,443	63,443
Deferred shares, outstanding (in shares)	63,443	63,443
Deferred B shares
Deferred shares, nominal value (in gbp per share)	£ 0.01	£ 0.01
Deferred shares, authorized (in shares)	0	570,987
Deferred shares, issued (in shares)	0	570,987
Deferred shares, outstanding (in shares)	0	570,987
Deferred C shares
Deferred shares, nominal value (in gbp per share)	£ 0.000007	£ 0.000007
Deferred shares, authorized (in shares)	0	27,828,231
Deferred shares, issued (in shares)	0	27,828,231
Deferred shares, outstanding (in shares)	0	27,828,231

Income Taxes - (Loss) income before income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
United Kingdom	$ (50,534)	$ 15,511
(Loss)/profit before income tax	(76,522)	850
United States
Income Taxes [Line Items]
Foreign	(24,507)	(14,648)
Other foreign
Income Taxes [Line Items]
Foreign	$ (1,481)	$ (13)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(11))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479557/942-235-S99-1

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 940
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-URI https://asc.fasb.org//1943274/2147481913/940-20-25-1

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Subsequent Events (Details) - $ / shares		1 Months Ended	12 Months Ended
Subsequent Events (Details) - $ / shares	Jan. 01, 2024	Jan. 31, 2024	Dec. 31, 2023
Subsequent Event
Number of options granted (in shares)			2,288,236
Weighted average exercise price of options granted (in usd per share)			$ 2.51
Subsequent Event \| Stock options
Subsequent Event
Number of options granted (in shares)		1,592,423
Weighted average exercise price of options granted (in usd per share)		$ 3.70
Subsequent Event \| Barinthus Biotherapeutics plc Share Award Plan 2021
Subsequent Event
Percentage of issued and outstanding ordinary shares available for issuance	4.00%

Summary of Significant Accounting Policies - Impairment of long-lived assets and Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Impairment of long-lived assets	$ 0	$ 0
Impairment of goodwill	$ 0	$ 0

Share-Based Compensation - Summary of stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Stock Options
Outstanding at the beginning of the period (in shares)	4,884,720
Granted (in shares)	2,288,236
Exercised (in shares)	(72,386)
Forfeited/expired (in shares)	(892,906)
Outstanding at the end of the period (in shares)	6,207,664	4,884,720
Exercisable at the end of the period (in shares)	2,839,791
Weighted- average Exercise Price Per Option
Outstanding at the beginning of the period (in usd per share)	$ 9.04
Granted (in usd per share)	2.51
Exercised (in usd per share)	0.00026
Forfeited/expired (in usd per share)	7.30
Outstanding at the end of the period (in usd per share)	6.91	$ 9.04
Exercisable at the end of the period (in usd per share)	$ 8.91
Additional Disclosures
Outstanding, Weighted-average remaining contractual term (Years)	7 years 11 months 12 days	7 years 4 months 9 days
Exercisable, Weighted-average remaining contractual term (Years) (in years)	7 years 3 months 29 days
Outstanding, Aggregate Intrinsic Value	$ 6,044	$ 2,619
Exercisable, Aggregate Intrinsic Value	$ 2,883

Net (Loss)/Income Per Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Net (Loss)/Income Per Share


	Year Ended December 31,
Numerator:	December 31, 2023		December 31, 2022
Net (loss)/income	$	(73,447)	$	5,321
Net loss attributable to noncontrolling interest	100		21
Net (loss)/income attributable to Barinthus Biotherapeutics plc shareholders	$	(73,347)	$	5,342
Denominator:
Weighted-average ordinary shares outstanding, basic	38,386,491		37,248,126
Effect of dilutive stock options	—		921,181
Weighted-average ordinary shares outstanding, diluted	38,386,491		38,169,307
Net (loss)/income per share attributable to ordinary shareholders, basic	$	(1.91)	$	0.14
Net (loss)/income per share attributable to ordinary shareholders, diluted	$	(1.91)	$	0.14

Since the Company was in a loss position for 2023, basic net loss per share is the same as diluted net loss per share, as the inclusion of all potential ordinary share equivalents outstanding would have been anti-dilutive. For the year ended December 31, 2023, 6,207,664 potential ordinary shares issuable for stock options were excluded from the computation of diluted weighted-average shares outstanding because including them would have had an anti-dilutive effect. For the year ended December 31, 2022, 2,912,756 potential ordinary shares issuable for stock options, respectively, were excluded from the computation of diluted weighted-average shares outstanding because including them would have had an anti-dilutive effect.

Summary of Significant Accounting Policies - Research and Development Incentives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Research and development incentives	$ 3,461	$ 1,240

Fair Value - Additional information (Details) $ in Millions	Dec. 31, 2023 USD ($)
Avidea
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Contingent consideration liability	$ 1.8

Accrued Expenses and Other Current Liabilities

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

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


	December 31, 2023		December 31, 2022
Accrued manufacturing and clinical expenses	$	4,003	$	2,997

Accrued bonus	2,412		1,925
Accrued payroll and employee benefits	789		928
Accrued professional fees	942		1,270
Accrued other	1,066		941
Total	$	9,212	$	8,061

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2.3	$ 1.1

Out-licenses and Grants - Changes in the contract liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Contract with Customer, Liability [Roll Forward]
Beginning balance	$ 0	$ 182
Revenue recognized related to contract liability balance	0	(158)
Foreign exchange translation	0	(24)
Ending balance	$ 0	$ 0

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2023
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions During the year ended December 31, 2023, the Company incurred expenses of $0.4 million (December 31, 2022: $0.4 million) from its shareholder, the University of Oxford, related to clinical study costs. As of December 31, 2023, the Company owed nil (2022: $nil). During the year ended December 31, 2023, the Company incurred expenses of $0.6 million (December 31, 2022: $0.4 million) from Oxford University Innovation Limited which is a wholly owned subsidiary of the Company’s shareholder, the University of Oxford. As of December 31, 2023, the Company owed $2 thousand (December 31, 2022: nil) to Oxford University Innovation Limited. During the year ended December 31, 2023, the Company recognized license revenue of $0.8 million (December 31, 2022: $43.7 million) from Oxford University Innovation Limited which is a wholly owned subsidiary of the Company’s shareholder, the University of Oxford. As of December 31, 2023, the Company was owed nil (2022: $5.5 million) from Oxford University Innovation Limited.

- 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
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-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))
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-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-URI https://asc.fasb.org//1943274/2147483326/850-10-50-6

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

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-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 - Maturities of minimum lease liabilities (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2024	$ 1,785
2025	1,936
2026	1,960
2027	1,985
2028	2,010
Thereafter	7,999
Total minimum lease payments	17,675
Less: imputed interest	(4,699)
Total lease liability	$ 12,976

Goodwill (Tables)

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of goodwill

The following table summarizes changes in goodwill (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Beginning balance	$	12,209	$	12,630
Measurement period adjustments	—		(421)
Ending balance	$	12,209	$	12,209

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
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-Paragraph 1
-Subparagraph (h)
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Name Accounting Standards Codification
-Section 50
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Section 50
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-Publisher FASB
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Name Accounting Standards Codification
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Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-2

+ Details

Commitments and Contingencies - Additional information (Details) $ in Millions			12 Months Ended
	Jun. 14, 2022 USD ($) ft²	Sep. 03, 2021 USD ($) ft²	Dec. 31, 2023
Oxfordshire
Other Commitments [Line Items]
Size of space under lease agreement (in square feet) \| ft²		31,000
Refundable security deposit		$ 0.7
Maryland
Other Commitments [Line Items]
Size of space under lease agreement (in square feet) \| ft²	19,700
Refundable security deposit	$ 0.2
Additional lease term	5 years
Leasehold improvement expense	$ 3.5
In-License Agreements \| Minimum
Other Commitments [Line Items]
Percentage of future royalties for direct sales of a covered product			1.00%
Net payments received for allowable sublicenses of technology developed			3.00%
In-License Agreements \| Maximum
Other Commitments [Line Items]
Percentage of future royalties for direct sales of a covered product			5.00%
Net payments received for allowable sublicenses of technology developed			7.00%

Property and Equipment, Net

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

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


	December 31, 2023		December 31, 2022
Office furniture and equipment	$	1,108	$	1,041
Laboratory equipment	5,728		4,312
Leasehold improvements	8,673		3,926
Property and equipment, at cost	15,509		9,279
Less: accumulated depreciation	(3,688)		(1,322)
Property and equipment, net	$	11,821	$	7,957

Depreciation expense for the year ended December 31, 2023 was $2.3 million (December 31, 2022: $1.1 million).

Intangible assets, net	12 Months Ended
Intangible assets, net	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, net	Intangible assets, net The gross amount of amortizable intangible assets, consisting of acquired developed technology, was $31.6 million at both December 31, 2023 and 2022 and accumulated amortization was $6.5 million and $3.3 million as of December 31, 2023 and 2022, respectively. The amortization expense for the year ended December 31, 2023 was $3.2 million (December 31, 2022: $3.2 million). The estimated annual amortization expense is $3.2 million for the years 2024 through to 2031.

Share-Based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Share-Based Compensation

On April 8, 2021, the Board of the Company adopted the Barinthus Biotherapeutics plc Share Award Plan 2021 (“the Plan”) and the Barinthus Biotherapeutics plc Non-Employee Sub-Plan which is a sub-plan of the Plan. Under the terms of the Plan, the Board is permitted to grant awards to employees as restricted share units, options, share appreciation rights and restricted shares. The aggregate number of shares initially available for issuance under the Plan and the Barinthus Biotherapeutics plc Non-Employee Sub-Plan cannot exceed 3,675,680 ordinary shares (the “Initial Limit”). Beginning calendar year 2023, the total number of ordinary shares available for issuance under the Plan shall be increased on January 1 of each year in an amount equal to the lesser of (i) 4% of the Company’s issued and outstanding ordinary shares (which 4% limit shall be measured as of January 1 of such year) and (ii) such number of ordinary shares as determined by the Compensation Committee of the Board in its discretion (the “Annual Increase”). In accordance with the terms of the Annual Increase, the total number of ordinary shares available for issuance under the Plan increased by 1,507,341 of January 1, 2023. The awards generally vest based on the grantee’s continued service with the Company during a specified period following grant as determined by the Board and generally expire ten years from the grant date. Option awards generally vest over three years, but vesting conditions can vary at the discretion of the Company’s Board. As of December 31, 2023 and 2022, 1,623,840 and 1,670,268 ordinary shares are available for future grants, respectively.

In 2018, the Company’s board of directors adopted the Enterprise Management Incentive Share Option Scheme (the “EMI Plan”) which provided for the grant of incentive stock options and nonqualified stock options to non-director employees of the Company. The Company also has a nonqualified stock option plan for officers and directors. The awards generally vest based on the grantee’s continued service with the Company during a specified period following grant as determined by the board of directors and generally expire ten years from the grant date. Option awards generally vest over three years, but vesting conditions can vary at the discretion of the Company’s board of directors. A total of 3,530,634 ordinary shares were reserved for issuance in accordance with the provisions of the EMI Plan and restricted stock unit (“RSUs”) plan. Upon adoption of the Plan, no further awards are to be made under the EMI Plan.

The fair value of each stock option issued to employees was estimated at the date of grant using Black-Scholes with the following weighted-average assumptions:


	Year Ended,
	2023		2022
Expected volatility	97.1	%	94.7	%
Expected term (years)	6		6
Risk-free interest rate	3.7	%	2.4	%
Expected dividend yield	—	%	—	%

Prior to the IPO, the Company applied a discount for lack of marketability calculated using the Finnerty model

Expected volatility: Previously there was insufficient trading history for the Company’s ordinary shares, therefore the expected price volatility for our ordinary shares was estimated using the average historical volatility of industry peers’ shares as of the grant date of our options over a period of history commensurate with the expected life of the options. When selecting industry peers used in measuring implied volatility, the Company considered the similarity of their products and business lines, as well as their stage of development, size and financial leverage. The Company applied this process consistently using the same or similar public companies until 2023. During 2023, the Company determined that there is sufficient historical information on volatility of its share price available and the expected volatility used in the fair value calculation of new option grants is calculated based on a blended volatility of both historical volatility of the Company's share price and the expected volatility of the average historical volatility of industry peers’ shares.

Expected term (years): Expected term represents the period that the Company’s option grants are expected to be outstanding. There is not sufficient historical share exercise data to calculate the expected term of the stock options. Therefore, the Company elected to utilize the simplified method to value option grants. Under this approach, the weighted-average expected life is presumed to be the average of the vesting term and the contractual term of the option.

Risk-free interest rate: The Company determined the risk-free interest rate by using a weighted-average equivalent to the expected term based on the daily U.S. Treasury yield curve rate in effect as of the date of grant.

Expected dividend yield: The Company does not anticipate paying any dividends in the foreseeable future.

A summary of stock option activity is presented below:


	Number of Stock Options	Weighted- average Exercise Price Per Option		Weighted- average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding, January 1, 2023	4,884,720	$	9.04	7.36	$	2,619
Granted	2,288,236	2.51
Exercised	(72,386)	0.00026
Forfeited/expired	(892,906)	7.30
Outstanding, December 31, 2023	6,207,664	$	6.91	7.95	$	6,044
Exercisable, December 31, 2023	2,839,791	$	8.91	7.33	$	2,883

The weighted-average grant date per-share fair value of stock options granted during the year ended December 31, 2023 was $1.99 per share (December 31, 2022: $3.51 per share). The aggregate intrinsic value of stock options exercised during the year ended December 31, 2023 was $0.2 million (December 31, 2022: $0.8 million). As of December 31, 2023, there was $3.0 million (2022: $7.1 million) of unrecognized compensation cost related to stock options, which is expected to be recognized over a weighted-average period of 1.60 years.

Share based compensation expense is classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Research and development	$	2,011	$	2,668
General and administrative	3,044		7,209
Total	$	5,055	$	9,877

Summary of Significant Accounting Policies - Intangible Assets (Details)	Dec. 31, 2023
Developed technology
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible assets	10 years

Deferred shares (Details) £ / shares in Units, £ in Millions, $ in Millions	Dec. 31, 2023 USD ($)	Dec. 31, 2023 GBP (£) £ / shares	Mar. 29, 2023 £ / shares	Dec. 31, 2022 £ / shares
Deferred A shares
Class of Stock [Line Items]
Ordinary shares, liquidation preference	$ 1.4	£ 1.0
Deferred shares, nominal value (in gbp per share)		£ 1		£ 1
Deferred B shares
Class of Stock [Line Items]
Deferred shares, nominal value (in gbp per share)		0.01	£ 0.01	0.01
Deferred C shares
Class of Stock [Line Items]
Deferred shares, nominal value (in gbp per share)		£ 0.000007	£ 0.00000736245954692556	£ 0.000007

- 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/exampleRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2023
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans In the United Kingdom, the Company has adopted a defined contribution plan (the U.K. Plan) which qualifies under the rules established by HM Revenue & Customs. Contributions to the U.K. Plan are charged to the consolidated statements of operations and comprehensive loss in the year to which they relate. The Company has 401(k) defined contribution retirement plans in which all its employees located in the United States are eligible to participate. Eligible employees may elect to contribute up to the maximum limits, as set by the Internal Revenue Service, of their eligible compensation. Contributions to the plans are charged to the consolidated statements of operations and comprehensive loss in the year to which they relate. During the year ended December 31, 2023, the Company provided a total of $0.7 million (December 31, 2022: $0.5 million) in contributions under both the U.K. Plan and the 401(k) plans.

Nature of Business and Basis of Presentation (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 142,090	$ 194,385
Accumulated deficit	$ 176,590	$ 103,243

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Ordinary Shares (Tables)

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Summary of ordinary shares reserved for future issuance

As of December 31, 2023, the Company has reserved the following ordinary shares for future issuance:


Exercise of stock options			6,207,664
Shares available for future stock incentive plan awards			1,623,840
Total			7,831,504

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of weighted-average assumptions of fair value stock option issued to employees

The fair value of each stock option issued to employees was estimated at the date of grant using Black-Scholes with the following weighted-average assumptions:


	Year Ended,
	2023		2022
Expected volatility	97.1	%	94.7	%
Expected term (years)	6		6
Risk-free interest rate	3.7	%	2.4	%
Expected dividend yield	—	%	—	%

Schedule of stock option activity

A summary of stock option activity is presented below:


	Number of Stock Options	Weighted- average Exercise Price Per Option		Weighted- average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding, January 1, 2023	4,884,720	$	9.04	7.36	$	2,619
Granted	2,288,236	2.51
Exercised	(72,386)	0.00026
Forfeited/expired	(892,906)	7.30
Outstanding, December 31, 2023	6,207,664	$	6.91	7.95	$	6,044
Exercisable, December 31, 2023	2,839,791	$	8.91	7.33	$	2,883

Schedule of share based compensation expense

Share based compensation expense is classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):


	Year ended December 31, 2023		Year ended December 31, 2022
Research and development	$	2,011	$	2,668
General and administrative	3,044		7,209
Total	$	5,055	$	9,877

Prepaid and other current assets

12 Months Ended

Dec. 31, 2023

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Prepaid and other current assets

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


	December 31, 2023		December 31, 2022
Prepayments and accrued income	$	5,402	$	5,887
Value Added Tax receivable	3,031		—

Lease incentives receivable	—		1,770
Other	1,474		611
Total	$	9,907	$	8,268