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Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jan. 01, 2024	Apr. 08, 2021	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2018
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares available for future grants (in shares)			7,285,275	6,207,664
Number of shares reserved for issuance (in shares)			9,191,355
Weighted-average grant date fair value (in usd per share)			$ 2.66	$ 1.99
Aggregate intrinsic value of stock options exercised			$ 0.4	$ 0.2
Unrecognized compensation cost related to options			$ 3.1	$ 3.0
Stock options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average period over which unrecognized compensation cost is expected to be recognized			1 year 5 months 15 days	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)	1,544,282
Expiration period		10 years
Vesting period		3 years
Shares available for future grants (in shares)			1,906,080	1,623,840
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