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Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jan. 01, 2025	Apr. 08, 2021	Oct. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2018
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares available for future grants (in shares)				5,976,157	7,285,275
Number of shares reserved for issuance (in shares)				9,224,762
Weighted-average grant date fair value (in usd per share)				$ 0.85	$ 2.66
Aggregate intrinsic value of stock options exercised				$ 200	$ 400
Unrecognized compensation cost related to options				600	3,100
Share based compensation expense				$ 468	4,709
RSU's
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period			7 days
Weighted-average period over which unrecognized compensation cost is expected to be recognized				8 months 12 days
Awards granted (in shares)			886,018	886,018
Grant fair value of awards			$ 1,300
Share based compensation expense				$ 500	$ 0
Unrecognized compensation expense				$ 800
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 1 day	1 year 5 months 15 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)	1,609,386
Expiration period		10 years
Vesting period		3 years
Shares available for future grants (in shares)				3,248,605	1,906,080
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