v3.25.4
Income taxes - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Income Taxes [Line Items]    
U.K. tax rate 25.00% 25.00%
Tax expense related to current tax $ 11,000 $ 845,000
Deferred tax expense 0  
Deferred tax liabilities 0 0
SME scheme    
Income Taxes [Line Items]    
Tax credit 7,500,000 13,200,000
RDEC scheme    
Income Taxes [Line Items]    
Tax credit   300,000
Collaboration Agreement with Hansoh    
Income Taxes [Line Items]    
Milestone payments received $ 0 2,000,000
Milestone payment, tax withholding   $ 200,000