v3.25.4
Revenue and entity-wide disclosures - Narrative (Details)
SFr in Thousands, $ in Millions
12 Months Ended 40 Months Ended
Dec. 31, 2025
CHF (SFr)
Dec. 31, 2024
CHF (SFr)
Dec. 31, 2023
CHF (SFr)
Dec. 31, 2022
CHF (SFr)
Mar. 31, 2025
CHF (SFr)
Mar. 31, 2025
USD ($)
Disclosure of disaggregation of revenue from contracts with customers [line items]            
Research and development expense SFr 40,194 SFr 48,604 SFr 48,784      
Total Revenues 0 4,970 7,038      
Co-development Agreement with Orano Med            
Disclosure of disaggregation of revenue from contracts with customers [line items]            
Research and development expense reimbursement SFr 2,300          
Research and development expense   600        
Licence and Collaboration Agreement with Novartis            
Disclosure of disaggregation of revenue from contracts with customers [line items]            
Total Revenues   SFr 5,000 SFr 7,000   SFr 18,600 $ 20.0
Novartis Option and Equity Rights Agreement            
Disclosure of disaggregation of revenue from contracts with customers [line items]            
Total Revenues       SFr 150,000