v3.26.1
Organization and principal activities - Additional Information (Details) - USD ($)
 3 Months Ended 6 Months Ended
Feb. 04, 2026
Sep. 10, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Date of incorporation       Aug. 29, 2017    
Common stock, shares issued       55,504,574   49,335,551
Net proceeds from shares issued and sold         $ 130,200,000  
Authorized common stock shares       500,000,000   500,000,000
Common stock, par value       $ 0.001   $ 0.001
Accumulated deficit       $ (558,482,000)   $ (489,547,000)
Cash, cash equivalents and marketable securities       494,900,000    
Cash and cash equivalents       $ 202,643,000 $ 264,541,000 $ 189,247,000
Hercules Term Loan Facility            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Term Loan Facility $ 200,000,000          
Initial term loan $ 40,000,000          
Maturity date Feb. 01, 2031          
2026 Sale Agreement            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Sale of common stock maximum aggregate offering price $ 200,000,000          
Common stock, shares issued       0    
Maximum | Hercules Term Loan Facility            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Additional term loan providing up to an aggregate $ 160,000,000          
Maximum | 2026 Sale Agreement            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Commission for agent on sales 3.00%          
Final Tranche | Hercules Term Loan Facility            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Final tranche $ 50,000,000          
Initial Public Offering            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Placement fees, underwriting discounts, commissions and other offering expenses     $ 15,402,000      
Private Placement            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Common stock shares issued and sold   4,000,002        
Price per share   $ 16.25        
Proceeds from private placement   $ 141,300,000        
Placement fees, underwriting discounts, commissions and other offering expenses   $ 8,700,000        
2025 Pre-Funded Warrants            
Organization Consolidation And Presentation Of Financial Statement [Line Items]            
Pre-funded warrants issued   5,231,090        
Purchase price of warrants   $ 16.249        
Exercise price of warrants   $ 0.001