v3.25.4
Common stock and common stock warrants - Warrants (Details) - Common Stock Warrant - $ / shares
Dec. 31, 2025
Dec. 31, 2024
Common stock and common stock warrants    
Shares of common stock issuable upon exercise of warrant (in shares) 1,199,248 1,020,144
July 24, 2017    
Common stock and common stock warrants    
Contractual term 10 years 10 years
Shares of common stock issuable upon exercise of warrant (in shares) 15,035 15,035
Weighted average exercise price (in dollars per share) $ 298.96 $ 298.96
April 12, 2018    
Common stock and common stock warrants    
Contractual term 10 years 10 years
Shares of common stock issuable upon exercise of warrant (in shares) 30,000 30,000
Weighted average exercise price (in dollars per share) $ 1.00 $ 1.00
July 14, 2021    
Common stock and common stock warrants    
Contractual term 10 years 10 years
Shares of common stock issuable upon exercise of warrant (in shares) 975,109 975,109
Weighted average exercise price (in dollars per share) $ 1.46 $ 1.46
August 8, 2025    
Common stock and common stock warrants    
Contractual term 10 years  
Shares of common stock issuable upon exercise of warrant (in shares) 179,104  
Weighted average exercise price (in dollars per share) $ 3.35