v3.26.1
Stockholders' equity (Details)
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
Mar. 30, 2026
USD ($)
$ / shares
shares
Jan. 28, 2026
USD ($)
$ / shares
shares
Dec. 08, 2025
USD ($)
$ / shares
shares
Apr. 30, 2025
shares
Jun. 30, 2026
USD ($)
$ / shares
shares
Jun. 30, 2025
USD ($)
shares
Jun. 30, 2026
USD ($)
Vote
$ / shares
shares
Jun. 30, 2025
USD ($)
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Mar. 31, 2026
USD ($)
shares
Mar. 31, 2025
shares
Dec. 31, 2024
shares
Nov. 08, 2024
USD ($)
Common stock                          
Stock, shares authorized         440,000,000   440,000,000            
Common stock, shares authorized         400,000,000   400,000,000   400,000,000        
Common stock, par value (in dollars per share) | $ / shares         $ 0.001   $ 0.001   $ 0.001        
Preferred stock, shares authorized         40,000,000   40,000,000            
Preferred stock, par value (in dollars per share) | $ / shares         $ 0.001   $ 0.001            
Number of voting rights per common share | Vote             1            
Stock based compensation expense | $         $ 100,000 $ 100,000 $ 200,000 $ 300,000          
Shelf Registration Statement                          
Proceeds from issuance of common stock | $             35,598,881 459,019          
Common stock issuance costs | $             2,912,439 18,291          
Private Placement                          
Common stock issuance costs | $             2,912,439 $ 18,291          
Warrant exercises | $             $ 0   $ 0        
December 2025 Warrants                          
Private Placement                          
Common stock with an exercise price | $ / shares         $ 1.04   $ 1.04            
January 2026 Warrants                          
Private Placement                          
Common stock with an exercise price | $ / shares         0.765   0.765            
March 2026 Warrants                          
Private Placement                          
Common stock with an exercise price | $ / shares         $ 0.683   $ 0.683            
Common Stock                          
Common stock                          
Conversion of preferred stock into common stock (in shares)       12,516                  
Series A Convertible Preferred Stock                          
Common stock                          
Convertible preferred stock, shares outstanding         31,194 31,194 31,194 31,194 31,194 31,194 56,227 56,227  
Number of shares remained to be converted into common stock         15,596   15,596   15,596        
Conversion of preferred stock into common stock (in shares)       25,033   25,033              
Private Placement | Pre-funded Warrants                          
Private Placement                          
Warrants to purchase of shares         41,099,626   41,099,626            
March 2024 Private Placement | Pre-funded Warrants                          
Private Placement                          
Warrant exercises | $                 $ 91        
Class of warrant or right, number of warrants exercised                 91,206        
December 2025 Private Placement | Pre-funded Warrants                          
Private Placement                          
Warrant exercises | $             $ 0   $ 0        
Class of warrant or right, number of warrants exercised             1,376,405   1,198,700        
December 2025 Private Placement | Purchasers | Securities purchase agreement                          
Shelf Registration Statement                          
Shares issued     26,459                    
Common stock issuance costs | $     $ 400,000                    
Private Placement                          
Issuance of common stock (in shares)     26,459                    
Offering price per share | $ / shares     $ 1.165                    
Stock issuance anniversary period     5 years                    
Proceeds from sale of common stock in a private placement | $     $ 3,100,000                    
Common stock issuance costs | $     $ 400,000                    
December 2025 Private Placement | Purchasers | Securities purchase agreement | Pre-funded Warrants                          
Private Placement                          
Offering price per share | $ / shares     $ 1.164                    
Warrants to purchase of shares     2,596,564                    
Common stock with an exercise price | $ / shares     $ 0.001                    
December 2025 Private Placement | Purchasers | Securities purchase agreement | December 2025 Warrants                          
Private Placement                          
Warrants to purchase of shares     2,880,533                    
Common stock with an exercise price | $ / shares     $ 1.04                    
December 2025 Private Placement | Placement Agent | Securities purchase agreement | December 2025 Warrants                          
Private Placement                          
Warrants to purchase of shares     257,510                    
January 2026 Private Placement | Pre-funded Warrants                          
Private Placement                          
Warrant exercises | $         $ 0   $ 0            
Class of warrant or right, number of warrants exercised         400,000   923,596            
January 2026 Private Placement | Purchasers | Securities purchase agreement                          
Shelf Registration Statement                          
Shares issued   1,877,677                      
Common stock issuance costs | $   $ 500,000                      
Private Placement                          
Issuance of common stock (in shares)   1,877,677                      
Offering price per share | $ / shares   $ 0.8891                      
Common stock issuance costs | $   $ 500,000                      
Issuance of gross proceeds | $   $ 5,600,000                      
January 2026 Private Placement | Purchasers | Securities purchase agreement | Pre-funded Warrants                          
Private Placement                          
Offering price per share | $ / shares   $ 0.8881                      
Warrants to purchase of shares   4,411,180                      
Common stock with an exercise price | $ / shares   $ 0.001                      
January 2026 Private Placement | Purchasers | Securities purchase agreement | January 2026 Warrants                          
Private Placement                          
Warrants to purchase of shares   6,288,857                      
Common stock with an exercise price | $ / shares   $ 0.765                      
Stock issuance anniversary period   2 years                      
March 2026 Private Placement                          
Private Placement                          
Subscription receivable | $                   $ 500,000      
March 2026 Private Placement | Purchasers | Securities purchase agreement                          
Shelf Registration Statement                          
Common stock issuance costs | $ $ 2,300,000                        
Private Placement                          
Common stock issuance costs | $ 2,300,000                        
Issuance of gross proceeds | $ $ 30,000,000                        
March 2026 Private Placement | Purchasers | Securities purchase agreement | Pre-funded Warrants                          
Private Placement                          
Offering price per share | $ / shares $ 0.807                        
Warrants to purchase of shares 37,174,713                        
Common stock with an exercise price | $ / shares $ 0.001                        
March 2026 Private Placement | Purchasers | Securities purchase agreement | March 2026 Warrants                          
Private Placement                          
Warrants to purchase of shares 37,174,713                        
Common stock with an exercise price | $ / shares $ 0.683                        
2024 Shelf Registration Statement                          
Shelf Registration Statement                          
Maximum amount to be issued under at-the-market offering program, supplement | $                         $ 3,000,000
2024 Shelf Registration Statement | HCW                          
Shelf Registration Statement                          
Maximum amount to be issued under at-the-market offering program | $                         $ 3,000,000
2024 ATM offering                          
Shelf Registration Statement                          
Shares issued                 1,337,948        
Proceeds from issuance of common stock | $                 $ 1,900,000        
Common stock issuance costs | $                 $ 76,000        
Private Placement                          
Issuance of common stock (in shares)                 1,337,948        
Common stock issuance costs | $                 $ 76,000