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Stockholders' equity (Details)
1 Months Ended 3 Months Ended
Mar. 11, 2024
USD ($)
$ / shares
shares
Nov. 12, 2020
USD ($)
Feb. 28, 2023
USD ($)
$ / shares
shares
Mar. 31, 2024
USD ($)
Vote
$ / shares
shares
Mar. 31, 2023
USD ($)
shares
Jan. 26, 2024
USD ($)
Dec. 31, 2023
$ / shares
shares
Common stock              
Stock, shares authorized | shares       440,000,000      
Common stock, shares authorized | shares       400,000,000     400,000,000
Common stock, par value (in dollars per share) | $ / shares       $ 0.001     $ 0.001
Preferred stock, shares authorized | shares       40,000,000      
Preferred stock, par value (in dollars per share) | $ / shares       $ 0.001      
Common stock issuable upon conversion (in shares) | shares       28,112      
Number of voting rights per common share | Vote       1      
Stock based compensation expense       $ 85,830 $ 16,244    
Shelf Registration Statement              
Proceeds from issuance of common stock       15,999,598 5,788,918    
Common stock issuance costs       1,289,893 $ 648,928    
March 2024 Private Placement              
Warrant exercises       $ 0      
Series A Convertible Preferred Stock              
Common stock              
Convertible preferred stock, shares outstanding | shares       56,227     56,227
March 2024 Private Placement | Purchasers | Securities purchase agreement              
Shelf Registration Statement              
Shares issued | shares 1,687,712            
Common stock issuance costs $ 1,300,000            
March 2024 Private Placement              
Offering price per share | $ / shares $ 7.29            
Warrants to purchase of shares | shares 507,076            
Common stock with an exercise price | $ / shares $ 0.001            
Percentage of outstanding shares 4.99%            
Proceeds from sale of common stock in a private placement $ 16,000,000.0            
Expected gross proceeds from potential future warrants cash exercise $ 18,000,000.0            
March 2024 Private Placement | Purchasers | Securities purchase agreement | At the election of holder              
March 2024 Private Placement              
Percentage of outstanding shares 9.99%            
March 2024 Private Placement | Purchasers | Securities purchase agreement | Pre-funded Warrants              
March 2024 Private Placement              
Offering price per share | $ / shares $ 7.29            
March 2024 Private Placement | Purchasers | Securities purchase agreement | Tranche A Warrants (Pre-funded Warrants Exercise Price 7.29 Per Share)              
March 2024 Private Placement              
Warrants to purchase of shares | shares 1,097,394            
Common stock with an exercise price | $ / shares $ 7.29            
Stock issuance anniversary period 3 years            
Number of days after announcement of Phase 2 dose for ATRN-119 30 days            
Volume weighted average price | $ / shares $ 14.58            
Number of consecutive trading days 30 days            
March 2024 Private Placement | Purchasers | Securities purchase agreement | Tranche B Warrants (Pre-funded Warrants Exercise Price 9.1125 Per Share)              
March 2024 Private Placement              
Common stock with an exercise price | $ / shares $ 9.1125            
Stock issuance anniversary period 5 years            
Number of days after announcement of Phase 2 dose for ATRN-119 30 days            
Volume weighted average price | $ / shares $ 18.225            
2020 Shelf Registration Statement              
Shelf Registration Statement              
Maximum amount to be issued under universal shelf registration statement   $ 350,000,000.0          
2020 Shelf Registration Statement | Common Stock              
Shelf Registration Statement              
Shares issued | shares     1,050,000        
Issue price per share | $ / shares     $ 5.25        
Proceeds from issuance of common stock     $ 4,900,000        
Common stock issuance costs     $ 600,000        
ATM offering              
Common stock              
Commission payable as a percentage of gross proceeds from sale of common stock under ATM offering   3.00%          
Shelf Registration Statement              
Maximum amount to be issued under at-the-market offering program   $ 14,744,728          
Shares issued | shares         26,302    
Proceeds from issuance of common shares         $ 300,000    
Common stock issuance costs         $ 8,000    
2024 Shelf Registration Statement              
Shelf Registration Statement              
Maximum amount to be issued under universal shelf registration statement           $ 150,000,000  
Maximum amount to be issued under at-the-market offering program           1,000,000  
Maximum amount to be issued under at-the-market offering program, supplement           2,000,000  
2024 ATM offering | HCW              
Shelf Registration Statement              
Maximum amount to be issued under at-the-market offering program           $ 2,000,000