v3.25.4
Segment Information - Schedule of Segment Reporting Financial Information (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Sep. 30, 2025
Revenue      
Total revenue $ 18,615 $ 16,959  
Operating expenses:      
Research and development 20,859 27,656  
General and administrative 9,009 12,846  
Loss from operations (11,253) (23,543)  
Other income (expense):      
Interest expense (3,083) (1,962)  
Interest and investment income, net 2,422 2,799  
Total other (expense) income, net (661) 837  
Loss before income taxes (11,914) (22,706)  
Income tax (expense) benefit (24) 416  
Net loss (11,938) (22,290) $ (81,889)
Royalty [Member]      
Revenue      
Total revenue 18,615 16,959  
Virology [Member]      
Operating expenses:      
Research and development 4,921 18,415  
Virology [Member] | RSV [Member]      
Operating expenses:      
Research and development 4,921 18,415  
Immunology [Member]      
Operating expenses:      
Research and development 14,203 8,621  
Immunology [Member] | KIT [Member]      
Operating expenses:      
Research and development 4,845 4,257  
Immunology [Member] | STAT6 [Member]      
Operating expenses:      
Research and development 7,101 2,287  
Immunology [Member] | MRGPRX2 [Member]      
Operating expenses:      
Research and development 2,257 2,077  
Other programs [Member]      
Operating expenses:      
Research and development 1,735 620  
Other programs [Member] | Early discovery [Member]      
Operating expenses:      
Research and development 1,579 359  
Other programs [Member] | Other Programs for Out-Licensing [Member]      
Operating expenses:      
Research and development $ 156 $ 261