Quarterly report pursuant to Section 13 or 15(d)

Research and Development Agreements - Additional Information (Detail)

v3.22.1
Research and Development Agreements - Additional Information (Detail) - USD ($)
 1 Months Ended 3 Months Ended 107 Months Ended
Aug. 31, 2021
Feb. 28, 2021
Nov. 30, 2019
Sep. 30, 2018
Mar. 31, 2022
Dec. 31, 2021
Mar. 31, 2021
Nov. 30, 2019
Research And Development Collaboration Agreements [Line Items]                
Research and development revenue recognized         $ 8,486,000   $ 3,220,000  
Revenue from grant         8,486,000   3,220,000  
Grant Agreements | Grants Revenue Receivable                
Research And Development Collaboration Agreements [Line Items]                
Reimbursement amounts submitted in excess of amounts received are recorded as receivables         0 $ 0    
Grant                
Research And Development Collaboration Agreements [Line Items]                
Revenue from grant         0   $ 0  
Cancer Prevention and Research Institute of Texas | CPRIT Agreement                
Research And Development Collaboration Agreements [Line Items]                
Product development grant awarded       $ 15,200,000        
Cancer Prevention and Research Institute of Texas | ETB MT-3724 | CPRIT Agreement                
Research And Development Collaboration Agreements [Line Items]                
Aggregate proceeds received from award granted               $ 10,600,000
Revenue from grant         20,000,000.0      
Grants Receivable         0      
Takeda Multi-Target Agreement | Takeda Pharmaceuticals Inc                
Research And Development Collaboration Agreements [Line Items]                
Cumulative payments received         5,000,000.0      
Aggregate milestone payments upon exercise of option to license ETBS         30,000,000.0      
Milestone payments receivable if option is exercised         397,000,000.0      
Deferred revenue         0 2,600,000    
Vertex Collaboration Agreement                
Research And Development Collaboration Agreements [Line Items]                
Milestone payments receivable if option is exercised     $ 180,000,000.0          
Upfront payment     38,000,000.0          
Upfront payment, cash     23,000,000.0          
Upfront payment, equity method investments     15,000,000.0         15,000,000.0
Research and development revenue recognized           14,600,000    
Vertex Collaboration Agreement | Sales Milestone                
Research And Development Collaboration Agreements [Line Items]                
Milestone payments receivable if option is exercised     70,000,000.0          
Vertex Collaboration Agreement | ETBs                
Research And Development Collaboration Agreements [Line Items]                
Aggregate milestone payments upon exercise of option to license ETBS     $ 22,000,000.0         $ 22,000,000.0
Bristol Myers Squibb Collaboration Agreement                
Research And Development Collaboration Agreements [Line Items]                
Milestone payments receivable if option is exercised   $ 874,500,000            
Upfront payment   70,000,000.0            
Transaction price allocated to performance obligations   70,000,000.0            
Deferred revenue, current         34,300,000 32,800,000    
Deferred revenue, non-current         24,300,000 $ 30,700,000    
Bristol Myers Squibb Collaboration Agreement | Sales Milestone                
Research And Development Collaboration Agreements [Line Items]                
Milestone payments receivable if option is exercised   $ 450,000,000.0            
Maximum | Takeda Development and License Agreement                
Research And Development Collaboration Agreements [Line Items]                
Clinical and regulatory milestone payments $ 22,250,000              
Maximum | Takeda Multi-Target Agreement | Takeda Pharmaceuticals Inc                
Research And Development Collaboration Agreements [Line Items]                
Contractual contingency fees         10,000,000.0      
Commercial milestone payment         $ 150,000,000.0