Quarterly report pursuant to Section 13 or 15(d)

Research and Development Agreements - Additional Information (Detail)

v3.21.2
Research and Development Agreements - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended 107 Months Ended
Aug. 31, 2021
Feb. 28, 2021
Nov. 30, 2019
Sep. 30, 2018
Sep. 30, 2021
Jun. 30, 2021
Sep. 30, 2020
Mar. 31, 2020
Sep. 30, 2021
Sep. 30, 2020
Nov. 30, 2019
Dec. 31, 2020
Research And Development Collaboration Agreements [Line Items]                        
Research and development revenue recognized         $ 2,379   $ 4,298   $ 20,733 $ 12,138    
Common stock, shares issued         56,297,967       56,297,967     49,984,333
Common stock, par value         $ 0.001       $ 0.001     $ 0.001
Revenue from grant         $ 2,379   4,298   $ 20,733 15,348    
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     $ 0
Grant                        
Research And Development Collaboration Agreements [Line Items]                        
Revenue from grant         0   $ 0   0 $ 3,210    
Takeda Pharmaceuticals Inc                        
Research And Development Collaboration Agreements [Line Items]                        
Deferred revenue, current         0       0     789
Deferred revenue, non-current         0       0     3,106
Cancer Prevention and Research Institute of Texas | CPRIT Agreement                        
Research And Development Collaboration Agreements [Line Items]                        
Product development grant awarded       $ 15,200                
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  
Revenue from grant                 20,000      
Grants Receivable         0       0      
Takeda Development Agreement                        
Research And Development Collaboration Agreements [Line Items]                        
Total transaction price                 29,800      
Upfront payment                 30,000      
Development milestone payment that is achievable               $ 10,000        
Expected co-share payments payable         10,200       10,200      
Research and development revenue recognized           $ 12,900            
Deferred revenue         0       0     1,300
Takeda Multi Target Agreement | Takeda Pharmaceuticals Inc                        
Research And Development Collaboration Agreements [Line Items]                        
Deferred revenue         2,600       2,600     2,600
Vertex Collaboration Agreement                        
Research And Development Collaboration Agreements [Line Items]                        
Upfront payment     $ 38,000                  
Upfront payment, cash     23,000                  
Upfront payment, equity method investments     15,000               $ 15,000  
Deferred revenue, current         14,600       14,600     13,900
Deferred revenue, non-current         0       0     $ 4,500
Milestone payments receivable if option is exercised     $ 180,000                  
Common stock, shares issued     1,666,666               1,666,666  
Common stock, par value     $ 0.001               $ 0.001  
Vertex Collaboration Agreement | Common Stock                        
Research And Development Collaboration Agreements [Line Items]                        
Purchase price per share     $ 9.00               $ 9.00  
Fair value of allocated consideration     $ 4,500                  
Vertex Collaboration Agreement | Sales Milestone                        
Research And Development Collaboration Agreements [Line Items]                        
Milestone payments receivable if option is exercised     70,000                  
Vertex Collaboration Agreement | ETBs                        
Research And Development Collaboration Agreements [Line Items]                        
Aggregate milestone payments upon exercise of option to license ETBS     $ 22,000               $ 22,000  
Bristol Myers Squibb Collaboration Agreement                        
Research And Development Collaboration Agreements [Line Items]                        
Upfront payment   $ 70,000                    
Deferred revenue, current         17,500       17,500      
Deferred revenue, non-current         $ 48,700       $ 48,700      
Milestone payments receivable if option is exercised   874,500                    
Transaction price allocated to performance obligations   70,000                    
Bristol Myers Squibb Collaboration Agreement | Sales Milestone                        
Research And Development Collaboration Agreements [Line Items]                        
Milestone payments receivable if option is exercised   $ 450,000                    
Maximum | Takeda Development Agreement                        
Research And Development Collaboration Agreements [Line Items]                        
Clinical and regulatory milestone payments $ 22,250