Based upon a recent discussion we had with a urologic oncologist, the IMvigor010 adjuvant study may have failed specifically because of the patient population (initially only enrolled muscle invasive urothelial carcinoma, nodal status in overall study was ~53%): Full results of IMvigor010 were presented during ASCO 2020 and failed to show any benefit. The ASCO 2020 analysis was performed after 50% of DFS events had occurred within each of the arms, atezolizumab and control, and roughly ~30% of survival events.
The AMBASSADOR study of pembrolizumab has a slightly different design versus CheckMate-274 for adjuvant treatment of invasive bladder cancer following surgery, but does include a similar patient population: The AMBASSADOR study is sponsored by the National Cancer Institute (NCI), and based upon relative timing disclosed on clinictrials.gov could have first results during 2021 (our guess). That said, we are not sure that using a co-primary endpoint of DFS + Overall Survival (OS) within AMBASSADOR would support the same interim analysis as CheckMate-274, which used DFS as the singular primary endpoint and includes OS as a secondary endpoint (Disease Free Survival defined as the time between the date of randomization and the date of first recurrence or death (of any cause) whichever occurs first.).