As I understand it, the trial was stopped because it failed to meet its endpoint (or wasn't expected to) not because of the adverse effects.

Yes, I realize that.  It's why I said "possible concern" and not "likely a problem".

Both studies include Pembrolizumab and Enzalutamide.  Androgen Deprivation Therapy (ADT) is referred to as a procedure.  I suspect the ADT is less likely a cause of the side effects, though I don't know for sure.  I don't see how adding ZEN-3694 to the other study would be likely to prevent side effects from Pembrolizumab and Enzalutamide.  Also the number of patients with side effects and the magnitude of those side effects is not reported.  More reasons why I said "possible concern" and not "likely a problem".  Sheeeeeeeeeeeeeeeeesh.