The biotechs work with the FDA to design trials but they choose their endpoints or at least that is my understanding. I have previously posted a video from RAC where the CEO was discussing trial design and how a lot of good drugs and therapies are lost because they fail trials due to poor trial design. Well worth a listen.
To be fair, things evolved quickly with treatments with covid and the patients and outcomes they were getting early were not the same as those in Phase 3 because of the different treatments the patients received prior to the trial. In a more normal situation, the patients would have been more homogenous as treatments don't normally evolve that quickly.
