Another clue could be that they have 4 days to file an 8-K
If the trial was just simply continuing they wouldn't have to tell us. But an endpoint change is a material event, and as I said before, a potential path towards regulatory approval. We know Nader jumps at the chance to explain everything so another CC seems natural in this instance.
Obviously just guessing but maybe it fits. Of course it could be a trial stoppage but it seems like that would have been PR'ed immediately so I don't think it's likely. The other possibility is unblinding but Nader has been unequivocal about that so I'm going with endpoint change as my pick.