Clinical trials are phased for very good reasons, AFAIK:
phase 1 is for safety
phase 2 is for efficacy
phase 3 is for dosage
They're not the same. Shortening Phase 1 is automatically a compromise with safety.
phase 1 is for safety
phase 2 is for efficacy
phase 3 is for dosage
They're not the same. Shortening Phase 1 is automatically a compromise with safety.
The reason for sequencing, in the abstract, would be that if Phase 2 looks like "hey, this thing really works!" then the pressure to approve it would become irresistible. Whereas if Phase 1 finds unacceptable side effects, then Phase 2 would never start.
Note again that I'm not saying that's what happened.