Phase 2 : Is it showing any signs of efficacy?
If an experimental treatment is found to be safe in Phase 1 clinical trials, then Phase 2 clinical trials are initiated. Phase 2 trials assess the potential efficacy of the experimental treatment. Usually, participants receive the dose set in the Phase 1 clinical trials. At this stage, doctors are looking for a signal of efficacy. For example, does the experimental treatment help control tumour growth?
Phase 2 clinical trials are usually conducted with a few dozen to a few hundred people.