Phase 3 clinical trials primarily determine what?

Phase 3 clinical trials are primarily designed to compare a new treatment to the current standard of care to evaluate its effectiveness. This phase typically involves a large number of participants and aims to provide definitive evidence on whether the new treatment works better than the existing treatments available. The results from these trials help determine if the new drug should be made available to the public and can influence treatment guidelines for specific conditions.

While assessing safety does begin in earlier phases, and commercial viability can be influenced by the results of a phase 3 trial, the main goal is to establish the superiority (or non-inferiority) of the new treatment regarding efficacy. Quality of life assessments can also be part of phase 3 trials, but they are generally considered secondary outcomes and not the primary objective, which is focused on efficacy in comparison to current standards.