Certified Clinical Research Associate (CCRA) Practice Exam 2025 – Complete Preparation Guide

Phase 2 clinical studies are primarily designed to evaluate the efficacy of a drug or treatment and further assess its safety. These studies typically involve a larger group of participants compared to Phase 1 trials, which focus primarily on safety and dosage.

In Phase 2 studies, the participant count is generally in the range of a few hundred, often between 100 to 300. This size allows for a more robust assessment of the treatment's effectiveness while still being manageable in terms of resources and patient monitoring. It is crucial to gather sufficient data, as the findings from Phase 2 are instrumental in determining whether the treatment should progress to Phase 3, which involves larger populations and further evaluation of the drug’s effectiveness and safety.

While some studies could involve lower or higher participant numbers based on the specifics of the trial, the general expectation is that several hundred participants will be included to provide meaningful data on the intervention’s performance. This approach balances statistical power with feasibility in clinical settings.