During which phase of clinical trials is a drug given to a larger group of people to assess its safety and effectiveness?

The phase of clinical trials where a drug is given to a larger group of people to assess its safety and effectiveness is Phase 2. In this phase, researchers evaluate the drug's efficacy and further investigate its safety profile after initial studies in smaller groups (Phase 1) have demonstrated that the drug is generally safe for use.

Phase 2 trials typically involve hundreds of participants, allowing for a more robust assessment of how well the drug works for specific conditions compared to the smaller Phase 1 trials, which focus primarily on safety and dosage rather than effectiveness. The results of Phase 2 studies help determine whether the drug should proceed to larger-scale testing in Phase 3, where even more extensive data on its efficacy and safety is collected in diverse populations.