A Phase 2 clinical trial is a type of clinical trial that tests the safety and efficacy of an experimental drug on a particular disease or condition in a group of up to several hundred patients with the disease or condition. The goal of a Phase 2 clinical trial is to determine whether the experimental drug works for a specific disease or condition and to collect additional safety data. In Phase 2 studies, researchers administer the drug to a group of patients with the disease or condition for which the drug is being developed. Typically, these studies involve a few hundred patients and last several months to two years. The results of Phase 2 clinical trials are used to refine research questions, develop research methods, and design new clinical trials.