Phase 2 Clinical Trials

Phase 2 Later clinical stage Phase 2 studies are designed to evaluate the short-term therapeutic effect of a new drug in Pts who suffer from the target disease, and confirm the safety established in phase I trials.

Phase 2 studies are sometimes placebo-controlled, often double-blinded, enrol a larger number of Pts than in phase 1 and Pt follow-up may be for longer periods; phase 2 studies are tailored to specific treatment indications for which the company plans to seek broader approval; where compelling scientific evidence is presented, the Regulatory Authority expedites review of a company's application for market clearance; expedited review of phase 2 clinical data, and clearance of that early application, can obviate requirements for phase 3 trials; phase 2's involve several hundred Pts and generate enough data to 1. at least suggest–if not prove that the drug actually works–efficacy and 2. demonstrate the most common side effect.sPhase 2 trials are sometimes divided into phase 2a pilot trials and phase 2b well-controlled trials

Source: McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.