What's the Difference Between Phase 1, 2, and 3 Trials?

Before any human testing, treatments go through preclinical research in labs. Phase 1 is the first step in humans, focusing on finding the right dose and identifying side effects. If safe, Phase 2 expands to patients with the target condition to measure whether the treatment actually works. Phase 3 involves large-scale trials at multiple sites, often randomized and blinded, providing the evidence needed for FDA approval. Some trials combine phases (Phase 1/2 or Phase 2/3) to accelerate development. Later-phase trials generally offer more data on effectiveness but may have stricter eligibility. Understanding the phase helps you weigh the potential risks and benefits before enrolling.