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Definition of Phase 1 Clinical Trials


Updated September 19, 2012


Phase 1 clinical trials are done to see if an experimental medication or treatment is safe. After a treatment is tested in the lab or on animals, it enters a phase 1 clinical trial that is done with humans. These trials usually involve only a small number of people to determine if a drug or treatment is safe, and to determine the best dose of a drug and how it should be given (whether orally or intravenously).

If a treatment appears safe at the end of a phase 1 clinical trial, it may then enter a phase 2 trial, a study done to see if a treatment is effective. If a drug or treatment is deemed safe in a phase 1 trial and effective in a phase 2 trial, it will then enter a phase 3 clinical trial. Phase 3 clinical trials are much larger, and are done to see if a treatment is not only safe and effective, but works better or has fewer side effects than treatments currently available.

Also Known As: phase I clinical trials
Ben decided to participate in a phase 1 clinical trial for his lung cancer. The study is designed to see if a new drug is safe. Chances are it will not benefit him significantly, but lung cancer runs in his family and hopes to have a chance to further research for his children and grandchildren.
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