phase III trial
Phase III trials compare the results of people taking a new treatment with the results of people taking the standard treatment (for example, which group has better survival rates or fewer side effects). In most cases, studies move into phase III trials only after a treatment seems to work in phases I and II. Phase III trials may include hundreds of people.
For more information, see Breastcancer.org's Clinical Trials section or read about studies in Research News.
Audio contributed by: Marisa Weiss, M.D.
