Dictionary of Cancer Terms
View in Spanish: Ensayo de fase III
Phase III trial
A study to 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 only after a treatment seems to work in phases I and II. Phase III trials may include hundreds of people.
Source: National Cancer Institute Dictionary of Cancer Terms, available at www.cancer.gov/dictionary.