Phases Of Clinical Trials
The development process for new cancer treatments occur in four phases. Each phase serves a specific purpose in determining information about the potential new treatment. See the descriptions below for each of the four phases.
Phase I trials involve a small number of patients for whom the new treatment may provide a benefit over existing treatments that have failed. The primary goals of this phase are to determine the drug's activity, appropriate treatment dosing, and any specific side effects related to the drug. Upon successful completion of Phase I, the treatment option will move into Phase II.
Phase II trials are designed to determine effectiveness of the new therapy in treating a specific cancer patient population based on information that was generated in Phase I. Phase II trials involve a higher number of patients and therapies shown to be effective may become standard treatment or be further evaluated in Phase III.
Phase III trials compare the new treatment therapy with the currently existing standard therapy in order to determine proof of effectiveness. Phase III trials require a large number of patients to measure the validity of the treatment results. Oftentimes, a number of cancer centers will participate in Phase III trials to ensure the necessary number of patients are treated in the trial.
After a therapy has been approved for treatment, it will undergo continued evaluation of its effectiveness and monitoring of side effects as well as evaluating the therapy's potential in additional types of cancer.