Phases of Clinical Trials
There are four phases in the development of new cancer treatments. Each phase is designed to determine specific information such as risks, safety and effectiveness of investigated therapy as compared to standard therapy. The goal is to create therapy options with improved safety, outcome or both.
Phase I Trials:
Phase I is the most important step in the development of a new drug or therapy. Phase I trials involve a small number of patients for whom standard therapies have failed or for whom alternative therapy is unavailable. While Phase I therapy may produce anti-cancer effects and provide patient benefits, the primary goals are to determine the anticancer activity, the maximum tolerated dose, and the side effect profile of the investigated therapy.
Phase II Trials:
Phase II trials determine the effectiveness of the treatment in a specific patient population at the dose and schedule determined in Phase I. A greater number of patients may receive treatment with the number continuing to increase depending on the response to treatment. Therapies that are shown to be effective in Phase II trials may become standard of care or be further evaluated in Phase III trials.
Phase III Trials:
Phase III trials compare a new drug to the current standard of care treatment. The definitive assessment between safety and effectiveness of therapies requires a large number of patients and a long amount of time. It is sometimes called the “pre-marketing phase” because it is the final evaluation prior to the drug being made commercially available.
Phase IV Trials:
Phase four is known as post marketing surveillance. This involves the monitoring of safety and ongoing technical support during the utilization of a specific new drug.