Clinical Trials: A Sophisticated Process
Drug development is very complex. New drugs must go through several phases of clinical trials before the Food and Drug Administration (FDA) approve them for use within the general public.
Phase I Trials
Are the first studies to evaluate how a new drug or therapy should be administered, including how often and at what dosage. The focus is to determine safety for the next phase of testing. Phase I trials usually treat a small group (20-80 people) in the test group.
Phase II Trials
Are given to a larger group (100-300 people) and provide preliminary information about how well the new drug or therapy works as well as generate more information about its safety and benefits.
Phase III Trials
Are given to an even larger group (1,000-3,000 people) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments and collect information that will allow the experimental drug or treatment to be used safely.
Phase IV Trials
Include the continuing evaluation that takes place after FDA approval, when the therapy is already available for general use.