Clinical Trials
Clinical research is usually conducted in a series of trials that become progressively larger. A phase I clinical trial is directly built upon the lessons learned from basic and animal research and is used to test the safety of therapy for a particular disease and to estimate possible efficacy in a few human subjects. A phase II clinical trial usually involves many subjects at several different centers and is used to test safety and possible efficacy on a broader scale, to test different dosing for medications or to perfect techniques for surgery, and to determine the best methodology and outcome measures for the bigger phase III clinical trial to come.
A phase III clinical trial is the largest endeavor in clinical research. This type of trial often involves many centers and many subjects. The trial usually has two patient groups who receive different treatments, but all other standard care is the same and represents the best care available. The trial may compare two treatments, or, if there is only one treatment to test, patients who do not receive the test therapy receive instead a placebo. The patients are told that the additional treatment they are receiving may be either the active treatment or a placebo. Many phase III trials are called double-blind, randomized clinical trials. Double-blind means that neither the subjects nor the doctors and nurses who are treating the subjects and determining the response to the therapy know which treatment a subject receives. Randomization refers to the placing of subjects into one of the treatment groups in a way that can't be predicted by the patients or investigators. These clinical trials usually involve many investigators and take many years to complete. The hypothesis and methods of the trial are very precise and well thought out. Clinical trial designs, as well as the concepts of blinding and randomization, have developed over years of experimentation, trial, and error. At the present time, researchers are developing new designs to maximize the opportunity for all subjects to receive therapy.
Most treatments for general use come out of phase III clinical trials. After one or more phase III trials are finished, and if the results are positive for the treatment, the investigators can petition the FDA for government approval to use the drug or procedure to treat patients. Once the treatment is approved by the FDA, it can be used by qualified doctors throughout the country. The back packet of this brochure contains cards with information on some of the many stroke clinical trials the NINDS supports or has completed
- View ongoing clinical trials at JFK Medical Center.
