Written by: Peter W. Stacpoole, PhD, MD
What is a “Clinical Trial”?
Simply put, a clinical trial is an experiment in which the test subjects are human beings, rather than animals or other non-human species. However, clinical trials of new investigational therapies are almost always preceded by many years of research in basic science laboratories on how a drug acts in the body, how safe it is, and how well it works before it can be approved for investigational use in humans.
A clinical trial commonly involves a new therapy or a new use of an established therapy—be it a drug, vaccine, gene, food, or device. (For the purposes of this article the term “drug” is used generally to apply to all types of investigational therapies.) In other words, a clinical trial may involve the testing of a new drug that has never before been administered to humans, or it may be conducted with a drug already approved for certain clinical conditions but not for the use for which it is currently being studied. Many established drugs find new potential uses after they have been approved and administered for months or years in the particular population for which they were originally approved. For example, physicians who prescribe a drug used to treat hypertension might discover during the course of time that it also seems to reduce the frequency and intensity of migraines. This potentially novel use of an established medication requires that the drug undergo formal clinical trials to determine its safety and efficacy in patients for the specific purpose of treating migraine headaches before it can be prescribed for that indication.
No clinical trial can begin without first obtaining the permission of the Food and Drug Administration (FDA). This requires that the maker of an investigational drug, which may be a large pharmaceutical company, a smaller biotech company, or a university faculty member who may have developed the drug in his or her own laboratory, must submit a clinical trial to the FDA that details exactly how the maker intends to conduct a clinical trial in human subjects. The FDA then issues an Investigational New Drug (IND) permit to allow the sponsor to proceed with the trial.
Who Conducts Clinical Trials and Where?
Clinical research is complex and requires teamwork among a number of health professionals and scientists. Thus the investigators who conduct a clinical trial may include physicians, nurses, and dieticians who work directly with the subjects, laboratory-based scientists who analyze specimens obtained from the subjects, and biostatisticians who help with the design and analysis of the clinical and laboratory data that is generated by the study.
Clinical trials can occur in many locations. In an academic setting, however, they are typically conducted in outpatient clinics or in specially designed areas in which patient-oriented research is conducted. Traditionally, and particularly for the study of treatments for rare disorders, these specialized units have been General Clinical Research Centers (GCRCs). For over 40 years the National Institutes of Health (NIH), which funds the vast majority of clinical research conducted at U.S. academic health centers, has supported GCRCs as locations for conducting research into the diagnosis, causes, treatment, and prevention of human disease.
Current changes in the support of clinical research by the NIH is leading to the gradual transformation of GCRCs into what are often called Clinical and Translational Research Centers or Institutes. A major goal of these new organizations is to accelerate the transformation of medical research (such as new drug development) into approved therapies for use in patients (See Box 1 below).
Peter W. Stacpoole, PhD, MD is Professor of Medicine, Biochemistry and Molecular Biology; Director, General Clinical Research Center; Director, Clinical and Translational Science Institute; and Associate Dean, Clinical Research and Training at the University of Florida College of Medicine in Gainesville, FL.