Placebo

A placebo is a nonactive control of a clinical trial. The placebo has the components of the drug product minus the [Page 435]active ingredient. FDA guidelines suggest that placebo groups should be used very early in clinical trials to interpret efficacy and safety data. In all phases of clinical investigations, the main objective in using a placebo is to control the study adequately. However, for ethical reasons, in pain studies, pediatric cases, or life-threatening disease states, the use of an active control drug rather than a placebo is desirable.

In placebo-controlled trials the subjects are randomly assigned to a test treatment or an identical appearing treatment that does not include the active test drug. These trials are usually double-blind studies, to control for placebo effect, wherein the subject improves as a result of their impression that they are actually taking the drug. Allowing blinding and randomization in the placebo-controlled studies facilitates control for all potential influences, such as subject's or investigator's expectations, effect of being in the trial, and subjective elements. Placebo control trials help the investigator distinguish the causality of the adverse effects caused by the drug from adverse effects caused by the concomitant disease state.