The Ethics of Placebo-Controlled Trials

Placebo-controlled clinical trials are often considered the gold standard for evaluation of a new therapy because they are thought to provide the most definitive test of efficacy. The U.S. Food and Drug Administration (FDA), which is charged with ensuring both safety and efficacy, frequently requires pharmaceutical companies to perform placebo-controlled trials before a new drug is approved.

Critics of such trials, however, believe that it is unethical to give patients a placebo when an approved therapy exists, even when the required informed consent has been provided. For support, they point to the Declaration of Helsinki, a document first ratified by the World Medical Association (WMA) in 1964 that contains guidelines for the ethics of research involving human subjects. Article II.3, which states that “In any medical study, every patient—including those of a control group, if any—should be assured of proven effective prophylactic, diagnostic, and therapeutic methods,” is the key point on which the debate hinges.

“There is an increasing polarity about this issue in the research community,” said Bette Crigger, PhD, a linguistic anthropologist at the Hastings Center in Hastings-on-Hudson, New York, and editor of the journal IRB. “There are arguments as to whether the randomized, placebo-controlled trial should really be considered the scientific gold standard it is said to be,” she stated.

Robert Levine, MD, chairman of the Human Investigation Committee at Yale School of Medicine in New Haven, Connecticut, formerly chaired a WMA study group that is evaluating the declaration and preparing to propose a revision. According to Levine, article II.3 “is vastly out of line with common practice. It's quite routine that we use placebos …