The leading ethical position on placebo-controlled clinical trials is that whenever proven effective treatment exists for a given condition, it is unethical to test a new treatment for that condition against placebo. Invoking the principle of clinical equipoise, opponents of placebo-controlled trials in the face of proven effective treatment argue that they (1) violate the therapeutic obligation of physicians to offer optimal medical care and (2) lack both scientific and clinical merit. We contend that both of these arguments are mistaken. (...) Clinical equipoise provides erroneous ethical guidance in the case of placebo-controlled trials, because it ignores the ethically relevant distinction between clinical trials and treatment in the context of clinical medicine and the methodological limitations of active-controlled trials. Placebo controls are ethically justifiable when they are supported by sound methodological considerations and their use does not expose research participants to excessive risks of harm. (shrink)

The most recent (Fifth) revision of the Declaration of Helsinki, adopted in October 2000 by the World Medical Association (WMA), reinforces the longstanding prohibition against offering placebo instead of effective therapy. The WMA left no doubt that if a beneficial treatment for a condition has already been recognised, it is unethical to offer placebo in place of such treatment to anyone in a study of the same condition. We have previously drawn attention to the discrepancy between the spirit of the (...) Declaration and the common practice of using placebo controls in randomised trials even if effective treatment exists. Despite the mandates of the Declaration of Helsinki and concern from ethicists and scientists, the US Food and Drug Administration (FDA) continues to demand and defend placebo‐controlled evidence of efficacy and safety for the development of many new pharmaceuticals, even if effective therapy exists. We suggest that the FDA's arguments defending their practice are insufficient to justify medical research that violates the Declaration of Helsinki. (shrink)

Placebo-controlled trials are held by many, including regulators at agencies like the United States Food and Drug Administration, to be the gold standard in the assessment of new medical interventions. Yet the use of placebo controls in clinical trials has been the focus of considerable controversy. In this two-part article, we challenge a number of common beliefs concerning the value of placebo controls. Part I critiques statistical and other scientific justifications for the use of placebo controls in clinical research. The (...) continued use of placebo controls in clinical trials on diseases for which accepted treatment exists raises equally important ethical, legal, and regulatory issues for which various justifications have been given. Defense of this practice relies on normative as well as empirical myths.In their attack on the prevailing use of placebo controls, Kenneth Rothman and Karin Michels emphasize that this practice stands in violation of the World Medical Association's guidelines on the ethics of human experimentation, most commonly known as the Helsinki Declaration. (shrink)