Washington Researchers, ethicists and health officials attending a conference at the National Institutes of Health this week defended the use of placebos inert, dummy medicines as an essential tool for evaluating new drugs, and said giving them to patients in a study often can be justified even when there already is a treatment that works.
"There has been a great shift taking place about placebo use," said Sissela Bok, a philosopher and senior fellow at the Harvard Center for Population and Development Studies. "What is clear is that the ethical issues are nowhere near resolved."
Giving placebos to study participants has ignited a fierce ethical debate, after last month's revision of a key international medical document to declare their use unethical whenever the disease being studied already has an effective treatment.
The document, the Declaration of Helsinki, was revised to state that experimental therapies always should be tested against "best current" treatments and that placebos should be used only when no treatment exists.
The changes were made after controversy arose about studies conducted in Africa and Asia of experimental treatments to prevent pregnant women from transmitting the AIDS virus to their infants. An effective treatment already was in routine use in industrialized countries, but was unavailable in the countries where the research took place. Some study participants were given placebos.
Although the three-day NIH conference originally was planned to examine the science of the "placebo effect" the observation that people suffering from various conditions often improve when given a dummy medicine much of the discussion focused on the ethics of placebo use in research.
"Because a couple of very smart, caring people get together somewhere, they don't speak for humanity," said Stephen Straus, director of the National Center for Complementary and Alternative Medicine, which co-sponsored the conference. "Very reasonable people can disagree, and the stakes are very high."
There is widespread consensus in the research community that using placebos is unethical whenever withholding an effective treatment would place study participants at risk of death or lasting disability. Certain kinds of medicines, such as antibiotics, cancer chemotherapy drugs and medicines to treat diabetes, are rarely tested against placebos.
Scientists, health officials and ethicists disagree on what kinds of studies involving placebos may justify subjecting patients to various degrees of risk or suffering, and on whether such choices are best made by study participants, researchers or supervisory bodies.
Various groups charged with overseeing research are studying the newly revised guidelines and trying to decide whether to follow them, Temple said. Some organizations are developing their own alternative standards that provide considerably more leeway.