Expert Support
The Placebo Paradox
Dr. Mark Freedman, Neurologist
When is it okay to treat one person and not another? Why placebos still have a place in (some) MS clinical trials
The choice of whether to use placebos in clinical trials has become a modern ethical question in MS research. The placebo provides a scientifically strong basis for comparison when testing a drug. But because there are known, effective medications available for MS treatment, and because experts now understand the importance of treating MS as early as possible, doctors question whether it is ethical to use a placebo at all in today's clinical trials.
To revisit the problem, an international group of researchers, including Dr. Mark Freedman, director of the MS Research Unit at the Ottawa Hospital, published a report in March in the journal Neurology as part of a special issue devoted to MS topics. The report considers the wide variety of factors involved, including possibilities for trial designs, financial factors for trial participants, available treatments for different types of patients including children, cases of patients who do not respond to drugs, and the patients' informed consent to their role in the trial.
“Even though we have ‘effective’ treatments, we also recognize their limitations, and that they are not ‘cures’,” says Dr. Freedman. “The placebo-controlled study is still the most powerful way to prove efficacy of a new drug and in its absence it would be considerably harder to provide credible evidence of a drug’s positive effect.”
The authors found that placebos could be used ethically under certain conditions. The report provides recommendations about when a placebo is justified, including limited situations in which there is no increased risk of harm to patients (such as in forms of MS for which there are no known effective treatments, or in cases of patients who refuse the treatment or who already know they do not respond to the treatment).
The authors provide alternative clinical trial designs that do not use placebos and discuss the complications of using these designs. “The reason we also tackled the ethics of study design,” Dr. Freedman explains, “is because it would be unethical to subject a patient to a study whose design is unproven or flawed and therefore unable to yield the desired results.”
“Placebo-controlled clinical trials may still be done ethically in MS,” the authors conclude, noting that alternative trials “have been little explored in MS, and each presents its own ethical challenges.” The report further recommends that people who participate in clinical trials should not be influenced, and should fully understand their decision to participate.
This feature is intended solely for informational purposes and is not a substitute for routine or urgent medical evaluation, treatment or consultation. Dr. Freedman’s guest editorial should not be construed as a medical opinion aimed at establishing a diagnosis or course of treatment. Individuals who are being treated should not construe information here as replacing or superseding recommendations of their own physician.
