In “Ethical considerations of experimental interventions in the Ebola outbreak“, published yesterday by The Lancet, Zeke Emanuel and I discuss what we take to be the key ethical questions about the use of Zmapp and other investigational agents in the current Ebola epidemic. In essence, we argue that the national and international response to the epidemic should focus on containment and strengthening health systems, rather than experimental treatments and vaccines; that experimental interventions, if they are used, should be distributed fairly and only in the context of clinical trials; and that advance planning is needed for research in future Ebola and other epidemics, as well as for making any proven interventions against Ebola accessible in affected regions.
Placebo controls usually get special treatment. Almost all ethical guidelines for research specify how to use placebo controls, in particular when an established or proven effective treatment exists. To list just a few: guidance issued by the World Medical Association, CIOMS and the Council of Europe all have provisions dedicated to the use of placebo controls. But is there any reason to consider placebo controls a special case? I believe there isn’t, and I also think the burden of proof is on those who hold that placebos should be evaluated differently from other research interventions.
Using a placebo when an established effective treatment exists deprives the control group of the benefits of that treatment. This poses relative net risks to participants – that is, risks from delaying or foregoing a treatment that participants may have received outside the trial. Some placebo interventions also pose risks themselves, but these risks are typically so low – taking a “sugar pill” or receiving a saline injection through an existing i.v. line, for example – that we rightly focus on the risks of foregoing or delaying treatment. (There are other cases, though, such as certain forms of sham surgery. I won’t consider these cases here.)
So how should we evaluate the risks of using a placebo when an established effective treatment exists? We have general criteria for evaluating the risks of research interventions, in particular:
Annette Rid is a Senior Lecturer in Bioethics and Society at the Department of Social Science, Health & Medicine, King’s College London, where she co-directs a new MA in Bioethics & Society. She also is an Affiliated Research Fellow at the Institute of Biomedical Ethics, University of Zurich, and a member of the working group to revise the 2002 CIOMS International Ethical Guidelines for Biomedical Research Involving Human Subjects. In the past, Annette has worked at the Department of Bioethics, National Institutes of Health; the Ethics & Health Unit, World Health Organization; the Secretariat of the Parliamentary Commission on “Ethics and Law in Medicine”, German Parliament; and the neonatal intensive care unit, Charité University Medicine Berlin.