The World Medical Association has reaffirmed its view that in general it is ethically unacceptable to conduct placebo controlled trials if a proven therapy is available for the condition under investigation.

Following a workshop of the European Agency for the Evaluation of Medicinal Products in London, Dr. Delon Human, Secretary General of the WMA, said that exceptions could be made in certain situations "where for compelling methodological reasons the use of placebo controlled trials are necessary to determine the safety and efficacy of drugs".

Dr Human added: "A good example is where add-on treatment is being tested for the treatment of cancer, while the patients still receive their standard therapy. Another situation is where research is done to find more effective treatments for a minor condition, such as baldness or allergic rhinitis. For this type of clinical situation there would be no additional risk or irreversible harm for the control group, who would be receiving placebo (no treatment)".

The WMA opposes the notion that the non-availability of drugs should be used as a justification to conduct placebo-controlled trials. Dr Human said that "this would lead to poor countries of the world being used as the
laboratory of research institutions of the developed world".

He added: "The WMA and its policies are always focused on what is in the best interest of the individual patients involved in research and in this case persons could easily be exploited".

The WMA is the author of the Declaration of Helsinki, regarded worldwide as the cornerstone of research ethics (a copy is available on www.wma.net).