Clinical trials in developing countries: scientific and ethical issues.

Since the 1994 finding that intensive zidovudine treatment of mothers and infants can dramatically reduce perinatal transmission of human immunodeficiency virus, this treatment has been widely adopted in developed countries. In developing countries, trials of less-intensive (and cheaper) regimens have gone ahead, many funded by foreign governments and the United Nations. Controversy has erupted over these trials, particularly over their use of placebo controls. Do differences in healthcare needs and budgets justify different ethical standards in the developed and the developing world?