Sir

Your editorial, “Setting a bad example on AIDS”, correctly points out the immediate consequences of the decision by South Africa's health minister, Nkosazana Zuma, not to fund the supply of the drug AZT for HIV-infected pregnant women (Nature 396, 603; 1998). But the impact goes far beyond the ultimate death of possibly thousands of infants who will be denied the potential benefit of AZT.

There are far-reaching implications which threaten the often difficult and complex proceedings that determine the design of clinical studies in developing countries; the commitment of pharmaceutical companies which evaluate therapies for developing countries; and the willingness of such companies to negotiate reduced prices for developing countries.

Current perinatal HIV prevention studies, aimed at reducing cost while preserving efficacy, have been designed with developing countries in mind. The availability of a drug following completion of a study in the host country is part of the ethical deliberations that are seriously considered before the approval of a clinical study. While an absolute guarantee is not required, the ethical review committee requires a certain degree of assurance that the host country and the pharmaceutical company will act in good faith to try to make a drug available.

Zuma's decision has escaped no one's attention. South Africa receives many grants from foreign agencies for clinical drug studies and hosts many drug studies sponsored by pharmaceutical companies. Pharmaceutical companies entered into negotiations with several developing countries to supply AZT at reduced cost to prevent perinatal HIV transmission. Zuma's decision may affect the willingness of scientists, funding agencies and companies to embrace trials in South Africa or other developing countries.

In addition, health ministers of poorer countries might use South Africa as an example to justify suspension of other public health measures, and pharmaceutical companies may begin to view drug evaluation in developing countries as too risky. The decision threatens to undermine the efforts of many of us who are trying to convince companies that they must provide approved drugs for evaluation in developing countries and support investigations of new drugs. Alienation of the academic community and pharmaceutical companies threatens to ‘bite the hand’ that has the potential to control the HIV epidemic.

It is not for scientists or funding agencies in developed countries to dictate what must be done in developing countries, nor for pharmaceutical companies to determine what drugs are necessarily best for a country with limited resources. However, if scientists, funding agencies and pharmaceutical companies respond to the desperate needs of developing countries and receive assurances that agreed commitments will be honoured, it is to no one's benefit to withdraw these commitments when there is a consensus that this will result in the unnecessary loss of thousands of lives.