As public pressure mounts for AIDS drugs to be made available to poor countries at an affordable cost, a leading drug company has pledged for the first time to sell its protease-inhibitor therapies to them at cost price.

Merck said last week that it will make Crixivan (indinavir sulphate) — a component of the triple-drug anti-AIDS therapy widely used in the West — available at $600 a year in developing countries. Another antiretroviral agent, Stocrin (efavirenz), is to be sold at $500. Other major drug companies are expected to follow suit.

The move is an attempt to head off mounting criticism over the cost of AIDS drugs in developing countries (see Nature 410, 3; 2001). The announcement came as a court case, brought by 40 drug companies against the South African government, threatened to turn into a public-relations debacle for the companies.

Merck says that developing countries taking up its offer must introduce procedures to prevent the re-exportation of the drugs to the developed world, where their official price is at least an order of magnitude higher.

“Even at these new lower prices, the issue of access is not resolved,” Per Wold-Olsen, president of Merck's human-health business in Europe, the Middle East and Africa, said last week.

Hearings on the legal action, which seeks to block a South African law that would allow the importation of generic copies of patented drugs, opened briefly in South Africa last week, but were adjourned until next month. Kenya is reported to be considering legislation along similar lines.