Trenton, N.J. — Pharmaceutical manufacturer Merck & Co. announced that it will drastically cut prices for two HIV drugs in AIDS-ravaged Africa and other developing parts of the world.

In a statement Wednesday, the company said it will make no profit when selling the two protease-inhibitor drugs in developing countries. The drugs will be made available at about one-tenth of their U.S. price.

Merck and other drug companies have come under sharp criticism from various governments and relief groups, which accuse them of keeping patented lifesaving medicines beyond the reach of the world's poor.

"The reason we did this is we're trying to speed the process of access to these medicines," said Merck spokesman Greg Reaves. "We thought it would now spur other entities to get involved."

The announcement comes amid a lawsuit in South Africa filed by a group representing many of the world's leading pharmaceutical companies, including Merck. The lawsuit by the Pharmaceutical Manufacturers' Association seeks to overturn a law that would allow the South African government to import cheap generic medications in an emergency. The pharmaceutical companies say these generics undermine their patents on the drugs.

More than 25 million of the 36 million people infected with HIV live in sub-Saharan Africa, one of the world's most impoverished regions. Developing countries in other areas will be evaluated for the reduced-price program on a case-by-case basis, Mr. Reaves said.

Merck said the treatments will be available at a reduced price to governments, relief agencies and others who can provide them to patients, on the condition that the drugs be used only in the countries where they are sold.

Officials with Doctors Without Borders, the Nobel Peace Prize-winning relief agency, welcomed Merck's announcement but cautioned that the reduced price could still leave the drugs out of reach for many of Africa's AIDS patients.