Low-Cost Drug May Slow AIDS in Third World

A cheaper and surprisingly powerful new drug regimen to prevent AIDS virus transmission from mother to child could save as many as 400,000 children’s lives annually in developing countries, researchers reported Wednesday.

Lowering the chances of HIV transmission from infected mothers to their children has been a huge success in the fight against AIDS. But at about $1,000 for a five-month course of AZT, that success has been limited to wealthy countries.

Now, researchers at Johns Hopkins University School of Medicine report that a new drug treatment that requires only two doses of a less expensive AIDS drug may have the potential to extend those benefits around the world for less than $4 per child.

In the study, 645 HIV-infected pregnant women in Uganda received either a short AZT treatment or the experimental drug regimen, which consisted of one dose of a drug called nevirapine followed by an additional dose given to children after birth. The results, released Wednesday by the National Institutes of Health, were dramatic--and unexpected.

“We were hoping that nevirapine would be at least as good as AZT,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, the agency that funded the study. The surprise, he said, came when “it was much better.”

Twenty-five percent of 14- to 16-week-old children born after the AZT treatment were infected, compared with only 13% of infants receiving nevirapine. With 1,400 HIV-infected babies born every day in developing countries, the Johns Hopkins researchers estimate the new drug treatment could save up to 4 million children in 10 years.

“This research provides real hope that we may be able to protect many of Africa’s next generation from the ravages of AIDS,” said Crispus Kiyonga, Uganda’s minister of health.

Transmission of HIV at birth has been largely eliminated in wealthier nations. Infected women in the United States receive a long regimen, taking AZT for about five months of pregnancy, a course that is much too expensive for developing countries.

At a time of controversy about how to offer affordable drugs to such countries, nevirapine appears to provide an alternative to more expensive drug courses. Vice President Al Gore has been in the middle of a debate between those who propose low-cost, generic versions of patented drugs for African countries, and manufacturers of AZT and other established AIDS drugs who argue that this would violate their patents.

Currently, 99% of pregnant, HIV-infected Ugandan women use no drugs at all, according to Dr. Brooks Jackson, vice chairman of pathology at Johns Hopkins, who led the study.

Jackson and his Ugandan colleague, Francis Mmiro of Makerere University, were looking for an affordable alternative that was still effective. Many doctors have proposed and tested scaled-down, cheaper versions of the AZT treatment, but until now, none has met those two criteria with stunning success.

“The real advantage here [with nevirapine] is, unlike other studies that have been done to date, this is the first that really overcomes the cost barriers,” Jackson said.

For the two doses, the list price was $3.67. Even with Ugandan per-capita medical spending as low as $7 a year, Jackson felt this cost could be borne. Fauci added that the price might also attract subsidization by charitable organizations that previously didn’t think they could make a difference.

One reason for the low cost, according to Jackson, is that although an equally small dose of AZT would be comparable in price, it would have no therapeutic effect. AZT must be administered in far greater quantities and, hence, at far greater cost.

In addition to its low cost and surprising effectiveness, the nevirapine had other advantages. Nevirapine treatment, Fauci said, “matches the health care delivery system in developing countries,” where there is generally very little prenatal care. “The women come in later, when they are about to go into labor,” which is when the first dose of nevirapine is administered, he added.

In fact, it has been suggested that in the absence of AIDS counseling, the drug could be administered to all women giving birth in areas with a high infection rate, even if they have not been diagnosed with the virus. In such high-risk locales, Jackson said, this is a reasonable idea “more cost-effective than treating infected children.”

Another practical advantage is that the drug can be stored safely in hot climates.

The study results are preliminary, the researchers note. To fully address the safety and efficacy of the drug, they intend to continue observing the children until 18 months of age. So far, though, there have been no serious side effects for children or mothers.

Researchers also point to the unknown effects of breast-feeding. Jackson estimates that breast-feeding--practiced by most Ugandan women for up to two years--can add a 10% to 15% risk for HIV transmission.

Pregnant women on the AZT therapy are generally advised against breast-feeding, but women in developing countries often have no alternatives. No studies have addressed ways to reduce the risk of transmission through breast-feeding, he said.