A Ugandan-U.S. drug study among HIV-infected pregnant women in Africa has found the simplest, cheapest way yet to prevent transmission of the AIDS virus to newborns: a single dose of the new drug nevirapine given both to the mother and the child. "The implications for public health around the world are tremendous," says Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases (NIAID), which funded the trial in Kampala, Uganda. According to the United Nations Program on HIV/AIDS, about 1800 HIV-infected infants are born each day around the world.
A landmark 1994 study had shown that a very intensive treatment with the drug AZT can reduce the percentage of HIV-positive mothers who infect their babies to 8.3%, from about 25% without treatment. But for most of the world, this regimen proved too expensive and cumbersome. Several studies since have shown that shorter courses of AZT (or AZT and the drug 3TC) had a similar impact, yet even these treatments are prohibitively expensive. The new study, conducted by researchers at Uganda's Makerere University and Johns Hopkins University in Baltimore, compared two cheaper regimens, a very limited course of AZT and the newer nevirapine. Like AZT, nevirapine disables HIV's reverse transcriptase enzyme, which the virus needs to copy itself into the host cell's DNA.
Mothers in the AZT group received the drug every 3 hours from the onset of labor until delivery, while infants were given the drug twice daily the first week after birth. In the nevirapine group, researchers simply gave women one dose at the onset of labor and their babies one within 3 days. A safety panel overseeing the trial ended it on Monday when a review of the interim results showed that HIV infected only 13.1% of the babies born to the 310 women in the nevirapine group; in contrast, the 308 women in the AZT group transmitted the virus to 25.1% of their babies (roughly the same as the proportion of untreated women who infect their babies).
The total retail cost of the nevirapine needed to treat both a mother and an infant is about $4, or 70 times less than a short AZT course, according to NIAID. "This has to be an affordable price to any country," says Fauci.