By: Shelagh McNally for Uterus1
One of the most difficult challenges of the AIDS virus is the mother-to-infant transmission. However several new drug trials have been completed using a short and relatively inexpensive combination of HIV drugs with promising results in protecting infants from contracting AIDS from infected mothers. Currently the most commonly used drug for pregnant women with AIDS is nevirapine. It is particularly popular in the Third World because it’s both cheap and highly effective. It’s been the most favored drug since a 2001 study in England demonstrated that nevirapine was 48 percent more effective than AZT (zidovudine) in treating pregnant women with AIDS. The standard treatment has been one dose of nevirapine first given to the infected pregnant women while in labor and then another dose to their newborns. Unfortunately, up to two-thirds of women become resistant to the drug.
|At a Glance:|
More than 40 million people are infected with AIDS and over 3 million will die from the disease.
Nevirapine costs $8 per does and is given to infected pregnant women in a single dose to prevent transmission to their infants.
Two-thirds of pregnant women become immune to nevirapine
New combination of combivir and nevirapine reduces rates of mother-to-infant transmissions to below 5 percent.
Recent studies in Africa in the Ivory Coast and in Botswana gave infected mothers a combination of combivir (which contains the HIV inhibitors AZT and lamivudine also known as 3TC) along with the nevirapine in their 32nd week of gestation, twice a day until delivery. At the birth both mother and infant were given single dose of nevirapine. The infants then continued on a weeklong does of zidovudine and the mothers were given a three days treatment of Combivir. The results showed a dramatically reduced mother-to-child transmission. At six weeks of age, fewer than 5 percent of the newborns were infected while only 1 percent of the mothers had become resistance to resistant to nevirapine, and just 8 percent to 3TC.
“This is one of the lowest transmission rates ever reported in Africa - 4.7%,” said François Dabis, MD, professor of epidemiology, University of Bordeaux, Bordeaux, France, “This is very promising for low-income countries.” Dr. Dabis was part of the original team treating 329 women in Abidjan, Côte d'Ivoire with the new combination of drugs. As a result the World Health Organization is looking at broadening its guidelines to include the new regimen. “For a minimum additional cost, we may get many benefits,” said Dr. James McIntyre, an AIDS researcher in South Africa. However, the new combination would cost double the current $8 for a single dose of nevirapine - a major stumbling block for those countries too poor to even afford nevirapine.
More research is needed, especially to see if the combination can prevent the mother-to-infant transmission that occurs during breast-feeding. Although there is a 1 percent rate of infection to newborns from mothers who breastfeed, doctors are still reluctant to discourage breast-feeding in the Third World, since its benefits still far outweigh those of formula feeding. Dr. Mary Glenn Fowler, MD, chief of maternal-child transmission, Centers for Disease Control and Prevention in Atlanta, said these preliminary results would be followed closely, especially to see if the new combination could help newborns withstand transmission through breastfeeding.