Treatment: HPTN 046 and Nevirapine
Maker: HIV Prevention Trials Network, in collaboration with the University of California, San Francisco; the University of Zimbabwe; and Stanford University
Stage: Phase III expected to begin early 2007

Why It Matters

More than 500,000 children are infected with HIV each year worldwide. Mother-to-child HIV transmission during pregnancy, labor, delivery or breastfeeding is responsible for more than 90 percent of these cases.

In the developing world, where 95 percent of people with HIV infections live, breastfeeding currently accounts for up to 40 percent of infection of infants, or at least 100,000 children a year, says HPTN 046 principal investigator Yvonne Maldonado of Stanford University. At the same time, abstaining from breastfeeding is often fatal for infants in the developing world, because its lack in early infancy can lead to fatal infections. A study in Botswana found "the risk of breastfeeding and getting HIV seems about equivalent to the risk of not getting breastfed and then developing fatal infections," Maldonado explains.

How It Works

HPTN 046 was designed to allow infected mothers to breastfeed their infants while reducing the chances of HIV transmission using the inexpensive, easy-to-use antiviral medicine nevirapine.

During the study, researchers will give more than 1,500 HIV-infected women in Uganda and Zimbabwe a single dose of nevirapine during labor and delivery. Newborn infants in the trial will also receive a single dose. Doses of nevirapine at labor and delivery are a standard regimen and can decrease infection by as much as 50 percent. Subsequent breastfeeding in the first two years of life, however, may cause infection in the majority of those infants who previously avoided it.

To see whether breastfeeding transmission can be stopped, breastfed infants will receive either HPTN 046 or a placebo once a day for the first six months of life, after which they will be rapidly weaned from breast milk. "We know the risk of dying from not breastfeeding drops off dramatically after six months," says Maldonado. "The potential of this intervention and others like it would be to eliminate transmission of HIV by 50 percent or more in children currently at risk for infection."

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