April 10, 2002
The study's aim was to find out the most effective way of administering two common antiretrovirals, zidovudine and lamivudine. Researchers conducted a randomized trial among 1,797 pregnant women with HIV in Tanzania, South Africa and Uganda who were divided into four groups. The first group received the two drugs as therapy before delivery, during labor and after the child's birth. The second received it during labor and after delivery. The third group was given the treatment only during labor, while the forth group was given a placebo.
Six weeks after birth, 5.7 percent of newborns in the first group had HIV; the rates in the other groups were 8.9 percent, 14.2 percent and 15.3 percent respectively. But, regardless of the group, the infection rate then soared because mothers were passing on the virus in their breast milk. After 18 months, infection rates were 15 percent, 18 percent, 20 percent and 22 percent respectively. The PETRA study was conducted in 1998 and sparked a fierce debate about medical testing in developing countries, centering on the placebo that was given to the fourth group of women.
Wealthy countries provide HIV-infected mothers with a long course of these drugs, before birth and for many weeks after the mother is breastfeeding. However, African countries are limited by funds and can afford only the short course of treatment that focuses on labor and delivery. Lead researcher Joep Lange of the University of Amsterdam said that the first treatment regimen was clearly the most beneficial for infants at risk of catching HIV from their mothers. He recommended that a third antiretroviral agent, commonly used in rich countries, be added to the dual drug mix.