Progress in reducing mother-to-infant HIV transmission.

Results of five studies evaluate treatments for reducing perinatal transmission of HIV. Pediatric trial ACTG 185 evaluated AZT plus two types of immunoglobulin given beginning at 20-30 weeks gestation. Results showed that mothers with low CD4 counts, or who started therapy with AZT during gestation, had a lower incidence of transmission. Trials in Thailand tested 3 regimens of AZT which were given from 36 weeks gestation through delivery, with no breastfeeding. The transmission rate was 51 percent lower than in the placebo arm of the trial. A comparable trial in a breastfeeding population in the Ivory Coast showed a 44 percent decrease in transmission to infants at 4 weeks of age. The UNAIDS-sponsored PETRA study, administered in three African countries, compared three treatment regimens of AZT and 3TC and a placebo. The researcher found that short course combination therapy for the mother during labor and for the infant in the first week of life was as effective as a longer treatment regimen. However, breastfeeding may eventually alter transmission, and the expense of the regimen makes it inaccessible to women in poor countries. Nevirapine, given as a single dose to the mother at the onset of labor with or without a single dose given to the infant within 72 hours of birth, is an alternative to these drugs. A recent study of Nevirapine in Uganda (HIVNET 006) showed significant declines in plasma HIV levels, and the cost for treating both mother and baby was affordable. Despite these advances, there is a great need for effective and affordable regimens in developing countries.