Progress in prevention of perinatal HIV-1

The findings of a recent human immunodeficiency (HIV-1) prevention trial in the USA demonstrated that administration of an antiretroviral drug, zidovudine, to mothers during the prenatal and intrapartum periods, and to their neonates for 6 weeks, resulted in a two-thirds reduction in risk of perinatal transmission from 25.5% to 8.3%. These results were rapidly disseminated both in the USA and internationally. Since the release of these clinical trial results in the spring of 1994, several observational studies have documented a sharp increase in maternal and neonatal zidovudine use, as well as a significant decrease in perinatal HIV-1 transmission, with rates of about 8% being observed in non-clinical trial settings. Internationally, the results have led to the development of a variety of perinatal prevention trials that build on the success of the U.S. perinatal prevention trial but use modified strategies that can feasibly be carried out in developing countries.