The results of the South African Intrapartum Nevirapine Trial (SAINT), published in this issue of The Journal of Infectious Diseases provide further evidence of the safety and efficacy of short-course antiretroviral prophylaxis regimens for the prevention of mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV). SAINT compared 2 intrapartum/postpartum antiretroviral regimens, multiple-dose zidovudine/lamivudine and single-dose nevirapine, that had been shown in previous, separate clinical trials to be effective in preventing MTCT and found that both regimens had similar efficacy and safety. SAINT is the fifth clinical trial in breast-feeding populations published since 1999 that has demonstrated the safety and efficacy of different short-course antiretroviral regimens for preventing MTCT. However, the results of these trials appear to have had little impact on the perinatal HIV epidemic in resource-limited countries, bringing into sharp focus the differences in the perinatal epidemic between resource-rich countries and those with limited resources
It has been less than a decade since the Pediatric AIDS Clinical Trials Group (PACTG) protocol 076 demonstrated the efficacy of a 3-part antenatal, intrapartum, and 6-week infant zidovudine regimen in prevention of MTCT, initiating major changes in the perinatal HIV epidemic in resource-rich countries. Ten years ago, ∼6000 HIV-infected women gave birth each year in the United States, and ∼1600 of their infants became HIV-infected through MTCT annually. Within 1 year of the publication of the results from PACTG 076, widespread implementation of the zidovudine prophylactic regimen, coupled with recommendations for universal prenatal HIV counseling and voluntary testing, resulted in a decrease in transmission from ∼25% to 8% in this country. More recently, with the use of highly active antiretroviral therapy and elective cesarean delivery, transmission rates have decreased to <2%, and it is estimated that
What accounts for the dramatic and rapid success in reducing MTCT in resource-rich countries? The availability of a highly effective regimen that reduced perinatal transmission by nearly 70% without excess toxicity to the mother or the infant was clearly a key element. But without widespread incorporation of this regimen into clinical practice, no population-wide effect would have occurred. After the release of the results of PACTG 076, the US Department of Health and Human Services rapidly convened a Public Health Service task force to review the trial results; the task force published guidelines within 6 months for broad use of this regimen and soon thereafter for universal voluntary HIV counseling and testing for pregnant women. In addition, in the United States, the almost universal availability of clean water, government programs to subsidize the purchase of formula for women living in poverty, and cultural acceptability of formula feeding have allowed HIV-infected women to avoid breast-feeding, thereby preventing postnatal transmission of HIV.