Benefits And Risks Of Antiretroviral Therapy For Perinatal Hiv Prevention

Antiretroviral regimens used for the prevention of mother-to-child transmission of the human immunodeficiency virus (HIV) have evolved over the years. Combination antiretroviral therapy (ART) is currently used for prevention of motherto-child transmission of HIV but has shown more adverse effects compared with regimens containing fewer antiretroviral agents. This randomized trial evaluated the relative efficacy and safety of various proven antiretroviral strategies for prevention of mother-to-child transmission of HIV during pregnancy among asymptomatic HIV-infected women with high CD4 counts. All analyses were done on an intent-to-treat basis.At screening, the median CD4 count was 530 cells/mL(3), and 3% of the women were HBsAg-positive. The rate of early transmission was significantly lower in the combined maternal ART groups than in the zidovudine-alone group (0.5% vs 1.8%; difference, -1.3 percentage points; repeated confidence interval, -2.1 to -0.4). Grade 2 or higher adverse event was seen in women receiving zidovudine-based ART compared with those receiving zidovudine alone (21.1% vs 17.3%, P = 0.008). A higher rate of grade 2 or higher abnormal blood chemical values was observed in women receiving tenofovir-based ART compared with women receiving zidovudine alone (2.9% vs 0.8%, P = 0.03). Lower birth weight (< 2500 g) was more common with zidovudine-based ART (23.0% vs 12.0%, P < 0.001) and tenofovir-based ART than in women receiving zidovudine alone (16.9% vs 8.9%, P = 0.004). Women receiving zidovudine-based ART had more frequent preterm delivery before 37 weeks (20.5% vs 13.1%, P < 0.001) than women receiving zidovudine alone. Women receiving tenofovir-based ART had significantly higher rates of severe adverse pregnancy outcomes (9.2% vs 4.3%, P = 0.02), very preterm delivery before 34 weeks (6.0% vs 2.6%, P = 0.04), and significantly more infant deaths (4.4% vs 0.6%, P < 0.001) than those receiving zidovudine-based ART. A higher rate of HIV-free survival among infants was noted in zidovudine-based ART regimens than tenofovir-based ART, but no significant difference was noted between infants in the group assigned to tenofovir-based ART and those in the zidovudine-alone group. In conclusion, this trial showed that triple-drug ART had lower rates of mother-to-child transmission in HIV-infected women with high CD4 counts compared with zidovudine alone (0.5% vs 1.8%); however, both the ART regimens were associated with higher rates of adverse outcomes than zidovudine alone.