Short-course oral zidovudine for prevention of mother-to-child transmission of HIV-1 in Abidjan, Côte d'Ivoire: a randomised trial.

Background: In Africa, the risk of mother-to-child transmission of HIV-1 infection is high. Short-course perinatal oral zidovudine might decrease the rate of transmission. We assessed the safety and efficacy of such a regimen among HIV-1-seropositive breastfeeding women in Abidjan, Côte d'Ivoire.

Methods: From April, 1996, to February, 1998, all consenting, eligible HIV-1-seropositive pregnant women attending a public antenatal clinic in Abidjan were enrolled at 36 weeks' gestation and randomly assigned placebo or zidovudine (300 mg tablets), one tablet twice daily until the onset of labour, one tablet at onset of labour, and one tablet every 3 h until delivery. We used HIV-1-DNA PCR to test the infection status of babies at birth, 4 weeks, and 3 months. We stopped the study on Feb 18, 1998, when efficacy results were available from a study in Bangkok, Thailand, in which the same regimen was used in a non-breastfeeding population.

Findings: 280 women were enrolled (140 in each group). The median duration of the prenatal drug regimen was 27 days (range 1-80) and the median duration of labour was 7.5 h. Treatment was well tolerated with no withdrawals because of adverse events. All babies were breastfed. Among babies with known infection status at age 3 months, 30 (26.1%) of 115 babies in the placebo group and 19 (16.5%) of 115 in the zidovudine group were identified as HIV-1 infected. The estimated risk of HIV-1 transmission in the placebo and zidovudine groups were 21.7% and 12.2% (p=0.05) at 4 weeks, and 24.9% and 15.7% (p=0.07) at 3 months. Efficacy was 44% (95% CI -1 to 69) at age 4 weeks and 37% (-5 to 63) at 3 months.

Interpretation: Short-course oral zidovudine was safe, well tolerated, and decreased mother-to-child transmission of HIV-1 at age 3 months. Substantial efforts will be needed to ensure successful widespread implementation of such a regimen.