Context Antenatal counseling and human immunodeficiency virus (HIV) testing
are not universal in Africa; thus, women often present in labor with unknown
HIV status without receiving the HIVNET 012 nevirapine (NVP) regimen (a single
oral dose of NVP to the mother at the start of labor and to the infant within
72 hours of birth).
Objective To determine risk of mother-to-child transmission of HIV when either
standard use of NVP alone or in combination with zidovudine (ZDV) was administered
to infants of women tested at delivery.
Design, Setting, and Participants A randomized, open-label, phase 3 trial conducted between April 1, 2000,
and March 15, 2003, at 6 clinics in Blantyre, Malawi, Africa. The trial included
all infants born to 894 women who were HIV positive, received NVP intrapartum,
and were previously antiretroviral treatment–naive. Infants were randomly
assigned to NVP (n = 448) and NVP plus ZDV (n = 446). Infants were enrolled
at birth, observed at 6 to 8 weeks, and followed up through 3 to 18 months.
The HIV status of 90% of all infants was established at 6 to 8 weeks.
Intervention Mothers received a 200-mg single oral dose of NVP intrapartum and infants
received either 2-mg/kg oral dose of NVP or NVP (same dose) plus 4 mg/kg of
ZDV twice per day for a week.
Main Outcome Measures HIV infection of infant at birth and 6 to 8 weeks, and adverse events.
Results The mother-to-child transmission of HIV at birth was 8.1% (36/445) in
infants administered NVP only and 10.1% (45/444) in those administered NVP
plus ZDV (P = .30). A life table estimate of transmission
at 6 to 8 weeks was 14.1% (95% confidence interval [CI], 10.7%-17.4%) in infants
who received NVP and 16.3% (95% CI, 12.7%-19.8%) in those who received NVP
plus ZDV (P = .36). For infants not infected at birth
and retested at 6 to 8 weeks, transmission was 6.5% (23/353) in those who
received NVP only and 6.9% (25/363) in those who received NVP plus ZDV (P = .88). Almost all infants (99%-100%) were breastfed
at 1 week and 6 to 8 weeks. Grades 3 and 4 adverse events were comparable;
4.9% (22/448) and 5.4% (24/446) in infants receiving NVP only and NVP plus
ZDV, respectively (P = .76).
Conclusions The frequency of mother-to-child HIV transmission at 6 to 8 weeks in
our 2 study groups was comparable with that observed for other perinatal HIV
intervention studies among breastfeeding women in Africa. The safety of the
regimen containing neonatal ZDV was similar to that of a standard NVP regimen.