Nevirapine Dosing for Prevention of Mother-to-Child HIV Transmission
The mother should receive a single 200 mg oral dose of nevirapine at the onset of labor, and the infant should receive a single 2 mg/kg oral dose immediately after birth or within 48-72 hours. 1, 2
Maternal Dosing
- Administer nevirapine 200 mg orally as a single dose at the onset of labor 1, 2
- This achieves median maternal plasma concentrations of 1623 ng/ml at delivery, with effective transplacental transfer (cord/maternal blood ratio of 0.75) 3
- Maternal HIV-1 RNA decreases by a median of 1.3 logs within 7 days after a single dose 2, 3
Infant Dosing
- Administer nevirapine 2 mg/kg oral suspension as a single dose immediately after birth or within 48-72 hours 1, 2
- Giving the dose as soon as possible after birth is critical for maximum effectiveness—many prevention programs find immediate administration more practical than waiting until 48-72 hours 2
- The prolonged neonatal elimination half-life (median 46.5-54 hours) maintains therapeutic concentrations above 100 ng/ml throughout the first week of life 4, 3
Enhanced Regimen for High-Risk Scenarios
When the mother received no antiretroviral therapy during pregnancy or labor, combination therapy is superior to nevirapine alone:
- Infant regimen: Nevirapine 2 mg/kg single dose at birth PLUS zidovudine 4 mg/kg orally twice daily for 6 weeks 2, 5
- Zidovudine must be initiated within 6-12 hours of birth for optimal effectiveness 2, 6
- This combination reduces transmission more effectively than single-dose nevirapine alone (transmission rates of 15.3% vs 20.9% at 6-8 weeks) 2
Clinical Efficacy Evidence
- The HIVNET 012 trial demonstrated that single-dose nevirapine reduced transmission by nearly 50% compared to short-course zidovudine (12% vs 21% at 6 weeks) in breastfeeding populations 1, 7
- In non-breastfeeding populations, adding nevirapine to short-course zidovudine provides superior efficacy compared to either agent alone 1
Critical Implementation Points
- Nevirapine crosses the placenta effectively, achieving neonatal blood concentrations equivalent to maternal levels 2
- Breast milk concentrations reach 60.5% of maternal plasma levels, with median concentrations of 103 ng/ml at 1 week postpartum 3
- No serious adverse events related to nevirapine were observed in multiple studies involving hundreds of mother-infant pairs 2, 3
Common Pitfalls to Avoid
- Do not use single-dose nevirapine monotherapy in resource-rich settings—it carries a 19% risk of resistance mutations at 6 weeks postpartum and is inferior to combination therapy 2
- Do not add nevirapine to women already receiving adequate antiretroviral therapy—this provides no additional benefit (1.4% vs 1.6% transmission) and increases resistance risk 2
- Do not delay zidovudine initiation beyond 48 hours when combination therapy is indicated—transmission rates increase from 9% to 18% with delayed initiation 2, 6