Perinatal Antiretroviral Intensification to Prevent Intrapartum HIV Transmission When Antenatal Antiretroviral Therapy Is Initiated Less Than 8 Weeks Before Delivery

J Acquir Immune Defic Syndr. 2020 Jul 1;84(3):313-322. doi: 10.1097/QAI.0000000000002350.


Introduction: Infants born to women living with HIV initiating combination antiretroviral therapy (cART) late in pregnancy are at high risk of intrapartum infection. Mother/infant perinatal antiretroviral intensification may substantially reduce this risk.

Methods: In this single-arm Bayesian trial, pregnant women with HIV receiving standard of care antiretroviral prophylaxis in Thailand (maternal antenatal lopinavir-based cART; nonbreastfed infants 4 weeks' postnatal zidovudine) were offered "antiretroviral intensification" (labor single-dose nevirapine plus infant zidovudine-lamivudine-nevirapine for 2 weeks followed by zidovudine-lamivudine for 2 weeks) if their antenatal cART was initiated ≤8 weeks before delivery. A negative birth HIV-DNA polymerase chain reaction (PCR) followed by a confirmed positive PCR defined intrapartum transmission. Before study initiation, we modeled intrapartum transmission probabilities using data from 3738 mother/infant pairs enrolled in our previous trials in Thailand using a logistic model, with perinatal maternal/infant antiretroviral regimen and predicted viral load at delivery as main covariates. Using the characteristics of the women enrolled who received intensification, prior intrapartum transmission probabilities (credibility intervals) with/without intensification were estimated. After including the transmission data observed in the current study, the corresponding Bayesian posterior transmission probability was derived.

Results: No intrapartum transmission of HIV was observed among the 88 mother/infant pairs receiving intensification. The estimated intrapartum transmission probability was 2·2% (95% credibility interval 0·5-6·1) without intensification versus 0·3% (0·0-1·6) with intensification. The probability of superiority of intensification over standard of care was 94·4%. Antiretroviral intensification appeared safe.

Conclusion: Mother/infant antiretroviral intensification was effective in preventing intrapartum transmission of HIV in pregnant women receiving ≤8 weeks antepartum cART.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-HIV Agents / administration & dosage*
  • Anti-HIV Agents / therapeutic use*
  • Bayes Theorem
  • Drug Combinations
  • Female
  • HIV Infections / drug therapy*
  • HIV Infections / prevention & control*
  • HIV Infections / transmission
  • Humans
  • Infant, Newborn
  • Infectious Disease Transmission, Vertical / prevention & control*
  • Lamivudine / administration & dosage
  • Lamivudine / therapeutic use
  • Mothers
  • Nevirapine / administration & dosage
  • Nevirapine / therapeutic use
  • Pregnancy
  • Pregnancy Complications, Infectious / drug therapy
  • Thailand
  • Viral Load
  • Young Adult
  • Zidovudine / administration & dosage
  • Zidovudine / therapeutic use


  • Anti-HIV Agents
  • Drug Combinations
  • lamivudine, zidovudine drug combination
  • Lamivudine
  • Zidovudine
  • Nevirapine