Difficulties in assessing HIV-prevention interventions in resource-limited settings by randomized controlled trials (RCT) – The example of prevention of mother-to-child transmission (PMTCT)

Abstract

Testing new interventions to reduce the MTCT risk in resource-limited settings with an RCT faces various challenges. Pregnant and lactating women with an advanced HIV disease require long-term antiretroviral treatment (ART) for their own health, which reduces substantially MTCT risk. For those not eligible for ART, PMTCT interventions from the 3rd trimester with combination ARVs and modified infant feeding practices greatly reduces risk. At present such MTCT-prevention interventions remain too complex to be considered as standard of care in resource-limited settings. However, in an RCT those interventions must be provided to all participants in the control arm. The residual MTCT risk is therefore low (considerably less than 10%), and the sample size needed to demonstrate the benefit of any new intervention is now much larger (at least 1000 mother-infant pairs) than when pioneer MTCT-prevention interventions were developed.