Reducing Vertical Transmission of Hepatitis B in Africa

The REVERT-B trial is a multi-center, phase III, randomized 2x2 factorial study designed to test the efficacy of early maternal TDF vs standard duration and neonatal 3TC prophylaxis compared to matching placebo in preventing HBV MTCT. Eligible pregnant women with HBV in prenatal care (n=450) will be randomized 1:1:1:1 to one of four maternal and neonatal prophylaxis combinations (shown as A-D in the figure below). Women will initiate daily oral TDF early (2nd trimester) or at the standard time per WHO guidelines (3rd trimester) and will continue TDF until delivery. The current WHO standard of care in pregnant women with HBV (EAg+) in Cameroon is TDF prophylaxis from 28 weeks until delivery. Newborns will receive liquid 3TC or matching placebo for the first six months of life to provide coverage until the vaccine series is complete. All infants in the study will be offered the 4-dose HBV vaccine series starting at birth. The 2x2 factorial design allows for two simultaneous studies where we first assess efficacy of early maternal prophylaxis (Aim 1) and secondarily assess efficacy of neonatal prophylaxis (Aim 2). The study endpoint for both aims is the MTCT rate (proportion of infants HBsAg+) at 6-9 months of age. Women and infants will be followed until 6-9 months after delivery and subaims will assess safety and adherence to maternal TDF and neonatal 3TC. Plasma testing will be used to measure medication adherence.