Abstract

Nguyen Van Bang, Le Thi Lan Anh, Nguyen Thi Van Anh, Vu Tuong Van, Philippe Halfon and Marc Bourlière

We evaluated effect and safety of lamivudine and tenofovir in late pregnancy for preventing perinatal transmission of hepatitis B virus (HBV) to infants born to highly viremic mothers. A total of 82 pregnant chronic HBsAg(+) women with high viremia (>107 copies/mL) at 32 weeks of gestation were randomly located in 2 groups (lamivudine 100mg or tenofovir 300mg daily for 8 weeks of prepartum to week 4 pospartum). Infants received recombinant HBV vaccine without HBIg and were followed until week 52. We noted a sharp decrease of mean maternal viral load from 5.09 x 108 ± 3.19 x 108 copies/mL at week 32 of gestation to 1.13 x 106 ± 3.91 x 10 6 at labor (p<0.001) with 2 undetectable HBV DNA cases (2.4%). The viral load reduction was stronger in tenofovir-treated mothers than in lamivudine-treated ones (p<0.028), particularly in 4 log10 reduction (p<0.001). At birth, HBsAg was positive in 21/82 (25.6%) and HBV DNA detectable in 7/82 newborns (8.5%). At week 52, HBsAg and HBV DNA was present in serum of 2/82 infants (2.4%). Both tenofovir and lamivudine in late pregnancy showed the same safety and strikingly reduced perinatal transmission of HBV to infants born to highly viremic mothers.