Aim: To evaluate the effects of tenofovir disoproxil fumarate (TDF) use during late pregnancy to reduce hepatitis B virus (HBV) transmission in highly viremic mothers.
Methods: This retrospective study included 45 pregnant patients with hepatitis B e antigen (+) chronic hepatitis B and HBV DNA levels > 10⁷ copies/mL who received TDF 300 mg/d from week 18 to 27 of gestation (n = 21). Untreated pregnant patients served as controls (n = 24). All infants received 200 IU of hepatitis B immune globulin (HBIG) within 24 h postpartum and 20 μg of recombinant HBV vaccine at 4, 8, and 24 wk. Perinatal transmission rate was determined by hepatitis B surface antigen and HBV DNA results in infants at week 28.
Results: At week 28, none of the infants of TDF-treated mothers had immunoprophylaxis failure, whereas 2 (8.3 %) of the infants of control mothers had immunoprophylaxis failure (P = 0.022). There were no differences between the groups in terms of adverse events in mothers or congenital deformities, gestational age, height, or weight in infants. At postpartum week 28, significantly more TDF-treated mothers had levels of HBV DNA < 250 copies/mL and normalized alanine aminotransferase compared with controls (62% vs none, P < 0.001; 82% vs 61%, P = 0.012, respectively).
Conclusion: TDF therapy during the second or third trimester reduced perinatal transmission rates of HBV and no adverse events were observed in mothers or infants.
Keywords: Chronic; Hepatitis B; Reverse transcriptase inhibitors; Tenofovir; Vertical transmission.