Tenofovir potentially effective against vertical hepatitis B transmission
Treatment with tenofovir disoproxil fumarate (TDF) for hepatitis B virus (HBV) infection appears to be safe and effective in pregnancies exhibiting a high viral load, potentially preventing vertical transmission of the disease, according to a meta-analysis.
Researchers searched multiple electronic databases for studies evaluating the efficacy and safety of TDF in preventing vertical transmission of HBV in pregnancy. Inclusion criteria were randomized controlled trials (RCTs) or controlled observational studies enrolling pregnant women monoinfected with chronic HBV (characterized by the presence of HBsAg for >6 months), with high serum HBV-DNA levels >6 log copies/ml before antiviral therapy.
A total of four observational studies and one randomized controlled trial, involving 585 pregnant women and 595 neonates, were included in the final analysis. Pooled data showed that TDF was superior to placebo in terms of reducing vertical transmission in HBeAg-positive chronic hepatitis B (CHB) pregnancies with high serum HBV-DNA levels (odds ratio [OR], 0.21; 95 percent CI, 0.07 to 0.61) at 4 to 12 months, driving down infant HBV DNA seropositivity at delivery (OR, 0.16; 0.07 to 0.37) and delivering less severe flare in maternal alanine aminotransferase (ALT) levels (OR, 0.43; 0.19 to 0.95) during pregnancy. Furthermore, TDF led to a greater improvement in HBV DNA suppression at delivery (OR, 254.46; 28.39 to 2280.79).
There were no significant between-group differences observed in HBeAg seroconversion and ALT normalization, as well as in rates of caesarean section, emergent caesarean section, postpartum haemorrhage, prematurity, congenital malformations, and infant death.
On the other hand, TDF was associated with a greater frequency of treatment-associated adverse events (OR, 2.33; 1.39 to 3.89) and elevated creatinine kinase (OR, 9.56; 1.17 to 78.09) compared with the control treatment.
Available evidence suggests that TDF is effective and safe in preventing vertical transmission of hepatitis B in pregnancies exhibiting a high viral load.
“The limited safety data suggest that there is no increased risk for adverse maternal or foetal outcomes,” researchers said. “[T]herefore, in order to prevent vertical transmission, we conservatively recommend the use of TDF in pregnant women with CHB and who manifest high HBV DNA levels of >2 × 105 IU/mL in the third trimester.”