A prospective and open-label study for the efficacy and safety of telbivudine in pregnancy for the prevention of perinatal transmission of hepatitis B virus infection.

Background & Aims: In the Asia-Pacific region, perinatal transmission of the hepatitis B virus (HBV) is the primary cause of chronic hepatitis B infection. Despite the use of HBIG and HBV vaccination, HBV perinatal transmission (PT) occurs in 10-30% of infants born to highly viremic mothers. We evaluated the efficacy and safety of LTD use during late pregnancy in reducing HBV transmission in highly viremic HBeAg+mothers.

Methods: Two hundred and twenty-nine HBeAg+HBV DNA levels>1.0×10(7) copies/ml mothers received telbivudine 600 mg/day from week 20 to 32 of gestation (n=135) or served as untreated controls (n=94). All infants in both arms received 200 IU of HBIg within 12 h postpartum and recombinant HBV vaccine of 20 μg at 0, 1, and 6 months. HBsAg and HBV DNA results of infants at week 28 were used to determine perinatal transmission rate. All telbivudine treated subjects were registered in the Antiretroviral Pregnancy Registry.

Results: Telbivudine treatment was associated with a marked reduction in serum HBV DNA and hepatitis B e antigen (HBeAg) levels and normalization of elevated ALT levels before delivery. A striking decline of HBV DNA levels started from treatment onset to week 4, and sustained in a low level since week 12. Forty-four (33%) of the 135 telbivudine-treated mothers and none (0%) of the untreated controls had polymerase chain reaction-undetectable viremia (DNA<500 copies/ml) at delivery. Seven months after delivery, the incidence of perinatal transmission was lower in the infants that completed follow-up born to the telbivudine-treated mothers than to the controls (0% vs. 8%; p=0.002). HBV DNA levels were only detectable in HBsAg+infants. No significant differences in anti-HBs levels were observed during postnatal follow-up. No serious adverse events were noted in the telbivudine-treated mothers or their infants.

Conclusions: Telbivudine used during pregnancy in CHB HBeAg+highly viremic mothers can safely reduce perinatal HBV transmission. Telbivudine was well-tolerated with no safety concerns in the telbivudine-treated mothers or their infants on short term follow up. These data support the use of telbivudine in this special population.