Tenofovir plus hepatitis B immunoglobulin treatment resulted in a rapid HBV DNA load decline in high‑risk pregnant women who missed the optimal time window of antiviral prophylaxis

Background: Tenofovir disoproxil fumarate (TDF) administration in the third trimester for pregnant women with high HBV DNA load has been accepted as a wise practice to prevent mother-to-infant transmission (MTIT). However, for those women who missed the optimal time window of antiviral prophylaxis, this treatment is lacking in the current clinical guidelines. Methods: Forty-eight pregnant women who did not receive antiviral prophylaxis before 28 weeks of gestation were screened and were administrated with TDF plus hepatitis B immunoglobulin (HBIG; TDF+HBIG group) or TDF alone (TDF group). HBV DNA inhibition and the safety profile were compared between two groups. Results: A decline of HBV DNA load was observed in both groups after a short period of treatment, and no infant had MTIT. However, compared with the TDF group, the speed of HBV DNA load decline was more rapid (P=0.002) and a much more striking HBV DNA load decline in the first 4 weeks of treatment was exhibited in the TDF+HBIG group (P=0.001). The percentages of mothers with HBV DNA <4 log₁₀ IU/ml and 3 log₁₀ IU/ml at delivery were both much higher in the TDF+HBIG group than the TDF group (P=0.034 and 0.024, respectively). TDF and HBIG were found to be well-tolerated with no safety concerns in the mothers and their infants. Conclusions: TDF plus HBIG treatment resulted in a rapid HBV DNA load decline in high-risk women who missed the optimal time window of antiviral prophylaxis in pregnancy, which potentially protected infants from HBV infection.