Findings presented at the annual Liver Meeting sponsored by the American Association for the Study of Liver Diseases revealed that there was no discernible difference in the incidence of congenital abnormalities among newborns, at 3.1% in the early group and 6.4% in the late group (P=0.22).
The chronic HBV infection threatens the health of roughly 296 million people worldwide.
The World Health Organization (WHO) advises using TDF in conjunction with baby HBV immunisation, HBIg, and maternal usage of TDF for mothers who have HBV DNA levels more than 200,000 IU/mL. The researchers investigated whether earlier maternal TDF and newborn immunisation, but without HBIg, could equally protect against mother-to-child HBV transmission due to the dearth of HBIg in many underdeveloped countries. The vertical transmission rate was zero in a prior study conducted in Cambodia using a similar approach.
A randomised experiment carried out in China discovered that early maternal tenofovir disoproxil fumarate (TDF) combined with newborn vaccination prevented the vertical transmission of chronic hepatitis B virus (HBV) from highly viremic mothers, even without the use of hepatitis B immunoglobulin (HBIg).
Calvin Pan, MD, of the NYU Langone Health in New York City reported that mother-to-child transmission at 28 weeks postpartum was an identical 0% with early maternal TDF therapy starting at 14-16 weeks gestational age (followed by infant HBV vaccination) versus maternal TDF therapy starting at 28 weeks gestational age (followed by infant vaccination plus HBIg). At delivery, more mothers in the early TDF group had HBV-DNA levels below 200,000 IU/mL (99% vs 94%, P=0.04) and considerably lower HBV-DNA levels (2.37 vs 3.62 log10 IU/mL, P0.001).
Findings presented at the annual Liver Meeting sponsored by the American Association for the Study of Liver Diseases revealed that there was no discernible difference in the incidence of congenital abnormalities among newborns, at 3.1% in the early group and 6.4% in the late group (P=0.22).
The exploratory arm’s findings, according to Pan, demonstrated that starting TDF at week 16 of gestation might effectively prevent transmission, which is comparable to the current standard of care, with no safety concerns, when combined with newborn immunisation.
According to William Carey, MD, of the Cleveland Clinic in Ohio, the current study used the fact that HBIg is in little supply to create a novel and simple technique by completely removing HBIg. Carey, who was not engaged in the study, stated that anything that can be done to make the process of protecting [a] newborn simpler would be appreciated.
Investigators enrolled 265 mothers who had chronic HBV (and HBV DNA levels > 200,000 IU/mL) who gave birth to 269 children between June 2018 and February 2021. TDF was administered daily at a dose of 300 mg. We administered active immunoprophylaxis to all newborns. Being positive for HBV surface antigen (HBsAg) or having HBV-DNA levels above 20 IU/mL were used to define mother-to-child transmission.
Reached for comment, Andrew Talal, MD, MPH, of the University at Buffalo in New York, told MedPage Today that further studies “should investigate this approach to determine the generalizability of these findings to other populations.”
“It is important to recognize that this is a very small sample size, inadequate to determine potential harms that occur infrequently,” Carey explained. “If confirmed, it is likely that the two-step strategy will become common practice.”
Both modified intention-to-treat and per-protocol analyses produced identical primary outcome outcomes, and a sensitivity analysis revealed a 2% mother-to-child transmission rate within the early TDF group, showing equal efficacy to the current standard of care. The average age and BMI of the mothers in the research were 28 and 22, respectively.
According to Pan, TDF medication was well tolerated, and no patients stopped receiving it due to serious side effects (AEs). He noted that safety parameters such severe adverse events (AEs), glomerular filtration rates throughout therapy, and postpartum alanine aminotransferase (ALT) flares were present in both groups with comparable frequency and severity.
The lack of a placebo and the brief follow-up were two study drawbacks. According to Pan, four infants in the initial group received HBIg.
Parvathy Sukumaran 
