There was no significant effect of maternal tenofovir disoproxil fumarate (TDF) use for the prevention of mother-to-child transmission of hepatitis B virus (HBV) on bone mineral density in either the mother or child 1 year after delivery, according to a brief report published in Clinical Infectious Diseases.
In this secondary end point analysis of a randomized, double-blind, multicenter clinical trial conducted in Thailand (iTAP; ClinicalTrials.gov identifier: NCT01745822), women with chronic HBV infection who received either TDF or placebo from 28 weeks gestational age to 2 months postpartum and breastfed their infants were invited to participate in a bone mineral density assessment 1 year after delivery.
During the bone mineral density assessment study, participants, investigators, operators, and dual-energy X-ray absorptiometry specialists were blinded to the treatment group. Total hip bone mineral density in mothers and lumbar spine bone mineral density in both mothers and infants were the main outcome measures.
The study included 135 mother-infant pairs (69 TDF, 66 placebo), 5 singleton mothers (2 TDF, 3 placebo), and 2 singleton infants (1 TDF, 1 placebo). After taking into account invalid measurements resulting from movement or improper positioning, hip bone mineral density measurements were valid in 129 mothers (64 TDF, 65 placebo) and lumbar spine bone mineral density measurements were valid in 138 mothers (71 TDF, 67 placebo) and 115 infants (62 TDF, 53 placebo).
Results showed no significant differences between TDF and placebo groups in maternal hip bone mineral density (mean difference, 0.008 g/cm2; 95% CI, −0.028 to 0.044; P =.67), maternal lumbar spine bone mineral density (mean difference, 0.010 g/cm2; 95% CI, −0.026 to 0.046; P =.59), or infant lumbar spine bone mineral density (mean difference, −0.006 g/cm2; 95% CI, −0.019 to 0.007; P =.38). Sensitivity analysis yielded similar results.
Researchers noted that as the study provided information on women with HBV mono-infection and their infants, the results should not be extrapolated to other populations, such as individuals who are HIV monoinfected or HIV/HBV co-infected.
“TDF prophylaxis to prevent mother-to-child transmission of HBV in HBV-monoinfected women in Asia appeared safe with regard to bone mineralization for both mothers and infants,” concluded the researchers.
Salvadori N, Fan B, Teeyasoontranon W, et al. Maternal and infant bone mineral density 1 year after delivery in a randomized, controlled trial of maternal tenofovir disoproxil fumarate to prevent mother-to-child transmission of hepatitis B virus [published March 29, 2019]. Clin Infect Dis. doi:10.1093/cid/ciy982