[Efficacy and safety profile of TAF and TDF in vertical transmission of hepatitis B virus].

<b>Objective:</b> To retrospectively compare the efficacy and safety profile of tenofovir alafenamide fumarate (TAF) and tenofovir disoproxil fumarate (TDF) for interrupting mother-to-child transmission of hepatitis B virus (HBV). <b>Methods:</b> A retrospective study was conducted on 97 cases of HBV-infected pregnant women. Pregnant women were divided into the TDF group (300 mg/d, <i>n</i>=54) and the TAF group (25 mg/d, <i>n</i>=43) and were followed up until seven months postpartum. Statistical analysis was analyzed using t-test, analysis of variance, Bonferroni test, Mann-Whitney <i>U</i> test, or <i>χ</i>² test according to different data. <b>Results:</b> A total of 43 and 54 pregnant women received TAF and TDF treatment. There were 43 and 54 live births, respectively. Both TAF and TDF groups of pregnant women did not discontinue treatment due to adverse events. There was no statistically significant difference in alanine aminotransferase, aspartate aminotransferase, serum creatinine, and uric acid before and after treatment between the two groups. There were no outbreaks of hepatitis during treatment and follow-up among mothers in both groups. The average serum HBV DNA viral load was significantly reduced before and after treatment in both groups, and the difference was statistically significant (TAF: <i>F</i>=40.33, <i>P</i><0.001, TDF: <i>F</i>=97.77, <i>P</i><0.001), but there was no statistically significant difference in the degree of reduction between both groups (<i>P</i>>0.05). The HBeAg seronegative rates were 0.250, 0.704, and 3.743 at 28 to 32 weeks of gestation, at delivery, and seven months postpartum among pregnant women in both groups, with no statistical significance (<i>P</i>>0.05). Compared with the TDF, the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in pregnant women in the TAF group at 28 to 32 weeks of gestation and delivery were increased, and the difference between both group was statistically significant (<i>P</i><0.05). Compared with the baseline level, the median LDL-C level increased significantly at seven months postpartum, while the TC, TG, and HDL-C levels returned to normal, and the difference was statistically significant (<i>P</i><0.05). There were no reports of congenital malformations or defects in all newborns at birth. The growth parameters (height, weight, head circumference) of all infants at seven months of age were within the normal range. There was no statistically significant difference between the TAF and TDF groups (<i>P</i>>0.05). The HBV DNA levels of mothers were significantly lower in both groups than the baseline during the treatment period, and there was no statistically significant difference in the magnitude of reduction between both group (<i>P</i>>0.05). All infants received HBV immunoprophylaxis, and the MTCT rate was 0. <b>Conclusion:</b> The use of TAF in the second trimester of pregnancy has a strong curative effect and can effectively reduce the rate of mother-to-child transmission. However, the use of TAF can cause an increase in blood lipid levels, especially with a more significant impact on LDL-C.