Viral Kinetics in Women of Child Bearing Potential with Chronic HBV Following Treatment with Tenofovir Alafenamide or Tenofovir Disoproxil Fumarate = Viral Kinetics in Women of Child Bearing Potential with Chronic HBV Following Treatment with Tenofovir Alafenamide or Tenofovir Disoproxil Fumarate

다국어 초록 (Multilingual Abstract)

Aims: Suppression of the HBV in women of childbearing potential (WOCBP) has important implications in preventing transmission of HBV from mother to infant. Antiviral therapy that reduces HBV DNA to < 2x105 IU/mL at delivery in mothers can substantially reduce the risk of perinatal transmission. We evaluated the viral kinetics of TAF and TDF in WOCBP.
Methods: : In two Phase 3 studies (HBeAg positive and negative patients), 1301 patients (37% female) were randomized (2:1) to receive TAF 25 mg QD or TDF 300 mg QD. All patients were required to have HBV DNA >2x104 IU/mL at screening and serum ALT >2 times AASLD criteria.WOCBP were defined as nonmenopausal females 18 years or older without history of hysterectomy, bilateral oophorectomy, or ovarian failure. For this subanalysis, patients were stratified by baseline HBV DNA levelsand the endpoints were virologic suppression to HBV DNA <29 IU/mL or < 2x105 IU/mL.
Results: 365(76%) female were identified as WOCBP with 118 (32%) having HBV DNA >1x108 IU/mL at baseline. Suppression rates were generally similar between TAF and TDF groups and within viral load strata for HBeAg positive and negative patients. After 12 weeks of treatment with TAF or TDF, 77% of WOCBP with baseline HBV DNA <2x105 IU/mL had full suppression to <29 IU/mL compared to 1% of those at the highest baseline viral load (Figure A). By Week 24, 54% of all WOCBP had achieved complete viral suppression. Of WOCBP with baseline viral load ≥2x105 IU/mL (n=305), 76%, 89%, and 93% achieved viral load reduction to <2x105 IU/mL by Weeks 4, 8, and 12, respectively (Figure B).
Conclusions: After 12 weeks of treatment the majority of WOCBP had HBV DNA to <2x105 IU/mL. In women with higher baseline viral loads, longer treatment duration may be necessary to achieve viral suppression below recommended thresholds.