A Real-World Study on Safety and Efficacy of TAF Treatment in HBV Patients with High Risk of Osteoporosis or Osteopenia in China.

Long-term antiviral treatment is necessary for chronic hepatitis B (CHB) patients, and treatment safety is imperative for these patients. Previous studies showed tenofovir alafenamide (TAF) has shown efficacy non-inferior to that of tenofovir disoproxil fumarate (TDF) with improved renal and bone safety. However, there is still a lack of a rapid and convenient method to identify CHB patients at high risk of osteoporosis before initiating antiviral treatment. The International Osteoporosis Foundation (IOF) recommended a one-minute osteoporosis risk test to identify early high-risk patients. Our aim was to evaluate the feasibility of the one-minute osteoporosis risk test, along with evaluating the effectiveness and safety for virologically suppressed CHB patients switching to TAF.In this multicenter, prospective study, patients with chronic HBV infection who had been receiving TDF or Entecavir (ETV) for 48 weeks or more with HBV DNA less than 20 IU/mL for longer than 6 months were screened by one-minute osteoporosis risk test. Patients with a high risk of osteoporosis and then diagnosed with osteopenia or osteoporosis by dual-energy X-ray absorptiometry (DEXA) were enrolled. Safety in bone and bone turnover markers and antiviral efficacy of TAF were assessed respectively at 24 and 48 weeks.84.95% (175/206) CHB patients screened by one-minute osteoporosis risk test were at risk of osteoporosis.85.71% (150/175) were diagnosed with osteopenia by DEXA. The analysis included a total of 138 patients, of whom 92(62.3%) were male and 46 (37.7%) were female, with a mean age of 45 years old. HBV DNA was suppressed at 48 weeks at 88% (35/40) in the prior ETV group and 90% (88/98) at 48 weeks group in the prior TDF group. Bone mineral density (BMD) of the lumbar spine (L1-L4) from TDF switching to TAF was improved at 24 weeks (1.03±0.11 vs. 0.97±0.12, P = .001) than baseline. Propeptides of type I procollagen (PINP) and beta-C-terminal telopeptides of type 1 collagen (CTX) in serum at 24 weeks after switching from TDF to TAF declined compared with baseline (50.35±18.90 vs. 63.65±19.17, P = .016 and 0.21±0.13 vs. 0.32±0.10, P = .017). BMD, PINP, and CTX in ETV to TAF group remained stable during treatment.Attention should be paid to osteoporosis risk during lone-term nucleot(s)ide analogue treatment. One minute test of osteoporosis risk could rapidly identify most CHB patients at risk of osteoporosis. Given its convenience, we recommend using this test for early screening in CHB patients prior to initiating antiviral treatment. Our results further demonstrated that an improvement in bone safety after switching to TAF in virologically suppressed CHB patients with osteoporosis.