Effect of tenofovir alafenamide vs. tenofovir disoproxil fumarate on hepatocellular carcinoma risk in chronic hepatitis B.

It is unclear whether tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF) is more effective for preventing hepatocellular carcinoma (HCC) development in patients with chronic hepatitis B (CHB). In this study, we compared the effectiveness of these two antiviral agents for preventing HCC. We included treatment-naïve CHB patients undergoing antiviral therapy with TDF only (TDF group) or a TAF-based regimen (TAF group) at three academic teaching hospitals from 2012 to 2019. The TAF group included patients receiving TAF as first-line treatment and patients switching from TDF to TAF. Patients with decompensated cirrhosis or HCC at enrollment were excluded. Cumulative probabilities of HCC were assessed using Kaplan-Meier methodology. In total, 2,117 patients were included: 1,832 in the TDF group and 285 in the TAF group. The annual HCC incidence was not significantly different between TDF and TAF groups: 1.66 vs. 1.19 per 100 person-years [PY], respectively (multivariate analysis: adjusted hazard ratio [HR] 0.774 [reference: TDF group]; p = .438). Male, liver cirrhosis, hepatitis B e antigen negativity, Fibrosis-4 index>3.25 and low albumin were independently associated with a higher risk of HCC. Propensity score-matched and inverse probability of treatment weighting analyses yielded similar results: 1.56 vs. 1.19 per 100 PY, respectively (HR 1.175; p = .708) and 1.66 vs. 1.29 per 100 PY, respectively (HR 0.888; p = .446). The risk of HCC development was not significantly different between TDF and TAF groups of CHB patients. Further studies with a larger sample size and longer follow-up are required to validate our results.