UC San Diego

Background and aims

Chronic hepatitis B (CHB) can lead to hepatocellular carcinoma (HCC). While both tenofovir disoproxil (TDF) and entecavir (ETV) have been shown to reduce the risk of HCC, their comparative effectiveness is unclear. We estimated the comparative effectiveness of these two agents in reducing the risk of HCC in patients with CHB, through a systematic review and meta-analysis.

Approach and results

We searched multiple electronic databases from January 1, 1998, to October 31, 2019, for randomized controlled trials and observational comparative effectiveness studies in adults with CHB treated with ETV compared to TDF, reporting the incidence of HCC (minimum follow-up 12 months). Primary outcome was incidence of HCC, calculated as incidence rate ratio (IRR) with 95% confidence interval (CI, unadjusted analysis) and hazard ratio (HR) with 95% CI (adjusted analysis, where reported). Of 1,971 records identified, 14 studies (263,947 person-years) were included for quantitative analysis. On unadjusted meta-analysis of 14 studies, the risk of HCC was not statistically different between ETV and TDF (IRR, 1.28; 95% CI, 0.99-1.66). When using available adjusted data (multivariate or propensity-matched data), the risk of HCC among patients treated with ETV was 27% higher when compared to TDF (seven studies; 95% CI, 1.01-1.60, P = 0.04). Additional analysis of adjusted data when separately reported among patients with cirrhosis demonstrated an adjusted HR of 0.90 (95% CI, 0.66-1.23), suggesting no difference between ETV-treated and TDF-treated groups. The overall confidence in estimates was very low (observational studies, high heterogeneity).

Conclusions

TDF may be associated with lower risk of HCC when compared to ETV.