Risk of hepatocellular carcinoma in treatment-naïve chronic hepatitis B patients receiving tenofovir disoproxil fumarate versus entecavir in the United States.

Background: Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are the first-line treatment agents for chronic hepatitis B virus (HBV). Recently, whether the degree to which the risk of hepatocellular carcinoma (HCC) may be reduced by ETV vs TDF has been debated. We compared the incidence of HCC among treatment-naïve patients receiving TDF vs ETV in the United States.

Methods: From a large administrative medical claims database of commercially insured patients, we identified 166,933 adults with a diagnosis of chronic hepatitis B and a minimum of 12 months of prior enrolment, of whom 3934 and 6127 initiated ETV and TDF respectively. Fine-Gray hazard regression models incorporating treatment propensity scores (PS) were used to estimate the risk of HCC incidence associated with TDF vs ETV; variables considered for adjustment included demographic characteristics, concomitant medication use and baseline comorbidities, as well as competing events including liver transplantation and medication changes.

Results: After PS weighting, the TDF and ETV groups were well-matched. During the follow-up, 90 patients developed HCC, including 50 receiving ETV and 40 receiving TDF, giving rise to crude incidence rates of 0.62 per 100 person-years (PY) and 0.30 per 100 PY respectively. In PS-weighted, multivariable analysis, TDF was associated with a subdistribution hazard ratio for HCC of 0.58 (95% confidence interval [CI]: 0.38-0.89) compared to ETV. Results were similar when patients ≥40 years and men and women were analysed separately.

Conclusion: Among commercially insured, treatment-naïve patients with chronic hepatitis B in the United States, treatment with TDF was associated with significantly lower risk of HCC than ETV.