Factors Associated with Adherence to First-line Antiviral Therapy among Commercially Insured Patients with Chronic Hepatitis B

Abstract

Background. Nonadherence to antiviral therapy can lead to poor clinical outcomes among patients with chronic hepatitis B (CHB). We used a claims database to evaluate risk factors for nonadherence to antiviral therapy among commercially insured patients with CHB in the United States. Methods. We obtained data for commercially insured adult patients with CHB prescribed entecavir or tenofovir disoproxil fumarate (TDF) in 2019. Primary outcomes were adherence to entecavir and adherence to TDF. Enrollees with a proportion of days covered (PDC) ≥80% were considered adherent. We presented adjusted odds ratios (AORs) from multivariate logistic regressions. Results. Eighty-three percent (n = 640) of entecavir patients were adherent, and 81% (n = 687) of TDF patients were adherent. Ninety-day supply (vs 30-day supply; AOR, 2.21; P < .01), mixed supply (vs 30-day supply; AOR, 2.19; P = .04), and ever using a mail order pharmacy (AOR, 1.92, P = .03) were associated with adherence to entecavir. Ninety-day supply (vs 30-day supply; AOR, 2.51; P $25 per 30-day supply of TDF was associated with reduced odds of adherence to TDF (vs < .01). Conclusions. Ninety-day and mixed-duration supplies of entecavir and TDF were associated with higher fill rates as compared with 30-day supplies among commercially insured patients with CHB.