Medication Nonadherence with Long-Term Management of Patients with Hepatitis B e antigen-Negative Chronic Hepatitis B

Antiviral treatment responses for patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) are well-defined by data from registration trials but may differ from patients seen in community settings where medical adherence is usually not as strictly monitored. The goal of this study was to examine the long-term outcomes of HBeAg-negative patients in a community clinical setting. We performed a cohort study of 189 consecutive treatment-na < ve patients with CHB who were treated with either entecavir (ETV) 0.5 mg daily (n = 107) or adefovir dipivoxil (ADV) 10 mg daily (n = 82) from 2002 to 2009 at two community clinics. All patients were Asians. Both ETV and ADV cohorts had similar median baseline ALT and HBV DNA levels. By year 4, a similar proportion of ETV and ADV patients who remained on monotherapy achieved complete viral suppression (91-96%); however, more patients in the ADV cohort required alternative therapy (27 vs. 5%). No patients in the ETV cohort developed resistance while 18% of the ADV cohort did. Cumulative nonadherence rates were 10 and 12% in ADV and ETV cohorts, respectively. Failure to monotherapy in a community clinical setting is due to both antiviral resistance and patient nonadherence. Medication nonadherence is likely to be a more important contributor to treatment failure than antiviral resistance, especially with new anti-HBV agents such as ETV and tenofovir.