Treatment adherence and virological response rates in hepatitis C virus infected persons treated with sofosbuvir-based regimens: results from ERCHIVES.

BACKGROUND & AIMS: Role of non-adherence upon virological success with newer oral regimens is unknown. We sought to determine the impact of treatment adherence upon virological outcomes in hepatitis C virus (HCV) infected persons on sofosbuvir (SOF)-based regimens, using pharmacy prescription data as a measure of adherence.

METHODS: We analysed HCV infected persons in Electronically Retrieved Cohort of HCV Infected Veterans, who were initiated on SOF-based regimens, excluding those with human immunodeficiency virus, positive hepatitis-B surface antigen, hepatocellular carcinoma and missing HCV RNA.

RESULTS: The final dataset included following regimens: SOF+simeprevir (SIM) (n = 1050), SOF+ledipasvir (LDV) (n = 974), SOF+ribavirin (RBV) (n = 663, genotype 2 or 3), and SOF+pegylated interferon (PEG)+RBV (n = 519, genotype 1 or 4). Those treated with a SOF-based regimen were older and more likely to have cirrhosis, diabetes, chronic kidney disease, higher HCV RNA levels, higher body mass index, compared with 1652 controls receiving a boceprevir-based (BOC) regimen. Sustained virological response (SVR12) rates for the SOF+SIM and SOF+LDV groups did not decline significantly even when as low as 50% of the full course was prescribed (except SOF+LDV, 90-99% prescriptions had SVR12 of 84.6%; n = 13). SOF+RBV for genotype 2/3 who received 50-80% of the prescriptions, 23/34 (67.6%) achieved SVR12. For persons with genotype 1/4 infection treated with SOF+PEG+RBV, no declines in SVR12 were seen with lower rates of prescriptions (40/43, or 93% SVR12 rate).

CONCLUSIONS: Sofosbuvir-based treatment regimens are highly effective in achieving SVR12. This efficacy is not significantly affected when treated persons receive less than a full prescribed course of treatment.