The impact of public coverage of newer hepatitis C medications on utilization, adherence, and costs in British Columbia

BACKGROUND: Sofosbuvir and ledipasvir-sofosbuvir are both newer direct-acting antiviral agents for the treatment of hepatitis C. The high list prices for both drugs have led to concern about the budget impact for public drug coverage programs. Therefore, we studied the impact of public prescription drug coverage for both drugs on utilization, adherence, and public and private expenditure in British Columbia, Canada. METHODS: We used provincial administrative claims data from January 2014 to June 2017 for all individuals historically tested for either hepatitis C and/or human immunodeficiency virus. Using interrupted time series analysis, we examined the impact of public insurance coverage on treatment uptake, adherence (proportion of days covered), and public and private expenditures. RESULTS: Over our study period, 4,462 treatment initiations were eligible for analysis (1,131 sofosbuvir and 3,331 ledipasvir-sofosbuvir, which include 19 patients initiated on both treatments). We found the start of public coverage for sofosbuvir and ledipasvir-sofosbuvir increased treatment uptake by 154%. Adherence rates were consistently high and did not change with public coverage. Finally, public expenditure increased after the policy change, and crowded out some private expenditure. CONCLUSION: Public coverage for high-cost drugs for hepatitis C dramatically increased use of these drugs, but did not reduce adherence. From a health policy perspective, public payers should be prepared for increased treatment uptake following the availability of public coverage. However, they should not be concerned that populations without private insurance coverage will be less adherent and not finish their treatment course.