Effect of relaxing hepatitis C treatment restrictions on direct-acting antiviral use in a Medicaid program: an interrupted time series analysis

BACKGROUND: Although direct-acting antivirals (DAA) have revolutionized the treatment of chronic hepatitis C virus (HCV), many state Medicaid programs have limited coverage because of their expense. In 2015, the Centers for Medicare & Medicaid Services (CMS) notified states about the legality of Medicaid coverage limitations, particularly within managed care programs. OBJECTIVES: To (1) examine how relaxation and alignment of hepatitis C policies within the Oregon Medicaid program affected DAA utilization and (2) describe changes in DAA coverage policies and patient characteristics of treated individuals over time. METHODS: We manually collected DAA Medicaid drug policies in the state of Oregon before and after the CMS notification was released. After categorizing DAA policies into 2 groups based on baseline prior authorization criteria (restrictive and permissive), we evaluated how changes in these DAA policies affected utilization over 3 time periods (pre-CMS period, post-CMS period, and fibrosis policy alignment). Immediate and gradual changes in trend were assessed using an interrupted time series regression model. Finally, we examined patient characteristics and liver disease complications over time as policy restrictions were removed and aligned with one another. RESULTS: From 2014 to 2018, Oregon’s coordinated care organizations and fee-for-service drug policies relaxed liver fibrosis and substance abstinence coverage criteria leading to immediate increases in DAA use in 2016 (0.62 prescriptions per 10,000 enrollees per month; 95% CI = 0.17 to 1.08) and 2018 (1.07 prescriptions per 10,000 enrollees per month; 95% CI = 0.63 to 1.51) among more restrictive coordinated care organizations at baseline. This was followed by a decrease in trend after the 2016 and 2018 impact (−0.05; 95% CI = −0.11 to −0.001 and −0.07; 95% CI = −0.13 to −0.02, respectively). Over the 3 periods, there was a decrease in treated individuals with liver-related complications (P < 0.0001) and an increase in those with a substance use diagnosis (P = 0.0013). CONCLUSIONS: Reducing coverage limitations resulted in treatment of patients with fewer liver-related complications and more substance use disorders. Expanding access to treatment did not result in sustained increases in utilization, and additional interventions may be necessary to meet HCV elimination goals.