OBJECTIVES: Opioid substitution treatment (OST) in Sweden is unique among European countries for having a strict policy for illicit drug use while receiving OST, and largely excluding prescription opioid abusers from methadone- or buprenorphine-based OST (i.e., focusing on heroin-abusers). Heroin abuse is a risk factor for increased healthcare utilization, criminality, and overdose death: risks that are magnified by OST discontinuation. A recent, 24-week, Phase-3 clinical trial enrolling primarily heroin-dependent subjects demonstrated superior efficacy of flexible-dose depot buprenorphine (CAM2038) versus sublingual buprenorphine/naloxone (SL-BPN) in cumulative illicit opioid use. The present analysis was conducted to estimate the associated economic impact of CAM2038 from a Swedish perspective.

METHODS: Annual direct medical costs (excluding OUD treatment costs), societal costs, and quality-adjusted life years were assessed using a 5-state Markov model wherein cohorts received CAM2038 or SL-BPN. Transition probabilities were derived from the Phase-3 trial. State-specific event probabilities and associated costs/utilities were literature-based. Uncertainty was evaluated with scenario and probabilistic sensitivity analysis.

RESULTS: Annual total costs were 21% lower for CAM2038 vs SL-BPN in the most conservative scenario. Approximately 83% of these cost-savings were attributable to reduced criminality/victimization costs. Reduced emergency and hospital services primarily drove direct-medical cost-savings. Outcomes were sensitive to rules for how the frequency/pattern of on-treatment illicit opioid use triggered forced discontinuation and to rules regarding the minimum-allowable time to OST reengagement.

CONCLUSIONS: OST with CAM2038 for opioid-dependent adults is estimated to lower direct-medical and societal costs in Sweden. Scenario analyses were relevant for Sweden where clinicians autonomously set discontinuation and reengagement rules. The pharmacoeconomic benefits of CAM2038 in Sweden may be more pronounced than in other European countries given relatively high costs associated with heroin addicts discontinuing OST.