Medical Costs Associated with Insomnia Treatment with Suvorexant Monotherapy in Japan: Results from a Retrospective Cohort Study Using a Large-Scale Claims Database

BACKGROUND: The association of insomnia treatment with medical costs is not well characterized in Japan, despite the high economic burden of insomnia. OBJECTIVE: The aim of this study was to investigate the impact of suvorexant, the first dual orexin receptor antagonist, on direct medical costs in insomnia patients. PATIENTS AND METHODS: This retrospective cohort study, conducted using a large-scale claims database, included Japanese patients with diagnosed insomnia receiving suvorexant who were treatment naïve or treatment switchers (pre-treated with a different hypnotic and switched to suvorexant). Total medical costs were estimated for 1 year before and after suvorexant initiation; p-values were calculated for the difference in costs. RESULTS: Of the 1730 patients included, 1116 were treatment naïve and 614 were treatment switchers. Switching to suvorexant did not change the total treatment cost (US$4693–US$4692; p = 0.9964). Although treatment-naïve patients on average incurred US$3259 after suvorexant initiation, much of the additional cost was attributed to drugs other than hypnotics in the outpatient setting (US$332; p < 0.0001). While ~ 10% of the additional medical costs in the outpatient setting were attributable to hypnotics in both groups (treatment naïve: US$106, p < 0.0001; treatment switchers: US$115, p < 0.0001), no difference was observed in the inpatient setting. CONCLUSION: Suvorexant as an initial insomnia treatment was associated with higher total medical costs, given the additional burden of initiating treatment and monitoring costs associated with a new insomnia diagnosis. However, despite a switch from another hypnotic, suvorexant did not increase the incremental economic burden. The hypnotic cost remained proportionately low, demonstrating that suvorexant initiation did not raise the cost of insomnia treatment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40801-021-00279-y.