Cost-effectiveness analysis of suvorexant for the treatment of Japanese elderly patients with chronic insomnia in a virtual cohort

This study assessed the cost-effectiveness of the orexin receptor antagonist suvorexant against zolpidem, the most widely used hypnotic benzodiazepine receptor agonist in Japan. To this end, a model was used that factored in insomnia and the risk for hip fractures, which have devastating effects on the elderly.Data were derived from published papers. The target population was a virtual cohort of elderly patients (≥65 years) with insomnia residing in Japan. Cost-effectiveness was evaluated using quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio as effectiveness measures. The investigators assumed the perspective of healthcare payers.In the base-case analysis, suvorexant was cost-saving (suvorexant: $252.3, zolpidem: $328.7) and had higher QALYs gained (suvorexant: 0.0641, zolpidem: 0.0635) for elderly Japanese patients with insomnia compared with zolpidem, indicating that suvorexant was dominant. In the sensitivity analysis, the outcome changed from dominant to dominated due to the relative risk for hip fractures associated with suvorexant. However, when the other parameters were varied from the lower to the upper limits of their ranges, suvorexant remained dominant compared to zolpidem.The relative risk for hip fractures for suvorexant used in the model was based on data from pre-approval clinical trials. More precise data may be needed.Suvorexant seemed to be more cost-effective than the alternative zolpidem. The findings suggested that suvorexant might be a viable alternative to zolpidem for elderly patients with insomnia. A sensitivity analysis showed that outcome varied depending on the relative risk for hip fractures associated with suvorexant. Further investigations may be needed for more precise results.