A cost-effectiveness analysis of second-generation antihistamine 1 receptor blockers and Japanese kampo shoseiryuto for treatment of perennial allergic rhinitis in outpatient settings in Japan

Objectives: Perennial allergic rhinitis (PAR) is common in Japan.
Second-generation antihistamines (SGAs) are commonly used for its
treatment; however, it remains unclear which SGA is the most
cost-effective. Additionally, the pharmacoeconomics of Japanese Kampo
shoseiryuto (which was traditionally prescribed to treat PAR in Japan)
remains poorly understood. In this study, we aimed to investigate the
effectiveness of various SGAs and shoseiryuto for the treatment of PAR in
Japanese outpatients, from the healthcare payer’s perspective. Methods:
The most cost- and clinically effective SGAs were determined from a list
of six SGAs (bepotastine, 10 mg; cetirizine, 10 mg; ebastine, 10 mg;
epinastine, 20 mg; loratadine, 10 mg; and olopatadine, 5 mg) together with
shoseiryuto, using the overall improvement rate through a model-based
analysis. The time horizon was 28 days. Costs were determined based on the
Medical Fee Index in 2020. Deterministic and probabilistic sensitivity
analyses were conducted to address the uncertainty of the base-case
results. Results:
             Overall, bepotastine (10 mg) and ebastine (10 mg) were cost-effective. Shoseiryuto was less cost-effective than ebastine (10 mg) (dominated). Ebastine (10 mg) was the most cost-effective option based on deterministic and probabilistic sensitivity analyses. Conclusions: Ebastine (10 mg) was the most cost-effective treatment strategy for PAR among the agents evaluated in this study. This insight could aid in establishing an appropriate formulary for treating PAR in hospitals and communities.