Persistence with topical glaucoma therapy in Japan from the perspective of product, formulation, and patient characteristics: analysis of medical insurance claim data.

BACKGROUND: Glaucoma is the leading cause of irreversible blindness in Japan and constitutes a serious public health challenge. Due to its asymptomatic onset and slow progression, patient persistence with topical glaucoma therapies remains low, significantly compromising treatment effectiveness. While some pharmaceutical companies have promoted disease awareness and improved eyedrop container usability, persistence may vary widely between products. However, no prior study in Japan has comprehensively examined persistence with antiglaucoma eyedrops by individual product or formulation characteristics. This study aimed to evaluate product-specific and formulation-specific persistence rates and identify patient factors associated with persistence, using large-scale Japanese medical insurance claims data. METHODS: We extracted records of patients who initiated single-product topical glaucoma therapy-without switching medications or using multiple eyedrop products concurrently-from Japanese medical claims database (January 2005 to June 2024). Year-by-year persistence from the first through fifth year was assessed for each patient. Persistence rates were analyzed according to drug product, drug class, dose/day, patient sex, and age. A gap of ≥ 90 days without prescription was defined as treatment discontinuation; sensitivity analyses using 60- and 120-day thresholds were also conducted. RESULTS: Records of 73,027 patients were analyzed. The overall 1-year persistence rate was 57.5%, declining to 23.8% at 5 years. Higher persistence was associated with female sex, older age (peaking in the 60s), and once-daily dosing. Among drug classes, prostanoid receptor agonists and their fixed-dose combinations with β-blockers exhibited higher persistence. Substantial inter-product variation was observed even within the same drug class. In a sub-analysis including patients who switched medications or used multiple eyedrops, notable improvements in persistence were found for carbonic anhydrase inhibitors and for regimens requiring twice- or thrice-daily administration. CONCLUSIONS: This study provides the first comprehensive analysis of product-specific persistence rates for topical glaucoma therapies in Japan. Product choice was shown to significantly influence persistence, alongside known factors such as patient sex, age, drug class, and dose/day. These findings have implications for drug development, product selection, and patient counseling aimed at improving the effectiveness and efficiency of long-term glaucoma management.