Cost-effectiveness of Stepwise Eye Drop Strategies for Open-Angle Glaucoma: A Markov Model Analysis From the Japanese Healthcare Perspective

OBJECTIVES: Open-angle glaucoma is a common chronic condition that requires long-term eye drop treatments and thus economic burden. The study aims to evaluate the cost-effectiveness of stepwise eye drop treatments, focusing on latanoprost, timolol, and dorzolamide, from the Japanese healthcare payer's perspective. METHODS: The targeted eyedrops consisted of 3 individual active ingredients (latanoprost, timolol, and dorzolamide) and 2 fixed combinations (latanoprost/timolol and dorzolamide/timolol). In the absence of a predefined reference treatment strategy, all combination options were evaluated simultaneously. A Markov model simulated disease progression and treatment over a lifetime horizon. Transition probabilities were retrieved from some clinical trials. Costs were based on the 2024 Japanese Medical Fee Index and national drug price list. Health utilities were measured using European Quality of Life 5 Dimension 5 Level data from glaucoma patients. Deterministic and probabilistic sensitivity analyses addressed uncertainties, comparing brand-name and generic drug prices. Cost-effective threshold was set at 5 000 000 JPY/QALY (52 811 USD/QALY). RESULTS: Three cost-effective strategies were identified: timolol followed by dorzolamide/timolol, latanoprost followed by timolol, and timolol followed by latanoprost, with acceptability of 0.271, 0.256, and 0.193 at the threshold, respectively. Dorzolamide alone as a first-line therapy was not cost-effective. For generic drugs, starting with latanoprost followed by timolol, or vice versa, and using fixed combination strategies were cost-effective. CONCLUSIONS: For brand-name drugs, latanoprost followed by timolol or a timolol-first strategy with dorzolamide were the most cost-effective. For generics, starting with latanoprost or timolol, and following fixed combinations, were cost-effective. A timolol-first strategy followed by dorzolamide was cost-effective for brand-name drugs but not for generics.