Efficacy and safety of timolol solution once daily vs timolol gel added to latanoprost.

Abstract

To compare the efficacy and safety of timolol hemihydrate 0.5% (Betimol, Ciba Vision Ophthalmics, Duluth, Georgia) vs timolol maleate gel-forming solution 0.5% (Timoptic-XE, Merck, Blue Bell, Pennsylvania), both given every morning added to latanoprost 0.005% given every evening. A multicenter, randomized, crossover comparison was performed in patients with primary open-angle glaucoma or ocular hypertension. After at least a 4-week run-in period with latanoprost 0.005% (Xalatan, Pharmacia & Upjohn, Kalamazoo, Michigan), both eyes from 30 patients (60 eyes) were randomly assigned to one of the two adjunctive therapies, timolol hemihydrate or timolol maleate gel for 6 weeks. At the end of the first period, the study medicine was discontinued for a 2-week washout period. Patients then received the opposite medication for the second 6-week period. This study had an 80% power to exclude a 1-mm Hg difference between groups. The baseline intraocular pressure after 1 month of latanoprost treatment only for all 30 subjects was 20.8 +/- 2.6 mm Hg. After 6 weeks of timolol hemihydrate, the 24-hour trough intraocular pressure was 17.5 +/- 3.4 mm Hg, and for timolol maleate gel, 17.9 +/- 3.5 mm Hg (P = .74). The peak level 2 hours after dosing for timolol hemihydate was 16.4 +/- 2.6 mm Hg, and for timolol maleate gel, 16.8 +/- 3.8 mm Hg (P = .84). No patient was discontinued from the study because of lack of efficacy. No differences were observed between treatments in visual acuity, anterior segment findings, or adverse events. Once-daily beta-blocker therapy is an effective ocular hypotensive adjunctive treatment 24 hours after dosing when added to latanoprost, for which timolol hemihydrate 0.5% solution and timolol maleate gel 0.5% appear equally effective and safe.