Efficacy and safety of switching to latanoprost 0.005%–timolol maleate 0.5% fixed-combination eyedrops from an unfixed combination for 36 months

PURPOSE: We prospectively investigated the intraocular pressure (IOP)-reducing effect, the visual field-maintenance effect, and the adverse reactions caused by administration of latanoprost/timolol maleate fixed-combination eyedrops for 3 years. SUBJECTS AND METHODS: The subjects were 162 patients (162 eyes) with glaucoma or ocular hypotension who were using latanoprost and timolol maleate eyedrops concomitantly. The latanoprost and timolol maleate eyedrop regimen was discontinued without any washout period and subsequently changed to a latanoprost–timolol maleate fixed-combination eyedrop regimen. IOP values before the change and at 6, 12, 18, 24, 30, and 36 months after the change were measured and compared. The Humphrey visual field test was conducted before the change and at 12, 24, and 36 months after the change, and mean-deviation values were compared. Adverse reactions were assessed at every checkup. RESULTS: The IOPs before the change and at 6–36 months after the change were 15.2±3.3 mmHg and 14.3–15.2 mmHg, respectively, and a significant decrease was observed at 36 months after the change (P<0.01). Mean-deviation values before the change and at 12–36 months after the change were −9.11±6.94 dB and −10.08 to −9.22 dB, respectively, and these values were not significantly different (P=0.2148). Within the 36-month period, the eyedrops were discontinued because of insufficient IOP decrease in 33 cases (20.4%) and adverse reactions in eleven cases (6.8%). CONCLUSION: IOP and the visual field were maintained for 3 years when a latanoprost and timolol maleate eyedrop regimen was changed to a latanoprost–timolol maleate fixed-combination eyedrop regimen. However, administration of the latanoprost–timolol maleate fixed-combination eyedrops was discontinued in approximately 27% of cases because of insufficient IOP decrease and adverse reactions.