24-Hour Control With a Latanoprost-Timolol Fixed Combination vs Timolol Alone

OBJECTIVE: To evaluate 24-hour intraocular pressure (IOP) control with an evening-dosed latanoprost-timolol maleate fixed combination vs timolol alone in patients with primary open-angle glaucoma. METHODS: After a medicine-free period, qualified patients were randomized to either placebo dosed in the morning with a latanoprost-timolol fixed combination dosed in the evening or timolol alone dosed twice daily for 8 weeks. Patients were then switched to the opposite treatment for 8 weeks. At baseline and at the end of each treatment period, patients underwent IOP measurements. RESULTS: Both treatments reduced the IOP from untreated baseline at each time point and for the 24-hour curve (P<.001). When treatments were compared, the latanoprost-timolol fixed combination decreased the IOP more than timolol alone at each time point and for the 24-hour curve (2.9 mm Hg), and provided a lower absolute IOP at each time point (P<.001) and for the range (fluctuation) in IOP (P = .003) and for the 24-hour curve. Several adverse effects were observed more often with the latanoprost-timolol fixed combination, including ocular stinging (P = .05), conjunctival hyperemia (P = .02), and ocular itching (P = .04). CONCLUSION: The evening-dosed latanoprost-timolol fixed combination may provide better IOP control than timolol alone over 24 hours and may demonstrate a narrower range of IOP fluctuation in patients with primary open-angle glaucoma.