Latanoprost or brimonidine as treatment for elevated intraocular pressure: multicenter trial in the United States

PURPOSE: To compare the efficacy and tolerability of latanoprost or brimonidine in patients with elevated intraocular pressure (IOP). MATERIALS AND METHODS: This prospective, randomized, masked-evaluator, parallel-group, multicenter study in the United States included patients with primary open angle glaucoma or ocular hypertension. Patients received latanoprost 0.005% once daily (8:00 AM; n = 152) or brimonidine tartrate 0.2% twice daily (8:00 AM and 8:00 PM; n = 151). Patients underwent evaluation at screening, baseline (randomization), and after 0.5, 3, and 6 months of treatment. IOP was measured at 8:00 AM, 10:00 AM, noon, and 4:00 PM at baseline and the months 3 and 6 visits, and at 8:00 AM only at week 2. The main outcome measure was the difference in diurnal IOP change from baseline to month 6 between treatment groups. Adverse events were recorded at each visit. RESULTS: Baseline mean diurnal IOP levels were similar between groups. At month 6, the adjusted mean (+/- SEM) diurnal IOP reduction was 5.7 +/- 0.3 mm Hg in the latanoprost group and 3.1 +/- 0.3 mm Hg in patients receiving brimonidine (P < 0.001). The mean difference in diurnal IOP reduction was 2.5 +/- 0.3 mm Hg (95% CI: 1.9, 3.2; P < 0.001). Five times more patients receiving brimonidine than latanoprost were withdrawn from the study due to adverse events. CONCLUSION: Latanoprost instilled once daily is more effective and better tolerated than brimonidine administered twice daily for the treatment of patients with glaucoma or ocular hypertension. During therapy, the range of daily fluctuation of IOP is less for latanoprost compared with brimonidine.