Efficacy and side effects of latanoprost monotherapy compared to adding dorzolamide to timolol in patients with glaucoma and ocular hypertension - A three-month randomised study

PURPOSE. TO compare the efficacy and safety of latanoprost monotherapy or d orzolamide and timolol in glaucoma patients inadequately controlled on adre nergic beta-receptor antagonist therapy. METHODS. A total Of 164 patients with primary open-angle glaucoma, capsular glaucoma or ocular hypertension were included in a three-month, open-label , randomised multicentre study Patients with open-angle glaucoma were requi red to have IOP at least 22 mmHg and patients with ocular hypertension were required to have IOP at least 27 mmHg, on treatment with one or two ocular hypotensive drugs of which at least one had to be a beta-blocker. All pati ents were treated with timolol, 5 mg/ml twice daily, for a 2-4 week run-in period. They were then randomised to latanoprost, 50 mu g/ml once daily, or timolol 5 mg/ml plus dorzolamide, 20 mg/ml twice daily. The difference in mean diurnal IOP change from baseline to month 3 was compared in the two gr oups. RESULTS. When patients were switched to latanoprost, mean diurnal IOP was r educed by 5.2 mmHg (23%) compared to 4.0 mmHg (17%) in the group in which d orzolamide was added to timolol. The difference of 1.2 mmHg was statistical ly significant (p = 0.005). The majority of adverse events during both trea tments were judged as mild. CONCLUSIONS. The results suggest that a switch to latanoprost monotherapy i s an alternative to combined treatment with timolol and dorzolamide in pati ents inadequately controlled on a topical adrenergic beta-receptor antagoni st alone.