Aim: To determine utilisation patterns and calculate treatment failure and dis continuation rates in patients with open angle glaucoma tr eated in the United Kingdom with any of six groups of intraocular pressure (IOP) lowering agents. Methods: The UK General Practice Research Database was used to identify newly diagnosed (after 1 January 1997) open angle glaucoma patients wh o were naive to therapy with any of six index drug groups: carbonic anhydrase in hibitors, latanoprost, miotics, sympathomimetics, timolol, and other (non timol ol) βblockers. Analyses included drug treatment data for 1 year following diagn osis. Outcomes were (1) time to therapy failure, defined as either change in ind ex drug (replacement or addition of therapy) or patient referral for surgery, an d (2) time to therapy discontinuation, defined as either therapy failure or no r efill of the index drug in a period twice that covered by the first prescription fill. Cox proportional hazard regression and Ka plan Meier and life table met hods were used to compare groups. Results: Among the 2001 eligible patients, a βblocker other than timolol was the most widely prescribed (42%), followed by timolol (32%), carbonic anhydrase inhibitors (10%), and latanoprost (7%). Com pared to latanoprost, those treated with any alternative agent were significantl y more likely to fail (P ≤0.005 for each comparison) and to discontinue (P ≤0. 05 for each comparison) therapy. Failure rates ranged from 13%(latanoprost) to 45%(sympathomimetics), and discontinuation rates ranged from 30%(latanoprost) to 63%(miotics). Conclusion: Latanoprost treated patients demonstrated lower ra tes of therapy failure and therapy discontinuation compared with patients treate d with other widely used IOP lowering medications, including βblockers. Aim: To determine utilization patterns and calculate treatment failure and discontinuation rates in patients with open angle glaucoma tr eated in the United Kingdom with any of six groups of intraocular pressure (IOP) lowering agents. Methods: The UK General Practice Research Database was used to identify newly diagnosed (after 1 January 1997) open angle glaucoma patients wh o were naive to therapy with any of six index drug groups: carbonic anhydrase in hibitors, latanoprost, miotics, sympathomimetics, timolol, and other (non timol ol) beta blockers. Analyzes included drug treatment data for 1 year following diagnosis. Outcomes were (1) time to therapy failure, defined as either change in ind ex drug (replacement or addition of therapy) or patient referral for surgery, an d (2) time to therapy discontinuation, defined as either therapy failure or no r efill of the index drug in a period twice that covered by the first prescription fill. Cox proportional hazard regression and Ka plan Me Results: Among the 2001 eligible patients, a β blocker other than timolol was the most widely prescribed (42%), followed by timolol (32%), carbonic anhydrase inhibitors (10%) , and latanoprost (7%). Com pared to latanoprost, those treated with any alternative agent were significantl y more likely to fail (P ≤ 0.005 for each comparison) and to discontinue (P ≤ 0.05 for each comparison) therapy. Failure Rates ranged from 13% (latanoprost) to 45% (sympathomimetics), and discontinuation rates ranged from 30% (latanoprost) to 63% (miotics). Conclusion: Latanoprost treated patients displayed lower ra tes of therapy failure and therapy discontinuation compared with patients treate d with other widely used IOP lowering medications, including beta blockers.