Latanoprost: Experience of 2-year treatment in Scandinavia

Purpose: The aim of the study was to assess efficacy and side effects of la tano-prost during two years of treatment. Methods: The study was a randomized, parallel group, double-masked, multice nter comparison between latanoprost and timolol in patients with open angle glaucoma or ocular hypertension, followed by an open-label 18-month extens ion during which all patients were treated with latanoprost. Results: Latanoprost caused a marked and sustained reduction of the intraoc ular pressure (IOP), IOP was reduced from baseline levels 25.1+/-3.5 mm Hg (mean+/-SD) in 183 patients initially randomized to treatment with latanopr ost to 17.4+/-2.9 mm Hg (n=65) after 24 months of treatment. For patients i nitially randomized to treatment with timolol the corresponding figures wer e 24.3+/-2.3 mm Hg (n=72) and 17.4+/-2.6 (n=41) mm Hg after 18 months of tr eatment with latanoprost. Two patients were withdrawn because of uncontroll ed IOP and 11 patients required additional timolol treatment to maintain an adequate IOP control. Patients initially treated with timolol and switched to latanoprost had a further reduction of the IOP of 1.0 mm Hg after 6 mon ths of treatment with latanoprost (p<0.005). 46 patients were withdrawn fro m the study, mostly due to increased iris pigmentation or an iris color wit h known high risk of developing increased pigmentation, 22 patients develop ed increased pigmentation of the iris. The follow-up revealed no previously unknown ocular or systemic side effects. Conclusion: Once daily applications of latanoprost cause a marked and susta ined reduction of the IOP, The only clinically significant side effect note d was the increased pigmentation of the iris, most frequently seen in iride s with a mixture of brown and blue/gray or green colors, No systemic side e ffect was observed.