Long term IOP lowering efficacy of bimatoprost/timolol fixed combination: a 12 month prospective study.

Purpose: To evaluate the long-term IOP-lowering effect of an initially successful switch from prostaglandine-analog (PGA) monotherapy to bimatoprosttimolol fixed combination (BTFC) METHODS: Prospective, monocentric, open-labeled clinical trial. 30 patients with insufficient intraocular pressure (lOP) control under PGA monotherapy were screened. Following a one month run-in period of BTFC, patients who presented an effective IOP-lowering response were prospectively studied for an additional 11-month period. IOP, tolerability and safety (adverse reactions, slit lamp biomicroscopy) were further assessed at month 6 and month 12 after initiating BTFC.

Results: BTFC therapy significantly decreased IOP when compared to PGA monotherapy (PGA monotherapy: 17.3+/-3.8 mmHg; BTFC 1 month 13.2+/-3.3mmHg; p<0.05). This decrease from PGA-monotherapy IOP was sustained throughout the time-frame (6-month: 13.5+/-3.6mmHg; 12-month: 13.9+/-2.4mmHg; p<0.05 in pairwise comparison). There was no statistical difference in IOP between BTFC study visits (p>0.05). Of the 27 patients who had a satisfactory lOP-lowering response to BTFC after one month, 18 (66.7%) still had sufficient IOP control at the 12 month study visit. Therapy was discontinued at 1 month in 3 patients (2 due to intolerance to medication and 1 failing to achieve IOP control). No intolerability was reported beyond the 1 month of BTFC therapy.

Conclusion: In the majority of patients, the initial lOP lowering effect of replacing PGA monotherapy by BTFC seems to predict a long term response to the new treatment strategy.