Purpose: To investigate the intraocular pressure (IOP) lowering effect of bimatoprost (BIM) 0.03% and the potential additional effect of the BIM 0.03%/timolol 0.5% fixed combination (BTFC) in eyes with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma.
Methods: Following an appropriate washout period that varied with previous medication, participants with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma were treated with evening-dosed BIM for 5 weeks. They were then given evening-dosed BTFC for another 5 weeks. One randomly selected eye was evaluated. Goldmann applanation tonometry was performed by the same investigator at 8 a.m., 12 noon, 4 p.m., and 8 p.m. at baseline and at the end of each treatment period.
Results: Thirty-three participants completed the study. Three patients discontinued because of local adverse effects during the BIM treatment period. The mean diurnal IOP (mean ± SD) at baseline, on BIM, and on BTFC were 24.8 ± 5.4, 17.3 ± 3.5, and 14.9 ± 3.1 mmHg, respectively (repeated measures analysis of variance, P < 0.001 for all pairwise comparisons). The individual time-point IOP values showed similar significant reductions. The percentage of IOP reduction from baseline was 30.2% for BIM and 39.9% for the BTFC. The mean ± SD diurnal fluctuation at baseline was 6.8 ± 3.2 mmHg, which decreased to 4.0 ± 3.1 and 2.9 ± 1.4 mmHg on BIM and BTFC, respectively (P < 0.05 for both treatments versus baseline).
Conclusions: Both BIM 0.03% and the BTFC were effective in lowering IOP in eyes with ocular hypertension and open-angle glaucoma. However, the fixed combination provided an additional statistically significant reduction in IOP compared with BIM 0.03%.