24-Hour IOP control with once-daily bimatoprost, timolol gel-forming solution, or latanoprost: a 1-month, randomized, comparative clinical trial.

PURPOSE

To compare the efficacy and safety of once-daily (QD) bimatoprost, latanoprost, and timolol gel-forming solution in providing 24-hour intraocular pressure (IOP) control.

DESIGN

This was a randomized, multicenter, investigator-masked, prospective, parallel-group, clinical trial.

PARTICIPANTS

Patients with open-angle glaucoma or ocular hypertension.

INTERVENTION

After washout of any previous ocular hypotensive medications, patients were randomly assigned to treatment with bimatoprost 0.03% ophthalmic solution QD (n=38) or latanoprost 0.005% ophthalmic solution QD (n=38) between 7 and 9 pm, or timolol maleate 0.5% gel-forming ophthalmic solution QD (n=39) between 7 and 9 am for 1 month.

MAIN OUTCOME MEASURES

The primary outcome measure, circadian IOP, was measured at eight time points over the course of 24 hours beginning at 8 am on day 28 and with the last measurement at 8 am on day 29. IOP was also measured at 8 am and 10 am at baseline and at 8 am on day 14. Safety measures included adverse events, biomicroscopy, visual acuity, heart rate, and blood pressure.

RESULTS

At 10 am (peak drug effect) on day 28, the mean IOP reduction from baseline was significantly greater with bimatoprost (9.3 mm Hg, 40.3%) than with timolol gel (7.1 mm Hg, 31.1%; P=.024, Wilcoxon rank sum test) or latanoprost (7.4 mm Hg, 33.3%). In the overall analysis of IOP measured over the course of 24 hours, mean IOP was significantly lower with bimatoprost or latanoprost than with timolol gel (P<.001; analysis of repeated measures). The analysis of repeated measures also showed a significant difference between bimatoprost and latanoprost (P=.003). In the area-under-the-curve analysis, bimatoprost and latanoprost were superior to timolol gel (P< or =.018) but comparable to each other (P> or =.223). All treatment regimens were well tolerated, with few discontinuations due to adverse events. There were no significant effects on systemic safety parameters.

CONCLUSION

Once-daily bimatoprost or latanoprost provided significantly better 24-hour IOP control than timolol gel in patients with glaucoma or ocular hypertension. Some measurements suggested a trend for greater efficacy of bimatoprost over latanoprost. All three treatments were well tolerated.