An observational study of bimatoprost 0.01% in patients on prior intraocular pressure-lowering therapy: the Canadian Lumigan^® RC Early Analysis Review (CLEAR) trial

Andrew C Crichton,¹ Donald R Nixon,² Susan Simonyi,³ Meetu Bhogal,³ Christopher S Sigouin,⁴ Marino J Discepola,⁵ Cindy ML Hutnik,⁶ Darryl C Baptiste,³ David B Yan⁷

On behalf of the CLEAR Study Group

¹Division of Ophthalmology, University of Calgary, Calgary, AB, Canada; ²Private practice, Barrie, ON, Canada; ³Medical Affairs, Allergan Inc., Markham, ON, Canada; ⁴CLINWest Research, Burlington, ON, Canada; ⁵Department of Ophthalmology, McGill University, Montreal, QC, Canada; ⁶Department of Ophthalmology and Pathology, Ivey Eye Institute, London, ON, Canada; ⁷Department of Ophthalmology, University of Toronto, Toronto, ON, Canada

Purpose: To evaluate the ocular hyperemia and intraocular pressure (IOP)-lowering efficacy of bimatoprost 0.01% in subjects with elevated IOP due to primary open-angle glaucoma (POAG) or ocular hypertension (OHT) in a real-world clinical setting.
Subjects and methods: This open-label, 12-week, observational study was conducted at 67 centers in Canada. Subjects with elevated IOP due to POAG or OHT instilled bimatoprost 0.01% as monotherapy once daily. Ocular hyperemia was graded by the investigator at baseline, week 6, and week 12 using a standardized photographic 5-point grading scale. Change in IOP from baseline was also evaluated at these time points. This analysis includes the subgroup of 268 subjects who had been previously treated with latanoprost 0.005%, bimatoprost 0.03%, travoprost 0.004%, and travoprost 0.004% with SofZia™ or nonselective beta-adrenergic receptor blockers prior to the study.
Results: After 12 weeks of treatment with 0.01% bimatoprost, ocular hyperemia was graded as none-to-mild hyperemia (grades 0, +0.5, or +1) for 94.1% of subjects and as moderate-to-severe hyperemia (grades +2 or +3) for 5.9%. No statistically significant shifts in ocular hyperemia ratings were observed at week 12 for any of the prior IOP-lowering therapies except bimatoprost 0.03%, in which 20.8% of subjects experienced an improvement. The mean percentage change from baseline IOP at week 12 following the switch to bimatoprost 0.01% monotherapy ranged from –2.3%±17.3% to –26.3%±12.4%. Furthermore, the decreased mean percentage change from baseline IOP was statistically significant across all prior IOP-lowering medications, except for bimatoprost 0.03% at the 6- and 12-week visits and travoprost 0.004% at the 6-week visit.
Conclusion: This observational study demonstrates that bimatoprost 0.01% was well tolerated among POAG and OHT subjects who switched from prior IOP-lowering medication. Furthermore, a switch in ocular hypertensive treatment to bimatoprost 0.01% was associated with an additional 10%–15% reduction in IOP.

Keywords: glaucoma, intraocular pressure, hyperemia, bimatoprost