Effectiveness and Tolerance of beta-Blocker/Pilocarpine Combination Eye Drops in Primary Open-Angle Glaucoma and High Intraocular Pressure.

OBJECTIVE AND METHOD: A randomized, double-blind, parallel-group study compared the effectiveness and tolerability of three treatments for glaucoma: 2% carteolol/2% pilocarpine fixed-ratio combination (CBS 341A) twice a day, versus a 0.5% timolol/2% pilocarpine fixed combination twice a day versus 2% carteolol twice a day and 2% pilocarpine three times a day. The treatment period lasted 2 months. At the end of the comparative study, CBS 341A was evaluated in an open-label study during 1 year in the same patients. Seventy-two patients with primary open-angle glaucoma or high intraocular pressure were included in the study. Their intraocular pressure was >21 mm Hg while receiving beta-blocker eyedrops alone. After 15 days and 2 months of treatment with one of the three study treatments, intraocular pressure was measured at 12 noon and 7 p.m. RESULTS AND CONCLUSION: The three treatments reduced intraocular pressure similarly but there was a trend toward better intraocular pressure control with administration of the individual drugs as measured at 7 p.m. Mean reductions in intraocular pressure at 7 p.m. on day 60 were the following: 6.04 mm Hg in the CBS 341A group, 5.67 mm Hg in the timolol/pilocarpine group, and 7.90 mm Hg in the group with the individual drugs. Test medications were well tolerated apart from the usual and well-known effects of pilocarpine. At the end of the double-blind period, 70 patients received CBS 341A for 1 year. Intraocular pressure was measured at noon every 4 months. Fifty-three patients had controlled intraocular pressure with CBS 341A alone. Among the other 17 patients, 2 dropped out, 5 had to change their treatment because of disease progression, 6 underwent argon laser trabeculoplasty, 3 required carbonic anhydrase inhibitor, and 1 had trabeculectomy. There were no withdrawals for intolerance.