Ocular hypotensive efficacy and safety of a combined formulation of betaxolol and pilocarpine.

PURPOSE: To evaluate the ocular hypotensive efficacy and safety of a fixed combination of betaxolol (0.25%) and pilocarpine (1.75%).

METHODS

Three multicenter, double-masked, parallel trials were completed in patients with primary open-angle glaucoma or ocular hypertension of 3 months' treatment duration. Studies 1 and 2 were three-arm comparisons of betaxolol, pilocarpine, and a fixed combination, each used 3 times daily. Study 3 was a two-arm study of the fixed combination with and without a surfactant, used twice daily. In all studies, there was a 1-month runin period with betaxolol 0.25% suspension given twice daily. There were 182 patients in Study 1, 186 patients in Study 2, and 166 patients in Study 3.

RESULTS

In all 3 studies, approximately 10% to 15% of patients treated with pilocarpine or the combination therapy were terminated from further participation because of typical pilocarpine side effects (eg, blurred vision, headache). In studies 1 and 2, there was a mean reduction in intraocular pressure from a betaxolol baseline of approximately 3 to 4 mmHg. Patients continuing on betaxolol alone or randomly assigned to pilocarpine alone experienced a mean reduction of 1 to 2 mm Hg. Overall, the combination was approximately 2 mmHg more effective than either betaxolol or pilocarpine alone. In Study 3, the two betaxolol combinations had equivalent efficacy.

CONCLUSION

In patients requiring more than one ocular hypotensive agent, the combination of betaxolol and pilocarpine in a single formulation appears to be an effective and relatively safe agent. The use of this combination agent promises the potential for enhanced patient convenience.