Timolol-pilocarpine fixed-ratio combinations in the treatment of chronic open angle glaucoma. A controlled multicenter study of 48 weeks. Scandinavian Timpilo Study Group

T. J. Puustjarvi and L. P. Repo
Department of Ophthalmology, Kuopio University Hospital, Finland.

The effect of the fixed combination of 0.5% timolol maleate with 2% pilocarpine hydrochloride given twice a day and 0.5% timolol with 4% pilocarpine given twice a day was tested in a long-term, multicenter study. A total of 360 patients with open angle glaucoma were included; they were defined as those who had intraocular pressure greater than 21 mm Hg while receiving single, topical antiglaucoma therapy. Primarily, the purpose of the study was to investigate the efficacy of 0.5% timolol-2% pilocarpine, and second, to see to what extent an increase in concentration to 0.5% timolol-4% pilocarpine would further lower intraocular pressure in those patients with an intraocular pressure of greater than 21 mm Hg while taking 0.5% timolol-2% pilocarpine. The cohort of 228 patients went through the examinations for a total of 48 weeks. A mean decrease in intraocular pressure from 24.7 +/- 2.8 to 21.0 +/- 3.8 mm Hg was observed. During the trial, approximately 33% of the patients required an increase in concentration to 0.5% timolol-4% pilocarpine after the week 8 examination. At week 12, in those using 0.5% timolol-4% pilocarpine, an additional 2.2 mm Hg lowering of intraocular pressure was observed. Side effects were minor and temporary and did not necessitate withdrawal from the study.