A Fixed Combination of Timolol and Pilocarpine

We evaluated the efficacy and safety of a fixed combination of 0.5% timolol and 2% pilocarpine (TP2) or 4% pilocarpine (TP4) in two double-masked, controlled clinical studies. In study 1, the 315 patients with inadequately controlled intraocular pressure while receiving 0.5% timolol (T0.5) were randomly assigned to receive TP2, TP4, or TO.5 b.i.d. for 4 weeks. In study 2, 179 patients with inadequately controlled intraocular pressure while receiving 4% pilocarpine (P4) were randomly assigned to receive TP2, TP4 (b.i.d.), or P4 (q.i.d.) for 3 weeks. The TP2 and TP4 were more effective than timolol twice daily or than pilocarpine four times daily. This difference between treatments was apparent in both the maximal and minimal anticipated daily mean intraocular pressure readings. This difference was also observed in the proportion of patients with controlled intraocular pressure (≤ 21 mm Hg). Within the detection limits of this study, no difference was observed between the two timolol/pilocarpine combinations (T0.5 timolol with either 2% or 4% pilocarpine). Other than pilocarpine-related ocular side effects and those previously reported with timolol, no untoward effects were observed. We conclude that for those patients requiring more than monotherapy with either timolol or pilocarpine, the combination of timolol and pilocarpine b.i.d. may offer additional intraocular pressure lowering with the benefits of twice-a-day instillation of a single product.