A Phase II Study on the Duration and Stability of the Intraocular Pressure-Lowering Effect and Tolerability of Tafluprost Compared With Latanoprost

Purpose: Tafluprost is a novel prostaglandin F-2 alpha-receptor agonist shown to lower intraocular pressure (IOP) in healthy humans and patients with elevated IOP. We investigated the efficacy, safety, and tolerability of tafluprost 0.0015% compared with latanoprost 0.005% in patients with primary open-angle glaucoma, exfoliation glaucoma, or ocular hypertension. Methods: This was a randomized, double-masked, active-controlled, parallel-group, multinational, and multicenter phase II study. Patients received either tafluprost 0.0015% (n = 19) or latanoprost 0.005% (n = 19), both once daily. The extent and duration of action of the IOP-lowering effects at Day 42 and Day 43 were the primary efficacy endpoints. Efficacy and safety parameters were analyzed throughout. Results: Maximum IOP reduction was achieved by Day 7 and was sustained until Day 42 in both groups (mean [standard deviation] change from baseline -9.7 [3.3] mm Hg for tafluprost and -8.8 [4.3] mm Hg for latanoprost). The overall treatment group difference was 0.17 mm Hg (95% confidence interval -1.27 to 1.61; P = 0.811). The IOP-lowering effect was maintained for >= 24 h after the last dose in both groups. Most adverse events were ocular and were similar in frequency and severity between groups. There were 3 severe adverse events, all ocular, and all in the tafluprost group (3/19 = 16%). Conclusions: Tafluprost and latanoprost have comparable effects on the extent, duration, and stability of IOP reduction, and are well tolerated in patients.