This is a two stage study.~Stage One will explore the dose response of three concentrations of DE-117 as monotherapy compared with 0.0015% tafluprost and placebo. The safety and efficacy of DE-117 as adjunctive therapy (with 0.0015% tafluprost) compared with 0.0015% tafluprost and placebo will also be evaluated. In addition, the additive effect of adjunctive therapy of each concentration will be compared with the corresponding monotherapy concentration.~Stage Two will assess the safety and efficacy of the optimal DE-117 concentration as monotherapy compared with 0.0015% tafluprost. The safety and efficacy of the optimal DE-117 concentration as adjunctive therapy (with 0.0015% tafluprost) compared with DE-117 monotherapy and 0.0015% tafluprost will also be evaluated.
The purpose of this study is to investigate the safety and efficacy of up to three concentrations of DE-117 ophthalmic solution (Low Dose, Medium Dose, and High Dose) as monotherapy and as adjunctive therapy (DE-117 ophthalmic solution with 0.0015% tafluprost) in subjects with primary open-angle glaucoma or ocular hypertension.