Three randomized, multicenter, phase 2 studies demonstrated the efficacy and safety of omidenepag isopropyl as an alternative method to lower IOP, according to a study.
Omidenepag is a selective, non-prostaglandin, prostanoid E2 receptor 2 agonist that increases aqueous humor outflow through both the conventional and the uveoscleral pathways. In a previous phase 1 study, it was demonstrated to be effective and well tolerated.
Studies 1 and 2 were conducted in the United States, and study 3 was conducted in Japan. A total of 338 patients with open angle glaucoma or ocular hypertension were randomized to receive one daily drop of omidenepag isopropyl at one of seven different concentrations (from 0.0003% to 0.003%), latanoprost or placebo for 28 days (studies 1 and 3) or for 90 days (study 2).
Omidenepag isopropyl demonstrated stable IOP-lowering effect superior to placebo and comparable to latanoprost, with the best results at the 0.002% and 0.0025% concentrations. Increasing dose-dependent response was observed up to 0.002%, slightly decreasing at higher concentrations.
“These data suggest that there is a plateau in the dose-efficacy response at approximately 0.002%,” the authors wrote.
Omidenepag isopropyl 0.002% was therefore identified as the optimal dose for further phase 3 trials.
Side effects were mild or moderate. The most frequently reported adverse events were conjunctival hyperemia, at a dose-dependent frequency, followed by photophobia and eye pain.
The authors pointed out that current treatment options are associated with frequent and significant side effects and in many cases require adjunctive treatment.
“Therefore, there is a need for well-tolerated pharmacotherapies with a once-daily dosing regimen and novel mechanisms of action,” the authors said.
The inclusion of the two distinct populations increases the validity and generalizability of the results, they said. – by Michela Cimberle
Disclosure: Aihara reports receiving research support and honoraria/consultation fees from Santen and has participated in a company-sponsored speakers bureau. Please see the study for the other authors’ relevant financial disclosures.