Ocuphire Pharma, Inc. announced the enrollment of the first subject in the LYNX-2 Phase 3 registration study evaluating Phentolamine Ophthalmic Solution 0.75% (PS) for the treatment of decreased visual acuity under low (mesopic) light conditions following keratorefractive surgery. The LYNX-2 trial is being conducted under conditions of a Special Protocol Assessment (SPA) with the U.S. Food and Drug Administration (FDA). As previously announced, Ocuphire received written agreement from the FDA that the clinical trial protocol and planned statistical analysis of the LYNX-2 phase 3 trial would adequately address objectives supporting regulatory submission and a potential future marketing application in this indication.

Vision disturbances under low light conditions are characterized by peripheral corneal imperfections (aberrations) that result in unfocused light when the pupil dilates under low light conditions. Patients experience decreased low contrast visual acuity as well as glare, halos and starbursts. Patients undergoing keratorefractive surgery (including LASIK, PRK, SMILE, and RK) have been identified as one of the major sub-populations affected, the others being those who have night myopia (naturally occurring), non-central cortical cataracts, keratoconus or post-multifocal or extended depth of focus intraocular lens (IOL) implantation.

There are currently no FDA-approved treatments for visual disturbances under low light conditions. With a mechanism of action that moderately reduces pupil size without the increased risks of retinal tears or detachment associated with parasympathomimetic miotics that engage the ciliary muscle, PS eye drops have the potential to be a treatment option that could improve patients? ability to see and function in low light.

The previous LYNX-1 Phase 3 study evaluating PS successfully met its primary endpoint, with 13% of subjects gaining 15 or more ETDRS letters of mesopic low contrast distance visual acuity at Day 8 vs. 3% on placebo (p<0.05). PS is manufactured as a preservative-free eye drop, which potentially allows for continued use while avoiding the common side effects of preservatives, such as ocular surface damage, eye irritation and tear film instability.