Treatment with Nyxol® (phentolamine ophthalmic solution) was associated with a greater improvement in mesopic low contrast visual acuity (mLCVA) in patients with dim light vision disturbances compared with placebo, according to results from a phase 3 study.

Nyxol is a once-daily, preservative-free eye drop formulation of phentolamine mesylate, a nonselective alpha-1 and alpha-2 adrenergic antagonist designed to reduce pupil size. “The unique 24-hour duration of Nyxol’s effect in reducing pupil diameter makes this a convenient option for evening dosing for these patients, who find nighttime driving and other dim light activities challenging,” said Jay Pepose, MD, PhD, Chief Medical Advisor, Ocuphire Pharma.

The randomized, placebo-controlled, double-masked LYNX-1 study (ClinicalTrials.gov Identifier: NCT04638660) evaluated the efficacy and safety of Nyxol in 145 patients who experienced vision impairment under dim light conditions. Patients were randomly assigned to receive either Nyxol or placebo, self-administered in each eye once daily, at or near bedtime, for 14 days. The primary endpoint was the gain of 3 lines (or 15 letters) or more of distance vision improvement on a low contrast chart in dim light conditions.

Results showed that the study met the primary endpoint with 13% of patients in the Nyxol arm gaining at least 15 letters of mLCVA at day 8 compared with 3% in the placebo arm (P <.05). At day 15, 21% of Nyxol-treated patients gained at least 15 letters of mLCVA vs 3% in the placebo arm (P <.01).

Additionally, a greater proportion of patients treated with Nyxol gained at least 10 letters of mLCVA at day 8 (41% vs 22%; P <.05), and at day 15 (44% vs 23%; P <.05) compared with placebo, respectively (secondary endpoints). 

Adverse reactions with Nyxol were predominantly mild in severity and were consistent with those observed in previous trials.

“In distinction to some other classes of miotics, the mechanism of action of Nyxol obviates any increased risk of retinal tears or detachment in this cohort of patients, many of whom have longer axial lengths and are therefore at higher retinal detachment risk,” added Pepose.

Nyxol is being investigated across 12 US clinical trials. Additional data from the LYNX-1 study will be presented at upcoming medical conferences. 

Reference

Ocuphire announces positive topline results from LYNX-1 phase 3 trial evaluating Nyxol® eye drops for night vision disturbances. News release. Ocuphire Pharma, Inc. Accessed May 19, 2022. https://www.globenewswire.com/news-release/2022/05/19/2446751/0/en/Ocuphire-Announces-Positive-Topline-Results-from-LYNX-1-Phase-3-Trial-Evaluating-Nyxol-Eye-Drops-for-Night-Vision-Disturbances.html