Opus’ phentolamine eye drops hit the LYNX-2 letter-gain target on mesopic low contrast distance visual acuity.
Opus Genetics (North Carolina, United States) has cracked the code on treating low-light vision problems that can plague post-LASIK patients.
The firm announced today that its LYNX-2 Phase III trial has successfully met its primary endpoint, with phentolamine ophthalmic solution 0.75% significantly improving mesopic low contrast distance visual acuity (mLCVA) in patients who underwent keratorefractive procedures.
The study’s primary endpoint measured the percentage of patients achieving at least a 15-letter (3-line) improvement on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart under mesopic low contrast conditions after 15 days of treatment.
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Results showed 17.3% of patients in the phentolamine arm achieved this threshold, compared to 9.2% in the placebo group (p<0.05). This represents a near-doubling of response rate for the active treatment.
“After just 15 days of treatment, 17% of patients with dysphotopsia following keratorefractive surgery achieved at least 15-letter gain in mesopic low contrast distance vision,” said Dr. Jay Pepose, chief medical advisor at Opus Genetics.
Phentolamine works as a non-selective alpha-1 and alpha-2 adrenergic antagonist, reducing pupil diameter through a sympatholytic mechanism. Unlike older parasympathomimetic agents, it avoids engaging the ciliary muscle, potentially reducing risks of retinal tears or detachment and increasing the potential safety profile of the drug.
The drug specifically blocks alpha-1 receptors on the radial iris dilator muscles without affecting accommodation, addressing the root cause of aberrations and light scatter that create glare, halos and starbursts in dim lighting conditions.
Trial design
The randomized, double-masked, placebo-controlled study enrolled 199 patients who had previously undergone keratorefractive surgery—including LASIK, PRK, SMILE and radial keratotomy—and reported decreased visual acuity under low-light, low-contrast conditions. Participants self-administered either phentolamine or placebo drops nightly in both eyes over a six-week treatment period.
The trial operated under a Special Protocol Assessment (SPA) agreement with the FDA and benefits from Fast Track Designation for treating significant, chronic night driving impairment in keratorefractive patients.
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Patient reported outcomes support topline results
But it wasn’t only the topline results that impressed.
Beyond the objective visual acuity measurements, the LYNX-2 Phase III trial captured patient-reported improvements using the validated Vision and Night Driving Questionnaire (VND-Q).
At Day 15, patients receiving phentolamine reported statistically significant improvements in two key areas: difficulty seeing the road due to oncoming headlights and difficulty seeing due to glare when driving at dawn or dusk (p<0.05).
“We also saw functional improvements in difficulty of seeing the road because of oncoming headlights; and difficulty seeing due to glare when driving at dawn or dusk, as reported by patients in the trial.”
Favorable safety profile
The treatment demonstrated a safety profile consistent with previous trials, with no new safety signals identified throughout the six-week study period. Importantly, researchers observed no evidence of tachyphylaxis—a diminishing response to the drug over time—during the treatment period.
Patients will continue under observation for long-term safety monitoring over 48 weeks, providing additional data on the drug’s extended use profile.
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Unmet needs for keratorefractive patients
Currently, no FDA-approved therapies exist for treating mesopic vision disturbances following keratorefractive surgery. The condition significantly impacts quality of life, particularly for night driving and functioning in dim environments.
“This data builds on earlier results from the LYNX-1 trial and provides evidence of efficacy for this condition, which currently has no FDA-approved therapies,” said Dr. George Magrath, CEO of Opus Genetics. “We believe this therapy could address a true unmet need and could offer meaningful benefits to keratorefractive patients experiencing glare, halos and reduced functional vision in low-light, low-contrast environments.”
The LYNX-2 results represent a milestone in developing the first treatment specifically targeting post-refractive surgery visual disturbances. With the rising popularity of keratorefractive surgery, ophthalmologists could soon have a new tool to combat one of the procedures’ most notorious downsides.
Editor’s Note: This content is intended exclusively for healthcare professionals. It is not intended for the general public. Products or therapies discussed may not be registered or approved in all jurisdictions, including Singapore.