EyeCool Therapeutics announces results from pilot study of novel chronic ocular surface pain treatment

ETX-4143 is an investigational device which gently cools the surface of each eye to combat chronic ocular surface pain and discomfort. Image credit: ©dream@do – stock.adobe.com

Clinical-stage medical technology company EyeCool Therapeutics, Inc., announced positive results from a pilot study focused on its investigational device, ETX-4143. The device is intended for the treatment of chronic ocular surface pain (COSP).

EyeCool Therapeutics is based in Cambridge, Massachusetts. According to the company, the pilot-stage, randomised, double-masked study (NCT06479382) included 31 patients in Australia. Results were first presented at the American European Congress of Ophthalmic Surgery Winter Symposium in February, in Aspen, Colorado, and announced via press release in early May. The pilot study examined the safety and efficacy of ETX-4143 for treating COSP, often a persistent symptom of dry eye disease.

ETX-4143 is an investigational device designed to be used during an in-office outpatient procedure, the company said in its press release. The device gently cools the surface of each eye for 4 minutes. The cooling action targets the myelinated long ciliary nerves, which are associated with ocular pain. EyeCool Therapeutics reported that many patients experienced immediate relief and lasting effects which improved over the following weeks.

The study was not powered for statistical significance, but EyeCool Therapeutics reported that a statistically significant reduction in eye pain severity was observed. The device's performance was assessed using a recently-validated patient reported outcome instrument, specifically designed for COSP. EyeCool Therapeutics said full study results are on file and will be submitted for peer review in the near future.

The company noted that treated nerve fibres gradually regenerate myelin; after 2 to 3 months, patients may require subsequent retreatment as their symptoms return. Along with relief for COSP, patients who undergo treatment with ETX-4143 may also experience improvements in corneal sensitivity.

Rebecca Petris, co-founder and president of the non-profit Dry Eye Foundation, said that for most patients with dry eye disease, persistent pain is a major outcome which negatively impacts daily life activities. “Patients often describe their symptoms as burning, grittiness, light sensitivity, irritation, a dry feeling or with other words, but the missing link is that these are all pain symptoms,” she detailed. “For better patient outcomes, we need to see research and industry engaging specifically with chronic ocular surface pain and are pleased to see this sign of progress.”

Preeya K. Gupta, MD, a cornea and cataract surgeon at Triangle Eye Consultants in Raleigh, North Carolina said ETX-4143 would be a “very welcome addition” to the landscape of ocular surface therapies.

"Chronic ocular surface pain is a common complaint that brings many patients to see an eye doctor,” she said. “However, it is a condition that often goes undiagnosed or is misdiagnosed as dry-eye and therefore leaves patients entirely untreated.”

Alice Epitropoulos, MD, an ophthalmologist at Central Ohio Eye & Plastic Surgery, added, "There is an unmet need for new treatments that can safely and effectively manage COSP. I would be thrilled to finally have an option for these patients that could work seamlessly into my practice.”

Reference

1. EyeCool Therapeutics Announces Promising Results from Double-Masked Randomized Controlled Trial in Chronic Ocular Surface Pain (COSP). Press release. EyeCool Therapeutics. Published May 7, 2025. Accessed May 12, 2025. https://www.prnewswire.com/news-releases/eyecool-therapeutics-announces-promising-results-from-double-masked-randomized-controlled-trial-in-chronic-ocular-surface-pain-cosp-302447986.html