RegeneRx, HLB Therapeutics sign letter of intent for Phase 3 clinical trials in neurotrophic keratitis

RegeneRX Biopharmaceuticals and its United States joint venture partner and licensee, HLB Therapeutics, signed a letter of intent this week with a global ophthalmology contract research organization to conduct a pair of Phase 3 clinical trials simultaneously beginning in the fall in the US and Europe for patients with neurotrophic keratitis.

The FDA requires two successful Phase 3 trials in most circumstances prior to submitting a new drug or biologics application (NDA/BLA). The purpose of conducting simultaneous trials is to reduce the time required to complete Phase 3.

"ReGenTree will seek to confirm the efficacy observed in SEER-1 despite the very small number of subjects in that trial. Based on the results of the SEER-1 study, HLB Therapeutics decided to conduct two clinical trials for neurotrophic keratitis at the same time because it is expected that RGN-259 would have a high possibility of success in this disease. Unlike dry eye disease, clinical studies for neurotrophic keratitis require a very simple and clear single primary endpoint, such as complete healing," according to HLB Therapeutics.

Currently, Oxervate, developed by Dompé, is the only available treatment for neurotrophic keratitis in the United States. The contract research organization, which signed the letter of intent with ReGenTree, a US joint venture between RegeneRx and HLB Therapeutics, participated in the clinical trial of Oxervate and has clinical experience and expertise in neurotrophic keratitis clinical trials. Neurotrophic Keratitis is a relatively large market for rare diseases as about 20,000 patients contract this disease annually in the United States.

In October, ReGenTree plans to apply to the FDA for a Special Protocol Assessment (SPA) for an additional dry eye trial (ARISE-4). The SPA program allows FDA specialists to provide input and collaborate with a sponsor (ReGenTree) in setting up clinical protocols and statistical analysis plans, which is binding. By participating together at this stage of the protocol development, the sponsor and FDA have a clear understanding of the requisite trial protocol.

"We are pleased HLB Therapeutics is continuing to move forward with both neurotrophic keratitis and dry eye disease clinical trials with RGN-259 as previously discussed,” J.J. Finkelstein, RegeneRx's president and chief executive, said in a news release. “Accelerating neurotrophic keratitis clinical development by simultaneously conducting two trials will speed up the process while also working with the FDA under an SPA to refine our approach to DED.”

RGN-259 is a sterile, preservative-free, eye drop developed to reduce damage and improve healing for various ophthalmic indications including dry eye syndrome and neurotrophic keratopathy. To date, more than 1700 subjects have received RGN-259 indicating various degrees of efficacy in both dry eye disease and neurotrophic keratitis.

RGN-259 has shown to be quick-acting, well-tolerated and does not have the documented side effects of other approved pharmaceutical products for these indications. Thymosin beta 4, the active pharmaceutical ingredient of RGN-259, that has demonstrated various mechanisms of action, including promotion of cell migration, cytoprotection, wound healing, and anti-inflammatory properties.