Glaukos Corporation's New Drug Application (NDA) for Epioxa has been accepted by the U.S. Food and Drug Administration (FDA), marking a significant step toward a potential new treatment option for keratoconus. Epioxa, a next-generation corneal cross-linking therapy, is designed to halt the progression of this sight-threatening condition.
Epioxa: A Novel Approach to Keratoconus Treatment
Epioxa represents a potential advancement in keratoconus therapy. Thomas Burns, Glaukos chairman and chief executive officer, stated that Epioxa could be the first FDA-approved, non-invasive corneal cross-linking drug therapy that does not require removal of the corneal epithelium. This is a key differentiator from existing treatments, potentially reducing procedure times, improving patient comfort, and shortening recovery time.
Clinical Trial Data and Efficacy
The NDA submission includes data from two Phase 3 pivotal trials. Both trials successfully achieved their pre-specified primary efficacy endpoints and demonstrated favorable tolerability and safety profiles. One study showed a clinically meaningful and statistically significant improvement in maximum corneal curvature (Kmax) at 12 months compared to the sham/placebo-controlled arm. Specifically, 91.5% of patients in the treatment group completed the 12-month trial, compared to 90.9% in the control group.
Keratoconus: Disease Burden and Current Treatments
Keratoconus is characterized by progressive thinning and weakening of the cornea, often diagnosed in a patient’s teenage years. If left untreated, it can lead to vision loss and is a leading cause of corneal transplants in the United States. Approximately 90% of cases are bilateral, and up to 20% of patients may require a corneal transplant. While conventional treatments like eyeglasses or contact lenses manage symptoms, Glaukos' first-generation iLink therapy, Photrexa, is the only FDA-approved therapy shown to slow or halt disease progression.
Mechanism of Action and Key Features of Epioxa
Epioxa utilizes a novel drug formulation designed to penetrate the epithelial layer of the cornea, combined with a stronger UV-A irradiation protocol and supplemental oxygen to enhance cross-linking. This approach aims to strengthen corneal tissue and halt the progression of keratoconus while preserving the corneal epithelium.
Regulatory Timeline and Future Prospects
The FDA has set a Prescription Drug User Fee Act (PDUFA) goal date of October 20, 2025, for the completion of its review of the Epioxa NDA, reflecting a standard 10-month review period. If approved, Epioxa could become the first non-invasive corneal cross-linking therapy available to patients, offering a significant advancement in the treatment of keratoconus.
