Lexington, Mass.– Aldeyra Therapeutics has received a Special Protocol Assessment (SPA) agreement letter from the U.S. Food and Drug Administration (FDA) for its investigational drug ADX-2191, a methotrexate formulation being developed for primary vitreoretinal lymphoma (PVRL), a rare and life-threatening eye cancer with no approved treatments.
The SPA agreement outlines a clinical trial design that the FDA considers adequate to support a future New Drug Application (NDA). Under the agreement, Aldeyra will conduct a randomized trial comparing cancer cell clearance over 30 days in up to 20 patients, who will receive either one or eight intraocular injections of ADX-2191. Prior studies suggest multiple injections are typically needed to eliminate cancer cells in PVRL.
Currently, PVRL is treated off-label with compounded methotrexate injections, which may vary in quality and volume. ADX-2191 is a proprietary, vitreous-compatible formulation designed specifically for use inside the eye, and Aldeyra hopes it will offer more consistent treatment with potentially reduced injection volume.
Aldeyra’s earlier effort to seek FDA approval based on existing literature was rejected in 2023, with regulators requiring additional controlled clinical data. The newly approved trial is expected to begin in late 2025, with results anticipated the following year.
