Abeona Therapeutics’ ABO-503 Selected for FDA’s Rare Disease Endpoint Advancement Pilot Program

The U.S. Food and Drug Administration (FDA) has selected Abeona Therapeutics’ ABO-503, an investigational gene therapy for X-linked retinoschisis (XLRS), to participate in the agency’s Rare Disease Endpoint Advancement (RDEA) Pilot Program. This selection marks a significant regulatory milestone for Abeona and offers the company expanded opportunities to collaborate with the FDA in developing novel efficacy endpoints for its XLRS program.

Enhanced Regulatory Support for ABO-503 Development

As outlined in Abeona’s press release, inclusion in the RDEA Pilot Program provides the company with enhanced communication channels with the FDA, including frequent advice and ad-hoc discussions. These engagements are designed to accelerate the development and validation of product-specific efficacy endpoints, a key factor in advancing therapies for rare diseases such as XLRS.

The RDEA Pilot Program, initiated by the FDA, aims to support sponsors in the development of innovative efficacy endpoints for rare disease treatments. Between 2023 and 2027, the FDA will accept up to one RDEA proposal per quarter, with a cap of three proposals annually. The program establishes a framework for sustained collaboration with the FDA throughout the endpoint development process.

Advancing Innovation in Rare Disease Drug Development

According to the FDA, the broader objectives of the RDEA initiative include fostering innovation and evolving science in clinical endpoint development. To facilitate this, the agency plans to share insights through public workshops, FDA presentations, guidance documents, and a dedicated public-facing website, allowing knowledge gained from pilot projects to inform future rare disease drug development efforts.

CEO Commentary

Commenting on the announcement, Vish Seshadri, CEO of Abeona Therapeutics, stated:

“We are honored that ABO-503 gene therapy for XLRS has been chosen for the FDA’s highly competitive RDEA pilot program. We believe our participation will meaningfully improve the success rate of our XLRS clinical development efforts and, more broadly, could help facilitate pipeline innovation by using novel efficacy endpoints in new therapy development across other inherited retinal diseases.”

ABO-503: A Novel Gene Therapy Candidate for XLRS

ABO-503 is designed to address XLRS, a rare inherited retinal disorder primarily affecting young males and characterized by splitting of the retinal layers, leading to progressive vision loss. The therapy consists of a functional human RS1 gene delivered via the AAV204 capsid, part of Abeona’s proprietary AIM vector platform. Preclinical studies in a mouse model of XLRS have demonstrated therapeutic efficacy following retinal delivery, according to company data.

Abeona has indicated that it plans to complete IND-enabling studies in the second half of 2026, moving the program closer to clinical evaluation.