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

The US Food and Drug Administration (FDA) has selected Abeona Therapeutics’ ABO-503 gene therapy for X-linked retinoschisis (XLRS) to participate in its Rare Disease Endpoint Advancement (RDEA) Pilot Program.

According to a press release from Abeona,¹ as part of the RDEA program, the company will have opportunities for enhanced communication and collaboration with the FDA, which includes “frequent advice and regular ad-hoc conversations to accelerate the development and validation of product-specific novel efficacy endpoints for Abeona’s XLRS program.”

The FDA describes the RDEA pilot program as a program to support novel endpoint efficacy development for drugs that treat rare diseases. Under the pilot program, between 2023 and 2027, the FDA will accept up to 1 RDEA proposal per quarter, with a maximum of 3 proposals per year. The FDA says that the program seeks to advance rare disease drug development programs by providing a “mechanism for sponsors to collaborate with the FDA throughout the efficacy endpoint development process.”²

An additional goal of the program, as noted by the FDA, is promoting “innovation and evolving science” by sharing learnings on novel endpoint development through FDA presentations, guidance documents, public workshops, and a public-facing website.²

Vish Seshadri, CEO of Abeona, commented on the program in a press release from the company, saying, “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 is composed of a functional human RS1 gene packaged in the novel AIM capsid AAV204 and has shown preclinical efficacy following delivery to the retina in a mouse model of XLRS, according to the company.

The company noted it plans on completing IND-enabling studies in the second half of 2026.

Recently, Beacon Therapeutics exercised its option agreement to license Abeona Therapeutics’ patented AAV204 capsid for use in potential gene therapies for a range of prevalent and rare retinal diseases that result in blindness.³

This worldwide, non-exclusive license is pursuant to the agreement between Abeona and Beacon that was announced in July 2024 to evaluate the therapeutic potential of AAV204.

References:

1. Abeona Therapeutics announces ABO-503 gene therapy for X-linked retinoschisis (XLRS) selected by FDA for Rare Disease Endpoint Advancement (RDEA) pilot program. Published October 13, 2025. Accessed October 13, 2025. https://investors.abeonatherapeutics.com/press-releases/detail/323/abeona-therapeutics-announces-abo-503-gene-therapy-for

2. Rare Disease Endpoint Advancement Pilot Program. The US Food and Drug Administration. Accessed October 13, 2025. https://www.fda.gov/drugs/development-resources/rare-disease-endpoint-advancement-pilot-program

3. Harp MD. Beacon Therapeutics exercises option to license Abeona Therapeutics’ AAV204 capsid. Published July 3, 2025. Accessed October 13, 2025. https://www.ophthalmologytimes.com/view/beacon-therapeutics-exercises-option-to-license-abeona-therapeutics-aav204-capsid