Project PEX1-Vision
Retinal Gene Therapy to Preserve Vision
Preserve a Child’s Ability to See the World
For children and adults with PEX1-related peroxisome biogenesis disorder, Zellweger spectrum disorder (PBD-ZSD), progressive retinal degeneration can lead to irreversible blindness, often beginning in infancy or early childhood.
Today, there are no approved therapies to stop or slow vision loss.
For the first time, a targeted retinal gene therapy may offer a path toward preserving meaningful vision.
- WE HAVE THE TEAM.
- WE HAVE THE SCIENCE.
- WE HAVE THE MOMEMTUM.
- NOW WE NEED THE FUNDING.
Why is there a focus on developing a gene therapy for vision?
A Proven
Scientific Model
Retinal gene therapy is one of the most clinically advanced and validated forms of gene therapy today with established surgical delivery approaches, measureable clinical outcomes, successful FDA-approved therapies in related retinal diseases, and strong regulatory precedent.
A Requested Treatment
Affected families cite vision loss as one of the most meaningful symptoms they hope future therapies address.
Vision Affects Everything
Losing sight affects a child’s ability to communicate, learn, make friends, explore, and fully understand the world around them.
A Model For Future Therapies
This clinical trial will expand scientific understanding of peroxisomes, leading to more discoveries and treatment advances.
Impact to Other Rare Diseases
Insights can be leveraged for other rare diseases. 1 in 10 people are diagnosed with a rare disorder. 95% of those disorders have no FDA- approved drug treatment.
What Progressive Vision Loss Looks Like
Vision loss affects far more than eyesight. For individuals living with PBD-ZSD, progressive retinal degeneration impacts communication, mobility, independence, learning, safety, and connection to the world around them. According to the GFPD’s Voice of the Patient Report, vision loss is among the most meaningful symptoms families hope future therapies can address.
Voices From the Community
The Science: Why This Is Possible Now
Retinal gene therapy is one of the most clinically advanced and validated forms of gene therapy today, with:
- established surgical delivery approaches
- measurable clinical outcomes
- successful FDA-approved therapies in related retinal diseases
- strong regulatory precedent
The eye is uniquely suited for gene therapy, making retinal disease one of the most promising areas for therapeutic development. Project PEX1-Vision is designed to deliver a functional copy of the PEX1 gene directly to retinal cells, with the goal of:
- restoring local peroxisomal function
- preserving retinal structure
- slowing progression of blindness
- preserving meaningful vision and independence
Project PEX1 Is Advancing
Funding the Next Critical Step
$4M+ UDS invested to date. $1.3M remains. More than $4 million has already been invested in Project PEX1-VISION. Preclinical proof-of-concept is complete, intellectual property is secured, and clinical-grade manufacturing is underway.
$1.3M is the final gap between completed science and allowing for a first-in-human clinical trial
The GFPD is seeking to raise
$1.3 Million
by the end of 2026 to reach the following critical milestones:
CRITICAL PRECLINICAL SAFETY TESTING
FDA AND INTERNATIONAL REGULATORY ENGAGEMENT
Road to Clinical Trials
The People Behind Project PEX1-Vision
Meet the Warriors
Behind every scientific milestone is a child, adult, and family navigating the realities of progressive vision loss and peroxisomal disease every day. Meet the individuals and families helping drive Project PEX1 forward.
Meet the Project PEX1: Vision Team Making It Happen
Dr. Catherine Argyriou, PhD
Children’s Hospital Los Angeles / University of Southern California
Dr. Argyriou designed and completed the preclinical efficacy studies behind Project PEX1-VISION, carrying that work from her doctoral training through her postdoctoral research. Today she coordinates every arm of the project, including manufacturing, toxicology studies, and intellectual property.
Dr. Nancy Braverman, MD
Research Institute of the McGill University Health Centre
Dr. Braverman is a world expert in peroxisomal disorders and has dedicated her career to understanding these conditions and developing therapies for them. She leads the natural history studies for Zellweger Spectrum Disorder (ZSD).
Dr. Samy Omri, PhD
Research Institute of the McGill University Health Centre
Dr. Omri is a technical expert in mouse retinal biology. He performed the assessments showing preservation of retinal structure following therapy.
Dr. Jean Bennett, MD, PhD
University of Pennsylvania
Dr. Bennett is a pioneer of retinal gene therapy: she developed the first taken from bench to approval, Luxturna, now internationally approved and available for clinical care. She has been a consultant and collaborator on Project PEX1-VISION from the very beginning, generating our therapeutic vectors and advising on study design. She also serves on the boards of several retinal gene therapy companies.
Dr. Joseph Hacia, PhD
University of Southern California
Dr. Hacia is an expert in peroxisomal biology and contributed to the vector development and cell engineering work for the project.
Dr. Robert Koenekoop, MD, PhD
Research Institute of the McGill University Health Centre
Dr. Koenekoop specializes in genetic retinal disease across the full path from molecular genetics and clinical ophthalmology to human trials and drug development, with a longstanding focus on childhood blindness. He has taken part in hundreds of ophthalmic clinical trials using advanced measures such as mobility courses, rod perimetry, and retinal cell imaging.
Dr. Alex Levin, MD
University of Rochester
Dr. Levin is an ophthalmologist specializing in inherited retinal diseases and has served as lead on multiple clinical trials. He has published clinical descriptions of patients with PEX-related disease, and he is the only physician worldwide to hold simultaneous US board certifications in pediatrics, ophthalmology, and child abuse pediatrics.
Dr. Matthew Benson, MD, PhD
University of Alberta
Dr. Benson is an academic ophthalmologist and retinal gene therapy surgeon whose work centers on genetic eye disease, including peroxisomal conditions. He is a co-investigator on two clinical trials.
Be a Hero – Why Preserving Vision Matters
Families participating in the Voice of the Patient Report consistently identified preservation of vision as one of the most meaningful potential treatment outcomes.
Protecting vision is a top priority for our community.
Families also emphasized the connection between vision and communication, especially for children who rely on assistive hearing and speech technologies that require visual engagement.
Early preclinical studies have shown encouraging signs that retinal gene therapy may help preserve meaningful vision in Project PEX1-Vision.
*In mice carrying the same PEX1 mutation most common in patients, a single injection of the therapy produced:*
- Vision was improved. Treated mice could track objects almost as well as healthy mice, and saw more than twice as sharply as untreated mice.
- Light-sensing cells survived. Untreated animals lost roughly three-quarters of the retinal cells needed for sight. In treated animals, those cells were preserved at near normal levels.
- Retinal damage was prevented. Treated retinas were almost entirely protected from the patches of tissue loss that lead to blindness.
- One injection, lasting benefit. Improvements appeared within two months and held through six months — the full length of the study.
*Omri et al., 2026 bioRxiv [Preprint]. 2026 May 14:2026.05.11.723906[manuscript under review]; building on Argyriou et al., Molecular Therapy: Methods & Clinical Development, 2021.*
I added a link to the preprint
Learn More About Project PEX1-Vision & the GFPD
Towards Retinal Gene Therapy for ZSD
Portrait of the Prospective Vision Study
2022 Mission Part 3: Research & Advocacy
Relevant Publications
