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
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 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
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 PEX1 Team Making It Happen
Dr. Catherine Argyriou
Children’s Hospital Los Angeles / USC
Dr. Nancy Braverman
McGill University Health Centre
Dr. Samy Omri
Research Institute of the McGill University Health Centre
Dr. Jean Bennett
University of Pennsylvania
Dr. Joseph Hacia
University of Southern California
Dr. Robert Koenekoop
Research Institute of the McGill University Health Centre
Dr. Alex Levin
University of Rochester
Dr. Matthew Benson
University of Alberta
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.
Restoration of Peroxisomal Function
- Suggests correction of the underlying cellular defect
- Preservation of retinal structure
- May help slow progression toward blindness
- Improved retinal response
- Suggests retinal cells are functioning more effectively
- Improved functional vision
- Supports continued advancement toward future clinical trials
- Based on preclinical in vitro and in vivo studies
Learn More About Project PEX1-Vision & the GFPD
Towards Retinal Gene Therapy
Portrait of a Perspective Vision Study
2022 Mission Part 3: Research and Advocacy
