(Miami, FL) A research team led by Byron L. Lam, M.D., at the Bascom Palmer Eye Institute of the University of Miami Leonard M. Miller School of Medicine, part of UHealth – the University of Miami Health System, has performed gene therapy on a 47-year old man as part of a Phase 2 clinical trial to treat Choroideremia (CHM), a rare inherited cause of blindness. The Food and Drug Administration (FDA) approved clinical trial will ultimately treat six patients with CHM to help to determine the safety and efficacy of this novel treatment. A promising treatment for CHM had been elusive until the advent of gene therapy. The transfer of new genes into the dysfunctional cells has the potential to restore the health and function of these cells.
CHM is a progressive degenerative disorder of the retina and the choroid layers that line the inside of the back portion of the eye. CHM is caused by a genetic defect of the X-Chromosome that results in a faulty protein in the retina. Symptoms of CHM begin with a gradual loss of night and peripheral vision. Overtime, CHM leads to complete loss of central sight. CHM affects one in 50,000 people, and the vast majority of affected CHM persons are young men.
The approach used in this clinical trial was to use a large number of harmless viruses (AAV2-REP1) modified to carry copies of the normal gene into the eye to correct the genetic defect in CHM. The gene therapy was delivered to the space under the retina through an injection technique approved by the FDA for research purposes for this clinical trial. The injection provides controlled delivery of the gene therapy. The modified viruses infect retinal cells and carry copies of the normal gene into the cells where the normal gene continues to work to maintain the function and integrity of the cells. The goal of the treatment is to maintain or even improve visual function in CHM patients.
“We are extremely excited and optimistic about the success of this gene therapy trial,” says Lam. “We are continuing to treat more patients with CHM, and we hope the knowledge gained will help patients with other retinal diseases.” Lam added that this clinical trial was self-funded by Bascom Palmer and donors interested in retinal research.
Retinal surgeons, Janet L. Davis, M.D., and Ninel Gregori, M.D., performed the highly specialized surgery at Bascom Palmer that involved injecting a full dose of the vector under a very thin retina. The technique is challenging and was done successfully without damaging the retina.
The first clinical trial using the AAV2-REP1 approach to treat CHM was conducted at the University of Oxford under the direction of Dr. Robert MacLaren, a professor of ophthalmology. MacLaren and the Bascom Palmer team have collaborated on this project for the past year.
The gene therapy viral vector, known as AAV2-REP1, was provided by NightstaRx, a private biopharmaceutical company focused on the development of gene therapy for CHM. “Gene therapy has huge potential as a treatment for many patients who are suffering from genetic causes of blindness” says David Fellows, CEO of NightstaRx. “We have seen some very promising results from our CHM programme and have recently expanded our pipeline to include other inherited retinal dystrophy disorders as we continue to strive to restore or maintain sight in patients suffering from these devastating blinding diseases.”
Lam, the Robert Z. and Nancy J. Greene Chair in Ophthalmology, has a broad background in neuro-ophthalmology and hereditary retinal degenerations. He is Bascom Palmer’s medical director of neuro-ophthalmology and scientific co-director of the Adrienne Arsht Hope for Vision Retinal Degeneration Laboratory.
About Bascom Palmer Eye Institute
Bascom Palmer Eye Institute of the University of Miami Leonard M. Miller School of Medicine, part of UHealth – the University of Miami Health System, is ranked the nation’s best program in ophthalmology by U.S. News & World Report. As the largest ophthalmic care, research and educational facility in the southeastern United States, more than 250,000 patients with nearly every ophthalmic condition are treated each year and more than 12,000 surgeries are performed annually. Founded in 1962, Bascom Palmer has patient care facilities in Miami, Palm Beach Gardens, Naples, and Plantation, Florida. For additional information, please contact Marla Bercuson, executive director of business operations at (305) 326-6190, firstname.lastname@example.org or visit the website at www.bascompalmer.org
Nightstar is a private biopharmaceutical company focused on the development of therapies for retinal dystrophies. The Company’s lead programme is a retinal gene therapy for choroideremia, a rare inherited cause of blindness that affects around 1 in 50,000 people. Gene therapy has the potential to be an effective treatment for choroideremia and a range of other retinal dystrophies. The Company’s lead investor, Syncona LLP, an independent subsidiary of the Wellcome Trust, is an evergreen investment company, taking an active role in identifying, supporting and developing technologies with the potential to significantly impact the healthcare market of the future. www.nightstaRx.com
Choroideremia is an inherited X-linked recessive disease which inevitably causes blindness. It is caused by mutations to the CHM gene which encodes Rab-escort protein 1 and affects approximately 1 in 50,000 people. The first symptom of the condition is usually an impairment of night vision which often occurs in early childhood. This is followed by progressive narrowing of the field of vision, as well as a decrease in the ability to see details, culminating in blindness, most commonly in late adulthood. No effective treatment currently exists. For patients interested in participating in choroideremia trials please follow this link: https://www.nightstarx.com/patients/research/