Ottawa researcher awarded $1.4M to lead international team developing gene therapy for retinal blindness

Ottawa - Leading vision researchers from Canada and the U.S. are embarking on a five-year, $1.4M collaborative project to develop a new gene therapy to prevent blindness due to retinal diseases. Canada’s largest private charity for vision research, the Foundation Fighting Blindness, is partnering with the Canadian Institutes of Health Research to fund the program. The research team includes six scientists led by Dr. Catherine Tsilfidis, Senior Scientist at the Ottawa Hospital Research Institute and Associate Professor in the Faculty of Medicine at the University of Ottawa.

“The goal of this project is to begin testing a new gene therapy in patients, who are losing their vision due to retinal disease, by the end of five years,” said Dr. Tsilfidis. “This is an ambitious goal, but we think it is achievable. Our results so far have been very encouraging and our team has the dedication and the experience to bring this into the clinic quickly.”

The retina is the inner lining of the eye that is responsible for sensing light. Millions of people in North America suffer from diseases that involve the retina, such as retinitis pigmentosa, glaucoma, retinal ischemia and age-related macular degeneration. Although the causes of these diseases are different, they all end in the same way: with retinal cells dying through a process called apoptosis, which leads to blindness.

Dr. Tsilfidis and her team have shown that a gene called XIAP can block this process and prevent retinal cell death. The gene can be delivered to the eye using a virus called Adeno-Associated Virus (AAV). This therapy has proven particularly promising in an experimental model of retinitis pigmentosa, a genetic condition and important cause of blindness in which a large portion of the outer layer of the retina is lost. XIAP gene therapy was able to protect the cells of this critical part of the eye from dying, resulting in significant preservation of vision.

“Currently there is no therapy to prevent blindness from most retinal diseases, which is devastating news to more than one million Canadians losing their sight,” said Sharon Colle, President and CEO of the Foundation Fighting Blindness. “But the outlook for these families is changing to a more hopeful one thanks to groundbreaking research like this new project to save sight.”

“I've always hoped to hold out long enough to walk my daughter down the aisle, instead of having her lead me down the aisle,” said David Kong of Ottawa who has retinitis pigmentosa. “Maybe no one else would tell the difference, but it wouldn’t feel the same. That’s what I hope for.”

The new funding will allow Dr. Tsilfidis and her colleagues to further refine XIAP gene therapy and prepare for patient trials. Dr. Tsilfidis’ former mentor, Dr. Robert Korneluk, will be a crucial member of the team. Dr. Korneluk discovered XIAP at CHEO Research Institute in 1996 and he has helped to develop a cancer therapy based on XIAP that is currently in clinical trials. Other members include Dr. William Hauswirth (University of Florida), Dr. David Zacks (Kellogg Eye Center and the University of Michigan) and Drs. Stuart Coupland and Brian Leonard (both from the University of Ottawa Eye Institute at The Ottawa Hospital). Together, the team has extensive expertise in retinal surgery, retinal imaging and gene therapy clinical trials.

“Researchers in Ottawa have been particularly successful in working together to move discoveries from the lab into the clinic and this is another great example,” said Dr. Duncan Stewart, CEO and Scientific Director, OHRI, Vice-President of Research, The Ottawa Hospital and Professor of Medicine, University of Ottawa. “I’m delighted that Dr. Tsilfidis’ research will also benefit from some of the new facilities we are building through the $32M Translation of Innovation into Medical Excellence grant we received just over a year ago.”