ARVO 2019 took place at the Vancouver Convention Center from April 28 to May 2 and featured novel work, continued efforts, and updates on clinical trials. On the Friday before ARVO the Foundation Fighting Blindness and the Casey Eye Institute hosted a summit featuring gene therapy, stem cell therapies, and non-viral therapies.
Randy Wheelock had been organizing a special interest group on Sunday to discuss combination therapies before his passing. Ian MacDonald and Chris Moen took over the organization of that event, which ended up being an honest discussion of the biggest obstacles researchers see ahead of them. How do you measure a disease at very different stages? How do you design clinical endpoints for a disease that isn’t symmetrical like choroideremia? Can we combine multiple therapies to treat retinal diseases like is done with glaucoma or cancer? How long will a gene therapy product last in the retina, will it be around long enough to have a meaningful effect? The experts had some great opinions and ideas about how to deal with these issues.
Chris Moen spoke on a patient experience and advocacy panel, bringing his unique physician and patient perspective. He emphasized the need for ophthalmologists to see their patients as parents, spouses, children, and individuals, not just a diseased retina. The other speakers on this panel brought a variety of important perspectives to the table. I came away from ARVO this year recognizing the importance of partnering with other organizations and disease groups. It is nice to have a close-knit “family” that deals with the same disease, but when it comes to advocacy and having a greater impact we need to partner with others. The Million Dollar Bike Ride in Philly is a great example of this. Avril Daly from Retina International emphasized this point and I agree with her.
Tomas Aleman presented more follow up data from the Spark sponsored clinical trial in which 10 CHM patients were treated. He reported that 7 patients had stable visual acuity, 2 had a slight increase, and 1 patient lost some visual acuity compared to the uninjected eye. Rachel Huckfeldt presented 1.5 year follow up data on the expansion of that Spark trial into 5 more patients between the ages of 20 and 32. Unfortunately one surgery in this study caused the development of a macular hole in a patient which brought his vision from 20/20 to 20/80. My heart dropped when this result was presented, and it highlights the risk associated with subretinal injections in choroideremia patients.
Many posters and papers presented at ARVO focused on studying the progression of choroideremia and improving the techniques used in clinical trials. Jessica Morgan presented various studies using adaptive optics to image choroideremia photoreceptors at extremely high resolution to help quantify and understand disease progression. Other work focusing on the immunology of viral gene therapy quantified CHM patients’ immune response to a subretinal injection in clinical trials. Another poster tried to calculate the cost associated with choroidermia and how much a cure would be worth at different stages of the disease. This is important when trying to get insurance to cover future treatments.
Two areas of research that were markedly increased from last year were single cell sequencing and machine learning techniques. While neither of these is an immediate cure for choroideremia, they are both important fields that will contribute to our understanding of the disease.