Blog
This summer Canavan Foundation President Orren Alperstein traveled to San Francisco for a meeting at the offices of BridgeBio, one of the two biotech companies engaged in investigational gene therapy for Canavan Disease. Here are her observations and reflections.
Bridge Bio Informational Session
In July I had the opportunity to travel to San Francisco to the offices of BridgeBio, one of the two biotech companies engaged in investigational gene therapy for Canavan disease. There I joined an in-person information session about Canavan disease for approximately 300 employees. It was part of an ongoing program that introduces employees to the people living with and affected by the diseases BridgeBio researches.
Three Canavan Families: Three Different Experiences
Three Canavan families were represented. One was streamed in on a huge screen from another state with their teenaged child in a wheelchair. A second was present in person with their five-year-old Canavan child who had been dosed three years before with BridgeBio's investigational gene therapy, along with an older sibling and both parents. I was the third: a mother who lost a child to the disease at the age of seven close to thirty years ago.
The program was completely unscripted. We were invited to talk about our diagnostic journeys and to ask and answer questions of one another about what life was like – or had been - for our children and our families. There were many similarities. We had all noted early on that our children could not hold up their heads, sit unassisted, reach and grasp toys, talk or walk. We all noted how social our children were, how incredibly sweet. And two of us – I and the parents of the older child - noted the rapid decline of our children, the increasing stiffness, the difficulty swallowing, the challenges with sleeping and with seizures, the hospitalizations, and - as they got older - the pneumonias and the challenges of keeping their lungs clear and healthy.
However, there was a dramatic difference between the two Canavan children we could see: the five year old on stage and the teenager on the screen. At one point the five year old, impatient with all the talk, got down off their mother’s lap and walked over to their older sibling, and they started to play, poking one another, giggling and chatting. No one in the audience could fail to notice the contrast between the five year old cavorting on the stage and the teenager in the wheelchair on the screen who was receiving suction treatments as the audience watched. We were all deeply moved. It was a vivid, real-life representation of the possibilities of the gene therapy treatment being developed.
Two Studies: CANinform and CANaspire
BridgeBio has undertaken two studies. One, called CANinform, is a natural history study that looks at the progression of the disease in the absence of intervention. As of December, 2024, there were 67 participants in that study from 17 countries. The natural history data to date show little to no gains in motor function in individuals with Canavan disease between the age of 0-60 months who received no treatment. This highlights the difficulty in gaining and maintaining skills in this population.
The other, called CANaspire, has dosed eight participants with a low dose and six with a higher dose of an investigational treatment. The data from CANinform, the natural history study, forms the basis of comparison for CANaspire, the investigational gene therapy trial.
Encouraging Preliminary Results of CANaspire
According to the researchers, early clinical trial results show that children dosed with the experimental gene therapy candidate being investigated show promising signs of improved motor function over time compared to natural history data.
While “these early results are encouraging,” say BridgeBio researchers, “more participants will need to receive the investigational gene therapy and longer-duration data are needed in order to fully understand [its] safety and efficacy.” Furthermore, “results may not be typical for all participants.”
Nonetheless, “we continue to be encouraged by the results children are achieving in the CANaspire trial,” says Dr. Florian Eichler, M.D., director of the leukodystrophy service at Massachusetts General Hospital, Center for Rare Neurological Disease and principal investigator of CANaspire. “Compared to the natural course of Canavan disease, in which most children do not achieve developmental milestones beyond that of a 6 month old, the fact that some children are sitting independently, taking steps, or even walking post-dosing is truly remarkable.”
Looking forward to the future
There is no way to predict whether, or how long, the results of the gene therapy will persist. For now, however, I, for one, am amazed and incredibly grateful for the efforts and commitment the researchers and their team have brought to this endeavor - and thrilled with those giggles I recently heard in California.
