The promising initial results of an enzyme therapy replacement safety trial involving a 48-year-old Calgary man with Fabry disease has researchers cautiously optimistic that a new era of genetic disease treatment has dawned.
Dr. Aneal Khan, an associate professor of medical genetics and pediatrics at the University of Calgary and Alberta Children’s Hospital, says, prior to this trial, treating genetic disease had been an effort to soften symptoms through medication as opposed to fixing the problem.
“We removed stem cells from a patient here in Calgary with a team of investigators,” explained Khan of the process. “We sent the cells to Toronto where Dr. Jeffrey Medin and his team put a copy of the working gene by using a virus, called the Lentivirus, into the stem cells and then the virus is gone. There’s no virus left anymore and now the cells have a new working copy of the gene.”
“We injected the cells back into the patient and the patient’s immune system has recovered (and) the patient is back on their regular enzyme replacement therapy as well.”
The patient, Calgarian Darren Bidulka, says he was fortunate to have his Fabry disease diagnosed with little delay as the condition, which can result in the deterioration of interior organs due to the buildup of a particular protein (Gb3), is often misdiagnosed.
“It’s a miraculous difference in my quality of life that I was diagnosed when I was and that I was able to get access to the enzyme replacement therapy,” said Bidulka. “I basically have normal kidney function as opposed to no kidney function.”
Patients with Fabry disease are incapable of producing the enzyme that breaks down Gb3.
According to Khan, Bidulka was the first patient with Fabry disease in the world to undergo gene therapy treatment for the condition and possibly the first patient with inborn errors of metabolism to be treated in Canada using these methods. The introduced cells with the replicated genes have been successfully recreated by Bidulka’s stem cells.
“We did some bloodwork to see if the copy of the gene we inserted made it to the patient and the bloodwork shows that it is in the blood of the patient.”
Khan says Bidulka will continue to undergo testing over the next five years to ensure there are no complications as a result of the treatment.
“We’re working towards a cure (but) I don’t think we’re there yet,” said Khan. “What this does is enhance what we are doing. We’re looking to see how much better we can get at treating the disease.”
“We’re hoping we’re entering an era where, (with) rare genetic diseases, there may be some more hope to correct them using these technologies.”
With files from CTV Calgary's Brad MacLeod
