Baby a pioneer of gene therapy for rare disease
OTTAWA, Ont. — Aidan Deschamps can crawl, climb stairs and, with the help of an ottoman or chair, stand. When his mother, Amanda Sully, or father, Adam Deschamps, holds his hands, he can even take some steps.
In other words, he’s cruising like most 10-month-old babies and hitting all the developmental milestones expected of him.
But things could have turned out much differently had Aidan been born a week earlier, or anywhere in Canada outside Ontario.
For, unbeknownst to him, the Ottawa baby is a pioneer in medicine, the first in Canada to be diagnosed with spinal muscular atrophy (SMA) using the province’s newborn screening test, and the first in the country, outside of clinical trials, to be subsequently treated for the rare and often fatal neuromuscular disease.
“There are no words for it,” his father said in a press conference held Wednesday to provide an update on Aidan’s health. “We are just so blessed that we live in the right place and that Aidan was born when he was. We’re still shocked to this day that we were that lucky.”
Born last January, Aidan was only 10 days old when his parents were contacted by the Newborn Screening Ontario unit at CHEO, telling them that their son had tested positive for SMA. The program takes small samples of blood from all newborns in the province, as well as parts of Nunavut, shortly after birth, and screens them for more than 25 diseases, including metabolic and endocrine diseases, Sickle Cell Disease, Cystic Fibrosis and Severe Combined Immune Deficiency, all of which can be more effectively treated when diagnosed early. Since 2006, the program has screened more than two million babies, identifying 2,500 with diseases.
“We were so fortunate to find out early,” said Sully, “because a delay in treatment would have meant longterm, irreversible consequences for him.”
Although SMA affects just one in 10,000 newborns, the disease, characterized by a weakening of the skeletal muscles, is nonetheless the most common cause of inherited death in childhood. In severe cases, symptoms appear before six months of age, and, if untreated, those with the disease rarely live past the age of two. Only through the recent development of therapies was it added — just six days before Aidan’s birth — to the list of conditions that are screened for in newborns.
According to Dr. Hugh McMillan, a pediatric neurologist at CHEO and clinical investigator at the hospital’s research institute, much of the research that has led to treatment for SMA has been done at CHEO.
“When I first started at CHEO as a neuromuscular expert in 2010, there were absolutely no treatments available,” he said, noting that children diagnosed then with SMA were given the necessary nutritional and respiratory supports, and assisted devices such as wheelchairs, to help them live “the best life possible.”
But research at CHEO, led by Dr. Alex MacKenzie, who discovered a gene – NAIP – which may contribute to the severity of the disease, helped develop treatment therapies.
One of them, which Aidan was first given when he was about three weeks old, is known as Spinraza. Approved in Canada, it corrects how the faulty gene produces certain proteins, but requires repeated treatments via spinal taps throughout the person’s life.
A second treatment, a gene-replacement therapy called Zolgensma, only needs to be administered once, but is not yet approved in Canada and is prohibitively expensive: more than $2 million in the U.S.
“Our immediate families volunteered to remortgage their houses and help fundraise,” recalls Adam, while the couple planned to sell their house and move in with family.
Fortunately, they didn’t have to. Through the manufacturer’s managed access program, the drug was made available on a compassionate basis to Aidan, who received it two weeks after his first treatment.
There’s no definitive test to say how well Aidan’s treatment has worked, but, according to Dr. McMillan, many of the newborns who initially received Zolgensma are now five and six years old, “and they continue to show robust strong effects to the gene-replacement therapy, and they’ve had no symptoms of clinical deterioration and no signs of any wearing- off effects.”
For Sully and Deschamps, the proof so far is in seeing their son approach his first birthday with no signs of the disease. “We see him as a physically active child who climbs two sets of stairs with ease and cruises around the house like he owns it. He dances to music, he throws and chases balls, and he chases our cats. We are so thankful.”