Zolgensma Approved to Treat Young SMA Patients in Canada

Health Canada has approved Novartis‘ gene therapy Zolgensma (onasemnogene abeparvovec) to treat pediatric spinal muscular atrophy (SMA) patients who have three or fewer copies of the SMN2 gene, or with infantile-onset disease.

“Today’s announcement about the Canadian approval of Zolgensma is a significant milestone in our journey to reimagine medicine by changing the treatment paradigm for children with SMA,” Andrea Marazzi, country head of Novartis Pharmaceuticals Canada, said in a press release.

SMA is caused by a lack of the SMN protein, needed for cells in the nervous system to survive and function properly. Its loss is due to mutations in the gene SMN1, which codes for SMN. Another gene — called SMN2 — can also produce some SMN protein, though not enough to compensate for the mutated SMN1. Different people have different numbers of copies of the SMN2 gene. In general, more SMN2 copies equate to less severe disease.

Zolgensma is a one-time therapy that works by using a viral vector to deliver a non-mutated version of the SMN1 gene to a patient’s cells. This allows the cells to produce a working SMN protein at levels sufficient to stop disease progression.

Health Canada’s decision covers children with SMA who have bi-allelic mutations in SMN1 — meaning both copies of the gene (one from each biological parent) are mutated — and who have three or fewer copies of SMN2, or who have infantile-onset SMA, also known as type 1 disease. The gene therapy will be given to patients through an intravenous (IV) infusion.

“The approval of Zolgensma in Canada offers children an opportunity to maximize their developmental potential from this one-time therapy,” said Hugh McMillan, MD, a pediatric neurologist at Children’s Hospital of Eastern Ontario in Ottawa.

Zolgensma’s safety and efficacy were demonstrated in several clinical trials. The gene therapy was approved in the U.S. in 2019, and it received conditional approval from the European Commission earlier this year.

“Zolgensma offers, in a single dose, the possibility of halting the progression of this degenerative condition that can rob children of regular developmental milestones,” said Nicolas Chrestian, chief of pediatric neurology at Centre Hospitalier Mère Enfant Soleil, Université Laval in Québec City.

“When I first started diagnosing SMA, I couldn’t have imagined that we would see such scientific advancements,” Chrestian added.

Currently, 13 Zolgensma treatment sites have been identified in leading Canadian healthcare institutions with SMA expertise. The sites are located in Vancouver, BC; Edmonton, AB; Calgary, AB; Saskatoon, SK; Winnipeg, MB; London, ON; Hamilton, ON; Toronto, ON; Ottawa, ON; Montreal, QC; Quebec City, QC; and, Halifax, NS.

“The SMA community is thrilled to have another treatment option to offer hope to families grappling with an SMA diagnosis,” said Susi Vander Wyk, executive director of CureSMA Canada. “The approval of Zolgensma couldn’t come soon enough. We will continue to advocate until everyone who needs access to treatment can benefit from innovations like this.”