Newborn Screening for SMA Now Launched in Canadian Province
Babies born in the Canadian province of Saskatchewan will now be tested for spinal muscular atrophy (SMA) as part of routine newborn screening.
SMA is one of four medical conditions that have been added to the screening program administered to newly born infants by the Saskatchewan Health Authority.
“Our government is pleased to announce expanded screening for certain childhood conditions that have viable medical treatments available,” Paul Merriman, Saskatchewan’s Health Minister, said in a press release.
Two of the other conditions are hemoglobinopathies, genetic disorders such as sickle cell disease that affect the oxygen-carrying blood protein hemoglobin, and SCID or severe combined immunodeficiency. SCID is a genetic disorder in which the immune system does not function correctly. The fourth disorder for which infants will be screened is congenital cytomegalovirus, an infection that babies can be born with and that can lead to hearing loss.
As with SMA, care for these conditions has improved markedly in recent years.
Implementation of newborn screening for all four conditions has already started, and is expected to be completed by the end of the year.
SMA is caused by mutations in the gene that provides instructions for making a protein called SMN. Without a functional version of this protein, motor neurons — the nerve cells that control movement — die, ultimately giving rise to most of the disease’s symptoms.
Over the past few years, three treatments for SMA — Spinraza (nusinersen), Zolgensma (onasemnogene abeparvovec-xioi), and most recently Evrysdi (risdiplam) — have been approved in Canada, as well as in many other countries around the world. While the exact mechanisms differ therapy-to-therapy, all of these treatments broadly work by increasing levels of functional SMN protein in the body, helping to prevent the degeneration of motor neurons.
Spinraza currently is available as an eligible benefit in Saskatchewan for patients with SMA who meet certain criteria. Now, the province also has reached an agreement for Zolgensma and Evrysdi to be covered. According to the press release, coverage will be announced in the coming weeks.
In clinical trials, these treatments have been proven to be able to prevent the progression of SMA. However, existing treatments generally cannot undo damage that has already been done.
Consequently, as treatments have become more widely available, there has been a push in Canada and elsewhere to implement systems to allow those with SMA to be diagnosed as early as possible and avoid disease progression.
Newborn screening is a common strategy for early diagnosis that, as the name suggests, involves testing babies for SMA and other diseases almost immediately after birth, usually via an analysis of blood collected by pricking the baby’s heel.
“With province-wide testing, we can detect more of these medical conditions than ever before,” Merriman said. “A modernized universal newborn screening program consistent with best practices across Canada helps us identify opportunities for early interventions, treatment and supportive care.”
In the U.S., newborn screening for SMA has been implemented in 43 states to date, according to the nonprofit advocacy organization Cure SMA.