By: 27 March 2017
New treatment for spinal muscular atrophy safe for infants

Infants as young as five weeks old with the most severe form of spinal muscular atrophy (SMA) can be treated safely with nusinersen, according to research published online in The Lancet. Investigational treatment slowed progression of the disease, improved survival and in some cases demonstrated remarkable improvement in muscle function.

The multi-site, phase two, open-label trial of patients with infant-onset SMA – a leading genetic cause of infant mortality – targeted the SMN2 gene with a tiny fragment of DNA called an anti-sense oligonucleotide (ASO), injected directly into the spinal fluid of 20 participating infants. The ASO gets absorbed into nerve cells of the spinal cord and brain and promotes increased production of a critical protein that is deficient in babies with SMA. Not only was the series of nusinersen treatments delivered safely to the fragile babies, but in the majority of patients it was found to halt progression of the disease and in many cases improve motor function, sometimes enabling children to gain skills not seen in SMA type 1 – sitting, rolling over and standing – as well as improving survival without dependence upon the continuous use of a ventilator.

The study builds on the body of research supporting the effective use of nusinersen, one of the first therapies for SMA, developed by Ionis Pharmaceutical in partnership with Biogen. Biogen has submitted a nusinersen for approval in the USA by the Food and Drug Administration and in Europe by the European Medicines Agency. The company is also preparing for the potential launch of nusinersen, to be sold as Spinraza, early in 2017.

“With nusinersen, these infants are not only living longer, but they’re living better,” said Richard Finkel, lead author of the study and chief of neurology at Nemours Children’s Hospital in Orlando. “SMA is no longer a death sentence for infants. This treatment is by no means a cure, but it is more than we’ve ever been able to offer these families before.”

Finkel and his team are continuing to build on the safety profile of nusinersen through several ongoing clinical trials at Nemours Children’s Hospital. NURTURE is an open-label, ongoing phase 2 clinical trial in pre-symptomatic infants with SMA who are up to six weeks of age at time of first dose, to determine whether treatment before symptoms begin would prevent or delay the onset of SMA.

Source: Medical Xpress


Reference: Finkel, R.S., et al. (2016) Treatment of infantile-onset spinal muscular atrophy with nusinersen: a phase 2, open-label, dose-escalation study. The Lancet.