A recent study suggests an alternative procedure for delivering the drug nusinersen to patients being treated for spinal muscular atrophy. Although more research needs to be done to estabilish its safety and efficacy, these results are promising. For more detailed information, you can click here to view the original study published in the Journal of Pediatric Orthopaedics at the PubMed website.
About Spinal Muscular Atrophy
Spinal muscular atrophy (SMA) is a rare and inherited neuromuscular condition that is characterised by progressive muscle weakness and atrophy. The condition may affect peoples’ ability to walk, move their arms, head, neck, breathe, and swallow, amongst other symptoms.
According to SMA Support UK, there is a spectrum in how severely SMA affects people, and SMA is often categorised into several ‘types’. Types 1, 2, and 3 typically begin at certain points throughout childhood, while type 4 is considered to be adult-onset. However, there is also a lot of variation within these types, and in recognition of this some people may further subcategorise types with a, b, or c (for example, Type 3 a).
The main types of SMA are caused by a lack of the SMN protein, typically linked to genetic changes to the SMN1 gene.
About Nusinersen
The drug nusinersen (SpinrazaTM) was approved for the treatment of Types 1, 2, and 3 of SMA by the US Food and Drug Administration in December 2016. Since then, the European Commission approved nusinersen in June 2017 for the treatment of people with 5q SMA (referring to a type of genetic alteration that spans Types 1, 2, 3, and 4).
The drug is designed to help the body produce more functional SMN protein, and clinical studies have shown that it can help people with SMA to reach and maintain physical milestones, and may prolong life.
The information about nusinersen is sourced from SMA Support UK’s website, and you can read more about the drug and how it works by clicking here.
Delivering Nusinersen
According to the recent study, some patients who are likely to benefit from treatment with nusinersen face difficulties with the drug delivery. Nusinersen is delivered by healthcare professionals through repeat lumbar puncture, but changes to the spine, such as scoliosis, can problematize safe delivery.
The Study
To investigate alternative delivery options, a team of researchers designed a new subcutaneous intrathecal catheter (SIC) system. This was then tested in ten patients with SMA aged between 5 and 30. Each patient was given three doses of the drug.
It took two hours or less to implant the experimental device, and, following this, all nusinersen doses were given within 20 minutes. At this point, the SIC needs to be investigated further in larger and longer-lasting studies before firm conclusions about its efficacy and safety can be drawn. However, the researchers write that so far, the SIC appears to be “relatively safe”, and may have the potential to significantly reduce the costs of delivering nusinersen.
For more detailed information about the study, you can view the abstract here.
