Spinraza is an approved treatment for spinal muscular atrophy, the most common genetic fatal disease in infants. SMA1 is a rare neuromuscular disorder characterised by loss of lower motor neurons and progressive muscle wasting, often leading to early death.
The disorder is caused by a genetic defect in the SMN1 gene, which encodes SMN, a protein widely expressed in all eukaryotic cells (that is, cells with nuclei, including human cells) and necessary for survival of motor neurons. Lower levels of the protein results in loss of function of neuronal cells in the anterior horn of the spinal cord and subsequent system-wide atrophy of skeletal muscles.
Spinal muscular atrophy manifests in various degrees of severity, all of which include levels of progressive muscle wasting and mobility impairment. Proximal muscles, arm and leg muscles that are closer to the torso and respiratory muscles are affected first. Other body systems may be affected as well, particularly in early-onset forms of the disorder. SMA is the most common genetic cause of infant death.
Spinal muscular atrophy is an inherited disorder and is passed on in an autosomal recessive manner. In December 2016, nusinersen (marketed as Spinraza) became the first approved drug to treat SMA while several other compounds remain in clinical trials. As reported by the Guardian, Spinraza is available in 24 counties, including Scotland, but it cannot be accessed by patients in the NHS in England, Wales and Northern Ireland.
Biogen, the drug’s manufacturer, introduced a global compassionate plan for children with SMA1 to ensure temporary access to the drug. According to the Guardian however, the Biogen plan stopped November of 2018, meaning newly diagnosed babies no longer had access to Spinraza.
A group of UK physicians recently published that they along with patient advocacy groups such as Muscular Dystrophy UK and SMA UK, are strongly advocating the UK NHS to “show flexibility and recommend the effective treatment for SMA patients. In the long-run, there must be an overhaul of this convoluted appraisal process, which is not fit-for-purpose for treatments of rare conditions in England.”