SMA - Spinal Muscular Atrophy

An Open Label Individual Patient (OLIP) Study of Nusinersen (BIIB058) in a Participant with Spinal Muscular Atrophy Who Previously Participated in an Investigational Study with Nusinersen

This study is an open label individual patient study of the drug Nusinsersen.

Spinal muscular atrophy (SMA) is a genetic disorder that is known to cause damage to specialised nerve cells, called motor neurons. These neurons are located in the spinal cord and transfer signals from the brain to muscles to allow movement. A lack of nerve signalling leads to progressive muscle weakness and wasting, which affects a person' mobility, breathing and swallowing. Treatments have only recently been developed and there are now three commercially available drugs for SMA. These drugs improve survival and mobility of patients with SMA. Patients are surviving longer but other problems apart from muscle weakness have been found in patients with SMA that may be related to SMA. One of the additional problems in SMA investigators have noted is poor bone health. Investigators observed low impact fractures, vertebral fractures, and reduce bone density from a very early age in our cohort. Investigators however do not know if this is related to reduced mobility and subsequent loss of muscle loading of bone in SMA or if this is a direct effect of reduced Survival Motor Neuron (SMN) protein. The natural history of bone health in SMA patients is not well described. Investigators also do not know if the drugs used to treat SMA improves bone health. The additional need of high dose steroids in patients receiving onasemnogene abeparvovec (OA) may also reduce bone health in those receiving this therapy. There are also no licensed treatments for the management of fragile bones (osteoporosis) in children or guidelines or consensus on management of osteoporosis or fractures in SMA. Investigators want to study the bone health in paediatric patients with SMA in UK by looking at the incidence and type of fractures and comparing this in the different drug therapy groups against those who do not receive a SMA drug, assess impact of duration of steroid use and bone health in those that received onasemnogene aberparvovec, and to determine what needs to be measured and recorded to assess bone health most effectively in SMA. To do this investigators will be utilising data collected nationally through the SMA REACH UK network already and study medical records on data that is felt important but not collected by the SMA REACH UK database. Investigators are only planning to review existing information - no additional tests will be performed.

The aim of this study is to describe national trends over the past 10 years in patients receiving invasive home mechanical ventilation (HMV) in Denmark. This includes indications for invasive HMV, diagnostic groups, and one-year mortality.

This trial employs a multicenter, randomized, open-label, standard-of-care-controlled design and plans to enroll 50 patients with Type 2 SMA aged 2 to 12 years who have previously received nusinersen. The primary objective of the trial is to evaluate the efficacy of GC101 in treating Type 2 SMA. The secondary objectives are to assess the efficacy, safety, and pharmacokinetic (PK) profile of GC101 in treating Type 2 SMA.