FDA Approves First Treatment for Spinal Muscular Atrophy

US Spinraza nusinersen carton and vial
US Spinraza nusinersen carton and vial
The US FDA has approved the first drug for the treatment of spinal muscular atrophy, a genetic disease that often results in premature death.

The US Food and Drug Administration (FDA) recently approved1 the first-ever drug for the treatment of spinal muscular atrophy (SMA). The drug, nusinersen (Spinraza™), is an intrathecal injection approved for use in adult and pediatric patients.

SMA is a genetic disease associated with severe, progressive muscular atrophy and weakness that can lead to paralysis and respiratory problems. Patients diagnosed with SMA type 1, the most severe form, typically do not live longer than 2 years without respiratory support.

The drug, which was granted fast track designation, priority review, and orphan drug designation by the FDA, was evaluated based on results from several open-label and sham-controlled clinical trials,2 including an interim analysis of the phase 3 ENDEAR trial (ClinicalTrials.gov NCT02193074), which evaluated motor function in 121 patients with infantile-onset SMA. Of the patients included in the interim analysis, 40% (n = 82/121) who were treated with nusinersen demonstrated improvements in motor milestones compared with none of the control patients.

The most common adverse effects of treatment with nusinersen were upper and lower respiratory infection and constipation. Health care providers should also be aware that treatment with the drug may be associated with low blood platelet counts and renal toxicity.

Nusinersen will be available to health care providers in January 2017. Biogen has also launched SMA360°™, a patient information portal that addresses nonmedical barriers to access to nusinersen for those prescribed the drug.

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  1. FDA approves first drug for spinal muscular atrophy [news release]. FDA Newsroom; December 23, 3016. www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm534611.htm. Accessed January 6, 2017.
  2. US FDA approves Biogen’s SPINRAZA™ (nusinersen), the first treatment for spinal muscular atrophy [news release]. Cambridge, MA: Biogen newsroom; December 23, 2016. http://media.biogen.com/press-release/neurodegenerative-diseases/us-fda-approves-biogens-spinraza-nusinersen-first-treatment. Accessed January 6, 2017.