Nusinersen, an antisense oligonucleotide, is the first and only FDA-approved drug for children and adults with spinal muscular atrophy (SMA). The illness is a rare genetic disease that causes progressive muscular weakness and atrophy due to motor neuron loss in the spinal cord and lower brain stem.
Marketed as Spinraza, the drug is given via intrathecal injection directly into cerebrospinal fluid surrounding the spinal cord. It received a priority review as well as the FDA’s fast track and orphan drug designations, which expedite approval of drugs that fill unmet needs for serious and rare diseases.
Voelker R. First Drug for Rare Genetic Disease. JAMA. 2017;317(5):466. doi:10.1001/jama.2017.0028