Kugelberg Welander Spinal Muscular Atrophy Medication

Updated: Sep 01, 2021
  • Author: Joyce L Oleszek, MD; Chief Editor: Stephen Kishner, MD, MHA  more...
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Medication

Medication Summary

Numerous treatment trials for spinal muscular atrophy (SMA) have been described or are currently underway. [27]  Based on the role that mutations or deletions in SMN1 play in the development of SMA, treatments have been developed that are directed at the gene’s expression. In 2016, nusinersen became the first such agent to obtain approval from the US Food and Drug Administration (FDA). It is given intrathecally, with four loading doses administered, as well as a maintenance dose every 4 months. [28, 29] The best outcomes have been found when the drug is provided at a very young age. In 2019, onasemnogene abeparvovec-xioi became the next agent to receive FDA approval, albeit only for children under age 2 years. [30] Considering its age limitation, the drug, administered as a one-time intravenous (IV) injection, may not be relevant to the treatment of many patients with Kugelberg Welander SMA, since they are typically diagnosed at an older age. Risdiplam received FDA approval in 2020; it is a daily oral medication that can be given to SMA patients aged 2 months or older. [31]

Medications being studied for upregulation of SMN2 protein production or for increase of exon 7 inclusion include phenylbutyrate, valproic acid, suberoylanilide hydroxamic acid, and hydroxyurea. The neuroprotective medications being investigated, including gabapentin and riluzole, are thought to provide protection from oxidative stress. Albuterol has been studied for its trophic/anabolic effects. Exercise therapy in rats has shown modest improvement in survival and modest decrease in motor neuron loss. Treatment with stem cells is also an area undergoing further study.

A single study from the Russian literature in 1980 suggested that lithium may have a role in slowing the disease progression, but this has not been corroborated. Further studies are needed to investigate this. [32]

A study using thyrotropin-releasing hormone as a treatment for SMA types II and III in children showed promising results. More studies are warranted to further investigate this possible treatment. [33]

Merlini and colleagues performed a multicenter, randomized, controlled trial of gabapentin versus no treatment in 120 patients with SMA type II or III for 12 months. [34] A significant improvement in lower extremity, maximum, voluntary isometric contraction was seen.