Valproate may improve strength and function in patients with type III/IV spinal muscle atrophy.

Spinal muscular atrophy (SMA) is a recessively inherited motor neuron disease caused by deficient survival motor neuron (SMN) protein. Valproate increases SMN protein in vitro by increasing transcription of SMN2 genes. The authors treated seven adult patients with SMA type III/IV with valproate for a mean duration of 8 months. The treated patients with SMA had increased quantitative muscle strength and subjective function. Further trials of valproate treatment for SMA type III/IV are warranted.