CARNIVAL Type I: Valproic Acid and Carnitine in Infants With Spinal Muscular Atrophy (SMA) Type I

Spinal muscular atrophy (SMA) is a genetic disorder that results in severe muscle weakness. It is one of the most common conditions causing muscle weakness in children. Patients with SMA most often develop weakness as babies or young children. Most people with SMA gradually lose muscle strength and abilities over time. Babies with the severe infantile form of SMA, SMA type I, usually lose abilities and strength quickly over a few weeks or months. Valproic acid (VPA) is a medicine that has been used for many years to treat patients with epilepsy. Recent research suggests that VPA may be able to upregulate expression of a backup copy of the SMN gene in SMA patient cell lines. In addition, some preliminary data suggests it may prolong survival in animal models of SMA. Because VPA can deplete carnitine in children with SMA Type I, carnitine is added to help prevent possible toxicity. In this multi-center trial, we will evaluate the effects of VPA/carnitine on infants with SMA type I. A variety of outcome measures, including assessment of safety, will be performed at each study visit to follow the course of the disease. The protocol includes two baseline visits over a period of two weeks, two clinical assessments on medication at 3 and 6 months, and then 6 months additional followup via telephone. Total duration of the study will be approximately 12 months.