Valproic Acid and Carnitine in Patients With Spinal Muscular Atrophy

Inclusion Criteria: Cohort 1 * Confirmed genetic diagnosis of 5q SMA * SMA 2 or non-ambulatory SMA 3: all subjects must be able to sit independently for at least 3 seconds without support * Age 2 to 8 years at time of enrollment Cohort 2 * Confirmed genetic diagnosis of 5q SMA * SMA subjects (SMA types 2 or 3) who can stand independently without braces or other support for up to 2 seconds, or walk independently * Age 3 to 17 years at time of study enrollment Exclusion Criteria: Cohort 1 * Need for BiPAP support \> 12 hours per day * Spinal rod or fixation for scoliosis or anticipated need within six months of enrollment * Inability to meet study visit requirements or cooperate reliably with functional testing * Coexisting medical conditions that contraindicate travel, testing or study medications * Use of medications or supplements which interfere with valproic acid or carnitine metabolism within 3 months of study enrollment. * Current use of either VPA or carnitine. If study subject is taking VPA or carnitine then patient must go through a washout period of 12 weeks before enrollment into the study * Body Mass Index \> 90th % for age Cohort 2 * Spinal rod or fixation for scoliosis or anticipated need within six months of enrollment * Inability to meet study visit requirements or cooperate with functional testing * Transaminases, amylase or lipase \> 3.0 x normal values, WBC \< 3.0 or neutropenia \< 1.0, platelets \< 100 K, or hematocrit \< 30 persisting over a 30 da…