The Phase II trial is a randomized repeat-dosing, open-label, multi-center study designed to evaluate the effect of intramuscular administration of SB-509 on the progression of the disease in subjects with amyotrophic lateral sclerosis (ALS), as measured by the ALS functional rating scale-revised, a validated rating instrument for monitoring the progression of disability in patients with ALS. Efficacy of SB-509 will be evaluated by comparing the rate of ALS disease progression in subjects treated with SB-509 in this study to historical placebo controls.
In addition to gathering data on safety and tolerability of SB-509 in subjects with ALS, data will be collected to evaluate the effect of SB-509 on additional clinical measures. These measures include forced vital capacity, a test of lung function; neurophysiologic index, a measure of neurologic impairment; manual muscle test, a test of muscle strength; and survival. Finally, the study will also evaluate stem cell mobilization in subjects with ALS receiving SB-509.
A total of 40 subjects with ALS will be enrolled in this trial and randomized into one of two treatment cohorts. The first cohort of 35 subjects will receive 60mg of SB-509 in a divided dose into muscles in the arm, leg and along the spine on both sides of the body. A second cohort of five subjects will receive 60mg of SB-509 in a divided dose into the muscles in the lower limb in both legs.
Each subject will receive a total of two treatments of 60mg of SB-509 intramuscularly three months apart on day zero and day 90. The study will be carried out over 11 months, including two months for screening, three months for two study treatments, and six months of follow-up after administration of the final dose.
Sangamo’s drug, SB-509, is an injectable formulation of a plasmid encoding a zinc finger DNA-binding protein transcription factor designed to upregulate the expression of the gene encoding vascular endothelial growth factor.