Riluzole Shows Promise of Improving Motor Function
Effective in patients with acute traumatic spinal cord injury when treatment is started within 12 hours of injury
(Short Hills, NJ) -- July 19, 2013 -- In a Phase 1 study of the safety, pharmacology and exploratory preliminary efficacy of the drug riluzole, conducted by the North American Clinical Trials Network (NACTN) researchers found that riluzole administered orally within 12 hours of acute traumatic injury was well tolerated and improvement in motor scores of patients with cervical injuries was manifest at 90 days post-injury. The greatest effect was in patients who had some sensation present below the spinal level of injury.
The research is published in the online version of the peer-reviewed Journal of Neurotrauma, and the abstract is available here.
NACTN is a consortium of 10 clinical centers composed of neurosurgery department faculty and staff at university affiliated hospitals, a biometry and a pharmacology center. NACTN was formed by the Christopher & Dana Reeve Foundation to speed the testing of therapies for spinal cord injury.
Riluzole is approved for treating patients with amyotrophic lateral sclerosis (ALS). However, this Phase I trial is the first to examine its safety, pharmacokinetics and preliminary efficacy in patients with traumatic spinal cord injury. A larger, Phase 2/3 efficacy trial will commence this fall.
"We are encouraged by the Phase I results," said Dr. Robert Grossman, NACTN's Principal Investigator and professor of neurosurgery at Houston Methodist Hospital. "There were no serious adverse events attributable to riluzole. The data suggests that riluzole may be able to preserve motor function in patients with acute cervical injuries, which might make them better able to respond to regenerative and other therapies applied at later stages of their recovery."
The Phase 1 trial included 36 patients with traumatic acute spinal cord injury from C4 to T11. Most patients were male (83 percent) and had a cervical injury (78 percent).
Riluzole was administered orally every 12 hours for 14 days. The drug has multiple mechanisms of action including blocking of ion channels in cells thereby reducing damage that would be caused by excessive entry of sodium and calcium ions into the cells.
Susan Howley, Executive Vice President of Research at the Christopher & Dana Reeve Foundation, commented "It is incredibly rewarding to see conclusive research realized from the creation of the NACTN, which we formed specifically to hasten the testing of SCI therapies. While we are encouraged by the progress, we need to continue exploring new treatment therapies in the hope of -- one day -- finding cures for SCI, both acute and chronic."
The Phase 2/3 trial -- called RISCIS, for Riluzole in Spinal Cord Injury Study – will include 350 patients with cervical injuries, the group that seems to benefit most from the drug, at up to 35 clinical centers. This trial is being led by Michael Fehlings, M.D., Ph.D., professor of neurosurgery and medical director of the Krembil Neuroscience Center at the University of Toronto. "Riluzole appears to be safe in traumatic acute spinal cord injury, and the progress of neurological recovery appears promising," said Fehlings.
The RISCIS trial, set to begin this fall, will take two years to enroll all patients. In addition to further establishing safety and efficacy, the study seeks to determine the theraputic blood level of riluzole, to optimize the oral dose. The RISCIS study is being funded collaboratively by Department of Defense support for NACTN and by AOSpine North America, an international education and research society of 6,000 physicians caring for spinal disorders that has funded studies related to musculoskeletal science, such as arthritis, spinal cancer, spinal deformity and trauma.