Injecting modified, human, adult stem cells directly into the brains of chronic stroke patients proved not only safe but effective in restoring motor function, according to the findings of a small clinical trial led by Stanford University School of Medicine investigators. Approximately 1/3 of the patients received their treatment at the University of Pittsburgh Medical Center (UPMC). The Pitt portion of the study was under the leadership of Lawrence Wechsler, MD, Henry B. Higman Professor and Chair, Department of Neurology, and Vice President for Telemedicine, UPMC.
The patients, all of whom had suffered their first and only stroke between 6 months and 3 years before receiving the injections, remained conscious under light anesthesia throughout the procedure, which involved drilling a small hole through their skulls. The next day they all went home.
Although more than 3/4 of them suffered from transient headaches afterward — probably due to the surgical procedure and the physical constraints employed to ensure its precision — there were no side effects attributable to the stem cells themselves, and no life-threatening adverse effects linked to the procedure used to administer them, according to a paper, published online in Stroke, that details the trial’s results.
The promising results set the stage for an expanded trial of the procedure now getting underway. They also call for new thinking regarding the permanence of brain damage, said Gary Steinberg, MD, PhD, professor and chair of neurosurgery, Stanford. Dr. Steinberg, who has more than 15 years’ worth of experience in work with stem cell therapies for neurological indications, is the paper’s lead and senior author.
“This was just a single trial, and a small one,” cautioned Dr. Steinberg, who led the 18-patient trial and conducted 12 of the procedures himself. (The rest were performed at the University of Pittsburgh Medical Center.) “It was designed primarily to test the procedure’s safety. But patients improved by several standard measures, and their improvement was not only statistically significant, but clinically meaningful. Their ability to move around has recovered visibly. That’s unprecedented. At 6 months out from a stroke, you don’t expect to see any further recovery.”
Some 800,000 people suffer a stroke each year in the United States alone. About 85 percent of all strokes are ischemic: They occur when a clot forms in a blood vessel supplying blood to part of the brain, with subsequent intensive damage to the affected area. The specific loss of function incurred depends on exactly where within the brain the stroke occurs, and on its magnitude.
Although approved therapies for ischemic stroke exist, to be effective they must be applied within a few hours of the event — a time frame that often is exceeded by the amount of time it takes for a stroke patient to arrive at a treatment center.