William Smarts, 58, woke up in his bed last week in Vidalia, Ga., and knew he was in trouble.
“My arm, I couldn’t move my hand or get to the phone or nothing,” he said, as a stroke had paralyzed the left side of his body. He was airlifted to AU Medical Center, but he still didn’t arrive in time to receive a clot-busting drug or other interventions for stroke.
The man standing in his hospital room listening to his story, Dr. David Hess, is hoping to change that.
Hess, the chairman of the Department of Neurology at Augusta University, was the lead clinical principal investigator on using a type of stem cell treatment called MultiStem Therapy for stroke. He presented the results of patients one year after treatment on Wednesday at the International Stroke Conference of the American Heart Association.
The stem cells are similar to adult stem cells that occur naturally in the body, and 120 patients at 33 centers in the U.S. and United Kingdom were randomized to either receive the therapy or placebo.
“This is the first stem cell trial in the world that included over 100 patients that I know of,” Hess said. “This is really the first big attempt.”
The manufacturer, Athersys, designed the product to be a universal “off the shelf” treatment, but because the cells had to be processed in a blood bank, the original treatment window of 12 to 36 hours after the stroke had to be extended out to 48 hours in order to enroll enough patients, Hess said.
The treatment was “well tolerated” but because of the larger treatment window there was no “statistically significant” difference from the placebo group in all of the treated patients. But there were encouraging signs in the treatment group under further analysis, Hess said.
There were fewer deaths, less disability, less serious adverse events and fewer infections in the treatment group, he said. Fewer infections over time is important in stroke, Hess said.
“One of the things that we think happens after stroke, in the weeks and months after stroke, you actually get immunosuppression because you deplete immune cells from the spleen,” he said. “That’s why there may be an increased risk of infection. If anything, the MultiStem cells seem to be favorable in all of those safety parameters.”
One of the ways the stem cells are believed to help is in stopping a damaging inflammatory effect after the stroke from the patient’s immune system and encouraging the body’s regenerative process to kick in.
“The cells are sensing what is going on, reacting to the environment and responding to the environment,” Hess said. “So that is important.”
In other data presented at the conference, the treated patients spent less time in the intensive care unit and had fewer hospitalizations “so there are a lot of cost savings,” he said.
The company has changed the process of giving the therapy, which are around 1.2 billion cells per dose through an IV, so the next clinical trial should proceed much more smoothly, Hess said.
“This is a learn study, not a confirm study,” Hess said. What is needed is a follow-up study of similar or larger size, in the U.S. or Europe or both, to confirm the results, he said.
“Because that data is promising and we are still in a window where there is nothing in stroke (acute treatment) at 24 to 36 hours, it should be pursued,” Hess said.
The next step for Athersys, however, may come in Japan. Earlier this year, the company announced an agreement with the Japanese stem cell company Healios that would allow that company to pursue clinical trials there.
“In Japan, the road to get a stem cell approved is much, much easier,” Hess said.
The potential for the drug in treating stroke is still promising and it would have many advantages over the current acute therapy, he said. The time window for treatment could be extended out to 36 hours, the cells could be stocked in a pharmacy and thawed when needed, it would not need a neurologist to sign off on treatment as the clot-busting therapy requires, and it could conceivably be given by any doctor on staff without having to transfer the patient to a major stroke center.
“It would potentially be a community hospital drug,” Hess said.