A Mayo Clinic Phase II trial shows engineered stem cell injections restore partial motor function in 12 of 20 patients with complete spinal cord injuries.
The Mayo Clinic has published results of a Phase II clinical trial demonstrating that engineered stem cell therapy can restore meaningful motor function in patients with complete spinal cord injuries. Of 20 patients enrolled in the study, 12 regained partial voluntary movement below the injury level, a result that would have been considered medically impossible just a decade ago.
The therapy uses induced pluripotent stem cells (iPSCs) derived from the patient's own blood cells, which are reprogrammed and differentiated into neural progenitor cells. These cells are then combined with a biodegradable scaffold infused with growth factors and injected directly into the injury site during a minimally invasive surgical procedure.
Dr. Mohamad Bydon, the neurosurgeon who led the trial, explained that the key innovation was the scaffold design. Previous stem cell therapies for spinal cord injury failed partly because transplanted cells could not survive in the hostile environment of the injured spinal cord. The scaffold provides structural support and creates a microenvironment that promotes cell survival, integration, and the formation of new neural connections.
Functional assessments performed at 6 and 12 months post-treatment showed that the 12 responding patients gained an average improvement of 2 grades on the American Spinal Injury Association (ASIA) Impairment Scale. Several patients who were classified as ASIA-A (complete paralysis) progressed to ASIA-C (motor function present below the injury level), enabling them to perform basic movements such as knee bending and ankle dorsiflexion.
Electrophysiological studies confirmed the formation of new functional connections across the injury site. Nerve conduction studies demonstrated measurable signals passing through regions that previously showed no electrical activity, indicating that the transplanted cells had successfully bridged the gap in damaged neural tissue.
The results have generated intense interest in the spinal cord injury community. Approximately 300,000 people live with spinal cord injuries in the United States, with 18,000 new cases occurring annually. Currently, no treatment exists that can restore function after a complete spinal cord injury.
A Phase III multicenter trial is being planned to confirm these results in a larger patient population. The research team is also investigating whether earlier intervention, within weeks of injury rather than years, might produce even more robust recovery.