Olfactory ensheathing cells in chronic ischemic stroke: A phase 2, double-blind, randomized, controlled trial

Olfactory ensheathing cells (OECs) have shown promising results for patients with neurologic diseases in non-double-blind, placebo control studies. Thirty patients with a unilateral ischemic stroke of more than a year were enrolled in a phase 2, multicenter, randomized, double-blind, and placebo-controlled cell therapy trial with a subsequent 12-month follow-up. The primary therapeutic objective has shown that after 12 months, there were significant differences in National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS) and Barthel Index (BI) assessment scores among the OEC group, Schwann cell group and placebo medium group at one-year follow-up. The second therapeutic objective found that there were significant differences in NIHSS, mRS, and BI assessment scores when comparing the endpoint data with the baseline data in the OEC group. There was neither hypersensitivity reaction nor adverse event. The results of this multicenter, randomized, double-blind, and placebo-controlled study indicate that injecting OECs into the olfactory sub-mucosa have neurorestorative effects, which can improve the quality of life for patients with chronic ischemic strokes without serious side effects.