New Study Shows Stem Cells Can Be Given Safely to Stroke Patients with Catheterization Procedure

A national study led by a University of Miami Miller School of Medicine researcher has shown that the delivery of stem cells to the brain using a tiny catheter introduced through the groin into the carotid artery in the brain is safe for patients with strokes.

Joshua M. Hare, M.D., with Dileep R. Yavagal, M.D.
Joshua M. Hare, M.D., with Dileep R. Yavagal, M.D.

“This groundbreaking first randomized clinical trial of intra-arterial cell delivery establishes that this minimally invasive approach to deliver cells to the area of stroke in the brain shortly after a stroke is both feasible and safe,” said Dileep R. Yavagal, M.D., professor of clinical neurology and neurosurgery, and director of Interventional Neurology at UM/Jackson Memorial Hospital and University of Miami Hospital and Clinics. “Now, we hope to conduct a larger study to establish the potential benefits of using stem cells to help stroke patients recover their function.”

Dr. Yavagal was national co-principal investigator of the multicenter study and principal investigator at the Miami site with co-principal investigator Jose Romano, M.D., professor of clinical neurology and chief of the Stroke Division. Dr. Yavagal was one of the lead authors of the study, “A Phase 2 Randomized, Sham-Controlled Trial of Internal Carotid Artery Infusion of Autologous Bone Marrow–Derived ALD-401 Cells in Patients With Recent Stable Ischemic Stroke (RECOVER-Stroke),” which was published in January in the journal Circulation.

“The RECOVER-Stroke Trial is a major step forward in clearly showing the safety of a catheter-based delivery of stem cells in a targeted manner to the injured brain in stroke,” said Joshua M. Hare, M.D., Louis Lemberg Professor of Medicine and founding director of the Miller School’s Interdisciplinary Stem Cell Institute (ISCI). “I commend Dr. Yavagal and his colleagues for pursuing this critical step moving this promising approach for regenerative medicine for stroke to the bedside.”

Calling the trial “a major advance in the development of stem cells for stroke recovery,” Ralph L. Sacco M.D., professor and Olemberg Chair of Neurology, executive director of the McKnight Brain Institute, and senior associate dean for clinical and translational science, added, “The Miller School continues to be a leading center with both animal and human translational stroke research in this field.”

Noting that Dr. Yavagal was recently named director of ISCI’s Neurological Platform, Dr. Hare said, “His ongoing work and vision to grow the platform with investigators with expertise in developing cell therapy for other neurological diseases and conditions will be invaluable for ISCI, UM, and patients worldwide.”

In the RECOVER-Stroke clinical trial, 48 patients were enrolled approximately two weeks after an ischemic stroke, a brain injury that currently has no approved treatments to enhance recovery. Twenty-nine patients were treated with autologous stem cells extracted from each patient’s bone marrow nine to 11 days after the stroke. These adult stem cells were then transported to the brain through the carotid artery using an interventional catheterization procedure done through a small hole in the groin artery. The other 19 patients underwent a sham procedure as a control group.

“Stem cells are the building blocks of our bodies, and this trial used the body’s natural arterial pathway to deliver them directly to the injured brain tissue, where they potentially could enhance recovery,” Dr. Yavagal said.

He added that the new study addressed a concern that the stem cells by themselves could act as tiny emboli or clots, blocking arterial blood circulation to the brain.

“That issue was set to rest by our study, as none of the treated patients had a worsening in their stroke score after getting the cells,” he said. Also, no other safety concerns related to the cells were seen in the study that followed patients for one year with clinical examinations and MRIs. “There were no significant differences between the groups on any of the measures of benefit,” Dr. Yavagal said. “This is not unexpected in an initial safety study with a small number of patients.”

The safety study provides a framework for a potentially larger study to establish whether stem cells transported in this minimally invasive procedure can help repair damaged brain tissue.

“That would be the next step in the research,” said Dr. Yavagal. “Ideally, stem cells from healthy donors could be delivered between 24 and 36 hours after a stroke to minimize tissue damage.”

Tags: catheterization, RECOVER-Stroke, stem cells