A magnified view of a CD34+ stem cell, a blood-forming stem cell derived from bone marrow, which can develop into new blood vessels. CD34+ stem cells are under investigation as a possible treatment for chronic myocardial ischemia.
March 5, 2012 — Baxter International Inc. announced that it initiated a phase III pivotal clinical trial to evaluate the efficacy and safety of adult autologous (individual’s own) CD34+ stem cells to increase exercise capacity in patients with chronic myocardial ischemia (CMI).
Chronic myocardial ischemia (CMI) is one of the most severe forms of coronary artery disease, causing significant long-term damage to the heart muscle and disability to the patient. It is often diagnosed based on symptoms of severe, refractory angina, which is severe chest discomfort that is unresponsive to conventional medical management or surgical interventions.
“The prospect of using a person’s own adult stem cells to restore and repair blood flow in CMI is a very exciting concept based on a biological regenerative approach,” said Norbert Riedel, Ph.D., Baxter’s chief science and innovation officer. “The goals of this phase III trial are aligned with Baxter’s overall mission to develop life-saving and life-sustaining therapies and it will help us determine if the therapy can make a meaningful difference for CMI patients.”
The trial will enroll approximately 450 patients across 50 clinical sites in the United States, who will be randomized to one of three arms: treatment with their own autologous CD34+ stem cells, treatment with placebo (control), or unblinded standard of care. The primary objective is to evaluate the efficacy of treatment with CD34+ stem cells to improve the functional capacity of patients with CMI, as measured by a change in total exercise capacity at 12 months following treatment. Secondary objectives include reduced frequency of angina episodes at 12 months after treatment and the safety of targeted delivery of the cells.
After stem cell mobilization, apheresis (collecting the cells from the body) and cell processing, participants will receive CD34+ stem cells or placebo in a single treatment via 10 intramyocardial injections into targeted areas of the heart tissue. Efficacy will be measured by a change in total exercise capacity during the first year following treatment and safety data will be collected for two years. Stem cell processing will be conducted in GMP facilities in the United States by progenitor cell therapy (PCT), a subsidiary of NeoStem, Inc.
This trial is being initiated based on the phase II data, which indicated that injections of patients’ own CD34+ stem cells may improve exercise capacity and reduce reports of angina episodes in patients with chronic, severe refractory angina.
“The phase II trial provided evidence that this strategy, leveraging the body’s own natural repair mechanisms, can improve exercise capacity and reduce chest pain, the first time these endpoints have been achieved in a population of patients who have exhausted conventional treatment options,” said Douglas Losordo, M.D., vice president of new therapeutic development at Baxter.
CD34+ cells, which are blood-forming stem cells derived from bone marrow, are comprised of endothelial progenitor cells (EPCs), which develop into new blood vessels. Previous preclinical studies investigating these cells have shown an increase in capillary density and improved cardiac function in models of myocardial ischemia.
For more information: www.renewstudy.com, www.clinicaltrials.gov
June 11, 2025 
