The University of Louisville is now enrolling qualifying patients in a nationwide phase III clinical trial to study whether a patient’s own stem cells could help lessen the effects of angina.

Known as the “RENEW” trial, the study is recruiting patients who have severe refractory angina, characterized by intense and chronic chest discomfort that does not respond to conventional medical treatment or surgery.

The condition is an indicator of chronic myocardial ischemia (CMI). One of the most severe forms of coronary artery disease, CMI causes significant long-term damage to the heart muscle and disability to the patient.

Eligible study participants are men or women, ages 21 to 80, who have chronic, refractory angina that has not responded to conventional therapies or surgical interventions. Exclusion criteria include a cardiac-related hospitalization in the previous 60 days or a coronary artery bypass graft procedure within the previous six months.

In the trial, participants first will participate in a series of exercises that will provide a baseline measurement of their heart function and capacity. They also will keep a diary noting the frequency and severity of their angina attacks.

Patients then will provide blood samples that will be processed to extract stem cells that express what is known as the “CD34+” stem cell. While scientists have yet to discover the CD34+ stem cell’s full function, it is known as a marker, or indicator, of stem cells and bears a relationship to the vascular system.

The extracted CD34+ stem cells then will be injected back into target areas of the patient’s heart. After several follow-up visits, patients will undergo the same exercise series and report on their angina condition to measure the effects of the treatment. Patients will be followed for approximately two years.

The trial is being initiated based on the results of a previous phase II trial indicating injections of adult patients’ own CD34+ stem cells improved exercise tolerance time and reduced reports of angina episodes in patients with chronic, severe refractory angina.

The trial is expected to enroll about 440 patients, who will be randomized to one of three arms: treatment arm, active-control arm and unblinded standard-of-care arm.