Pivotal heart disease stem cell trial launched

A major clinical trial to investigate a stem cell treatment for chronic ischemic heart disease (IHD) — a leading cause of death around the world — has begun in the US.

The treatment — developed by the life sciences company Baxter — uses patients' own stem cells to repair damage to the heart. IHD is a condition where the blood supply to the heart is reduced, usually due to narrowing or blockage of the arteries that supply the heart with blood.

Were this phase III trial to be successful it would represent the last step in the clinical development  process before submission by the regulatory authorities and, hopefully, approval and commercialisation. Unlike some of the other recent stem cell trials to repair heart damage (reported in BioNews 645, 634 and 624) this procedure uses stem cells from a patient's bone marrow that are normally involved in the creation of new blood vessels.

In the procedure these CD34+ cells are stimulated to grow and multiply, before being induced to enter the bloodstream. The cells are then collected, processed and injected into targeted areas of the heart.

Around 450 patients will be enrolled in the trial and split into three treatment groups: one group who will receive the therapy, one group who will receive placebo and a third group who will receive standard medical care. Ability to exercise one year after therapy will be a key indicator of the treatment's effectiveness. Doctors will also collect safety data for two years following the start of the therapy.

The current trial follows on from a phase II study, where the CD34+ stem cell treatment improved exercise capacity and reduced chest pain. 'This is the first time these endpoints have been achieved in a population of patients who have exhausted conventional treatment options', said Dr Douglas Losordo, vice president of new therapeutic development at Baxter.