Bioheart launches trial of genetically modified muscle stem cells for heart repair

2 April 2010

Florida based Bioheart, Inc., (BHRT.OB) has commenced work on its REGEN trial, a Phase I clinical trial to test genetically modified muscle stem cells in hearts of patients suffering from congestive heart failure (CHF).

Bioheart’s MyoCell is a regenerative cell therapy that uses myoblasts, or muscle stem cells, that are grown from a patient’s own muscle. MyoCell has been tested successfully on patients in four clinical trials.

The REGEN trial is designed to test the safety and effectiveness of a composition of muscle stem cells that have been gene-modified to induce a greater than usual release of the SDF-1 protein. The SDF-1 protein is a molecule in the human body that, after an injury, is naturally released by most tissues to attract stem cells. The stem cells assist with the healing process.

Unlike other tissues, the heart muscle does not release enough SDF-1 to attract the number of stem cells that would result in complete self-healing. As a result, scar tissue forms and impairs normal heart function.

Results from Bioheart’s preclinical animal studies have shown that the genetically modified MyoCell is far more effective than MyoCell alone in accomplishing repair and tissue regeneration. With SDF-1, there is a release of additional therapeutic proteins to assist in the tissue repair process, resulting in a more expansive and quicker repair. Once that repair or regeneration has occurred, the patient’s improved heart function permits the patient to return to a normal life style.

Karl Groth, Bioheart’s Chairman and Chief Executive Officer said, “We are extremely proud and excited to be able to commence our REGEN clinical trial: the first and only FDA-approved clinical study evaluating the therapeutic benefit of combined modified gene/cell therapy for CHF. 

"Bioheart's pre-clinical results using this therapy have demonstrated that our combined gene/cell therapy should significantly enhance the clinical improvements we have already observed in our Phase II/III MyoCell study. As the leader in regenerative medicine, Bioheart, through its REGEN trial, takes the first step toward making available a solution for the treatment of heart failure, the most rapidly growing of all cardiovascular disorders.

According to statistics provided by the American Heart Association, in the US, approximately $22.5 billion are the direct and indirect annual costs of heart failure treatment. To bring effective, safe and cost effective clinical treatments to those with congestive heart failure is our mission.”

The treatment with MyoCell involves taking a biopsy from the patient’s leg muscle, transporting that biopsy to Bioheart’s cell manufacturing facility, expanding the number of cells from the biopsy, and inducing the cells to regress to produce precursors to muscle cells called myoblasts. These cells know that they are muscle cells, but do not know which muscle.

Once those precursor cells, or myoblasts, are present, they are segregated from the muscle cells and grown until they number over 1 billion cells. The myoblasts are then transported back to the patient’s treatment centre. Some are then injected into the patient’s heart with a needle tipped injection catheter.

The treatment used in the REGEN trial involves genetically modifying myoblasts, utilizing Bioheart’s proprietary process. The modified cells are injected in the same manner into the patient’s heart. The modified myoblasts are created using an adenovirus vector or non-viral vector. The myoblasts will release increased levels of the SDF-1 protein, which stimulates angiogenesis and regeneration of tissue.

A heart attack limits adequate blood flow to the heart. In response, the body naturally increases the level of SDF-1 protein in the heart but not enough to heal the damaged tissue. By modifying the myoblasts to express additional SDF-1, the SDF-1 protein levels present in the heart are multiplied exponentially.

The additional quantities of SDF-1 protein stimulate the recruitment of the patient’s existing stem cells to the cell transplanted area. The recruited stem cells will assist in the tissue repair and blood vessel formation process. Preclinical animal studies showed a 54% improvement of heart function when the myoblasts were modified to increase SDF-1 protein prior to injection of myoblasts as compared to 27 percent for the animals treated using myoblasts without modification.The animals treated with a placebo showed a decline in function of 10%.

Howard Leonhardt, Bioheart’s Chief Scientific and Technology Officer, who led Bioheart during the period when the genetically modified myoblasts were being developed and tested said: "Seven years of intense preclinical development, sponsored substantially by Bioheart, at The Cleveland Clinic with Dr Marc Penn and the University of Florida with Dr Barry Byrne and Dr Carl Pepine led to this landmark clinical study."

After completing the REGEN trial, the company plans to transition this second-generation product into its FDA approved Phase II/III MARVEL study. Bioheart plans to further study the modified myoblasts by treating a set of patients who are participating in the study and observing the differences in clinical and heart function among the modified group, those who are treated with MyoCell alone, and a placebo group.