HEART RESEARCH
Regenetech has an active program in heart research. Preliminary indications are that Regenetech's expanded adult stem cells can be useful in regeneration of heart tissue. Regenetech is discussing utilization of this technology for clinical trials with several universities with the desire that the expenditures stay in Texas to promote stem cell research in Texas.
Regenetech believes that its broad Intellectual Property position in use of adult stem cells for heart regeneration will make it a dominant entity in heart regeneration therapeutics.
More specifically, Regenetech believes its expanded adult stem cells will replace bone marrow stem cells for heart regeneration. Bone marrow stem cells have been shown to be effective in heart tissue regeneration as outlined in the following press release:
Texas Heart Institute Physicians and Scientists Discuss Advances in Stem Cell Research
HOUSTON (May 7, 2002) Physicians and scientists at the Texas Heart Institute are extending stem cell research from the laboratory to the clinical setting in their ongoing effort to find effective treatments for heart failure and end-stage heart disease. They discussed their activities today in a news conference.
To date, ten patients have received the stem cell treatment developed at the Texas Heart Institute. In a collaborative effort with colleagues in Brazil, four patients in South America initially received the stem cell treatment in December. Another six patients received the treatment in late April. Five patients are in the control group. This is believed to be the largest cardiovascular stem cell study group in the world.
"Clearly this is a work in progress and it's still very early in the process," cautions James T. Willerson, M.D., medical director and director of cardiology research at the Texas Heart Institute, and president of The University of Texas Health Science Center at Houston. "We were fortunate several months ago to have the opportunity to begin this critical next step in the research process. Still, we need larger numbers of patients in both treatment and control groups. Although we are encouraged and optimistic, we have no firm conclusions at this time."
On the basic research level, Dr. Willerson and Yong J. Geng, M.D., Ph.D., the director of the Texas Heart Institute's Heart Failure Laboratory, have been evaluating the treatment using embryonic canine stem cells which develop into cardiovascular stem cells. In the animal model, the research team has found the treatment results in a 30% reduction in scar tissue within the first two weeks.
The goal of the treatment is to replace damaged heart muscle cells and to promote the growth of new blood vessels to supply oxygen to damaged heart muscle. It is Dr. Willerson's long term hope that the stem cells eventually can be used as vectors to deliver new genes which may also assist in the healing of the heart in a dual therapeutic approach.
The stem cells used in the clinical treatment are harvested from the patient's own bone marrow. While doctors say it is not necessarily the best option, there are advantages in that the stem cells are obtained at minimal cost and the patient has no rejection issues. It also keeps the scientists within the regulatory boundaries of stem cell research mandated in the U.S.
"When we harvest the bone marrow, we can select out the population of stem cells that we expect will develop into the physiological structures that we want. We process the bone marrow cells for about three hours and then inject them into the heart," explains Emerson Perin, M.D., director of New Interventional Cardiovascular Technology at the Texas Heart Institute, who is performing the clinical procedures in Brazil.
Finding the best way to deliver the stem cells to damaged hearts is part of the process under investigation. In order to do that, the research team uses the NOGA electromechanical mapping system (Cordis - Miami Lakes, Fl.). Purchased three years ago for diagnostic purposes, the technology was considered too invasive for widespread use. However, the technology is ideal for use in stem cell transplantation.
By entering the body through a tiny incision near the groin, doctors can thread a catheter into the left ventricle, measure electrical and motion capabilities of the heart, and pinpoint damaged or weakened areas of the muscle. The same catheter used to navigate the ventricle can then be used to deliver stem cells to those damaged areas.
"The process is somewhat like a video game. The NOGA gives us a real-time, three-dimensional, color-coded image so we can target the treatment sites within a millimeter of precision," says Dr. Perin.
The doctors use a number of parameters and algorithms to verify placement before they begin the stem cell injections. Although only a tiny quantity is injected into the heart muscle, that injection contains millions of stem cells.
"We expect to publish initial results of the experimental therapy in the next six months. We hope the investigational treatment will become available to patients here by the end of the year," says Dr. Perin.
World-renowned cardiovascular surgeon Denton A. Cooley, MD, founded the Texas Heart Institute in 1962 for the study and treatment of diseases of the heart and blood vessels. Together with the Institute's clinical partner, St. Luke's Episcopal Hospital, it has been ranked among the nation's top ten heart centers in an annual survey published by U.S.News & World Report for the past eleven years.