CorMatrix Cardiovascular (Marietta, Georgia) reported an additional indication from FDA for its Extracellular Matrix technology (ECM). The company's platform ECM technology is described as an extracellular matrix biomaterial that provides a natural bioscaffold that enables a patient's own host cells to repopulate and repair otherwise damaged tissues.

"When we talk about our technology to cardiologists and [describe] how it works, we like to use the example of an acorn," Beecher Lewis, CorMatrix's president and COO, told Medical Device Daily. "You can take one acorn and put it on your desk and it won't grow into an oak tree. You can put a thousand acorns on your desk and still nothing will happen. But if you put that acorn in rich soil then it's going to grow into a tree because then it's in the right environment. That's what ECM is for damaged tissue it provides the right environment for that tissue to grow and repair itself."

The initial FDA clearance, which came in August 2005, is for the reconstruction and repair of the pericardium during cardiac surgery. It received CE Mark shortly after. To date, this application has been implanted during in excess of 4,000 cardiac procedures at more than 160 U.S. hospitals, according to the company.

ECM was developed in the 1990s by Purdue University (West Lafayette, Indiana).

The additional indication expands the use of the implant to include suture-line reinforcing, buttressing for soft tissue reaproximation, repair of cannulation sites and bleeding sites, and as an intracardiac patch or pledget for tissue repair of structural problems such as septal defects.

Here's how the application works.

Following implantation through a suture tissue adjacent to the site, the ECM matrix delivers cells and nutrients, and the matrix itself recruits marrow-derived cells from the periphery which can then differentiate into tissue-specific cells. The cells rapidly enter the ECM material. Blood vessel remodeling follows, allowing more nutrients and cells to enter the matrix.

The ECM is gradually replaced as the patient's own body reinforces and rebuilds the weakened site. The body's tissue begins remodeling into the surgical site while the ECM maintains the needed tissue support.

The CorMatrix ECM is made from small intestinal submucosa derived from pig jejunum the central part of the small intestines. The ECM on the surface looks like a sheet of collagen and measures about 7 cm by 10 cm.

To transform this naturally-occurring material, the cells are removed, the threat of endogenous viruses is eliminated using an oxidative process, and the material is terminally sterilized using ethylene oxide gas.

When implanted, the ECM acts as a scaffold into which the patient's cells migrate and integrate, stimulating the patient's natural wound-healing mechanisms. As the patient's cells become active, they secrete collagen, which then matures over time to form a strong and permanent tissue repair. Because the ECM contains primarily collagen, the graft is gradually replaced as the patient's tissue gradually turns over in a natural state of self-renewal.

CorMatrix isn't the only company to use extra cellular biomatrix materials.

Depuy Spine (Raynham, Massachusetts) a Johnson & Johnson (New Brunswick, New Jersey) company, and Cook Biotech (West Lafayette, Indiana) hold patents and have developed applications using the technology. The only difference is, CorMatrix's applications are primarily for the cardiovascular market.

"The FDA was pretty familiar with ECM because of previous [offerings] from Cook and Depuy," Lewis said.

In fact Cook and CorMatrix established a cross-license agreement to help with the development of certain cardiovascular medical devices using proprietary extracellular biomaterials held by each company (Medical Device Daily, March 1, 2005).

"That agreement is still ongoing," Lewis told MDD.

CorMatrix, which was established in 2001, is a private company and also somewhat of an "anomaly," according to Lewis.

"We have no VC money or corporate partners which gives us a chance to look into markets that might not be that large but offer opportunities for us to take our technologies into," he said, while declining to go into further detail about the company's financings or market capitalization.

Among its future offerings, CorMatrix is working toward an injectable form of ECM. Evidence supporting this application was presented at the American College of Cardiology (ACC; Washington) scientific sessions in Chicago in early April.

The data involved ECM technology in the form of an injectable emulsion, enhanced angiogenesis, increased recruitment of C-kit positive progenitor stem cells, and improved cardiac function in a rat model.

The study, conducted at Emory University (Atlanta), used rats that were subjected to 45 minutes of coronary occlusion, followed by an injection of either the ECM Technology emulsion or a saline control into the affected myocardium and examined at three, seven, 21 and 42 days.

"This data demonstrates the unique potential of the extracellular matrix material in cardiac applications," Lewis said. "We are very excited about the results of this study and will continue to evaluate the broad potential utility of our patented ECM technology."

Although there is no immediate plan for release of the injectable form of ECM, he said that this would be a "huge advancement" for tissue repair when launched.