Privately held Sunrise, Fla.-based Bioheart Inc. recently closed its Series D round, in which it raised $19 million, about $4 million more than expected.

The private placement was oversubscribed due to additional investor interest, said Howard Leonhardt, Bioheart's president and CEO, adding that the financing "actually could have been greater than that amount, but we had a time cutoff."

To date, the company has raised about $55 million. Proceeds are expected to sustain operations through 2006 and fund upcoming Phase II/III trials for the company's autologous cell products aimed at repairing damaged heart muscle. Leonhardt said money also will go toward expanding the company's research and development laboratories in Florida and continued work on other pipeline products, such as a biological pacemaker.

"Our intention is to leverage our position to become a leading cardiology company, along the lines of Guidant, Medtronic or Boston Scientific," Leonhardt told BioWorld Today,

Bioheart's lead product, MyoCell, is a composition of myogenic cells, also known as muscle stem cells, that are taken from a patient's thigh muscle and grown in culture for about two to three weeks. Then, using the MyoCath catheter device, the cells are delivered to the damaged portion of the heart muscle, where it takes about three months to take hold and multiply.

But the MyoCell composition "is much more than just processed cells," Leonhardt said. "We don't want raw pluripotent stem cells, which can become anything," including the fibroblast makeup of scar tissue. And cells that have committed to become thigh muscle cells are equally as useless.

"What we use is a special cell population," he said, estimating that out of a billion cells, about 30,000 might be found that can comprise the MyoCell product. "We have very narrow, special criteria. They have to be one step up from stem cells, but one step below thigh muscle cells.

"Once we extract those out, we give them the right type of food to make them grow to 800 million," Leonhardt added. "We suspend them in a special gelatin solution that holds nutrients, and is full of factors that orient the cells to the cardiac phenotype."

The MyoCell and MyoCath products, which are being developed to work in combination, are aimed at providing an alternative to heart transplants, heart failure drugs, pacemakers and implanted metal and plastic pumps.

Development on the products is about a year closer to regulatory approval in Europe. Leonhardt said a "conservative timeline" for European approval is the first quarter of 2007, with potential U.S. approval during the first quarter of 2008.

Following those products by about two years will be Bioheart's biological pacemaker. That product also relies on autologous cells, this time from the patient's own heart. Since a small number of pacing cells are needed to regulate the heart, only a few healthy cells are needed. Once those are cultured in the lab, they can be administered via the MyoCath catheter.

The company also has plans to develop a biventricular pacemaker that would be designed to enhance biogenesis and angiogenesis. It also is working on second-generation MyoCell products.

Investors in the Series D round were: Advent-Morro Equity Partners, of Puerto Rico; the Astri Group, of Miami; the Magellan Group; Presidential Capital Partners, of Miami; Dan Marino Investments; Minnesota Biomed Partners; and New World Angels, of Boca Raton, Fla.

Individual investors were William Murphy, founder of Cordis Corp., a unit of Johnson & Johnson, and David Gury, former chairman and CEO of Boca Raton, Fla.-based Nabi Biopharmaceuticals Inc.