Medical Device Daily Associate

A new twist on the ever-popular drug-eluting stent (DES) is being developed in the field of coronary artery bypass grafts by a familiar face and an interesting newcomer.

The old timer in this case is Angiotech Pharmaceuticals (Vancouver, British Columbia), whose paclitaxel compound – a cancer drug that has anti-inflammatory properties – already is used by Boston Scientific (Natick, Massachusetts) on its wildly successful Taxus DES system to inhibit restensosis in the treatment of coronary artery disease.

CABG Medical (Minneapolis) is the newcomer who is partnering with Angiotech, via an exclusive license agreement, to extend paclitaxel technology into coronary by-pass surgery, specifically as a coating on the vascular connectors on its only product, the Holly Graft system.

In connection with the license agreement, Angiotech will receive a warrant to purchase 1,262,823 shares of CABG Medical's common stock, exercisable at 1 cent per share. Angiotech also will be entitled to milestone payments upon the achievement of identified clinical development objectives and in addition will receive royalties on sales of the system.

In a separate transaction, Angiotech also has agreed to purchase up to $10 million of CABG Medical's common stock at a 15% premium to its market value, with a current investment of $5 million and an additional $5 million investment upon CABG Medical's achievement of certain revenue milestones.

The companies noted that despite the success of coronary stenting, more than 600,000 patients worldwide have coronary artery bypass procedures requiring an average of three bypass vessels per procedure. Roughly 20% of these patients experience some type of complication as a result of a traditional vessel harvesting for a typical bypass procedure.

According to Todd Young, vice president of investor relations and communications at Angiotech, this latest use of paclitaxel allows the company to hand off the technology to another company. "It's something we want to get in the habit of doing," he told Medical Device Daily. "It's spreading our IP around and spreading our licenses around and finding interesting companies with interesting technologies that can benefit from local drug delivery and then letting them do all the local R&D."

William Hunter, MD, president and CEO of Angiotech, said, "We are excited to have the opportunity to extend our novel drug-eluting technology into the coronary bypass field through our new relationship with CABG Medical."

Echoing Young's sentiments, Hunter also noted that the company is "pleased to continue to recognize value from our extensive intellectual property portfolio and know-how in the area of local delivery of paclitaxel – we expect that many more partners will seek access to our proprietary position through licenses to our technology, which is covered by many valid and issued patents throughout the world."

CABG Medical's Holly Graft system is designed to eliminate the need during a bypass procedure to perform a second surgery to harvest vessels from the chest, legs or arms for use in the coronary artery bypass procedure. The company believes the system may potentially reduce operating-room time as well as post-operative care and readmissions.

The system may be used in procedures that incorporate either the heart-lung bypass machine or in so-called "off-pump" procedures giving surgeons added flexibility.

Holly Graft consists of a thin-walled and flexible vascular graft made of expanded polytetrafluoroethylene (ePTFE). The ePTFE graft is attached to coronary arteries using one or more vessel connectors and a titanium flow limiter to control flow and pressure. The connector and the limiter are attached to the ePTFE graft and the arteries using standard suture material.

Working together, these elements allow blood to flow into the system at the aorta, where blood pressure is relatively high, and out of the system at the superior vena cava or pulmonary artery, where blood pressure is relatively low. In between, blood will bypass diseased arteries and flow into one or more healthy coronary arteries through vessel connections established by surgeons.

The vessel connector will use a drug combination that includes paclitaxel, which has been specifically designed to reduce the risk of blockage and tissue formation.

Interestingly, CABG Medical, which closed on a $27.8 million IPO in December (MDD, Dec. 15, 2004), had come to the conclusion that paclitaxel was a necessary component to the success of the Holly Graft, according to CABG Medical President and CFO John Babbit. Indeed, the company had already been using the drug in its clinical trials.

He said that in light of the success of the paclitaxel in preclinical work, the company had not wanted to go forward to clinical studies without the drug.

"We've seen the results in our work that we've done with paclitaxel already," Babbit told MDD. "We've been working with paclitaxel for about 18 months and we just hadn't come to terms on a licensing agreement [with Angiotech]." He added that last week, the two companies were able to finally sit down and form a collaboration "that we felt worked for both sides."

Noted med-tech inventor and entrepreneur Manny Villafana, who is the chairman and CEO of CABG Medical, also acknowledged the significance of the licensing agreement. "We are proud to have taken our next big step forward in developing the Holly Graft system by establishing a relationship with the technology leader in drug-device combinations."

He added: "In addition to securing access to the technology and know-how of Angiotech, through our license agreement we have secured the intellectual property foundation underlying the paclitaxel franchise, which we feel significantly enhances our competitive and proprietary position."

The only other company known to be actively attempting to develop a synthetic CABG product is CardioTech International (Woburn, Massachusetts), whose CardioPass system is currently in clinical trials and is expected to receive both a CE mark and FDA approval within the next couple of years.