Stent/stent coatings developer MIV Therapeutics (Vancouver, British Columbia) and drug therapeutics firm Endovasc (Montgomery, Texas) last month unveiled plans for a joint venture company, named Stentgenix, which will focus on developing Endovasc's drug Angiogenix for uses in stents. Angiogenix will be developed as a pharmaceutical coating for use in coronary and peripheral stents to block restenosis while at the same time stimulating angiogenesis (new blood vessel growth) in the heart and limbs.

For its part, MIV Therapeutics will continue to push forward with a separate effort to develop a biocompatible coating for standard stents. Company president Alan Lindsey touted this new coating as "very well becoming the coating of choice for the entire [stent] industry." He characterized the coating, called hydroxyapatite (HAP), as "a material that we basically manufacture but [that] assimilates the same material as in your bones and your teeth."

Endovasc's contribution to the Stentgenix R&D effort will be on the drug side, via Angiogenix, a drug it describes as having potential as "the first angiogenic agent." One of the strategies for the products to be developed by Stentgenix will be a stent that slowly delivers Angiogenix to the feeding artery that leads to the ischemic area, stimulating the growth of new blood vessels and creating a potential biological alternative to invasive procedures. Endovasc said it would sub-license its "field of use" rights for the Angiogenix drug technology and license its biodegradable/resorbable stent and catheter technologies to Stentgenix.

While Stentgenix will be one of the smaller players in this market, carving out any portion of that space offers large opportunities. With coated cardiovascular stents coming online next year, the stent market has been projected to grow from somewhat more than $2 billion annually to up to $6 billion by 2008. MIV, formerly DBS Holdings and renamed earlier this year, has a dual focus: first on new stent systems and secondly on biocompatible coating for them. Lindsay has projected commercialization of its bare stent technology in the first quarter of next year and clinical trials of a stent coated with its proprietary ceramic material later in the year. The material is licensed and being co-developed with the University of British Columbia (also Vancouver), with Lindsay saying that the university is in the process of "transferring the technology over to our facility" for MIV to provide fine-tuning of the stent/coating combination.

Lindsay noted that polymers and other stent coatings have the basic disadvantage of cracking when a stent is placed in the body and changing shape during placement or afterward, allowing debris to leach into the circulatory system. By comparison, he said that MIV's material has been engineered to be so fine that it is "invisible to the naked eye" and so thinly coated on the stent that there is no cracking. "It basically protects the arteries or vessels from being exposed to metal," he said.

MIV also previously developed licensing agreements with Endovasc for the manufacturing and marketing of Endovasc's PROStent drug-eluting stent. In the new joint venture, MIV will contribute its stainless steel stents while also providing initial funding of $2.5 million for the new company.

In its statement reporting the new venture, Endovasc said that the approaches that Stentgenix will focus on "could enable interventional cardiologists, interventional radiologists and vascular surgeons trained in catheter procedures anywhere in the world to use the new therapy for many forms of heart and vascular disease in conjunction with common angioplasty procedures."

Angiogenix is a small molecule derived from the tobacco plant that, when given in low doses, has demonstrated new muscle growth in four different animal experiments with simulated blood-flow deficiencies, suggesting that it will do the same in a human patient's heart and limbs, according to Endovasc. Thus, the company is focused on exploring Angiogenix in various cardiovascular applications, including use for the relief of angina via restoration of blood flow to ischemic areas of the heart, to stave off heart attacks, and other more advanced coronary conditions.

David Summers, chairman and CEO of Endovasc, predicted that the applications for Angiogenix therapy could be increased "literally thousandfold, as angioplasty can be performed all over the world, even in small remote hospital settings."

Another pending phase III product being developed by Endovasc is Liprostin, a naturally occurring liposomal prostaglandin-based treatment that studies suggest will prevent restenosis (re-blockage of arteries), increase circulation and reduce leg pain due to poor blood flow.

Centerpulse exits vascular sector

Centerpulse (Zurich, Switzerland) said last month that it had closed the sale of its Vascutek Ltd. (Glasgow, Scotland) unit to Terumo (Toyko), which completes its exit from the vascular devices market sector. The $170 million deal was announced in early October. Vascutek, which was acquired by Centerpulse's predecessor, Sulzer Medica, in 1990, is a maker of vascular prosthetic grafts for treating diseased and damaged arteries. Its knitted and woven polyester grafts are produced in both sealed and unsealed versions. Vascutek's U.S. plant is located in Austin, Texas.

Centerpulse sold its IntraTherapeutics unit (St. Paul, Minnesota) earlier in November to ev3, a portfolio company of the private equity firms Warburg Pincus and The Vertical Group, for about $95 million. IntraTherapeutics is a maker of balloon-expandable, non-coil stents and self-expandable coil and non-coil stents for use in peripheral arteries.

Centerpulse said proceeds from the two divestitures would be used to redeem parts of the credit facility that it used to finance the company's $750 million hip and knee implant settlement in the U.S. It added that the sale process for the company's cardiac division continues to proceed "according to plan," and was expected to close by year-end or early in 2003. Centerpulse is divesting those businesses in order to focus its strategic emphasis on the core sectors of orthopedic, spine and dental implants.

da Vinci system gets mitral valve OK

A robotic surgical system already approved for general surgery is venturing into uncharted territory. FDA approval last month clears the way for hospitals to use the da Vinci Surgical System from Intuitive Surgical (Sunnyvale, California) for minimally invasive mitral valve repair procedures, also described as "closed chest."

"The approval for a cardiac procedure means we will immediately begin pursuing approval for other cardiac procedures, such as atrial septal defects," Lynn Thompson, director of investor and media relations, told Cardiovascular Device Update. Intuitive's system already is approved for general laparoscopic, thoracoscopic and radical prostectomy.

The da Vinci is not cleared for coronary artery bypass graft (CABG) procedures, but that is another application target for Intuitive. "The first patient in the clinical trial [for CABG] was operated on in January of this year," Thompson said. "The trial is progressing quite well, and we expect it to last through 2003. That's our goal, at least."

Patient satisfaction to use of the da Vinci system was positive at Columbia Presbyterian Hospital (New York), said Michael Argenziano, MD, assistant professor of surgery and director of cardiac robotic surgery at Columbia University (New York). "We've performed nearly 100 cardiac surgery cases using the da Vinci system. When using robotics in mitral valve surgery, our post-surgery survey results show an overall increase in patient satisfaction."