Medical Device Daily National Editor

CardioMind (Sunnyvale, California), a decidedly under-the-radar developer of coronary stents, has its eye on a specific, underserved sector of the drug-eluting stent (DES) market that it believes can result in growing the worldwide market for the vessel "scaffold" devices.

The company's first-in-human CARE II trial, which has had its start "Down Under" at St. Vincent's Hospital (Melbourne, Australia), is analyzing the use of its Sparrow DES in small, difficult-to-treat blood vessels.

The start of the trial triggered a second-tranche closing of a $33 million venture round raised in June 2007. That round, CardioMind's third since its founding in 2003, included an initial tranche of $11 million for continued R&D and the just-released $22 million for completion of the CARE II study and further development.

Leading the round were SV Life Sciences and De Novo Ventures, with added funding coming from four existing investors.

The cleverly-named Sparrow stent has a .014" crossing profile, some 70% smaller than in diameter than any approved stent currently on the market. Rather than riding to the site of the lesion over the guidewire, as is the case with every other stent, the CardioMind device travels within the guidewire lumen.

It has, as President/CEO Charles Maroney told Medical Device Daily, "a much smaller profile" than other stents on the market.

The mere fact that CardioMind has reported on its new trial activity is news unto itself. It truly is a "stealth" company, an adjective used by media outlets carrying infrequent news about the firm. Only four mentions of the company are found in MDD's archives.

The CARE II trial, which in addition to Australia will enroll patients in Asia, Europe and South America, eventually will enroll 220 patients. The randomized study will compare three different stents bare-metal and DES versions of the Sparrow, plus a competitive stent, the MicroDriver from Medtronic (Minneapolis), characterized by Maroney as that company's "bare-metal, small-vessel stent [which many interventionalists] feel is the best small-diameter stent" on the market today.

He said that the SynBiosys polymer that CardioMind has licensed from SurModics (Eden Prairie, Minnesota) "allows the Sparrow stent to gradually return to a bare-metal state, where we as an industry have 15 years of data showing no increase in late stent thrombosis."

The start of the trial, which thus far has seen 12 patients implanted, has shown "very encouraging results," said Robert Whitbourn, MD, associate professor and director of the Cardiovascular Research Center at the Melbourne hospital. "I am impressed with the overall deliverability and performance of this new delivery system."

He said the Sparrow system "opens up the possibilities of stenting in small vessels, branch vessels and other difficult-to-access vessels."

Whitbourn said such use "could ... expand the types of lesions in coronary artery disease that can be treated in more difficult patient populations."

Maroney told MDD that it is such "difficult" populations diabetics, for example, who tend to have smaller-diameter, more tortuous blood vessels in need of stenting for which CardioMind's stent is particularly of use. 'Our focus is in the smaller vessels. And smaller vessels demand more flexibility, the ability to access in tighter spaces."

The combination, he said, "means that if you want to treat those smaller vessels, you need the most flexible, deliverable system available."

Maroney noted that interventional cardiologists "have been notorious for switching technologies based on deliverability," so that's a potential advantage for us."

In addition, he said, "since we started looking at small vessels and some of the things came to light about durable polymers, that's when we said, 'Hey, if we're going to deliver a drug there, in the end what we want is to have bare struts left,' so that's where we added the biodegradable polymer to the system."

And, Maroney said, "I think the combination of those two aspects makes [the Sparrow] the ideal small-diameter stent."

He said the potential for the small-diameter product can be evidenced in the reality that many interventionalists may be reluctant to treat a patient's small-diameter vessel. "They're reluctant because smaller vessels have poorer results," Maroney said. "So they say, 'Why do I want to put a risk on this patient to treat the smaller vessel? Maybe this is a good candidate for surgery.'"

Asked about the company's timetable for commercialization, he said that the data that will be collected in the CARE II trial will be able to be used in getting the CE mark. "We're using a limus drug, sirolimus, that is generically available," he said, "[but], in the end, we're going to have to have a drug license to commercialize this product in the U..S. and overseas."

That might be, Maroney said, either sirolimus, everolimus, zotarolimus or biolimus, the four limuses that are, in his words, "the most-developed limus drugs at this point." The company won't be trying to offer a new way of treatment with whatever drug is chosen, he said. "Our advantage is that we have a platform specifically designed for those smaller vessels, so we will end up with some sort of an agreement with the holder of one of those drugs, and that's what we will end up commercializing."

The company's expectation, he said, "is that we would end up launching in Europe in 2010."

Maroney said that the data gathered for the European approval "allows you to start your trial in the U.S. [It] would allow us to kick off that trial in even smaller vessels in the U.S. in the normal 2.5 mm to 4.0 mm range, but also in the 2.0 mm to 2.75 mm range, and collect data for those patients as well."

In a company statement, he cited its target of treating blood vessels of smaller than 2.75 mm, which he said "currently constitute nearly 40% of all stent implants."

Maroney added that beyond the range of current stent practice, the CardioMind product "may also find use in vessels smaller than 2.25 mm and thus expand by up to 20% the worldwide market for stents."