CSI receives authorization to begin its pivotal trial of ORBIT II

Cardiovascular Systems, Inc. (CSI) (Nasdaq:CSII), has received Food and Drug Administration (FDA) conditional Investigational Device Exemption (IDE) approval to evaluate the safety and effectiveness of its Diamondback 360^® System in the treatment of calcified coronary lesions. With this conditional approval, CSI is authorized to begin its pivotal trial, ORBIT II, in early 2010 and initially enroll up to 100 patients at as many as 50 U.S. sites. Dr. Jeffrey Chambers, an interventional cardiologist with Metropolitan Cardiovascular Consultants, Minneapolis, is the principal investigator for ORBIT II. The Diamondback 360° is a minimally invasive catheter, which received FDA 510(k) marketing clearance in 2007 for the treatment of peripheral arterial disease.

“We have seen the advantages of using the Diamondback 360° in removing calcified coronary plaque prior to using stents or angioplasty”

“The U.S. market for coronary interventions is currently estimated at more than $4 billion, representing 1.3 million procedures each year,” said David L. Martin, president and CEO of Cardiovascular Systems. “A complementary tool to stents and angioplasty, we expect our Diamondback 360° to play a significant role in this market by removing the calcified or fibrocalcific disease to increase the effectiveness of the other therapies. We are optimistic that the success of the Diamondback 360° in treating peripheral arterial disease — as confirmed in our landmark OASIS study and in more than 20,000 patients to date — can be repeated in the treatment of coronary disease.”

In 2008, CSI completed the first in-human ORBIT I coronary trial, a feasibility study which enrolled 50 patients in India. The Diamondback 360° was shown successful in 98 percent of patients, and the acute procedural success rate was 94 percent. These results met the company’s safety and efficacy endpoints and were among the data the FDA considered in granting conditional IDE approval.

“We have seen the advantages of using the Diamondback 360° in removing calcified coronary plaque prior to using stents or angioplasty,” said Dr. Chambers. “In the feasibility study, acute procedural outcomes were positive, and we believe the use of the device also may contribute to improved long-term outcomes in patients with difficult-to-treat disease. We look forward to expanding our understanding of this platform technology for a coronary indication.”

The Diamondback 360° catheter has a diamond-coated crown and unique orbital mechanism of action, ideally suited for removing calcific and fibrocalcific plaque. The coronary platform has been designed for ease-of-use, short procedure times and a minimized risk of complications by using a low-profile catheter, a turbine-powered controller and the proprietary ViperWire™ Guide Wire.

CSI received FDA 510(k) marketing clearance for the Diamondback 360° as a PAD therapy on the basis of data from its OASIS study, the first-ever prospective study evaluating a plaque removal system, which enrolled 124 patients at 20 sites. Acute outcomes demonstrated that the Diamondback 360° device is safe and effective. Six-month results showed no major amputations, and 97.5 percent of patients required no reintervention. Recently announced follow up on 64 patients demonstrated the long-term durability of treatment with the Diamondback 360°, with a 100-percent limb salvage rate maintained and freedom from reintervention in 86.4 percent of patients after two years.