Cardiovascular Systems (CSI) has received FDA's conditional Investigational Device Exemption (IDE) approval to evaluate the safety and effectiveness of its Diamondback 360 System in the treatment of calcified coronary lesions. The company is likely to begin its pivotal trial, Orbit II, in early 2010.

The Diamondback 360° is a minimally invasive catheter, which received FDA 510(k) marketing clearance in 2007, for the treatment of peripheral arterial disease.

CSI said that with this conditional approval, it is now authorised to begin its pivotal trial, Orbit II, in early 2010 and initially enroll up to 100 patients at as many as 50 US sites.

The company claims that the Diamondback 360° catheter has a diamond-coated crown and new 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 minimised risk of complications by using a low-profile catheter, a turbine-powered controller and the proprietary, ViperWire Guide Wire.

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

CSI has 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.

Additionally, the six-month results showed no major amputations, and 97.5% 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% limb salvage rate maintained and freedom from reintervention in 86.4% of patients after two years.

David Martin, president and CEO of Cardiovascular Systems, said: “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.”