Final 3-Year ORBIT II Data Presented for CSI's Diamondback 360 OAS

May 5, 2016—Cardiovascular Systems, Inc. (CSI) announced that the final 3-year results from its pivotal ORBIT II study were presented at the Society for Cardiovascular Angiography and Interventions (SCAI) 2016 scientific symposium in Orlando, Florida.

The ORBIT II study evaluated the safety and efficacy of the company’s Diamondback 360 coronary orbital atherectomy system (OAS) classic crown in treating patients with de novo severely calcified coronary lesions. 

The data were presented by Jeffrey Chambers, MD, of Metropolitan Heart and Vascular Institute, Mercy Hospital, in Minneapolis, Minnesota. In the company’s press release, Dr. Chambers commented, “Using the coronary OAS to treat calcium prior to stent implantation delivers procedural success and durable long-term outcomes in these complex patients with severely calcified coronary lesions.”

At 3 years, ORBIT II showed a major adverse cardiac event (MACE) rate of 23.5%; a myocardial infarction (MI) rate of 11.2% (non–Q-wave MI = 10%; Q-wave MI = 1.2%); a target vessel revascularization/target lesion revascularization (TVR/TLR) rate of 10.25%; a TLR rate of 7.8%; and a cardiac death rate of 6.7%. 

The Kaplan-Meier method was used to estimate 30-day to 3-year event rates. Certain 1- and 2-year rates were updated at 3-year data extract.

At in-hospital, 30 days, 1 year, and 2 years, respectively, results were:

• MACE rate: 9.8%, 10.4%, 16.9%, and 20%
• MI rate: 9.3%, 9.7%, 10.6%, and 10.9%
• Non–Q-wave and Q-wave MI rates: 8.6% and 0.7%, 8.8% and .9%, 9.7% and 0.9%, and 10% and 0.9%
• TVR/TLR rate: 0.7%, 1.4%, 5.8%, and 8.1%
• TLR rate: in-hospital rate not reported, 0.7%, 4.7%, and 6.2%
• Cardiac death rate: 0.2%, 0.2%, 3.2%, and 4.7%

Also at SCAI, Dr. Chambers presented the results of an ORBIT II gender subanalysis. Recent publications have indicated that women are an understudied population in clinical studies evaluating percutaneous coronary intervention. Dr. Chambers concluded, “In the ORBIT II trial, similar rates of MACE through 3-years postprocedure exist in both males and females. This is significant, and an example of CSI’s thoroughness when conducting clinical studies.”

CSI received US Food and Drug Administration (FDA) approval for the use of the Diamondback 360 OAS in coronary arteries in October 2013. The device received FDA 510(k) clearance for use in peripheral arteries in August 2007.