DEFINITIVE LE Supports Directional Atherectomy With Covidien's TurboHawk and SilverHawk

August 18, 2014—Covidien announced the publication of the DEFINITIVE LE study results demonstrating that directional atherectomy using the company’s TurboHawk and/or SilverHawk system is safe and effective as a frontline therapy for the treatment of peripheral arterial disease (PAD). DEFINITIVE LE Co-Global Principal Investigator James F. McKinsey, MD, et al published the data in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions  (2014;7:923–933).
 
According to Covidien, DEFINITIVE LE (Determination of Effectiveness of SilverHawk/TurboHawk Peripheral Plaque Excision Systems for the Treatment of Infrainguinal Vessels/Lower Extremities) demonstrated 95% limb salvage in patients with critical limb ischemia (CLI) and 78% overall patency in claudicant patients at 12 months. The TurboHawk and SilverHawk devices are catheter-based, minimally invasive treatments that remove plaque and restore blood flow without leaving anything behind in patients with PAD.
 
In the company’s press release, Dr. McKinsey commented, “The DEFINITIVE LE study provides confirmatory evidence based on 12-month, independent, core lab–adjudicated data on the use of directional atherectomy in treating a diverse, real-world group of patients with PAD.” He added, “The study enrolled 800 patients, making it the largest trial with independent core lab analysis for atherectomy to date. Results of the study demonstrate high limb salvage and patency rates and diabetic outcomes. This further confirms the effectiveness and versatility of directional atherectomy in a wide range of vessel sizes and clinical presentations. Atherectomy is an important treatment option, as the therapy leaves nothing behind in the body and preserves all future treatment options.”
 
As summarized by Covidien, the prospective, multicenter DEFINITIVE LE study enrolled 800 patients in 47 centers in United States and Europe and included two patient cohorts: those with claudication and those with CLI. Patients enrolled in the study were treated with the TurboHawk and/or SilverHawk. The company noted that for the first time in an atherectomy study, DEFINITIVE LE also included a prespecified subgroup analysis comparing patency rates in diabetic and nondiabetic patients. 
 
Among patients with claudication, primary patency was 78% (95% confidence interval [CI], 74%–80.6%) at 12 months. This rate did not differ between patients with diabetes versus those without diabetes (77% vs 78%; noninferior, P < .001)—the first such results to be shown in a prospective, powered analysis, the company stated. Specifically for the superficial femoral artery, the patency rates were 83% in lesions < 10 cm in the claudicant cohort.
 
Additional data summarized in JACC: Cardiovascular Interventions include the following: a 95% rate of freedom from major unplanned amputation of the target limb at 12 months in CLI patients (95% CI, 90.7%–97.4%); periprocedural adverse events including embolization (3.8%), perforation (5.3%), and abrupt closure (2%); and a bailout stent rate of 3.2%.
 
Also in Covidien’s announcement, DEFINITIVE LE Co-Global Principal Investigator Lawrence A. Garcia, MD, commented, “The outcomes for patients with claudication reveal that, in the scientific landscape, directional atherectomy is not only safe but effective to a similar degree as previous trials in the superficial femoral artery. Diabetic patients, who remain challenging for therapy due to their advanced and multilevel disease, have similar patency rates to nondiabetic patients with claudication when performing directional atherectomy. These findings provide strong clinical support for the versatility of directional atherectomy in treating patients with diabetes, claudication, and CLI.”
 
In October 2012, Dr. Garcia first presented the 12-month data from DEFINITIVE LE at the VIVA: Vascular InterVentional Advances meeting in Las Vegas, Nevada, during a VIVA late-breaking trials session.
 
Covidien noted that DEFINITIVE LE is the largest of three DEFINITIVE studies in a series that also includes DEFINITIVE Ca++ and DEFINITIVE AR. The DEFINITIVE series enrolled 1,054 patients in the United States and Europe to evaluate the effectiveness of directional atherectomy.