Presentation reviews trial design, potential implications of LIBERTY-360, ENDOMAX

SAN FRANCISCO — The LIBERTY-360 and ENDOMAX trials have the potential to provide novel, much-needed data on the use of available endovascular tools for treating outflow disease, particularly critical limb ischemia, according to a presentation at the TCT Scientific Symposium.

“The rise in revascularization and endovascular therapy began, in the U.S. at least, around 2001 and 2002. We really saw an exponential increase, and those trends continue today,” Herbert D. Aronow, MD, MPH, director of interventional cardiology and cardiac catheterization labs at the Rhode Island & the Miriam Hospitals, said during a presentation. “Despite the increased use, however, we have very few comparative effectiveness data to support the use of available endovascular tools for treating outflow disease and, in particular, for treating [critical limb ischemia].”

LIBERTY-360

Aronow reviewed the background, study design and primary and secondary endpoints of LIBERTY-360, as well as anticipated enrollment, which is expected to be completed in March.

“LIBERTY-360 is a [peripheral artery disease] registry,” he said during his presentation.

The prospective, observational, multicenter study evaluates endovascular device interventions for treating lower-extremity PAD, including intermittent claudication and/or critical limb ischemia (CLI). Short- and long-term clinical and economic outcomes are being evaluated and are the primary objectives of the trial, according to Aronow. Secondary endpoints include procedural and lesion success and major adverse events, as well as several others.

“To date — that is as of earlier this month — 1,080 of 1,200 subjects were enrolled,” Aronow said, including nearly 440 of the 500 patients with claudication, more than 550 of the 600 patients with a Rutherford classification of 4 and 5, and nearly 90 of the 100 patients with a Rutherford classification of 6. “The trial is well on its way.”

ENDOMAX

The ENDOMAX trial aims to determine whether bleeding risk can be reduced in patients undergoing an endovascular procedure, including carotid artery stenting, peripheral vascular intervention for claudication or CLI when patients are treated with bivalirudin (Angiomax, The Medicines Company) vs. heparin. Bleeding is the most common complication after peripheral vascular intervention, according to Aronow.

“We have randomized data in [the] coronary realm, as you know, looking at bivalirudin vs. heparin, but we don’t have it when it comes to lower-extremity PAD, not on a large scale,” he said. “The rationale here is to look at transfemoral endovascular intervention, specifically carotid artery stenting and lower-extremity peripheral vascular intervention for patients with claudication or CLI.”

The Bleeding Academic Research Consortium (BARC) definitions for bleeding also were reviewed. BARC bleeding of at least 3 at 48 hours after a procedure is the primary endpoint of the ENDOMAX trial, according to Aronow.

“ENDOMAX will be important in that we’ll finally have some definitive information regarding relative effectiveness of the safety of [bivalirudin] vs. unfractionated heparin in the setting of endovascular procedures,” he said. “Until now, we’ve largely relied on data from the coronary realm.”

Implications

Because LIBERTY-360 and ENDOMAX are in progress, Aronow described his presentation as a description of “the rationale for — and the design of” both trials.

“Whether the tools we have at our disposal can be tailored to patient demographic, patient anatomic or patient lesion characteristics, is unknown,” he said.

According to Aronow, both trials will provide practicing clinicians with “important data on the relative cost-effectiveness of these strategies in the setting of carotid stenting and lower extremity peripheral vascular intervention for CLI.” – by Julia Ernst, MS

Reference:

Aronow HD. Session III. Lower-Extremity Intervention: SFA and Popliteal, Part 3. Presented at: TCT Scientific Symposium; Oct. 11-15, 2015; San Francisco.

Disclosure: Aronow reports that he or his spouse has served as a noncompensated member of an executive committee for ENDOMAX (the Medicines Company).