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In a showdown of drug-coated balloons (DCBs) for peripheral artery disease, the investigational Chocolate Touch device came out superior on efficacy in an open-label randomized trial.

Among over 300 patients, the primary efficacy rate of DCB success at 12 months was 78.8% with Chocolate Touch compared with 67.7% with the Lutonix DCB, reported Mehdi Shishehbor, DO, MPH, PhD, of University Hospitals in Cleveland, during the late-breaking clinical trial session at the American College of Cardiology (ACC) meeting in Washington, D.C.

That difference met noninferiority at P<0.0001 and superiority at P=0.04, and was driven by better patency as assessed by duplex ultrasound and lower clinically driven target vessel revascularization.

The primary safety endpoint -- freedom from target limb-related death, major amputation, or reintervention at 12 months -- came out noninferior to the first-generation DCB (88.9% vs 84.6%).

"This is the first head-to head comparison of a first- versus second-generation DCB," the group noted in the paper published simultaneously in .

The Chocolate Touch DCB is designed with a nitinol cage constraining the balloon to form "pillows" that reduce acute vessel trauma and inhibit neointima formation and restenosis through 20% greater surface area that can transfer paclitaxel.

Based on the findings, "perhaps it's going to be a go-to drug-coated balloon for peripheral vascular interventions," said Roxana Mehran, MD, of Mount Sinai School of Medicine in New York City, at an ACC press conference. "Especially in our patients with diabetes and other risk factors where we're seeing higher events rates, I think this is going to be a fantastic addition to the armamentarium of treating patients with peripheral vascular disease."

The included 313 patients with claudication or ischemic pain on rest (Rutherford class 2-4 disease) and superficial femoral or popliteal disease (≥70% stenosis) who were seen at 34 enrolling sites in the U.S., Europe, and New Zealand. Average lesion length was 78.1 mm, and 46.2% of the group had moderate-to-severe calcification. Only 9% of the studied population didn't identify as white.

Participants were randomized to the Chocolate Touch device or the Lutonix device, which at the time of trial design was the most widely used DCB in the U.S.

Despite a rocky course with "interruption of the trial in the United States for 6 months due to the paclitaxel warnings by the FDA and the COVID-19 pandemic," follow-up at 1 year was available for 94% of participants.

No bailout stenting was required and no flow-limiting dissections occurred in either treatment group, which the researchers said was likely due to exclusion of patients with severe dissection after pre-dilatation.

There was also no difference in mortality, with one death in the Chocolate Touch group and two in the Lutonix group at 12 months. However, because the trial started before the paclitaxel safety signal debate started, it was not powered or designed to look at mortality, Shishehbor noted.

A post-hoc analysis of the as-treated population suggested numerically fewer deaths in the Chocolate Touch arm compared with the Lutonix control arm at each time point from 1 to 3 years (P=0.206), although 3-year follow-up was not yet complete.

"However, a post hoc Bayesian predictive analysis indicates an 86.3% posterior probability that the 3-year mortality rates in patients treated with the Chocolate Touch device will be less than the prespecified performance goal of 13.2% derived from a patient-level meta-analysis of U.S. IDE randomized controlled trials," the researchers noted. "A posterior probability of 86.3% supports a similar long-term mortality profile for Chocolate Touch compared with other FDA-approved paclitaxel-coated devices."

Patients are being followed to 5 years.

"Next for the device is going through the FDA [approval] process," said co-author Alexandra Lansky, MD, of Yale University in New Haven, Connecticut. "There are four other DCBs that are approved beyond Lutonix. It certainly puts it in question comparing one DCB to another. In this case we showed superiority to Lutonix. How do these devices compare to other commercially available DCBs?"

Another question is patient selection, she added. "Now we are seeing a device that is more effective than what is out there. Should we be selecting lesions and patient groups that are higher risk: diabetic patients, patients with long lesions, etc? Those would be fair questions to try and address down the road."

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