麻豆传媒

This article is a collaboration between 麻豆传媒 and:

SAN FRANCISCO -- A drug-coated balloon showed durable benefit over standard angioplasty in symptomatic femoropopliteal peripheral artery disease (PAD) in 2-year results from the IN.PACT SFA trial.

The rate of freedom from clinically-driven revascularization or restenosis of the same vessel was 78.9% with the IN.PACT Admiral stent versus 50.1% with percutaneous transluminal angioplasty at that time point (P<0.001).

"There was no late catch-up phenomenon after 1 year," said lead author , of the University of California Davis Vascular Center in Sacramento.

The rate of clinically-driven target lesion revascularization came out 9.1% with the drug-coated balloon versus 28.3% with a standard balloon (P<0.001).

The coated balloon yielded "similar functional status improvement with fewer repeat interventions," Laird reported here at the Transcatheter Cardiovascular Therapeutics (TCT) meeting and simultaneously online in the Journal of the American College of Cardiology.

Durability has been the question, "because there's nothing left behind," , of Saint Luke's Mid America Heart Institute in Kansas City, Mo., told 麻豆传媒. "It was very reassuring to see in the IN.PACT SFA findings that the benefits observed at 1 year were largely sustained without any attenuation over the next year."

A competing device, the Lutonix paclitaxel-coated balloon, showed some late catch-up in restenosis between 1 and 2 years of follow-up in the LEVANT 2 trial, Laird noted at a TCT press conference where the IN.PACT SFA findings were presented.

That difference "highlighted that not all drug-coated balloons are the same," he said, suggesting that their variance in paclitaxel dose on the balloon and excipient molecules used could be an explanation.

Overall, "the strategy of not leaving anything behind is very attractive to interventionalists," Laird said, noting that U.S. practice has been shifting toward drug-coated balloons as an alternative to femoropopliteal stents.

Although the clinically-driven revascularization endpoint may be subject to some bias in an unblinded trial like this, the patency findings put drug-coated balloons on par with that of most stents for lesions of moderate length, , of the Cleveland Clinic, noted in an editorial accompanying the JACC paper.

Choosing the best treatment option in this setting remains the challenge, though, because there's no good data comparing stents against drug-coated balloons for these vessels, he pointed out.

"The decision will undoubtedly rest with the treating physician, taking a personalized approach to each patient, his or her clinical presentation, and lesion characteristics," Shishehbor wrote. "Many factors should be considered: clinical presentation (claudication versus critical limb ischemia), vessel size and lesion length, degree of calcification, post predilatation angiogram, number of runoff vessels, compliance with dual antiplatelet therapy, and cost."

But what is clear is that "plain balloon angioplasty for femoropopliteal lesions appears to be clinically suboptimal and should rarely be performed as a stand-alone treatment," Shishehbor concluded.

The trial, which included 331 patients with symptomatic femoropopliteal lesions up to 18 cm in length causing moderate-to-severe claudication (classified as Rutherford 2 to 4), showed a "low" rate of vessel thrombosis in patients randomized to the study balloon (1.5% versus 3.8%, P=0.243), "with no new events reported between 1 and 2 years."

However, the 2-year overall mortality rate turned up substantially different between groups: 8.1% with the drug-coated balloon versus 0.9% with conventional angioplasty (P=0.008).

At the -- used to support FDA approval granted early in 2015 -- the differential in all-cause death was smaller and not significant: four cases with the drug-coated balloon (1.9%) compared with none with the comparator (P=0.93).

"All of these deaths, as it turns out, were adjudicated by the blinded and independent CEC [clinical events committee] and they found that none of these deaths were device or procedure related. The differences were probably driven by the extremely low mortality in the standard angioplasty arm in this trial," Laird told 麻豆传媒 at the press conference. "If you look through the literature, the usual mortality rates that you would expect in a trial like are typically in the 3% to 11% range."

"The other thing is that the deaths, when they occurred after drug-coated balloon angioplasty, were late," he added. "The mean time to death was 560 days, which is long after the drug is dissipated from the arterial wall. And there were no limb-related deaths in the trial either."

Whereas paclitaxel-eluting stents have consistently lost out to limus-eluting stents, paclitaxel has largely dominated in drug-coatings for PAD balloons, Laird noted.

"The main reason why it's maybe a different scenario," he said, "is that paclitaxel seems to be an ideal drug for a drug-coated balloon because it is very lipophilic and is taken up well into the plaque and vessel wall after just a fairly brief balloon inflation, whereas perhaps with the limus drugs they're not as easily taken up off of the balloon into the vessel wall during the angioplasty procedure."