Even at 2 Years, Paclitaxel-Coated Balloon Bests Standard Balloon in Fem-Pop Lesions: IN.PACT SFA

October 27, 2015

SAN FRANCISCO, CA — Superior femoropopliteal artery (SFA) patency seen at 1 year with a drug-coated balloon (DCB) held firm at the 2-year follow-up in a large international randomized trial that compared the IN.PACT Admiral (Medtronic) paclitaxel-delivering balloon and a standard percutaneous transluminal angioplasty (PTA) balloon in patients with symptomatic SFA or proximal popliteal artery disease[1].

The "excellent and durable" results of the IN.PACT SFA trial, which were consistent across "all important subgroups" in a post hoc analysis, "will drive a paradigm shift with regard to SFA interventions," Dr John R Laird (University of California Davis Medical Center, Sacramento) contended when describing the trial at a briefing for the media here at TCT 2015.

Other paclitaxel-eluting DCBs explored in femoropopliteal-artery disease have produced less consistent outcomes, especially after 1 year, as previously covered by heartwire from Medscape. In his presentation to reporters and at the trial's formal presentation at TCT 2015, Laird emphasized that "not all drug-coated balloons are the same," even among those that elute paclitaxel. They differ in drug doses, elution dynamics, mechanical structure, and other factors, so the current study's results in the periphery aren't necessarily generalizable to other DCBs, he said.

IN.PACT SFA had randomized symptomatic patients with SFA lesions to undergo revascularization and be followed for up to 5 years, 220 to be treated with the paclitaxel balloon and 111 a standard angioplasty balloon. As previously published, outcomes at 1 year had shown a significant advantage for the DCB for the primary patency end point of freedom from clinically driven target lesion revascularization (CD-TLR) or freedom from restenosis (82.2% vs 52.4%, P<0.001) by duplex ultrasound[2]. CD-TLR on its own also was superior in the DCB arm (2.4% vs 20.6%, P<0.001) compared with the PTA arm.

Outcomes at 2 years, reported at the sessions and published about the same time in the Journal of the American College of Cardiology with Laird as lead author, showed the numbers for both groups sliding a bit but remaining significantly and sharply different in favor of the DCB for most end points.

24-Month Outcomes, Drug-Coated Balloon (DCB) vs Balloon Angioplasty (PTA) In Symptomatic Femoropopliteal Artery Disease

Outcomes at 24 Months DCB, n=220 PTA, n=111 P
Primary efficacy outcome 78.9 50.1 <0.001
Clinically-driven TLR 9.1 28.3 <0.001
All TLR 10.1 29.2 <0.001
Primary safety outcome 87.4 69.8 <0.001
Major adverse events 19.2 31.1 0.023
All-cause mortality 8.1 0.9 0.008
Clinically driven TVR 12.6 30.2 <0.001
TLR=Target-lesion revascularization
Primary efficacy outcome=Patency as defined by freedom from clinically driven TLR or freedom from restenosis (by duplex ultrasound)
TVR=Target-vessel revascularization
Primary safety outcome=Freedom from 30-day device and procedure-related death and target limb major amputation and clinically driven TVR within 24 months

The post hoc analysis showed a consistent advantage for the primary patency end point with the DCB across patient and anatomic subgroups. In particular, DCB was superior among diabetics (73.3% vs 45.8% for regular balloon, P<0.001) and women (76.7% vs 42.3%, respectively, P<0.001), two groups about which there had been questions regarding DCB relative efficacy.

One safety end point lagged for DCB: all-cause mortality, which in the 24-month analysis was 8.1% compared to 0.9% for the standard balloon (P=0.008); there was no such significant contrast in the 1-year analysis.

"All of these deaths were adjudicated by the blinded and independent clinical events committee, and they found that none of them were device- or procedure-related," Laird said at the press conference.

"The differences were probably driven by the extremely low mortality rate in the standard-angioplasty arm of this trial," he said, noting that the expected mortality based on the literature would have been "in the 3%-to-11% range." There were no limb-related causes of death; rather, the deaths were generally from causes like cardiac disease, infections, or malignancies, "clearly nothing that we could tie to or relate to the procedure."

Also speaking at the press conference, Dr Bernard J Gersh (Mayo Medical School, Rochester, MN) agreed that the greater all-cause mortality in the DCB group was probably the result of competing, non–peripheral-artery-disease risks entering the equation as the follow-up extended to 2 years, as often happens in long-term analyses.

Clinical practice views stents with caution in the peripheral vasculature, so DCBs likely represent the best step forward from standard balloons for the percutaneous SFA revascularization, according to Laird.

"I think a lot of people have the sense that if they can avoid placing a stent in the femoral artery, they'd like to, to preserve options for future treatments," he said. "The problem with stents is that basically once in-stent restenosis occurs in the leg arteries, particularly if it's diffuse, or if there is in-stent occlusion, then the chances of getting a good long-term result with an endovascular therapy are poor. Having said that, there's been no good direct comparison of a drug-coated-balloon approach vs stenting in a randomized trial."

The study was funded by Medtronic. Laird discloses receiving research grants from WL Gore and Medtronic; consulting for Abbott Vascular, Bard Peripheral Vascular, Boston Scientific, Cordis, and Medtronic; and owning stock equity in Syntervention, AngioSlide, BioCardia, Endoluminal Sciences, Reflow Medical, Eximo, Shockwave Medical, Ostial, and PQ Bypass. Disclosures for the coauthors are listed in the paper.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....