Gray WA, et al. - The polymer-coated, paclitaxel-eluting Eluvia stent was compared, in terms of safety and effectiveness, with the polymer-free, paclitaxel-coated Zilver PTX stent for treatment of femoropopliteal artery segment lesions in the IMPERIAL study. Among patients treated for femoropopliteal peripheral artery disease, the observed primary patency and major adverse events at 12 months were non-inferior in those treated with the Eluvia stent vs the Zilver PTX stent.

Methods

• This was a randomized, single-blind, non-inferiority study conducted at 65 centers in Austria, Belgium, Canada, Germany, Japan, New Zealand, and the US.
• Researchers enrolled patients with symptomatic lower-limb ischemia manifesting as claudication (Rutherford category 2, 3, or 4) with atherosclerotic lesions in the native superficial femoral artery or proximal popliteal artery.
• A site-specific, web-based randomization schedule was used to randomly assign (2:1) patients to receive treatment with Eluvia or Zilver PTX.
• Until the completion of 12 months of follow-up in all participants, all patients, site personnel, and investigators were masked to treatment assignment.
• Primary patency (defined as a peak systolic velocity ratio ≤2.4, without clinically driven target lesion revascularization or bypass of the target lesion) was assessed as the primary efficacy endpoint.
• They also evaluated major adverse events (ie, all causes of death through 1 month, major amputation of target limb through 12 months, and target lesion revascularization through 12 months) as the primary safety endpoint.
• They set a non-inferiority margin of -10% at 12 months.
• On completion of 12 months of follow-up in the minimum sample size required for adequate statistical power, they carried out primary non-inferiority analyses.
• All patients who had completed 12 months of follow-up or had a major adverse event through 12 months were analyzed in primary safety non-inferiority analysis.

Results

• Randomization of 465 patients to Eluvia (n=309) or to Zilver PTX (n=156) was done between December 2, 2015 and February 15, 2017.
• Findings demonstrated non-inferiority for both efficacy and safety endpoints at 12 months: the estimated primary patency was 86.8% (231/266) and 81.5% (106/130) in the Eluvia group and in the Zilver PTX group, respectively (difference 5.3% [one-sided lower bound of 95% CI -0.66]; p<0.0001).
• No major adverse event was observed at 12 months in 259 (94.9%) of 273 patients in the Eluvia group and 121 (91.0%) of 133 patients in the Zilver PTX group (difference 3.9% [one-sided lower bound of 95% CI -0.46]; p<0.0001).
• In either group, no deaths were reported.
• A major amputation was performed on one patient in the Eluvia group and 13 patients in each group needed target lesion revascularization.