Comparison of Particulate Embolization After Femoral Artery Treatment with IN.PACT Admiral Versus Lutonix 035 Paclitaxel-Coated Balloons in Healthy Swine

Purpose: Different carrier excipients unique to individual drug-coated balloons (DCBs) may influence embolic safety characteristics in peripheral vascular territories through embolization of released particulates. A comparator study of IN.PACT Admiral vs Lutonix 035 balloons in healthy swine was therefore performed to assess which balloon produces more downstream emboli.

Materials And Methods: Single or overlapping 80-mm IN.PACT and Lutonix 035 DCBs were assessed in the femoral arteries of 21 swine with 28- and 90-day follow-up, with standard balloon angioplasty as a control. Histologic analysis of arterial wall and downstream skeletal muscle and coronary band was performed. This analysis was supported by an analytic measurement of paclitaxel levels.

Results: IN.PACT DCBs demonstrated a more pronounced change in medial wall composition, characterized by a paclitaxel-induced loss of medial smooth muscle cells accompanied by increased proteoglycans. The percentage of sections with arterioles exhibiting paclitaxel-associated fibrinoid necrosis in downstream tissues was higher at 90 days with overlapping IN.PACT DBCs compared with Lutonix 035 DCBs (46.2% [interquartile range, 19.2-57.7] vs 0.0% [0.0-11.5]; P = .01), with similar trends noted for 28-day single and overlapping DCBs. Drug analysis in parallel tissues further confirmed higher paclitaxel concentrations in nontarget tissues for IN.PACT than Lutonix 035 balloons for single and overlapping configurations at both time points. Rare embolic crystalline material was observed in downstream tissues, but only for IN.PACT balloons.

Conclusions: There was more fibrinoid necrosis in tissues treated with IN.PACT DCBs compared with Lutonix DCBs, suggesting increased emboli debris with higher paclitaxel levels.