Eluvia drug-eluting vascular stent system for the treatment of symptomatic femoropopliteal lesions

Comparative Evaluation of Two Paclitaxel-Coated Stents in an Experimental Setting

INTRODUCTION

Unlike paclitaxel-coated balloons, pre-clinical data comparing different paclitaxel-coated stents (PCSs) are weak. The study objective was to compare the features of the 2 main PCSs: Eluvia® (Boston Scientific, Marlborough, MA) versus ZilverPTX® (Cook Medical, Bloomington, IN).

METHOD

Analysis was carried out on 12 pigs divided into 2 groups: Eluvia® (n=6) and ZilverPTX® (n=6). The pigs received the PCS corresponding to their group in each external iliac artery and were paired one by one, to examine 6 different post-implantation timepoints: after 30 minutes, 6 hours, 24 hours, 3 days, 7 days, and 14 days. The paclitaxel concentration measurements and the histological analysis were carried out under blind testing on the plasma, arterial, lymph node, and muscle samples. A linear regression model and Wilcoxon Mann-Whitney test were used to study the variables.

RESULTS

The plasma paclitaxel rate decrease over 24 hours after PCS implantation was significantly different between the two groups, expressed by the correlation coefficient 0.19 (0.14-0.23; p<0.001) with an undetectable concentration at the 10th hour for Eluvia® versus 3 days for ZilverPTX®. Significantly higher paclitaxel concentrations with ZilverPTX® PCS were observed in muscle samples at each timepoint: extensor digitorum brevis 3.2 (1.17-5.23; p=0.005), biceps femoris 4.27 (2.27-6.26; p<0.001), semi-tendinosus 3.79 (1.85-5.73; p=0.001), tibialis anterior 3.0 (1.37-4.64; p=0.001), and in the femoral nodes 2.27±1.74 ng/g versus 0.14±0.13 ng/g (p<0.001). Histological analysis revealed a trend for more marked intimal inflammation in the arteries stented with ZilverPTX® (p=0.063), especially after the 7th and 14th days.

CONCLUSION

Such a difference in the concentration of paclitaxel in the plasma, muscles, and lymph nodes between the two stents was higher than expected based on differences in device design. The clinical consequences of these results remain to be elucidated, particularly regarding the concerning presence of paclitaxel in muscles and adjacent lymph nodes.

CLINICAL IMPACT

This experimental study compares 2 paclitaxel-coated stents. It demonstrates that differences in stent designs and drug features (coatings and concentrations) translate into differences in terms of concentrations of paclitaxel in the plasma, muscles, and lymph nodes. Our results favor the Eluvia® stent over the ZilverPTX® stent, although more studies are required to confirm this conclusion.

Current developments in endovascular therapy of peripheral vascular disease

More than 200 million people worldwide have peripheral artery disease (PAD) or its most severe manifestation, critical limb ischemia (CLI). While endovascular treatment has become first line therapy in most cases, a number of challenges remain for optimal treatment of femoropopliteal (FP) or infrapopliteal (IP) disease, especially when these lesions are severely calcified, chronic total occlusions (CTOs) or in-stent restenosis (ISR). Continued evolution of technologies has significantly improved the outcomes for endovascular treatment. A number of new devices are in the pipeline right now, including new paclitaxel eluting stents and balloons, intravascular lithotripsy to treat severely calcified lesions, adventitial delivery of anti-restenotic agents to limit restenosis rates, and percutaneous femoro-popliteal bypass.

Newly approved devices for endovascular treatment of femoropopliteal disease: a review of clinical evidence

Introduction: Femoropopliteal lesions account for a significant proportion of endovascular interventions for peripheral artery disease. In this manuscript, we review the literature on the application of newly approved devices in the treatment of atherosclerotic lesions at this segment.Areas covered: New drug-coating technologies provide sustained drug-eluting over time and better scaffolds are more resistant to the increased biomechanical stress at the femoropopliteal segment. Thus, the newer drug-eluting stents (i.e. Eluvia®), nitinol interwoven stents (i.e. Supera®), and drug-coated balloons (i.e. Stellarex®) are associated with improved pharmacokinetic profiles and promising primary patency rates. A major predictor of technical failure and restenosis is the calcification of the target vessel. Recently, intravascular lithotripsy of calcified lesions at the femoropopliteal segment with the Shockwave® balloon was introduced as a feasible treatment option for these complex lesions. Finally, we also describe the Tack Endovascular System®, the first-of-its-type, for the repair of post-angioplasty dissections.Expert opinion: The use of innovative stent designs and novel drug-coating, the application of adjunctive intravascular lithotripsy, and the combined use of new devices treating complications might improve the overall outcomes of angioplasty, thereby promising favorable outcomes even for more complex lesions.