Evaluation of a novel paclitaxel-eluting stent with a bioabsorbable polymeric surface coating in the porcine artery injury model.

Purpose: Drug-eluting stents (DES) are unique in allowing sustained release after a single short intervention. The challenge with DES still remaining is the optimal combination of a biocompatible drug-eluting matrix including an antiproliferative drug. We studied the role of a novel paclitaxel-eluting stent with a bioabsorbable polymer coating in preventing vascular restenosis in the porcine artery injury model.

Material And Methods: Bare metal stents (BMS); polymer-coated-only stents (POLY); and polymer-based paclitaxel-eluting stents (PACL) were randomly implanted in pig femoral arteries. The dose density of paclitaxel was 1 microg/mm2 with in vitro studies demonstrating a gradual elution over a course of 6 month.

Results: After 1-, 3- and 6-month follow-up, respectively, the animals underwent angiographic restudy and were terminated for histomorphometrical and histopathological analyses. At 1 month, the PACL group had the lowest histological percent stenosis when compared to the BMS and POLY groups (20 +/- 4% vs 39 +/- 6% and 41 +/- 6%, respectively, P < 0.05). At 3 months, the PACL group still presents the lowest level of histological percent stenosis among the three groups (27 +/- 6% vs 50 +/- 10% and 46 +/- 5%, respectively, P < 0.01). Six months later, the PACL group showed a similar histological percent stenosis as the BMS and POLY groups (44 +/- 9% vs 56 +/- 11% and 53 +/- 9%, respectively, P = 0.145).

Conclusions: This study shows favourable vascular compatibility and efficacy for a novel DES to inhibit in-stent neointima formation and preserve lumen area in the porcine artery model.