Safety and efficacy of a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent

Late stent thrombosis (LST) following drug-eluting stent (DES) implantation in patients with coronary artery disease (CAD) is often associated with delayed vascular healing, resulting from vascular inflammation and hypersensitivity to durable polymers and drugs. Therefore, DES design, materials, and coatings have been technologically revolutionized. Herein, we designed a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent (AGF-BP-SES), with a sirolimus content of only about one-third of traditional DES. The mechanical performances of AGF-BP-SES during compression and expansion were investigated. The pharmacokinetic (PK) profile of sirolimus was studied in the swine model. The in vivo efficacy of AGF-BP-SES was compared with that of Xience PRIME^® stent. The results showed that AGF-BP-SES exhibited mechanical properties similar to traditional DES, including the rebound ratio of radial contraction/direction, rebound ratio of axial contraction/direction, and inhomogeneity of compression/expansion. Despite utilizing a reduced dose of sirolimus, AGF-BP-SES delivered sirolimus to the coronary artery in a controlled and efficient manner. The stent maintained a safe and effective local drug concentration without local or systemic risks. In the swine model, histopathological indicators predicted safety and biocompatibility of AGF-BP-SES. In conclusion, AGF-BP-SES maintained similar mechanical properties as other stents while reducing the drug-loading capacity, and showed a favorable safety and efficacy profile of the targeted DES.