Bioresorbable Scaffold-Based Controlled Drug Delivery for Restenosis

Bioresorbable scaffolds have emerged as a potential alternative to non-erodible metal implants to alleviate the long-term risk of permanent device vascular implant-related adverse events. Bioresorbable scaffolds provide a temporary mechanical support function until the vessel reaches complete healing, and the implant progressively disappears and vasomotion resumes. A polymer matrix with embedded drugs coated onto the scaffold surface degrades slowly, reducing the size from the exterior toward the interior, and this allows controlled drug release to a local vascular segment. Drug elution from a bioresorbable scaffold system is characterized by a rapid initial release that achieves high concentration along the intimal surface, which is designed to prevail vascular dilation-induced injury and formation of neointimal hyperplasia. This review highlights diverse types of bioresorbable biomaterials as vascular scaffolds, drug release kinetics, adaptive arterial wall remodeling, and complexities in the advancement of vascular scaffolds to treat restenosis.