Preclinical assessment of bioresorbable scaffolds and regulatory implication

Bioresorbable stents (BRSs) represent an intuitively appealing technology with potential to solve some of the issues associated with the use of metallic drug eluting stents (DESs) over the last few years. Currently, three BRSs with distinct design properties have received CE (Conformité Européene) mark approval for use in Europe (Figure 3.5.1). Despite the early adoption of this technology in clinical practice after achieving favorable initial clinical results, some concerns remain with respect to acute thrombogenicity and sustainability of clinical efficacy especially when targeting atherosclerotic coronary lesions with greater complexity [1]. In addition to bench testing of material characteristics and toxicological evaluation of device components, preclinical studies represent an important milestone in the safety evaluation of BRSs. In vivo testing in preclinical animals followed by histologic assessment at various time points for vascular response during biodegradation is key in the understanding of the safety profile of BRSs.