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The present review discusses the use of cyclodextrins and their derivatives to prepare electrospun nanofibers with specific features. Cyclodextrins, owing to their unique capability to form inclusion complexes with hydrophobic and volatile molecules, can indeed facilitate the encapsulation of bioactive compounds in electrospun nanofibers allowing fast-dissolving products for food, biomedical, and pharmaceutical purposes, filtering materials for wastewater and air purification, as well as a variety of other technological applications. Additionally, cyclodextrins can improve the processability of naturally occurring biopolymers helping the fabrication of "green" materials with a strong industrial relevance. Hence, this review provides a comprehensive state-of-the-art of different cyclodextrins-based nanofibers including those made of pure cyclodextrins, of polycyclodextrins, and those made of natural biopolymer functionalized with cyclodextrins. To this end, the advantages and disadvantages of such approaches and their possible applications are investigated along with the current limitations in the exploitation of electrospinning at the industrial level.

The LEADERS FREE trial concluded that the polymer free drug-coated BioFreedom™ stent appeared to be both safer and more effective than bare-metal stents (BMS) with an ISR rate comparable to traditional DES without the need for prolonged DAPT. We implanted 45 BioFreedom™ stents in 34 patients over a 4-month period. 4 patients represented early (106-238 days after the implant procedure) with angina symptoms and severe ISR was detected in all patients. The rate of severe and early ISR detected in our patient population of 11.8% is comparable to that of traditional BMS. Further studies are warranted.

Drug-eluting stents (DES) have revolutionized the way that advanced coronary heart disease is now treated. These devices are associated with much lower rates of restenosis than their bare metal stent counterparts. However, the presence of a polymer coating on the stent surface, which allows for incorporation and sustained release of drug into the artery, has been implicated in the occurrence of late stent thrombosis. Consequently, a great many different polymer-free DES have since been developed. Early approaches involving direct loading of the drug on to unmodified stent surfaces were largely ineffective, which was likely due to suboptimal drug delivery kinetics characterized by very rapid release. It has since been found that stent surface modification strategies at the macro, micro and nanoscale can be used to provide more sustained drug release, with some of these strategies producing clinical results that are comparable to polymer-coated DES. Emerging clinical data on the use of the Cre8, BioFreedom, and the latest Drug Filled Stent from Medtronic Inc. suggest that these particular polymer-free DES may inhibit restenosis without delaying recovery of the endothelium, which would represent a step change improvement in performance. Whilst these devices would therefore appear to be particularly beneficial in treating high bleeding risk patients, the reduction in antiplatelet therapy duration required is likely to be an appealing feature that may see them make a wider impact more generally.