Basic Concepts and Clinical Outcomes of Drug-Eluting Balloons for Treatment of Coronary Artery Disease: An Overview

In Vitro and In Vivo Comparative Evaluation of a Shellac-Ammonium Paclitaxel-Coated Balloon versus a Benchmark Device

Objectives

The present study was designed to compare the characteristics and performance regarding drug delivery of a novel drug-coated balloon (DCB) to a benchmark device (Restore® versus SeQuent® Please) in an in vitro and in vivo model.

Background

Although Restore® and SeQuent® are both paclitaxel-coated, they use different coating excipient, shellac-ammonium salt and iopromide, respectively. Preclinical study comparing these two different commercial DCBs regarding their characteristics and effects on early vascular response is sparse.

Methods

Restore® and SeQuent® DCBs were scanned with electron microscopy for surface characteristic assessment. Both DCBs were transported in an in vitro vessel model for the evaluation of drug wash-off rate and particulate formation. Eighteen coronary angioplasties with either Restore® or SeQuent® DCBs were conducted in 6 swine (three coronary vessels each). Histopathological images of each vessel were evaluated for vessel injury.

Results

The surface of Restore® DCB was smooth and evenly distributed with hardly visible crystal, while SeQuent® DCB showed a rougher surface with relatively larger apparent crystals. Restore® DCB had a lower drug wash-off rate and fewer large visible particles, compared to the SeQuent® DCB. No significant difference in mean injure score was found between Restore® and SeQuent® group.

Conclusion

Our results suggest that Restore® is better in preclinical performance regarding less release of particles and lower drug wash-off rate as compared to SeQuent® Please. The Restore® DCB, using stable amorphous coating and shellac-ammonium salt as an excipient, appears to provide an advantage in drug delivery efficacy; however, further clinical studies are warranted.

Leave Nothing Behind: Treatment of Intracranial Atherosclerotic Disease with Drug-Coated Balloon Angioplasty

PURPOSE

Intracranial atherosclerosis disease (ICAD) is an essential cause of stroke. The characteristics of effective treatment include low periprocedural risk and a sustained treatment effect. Angioplasty with a conventional balloon for ICAD is safe but has a dauntingly high restenosis rate. Drug-coated balloon (DCB) angioplasty might reduce the risk of restenosis while maintaining the overall safety of the procedure.

METHODS

This study included symptomatic ICAD patients with more than 70% stenosis. Intermediate catheters were placed distally, and the lesions were predilated with a conventional balloon, followed by a DCB (SeQuent Please, B Braun, Melsungen, Germany). The primary endpoint was any stroke or death within 30 days or ipsilateral ischemic stroke thereafter. The secondary endpoint was arterial restenosis of more than 50% during follow-up.

RESULTS

A total of 39 sessions of DCB angioplasty were performed for 39 lesions in 35 patients between October 2015 and April 2018 in a single center. All of the DCBs could be navigated to the lesions. Major periprocedural complications were noted in two patients (5.7%, 2/35), and minor periprocedural complications were also noted in two patients (5.7%, 2/35). The average percentages of stenosis of the lesions were 76.6% ± 7% before treatment, 32.4% ± 11.2% after DCB angioplasty, and 25% ± 16% at follow-up. Stenosis over 50% was present in 3 lesions during the follow-up period (8.3%, 3/36).

CONCLUSION

In this study, the application of DCBs to treat ICAD patients was feasible and safe. A larger scale clinical trial is warranted to further evaluate the safety and efficacy of this treatment.

A multicentre, randomised controlled clinical study of drug-coated balloons for the treatment of coronary in-stent restenosis

AIMS

Treatment of in-stent restenosis of coronary stents is challenging. The use of drug-coated balloons (DCB) is a promising technique to treat in-stent restenosis without adding another metal layer. The aim of the AGENT ISR randomised trial is to evaluate angiographic and clinical outcomes in patients with ISR of a previously treated lesion who were treated with either a DCB with a new coating formulation (Agent) or a standard DCB (SeQuent Please).

METHODS AND RESULTS

AGENT ISR is a multicentre, randomised, open-label, non-inferiority study comparing the Agent and SeQuent Please DCB. A total of 125 patients (mean age ~68 years, 18% female) with in-stent restenosis of a previously treated lesion <28 mm in length were randomised at 11 sites in Europe to Agent (n=65) or SeQuent Please (n=60). The primary endpoint, six-month in-stent late lumen loss, in the Agent group (0.397±0.43 mm [n=51]) was non-inferior to that of the SeQuent Please group (0.393±0.536 mm [n=49]), as the two-sided upper 95% confidence boundary for the difference between groups was less than the pre-specified non-inferiority margin of 0.20 (difference 0.004, 95% CI [-0.189, 0.196]; pnon-inferiority=0.046). At one year, mortality was 3.1% in Agent and 1.7% in SeQuent Please patients (p>0.99), target lesion revascularisation 7.7% versus 10.0% (p=0.89), and stent thrombosis 0% versus 3.3% (p=0.44). Similar improvements in quality of life were seen in the two groups.

CONCLUSIONS

In this head-to-head comparison of two DCB, Agent proved to be non-inferior to SeQuent Please for in-stent late lumen loss at six months.

CLINICAL TRIALS REGISTRATION

NCT02151812 (http://clinicaltrials.gov/).

Hydrogen sulfide-releasing peptide hydrogel limits the development of intimal hyperplasia in human vein segments

Currently available interventions for vascular occlusive diseases suffer from high failure rates due to re-occlusive vascular wall adaptations, a process called intimal hyperplasia (IH). Naturally occurring hydrogen sulfide (H2S) works as a vasculoprotective gasotransmitter in vivo. However, given its reactive and hazardous nature, H2S is difficult to administer systemically. Here, we developed a hydrogel capable of localized slow release of precise amounts of H2S and tested its benefits on IH. The H2S-releasing hydrogel was prepared from a short peptide attached to an S-aroylthiooxime H2S donor. Upon dissolution in aqueous buffer, the peptide self-assembled into nanofibers, which formed a gel in the presence of calcium. This new hydrogel delivered H2S over the course of several hours, in contrast with fast-releasing NaHS. The H2S-releasing peptide/gel inhibited proliferation and migration of primary human vascular smooth muscle cells (VSMCs), while promoting proliferation and migration of human umbilical endothelial cells (ECs). Both NaHS and the H2S-releasing gel limited IH in human great saphenous vein segments obtained from vascular patients undergoing bypass surgery, with the H2S-releasing gel showing efficacy at a 5x lower dose than NaHS. These results suggest local perivascular H2S release as a new strategy to limit VSMC proliferation and IH while promoting EC proliferation, hence re-endothelialization. STATEMENT OF SIGNIFICANCE: Arterial occlusive disease is the leading cause of death in Western countries, yet current therapies suffer from high failure rates due to intimal hyperplasia (IH), a thickening of the vascular wall leading to secondary vessel occlusion. Hydrogen sulfide (H2S) is a gasotransmitter with vasculoprotective properties. Here we designed and synthesized a peptide-based H2S-releasing hydrogel and found that local application of the gel reduced IH in human vein segments obtained from patients undergoing bypass surgery. This work provides the first evidence of H2S efficacy against IH in human tissue, and the results show that the gel is more effective than NaHS, a common instantaneous H2S donor.

Recanalization of bilateral axillaris/brachialis artery occlusion in a patient with Takayashu arteritis: First case report on using a novel drug-coated nitinol "chocolate" balloon catheter

When fibrosis develops in Takayasu arteritis (TA), endovascular treatment may become necessary. A 63-year-old woman with TA underwent PTA with a nitinol-structured (chocolate-like) drug-coated balloon (C-DEB PTA). She remained in remission for >1 year. The case may foster research into the use of C-DEB PTA in TA.