Response by Schneider et al to Letter Regarding Article, "Treatment Effect of Drug-Coated Balloons Is Durable to 3 Years in the Femoropopliteal Arteries: Long-Term Results of the IN.PACT SFA Randomized Trial"

A Multicenter Randomized Trial Assessing ZENFlow Carrier-Free Drug-Coated Balloon for the Treatment of Femoropopliteal Artery Lesions

Backgrounds and Objectives

Drug-coated balloons (DCBs) have shown promising benefits in improving the outcomes for patients with peripheral artery disease. Several randomized clinical trials have reported that paclitaxel-coated balloon significantly reduce the rates of restenosis and the need for reintervention in comparison with regular balloon angioplasty. Due to the differences in excipients, paclitaxel dose, and coating techniques, variable clinical outcomes have been observed with different DCBs. In this study, we aimed to evaluate the safety and efficacy of a novel ZENFlow carrier-free DCB in the treatment of femoropopliteal artery occlusive disease.

Methods

In this randomized controlled trial conducted at 15 sites, 192 patients with Rutherford class 3–5 were randomly assigned into two groups: drug-coated balloon group and percutaneous transluminal angioplasty group. The primary endpoint was a late lumen loss at 6 months based on blinded angiographic core laboratory evaluations, and the secondary endpoints included primary patency rate, binary restenosis, clinically driven target lesion revascularization, ankle-brachial index, Rutherford class change, and major adverse events.

Results

In this multicenter trial, 93 patients received DCB angioplasty, whereas 99 patients underwent regular balloon angioplasty. The late lumen loss at 6-month follow-up was 0.50 ± 0.82 and 1.69 ± 0.87 mm in the drug-coated balloon and percutaneous transluminal angioplasty groups, respectively (p < 0.001). During the 12-month follow-up period, the drug-coated balloon group showed a significantly higher primary patency rate (54 vs. 31.3%, p = 0.009) and markedly lower rates of target vessel restenosis (22.1 vs. 64.3%, p < 0.001) and clinically driven target lesion revascularization rate (5.4 vs. 19.2%, p = 0.006) than the percutaneous transluminal angioplasty group. Compared with the percutaneous transluminal angioplasty group, the drug-coated balloon group had significant improvements in the ankle-brachial index and Rutherford class. The all-cause mortality rate was comparable, and no device-related deaths occurred in either groups.

Conclusions

Balloon angioplasty using a ZENFlow carrier-free drug-coated balloon is a safe and effective treatment method for femoropopliteal artery lesions. This novel drug-coated balloon catheter achieved satisfactory early and 1-year outcomes in this trial.

Clinical Trial Registration

https://clinicaltrials.gov, identifier: NCT03844724.

Real-World Clinical Outcomes of IN.PACT Admiral Drug-Coated Balloon for Femoropopliteal Artery Disease - 12-Month Results From Japan Post-Market Surveillance Study

BACKGROUND

To confirm the safety and efficacy of the IN.PACT Admiral drug-coated balloon (DCB) based on the indication approved by the Pharmaceuticals and Medical Devices Agency Japan in real-world patients with femoropopliteal artery disease.Methods and Results:IN.PACT PMS Japan was a prospective, multicenter, single-arm, post-market surveillance (PMS) study conducted in Japan that enrolled 304 participants (mean age 75.3±7.9 years). The primary endpoint was primary patency at 6 months following the index procedure, defined as freedom from clinically driven target lesion revascularization (CD-TLR) and freedom from restenosis as determined by duplex ultrasound (DUS) peak systolic velocity ratio (PSVR) ≤2.4 (assessed by the independent DUS core laboratory). Secondary endpoints included acute outcomes, primary patency at 12 months post-index procedure, freedom from CD-TLR, and major adverse events at 12 months. The mean lesion length was 97.81±58.97 mm. The primary endpoint, 6-month primary patency, was 91.3% (240/263). Kaplan-Meier estimates of primary patency and freedom from CD-TLR through 12 months were 91.5% and 94.1%, respectively. The CD-TLR rate was 5.8% (14/240) with low rates of thrombosis (0.8%) and target limb amputation (0.4%) at 12 months.

CONCLUSIONS

The results of this real-world PMS study were consistent with outcomes from previous IN.PACT DCB studies, confirming the safety and efficacy of the IN.PACT Admiral DCB for broader use in patients seen in everyday practice.

Evidence-Experience Gap and Future Perspective on the Treatment of Peripheral Artery Disease

Peripheral artery disease (PAD) is a systemic disease associated with impaired limb function, poor quality of life, and increased cardiovascular morbidity. Its incidence has been dramatically increasing over years because of the emergence of an aging society and the increase in the number of patients with atherosclerotic risk factors. The clustering of these risk factors promotes disease development, reportedly leading to the differential location of atherosclerotic lesions in lower extremity arteries. The clinical presentations of PAD include intermittent claudication and chronic limb-threatening ischemia (CLTI). PAD is associated with a high risk of mortality and morbidity from both cardiovascular and limb events. The therapeutic goals for patients with PAD include 1) relief from PAD-related limb symptoms, 2) the prevention of new-onset and the development and recurrence of PAD, and 3) the prevention of concomitant adverse events due to coronary artery disease (CAD) and cerebrovascular disease (CVD). There are several types of antithrombotic agents, and their main role in patients with PAD is to reduce systemic events mainly including cardiovascular and lower extremity-related events. Currently, the efficacy of direct oral anticoagulant (DOAC) is also suggested by recent clinical trials. Although endovascular therapy (EVT) has been a first-line revascularization strategy for symptomatic PAD, whether clinical outcomes after EVT are comparable to those after surgical bypass therapy remains inconclusive.

An Update on Drug-eluting Technology in Peripheral Arteries to Treat Peripheral Arterial Disease

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Open-Label Multicenter Registry on the Outcomes of In-Stent Restenosis Treated by Balloon Angioplasty with Optical Frequency Domain Imaging in the Superficial Femoral Artery (ISLAND-SFA Study)

Objectives: Balloon angioplasty for in-stent restenosis (ISR) in the superficial femoral artery (SFA) has a high recurrent restenosis rate; however, its mechanism has not been fully and precisely evaluated using high-resolution intravascular imaging. Thus, we aimed to evaluate the relationship between vascular features obtained by optical frequency domain imaging (OFDI) and recurrent restenosis at 6 months. Methods: This was a prospective multicenter single-arm study. OFDI was performed before and after balloon angioplasty, and vascular features were assessed. A multi-layered ISR pattern detected by OFDI was defined as several signal-poor appearances with a high-signal band adjacent to the luminal surface. The primary outcome was defined as recurrent restenosis 6 months after balloon angioplasty. Results: Given that this study was terminated early, only 18 patients completed the 6-month follow-up; of these, 8 developed restenosis. Recurrent restenosis at 6 months tended to be related to a multi-layered ISR pattern (odds ratio (OR), 6.67; 95% confidence interval (CI), 0.81-54.96; p=0.078) and the minimum lumen area (MLA) after balloon angioplasty (OR, 0.71; 95%CI, 0.48-1.04; p=0.077). Conclusion: A multi-layered ISR pattern and MLA after balloon angioplasty detected by OFDI might be risk factors for recurrent ISR in the SFA.

In-vivo vascular application via ultra-fast bioprinting for future 5D personalised nanomedicine

The design of 3D complex structures enables new correlation studies between the engineering parameters and the biological activity. Moreover, additive manufacturing technology could revolutionise the personalised medical pre-operative management due to its possibility to interplay with computer tomography. Here we present a method based on rapid freeze prototyping (RFP) 3D printer, reconstruction cutting, nano dry formulation, fast freeze gelation, disinfection and partial processes for the 5D digital models functionalisation. We elaborated the high-resolution computer tomography scan derived from a complex human peripheral artery and we reconstructed the 3D model of the vessel in order to obtain and verify the additive manufacturing processes. Then, based on the drug-eluting balloon selected for the percutaneous intervention, we reconstructed the biocompatible eluting-freeform coating containing 40 nm fluorescent nanoparticles (NPs) by means of RFP printer and we tested the in-vivo feasibility. We introduced the NPs-loaded 5D device in a rat's vena cava. The coating dissolved in a few minutes releasing NPs which were rapidly absorbed in vascular smooth muscle cell (VSMC) and human umbilical vein endothelial cell (HUVEC) in-vitro. We developed 5D high-resolution self-dissolving devices incorporating NPs with the perspective to apply this method to the personalised medicine.

What are the Pathological Concerns and Limitations of Current Drug-coated Balloon Technology?

The use of endovascular therapy for peripheral artery disease and coronary artery disease has increased and spread worldwide and is considered as the foremost, guideline-based invasive treatment. Drug-coated balloons (DCBs) utilise anti-proliferative drugs similar to drug-eluting stents; however, the do not leave any permanent metallic scaffold. Excipients and drug formulations play a crucial role in innovative DCB technologies and allow for treatment of lesions where stents are not suitable. Although the significance of downstream embolic effects after DCB use remains uncertain, several preclinical studies suggest such side effects might pose safety concerns. Recently, a meta-analysis of randomised controlled trials of paclitaxel devices suggested an association between increased mortality and paclitaxel device use. Subsequently, unfavourable criticism of paclitaxel devices attracted much attention and gave rise to a discussion about the safety of such devices. In this review, we will focus on the novel DCB technologies from the standpoint of preclinical studies and clinical trials, as well as discuss current controversies regarding the increase in death rates from paclitaxel-coated DCBs versus control devices seen in a recent meta-analysis of randomised controlled clinical trials.

Intrinsic coating morphology modulates acute drug transfer in drug-coated balloon therapy

The hallmark of drug-coated balloon (DCB) therapy for the treatment of peripheral vascular disease is that it allows for reopening of the narrowed lumen and local drug delivery without the need for a permanent indwelling metal implant such as a stent. Current DCB designs rely on transferring drugs such as paclitaxel to the arterial vessel using a variety of biocompatible excipients coated on the balloons. Inherent procedural challenges, along with limited understanding of the interactions between the coating and the artery, interactions between the coating and the balloon as well as site-specific differences, have led to DCB designs with poor drug delivery efficiency. Our study is focused on two clinically significant DCB excipients, urea and shellac, and uses uniaxial mechanical testing, scanning electron microscopy (SEM), and biophysical modeling based on classic Hertz theory to elucidate how coating microstructure governs the transmission of forces at the coating-artery interface. SEM revealed shellac-based coatings to contain spherical-shaped microstructural elements whereas urea-based coatings contained conical-shaped microstructural elements. Our model based on Hertz theory showed that the interactions between these intrinsic coating elements with the arterial wall were fundamentally different, even when the same external force was applied by the balloon on the arterial wall. Using two orthogonal cell-based assays, our study also found differential viability when endothelial cells were exposed to titrated concentrations of urea and shellac, further highlighting the need to maximize coating transfer efficiency in the context of DCB therapies. Our results underscore the significance of the excipient in DCB design and suggest that coating microstructure modulates acute drug transfer during device deployment.

Drug-coated Balloons in the Femoropopliteal Region: Dream or Reality?

Peripheral arterial disease is a severe pathology. Several methods have been tested in order to increase the patency rate and the quality of life. The superficial femoral artery is considered a very difficult region due to the continuous movement of the leg that modify the length and the morphology of this vessel. Since their introduction, drug-coated balloons have been correlated with an increased patency rate. Several studies have been performed and nowadays a level 1 evidence is available. Not all the lesions can be treated successfuly with drug-coated balloons. For example in case of heavely calcified lesions vessel preparation is required. This can be performed with atherectomy, scorig balloon, lithoplasty in order to debulk the lesion and increase the drug uptake.