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

Current Management of In-Stent Restenosis

In-stent restenosis (ISR) remains the primary cause of target lesion failure following percutaneous coronary intervention (PCI), resulting in 10-year incidences of target lesion revascularization at a rate of approximately 20%. The treatment of ISR is challenging due to its inherent propensity for recurrence and varying susceptibility to available strategies, influenced by a complex interplay between clinical and lesion-specific conditions. Given the multiple mechanisms contributing to the development of ISR, proper identification of the underlying substrate, especially by using intravascular imaging, becomes pivotal as it can indicate distinct therapeutic requirements. Among standalone treatments, drug-coated balloon (DCB) angioplasty and drug-eluting stent (DES) implantation have been the most effective. The main advantage of a DCB-based approach is the avoidance of an additional metallic layer, which may otherwise enhance neointimal hyperplasia, provide the substratum for developing neoatherosclerosis, and expose the patient to a persistently higher risk of coronary ischemic events. On the other hand, target vessel scaffolding by DES implantation confers relevant mechanical advantages over DCB angioplasty, generally resulting in larger luminal gain, while drug elution from the stent surface ensures the inhibition of neointimal hyperplasia. Nevertheless, repeat stenting with DES also implies an additional permanent metallic layer that may reiterate and promote the mechanisms leading to ISR. Against this background, the selection of either DCB or DES on a patient- and lesion-specific basis as well as the implementation of adjuvant treatments, including cutting/scoring balloons, intravascular lithotripsy, and rotational atherectomy, hold the potential to improve the effectiveness of ISR treatment over time. In this review, we comprehensively assessed the available evidence from randomized trials to define contemporary interventional treatment of ISR and provide insights for future directions.

Comparative efficacy of interventional therapies and devices for coronary in-stent restenosis: A systematic review and network meta-analysis of randomized controlled trials

Background

In-stent restenosis (ISR) has become a significant obstacle to interventional therapy for atherosclerotic cardiovascular disease. The optimal percutaneous coronary intervention (PCI) strategy for patients with coronary ISR remains controversial. This network meta-analysis (NMA) was aimed to compare and estimate the effectiveness of different PCI strategies and commercial devices for the treatment of patients with coronary ISR.

Methods

In present study, we systematically searched PubMed, Embase, Web of Science, and Cochrane Library from database inception to October 20, 2022, to identify randomized controlled trials. We included studies comparing various PCI strategies for the treatment of any type of coronary ISR. The study was registered with PROSPERO, CRD 42022364308.

Results

We included 44 eligible trials including 8479 patients, 39 trials comparing the treatment effects of 10 PCIs, and 5 trials comparing the efficacy between different types of drug-eluting stent (DES) or drug-coated balloon (DCB) devices. Among the PCIs, everolimus-eluting stent was the optimal strategy considering target lesion revascularization (TLR), percent diameter stenosis (%DS), and binary restenosis (BR), and sirolimus-coated balloon was the optimal strategy considering late lumen loss (LLL). In the comparison of commercial devices, the combination strategy excimer laser coronary angioplasty plus SeQuent Please paclitaxel-coated balloon showed promising therapeutic prospects.

Conclusions

DCB and DES remain the preferred treatment strategies for coronary ISR, considering both the primary clinical outcome (TLR) and the angiographic outcomes (LLL, BR, %DS). Personalized combination interventions including DCB or DES hold promise as a novel potential treatment pattern for coronary ISR.

Paclitaxel-Coated Balloon vs Uncoated Balloon for Coronary In-Stent Restenosis: The AGENT IDE Randomized Clinical Trial

Importance

Drug-coated balloons offer a potentially beneficial treatment strategy for the management of coronary in-stent restenosis. However, none have been previously evaluated or approved for use in coronary circulation in the United States.

Objective

To evaluate whether a paclitaxel-coated balloon is superior to an uncoated balloon in patients with in-stent restenosis undergoing percutaneous coronary intervention.

Design, Setting, and Participants

AGENT IDE, a multicenter randomized clinical trial, enrolled 600 patients with in-stent restenosis (lesion length <26 mm and reference vessel diameter >2.0 mm to ≤4.0 mm) at 40 centers across the United States between May 2021 and August 2022. One-year clinical follow-up was completed on October 2, 2023.

Interventions

Participants were randomized in a 2:1 allocation to undergo treatment with a paclitaxel-coated (n = 406) or an uncoated (n = 194) balloon.

Main Outcomes and Measures

The primary end point of 1-year target lesion failure-defined as the composite of ischemia-driven target lesion revascularization, target vessel-related myocardial infarction, or cardiac death-was tested for superiority.

Results

Among 600 randomized patients (mean age, 68 years; 157 females [26.2%]; 42 Black [7%], 35 Hispanic [6%] individuals), 574 (95.7%) completed 1-year follow-up. The primary end point at 1 year occurred in 17.9% in the paclitaxel-coated balloon group vs 28.6% in the uncoated balloon group, meeting the criteria for superiority (hazard ratio [HR], 0.59 [95% CI, 0.42-0.84]; 2-sided P = .003). Target lesion revascularization (13.0% vs 24.7%; HR, 0.50 [95% CI, 0.34-0.74]; P = .001) and target vessel-related myocardial infarction (5.8% vs 11.1%; HR, 0.51 [95% CI, 0.28-0.92]; P = .02) occurred less frequently among patients treated with paclitaxel-coated balloon. The rate of cardiac death was 2.9% vs 1.6% (HR, 1.75 [95% CI, 0.49-6.28]; P = .38) in the coated vs uncoated balloon groups, respectively.

Conclusions and Relevance

Among patients undergoing coronary angioplasty for in-stent restenosis, a paclitaxel-coated balloon was superior to an uncoated balloon with respect to the composite end point of target lesion failure. Paclitaxel-coated balloons are an effective treatment option for patients with coronary in-stent restenosis.

Trial Registration

ClinicalTrials.gov Identifier: NCT04647253.

Biological differences of three paclitaxel- and sirolimus-coated balloons on coronary lesions in a rabbit model

BACKGROUND

Drug-coated balloons (DCBs) are important treatment options for coronary artery disease; however, randomised controlled trials comparing various DCB technologies are sparse, and further investigations are needed.

AIMS

This preclinical study aimed to histologically and biologically compare the drug effects and safety of a low-dose paclitaxel-coated DCB (PCB; AGENT), a regular-dose PCB (SeQuent Please NEO) and a sirolimus-coated DCB (SCB; MagicTouch).

METHODS

The DCBs were inflated in the healthy iliac arteries of 18 rabbits, which were euthanised after 28 days. The treated iliac arteries and distal skeletal muscles were histopathologically evaluated, and drug concentrations were measured.

RESULTS

In the histopathological evaluation, the medial smooth muscle cell loss score regarding depth, an indicator of drug efficacy, was significantly higher with AGENT and SeQuent Please NEO than with MagicTouch (4.0 [3.6-4.0] vs 3.7 [3.7-4.0] vs 2.2 [2.0-2.4]), with significant differences in comparisons between AGENT and MagicTouch (p<0.01) and between SeQuent Please NEO and MagicTouch (p<0.01). AGENT and SeQuent Please NEO showed comparable drug concentrations in the treated artery (p=0.61). In contrast, the drug concentrations in distal skeletal muscles were the highest for MagicTouch, followed by SeQuent Please NEO and AGENT (28.07 [13.19-52.46] ng/mg vs 0.66 [0.22-3.76] ng/mg vs 0.25 [0.04-3.23] ng/mg, respectively).

CONCLUSIONS

This study demonstrated that PCBs might have higher efficacy and lower drug concentrations in distal skeletal muscles than the MagicTouch SCB. The efficacy of the AGENT low-dose PCB and the SeQuent Please NEO regular-dose PCB was comparable.

Intrastent Restenosis: A Comprehensive Review

The primary objective of this paper is to delineate and elucidate the contemporary advancements, developments, and prevailing trajectories concerning intrastent restenosis (ISR). We aim to provide a thorough overview of the most recent developments in this area, covering various aspects such as pathophysiological insights, therapeutic approaches, and new strategies for tackling the complex challenges of ISR in modern clinical settings. The authors have undertaken a study to address a relatively new medical challenge, recognizing its significant impact on the morbidity and mortality of individuals with cardiovascular diseases. This effort is driven by the need to fully understand, analyze, and possibly improve the outcomes of this emerging medical issue within the cardiovascular disease field. We acknowledge its considerable clinical implications and the necessity for innovative methods to mitigate its effects on patient outcomes. Therefore, our emphasis was directed towards elucidating the principal facets of the condition's prevalence, expounding upon the foundational mechanisms underscoring conspicuous restenosis, and delineating the risk factors relevant in shaping the contemporary landscape of diagnostic and therapeutic modalities. This thorough examination aims to provide a comprehensive understanding of the various dimensions of the condition, including epidemiological data, pathophysiological complexities, and clinical considerations critical for evaluating and enhancing current diagnostic and treatment approaches.

Drug-Coated Balloon for the Treatment of Small Vessel Coronary Artery Disease - A Randomized Non-Inferiority Trial

BACKGROUND

Drug-coated balloons (DCB) have shown promising results for the treatment of in-stent restenosis (ISR) and small vessel disease (SVD). However, data comparing the treatment efficacy of different DCBs are limited.Methods and Results: AGENT Japan is a prospective randomized controlled trial that compares the Agent balloon coated with a low-dose formulation of paclitaxel (2 μg/mm²) to the SeQuent Please paclitaxel-coated balloon (3 μg/mm²) for the treatment of SVD. Patients with target lesion length ≤28 mm and reference diameter between ≥2.00 and <3.00 mm were randomized 2 : 1 for treatment with Agent (n=101) or SeQuent Please (n=49). This trial also includes a separate single-arm substudy evaluating the clinical safety and effectiveness of Agent in patients with ISR. The primary endpoint of 6-month target lesion failure (TLF) was observed in 3.0% of Agent and 0.0% of SeQuent Please patients (difference=3.0%; 97.5% upper confidence bound [UCB]=9.57%, which is less than the prespecified margin of 13.2%; P_{non-inferiority}=0.0012). There were no deaths or thrombosis, and angiographic and quality-of-life outcomes were comparable between groups. The AGENT Japan ISR substudy (n=30) primary endpoint was met because the one-sided 97.5% UCB for 6-month TLF (3.3%) was significantly less than the study success criterion of 15.1% (97.5% UCB=9.8%; P<0.0001).

CONCLUSIONS

Data from this study demonstrate good clinical outcomes with the Agent DCB when used to treat patients with SVD or ISR.

Technical success, clinical efficacy, and insight into the causes of restenosis after the percutaneous coronary intervention of de novo coronary artery lesions using a paclitaxel-coated balloon with citrate ester excipient

Objectives

The aim of this all-comers registry study was to investigate the technical success, clinical efficacy, and safety of a drug-coated balloon (DCB) with paclitaxel combined with citrate ester excipient (CEE) in percutaneous coronary intervention (PCI) of de novo coronary lesions in an all-comers population.

Materials and methods

A total of 338 consecutive PCIs using the DCB (CEE)-only approach comprising 406 de novo lesions were included in the study. Technical success was determined by the successful delivery of the device and no need for bailout stenting.

Results

The mean follow-up time was 25 ± 12 months. The mean age of patients was 71 ± 11 years, and 48% had the acute coronary syndrome. A total of 55% of the patients were at risk of factor bleeding. The delivery of DCB was successful in 98% of cases. The overall technical success rate was 83%. Bailout stenting was used in 9% of lesions. Rotational atherectomy was used in 11% of cases before the DCB-only approach. The mean diameter of the DCBs used was 2.7 ± 0.5 mm and 38% of DCBs were large (≥3.0 mm). The 12-month MACE rates were 5.4 ± 1.7 and 18.3 ± 3.1% in stable CAD and in ACS, respectively. The respective target lesion revascularization (TLR) rates were 3.0 ± 1.3 and 8.5 ± 2.3%. Unacceptable acute recoil (>30%) was found in 74% of cases that needed repeat revascularization. No acute vessel closures occurred after DCB treatment.

Conclusion

The DCB-only strategy using a paclitaxel-coated (CEE) device was technically feasible, safe, and effective in an all-comers population. Acute recoil was found as a significant cause of restenosis after the DCB-only strategy.

Sirolimus-coated balloon versus everolimus-eluting stent in de novo coronary artery disease: Rationale and design of the TRANSFORM II randomized clinical trial

BACKGROUND

Percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation is a widely adopted strategy for the treatment of de novo coronary artery disease. DES implantation conveys an inherent risk for short- and long-term complications, including in-stent restenosis and stent thrombosis. Drug-coated balloons are emerging as an alternative approach to fulfill the "leaving nothing behind" principle and avoid long-term DES-related complications.

DESIGN

TRANSFORM II is an investigator-initiated, multicenter, noninferiority, randomized clinical trial, testing a sirolimus-coated balloon (SCB) versus the standard of care for native coronary vessels with a 2-3 mm diameter, in terms of 12-month target lesion failure (TLF; primary endpoint) and net adverse cardiovascular events (coprimary endpoint). Patients undergoing PCI will be randomized to be treated with either SCB or new-generation everolimus-eluting stent and will be followed up clinically for up to 60 months. Assuming a TLF rate of 8% at 12 months with DES, a sample size of 1325 patients was chosen to ensure an 80% power to detect a 1.5% lower incidence in the SCB group with a type I error rate of 0.05. The TRANSFORM II trial is registered on clinicaltrials.gov (identification number NCT04893291). Several substudies, including an optical coherence tomography assessment at 9 months (intracoronary imaging substudy), will investigate the study device in different clinical and lesion settings.

CONCLUSIONS

The randomized TRANSFORM II trial will determine whether a novel SCB is noninferior to a current everolimus-eluting stent when adopted for the treatment of de novo lesions in coronary vessels with a diameter between 2 and 3 mm.

Management of in-stent restenosis

In-stent restenosis (ISR) remains the most common cause of stent failure after percutaneous coronary intervention (PCI). Recent data suggest that ISR-PCI accounts for 5-10% of all PCI procedures performed in current clinical practice. This State-of-the-Art review will primarily focus on the management of ISR but will begin by briefly discussing diagnosis and classification. We then move on to detail the evidence base underpinning the various therapeutic strategies for ISR before finishing with a proposed ISR management algorithm based on current scientific data.

A prospective trial of a novel low-dose paclitaxel-coated balloon therapy in patients with restenosis in drug-eluting coronary stents Intracoronary Stenting and Angiographic Results: Optimizing Treatment of Drug Eluting Stent In-stent REstenosis 3A (ISAR-DESIRE 3A)

OBJECTIVES

We investigated the clinical efficacy of a paclitaxel-coated balloon (PCB) with a novel matrix coating and reduced drug concentration in comparison with a widely used PCB with iopromide excipient.

METHODS

We prospectively enrolled patients with restenosis in drug-eluting stents. All patients were treated with a novel low-dose PCB with citrate-based excipient (Agent PCB). Angiographic follow-up was scheduled at 6-8 months. Outcomes were compared against those of patients treated with iopromide excipient PCB (SeQuent Please PCB) enrolled in a trial with identical inclusion and exclusion criteria. The primary endpoint was percent diameter stenosis (%DS) at follow-up angiography. The primary hypothesis was that the investigational device would be non-inferior to the control device (ClinicalTrials.gov Identifier: NCT02367495).

RESULTS

One hundred twenty-five patients with 151 lesions were enrolled. Mean age was 68.1 ± 10.2 years, 40.8% had diabetes mellitus and 80.1% had focal morphology in-stent restenosis. Follow-up angiography data at 6-8 months was available for 102 (81.6%) patients. The Agent PCB was non-inferior to the SeQuent Please PCB in terms of the primary endpoint (38.9 ± 17.5 vs. 38.1 ± 21.5%; p _{non-inferiority}  = 0.0056). Late lumen loss was also comparable between the groups (0.35 ± 0.55 vs. 0.37 ± 0.59; p = 0.71). There was no difference between the groups in the incidence of TLR (27.7% vs. 22.1%; p = 0.31), death or myocardial infarction (4.2% vs. 4.4%; p = 0.92) or target lesion thrombosis (1.0% vs. 0.7%; p = 0.93).

CONCLUSION

In patients with DES restenosis, angioplasty with a novel PCB with citrate-based excipient was non-inferior to PCB with iopromide excipient in terms of angiographic outcome.

Rationale and design of a randomized study comparing the agent drug coated balloon to plain old balloon angioplasty in patients with In-stent restenosis

BACKGROUND

Drug-coated balloon (DCB) technology was developed as an alternative treatment for obstructive coronary artery disease (CAD) and in-stent restenosis (ISR). Management of coronary ISR is clinically challenging and frequently encountered in practice. The Agent DCB uses an inactive excipient to effectively deliver a targeted, therapeutic dose of paclitaxel to the vessel wall.

STUDY DESIGN

AGENT IDE is a prospective, multicenter, randomized controlled trial to evaluate superiority of the Agent DCB to balloon angioplasty in treating patients with ISR. A total of 480 patients with ISR of a previously treated lesion length <26 mm and reference vessel diameter >2.0 mm to ≤4.0 mm will be initially randomized. Subjects presenting with recent myocardial infarction (MI), complex lesions, or thrombus in the target vessel will be excluded. An adaptive group sequential design with one formal interim analysis for sample size re-estimation will be conducted, and the sample size may be increased to a maximum of 600 subjects. The primary endpoint is the rate of 12-month target lesion failure (TLF; composite of any ischemia-driven revascularization of the target lesion (TLR), target vessel related MI, or cardiac death) and will be tested for superiority in the test arm against the control. Functional status and general health-related quality of life will be measured by changes in the EQ-5D scores. Subjects will be followed for 5 years following the index procedure.

CONCLUSION

This study will prospectively evaluate the safety and efficacy of Agent DCB in patients treated for coronary ISR.

Ostial lesion of the anterior descending coronary artery treated via Szabo technique supported by stent boost imaging: a case report

Background

Stenosis at the opening and bifurcation of the anterior descending branch and circumflex branch around the end of the left main trunk is difficult to repair. Accurate positioning of a stent is the key problem.

Case presentations

Here we report the case of a 61-year-old man who suffered from paroxysmal chest pain for 1 year, without history of diabetes or hypertension. The coronary computed tomography showed mixed plaques in the proximal part of the anterior descending artery, with stenosis severe at 80–90%. The emergency coronary angiography showed occlusion of the anterior descending artery. During percutaneous coronary intervention, a drug-eluting stent was implanted into the anterior descending artery using the Szabo technique, supported by stent boost (StentBoost) imaging to pinpoint the location of the lesion. The patient’s paroxysmal chest pain was relieved after the procedure.

Conclusion

We used StentBoost to verify the accuracy of stent placement and the Szabo technique to rectify long-term coronary stenosis, which achieved satisfactory results. Combining the Szabo technique with StentBoost imaging was helpful to accurately evaluate the area and locate the stent when treating this ostial lesion of the anterior descending coronary artery.