The DES BTK Vascular Stent System vs PTA in Subjects With Critical Limb Ischemia

Study Overview
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Brief Summary
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Single phased global, prospective, multicenter clinical trial designed to demonstrate a superior patency rate and acceptable safety in below the knee arteries with lesions treated with the DES BTK Vascular Stent System vs. percutaneous transluminal angioplasty (PTA).

Detailed Description
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A global, prospective, multicenter, 2:1 randomized trial evaluating the safety and effectiveness of the DES BTK Vascular Stent System compared to standard percutaneous transluminal angioplasty to treat infrapopliteal artery lesions in subjects with critical limb ischemia(CLI). Approximately 201 subjects will be randomized/enrolled to support a 2:1 randomization.

Official Title
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A Randomized Trial Comparing the Drug-Eluting Stent (DES) Below-the-Knee (BTK) Vascular Stent System (DES BTK Vascular Stent System) vs Percutaneous Transluminal Angioplasty (PTA) Treating Infrapopliteal Lesions in Subjects With Critical Limb Ischemia

Conditions
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Critical Limb Ischemia

Intervention / Treatment
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* Combination Product: Drug Eluting Stent - Below the Knee
* Device: Standard PTA Control Arm


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is 18 years or older and has signed and dated the trial informed consent form (ICF) Subject is willing and able to comply with the trial testing, procedures and follow-up schedule Subject has chronic, symptomatic lower limb ischemia, determined by Rutherford categories 4 or 5 in the target limb, with wound(s) confined to toes/forefoot Subject is a male or non-pregnant female. If female of child-bearing potential, and if sexually active must be using, or agree to use, a medically-acceptable method of birth control as confirmed by the investigator Intra-procedure Inclusion Criteria: Stenotic, restenotic or occlusive target lesion(s) located in the tibioperoneal trunk, anterior tibial, posterior tibial and/or peroneal artery(ies). Target lesion(s) must be at least 4cm above the ankle joint A single target lesion per vessel, in up to 2 vessels, in a single limb Degree of stenosis ≥ 70% by visual angiographic assessment Reference vessel diameter is between 2.5 - 3.25mm for phase A RCT Total target lesion length (or series of lesion segments) to be treated is ≤ 70 mm for phase A RCT prior to the data monitoring committee's approval for stent overlap. (Note: Lesion segment(s) must be fully covered with one DES BTK stent, if randomized to stent) Total target lesion length (or series of lesion segments) to be treated is ≤ 140 mm for phase A RCT after the data monitoring committee's approval for stent overlap (Note: Lesion segment(s) must be fully covered with up to two DES BTK stents, if randomized to stent) Target vessel(s) reconstitute(s) at or above the stenting limit zone (4cm above the ankle joint) Target lesion(s) is located in an area that may be stented without blocking access to patent main branches Treatment of all above the knee inflow lesion(s) is successful prior to treatment of the target lesion Guidewire has successfully crossed the target lesion(s) Exclusion Criteria: Life expectancy ≤ 1year Stroke ≤ 90 days prior to the procedure date Prior or planned major amputation in the target limb Previous surgery in the target vessel(s) (including prior ipsilateral crural bypass) Previously implanted stent in the target vessel(s) Failed PTA of target lesion/vessel ≤ 60 days prior to the procedure date Renal failure as measured by a GFR ≤ 30ml/min per 1.73m2, measured ≤ 30 days prior to the procedure date Subject has a platelet count ≤ 50 or ≥ 600 X 103/µL ≤ 30 days prior to the procedure date NYHA class IV heart failure Subject has symptomatic coronary artery disease (ie, unstable angina) History of myocardial infarction or thrombolysis ≤ 90 days prior to the procedure date Non-atherosclerotic disease resulting in occlusion (eg, embolism, Buerger's disease, vasculitis) Subject is currently taking Canagliflozin Body Mass Index (BMI) <18 Active septicemia or bacteremia Coagulation disorder, including hypercoagulability Contraindication to anticoagulation or antiplatelet therapy Known allergies to stent or stent components Known allergy to contrast media that cannot be adequately pre-medicated prior to the interventional procedure Known hypersensitivity to heparin Subject is on a high dose of steroids or is on immunosuppressive therapy Subject is currently participating, or plans to participate in, another investigational trial that may confound the results of this trial (unless written approval is received from the Boston Scientific study team) Intra-procedure Exclusion Criteria Angiographic evidence of intra-arterial acute/subacute thrombus or presence of atheroembolism Treatment required in > 2 target vessels (Note: a target lesion originating in one vessel and extending into another vessel is considered 1 target vessel) Treatment requires the use of alternate therapy in the target vessel(s)/lesion(s), (eg, atherectomy, cutting balloon, re-entry devices, laser, radiation therapy) Aneurysm is present in the target vessel(s) Extremely calcified lesions

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Approximately 201 subjects will be randomized in a 2:1 fashion for phase A RCT. Randomizations will be stratified by investigational center and lesion length with 2 subjects receiving the DES BTK for every 1 subject receiving treatment with standard PTA.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: DES BTK<br>Treatment with DES BTK | Combination Product: Drug Eluting Stent - Below the Knee<br>* Treatment arm with DES-BTK, starting with one size of the device - 3.5 mm X 80 mm<br>|
| Active Comparator: Conventional PTA<br>Treatment with standard PTA | Device: Standard PTA Control Arm<br>* The PTA device used must be market-released in the investigational center's geography and the size (ie, diameter, balloon length and catheter length) will be determined by the investigator.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Primary Patency | Twelve-Month Primary Patency defined as a binary endpoint to be determined via duplex ultrasound (DUS) measuring flow at the 12-month follow-up visit, in the absence of clinically-driven target lesion revascularization (TLR) or bypass of the target lesion. Data table consists of the number of participants with flow as assessed by DUS. | 12 months | 
| Number of Participants Free From Major Adverse Events (MAE) | The primary safety endpoint assesses freedom from major adverse events (MAE) at 12 months post-procedure. (MAE is defined as: above ankle amputation in index limb; major re-intervention; and perioperative (30 day) mortality) | 12 months |