The THOR IDE Study

Overview

The goal of this clinical trial is to test the Thor system in adult (≥ 18 year old) patients with de novo (new, never treated) calcified lesions in infrainguinal (leg) arteries (peripheral artery disease or PAD). The main question\[s\] it aims to answer are: * Is the Thor system safe in treating these lesions * Does the Thor system work to treat these lesions Participants will: * Receive treatment with the Thor system * Have follow-up visits at Discharge, 30 days, 6 months, and 12 months

Detailed description

Up to 30 sites in the U.S. will be selected to do this study.

Patients with pain in their legs when walking and/or resting that is due to lack of blood flow to their legs may be able to join the study. To join the study patients must also have blockages in their leg arteries that meet the study criteria.

Before the Thor procedure, patients will have a screening visit that includes a review of their medical records, questions about their medical history and medications taken for blood thinning or circulation, a physical examination of their legs, a test to check the blood flow in their legs (by checking arm and leg blood pressures), blood tests, and a pregnancy test if they are a female able to have children. Patients will also answer questions about any trouble they have had with walking in the last week and their overall quality of life.

All patients in the study will have treatment with the Thor system. There is no "control group" (a group of patients that receives only standard treatment or receives no treatment at all) in this study. During the procedure, the doctor will take x-ray pictures of the leg arteries. They may also use other treatments such as angioplasty balloons, drug-coated balloons, stents, and filters that collect blood clots, if needed.

Patients treated with the Thor system will be watched until they are ready to go home or up to 24 hours after the procedure if they do not go home right away. Before they go home they will have a test to check the blood flow to their legs (by checking arm and leg blood pressures) and be checked for any adverse events.

Patients will return for visits at 30 days, 6 months, and 12 months after the Thor procedure. At these visits patients will be asked questions about their medical history and medications taken for blood thinning or circulation, have a physical examination of their legs, have a test to check the blood flow in their treated leg (by checking arm and leg blood pressures), have an ultrasound of their treated leg, and be checked for any adverse events. Patients will also answer questions about any trouble they have had with walking in the last week and their overall quality of life.

It will take up to 24 months (2 years) to enroll all of the patients in the study. Patients who join the study will be in the study for about 12 months (1 year) and will have all of the visits with their doctor that they would normally have for their PAD.

Interventions

• Device Thor laser atherectomy
  Treatment of de novo calcified lesions with laser atherectomy and calcium modification using the Thor system

Primary outcome measures

• Freedom from Major Adverse Events (MAEs) [Time frame: 30 Days]
• Procedural Success [Time frame: At completion of the procedure]

Secondary outcome measures (12)

• Target lesion patency, 30 days [Time frame: 30 days]
• Target lesion patency, 6 months [Time frame: 6 months]
• Target lesion patency, 12 months [Time frame: 12 months]
• Clinically-driven target lesion revascularization [Time frame: Through 12 months]
• Technical success [Time frame: Peri-procedural]
• Frequency of peri-procedural adverse events [Time frame: Within 24 hours of the procedure]
• Adjunctive devices used with the Thor system [Time frame: Peri-procedural]
• Target Limb Ankle-Brachial Index (ABI) change, Discharge [Time frame: Discharge or up to 24 hours after the procedure]
• Target Limb Ankle-Brachial Index (ABI) change, 30 days [Time frame: 30 days]
• Target Limb Ankle-Brachial Index (ABI) change, 6 months [Time frame: 6 months]
• Target Limb Ankle-Brachial Index (ABI) change, 12 months [Time frame: 12 months]
• Rutherford Classification change, 30 days [Time frame: 30 days]

Eligibility criteria

Inclusion criteria

• Patient age is ≥18 years
• Patient agrees to participate and to comply with the protocol by signing an IRB approved patient consent form
• Patient is able to walk unassisted or with non-motorized assistive devices
• Patient has PAD with documented Rutherford Class 2-4 of the target limb
• Anticipated life expectancy >12 months, in the opinion of the investigator at the time of enrollment.

Angiographic Inclusion Criteria:

• Patient has de novo atherosclerotic disease of the native SFA and/or the popliteal arteries
• Target lesion has ≥70% diameter stenosis by investigator via visual assessment
• Target lesion length ≤150mm. Total treatment zone may not exceed 150mm, and may include one or more lesions.
• Chronic total occlusion lesion length is <100mm of the total ≤150mm target lesion
• Minimum reference vessel diameter (RVD) 4.0mm by visual estimate
• Target lesion crossed and intraluminal guidewire placement confirmed; successful crossing defined as tip of the guidewire distal to the target lesion in the absence of flow limiting dissections or perforations
• At least one patent tibial vessel (defined as <50% stenosis) with runoff to the foot
• Target lesion has moderate to severe calcification graded using the Peripheral Academic Research Consortium (PARC) criteria

Exclusion criteria

• Patient has active infection requiring antibiotic therapy
• Stenting planned within the target lesion
• Known positive for COVID-19 within the last 2 weeks and actively symptomatic
• Pregnant (positive pregnancy test) or currently breast feeding
• Evidence of Acute Limb Ischemia in the target limb within 7 days prior to procedure
• Cerebrovascular accident (CVA) <60 days prior to procedure
• Myocardial infarction <60 days prior to procedure
• History of unstable coronary artery disease or other uncontrollable comorbidity resulting in hospitalization within the last 60 days prior to baseline screening
• Known contraindication to aspirin, or antiplatelet/anti-coagulant therapies required for procedure/follow-up
• Known allergy to contrast media that cannot adequately be premedicated prior to study procedure
• History of Thrombophilia, Heparin-induced Thrombocytopenia (HIT), or Heparin-induced Thrombotic Thrombocytopenia Syndrome (HITTS)
• Serum creatinine ≥2.5mg/dL (unless dialysis-dependent) tested within 30 days prior to procedure
• Planned lower limb major amputation (above the ankle)
• Other surgical or endovascular procedure in the target limb that occurred within 14 days prior to index procedure or is planned on target limb for within 30 days following index procedure, with the exception of diagnostic angiography
• Currently participating in any investigational device or drug clinical trial that, in the opinion of the investigator, will interfere with the conduct of the current study
• The use of specialty balloons, re-entry or additional atherectomy devices is required for treatment of the target lesion.

Angiographic Exclusion Criteria:

• Subject has significant stenosis (>50% stenosis) or occlusion of inflow tract before target treatment zone (e.g. iliac or common femoral) not successfully treated.
• Subject requires treatment of a peripheral lesion on the ipsilateral limb distal to the target site at the time of the index procedure.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Treatment

Study locations

United States · 29 centers

• St. Helena Hospital — St. Helena
• Rocky Mountain Regional VA Medical Center — Aurora
• Manatee Memorial Hospital — Bradenton
• Tallahassee Research Institute — Tallahassee
• Guardian Research Organization — Winter Park
• Vascular Institute of the Midwest — Davenport
• Cardiovascular Institute of the South — Houma
• Cardiovascular Institute of the South — Lafayette
• … and 21 more centers

Publications

• Norgren L, Hiatt WR, Dormandy JA, Nehler MR, Harris KA, Fowkes FG; TASC II Working Group; Bell K, Caporusso J, Durand-Zaleski I, Komori K, Lammer J, Liapis C, Novo S, Razavi M, Robbs J, Schaper N, Shigematsu H, Sapoval M, White C, White J, Clement D, Creager M, Jaff M, Mohler E 3rd, Rutherford RB, Sheehan P, Sillesen H, Rosenfield K. Inter-Society Consensus for the Management of Peripheral Arteria PMID 17140820
• Hirsch AT, Haskal ZJ, Hertzer NR, Bakal CW, Creager MA, Halperin JL, Hiratzka LF, Murphy WR, Olin JW, Puschett JB, Rosenfield KA, Sacks D, Stanley JC, Taylor LM Jr, White CJ, White J, White RA, Antman EM, Smith SC Jr, Adams CD, Anderson JL, Faxon DP, Fuster V, Gibbons RJ, Hunt SA, Jacobs AK, Nishimura R, Ornato JP, Page RL, Riegel B; American Association for Vascular Surgery; Society for Vascular PMID 16549646
• Hirsch AT, Criqui MH, Treat-Jacobson D, Regensteiner JG, Creager MA, Olin JW, Krook SH, Hunninghake DB, Comerota AJ, Walsh ME, McDermott MM, Hiatt WR. Peripheral arterial disease detection, awareness, and treatment in primary care. JAMA. 2001 Sep 19;286(11):1317-24. doi: 10.1001/jama.286.11.1317. PMID 11560536
• Mueller T, Hinterreiter F, Poelz W, Haltmayer M, Dieplinger B. Mortality rates at 10 years are higher in diabetic than in non-diabetic patients with chronic lower extremity peripheral arterial disease. Vasc Med. 2016 Oct;21(5):445-452. doi: 10.1177/1358863X16643603. Epub 2016 Apr 11. PMID 27067137
• Caro J, Migliaccio-Walle K, Ishak KJ, Proskorovsky I. The morbidity and mortality following a diagnosis of peripheral arterial disease: long-term follow-up of a large database. BMC Cardiovasc Disord. 2005 Jun 22;5:14. doi: 10.1186/1471-2261-5-14. PMID 15972099
• Dieter RS, Chu WW, Pacanowski JP Jr, McBride PE, Tanke TE. The significance of lower extremity peripheral arterial disease. Clin Cardiol. 2002 Jan;25(1):3-10. doi: 10.1002/clc.4950250103. PMID 11808837
• Guez D, Hansberry DR, Gonsalves CF, Eschelman DJ, Parker L, Rao VM, Levin DC. Recent Trends in Endovascular and Surgical Treatment of Peripheral Arterial Disease in the Medicare Population. AJR Am J Roentgenol. 2020 May;214(5):962-966. doi: 10.2214/AJR.19.21967. Epub 2020 Feb 25. PMID 32097027
• Rocha-Singh KJ, Jaff MR, Crabtree TR, Bloch DA, Ansel G; VIVA Physicians, Inc. Performance goals and endpoint assessments for clinical trials of femoropopliteal bare nitinol stents in patients with symptomatic peripheral arterial disease. Catheter Cardiovasc Interv. 2007 May 1;69(6):910-9. doi: 10.1002/ccd.21104. PMID 17377972

Identifiers

NCT: NCT05916950 · 200201

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗