The THOR IDE Study (THOR)

March 18, 2026 updated by: Philips Clinical & Medical Affairs Global

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

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

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.

Study Type

Interventional

Enrollment (Estimated)

155

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • United States
    • California
      • St. Helena, California, United States, 94574
        • Recruiting
        • St. Helena Hospital
        • Contact:
        • Principal Investigator:
          • Leonardo Clavijo, MD
        • Contact:
        • Sub-Investigator:
          • Michael Gaglia, MD
    • Colorado
      • Aurora, Colorado, United States, 80045
        • Recruiting
        • Rocky Mountain Regional VA Medical Center
        • Contact:
        • Principal Investigator:
          • Bilal Aijaz, MD
        • Sub-Investigator:
          • Stephen Waldo, MD
        • Contact:
    • Florida
      • Bradenton, Florida, United States, 34205
      • Tallahassee, Florida, United States, 32308
        • Recruiting
        • Tallahassee Research Institute
        • Principal Investigator:
          • Andres Vargas, MD
        • Contact:
        • Contact:
        • Sub-Investigator:
          • John Katopodis
        • Sub-Investigator:
          • William Dixon
      • Winter Park, Florida, United States, 32792
        • Recruiting
        • Guardian Research Organization
        • Principal Investigator:
          • Ashish Gupta, MD
        • Contact:
        • Sub-Investigator:
          • Sandeep Bajaj
        • Contact:
          • Tiffany King
    • Iowa
      • Davenport, Iowa, United States, 52807
    • Louisiana
      • Houma, Louisiana, United States, 70360
        • Recruiting
        • Cardiovascular Institute of the South
        • Principal Investigator:
          • Craig Walker, MD
        • Sub-Investigator:
          • Matthew Finn, MD
        • Sub-Investigator:
          • Pradeep Nair, MD
        • Contact:
        • Contact:
        • Sub-Investigator:
          • McCall Walker, MD
      • Lafayette, Louisiana, United States, 70503
        • Recruiting
        • Cardiovascular Institute of the South
        • Principal Investigator:
          • Ankur Lodha, MD
        • Contact:
        • Sub-Investigator:
          • Amit Amin, MD
        • Sub-Investigator:
          • David Tadin, MD
    • Maine
      • Portland, Maine, United States, 04106
        • Recruiting
        • The Vascular Care Group
        • Sub-Investigator:
          • Todd Lancaster, MD
        • Sub-Investigator:
          • Daniel Gorin, MD
        • Sub-Investigator:
          • Christopher Kwolek, MD
        • Contact:
        • Contact:
        • Principal Investigator:
          • Nathan Aranson, MD
    • Massachusetts
      • Fall River, Massachusetts, United States, 02720
        • Recruiting
        • Southcoast Hospitals/Charlton Memorial Hospital
        • Principal Investigator:
          • Richard Pin, MD
        • Contact:
        • Sub-Investigator:
          • Mark Perry, MD
        • Contact:
        • Sub-Investigator:
          • Christopher Tanga, MD
      • Leominster, Massachusetts, United States, 04153
        • Recruiting
        • Vascular Breakthroughs
        • Sub-Investigator:
          • Sebastian DiDato, MD
        • Sub-Investigator:
          • Edward Arous, MD
        • Sub-Investigator:
          • Scott James, MD
        • Contact:
        • Principal Investigator:
          • Stephen Hoenig, MD
        • Sub-Investigator:
          • Paul Gagne, MD
        • Contact:
    • Michigan
      • Detroit, Michigan, United States, 48202
        • Recruiting
        • Henry Ford Hospital
        • Sub-Investigator:
          • Pedro Villablanca, MD
        • Sub-Investigator:
          • Khaldoon Alaswad, MD
        • Principal Investigator:
          • Herbert Aronow, MD
        • Contact:
        • Sub-Investigator:
          • Gerald Koenig, MD
        • Sub-Investigator:
          • Vikas Aggarwal, MD
        • Sub-Investigator:
          • Mohammad Alqarqaz, MD
        • Contact:
      • Detroit, Michigan, United States, 22201
        • Recruiting
        • Henry Ford St John Hospital
        • Contact:
        • Contact:
        • Principal Investigator:
          • Thomas Davis, Dr
    • New Jersey
      • Browns Mills, New Jersey, United States, 08015
        • Recruiting
        • Deborah Heart and Lung Center
        • Principal Investigator:
          • Richard Kovach, MD
        • Contact:
        • Contact:
        • Sub-Investigator:
          • Daniel Ice
        • Sub-Investigator:
          • Mohammad Raza, MD
      • New Brunswick, New Jersey, United States, 08901
      • Vineland, New Jersey, United States, 08360
        • Recruiting
        • Atlantic Medical Imaging of New jersey
        • Principal Investigator:
          • Micah Watts, MD
        • Contact:
        • Sub-Investigator:
          • Nicholas Petruzzi, MD
        • Contact:
    • New York
      • New York, New York, United States, 10029
        • Recruiting
        • Mount Sinai Hospital
        • Principal Investigator:
          • Prakash Krishnan, MD
        • Contact:
        • Sub-Investigator:
          • David Song, MD
        • Contact:
        • Sub-Investigator:
          • Vishal Kapur, MD
        • Sub-Investigator:
          • Raman Sharma
      • New York, New York, United States, 10029
        • Recruiting
        • New York Presbyterian Hospital/Columbia University Irving Medical Center
        • Contact:
        • Principal Investigator:
          • Virendra Patel, MD
        • Sub-Investigator:
          • Thomas O'Donnell, MD
        • Contact:
        • Sub-Investigator:
          • Nicholas Morrissey
        • Sub-Investigator:
          • Danielle Bajakian
    • North Carolina
      • Cary, North Carolina, United States, 27518
        • Recruiting
        • Vascular Solutions of North Carolina
        • Contact:
        • Principal Investigator:
          • Sid Rao, Dr.
        • Contact:
    • Ohio
      • Fairborn, Ohio, United States, 45324
        • Recruiting
        • Premier Cardiovascular Institute
        • Contact:
        • Principal Investigator:
          • Sagger Mawri, MD
        • Sub-Investigator:
          • James Pan, MD
        • Contact:
    • Oklahoma
      • Bartlesville, Oklahoma, United States, 74006
    • Pennsylvania
      • Mechanicsburg, Pennsylvania, United States, 17050
        • Recruiting
        • UPMC
        • Contact:
        • Principal Investigator:
          • William Bachinsky, Dr
        • Contact:
      • Philadelphia, Pennsylvania, United States, 19104
        • Recruiting
        • Hospital of the University of Pennsylvania
        • Contact:
        • Principal Investigator:
          • Elizabeth Genovese, MD
        • Sub-Investigator:
          • Shang Loh, MD
        • Sub-Investigator:
          • Alexander Fairman, MD
      • Wynnewood, Pennsylvania, United States, 19096
        • Recruiting
        • Lankenau Institute for Medical Research
        • Contact:
        • Principal Investigator:
          • Antonis Pratsos, MD
        • Sub-Investigator:
          • Manju Jayanna, MD
        • Sub-Investigator:
          • Sarang Mangalmurti, MD
        • Contact:
    • Rhode Island
      • Providence, Rhode Island, United States, 02905
        • Recruiting
        • The Miriam Hospital
        • Principal Investigator:
          • Peter Soukas, MD
        • Contact:
        • Sub-Investigator:
          • Pieter de Klerk, MD
    • Tennessee
      • Chattanooga, Tennessee, United States, 37421
        • Recruiting
        • Vascular Institute of Chattanooga
        • Contact:
        • Sub-Investigator:
          • William Harris, DO
        • Principal Investigator:
          • Chris LeSar, MD
    • Texas
      • Dallas, Texas, United States, 75390
      • Plano, Texas, United States, 75093
        • Recruiting
        • Baylor, Scott & White, The Heart Hospital
        • Principal Investigator:
          • Sameh Sayfo, MD
        • Sub-Investigator:
          • Chadi Dib, MD
        • Contact:
        • Sub-Investigator:
          • Tony Das, MD
        • Contact:
    • Virginia
      • Norfolk, Virginia, United States, 23507
        • Recruiting
        • Sentara Health Research Center
        • Principal Investigator:
          • David Dexter, MD
        • Contact:
        • Contact:
        • Sub-Investigator:
          • Animesh Rathore, MD
        • Sub-Investigator:
          • Priyam Vyas, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

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.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Thor Treatment
Treatment with the Thor system
Device: Thor laser atherectomy
Treatment of de novo calcified lesions with laser atherectomy and calcium modification using the Thor system
Other Names:
  • Thor calcium modification

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Procedural Success
Time Frame: At completion of the procedure
Defined as residual diameter stenosis ≤50% at the end of the procedure as determined by angiographic core lab
At completion of the procedure
Freedom from Major Adverse Events (MAEs)
Time Frame: 30 Days
Defined as freedom from MAEs including all-cause mortality, clinically driven target lesion revascularization (CD-TLR), unplanned target limb major amputation, perforations, flow-limiting dissections, and symptomatic distal embolizations that require an intervention to resolve
30 Days

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinically-driven target lesion revascularization
Time Frame: Through 12 months
Defined as repeat revascularization procedure of the target lesion if PSVR is ≥2.5 by DUS or if angiography shows a percent diameter stenosis >50% and there are worsening clinical symptoms, worsening Rutherford Clinical Category or ABI that is clearly referable to the target lesion.
Through 12 months
Technical success
Time Frame: Peri-procedural
Defined as the ability to deliver the Thor system and achieve residual diameter stenosis ≤50% after treatment with Thor and prior to adjunctive PTA, as confirmed by independent core laboratory assessments of angiographic images
Peri-procedural
Frequency of peri-procedural adverse events
Time Frame: Within 24 hours of the procedure
Defined as frequency of adverse events related to the investigational device (Thor system)
Within 24 hours of the procedure
Rutherford Classification change, 30 days
Time Frame: 30 days
Defined as the change in Rutherford classification at 30 days compared to the baseline (Screening) value. Rutherford Classification is a staging system to describe reduced blood flow in the lower limb. Rutherford Classifications values range from the least severe (asymptomatic) which is scored a 0 to the most severe (ulceration or gangrene) which is scored a 6.
30 days
Rutherford Classification change, 6 months
Time Frame: 6 months
Defined as the change in Rutherford classification at 6 months compared to the baseline (Screening) value. Rutherford Classification is a staging system to describe reduced blood flow in the lower limb. Rutherford Classifications values range from the least severe (asymptomatic) which is scored a 0 to the most severe (ulceration or gangrene) which is scored a 6.
6 months
Rutherford Classification change, 12 months
Time Frame: 12 months
Defined as the change in Rutherford classification at 12 months compared to the baseline (Screening) value. Rutherford Classification is a staging system to describe reduced blood flow in the lower limb. Rutherford Classifications values range from the least severe (asymptomatic) which is scored a 0 to the most severe (ulceration or gangrene) which is scored a 6.
12 months
Change in Short Form Health Survey (SF-36) score, 30 days
Time Frame: 30 days
Defined as the change in SF-36 score at 30 days compared to the baseline (Screening) value. The SF-36 is a patient-reported survey of patient health. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability. The higher the score the less disability i.e., a score of zero is equivalent to maximum disability and a score of 100 is equivalent to no disability.
30 days
Change in Short Form Health Survey (SF-36) score, 6 months
Time Frame: 6 months
Defined as the change in SF-36 score at 6 months compared to the baseline (Screening) value. The SF-36 is a patient-reported survey of patient health. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability. The higher the score the less disability i.e., a score of zero is equivalent to maximum disability and a score of 100 is equivalent to no disability.
6 months
Change in Short Form Health Survey (SF-36) score, 12 months
Time Frame: 12 months
Defined as the change in SF-36 score at 12 months compared to the baseline (Screening) value. The SF-36 is a patient-reported survey of patient health. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability. The higher the score the less disability i.e., a score of zero is equivalent to maximum disability and a score of 100 is equivalent to no disability.
12 months
Change in Walking Impairment Questionnaire (WIQ) score, 30 days
Time Frame: 30 days
Defined as the change in WIQ score at 30 days compared to the baseline (Screening) value. The WIQ measures self-reported walking impairment, walking distance, walking speed, and stair-climbing ability. In the WIQ there are 21 questions to rate the degree of difficulty with the walking and stair climbing elements. The response for each question is on a 0 to 4 scale, where 0 represents the inability to walk or climb stairs, and 4 represents no difficulty.
30 days
Change in Walking Impairment Questionnaire (WIQ) score, 6 months
Time Frame: 6 months
Defined as the change in WIQ score at 6 months compared to the baseline (Screening) value. The WIQ measures self-reported walking impairment, walking distance, walking speed, and stair-climbing ability. In the WIQ there are 21 questions to rate the degree of difficulty with the walking and stair climbing elements. The response for each question is on a 0 to 4 scale, where 0 represents the inability to walk or climb stairs, and 4 represents no difficulty.
6 months
Change in Walking Impairment Questionnaire (WIQ) score, 12 months
Time Frame: 12 months
Defined as the change in WIQ score at 12 months compared to the baseline (Screening) value. The WIQ measures self-reported walking impairment, walking distance, walking speed, and stair-climbing ability. In the WIQ there are 21 questions to rate the degree of difficulty with the walking and stair climbing elements. The response for each question is on a 0 to 4 scale, where 0 represents the inability to walk or climb stairs, and 4 represents no difficulty.
12 months
Target Limb Ankle-Brachial Index (ABI) change, Discharge
Time Frame: Discharge or up to 24 hours after the procedure
Defined as the change in blood pressure in the upper limb (arm) and lower limb (leg or toes) at discharge compared to the baseline (Screening) value
Discharge or up to 24 hours after the procedure
Target Limb Ankle-Brachial Index (ABI) change, 30 days
Time Frame: 30 days
Defined as the change in blood pressure in the upper limb (arm) and lower limb (leg or toes) at 30 days compared to the baseline (Screening) value
30 days
Target Limb Ankle-Brachial Index (ABI) change, 6 months
Time Frame: 6 months
Defined as the change in blood pressure in the upper limb (arm) and lower limb (leg or toes) at 6 months compared to the baseline (Screening) value
6 months
Target Limb Ankle-Brachial Index (ABI) change, 12 months
Time Frame: 12 months
Defined as the change in blood pressure in the upper limb (arm) and lower limb (leg or toes) at 12 months compared to the baseline (Screening) value
12 months
Target lesion patency, 30 days
Time Frame: 30 days
Defined as freedom from CD-TLR and freedom from ≥50% restenosis as determined by duplex ultrasound (DUS) or angiogram
30 days
Target lesion patency, 6 months
Time Frame: 6 months
Defined as freedom from CD-TLR and freedom from ≥50% restenosis as determined by duplex ultrasound (DUS) or angiogram
6 months
Target lesion patency, 12 months
Time Frame: 12 months
Defined as freedom from CD-TLR and freedom from ≥50% restenosis as determined by duplex ultrasound (DUS) or angiogram
12 months
Adjunctive devices used with the Thor system
Time Frame: Peri-procedural
Defined as the use of other devices including angioplasty balloons, drug coated balloons, bailout stents, embolic filters
Peri-procedural
Freedom from Major Adverse Events (MAEs)
Time Frame: Through 12 months
Defined as freedom from MAEs including all-cause mortality, clinically driven target lesion revascularization (CD-TLR), unplanned target limb major amputation, and perforations, flow-limiting dissections, and symptomatic distal embolizations that require an intervention to resolve
Through 12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Philips Clinical & Medical Affairs Global

Collaborators

NAMSA
Syntropic Corelab

Investigators

  • Principal Investigator: Elizabeth Genovese, MD, University of Pennsylvania
  • Principal Investigator: Pradeep Nair, MD, Cardiovascular Institute of the South (CIS)

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 29, 2024

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 1, 2027

Study Registration Dates

First Submitted

June 7, 2023

First Submitted That Met QC Criteria

June 14, 2023

First Posted (Actual)

June 23, 2023

Study Record Updates

Last Update Posted (Actual)

March 20, 2026

Last Update Submitted That Met QC Criteria

March 18, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 200201

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Peripheral Artery Disease

Clinical Trials on Thor laser atherectomy

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Lebanon

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe