Far Red Light to Improve Functioning in PAD

NCT06165016 | Recruiting

• 1 other identifier: STU00218660
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 2

Brief Summary

The LIGHT PAD Trial is a Phase II multi-centered randomized clinical trial to collect preliminary data to test whether daily far red light treatment of the lower extremities in people with PAD improves six-minute walk distance, lower extremity perfusion, and ischemia-related damage in gastrocnemius muscle at four-month follow-up, compared to a sham control. Participants will complete 10 minutes of twice daily home treatment with either far red light or a sham light for four months.

Conditions

Peripheral Artery Disease; Peripheral Vascular Disease; Aging; Walking, Difficulty

Keywords

light therapy

Outcome Measures

Primary Outcomes (1)

• Six-Minute Walk Distance

  Four month change in six-minute walk distance

  Measured at baseline and 4 month follow-up

Secondary Outcomes (4)

• Walking Impairment Questionnaire Distance (WIQ) Score

  Measured at baseline and 4 month follow-up

• Six-Minute Walk Distance

  Measured immediately after the first light treatment (within 15 minutes after the first treatment, acute effect)

• Six-minute walk distance.

  Measured at 4-month follow-up, 24 hours after the final treatment.

• Calf muscle perfusion

  Measured at baseline and four-month follow up

Other Outcomes (11)

• Plasma nitrite

  Measured before and within five minutes after the first light treatment

• Plasma nitrite

  Measured before and within five minutes after the final light treatment at four-month follow up

• Plasma Nitrosothiols

  Measured before and within five minutes after the first light treatment

Study Arms (2)

Far red light therapy

EXPERIMENTAL

Subgroup of participants receiving the 670 nm far red light device

Device: Far red light therapy

Sham therapy

SHAM COMPARATOR

Subgroup of participants receiving the sham light device, far red light device covered with blue filter paper to block 670 nm light, resulting in mean power generated of 0.24 mW/cm2, compared to 26.3 mW/cm2 for the intervention, a 100-fold difference.

Device: Sham light therapy

Interventions

Far red light therapy DEVICE

All participants will receive one far red light device per leg. Participants will be asked to use their two light devices daily, exposing their bare legs to the devices for 10 minutes twice per day. A study coordinator will deliver the light devices to each participant's home, positioning the devices 15 cm behind the participant's heels, using tape on the floor to mark where the light and feet should be positioned. Twice each day, the participant flips a switch on the device to begin each session. A timer will turn off the device after 10 minutes. A power meter will measure the total time that the device was turned on. Participants will also record use of the light in a log.

Far red light therapy

Sham light therapy DEVICE

All participants will receive one sham device per leg. Participants will be asked to use their two light devices daily, exposing their bare legs to the devices for 10 minutes twice per day. A study coordinator will deliver the light devices to each participant's home, positioning the devices 15 cm behind the participant's heels, using tape on the floor to mark where the light and feet should be positioned. Twice each day, the participant flips a switch on the device to begin each session. A timer will turn off the device after 10 minutes. A power meter will measure the total time that the device was turned on. Participants will also record use of the light in a log.

Sham therapy

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• First, all participants will be age 50 and older. Second, all participants will have PAD. PAD will be defined as:
• An ABI \<= 0.90 at baseline.
• Vascular lab evidence of PAD (such as a toe brachial pressure =\< 0.70 or an ankle brachial index less than or equal to 0.90), or angiographic evidence of PAD defined as at least 70% stenosis of an artery supplying the lower extremities.
• An ABI of \>0.90 and \<= 1.00 who experience a 20% or greater drop in ABI in either leg after the heel-rise test.

You may not qualify if:

• Above- or below-knee amputation
• Critical limb ischemia defined as an ABI \<0.40 with symptoms of rest pain
• Wheelchair confinement or requiring a walker to ambulate
• Walking is limited by a symptom other than PAD
• Current foot ulcer on bottom of foot
• Failure to successfully complete the study run-in
• Planned major surgery, coronary or leg revascularization during the next four months
• Major surgery, coronary or leg revascularization or major cardiovascular event in the previous three months
• Major medical illness including lung disease requiring oxygen, Parkinson's disease, a life-threatening illness with life expectancy less than six months, or cancer requiring treatment in the previous two years. \[NOTE: potential participants may still qualify if they have had treatment for an early stage cancer in the past two years and the prognosis is excellent, unless the cancer is located in the lower extremities. Participants who require oxygen only at night may still qualify.\]
• Mini-Mental Status Examination (MMSE) score \< 23
• Non-English speaking
• Participation in or completion of a clinical trial in the previous three months. \[NOTE: after completing a stem cell or gene therapy intervention, participants will become eligible after the final study follow-up visit of the stem cell or gene therapy study so long as at least six months have passed since the final intervention administration. After completing a supplement or drug therapy (other than stem cell or gene therapy), participants will be eligible after the final study follow-up visit as long as at least three months have passed since the final intervention of the trial.\]
• Visual impairment that limits walking ability.
• Six-minute walk distance of \<400 feet or \>1700 feet.
• Participation in a supervised treadmill exercise program or a cardiac rehabilitation program in previous three months or planning to begin a supervised treadmill exercise program or a cardiac rehabilitation program in the next five months.

Sponsors & Collaborators

• Northwestern University: lead

Study Sites (2)

University of Alabama at Birmingham

Birmingham, Alabama, 35294, United States

RECRUITING

Northwestern University

Chicago, Illinois, 60611, United States

RECRUITING

MeSH Terms

Conditions

Peripheral Arterial Disease; Peripheral Vascular Diseases; Mobility Limitation

Condition Hierarchy (Ancestors)

Atherosclerosis; Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases; Cardiovascular Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Mary McDermott, MD

CONTACT

13125036419; mdm608@northwestern.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Masking Details: This will be a double blinded study where both the participant and the people collecting data will be blinded.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Jeremiah Stamler Professor of Medicine

Model Details: Investigators will randomize 32 participants age 50 and older with PAD to one of two groups: far red light therapy or sham therapy. Participants will be followed for four months.

Study Record Dates

• First Submitted: November 19, 2023
• First Posted: December 11, 2023
• Study Start: February 14, 2024
• Primary Completion (Estimated): January 30, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: August 26, 2025

Record last verified: 2025-08

Locations

US (2)