NCT06399900 · Northwestern University
ENhancing Exercise With LIGHT to Improve Functioning in PAD
(ENLIGHTEN PAD)
What this study is about
The ENLIGHTEN PAD Trial will collect preliminary data to test whether daily 660 nm light treatment of the lower extremities immediately before home-based walking exercise sessions improves six-minute walk distance at 4-month follow-up, compared to sham light, in people with lower extremity peripheral artery disease (PAD).
View original scientific description
The ENLIGHTEN PAD Trial will collect preliminary data to test whether daily 660 nm light treatment of the lower extremities immediately before home-based walking exercise sessions improves six-minute walk distance at 4-month follow-up, compared to sham light, in people with lower extremity peripheral artery disease (PAD).
Interventions
DEVICE
Far red light therapy
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. An unblinded 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.
DEVICE
Sham light therapy
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. An unblinded 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.
BEHAVIORAL
Home-based walking exercise
This study involves a 16 week intervention where participants will walk at home for exercise with guidance from a study coach. Participants will have 4 in-person visits in the first four weeks and then have weekly phone calls in the last 12 weeks of the intervention with their coach.
Primary outcome measures
Six-Minute Walk Distance
Time frame: Measured at baseline and 4-month follow-up
Change in six-minute walk distance
Six-Minute Walk Distance
Time frame: Measured immediately after the first light treatment (within 15 minutes after the first treatment, acute effect)
Change in six-minute walk distance (acute effect)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- 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.
Exclusion criteria
- 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.
- Unwilling to avoid red light therapy outside of study participation.
- Baseline blood pressure \<100/45.
- In addition to the above criteria, investigator discretion will be used to determine if the trial is unsafe or not a good fit for the potential participant.
Where
- Chicago, Illinois
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 15, 2026 · Source of record for eligibility and locations