Light Therapy and Exercise for PAD

(ENLIGHTEN PAD Trial)

Overseen By Kathryn Domanchuk

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Northwestern University

Disqualifiers: Amputation, Critical limb ischemia, Wheelchair, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 16 weeks

32 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether using red light therapy (also known as Far Red Light Therapy) on the legs before walking exercises can help individuals with peripheral artery disease (PAD) walk longer distances after four months. Participants will use either the real red light device or a sham device that looks identical but does not emit the effective light. The goal is to determine if the real light treatment enhances exercise benefits more than the sham. The trial seeks participants aged 50 and older who have been diagnosed with PAD and experience symptoms like leg pain when walking. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could improve walking ability for those with PAD.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that this light therapy and exercise protocol is safe for people with PAD?

Previous studies have shown that far red light therapy is well-tolerated. Research suggests it can improve blood flow by increasing nitric oxide levels, potentially benefiting people with peripheral artery disease (PAD). These studies have reported no major side effects, indicating promising safety.

Conversely, home-based walking exercise is a safe and common method to enhance walking endurance in people with PAD. Studies have demonstrated that it improves walking ability without significant side effects.

Both treatments in this trial have shown positive safety profiles in past research, suggesting they are likely to be well-tolerated by participants. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Unlike standard treatments for Peripheral Artery Disease (PAD), which typically involve medications like statins and antiplatelet drugs, Far Red Light Therapy offers a non-invasive alternative. This therapy uses a specific wavelength of light (670 nm) that may improve blood flow and promote tissue repair, targeting the underlying issues of reduced circulation in PAD patients. Researchers are excited because this approach could enhance exercise capacity and reduce symptoms without the side effects associated with traditional medications. Additionally, combining this light therapy with home-based walking exercises represents an innovative, patient-friendly treatment strategy that empowers individuals to manage their condition effectively at home.

What evidence suggests that this trial's treatments could be effective for PAD?

Research has shown that far red light therapy, one of the treatments in this trial, can improve blood flow in people with peripheral artery disease (PAD). Studies have found that this therapy increases certain compounds in the blood that widen blood vessels, enhancing blood flow and leg movement. Additionally, far red light therapy encourages the growth of new blood vessels, boosting circulation in affected areas. This trial will compare the effects of combining far red light therapy with home-based walking exercises to a sham therapy with walking exercises, to determine if these interventions help people with PAD walk farther and move more easily. ^{1 2 3 4 5}

Are You a Good Fit for This Trial?

This trial is for individuals with peripheral artery disease (PAD), which often causes difficulty walking and limited mobility due to poor blood flow in the legs. Participants should be able to perform home-based exercises and have no conditions that would interfere with light therapy.

Inclusion Criteria

I am 50 years old or older.

I have been diagnosed with PAD based on specific tests.

Exclusion Criteria

I have a current foot ulcer on the bottom of my foot.

I use a wheelchair or walker to move around.

Failure to successfully complete the study run-in

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive daily 660 nm light treatment of the lower extremities immediately before home-based walking exercise sessions

16 weeks

Daily sessions (home-based)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Far Red Light Therapy
• Home-based walking exercise

Trial Overview The ENLIGHTEN PAD Trial is testing if shining a special red light on the lower legs before walking exercises can improve walking distance after four months, compared to using a fake light treatment in people with PAD.

How Is the Trial Designed?

Group I: Far red light therapy + home-based walking exercise Experimental Treatment 2 Interventions

Subgroup of participants receiving home-based walking exercise and the 670 nm far red light device

Group II: Sham therapy + home-based walking exercise Placebo Group 2 Interventions

Subgroup of participants receiving home-based walking exercise and 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.

Far Red Light Therapy is already approved in United States for the following indications:

Approved in United States as Red Light Therapy for:

• Pain relief
• Muscle and joint aches
• Arthritis pain and stiffness
• Tendinitis pain

Who Is Running the Clinical Trial?

Northwestern University

Lead Sponsor

Trials

1,674

Recruited

989,000+

Published Research Related to This Trial

Photobiomodulation therapy, which includes low-level laser therapy and light-emitting diodes, has gained significant attention over the past decade for its potential to enhance athletic performance and accelerate post-exercise recovery, as supported by recent systematic reviews and randomized controlled trials.

The article emphasizes the importance of establishing clinical and scientific recommendations based on high-quality evidence to guide the proper use of photobiomodulation therapy, ensuring that future studies avoid relying on less rigorous data such as animal experiments or anecdotal case studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical and scientific recommendations for the use of photobiomodulation therapy in exercise performance enhancement and post-exercise recovery: current evidence and future directions. Leal-Junior, ECP., Lopes-Martins, RÁB., Bjordal, JM.[2022]

Photobiomodulation therapy (PBMT) using red and near-infrared light is more effective for promoting keratinocyte activity compared to blue light, with optimal results typically occurring at energy densities between 0.1-5.0 J/cm2.

Higher energy densities above 15.0 J/cm2 were found to be ineffective or even harmful, leading to cell death, highlighting the importance of proper light dosimetry in PBMT applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Photobiomodulation effects on keratinocytes cultured in vitro: a critical review. de Abreu, PTR., de Arruda, JAA., Mesquita, RA., et al.[2020]

Low level light therapy (LLLT) using specific wavelengths of LED light (633 nm and 830 nm) has been shown to effectively enhance wound healing and reduce pain and inflammation, supported by both animal and human studies.

LED-LLLT can significantly improve outcomes for non-healing wounds and accelerate healing in normal wounds, making it a promising adjunct treatment alongside traditional surgical and nonsurgical methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Is light-emitting diode phototherapy (LED-LLLT) really effective? Kim, WS., Calderhead, RG.[2022]

Photobiomodulation therapy, or laser therapy, uses red and near-infrared light to promote healing, alleviate pain, and decrease inflammation in veterinary medicine.

While there is growing evidence supporting its effectiveness for certain conditions, the results are mixed or limited for others, indicating that more research is needed to fully understand its applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Photobiomodulation (Therapeutic Lasers): An Update and Review of Current Literature. Bunch, J.[2023]

Low-level laser therapy (LLLT) effectively reduces pain and promotes healing by using coherent light in the 600 to 1000 nm wavelength range, which triggers biochemical changes in cells and has been supported by numerous clinical and experimental studies.

LLLT has shown significant analgesic and anti-inflammatory effects, making it a promising complementary treatment option for managing symptoms in patients with osteoarthritis and chronic pain.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Review of Literature on Low-level Laser Therapy Benefits for Nonpharmacological Pain Control in Chronic Pain and Osteoarthritis. Dima, R., Tieppo Francio, V., Towery, C., et al.[2019]

Low-level light therapy (LLLT) has been shown to be a safe and effective treatment for skin rejuvenation, acne vulgaris, and body contouring, supported by a reasonable amount of clinical trial evidence.

Despite its commercial success, the quality of evidence for LLLT is limited by methodological flaws and small sample sizes, highlighting the need for more rigorous, independent clinical trials to validate its therapeutic benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Photobiomodulation: The Clinical Applications of Low-Level Light Therapy. Glass, GE.[2022]

Low-level light therapy (photobiomodulation) shows promising benefits in periodontal and dental implant treatments, including enhanced healing and reduced inflammation, based on a review of various studies.

Despite the positive effects observed, there is significant variability in study designs and light irradiation parameters, making it difficult to establish standardized evidence-based treatment protocols for clinical practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Photobiomodulation in Periodontology and Implant Dentistry: Part 2. Gholami, L., Asefi, S., Hooshyarfard, A., et al.[2020]

Low Level Laser Therapy (LLLT) has shown potential in improving wound healing and reducing pain, inflammation, and swelling, with mechanisms of action observed at both cellular and tissue levels.

LLLT may soon be applicable to serious conditions like stroke and traumatic brain injury, as the field expands to include various light sources and wavelengths, supported by randomized controlled clinical trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The nuts and bolts of low-level laser (light) therapy. Chung, H., Dai, T., Sharma, SK., et al.[2022]

Photobiomodulation, or light therapy using low-energy red lasers, shows promise for treating a variety of medical conditions, including neurological issues like stroke and traumatic brain injury, as well as pain management and skin conditions.

The mechanisms of action for photobiomodulation are still not fully understood, but research indicates that red lasers can penetrate the skull, suggesting potential therapeutic effects on brain function.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Perspective on Broad-Acting Clinical Physiological Effects of Photobiomodulation. Shanks, S., Leisman, G.[2019]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9108481/

In Vivo Characterization of a Red Light-Activated Vasodilation Our results strongly support 670 nm light can regulate dilation of conduit vessel by releasing a vasoactive nitric oxide precursor species.

2. clinicaltrials.gov clinicaltrials.gov/study/NCT06165016

NCT06165016 | Far Red Light to Improve Functioning in PAD 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 ...

3. withpower.com withpower.com/trial/phase-2-walking-difficulty-2024-a26a0

Far Red Light Therapy for Peripheral Arterial Disease Far Red Light Therapy, also known as low-level laser therapy ... What data supports the effectiveness of Far Red Light Therapy for Peripheral Arterial Disease?

4. scholars.northwestern.edu scholars.northwestern.edu/en/projects/proprioception-and-joint-stability-across-planes-in-knee-asteoart-7

Far Red Light to Improve Functioning in PAD A single dose of far red light therapy increased plasma nitrosothiols, improved lower extremity blood flow, and meaningfully improved functional performance in ...

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3747970/

Far Red/Near Infrared Light Treatment Promotes Femoral ... R/NIR increases NO levels independent of NOS activity, and leads to the observed enhancement of hindlimb collateralization.