Far Red Light Therapy for Peripheral Arterial Disease

(LIGHT PAD Trial)

Recruiting at 1 trial location

Overseen By Mary McDermott, MD

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)

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 tests whether far red light therapy, a type of phototherapy, can help individuals with Peripheral Arterial Disease (PAD) walk longer distances and improve blood flow in their legs. Participants will use a special light device on their legs twice daily for four months. Individuals with PAD who experience difficulty walking due to leg pain might be suitable for this trial. As an unphased trial, it offers participants the chance to explore a novel therapy that could potentially enhance their quality of life.

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 is best to discuss this with the trial coordinators or your doctor.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that far red light therapy is generally safe. Studies have found that this treatment can aid healing and reduce inflammation, the body's response to injury. Although the exact mechanism remains unclear, the therapy has improved blood flow in the lower body.

Additionally, far red light therapy can increase certain substances in the blood that aid circulation. These findings suggest the treatment is well-tolerated and safe for individuals.

Overall, far red light therapy appears promising, with few safety concerns reported in previous studies. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about Far Red Light Therapy for Peripheral Arterial Disease because it offers a non-invasive and potentially safer alternative to current treatments like medications or surgical interventions. Unlike standard treatments that focus on improving blood flow through medication or surgery, Far Red Light Therapy uses a specific wavelength of light (670 nm) to stimulate cellular processes and improve blood circulation. This novel approach could reduce side effects and recovery time, making it an attractive option for patients seeking less invasive treatment. If effective, this therapy might provide quicker relief and enhance the quality of life for those with peripheral arterial disease.

What evidence suggests that far red light therapy might be an effective treatment for peripheral arterial disease?

Research has shown that far red light therapy, a treatment under study in this trial, might benefit people with Peripheral Arterial Disease (PAD). Studies have found that this therapy can increase nitric oxide levels in the blood. Nitric oxide widens blood vessels, improving blood flow. In some tests, far red light therapy improved leg blood flow and made walking easier. Early results also suggest it might reduce muscle damage. These findings support the idea that far red light therapy could ease symptoms for PAD patients. ^{1 2 3 4 5}

Are You a Good Fit for This Trial?

This trial is for people over 50 with Peripheral Arterial Disease (PAD), evidenced by specific tests. They must be able to walk without a walker or wheelchair, not have critical limb ischemia, recent major surgeries, severe medical conditions like advanced lung disease or Parkinson's, and should not be in another clinical trial recently.

Inclusion Criteria

I am 50 years old or older.

I have been diagnosed with PAD based on specific tests and criteria.

Exclusion Criteria

I haven't had major surgery or significant heart issues in the last 3 months.

My walking is limited by a condition that is not related to leg artery disease.

I am scheduled for major surgery or heart/leg artery treatment in the next 4 months.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive daily far red light treatment or sham control for four months

16 weeks

Home treatment, twice daily

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
• Sham Light Therapy

Trial Overview The LIGHT PAD Trial is testing if far red light therapy can improve walking distance and blood flow in the legs of PAD patients compared to a fake light treatment. Participants will use the assigned light device on their lower extremities at home for ten minutes twice daily over four months.

How Is the Trial Designed?

Group I: Far red light therapy Experimental Treatment 1 Intervention

Subgroup of participants receiving the 670 nm far red light device

Group II: Sham therapy Placebo Group 1 Intervention

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.

Who Is Running the Clinical Trial?

Northwestern University

Lead Sponsor

Trials

1,674

Recruited

989,000+

Published Research Related to This Trial

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) significantly increased nitric oxide (NO) levels in the venous blood of 15 healthy subjects, indicating its potential efficacy in enhancing blood flow.

The peak increase in NO occurred 5 minutes after treatment, suggesting that LLLT may be effective shortly after application, although further studies are needed to evaluate its effects in patients with medical conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low-level laser treatment with near-infrared light increases venous nitric oxide levels acutely: a single-blind, randomized clinical trial of efficacy. Mitchell, UH., Mack, GL.[2016]

In a study involving 48 male cyclists, the combination of infrared and red photobiomodulation therapy showed a significant positive effect on performance metrics like total time to exhaustion and VO2max, suggesting that using both wavelengths together may enhance athletic performance.

While no significant differences were found in most performance measures, moderate to large effect sizes were observed in specific areas, indicating that while PBMT alone may not improve performance, the combination of wavelengths could be beneficial when applied correctly.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Photobiomodulation by light emitting diode applied sequentially does not alter performance in cycling athletes. de Carvalho, G., Gobbi, A., Gobbi, RB., et al.[2020]

Irradiating the hind limb of mice with red light (670 nm) for 5-10 minutes significantly increased blood flow by promoting the release of a nitric oxide precursor, demonstrating its potential for enhancing vasodilation in ischemic tissues.

In a model simulating human peripheral artery disease, repeated light treatment over 14 days led to a sustained increase in blood flow in the affected limb, suggesting that this therapy could be a simple and effective home-based treatment for individuals with impaired blood circulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

In Vivo Characterization of a Red Light-Activated Vasodilation: A Photobiomodulation Study. Keszler, A., Lindemer, B., Broeckel, G., et al.[2023]

Far-infrared (FIR) therapy can enhance skin microcirculation in rats through a mechanism that does not rely on thermal effects, as evidenced by significant increases in blood flow after FIR treatment was stopped.

The study suggests that FIR therapy works by promoting the production of nitric oxide (NO), which is crucial for blood flow regulation, indicating its potential clinical use for treating ischemic conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biological effect of far-infrared therapy on increasing skin microcirculation in rats. Yu, SY., Chiu, JH., Yang, SD., et al.[2022]

An 84-year-old woman with type 2 diabetes successfully healed a 1 cm ulcer on her leg using self-administered photobiomodulation therapy (PBM) with the B-Cure Laser Pro, showing complete healing after 30 days.

This case suggests that PBM therapy could be a safe and effective treatment option for managing leg ulcers in diabetic patients, potentially reducing the need for more invasive procedures like amputation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Auto-Administered Photobiomodulation on Diabetic Leg Ulcers Treatment: A New Way to Manage It? Merigo, E., Tan, L., Zhao, Z., et al.[2022]

Low-level laser therapy (LLLT) has been shown to effectively reduce pain, inflammation, and promote healing, but its acceptance in mainstream medicine is hindered by incomplete understanding of its biochemical mechanisms and varying results from studies.

A biphasic dose response is observed in LLLT, where lower levels of light are more effective for tissue stimulation and repair compared to higher levels, which aligns with the Arndt-Schulz curve concept.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biphasic dose response in low level light therapy. Huang, YY., Chen, AC., Carroll, JD., et al.[2023]

Low-level laser therapy (LLLT) utilizes the unique properties of low-energy laser radiation to promote healing and reduce pain, making it a versatile treatment option in various medical fields such as regenerative medicine, dentistry, and physiotherapy.

LLLT is effective in applications like wound healing, scar improvement, and pain reduction, demonstrating its potential as a safe and non-invasive therapeutic method in both clinical practice and research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Use of Low-Level Energy Laser Radiation in Basic and Clinical Research. Rola, P., Doroszko, A., Derkacz, A.[2019]

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]

Both low-level laser therapy and LED light sources can effectively induce vasodilation in porcine coronary arteries, with maximum relaxation observed at an energy density of 10 J/cm², achieving comparable results between the two light sources.

The vasodilation effect is mediated by a nitric oxide-dependent mechanism, suggesting that these light therapies could be beneficial in clinical settings, such as during coronary artery bypass surgery, to facilitate easier suturing of blood vessels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Light-induced vasodilation of coronary arteries and its possible clinical implication. Plass, CA., Loew, HG., Podesser, BK., et al.[2015]

Citations

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

Far Red Light Therapy for Peripheral Arterial Disease Low-level laser therapy (LLLT) significantly increased nitric oxide (NO) levels in the venous blood of 15 healthy subjects, indicating its potential efficacy in ...

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

In Vivo Characterization of a Red Light-Activated Vasodilation Low-level red-light therapy increases NO bioavailability locally and most efficiently when enzymatic NO production is compromised during ...

3. 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 ...

4. 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.

5. 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 ...