Using a diode laser to measure pain in peripheral neuropathy

Diode Laser as a Biomarker for Neuropathic Pain of Peripheral Origin.

This study is testing a new way to measure pain in people with peripheral neuropathy using a laser and comparing it to a lidocaine patch to see if it helps understand and treat their pain better.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 301 (estimated)
• Ages: 18 Years to 69 Years
• Sex: All
• Sponsor: University of Utah (other)
• Drugs / interventions: chemotherapy
• Locations: 2 sites (Palo Alto, California and 1 other locations)
• Trial ID: NCT06030297 on ClinicalTrials.gov

What this trial studies

This study aims to develop and validate a non-invasive biomarker for neuropathic pain caused by peripheral neuropathy. Participants will undergo a double-blind randomized crossover design, receiving either a lidocaine patch or a placebo, while their pain levels are monitored using a visual analogue scale. The study will utilize a diode laser to stimulate nerve fibers in the skin, measuring the sensory threshold and blood flow response to correlate with patient-reported pain. If successful, the findings could lead to improved methods for assessing and treating neuropathic pain.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18-70 with length-dependent, sensory predominant peripheral neuropathy from non-acute acquired causes.

Not a fit: Patients with no complaints of peripheral neuropathy or other foot pain, or those with a medical history of conditions associated with peripheral neuropathy, may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a reliable method for assessing neuropathic pain, leading to better-targeted treatments for patients.

How similar studies have performed: While the approach of using a diode laser as a biomarker is innovative, similar studies have shown promise in assessing pain responses, suggesting potential for success.

Eligibility criteria

Inclusion Criteria:

Inclusion criteria for Objective 1 (Stanford)

1. 18 -70 years of age
2. no complaints of peripheral neuropathy or other foot pain
3. no medical history of disease or medication use associated with peripheral neuropathy (e.g. diabetes)
4. no known allergy to lidocaine

Inclusion Criteria for Objective 2

1. . 18 years of age and older
2. Length dependent, sensory predominant, peripheral neuropathy from any non-acute acquired cause (e.g. diabetes, pre-diabetes, chemotherapy induced), OR musculoskeletal pain from plantar fasciitis or ankle sprain.

Inclusion Criteria for Objective 3

1. 18 years of age and older
2. Length dependent, sensory predominant, peripheral neuropathy from any non-acute acquired cause (e.g. diabetes, pre-diabetes, chemotherapy induced) .
3. Pain rating on Visual Analog Scale (VAS) \> 30mm

Exclusion Criteria:

Exclusion criteria Objective 1 (Stanford)

1. complaints of peripheral neuropathy or other foot pain
2. medical history of disease or medication use associated with peripheral neuropathy (e.g. diabetes)
3. known allergy to lidocaine or other para-aminobenzioc acid derivative (ie: procaine, tetracaine, benzocaine)

Exclusion Criteria Objective 2 and 3

1. Acute peripheral neuropathy (e.g. Guillain Barre Syndrome, glucose correction neuropathy) because of concerns for stability of neuropathic pain over the period of study participation.
2. Bleeding diathesis, or history of severe bleeding with skin wounds.
3. known allergy to lidocaine or other para-aminobenzioc acid derivative (ie: procaine, tetracaine, benzocaine)

4. Taking exclusionary medications related to lidocaine, or with anti-arrhythmic properties, such as tocainide or mexilitine.

5. Severe liver disease

6. People currently receiving chemotherapy.

7. Unable to complete protocol requirements in the judgement of the investigator.-

Where this trial is running

Palo Alto, California and 1 other locations

• Stanford University — Palo Alto, California, United States (RECRUITING)
• University of Utah — Salt Lake City, Utah, United States (NOT_YET_RECRUITING)

Study contacts

• Study coordinator: Cathy Revere

Conditions: Peripheral Neuropathy, Biomarker, neuropathic pain, response biomarker