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

Summary

The R61 will perform a four-part double-blind randomized crossover study transitioning from a pretreatment baseline phase, to randomized treatment with either lidocaine or an identical placebo patch, washout, and alternate arm. DLss measures will be obtained before and after each phase. Twice daily report of pain using a visual analogue scale will track severity of ongoing spontaneous pain in participants. The hybrid biomarker will distinguish between placebo and active treatment arms, will significantly correlate with extent of neuropathic pain reduction during lidocaine, but will not change during the placebo phase or no-treatment lead-in. If preset Go/No-Go criteria are met, the subsequent R33 validation will then compare lidocaine patch and placebo treatment in a blinded, randomized parallel arm study.

Conditions

• Peripheral Neuropathy

Interventions

PROCEDURE

Diode Laser fiber type Selective Stimulator

-Each patient will have an A and C fiber stimulation. Stimulation will be performed on the dorsum of the foot using stimulation previously published parameters to elicit "burning pain," which is from activation of C-fibers and "pinprick" pain from A-fib

DRUG

ZTlido 1.8 % Topical System

ZTLI(diethylamino)-N-(2,6-dimethylphenyl), has an octanol:water partition ratio of 43 at pH 7.4. Each ZTLIDO contains 36 mg of lidocaine (18 mg per gram adhesive) in a non-aqueous base and also contains the following inactive ingredients: butylated hydroxytoluene, dipropylene glycol, isostearic acid, mineral oil, polyisobutylene, silicone dioxide, styrene/isoprene/styrene block copolymer, and terpene resin. DO (lidocaine topical system) 1.8% is a single-layer, drug-in-adhesive topical delivery system comprised of an adhesive material containing 36 mg lidocaine, which is applied to a pliable nonwoven cloth backing and covered with a polyethylene terephthalate film release liner. The release liner is removed prior to application to the skin. The size of ZTLIDO is 10 cm × 14 cm × 0.08 cm. Lidocaine, an amide local anesthetic, is chemically designated as acetamide, 2-

DIAGNOSTIC_TEST

PeriCam PSI NR

It is a method that visualizes tissue blood perfusion in real time. LASCA provides new means to study the microcirculation in ways that were not possible in the past. PeriCam PSI System combines dynamic response and high spatial resolution in one instrument, providing both real-time graphs and video recordings of the tissue being studied. To further enhance its usability, dedicated application software, PIMSoft, has been developed.

DIAGNOSTIC_TEST

Medoc Quantitative Sensory Testing

Quantitative sensory testing (QST) is a method through which sensory nerve function is quantitatively measured, based on responses of the subject. The peripheral sensory nervous system responds to specific stimuli of specific modality and intensity in a specific manner, which is well-known through many decades of research into human sensation. Thermal QST provides information about the function of small diameter unmyelinated (C fibers) and thinly myelinated (A-delta fibers) nerve fibers for which no nerve conduction test, or other objective tests exist. Small fiber nerve damage can manifest itself in thermal hypoesthesia (raised perception thresholds) or hyperalgesia (lowered pain thresholds).

OTHER

Inactive Topical System

Inactive, non-medicated topical system comprised of an adhesive material containing, which is applied to a pliable nonwoven cloth backing and covered with a polyethylene terephthalate film release liner. The release liner is removed prior to application to the skin. The size of the system is 10 cm × 14 cm × 0.08 cm.

Sponsors & Collaborators

• Stanford University

  collaborator OTHER

• National Institutes of Health (NIH)

  collaborator NIH

• National Institute of Neurological Disorders and Stroke (NINDS)

  collaborator NIH

• University of Utah

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Model

SEQUENTIAL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-09-01

Primary Completion

2026-02-09

Completion

2026-02-09

Countries

• United States

Study Locations