Use of Topical Lidocaine to Reduce Pain in Patients With Diabetic Neuropathy

Study Overview
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Brief Summary
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The purpose of this study is to see if an investigational drug known as the lidocaine 5% patch is safe and effective in reducing the symptoms of diabetic neuropathy, to examine how topical lidocaine affects the nerve endings, and to determine whether treatment with the lidocaine patch can prevent the potential progression to chronic diabetic neuropathy pain in subjects who did not report pain at the start of the study.

Official Title
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Use of Topical Lidocaine (Lidoderm 5% Patch) to Reduce Pain in Patients With Diabetic Neuropathy: Does the Density and Subtype of Sodium Channels Affect Response?

Conditions
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Diabetic Peripheral Neuropathy

Intervention / Treatment
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* Procedure: Skin biopsy
* Drug: Lidocaine 5% patches


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Group 1: 18-70 years of age, non-diabetic with no nervous system disease (healthy control group) Group 2: 18-70 years of age with Type I or Type II diabetes with significantly painful diabetic neuropathy (VAS > 40mm at Baseline) Group 3: 18-70 years of age with Type I or Type II diabetes with non- painful or insignificantly painful diabetic neuropathy (VAS < 40mm at Baseline) Exclusion Criteria: History of clinically significant liver disease, serious peripheral vascular disease, a blood clotting disorder, or any other medical condition felt to be exclusionary by the investigator Allergy to lidocaine Unwillingness to sign informed consent or any other reasons for which the investigator feels the subject cannot complete the study Women who are pregnant, breastfeeding or trying to become pregnant History of slow-healing diabetic foot ulcers Current skin or soft tissue lesions on the foot that will interfere with application of the lidocaine patch and or skin biopsies Subjects taking Class I antiarrhythmics HgA1c > 11% Active cancer within the previous two years except treated basal cell carcinoma of the skin Co-morbidities that can produce neuropathy Subjects taking sodium channel blockers within one week of study treatment and throughout the study Subjects taking any other experimental drugs within 30 days prior to Screening Visit (Visit 1) Application of lidocaine patch to either foot within two weeks of Screening Visit (Visit 1)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Healthy control patients<br>Subjects 18 to 70 years of age, non-diabetic with no nervous system disease. Lidocaine 5% patch applied to both feet daily, Skin biopsies at biaseline and end of study. | Procedure: Skin biopsy<br>* Skin biopsy specimens will processed and analyzed for Nerve fiber count, nerve and skin morphology, and sodium channel specific epitope expression in keratinocytes.<br>Drug: Lidocaine 5% patches<br>* Subject will apply patches to affected area QD for 12 hours then remove.<br>|
| Other: Type I or Type II diabetes with painful diabetic neuropathy<br>18 to 70 years old with significantly painful diabetic neuropathy.Lidocaine 5% patch applied to both feet daily, Skin biopsies at biaseline and end of study. | Procedure: Skin biopsy<br>* Skin biopsy specimens will processed and analyzed for Nerve fiber count, nerve and skin morphology, and sodium channel specific epitope expression in keratinocytes.<br>Drug: Lidocaine 5% patches<br>* Subject will apply patches to affected area QD for 12 hours then remove.<br>|
| Other: patients with non-painful diabetic peripheral neuropathy<br>18-70 years of age with Type I or Type II diabetes with non-painful or insignificantly painful diabetic neuropathy.Lidocaine 5% patch applied to both feet daily, Skin biopsies at baseline, 4 weeks, and end of study. | Procedure: Skin biopsy<br>* Skin biopsy specimens will processed and analyzed for Nerve fiber count, nerve and skin morphology, and sodium channel specific epitope expression in keratinocytes.<br>Drug: Lidocaine 5% patches<br>* Subject will apply patches to affected area QD for 12 hours then remove.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain Scores From Composite Visual Analog Scale | Scores range from 0 to 10 with higher scores indicating higher levels of pain. | baseline, 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Keratinocyte Immunoreactivity of Nav1.6, Nav1.7, CGRP | Pixel intensity (0-256) of immunofluorescence for each individual biomarker. | Baseline, 4 weeks |