PK of Lidocaine/Tetracaine and PD Derived From a New Topical Formulation for Treatment of Neuropathic Pain.

NCT06171243 | Completed DMC

• 1 other identifier: 210821002
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Post-herpetic neuralgia (PHN) is the most frequent complications related to herpes zoster, and can persist for months or even years, and require extensive treatment. For this purpose, pharmacological therapies based on tricyclic antidepressants (amitriptyline), central nervous system depressants (pregabalin) and also opioids, have been stablished. However, all the drugs mentioned can cause serious systemic adverse effects that worsen the patient's quality of life. To avoid these complications, topical therapies based on Capsaicin or Lidocaine 5% patches have been developed. However, these treatments have shown dissimilar results in controlling PHN, so a mixed formulation of lidocaine/tetracaine could show better results. For these reasons, the main objective of our work is to evaluate the plasma levels of lidocaine derived from the application of a topical formulation of lidocaine derived from the application of a topical formulation of lidocaine 23%/tetracaine 7% in patients with neuropathic pain.

Conditions

Neuralgia; Neuropathic Pain; Local Anesthetic Complication; Lidocaine Adverse Reaction

Keywords

neuralgia; Neuropathic pain; Local Anesthetic; Lidocaine

Outcome Measures

Primary Outcomes (1)

• Lidocaine plasmatic levels measured by high performance liquid chromatography

  Lidocaine total dose, after using Lidocaine 23%/Tetracaine 7% formulation.10 grams will be applied every 12 hours for a period of 48 hours. Time "0", where time "0" corresponds to the moment of application of the cream for the first time. Group M1 (Sample N1: 30 min, N2: 2 hours, N3: 4 hours, N4: 12 hours, N5: 26 hours) Group M2 (Sample N1: 45 min, N2: 3 hours, N3: 8 hours, N4: 18 hours, N5: 32 hours) Group M3 (Sample N1: 60 min, N2: 4 hours, N3: 12 hours, N4: 24 hours, N5: 38 hours) Group M4 (Sample N1: 90 min, N2: 5 hours, N3: 16 hours, N4: 30 hours, 44 hours)

  From first application of the cream, which will be applied every 12 hours, to 48 hours after the first application

Secondary Outcomes (3)

• Number of Participants with Blood Pressure adverse reactions

  From first application of the cream, which will be applied every 12 hours, to 48 hours after the first application

• Number of Participants with appearance of Heart rate adverse reactions

  From first application of the cream, which will be applied every 12 hours, to 48 hours after the first application

• Number of Participants with appearance of Adverse Drug Reactions

  From first application of the cream, which will be applied every 12 hours, to 48 hours after the first application

Study Arms (1)

PK/PDLido

Patients over 50 years old, with neuropathic pain who are hospitalized at UC-Christus Clinical Hospital, will be candidates for recruitment to the study.

Drug: Lidocaine topical

Interventions

Lidocaine topical DRUG

Patients who agree to participate, will be given the Lidocaine 23%/Tetracaine 7% formulation. The application of the cream will be carried out by a researcher in charge: 1. A skin area of 200 cm2 will be delimited for the application of the formulation throughout the study period. 2. 10 grams will be applied every 12 hours for a period of 48 hours.

Also known as: Lidocaine/Tetracaine

PK/PDLido

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patient with chronic pain

You may qualify if:

• Trigeminal neuralgia
• Postherpetic neuralgia
• Diabetic neuropathy
• Chronic postoperative pain
• Complex regional pain syndrome
• HIV neuropathy
• Peripheral neuropathy

You may not qualify if:

• Intravenous lidocaine and/or other treatment interfering with the protocol

Sponsors & Collaborators

• Pontificia Universidad Catolica de Chile: lead

Study Sites (1)

Pontificia Universidad Catolica de Chile

Santiago, Santiago Metropolitan, 450881, Chile

Location

MeSH Terms

Conditions

Neuralgia

Interventions

Lidocaine; Tetracaine

Condition Hierarchy (Ancestors)

Peripheral Nervous System Diseases; Neuromuscular Diseases; Nervous System Diseases; Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Acetanilides; Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines; para-Aminobenzoates; Aminobenzoates; Benzoates; Acids, Carbocyclic; Carboxylic Acids; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons

Study Officials

• Pablo Iturra, PhD

  Proffesor

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associated Professor

Study Record Dates

• First Submitted: September 21, 2023
• First Posted: December 14, 2023
• Study Start: March 17, 2023
• Primary Completion: September 23, 2024
• Study Completion: July 28, 2025
• Last Updated: July 31, 2025

Record last verified: 2025-07

Locations

CL (1)