Topical Acetaminophen for Itch Relief: a Proof of Concept Study in Healthy Subjects

Pruritus Clinical Trial

Official title:

Topical Acetaminophen for Itch Relief: a Proof of Concept Study in Healthy Subjects

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03997851
• Other study ID #: 20190133
• Status: Completed
• Phase: Phase 1/Phase 2
• Start date: July 22, 2019
• Est. completion date: March 18, 2020

Study information

• Verified date: June 2020
• Source: University of Miami
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Currently, topical antihistamines and corticosteroids are mainly used for itching relief. However, the over the counter antihistamines are not effective on all itch conditions. Acetaminophen is a popular and widely used OTC drug for pain relief. Although its mode of action is still unknown, recent studies have shown that acetaminophen indirectly activates cannabinoid CB1 receptors. Recent studies have shown that topical cannabinoid agonists are effective for itch relief, the efficacy of topical acetaminophen will be tested for non-histaminergic itch relief.

Description:

This will be a single-blinded, vehicle-controlled randomized study in healthy controls to test the efficacy of the topical gel formulation with three differing concentrations of acetaminophen (APAP) for itch relief. To detect medium effects of the treatments with a given α of 0.5 and an error probability of 0.05, with a power of 0.95, the number of participants needed is 36 (10 within post hoc pairwise comparisons).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 17
• Est. completion date: March 18, 2020
• Est. primary completion date: March 18, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 50 Years

Eligibility

Inclusion Criteria:

1. Healthy subjects must be between 18 and 50 years of age.

2. Must be in general good health with no disease or physical conditions that would impair evaluation of itch and pain perception.

3. No history of chronic itch or pain.

4. Must abstain from the use of any systemic or topical anti-histamine, steroid, or pain relief medications from the week prior to the study till the completion of the study.

5. Must abstain from the use of moisturizers on the arms 24 hours before study visits.

Exclusion Criteria:

1. Individuals under 18 or over 50 years of age.

2. Inability to complete the required measures.

3. The presence of an itchy skin disease.

4. Diagnosis of diseased that would affect itch or pain perception (e.g. neuropathies).

5. Currently enrolled in any investigational study in which the subject is receiving any type of drug, biological, or non-drug therapy.

6. Use of oral, topical analgesics, or other medications known to interfere with itch or pain perception in the week prior to the study and throughout the study (e.g. antihistamines, anesthetics, opioids, neuroleptics, etc.).

7. Use of emollients on the arms a week prior to the study and throughout the study.

8. Known allergies to acetaminophen and cowhage.

9. Pregnant women. (Women of child bearing potential will undergo an hCG pregnancy test).

10. Currently incarcerated.

Related Conditions & MeSH terms

• Pruritus

Intervention

Drug:
• Acetaminophen
Topical acetaminophen gel
• Carbomer 980
Topical vehicle gel

Locations

Country	Name	City	State
United States	University of Miami	Miami	Florida

Sponsors (1)

Lead Sponsor	Collaborator
University of Miami

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Peak Itch Intensity Between the Vehicle and Active Treatments During Non-histaminergic Itch Induction	Peak itch intensity between the vehicle and 3 other active treatments (5%, 2.5%, and 1% acetaminophen gels) after non-histaminergic itch induction (cowhage). Itch intensity was measured on a 10cm scale visual analog scale for 10 minutes. 0 was weighted with "no itch" and 10 was weighted with "most itch imaginable".	10 minutes
Primary	Peak Itch Intensity Between the Vehicle and Active Treatments During Histaminergic Itch Induction	Peak itch intensity between the vehicle and 3 other active treatments (5%, 2.5%, and 1% acetaminophen gels) after histaminergic itch induction. Itch intensity was measured on a 10cm scale visual analog scale for 10 minutes. 0 was weighted with "no itch" and 10 was weighted with "most itch imaginable".	10 minutes
Secondary	Thermal Threshold Detection (Heat Pain)	Standardized quantitative sensory testing is performed to measure heat pain threshold (assesses the threshold at which heat pain sensation is first detected). Measured in Celsius.	3 minutes