Clinical trial NCT03997851: Topical Acetaminophen for Itch Relief: a Proof of Concept Study in Healthy Subjects
Official title: Topical Acetaminophen for Itch Relief: a Proof of Concept Study in Healthy Subjects
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
PHASE2
Conditions: Pruritus
Lead sponsor: University of Miami
Sponsor class: OTHER
First posted: 2019-06-25
Enrollment: 17
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: The antipruritic effect of 3 topical treatments of varying doses and 1 vehicle treatment will be explored in each subject. One study visit will consist of testing all topical formulations on histaminergic induced itch, and second study visit will test all topical formulations on non-histaminergic induced itch.
Primary purpose: TREATMENT

Brief 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.

Detailed 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).

Eligibility criteria: 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.

Primary outcomes:
measure: Peak Itch Intensity Between the Vehicle and Active Treatments During Non-histaminergic Itch Induction
timeFrame: 10 minutes
measure: Peak Itch Intensity Between the Vehicle and Active Treatments During Histaminergic Itch Induction
timeFrame: 10 minutes
Secondary outcomes:
measure: Thermal Threshold Detection (Heat Pain)
timeFrame: 3 minutes
Other outcomes:
Locations:
city: Miami
country: United States
facility: University of Miami
state: Florida
Study officials:
affiliation: University of Miami
name: Gil Yosipovitch, MD
role: PRINCIPAL_INVESTIGATOR
References: