Clinical trial NCT01981395: Fenobam on Heat/Capsaicin Induced Hyperalgesia in Healthy Volunteers
Official title: A Double Blind, Randomized, Placebo Controlled, Crossover Study to Investigate the Anti-hyperalgesic Efficacy of a Single Dose of Fenobam on Heat/Capsaicin Induced Cutaneous Hyperalgesia in Adult Healthy Volunteers.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
Conditions: Hyperalgesia
Allodynia
Keywords: fenobam
heat
capsaicin
hyperalgesia
allodynia
mood
cognitive function
Lead sponsor: Washington University School of Medicine
Sponsor class: OTHER
First posted: 2013-11-11
Enrollment: 33
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER

Brief summary: Our goal is to demonstrate that healthy volunteers treated with fenobam will develop a significantly reduced area of cutaneous hyperalgesia compared to volunteers treated with placebo, after exposure to the heat/capsaicin model of cutaneous sensitization. Additionally we are going to assess changes in mood/affect and cognitive function of subjects following administration of fenobam and after cutaneous sensitization compared to baseline.

Detailed description: All subjects will receive a topical dose of capsaicin cream 0.1%(Capzasin-HP) to the forearm at the start of the study visit. The order of the 2 treatment regimens indicated below will be randomized and blinded to subjects and researchers.

Treatment Regimen 1: Fenobam \[1-(3-chlorophenyl)-3-(1-methyl-4-oxo-2-imidazolidinylidine) urea hydrate\]: administration of one 150 mg gelatin capsule.

Treatment Regimen 2: Placebo (lactose monohydrate): administration of one 150 mg gelatin capsule.

Eligibility criteria: Inclusion Criteria:

1. 18-50 year old
2. Good general health with no remarkable medical conditions (e.g. liver, kidney, heart, or lung failure)
3. BMI between 20-33
4. Willing to comply with study guidelines as outlined in protocol \[including: women of childbearing age must be willing to use a double-barrier method (e.g. oral contraception and condom) for contraception during participation in the study\]
5. Willing to provide informed consent

Exclusion Criteria:

1. Anatomical malformation of upper extremities
2. Status post recent trauma or chronic lesions on either forearm
3. Medication use (includes vitamin, herbal, dietary and mineral supplements and grapefruit products during or within 14 days prior to study participation; excludes contraceptives)
4. History of allergy or intolerance to capsaicin
5. History of multiple drug allergies
6. History of addiction to drugs or alcohol (prior or present addiction or treatment for addiction)
7. History of chronic pain syndromes
8. Pregnant and nursing females
9. Smokers

Primary outcomes:
measure: Suppression of the development of cutaneous hyperalgesia and allodynia around the area treated with heat/capsaicin.
timeFrame: During approximately 7 hours of consecutive assessments
Secondary outcomes:
measure: Evaluation of nociception after drug administration as evaluated by prolonged (1 min) thermal stimulation on normal (untreated) skin.
timeFrame: During approximately 7 hours of consecutive assessments
measure: Assessment of Heat Pain Detection Thresholds (HPDT) in normal and sensitized skin pre and post treatment with fenobam.
timeFrame: During approximately 7 hours of consecutive assessments
measure: Absence of significant side effects
timeFrame: 7 days
measure: Assessment of significant change in mood/affect
timeFrame: During approximately 6 hours of consecutive assessments
measure: Assessment of significant change in cognitive function
timeFrame: During approximately 6 hours of consecutive assessments
Other outcomes:
Locations:
city: St. Louis
country: United States
facility: Washington University School of Medicine
state: Missouri
Study officials:
affiliation: Washington University School of Medicine
name: Laura F Cavallone, M.D.
role: PRINCIPAL_INVESTIGATOR
References: