Generalization of Extinction Learning

Social Anxiety Disorder Clinical Trial

Official title:

Cholinergic Decontextualization of Exposure Therapy for Anxiety

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01900301
• Other study ID #: MH101359-01
• Status: Completed
• Phase: Phase 1
• Start date: August 2013
• Est. completion date: August 2017

Study information

• Verified date: October 2019
• Source: University of California, Los Angeles
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Fear, whether it occurs in humans suffering from an anxiety disorder or in experimental models with rodents, is reduced by exposing the frightened organism to the fearful stimulus in the absence of any negative consequences (i.e., extinction, or exposure therapy). However, fear often renews when the feared stimulus is encountered in a context different from the exposure context. In rats, the investigators found that interfering with the animal's ability to process contexts during extinction by administering an anticholinergic drug prevented fear renewal. This proposal will determine if the beneficial effect of this drug translates to exposure therapy in socially anxious humans. To this end, 100 individuals with Social Phobia who fear public speaking will undergo repeated sessions of exposure to public speaking, within a virtual reality context. Participants will be randomized to either drug placebo, .4mg/.01 mL Scopolamine, .5mg/.01 mL Scopolamine or .6mg/.01 mL Scopolamine, administered via nasal drops, prior to each session of exposure therapy. One month after completion of exposure therapy, context renewal will be tested by comparing physiological and subjective responses to public speaking in the same virtual context as used during exposure therapy versus a context different than the one used during exposure therapy. The goal is to identify the dose of Scopolamine associated with the greatest reduction in context renewal. In addition, a secondary analysis will attempt to identify those individuals who benefit most from Scopolamine-augmentation of exposure therapy.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 60
• Est. completion date: August 2017
• Est. primary completion date: August 2017
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 55 Years

Eligibility

Inclusion Criteria:

1. between the ages of 18 and 55,

2. fluent in English,

3. within normal body weight (BMI=18.5 to 24.9)

4. meet DSM-IV diagnostic criteria for Social Phobia and report a fear of public speaking.

Exclusion Criteria:

1. participant report of a diagnosed medical or neurological disorder

2. prescription or over the counter medications that can interact with Scopolamine, such as anticholinergic medications (e.g. belladonna alkaloids, antihistamines, meclizine, tricyclic antidepressants, and muscle relaxants), cold medicines, cough suppressants. Other drugs that will be reasons for exclusion include: antimuscarinics, nifedipine, parasympathomimetics, amantadine, amoxapine, antacids, antidiarrheals, anxiolytics, hypnotics, atomexetine, bupropion, cisapride, clozapine, cyclobenzaprine, digoxin, disopyramide, dronabinol (THC), ethanol, maprotilline, memantine, metoclopramide, nabilone, olanzapine, opiate agonists, orphenadrine, phenothiazines, potassium salts, quinidine, sedating H1-blockers, topiramate, tricyclic antidepressants, erthyromycin, ketoconazole, and tegaserod.

3. over the counter drugs or substances that may have a sedative effect (e.g. herbal sedatives: ashwagandha, Duboisia hopwoodii, Prostanthera striatiflora, kava, mandrake, valerian, cannabis, passiflora incarnate; Antihistamines: Diphenhydramine, Dimenhydrinate, Doxylamine, Promethazine; Alcohol; Dextromethorphan)

4. individuals with urinary problems (e.g., BPH)

5. pregnant or nursing females (as the effect of Scop on fetuses is not known)

6. suicidality

7. delusions or hallucinations

8. history of substance dependence in last five years or substance abuse within the past 6 months

Related Conditions & MeSH terms

• Anxiety Disorders
• Phobia, Social
• Social Anxiety Disorder

Intervention

Drug:
• Scopolamine
Participants will be randomized to either, .4mg/.01 mL Scopolamine, .5mg/.01 mL Scopolamine or .6mg/.01 mL Scopolamine, administered via nasal drops, prior to each session of exposure therapy
• intranasal placebo
Participants will be randomized to a drug placebo, administered via nasal drops, prior to each session of exposure therapy

Locations

Country	Name	City	State
United States	University of California, Los Angeles	Los Angeles	California

Sponsors (1)

Lead Sponsor	Collaborator
University of California, Los Angeles

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Eye blink startle reflex		change from final exposure session to follow-up (8 weeks following baseline)
Primary	Skin conductance responses and heart rate		change from final exposure session to follow-up (8 weeks following baseline)
Primary	Subjective Units of Distress		change from final exposure session to follow-up (8 weeks following baseline)
Secondary	Self Statements During Public Speaking Scale		change from baseline to follow-up (8 weeks following baseline)
Secondary	Personal Report of Confidence as a Speaker Scale		change from baseline to follow-up (8 weeks following baseline)
Secondary	Subjective units of distress during in vivo speech		change from baseline to follow-up (8 weeks following baseline)