Influence of Escitalopram on Fear Conditioning

• ClinicalTrials.gov Identifier: NCT01398514
• Recruitment Status: Completed
• First Posted: July 20, 2011
• Results First Posted: September 27, 2013
• Last Update Posted: June 11, 2014
• Sponsor: Massachusetts General Hospital
• Collaborator: Forest Laboratories
• Information provided by (Responsible Party): Naomi M. Simon, Massachusetts General Hospital

Study Description

Brief Summary:

The purpose of the study is to learn how differences in learning under mildly-stressful circumstances may be changed by taking an antidepressant medication. This medication is called Lexapro (Escitalopram). The investigators will also examine the impact of any anxiety, depression, and stress related symptoms on learning processes. The investigators will also look at the response of these symptoms to Lexapro.

Condition or disease	Intervention/treatment	Phase
Fear Conditioning	Drug: Escitalopram	Phase 4

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 65 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Double (Participant, Investigator)
• Primary Purpose: Basic Science
• Official Title: Pharmacologic Influence of Escitalopram on the Reduction of Fear Acquisition and Triggered Renewal During Fear Conditioning: a Model for the Prevention and Persistence of Learned Fear and Anxiety in Response to Trauma and Stress
• Study Start Date: October 2008
• Actual Primary Completion Date: June 2011
• Actual Study Completion Date: June 2011

Arms and Interventions

Arm	Intervention/treatment
Experimental: Active medication; Escitalopram 10mg/day	Drug: Escitalopram; Escitalopram 10mg/day or matched pill placebo
Placebo Comparator: Placebo; Matched pill placebo	Drug: Escitalopram; Escitalopram 10mg/day or matched pill placebo

Outcome Measures

Primary Outcome Measures :

1. Physiological Reactivity as Measured by Square-root Transformed Skin Conductance Conditioned Response in Early Extinction Trials 1 to 4 [ Time Frame: Day 2 of Fear Conditioning Paradigm (15 to 18 days post medication initiation) ]

   Three-way interaction between group (active vs. placebo), CS (+ vs. -), and trials (1 - 4).

   CS+ refers to the conditioned stimulus associated with the unconditioned stimulus (electric shock). Higher numbers reflect higher skin conductance response to the CS+ (conditioned stimulus).

   CS- refers to the stimulus not associated with the unconditioned stimulus. Higher numbers reflect higher skin conductance response to a CS-.

   Square-root transformed skin conductance conditioned response are reported for trials 1 to 4 of the Early Extinction Phase.

2. Physiological Reactivity as Measured by Square-root Transformed Skin Conductance Conditioned Response in Acquisition Trials 1 to 5 [ Time Frame: Baseline on Day 1 of Fear Conditioning Paradigm (14 to 17 days post medication initiation) ]

   Three-way interaction between group (active vs. placebo), CS (+ vs. -), and trials (1 - 5).

   CS+ refers to the conditioned stimulus associated with the unconditioned stimulus (electric shock). Higher numbers reflect higher skin conductance response to the CS+ (conditioned stimulus).

   CS- refers to the stimulus not associated with the unconditioned stimulus. Higher numbers reflect higher skin conductance response to a CS-.

   Square-root transformed skin conductance conditioned response are reported for trials 1 to 5 of the Acquisition Phase.

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 75 Years (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

1. Male or female outpatients 18 to 75 years of age
2. Must have no current DSM-IV Axis I diagnosis as measured by the SCID (Structured Clinical Interview for DSM-IV-TR axis 1 disorders) with a trained study investigator. Past history of anxiety disorders, major depressive episodes or substance abuse disorders at least six months prior to baseline are not exclusionary.

Exclusion Criteria:

1. Patients will be excluded from entry into the study for current serious medical conditions or other conditions deemed likely to result in surgery or hospitalization.
2. Patients with a history of trauma resulting in head injury related seizures, or with epilepsy (except a prior history of febrile seizures of infancy which are not exclusionary).
3. Pregnant or lactating women or those of childbearing potential not using medically accepted forms of contraception will be excluded.
4. Concurrent use of other antidepressants, benzodiazepines or antipsychotic medications.
5. Patients with a history of hypersensitivity to escitalopram are excluded.
6. Individuals must have discontinued MAO inhibitors more than 14 days before starting study drug.
7. Additional contraindicated drugs during the study are pimozide, furazolidine, isocarboxazid, lazabemide, and St. John's Wort.
8. Participants meeting DSM-IV or SCID criteria for a substance use disorder in the last six months other than nicotine dependence and those with a positive toxicology screen at baseline consistent with evidence of current substance abuse or dependence as determined by clinical interview.
9. A lifetime history of Bipolar or any psychotic disorder is excluded.
10. Current claustrophobia is exclusionary.
11. Patients currently taking any narcotic will be excluded.

Contacts and Locations

Sponsors and Collaborators

Massachusetts General Hospital

Forest Laboratories

Investigators

• Principal Investigator: Naomi M Simon, M.D., M.Sc.; Massachusetts General Hospital

More Information

• Responsible Party: Naomi M. Simon, Principal Investigator, Massachusetts General Hospital
• ClinicalTrials.gov Identifier: NCT01398514
• Other Study ID Numbers: 2008-P-001314
• First Posted: July 20, 2011
• Results First Posted: September 27, 2013
• Last Update Posted: June 11, 2014
• Last Verified: June 2014

Additional relevant MeSH terms:

Citalopram; Serotonin Uptake Inhibitors; Neurotransmitter Uptake Inhibitors; Membrane Transport Modulators; Molecular Mechanisms of Pharmacological Action; Neurotransmitter Agents; Serotonin Agents; Physiological Effects of Drugs; Antidepressive Agents, Second-Generation; Antidepressive Agents; Psychotropic Drugs