Pilot Study of Pharmaceutical and Behavioral Interventions to Treat Anxiety Disorders

Status

Completed

Phase

Phase 4

Enrollment

186 participants (actual)

Sponsor

Massachusetts General Hospital · Other

Design

Randomized · Open label (no masking)

Countries

1 country

United States

Start

Nov 2010

Primary completion

Jan 2015

Completion

Jan 2015

First posted

29 Jun 2012 (estimated)

Last update posted

23 Feb 2017

Conditions

Posttraumatic Stress Disorder · Anxiety Disorder

The aim of this project is to create fear conditioning paradigm within which the relative strengths of various novel pharmacological and behavioral interventions can be tested. These interventions are intended to reduce the fearfulness associated with fear conditioning by blocking a memory process known as reconsolidation. In fear conditioning, a "conditioned" stimulus (CS) is paired with an aversive "unconditioned" stimulus (US) such as an electric shock, until presentation of the CS alone comes to elicit a fear conditioned response (CR). The investigators hypothesize that by using a more highly prepared CS (i.e. video of spiders); more sensitive subjects (individuals with stronger acquired CRs); and additional experimental probes for the presence of the latent CR, the investigators may develop a normal human paradigm that is not plagued by previously observed floor effects (i.e. intervention is 100% effective), within which both the established techniques of propranolol and delayed extinction will produce significant, but only partial, CR reduction. This would leave room to test and compare potentially more powerful candidate reconsolidation-blocking or memory-updating interventions. To achieve these aims, subjects will undergo a four-day fear conditioning and delayed extinction protocol. Skin conductance response data will be gathered across the different phases of the experiment.

• Active comparator

  Propranolol

  a single dose of 40mg propranolol may be given to begin visit 2, followed by 90min wait and subsequently CS reactivation

• Active comparator

  Reactivation with time delay

  For those not receiving propranolol on visit 2, one experimental CS will be reactivated, followed by a 10 minute break and subsequently extinction

• Experimental

  Mifepristone

  a single dose of 1800mg (200mg tablets) mifepristone may be given to begin visit 2, followed by 90min wait and subsequently CS reactivation

• Experimental

  Intranasal oxytocin

  A single 32IU dose of Syntocinon (intranasal oxytocin) is given to begin visit 2, followed by a 10 minute wait and subsequent CS reactivation.

1. Change From Baseline Skin Conductance Response

   Time frame · 48hrs

   Registry description

   Skin conductance response (SCR) is the change in skin conductance level in response to a stimulus. We compared the SCR to a non-treated conditioned stimulus (CS+N) with the SCR to a treated conditioned stimulus (CS+R) by creating a difference score (CS+R - CS+N) for the day 3 data. Day 3 is 48 hours after the fear-conditioning procedure and serves as the primary measure of whether the treatment had an effect. SCR was measured in microSiemens; the SCR difference score reflects a change in microSiemens.

No study cites this trial.