Effects Of PF-02545920 On Ketamine-Induced Abnormal Prefrontal Brain Response To Associative Learning In Healthy Subjects

Brief Summary

To evaluate whether PF-02545920 reduces the effects of ketamine on brain activation during causal learning as measured by fMRI compared to placebo in healthy human subjects, and to evaluate whether behavioral measures of abnormal causal learning under ketamine are reduced by treatment with PF 02545920.

Intervention / Treatment

  • Saline (OTHER)
    Saline infusion for 56 minutes
  • PF-02545920 (DRUG)
    PF-02545920 10 mg tablet single dose
  • Ketamine (OTHER)
    Ketamine 0.23 mg/kg bolus over one min; and 0.58 mg/kg/hour maintenance for 56 minutes
  • Placebo (OTHER)
    Placebo tablet single dose

Condition or Disease

  • Healthy

Phase

  • Phase 1
  • Study Design

    Study type: INTERVENTIONAL
    Status: Terminated
    Study results: No Results Available
    Age: 21 Years to 45 Years
    Enrollment: 4 (ACTUAL)
    Funded by: Industry
    Allocation: Randomized
    Primary Purpose: Basic Science

    Masking

    TRIPLE:
    • Participant
    • Investigator
    • Outcomes Assessor

    Clinical Trial Dates

    Start date: Apr 01, 2011
    Primary Completion: Aug 01, 2012 ACTUAL
    Completion Date: Aug 01, 2012 ACTUAL
    Study First Posted: Nov 19, 2010 ESTIMATED
    Results First Posted: Aug 31, 2020
    Last Updated: Mar 19, 2014

    Sponsors / Collaborators

    Lead Sponsor: Pfizer
    Lead sponsor is responsible party
    Responsible Party: N/A

    The study was terminated on November 2, 2012 due to a reassessment of the likelihood of the study meeting its scientific objectives in light of data with the investigational drug obtained from another clinical study. The decision to terminate the trial was not based on any safety concerns.

    Participant Groups

    • Treatments are co-administered

    • Treatments are co-administered

    • Treatments are co-administered

    • Treatments are co-administered

    Eligibility Criteria

    Sex: All
    Minimum Age: 21
    Maximum Age: 45
    Age Groups: Adult
    Healthy Volunteers: Yes

    Inclusion Criteria:

    * Healthy male and/or female subjects between the ages of 21 and 45 years, inclusive. Body Mass Index (BMI) of 17.5 to 30.5 kg/m2; and a total body weight \>50 kg (110 lbs). (Healthy is defined as no clinically relevant abnormalities identified by a detailed medical history, full physical examination, including blood pressure and pulse rate measurement, 12 lead ECG and clinical laboratory tests).
    * Right handed as determined by handedness questionnaire.
    * Able to read and write English as a primary language.

    Exclusion Criteria:

    * Female subjects who are pregnant or breastfeeding.
    * Any evidence of significant psychosis-like symptoms.
    * Known sensitivity to ketamine.

    Primary Outcomes
    • Lateral prefrontal cortex activation as measured by functional MRI (fMRI) BOLD imaging during causal learning and working memory tasks Day 1 of each treatment period
    Secondary Outcomes
    • Lateral prefrontal cortex activation during causal learning and working memory tasks as measured by arterial spin labelling imaging Day 1 of each treatment period
    • Causal learning task prediction error score for stimulus/outcome associations across 3 stages of learning and expectancy violation Day 1 of each treatment period
    • N-back working memory task number correct Day 1 of each treatment period
    • Positive and Negative Syndrome Scale (PANSS) positive and negative subscale total score Day 1 of each treatment period
    • Clinician administered dissociative states scale (CADSS) total score Day 1 of each treatment period

    More Details

    NCT Number: NCT01244880
    Other IDs: A8241014
    Study URL: https://clinicaltrials.gov/study/NCT01244880
    Last updated: Sep 29, 2023