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Opioid Agonist and Antagonist Effects on Opioid Dependence

This study has been terminated.
(Study terminated due to halt in funding; may resume recruiting in future)
Johns Hopkins University
Information provided by:
National Institute on Drug Abuse (NIDA) Identifier:
First received: September 1, 2005
Last updated: January 11, 2017
Last verified: July 2007
September 1, 2005
January 11, 2017
January 2004
Not Provided
  • Opiate withdrawal [ Time Frame: up to one day ]
  • Opiate agonist symptoms [ Time Frame: up to one day ]
  • Physiologic measures [ Time Frame: up to one day ]
  • Opiate withdrawal
  • Opiate agonist symptoms
  • Physiologic measures
Complete list of historical versions of study NCT00142727 on Archive Site
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Opioid Agonist and Antagonist Effects on Opioid Dependence
The Variability of Agonist and Antagonist Effects as a Function of Level of Physical Dependence
The purpose of this study is to examine the acute agonist and antagonist effects of a full opioid agonist medication, an opioid antagonist medication, and a partial opioid agonist medication in individuals who have different levels of physical opioid dependence.

The pharmacological effects of opioids in opioid dependent individuals can vary as a function of the characteristics of the opioid being studied (e.g., whether it is an agonist, partial agonist, or antagonist; the dose administered; and the route of administration). Another important set of factors influencing the effects produced by opioids is the characteristics of the organism to which the opioid is being administered. One such characteristic is the level of physical dependence in individuals.

Participants in this study will be maintained on different dose levels of an opioid agonist (methadone). The participant will be challenged with a prototypic opioid agonist, antagonist, and a mixed agonist-antagonist with partial agonist features in order to determine the effects that each has on the human body.

Phase 2
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double-Blind
Primary Purpose: Treatment
Opioid-Related Disorders
  • Drug: Methadone
  • Drug: Full opioid agonist
  • Drug: Partial opioid agonist
  • Drug: Opioid antagonist
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*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
February 2006
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Inclusion Criteria:

  • Active opioid dependence
  • Qualifies for opioid agonist treatment (e.g., methadone or buprenorphine)
  • Fulfills DSM-IV diagnostic criteria for opioid dependence

Exclusion Criteria:

  • Significant medical problems, including insulin dependent diabetes mellitus
  • Non-substance use psychiatric disorders (e.g., schizophrenia)
  • Currently seeking treatment for substance abuse
Sexes Eligible for Study: All
18 Years to 55 Years   (Adult)
Contact information is only displayed when the study is recruiting subjects
United States
Not Provided
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National Institute on Drug Abuse (NIDA)
Johns Hopkins University
Principal Investigator: Eric C. Strain, MD Johns Hopkins University
National Institute on Drug Abuse (NIDA)
July 2007

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP