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Investigation of Naltrexone for Pathological Gambling

This study has been completed.
National Center for Responsible Gaming
Information provided by (Responsible Party):
Marc Potenza, Yale University Identifier:
First received: January 25, 2010
Last updated: August 11, 2017
Last verified: August 2017
The investigators plan to investigate the safety, tolerability, and efficacy of the opioid antagonist naltrexone in Pathological Gambling. We hypothesize that naltrexone will be superior to placebo in reducing gambling urges and behavior, when combined with adjuvant non-pharmacological treatment as usual.

Condition Intervention Phase
Pathological Gambling Drug: Naltrexone Other: Placebo Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Double-Blind Placebo-Controlled Investigation of Naltrexone for Pathological Gambling

Resource links provided by NLM:

Further study details as provided by Marc Potenza, Yale University:

Primary Outcome Measures:
  • Yale Brown Obsessive Compulsive Scale Modified for Pathological Gambling (YBOCS-PG) [ Time Frame: Weekly/bi-weekly visits ]
    The Yale Brown Obsessive Compulsive Scale adapted for Pathological Gambling (PG-YBOCS) was developed to measure the severity and change in severity of pathological gambling symptoms.The PG-YBOCS is a 10-item clinician-administered questionnaire that measures the severity of PG over a specified time interval. Scores of 0 through 4 are assigned to each question according to the severity of the response (0 = least severe response, 4 = most severe response). The first five questions assess urges and thoughts associated with pathological gambling, whereas the last five questions assess the behavioral component of the disorder. Each set of questions is totaled separately as well as together for a total score. The total score can range from 0 (low) to 40 (most severe) with higher numbers representing a more severe form of pathological gambling.

Secondary Outcome Measures:
  • Gambling Symptom Assessment Scale (G-SAS) [ Time Frame: Weekly/bi-weekly visits ]
    The G-SAS is a 12-item self-rated scale designed to assess gambling symptom severity and change during treatment. Each item on the 12-item scale has a score ranging from 0 - 4. All items ask for an average symptom based on the past 7 days. Total score ranges from 0 - 48: extreme = 41 - 48, severe = 31 - 40, moderate = 21 - 30, mild = 8 - 20.

Enrollment: 9
Actual Study Start Date: February 2009
Study Completion Date: January 2017
Primary Completion Date: February 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Naltrexone Drug: Naltrexone
Targeted dosage of 50mg PO daily
Other Name: Naltrexone hydrochloride
Placebo Comparator: Placebo Other: Placebo
Sugar pills daily PO

  Show Detailed Description


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. Men or women over age 18
  2. Current DSM-IV PG Diagnosis as determined by a score of ≥ 5A criteria and B criterion present on the SCI-PG and a score ≥ 5 on the SOGS
  3. Gambling behavior within 2 weeks prior to enrollment
  4. For women, stable use of a medically accepted form of contraception and negative results on urine pregnancy test at study onset
  5. Currently entering, enrolled, or interested in treatment for PG

Exclusion Criteria:

  1. Gambling that does not meet DSM-IV criteria for PG
  2. Unstable medical illness or clinically significant abnormalities on laboratory tests, EKG, or physical examination at screen
  3. Past or current acute hepatitis or liver failure
  4. History of renal impairment
  5. Current or recent (within one week) treatment with an opioid agonist/opioid analgesic or current opioid withdrawal
  6. Opiate agonist maintenance therapy (e.g. methadone)
  7. Known sensitivity to opioid antagonists
  8. Current pregnancy or lactation, or inadequate contraception in women of childbearing potential
  9. A need for medication with unfavorable interactions with naltrexone
  10. Clinically significant suicidality
  11. Lifetime history of dementia, schizophrenia, or any psychotic disorder determined by SCID
  12. Clinically significant cognitive impairment
  13. Previous treatment with naltrexone or nalmefene
  14. Treatment with investigational medication or depot neuroleptics within 3 months
  15. Lack of proficiency in written and spoken English
  16. Unable to travel to study sites for appointments
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01057862

United States, Connecticut
Connecticut DMHAS Problem Gambling Services and Bettor Choice Programs
Middletown, Connecticut, United States, 06457
Connecticut DMHAS Problem Gambling Services and Bettor Choice Programs
New Haven, Connecticut, United States, 06519
Yale University School of Medicine
New Haven, Connecticut, United States, 06519
Sponsors and Collaborators
Yale University
National Center for Responsible Gaming
Principal Investigator: Marc N Potenza, M.D., Ph.D. Yale University
  More Information


Responsible Party: Marc Potenza, Professor of Psychiatry, Child Study, and Neurobiology, Yale University Identifier: NCT01057862     History of Changes
Other Study ID Numbers: 0901004667
Study First Received: January 25, 2010
Results First Received: January 11, 2017
Last Updated: August 11, 2017

Keywords provided by Marc Potenza, Yale University:
Pathological Gambling
Opioid Antagonist

Additional relevant MeSH terms:
Disruptive, Impulse Control, and Conduct Disorders
Mental Disorders
Narcotic Antagonists
Physiological Effects of Drugs
Sensory System Agents
Peripheral Nervous System Agents processed this record on September 21, 2017