, Volume 205, Issue 1, pp 171–174

The future of endocannabinoid-oriented clinical research after CB1 antagonists

  • Bernard Le Foll
  • David A. Gorelick
  • Steven R. Goldberg



Great interest has been shown by the medical community and the public in the cannabinoid CB1 receptor antagonists, such as rimonabant, for treatment of obesity, metabolic syndrome, and possibly drug addiction.


This novel class of drug has therapeutic potential for other disorders, as the endocannabinoid system is involved in various health conditions. However, rimonabant, the first clinically available member of this class of drugs, has been linked to increased risk of anxiety, depression, and suicidality. Due to those risks, the European Medicines Agency called for its withdrawal from the market in October, 2008. Shortly after this decision, several pharmaceutical companies (Sanofi-aventis, Merck, Pfizer, Solvay) announced that they would stop further clinical research on this class of drug. Here, we provide an overview of those events and make several suggestions for continuing such clinical research, while safeguarding the safety of patients and clinical trial subjects.


Rimonabant CB1 receptor antagonist Pharmacotherapy Safety Drug dependence Addiction Obesity 


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Copyright information

© US Government 2009

Authors and Affiliations

  • Bernard Le Foll
    • 1
  • David A. Gorelick
    • 2
  • Steven R. Goldberg
    • 3
  1. 1.Translational Addiction Research Laboratory, Centre for Addiction and Mental HealthUniversity of TorontoTorontoCanada
  2. 2.Office of the Scientific Director, Intramural Research Program, National Institute on Drug Abuse, National Institutes of HealthDepartment of Health and Human ServicesBaltimoreUSA
  3. 3.Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of HealthDepartment of Health and Human ServicesBaltimoreUSA

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