Effect of Lofexidine and Oral THC on Marijuana Withdrawal and Relapse

This study has been completed.
Information provided by (Responsible Party):
New York State Psychiatric Institute
ClinicalTrials.gov Identifier:
First received: September 7, 2006
Last updated: February 4, 2013
Last verified: February 2013

The purpose of this study is to investigate the interaction between marijuana and two potential treatment medications: lofexidine and oral THC, with the direct goal of using this information to improve marijuana treatment outcome.

Condition Intervention Phase
Marijuana Dependence
Drug: Lofexidine
Drug: dronabinol
Drug: Marijuana
Phase 2

Study Type: Interventional
Study Design: Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Basic Science
Official Title: Effect of Lofexidine and Oral THC on Marijuana Withdrawal and Relapse

Resource links provided by NLM:

Further study details as provided by New York State Psychiatric Institute:

Primary Outcome Measures:
  • marijuana relapse [ Time Frame: 4 days ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • marijuana withdrawal symptoms [ Time Frame: 3 days ] [ Designated as safety issue: No ]

Other Outcome Measures:
  • cardiovascular effects [ Time Frame: 7 days ] [ Designated as safety issue: No ]

Enrollment: 8
Study Start Date: August 2005
Study Completion Date: September 2008
Primary Completion Date: June 2007 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: lofexidine, dronabinol, marijuana
lofexidine (.6 mg qid), dronabinol (20 mg tid)
Drug: Lofexidine
alpha 2 adrenergic agonist, hypothesized to decrease noradrenergic activity
Other Name: Britlofex
Drug: dronabinol
cannabinoid agonist hypothesized to decrease MJ withdrawal
Other Name: THC
Drug: Marijuana
marijuana intoxication, withdrawal and relapse assessed
Other Name: cannabis

Detailed Description:

Only a small percentage of dependent-marijuana smokers who are seeking treatment for their marijuana use is able to achieve sustained abstinence. The objective of this study is to investigate the interaction between marijuana and two potential treatment medications: lofexidine and oral THC, with the direct goal of using this information to improve marijuana treatment outcome. In mice, the α2-receptor agonist, clonidine, reversed symptoms of cannabinoid withdrawal (Lichtman et al., 2001). The purpose of this study is to determine if lofexidine, an α2-receptor agonist with a more favorable side-effect profile than clonidine, decreases symptoms of marijuana withdrawal and thus decreases marijuana relapse, as compared to placebo. Oral THC is FDA-approved for appetite enhancement. Lofexidine, which is currently not FDA-approved, is used in Europe to treat symptoms of heroin withdrawal, and to treat hypertension. For the purposes of this model, relapse is defined to a return to marijuana use after a period of abstinence. We have shown that oral THC reduces symptoms of marijuana withdrawal at doses that produce minimal intoxication (Haney et al., 2004). Thus, the effects of oral THC alone and in combination with lofexidine will be determined. The study will utilize an inpatient/outpatient, counter-balanced design, with each participant maintained on each of four medication conditions for 8 days each: placebo, lofexidine, oral THC, and oral THC combined with lofexidine. During the inpatient study phases, participants will have the opportunity to self-administer placebo or active marijuana 6 times per day. Outpatient phases are for medication clearance so no medications will be administered. This study will provide important information of the effect of these potential treatment medications on both marijuana withdrawal symptoms, and on subsequent marijuana self-administration.


Ages Eligible for Study:   21 Years to 45 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Current marijuana use: average of 3 marijuana cigarettes at least 4 times per week for the past 4 weeks
  • Able to perform study procedures
  • 21-45 years of age
  • Women practicing an effective form of birth control (condoms, diaphragm, birth control pill, IUD)

Exclusion Criteria:

  • Current, repeated illicit drug use (other than marijuana)
  • Presence of significant medical illness (e.g., diabetes, cardiovascular disease, hypertension, clinically significant laboratory abnormalities)
  • Bradycardia (55 beats/minute), hypotension (< 90 mmHg) including orthostatic hypotension (> 20 mmHg decrease in SP, or > 10 mmHg decrease in DP upon standing
  • History of heart disease
  • Request for drug treatment
  • Current parole or probation
  • Pregnancy or current lactation
  • Recent history of significant violent behavior
  • Major current Axis I psychopathology (e.g., major depressive disorder, bipolar disorder,suicide risk, schizophrenia)
  • Current use of any prescription or over-the-counter medication
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00373503

United States, New York
New York State Psychiatric Institute
New York, New York, United States, 10032
Sponsors and Collaborators
New York State Psychiatric Institute
Principal Investigator: Margaret Haney, Ph.D. New York State Psychiatric Institute
  More Information

No publications provided

Responsible Party: New York State Psychiatric Institute
ClinicalTrials.gov Identifier: NCT00373503     History of Changes
Other Study ID Numbers: 4942, R01DA019239
Study First Received: September 7, 2006
Last Updated: February 4, 2013
Health Authority: United States: Food and Drug Administration

Keywords provided by New York State Psychiatric Institute:
Oral THC

Additional relevant MeSH terms:
Marijuana Abuse
Cannabinoid Receptor Agonists
Cannabinoid Receptor Modulators
Chemically-Induced Disorders
Mental Disorders
Substance-Related Disorders
Adrenergic Agents
Adrenergic Agonists
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Analgesics, Non-Narcotic
Antihypertensive Agents
Cardiovascular Agents
Central Nervous System Agents
Hormones, Hormone Substitutes, and Hormone Antagonists
Molecular Mechanisms of Pharmacological Action
Narcotic Antagonists
Neurotransmitter Agents
Peripheral Nervous System Agents
Pharmacologic Actions
Physiological Effects of Drugs
Psychotropic Drugs
Sensory System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on August 31, 2015