Naltrexone for Antipsychotic-Induced Weight Gain
Condition: Schizophrenia; Schizoaffective Disorder; Schizophreniform Disorder; Bipolar Disorder; Severe Major Depression With Psychotic Features
MeSH terms: Weight Gain; Schizophrenia; Bipolar Disorder; Psychotic Disorders
Study type: Interventional

Summary: 
      This study is designed to look at the effects of naltrexone on weight loss in individuals
      treated with antipsychotic medications. Naltrexone is an FDA approved medication for the
      management of alcohol dependence and drug dependence, but has not been fully evaluated for
      its effect on weight loss in individuals with severe mental illness (i.e. schizophrenia,
      schizoaffective disorder, bipolar disorder etc.) The purpose of this study is to find out how
      effective two different doses of oral naltrexone is on reducing body weight when compared to
      placebo (an inactive substance or "sugar pill").
    

Detailed description: 
      Persons with severe mental illness (SMI) die, on average, 25 years earlier than the general
      population1. Most of this early mortality can be attributed to cardiovascular disease (CVD)
      and diabetes mellitus (DM), which are directly related to obesity. Obesity is a leading cause
      of preventable death in the United States, second only to smoking. The physical health of
      patients has become a major focus of schizophrenia care, as recent decades have seen immense
      gains in symptom control and community integration. There is an urgent need for the
      development of interventions that address the obesity crisis in schizophrenia.

      Patients treated with antipsychotic medications have been shown to have a preference for
      diets high in fat and sugar. Patients with schizophrenia typically seek behaviors that
      increase dopamine mediated reward in the brain such as smoking and substance use, both of
      which occur more often in this group than the general population. The system might require
      intact dopamine and opioid function.

      Naltrexone is an oral agent that competitively antagonizes all known opioid receptors in the
      brain. Human studies with naltrexone were completed in individuals with different illnesses,
      including schizophrenia, and have been shown to be a safe and easy agent to use. It is shown
      to decrease craving in alcoholics and is approved by the FDA for the treatment of alcohol
      dependence. Naltrexone is reported to decrease craving for other substances of abuse, like
      nicotine. Furthermore, it has been shown to prevent secondary weight gain due to cessation of
      cigarette smoking at low (25mg and 50 mg), but not higher doses. Naltrexone has been tested
      in human feeding studies, and has been shown to reduce both the quantity of food eaten and
      the choice of palatable foods.

      Subjects will be randomized to either 25, 50 or 0mg of Naltrexone and will take the study
      medication daily for 52 weeks. Subjects will be seen weekly for the first 4 weeks of the
      study, thereafter they will be seen on a bi-weekly (every other week) basis to be assessed
      (i.e. weight, side effect check, paper questionnaires) throughout the remaining 48 weeks of
      treatment.

      The purpose of this study is to determine the efficacy of two doses of naltrexone (25mg &
      50mg) versus placebo for weight and health risk reduction in 144 obese individuals with
      severe mental illness treated with an antipsychotic medication.
    

Intervention name(s): Naltrexone; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): 25 or 50mg (randomized) oral capsule taken once daily for 52 weeks to establish optimal dose for weight loss over the course of the study.
Other intervention name(s): Revia
Intervention MeSH terms: Naltrexone
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: antipsychotic; severe mental illness; weight loss