Effectiveness of Aripiprazole for Improving Side Effects of Clozapine in the Treatment of People With Schizophrenia
Condition: Schizophrenia; Insulin Resistance
MeSH terms: Insulin Resistance; Schizophrenia
Study type: Interventional
Phase: Phase 4

Summary: 
      This study will evaluate the effects of combination treatment with aripiprazole and clozapine
      on insulin resistance, blood fat levels, and weight gain in people diagnosed with
      schizophrenia.
    

Detailed description: 
      Schizophrenia is a severely disabling brain disorder. People with schizophrenia often
      experience hallucinations and delusions, as well as overall difficulty with everyday
      functioning. Although the medications available to treat the disorder are generally
      effective, many cause undesirable side effects. Clozapine, for example, is a strong
      tranquilizer that functions like an antipsychotic medication. It has been shown to be
      effective in reducing the symptoms of schizophrenia, but can bring about serious side
      effects, including heart failure, weight gain, and diabetes. Aripiprazole, an atypical
      antipsychotic medication, has been shown to have fewer side effects than older antipsychotic
      drugs. The addition of aripiprazole to a clozapine treatment regimen may reduce the negative
      side effects of clozapine. This study will evaluate the effects of combination treatment with
      aripiprazole and clozapine on insulin resistance, blood fat levels, and weight gain in people
      with schizophrenia.

      Individuals interested in participating in this 8-week, double-blind study will first attend
      a screening session at the study site. Medical and psychiatric evaluations will be completed,
      blood samples will be taken, and an EKG will be performed. Eligible participants will undergo
      baseline assessments and then be randomly assigned to receive either aripiprazole or placebo
      in addition to their prescribed dose of clozapine. Participants will take one 15-mg capsule
      of their assigned medication once a day for 8 weeks. Study visits will occur biweekly for the
      first 8 weeks, followed by one final follow-up visit at Week 12. At each study visit,
      medication will be distributed, and the following criteria will be assessed: vital signs;
      weight; complete blood count; medication side effects; and extrapyramidal symptoms (EPS),
      which are potential neurological side effects of antipsychotic medications and may include
      involuntary movements, tremors, and rigidity. The Week 8 visit will include an EKG, and
      assessments of the following criteria: vital signs; medication side effects; treatment
      efficacy; blood counts; weight and height; and waist and hip circumference. At baseline and
      Week 8, participants will also undergo a frequently sampled intravenous glucose tolerance
      test (FSIVGTT). This involves intravenous infusion of glucose followed by frequent blood
      sampling to measure insulin and glucose concentrations. During the 4 days prior to each
      FSIVGTT, participants will record their food intake and wear an activity monitor.
    

Intervention name(s): Aripiprazole; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): 15-mg dose once a day for 8 weeks; 1 tablet placebo dose once a day for 8 weeks
Intervention MeSH terms: Aripiprazole
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Glucose Metabolism