A Comparison of the Effectiveness and Safety of Injectable Risperidone With That of Risperidone Tablets in the Treatment of Patients With Chronic Schizophrenia
Condition: Schizophrenia; Psychotic Disorders
MeSH terms: Schizophrenia; Mental Disorders; Psychotic Disorders
Study type: Interventional
Phase: Phase 3

Summary: 
      The primary purpose of the study is to show that treatment with an injectable formulation of
      risperidone is not less effective than and has a similar safety profile to risperidone
      tablets in patients with chronic schizophrenia.
    

Detailed description: 
      Chronic schizophrenia is a longer-term condition that is characterized by a lack of drive,
      underactivity and slowness, and social withdrawal. As with the acute form of schizophrenia,
      delusions and hallucinations are common. Based on the severity and long-term nature of this
      disease, it is important that patients take their antipsychotic medication regularly.
      Long-acting injectable forms of antipsychotic drugs may eliminate the need for daily oral
      medication and increase a patient's compliance in taking their medication as prescribed by
      their physician. This is a randomized, double-blind, parallel-group study comparing the
      effectiveness and safety of an injectable formulation of risperidone (coated microspheres) to
      risperidone tablets in patients with chronic, stable schizophrenia. The study is composed of
      a screening visit, followed by two study phases: an 8-week run-in period and a 12-week
      double-blind period. In the run-in phase, patients discontinue from other antipsychotic
      drugs, begin receiving oral risperidone, and stay on the optimal oral risperidone dose that
      is determined for each patient for 4 weeks before starting the double-blind period. Patients
      are then randomized to either risperidone tablets or the injectable risperidone formulation
      at the dose level established during the last 4 weeks of run-in. For the next 12 weeks
      patients receive an injection of risperidone every 2 weeks plus daily oral doses of placebo
      or receive a placebo injection every 2 weeks plus daily oral doses of resperidone tablets.
      The primary measure of effectiveness is the change from baseline in the total score for the
      Positive and Negative Syndrome Scale for Schizophrenia (PANSS), a rating scale that measures
      the symptoms of schizophrenia. Additional efficacy testing includes the Clinical Global
      Impressions (CGI), a rating system used to evaluate the severity of clinical change in a
      patient with various diseases affecting the brain. Safety evaluations include the incidence
      of adverse events, results of clinical laboratory tests (hematology, biochemistry,
      urinalysis), measurements of vital signs and body weight, physical examination and
      electrocardiogram (ECG) findings, clinical examination of the injection area (buttocks), and
      the Extrapyramidal Symptoms Rating Scale (ESRS), a scale used to measure effects of
      antipsychotic medications on motor functions of the patient. The study hypothesis is that the
      injectable formulation of risperidone will not be less effective than oral risperidone
      tablets. The injectable formulation of risperidone will be considered less effective than
      oral risperidone if the improvement in total PANSS with injectable risperidone is more than 6
      points worse than the improvement with oral risperidone. Risperidone injections (25, 50 or
      75milligrams [mg]) starting Day 1 of the double-blind phase, then every 2 weeks (total of 12
      weeks) or 2, 4, or 6mg/day risperidone tablets, starting Day 1 of the run-in period and
      continuing for the rest of the study.
    

Intervention name(s): Risperidone Long acting injectable
Intervention type(s): Drug
Intervention MeSH terms: Risperidone
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double
Primary purpose: Treatment
Keywords: chronic schizophrenia, psychotic disorder, risperidone, long-acting injectable, intramuscular injection, antipsychotic agents