A Study of RO4917838 in Combination With Antipsychotic Treatment in Patients With Schizophrenia.

Study Overview
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Brief Summary
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This study will determine the efficacy and safety of RO4917838 in patients with schizophrenia who are stable on current antipsychotic treatment (olanzapine, que tiapine, risperidone, paliperidone or aripiprazole) with prominent negative or d isorganized thought symptoms. After a 4 week run in period on their current anti psychotic treatment, patients will be randomized to receive placebo 10mg, 30mg, or 60mg of RO4917838 once daily, p.o., as add-on therapy. The anticipated time o n study treatment is <3 months, and the target sample size is 100-500 individual s.

Official Title
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Randomized, Double-blind, Placebo-controlled add-on Trial of the Safety and Efficacy of RO4917838 in Outpatients on Select Atypical Antipsychotics With Prominent Negative or Disorganized Thought Symptoms

Conditions
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Schizophrenia

Intervention / Treatment
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* Drug: RO4917838
* Drug: RO4917838
* Drug: RO4917838
* Drug: Placebo
* Drug: Standard antipsychotic therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients, 18-60 years of age; diagnosis of schizophrenia (based on screening tests); outpatients, with no hospitalization for worsening of schizophrenia within 3 months; medically and psychiatrically stable over prior 1 month and psychiatrically stable without symptom exacerbation within prior 3 months; currently taking no more than 2 antipsychotic drugs. Exclusion Criteria: began a new non-medication treatment for schizophrenia or other psychiatric condition within last 3 months; on >1 antidepressant, or a change in dose of antidepressant within 3 months; alcohol or substance abuse or dependence within 3 months; has previously received RO4917838.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 3<br> | Drug: RO4917838<br>* 60mg po daily<br>Drug: Standard antipsychotic therapy<br>* As prescribed<br>|
| Placebo Comparator: 4<br> | Drug: Placebo<br>* po daily<br>Drug: Standard antipsychotic therapy<br>* As prescribed<br>|
| Experimental: 1<br> | Drug: RO4917838<br>* 10mg po daily<br>Drug: Standard antipsychotic therapy<br>* As prescribed<br>|
| Experimental: 2<br> | Drug: RO4917838<br>* 30mg po daily<br>Drug: Standard antipsychotic therapy<br>* As prescribed<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean change from baseline in PANSS (Positive and Negative Syndrome Scale) negative factor score. |  | Week 8 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in total PANSS score, CGI, PSP, SGLS; cognition status changes. |  | Throughout study | 
| AEs, laboratory parameters, C-SSRS |  | Throughout study |