The Efficacy and Safety of Quetiapine XR in Patients With Schizophrenia Switched From Other Antipsychotics

Study Overview
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Brief Summary
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Purpose To evaluate the efficacy and safety of once-daily quetiapine extended release (XR) in patients with schizophrenia switched from other antipsychotics which were suboptimal due to insufficient efficacy or insufficient tolerability. Methods: This was a 12-week, open-label study conducted in the Chinese population in Taiwan. Quetiapine XR was administrated at 300 mg on day 1, 600 mg on day 2 and up to 800 mg after day 2. From day 8 until the end of the study, the dose of quetiapine XR was adjusted within 400-800 mg per day, depending on the clinical response and tolerability of the patients.

Official Title
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The Efficacy and Safety of Once-daily Quetiapine Extended Release in Patients With Schizophrenia Switched From Other Antipsychotics

Conditions
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Schizophrenia

Intervention / Treatment
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* Drug: Administration of quetiapine XR


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The participants who were aged from 20 to 65 years and met the diagnosis of schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (DSM-IV-TR) were eligible for the recruitment to the clinical trial. They also fulfilled the criteria including having a score of 4 (moderate) or greater on any of the 7 items of the Positive and Negative Syndrome Scale (PANSS) Positive Symptom Subscale and needed to switch from previous antipsychotics due to insufficient efficacy or insufficient tolerability. Exclusion Criteria: Any DSM-IV-TR Axis I disorder other than schizophrenia, except comorbid obsessive-compulsive disorder, anxiety disorder, eating disorders or impulse control disorders if they had been stable and had not been primary focus of treatment over the previous 6 months An imminent risk of suicide or a danger to self or others Pregnancy or lactation Intolerance or lack of response to quetiapine IR Use of cytochrome P450 3A4 inhibitors or inducers in the 14 days preceding enrolment Administration of a depot antipsychotic injection within one dosing interval before recruitment Unstable or inadequately treated medical illness as judged by the investigator.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 65 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Quetiapine XR<br>Patients had schizophrenia and fulfilled the criteria including having a score of 4 (moderate) or greater on any of the 7 items of the Positive and Negative Syndrome Scale (PANSS) Positive Symptom Subscale and needed to switch from previous antipsychotics due to insufficient efficacy or insufficient tolerability (N=61). They will receive the intervention of administration of quetiapine XR. | Drug: Administration of quetiapine XR<br>* The treatment was initiated with a 7-day cross-titration period. Previous antipsychotic medication was maintained at the original dose from day 1 to day 3; then reduced to 50% of the original dose from day 4 to day 7 and discontinued on day 8. Meanwhile, the patients started quetiapine XR with daily dose at 300 mg on day 1, 600 mg on day 2 and up to 800 mg after day 2. From day 8 until the end of the study, the dose of quetiapine XR was adjusted within 400-800 mg per day, depending on the clinical response and tolerability of the patients.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Efficacy Assessments | The variable of the primary endpoint was the change from baseline to Week 12 in PANSS total and subscale score. | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety Assessments | The occurrence and severity of adverse events (AEs) will be recorded throughout the study to assess the tolerability of quetiapine XR, including AEs spontaneously reported by the patients or observed by the staff. | 12 weeks |