Study of the Effectiveness of Three Different Doses of OPC-34712 in the Treatment of Adults With Acute Schizophrenia (VECTOR)
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ClinicalTrials.gov Identifier: NCT01396421 |
Recruitment Status :
Completed
First Posted : July 18, 2011
Results First Posted : October 29, 2015
Last Update Posted : October 29, 2015
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Condition or disease | Intervention/treatment | Phase |
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Acute Schizophrenia | Drug: OPC-34712 [Brexpiprazole] High Dose Drug: Experimental: OPC-34712 [Brexpiprazole] Middle Dose Drug: Experimental: OPC-34712 [Brexpiprazole] Low Dose Drug: Placebo | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 636 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | A Phase 3, Multicenter, Randomized, Double-blind, Placebo-controlled Trial of Three Fixed Doses of OPC-34712 in the Treatment of Adults With Acute Schizophrenia |
Study Start Date : | July 2011 |
Actual Primary Completion Date : | January 2014 |
Actual Study Completion Date : | January 2014 |

Arm | Intervention/treatment |
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Experimental: OPC-34712 [Brexpiprazole] High Dose
Higher Dose, tablet, once daily, for six weeks
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Drug: OPC-34712 [Brexpiprazole] High Dose
Higher dose, tablet, once daily, for six weeks |
Experimental: OPC-34712 [Brexpiprazole] Middle Dose
Middle Dose, tablet, once daily, for six weeks
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Drug: Experimental: OPC-34712 [Brexpiprazole] Middle Dose
Middle dose, tablet, once daily, for six weeks |
Experimental: OPC-34712 [Brexpiprazole] Low Dose
Lower Dose, tablet, once daily, for six weeks
|
Drug: Experimental: OPC-34712 [Brexpiprazole] Low Dose
Lower dose, tablet, once daily, for six weeks |
Placebo Comparator: Placebo
Placebo, once daily, for six weeks
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Drug: Placebo
Placebo, once daily, for six weeks |
- Mean Change From Baseline to Week 6 Positive and Negative Syndrome Scale (PANSS) Total Score. [ Time Frame: Baseline to Week 6 ]The PANSS consists of 3 subscales (positive subscale, negative subscale and general psychology subscale) containing a total of 30 symptom constructs and was administered using the Structured Clinical Interview (SCI)-PANSS. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 indicating the absence of symptoms and a score of 7 indicating extremely severe symptoms. The PANSS total score ranged from 30 (best possible outcome) to 210 (worst possible outcome).
- Mean Change From Baseline to Week 6 in Clinical Global Impression - Severity of Illness Scale (CGI-S) Score. [ Time Frame: Baseline to Week 6 ]The severity of illness was rated using the CGI-S which is the key secondary endpoint. To perform this assessment, the rater or study physician answered the following question: "Considering your total clinical experience with this particular population, how mentally ill is the participant at this time?" Response choices included: 0=not assessed; 1=normal, not at all ill; 2=borderline mentally ill; 3=mildly ill; 4=moderately ill; 5=markedly ill; 6=severely ill; and 7=among the most extremely ill participant.
- Mean Change From Baseline to Week 1, 2, 3, 4 and 5 Positive and Negative Syndrome Scale (PANSS) Total Score. [ Time Frame: Baseline to Week 1, 2, 3, 4, 5 ]The PANSS consists of 3 subscales (positive subscale, negative subscale and general psychology subscale) containing a total of 30 symptom constructs and was administered using the Structured Clinical Interview (SCI)-PANSS. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 indicating the absence of symptoms and a score of 7 indicating extremely severe symptoms. The PANSS total score ranged from 30 (best possible outcome) to 210 (worst possible outcome).
- Mean Change From Baseline to Week 1, 2, 3, 4 and 5 in Clinical Global Impression - Severity of Illness Scale (CGI-S) Score. [ Time Frame: Baseline to Week 1, 2, 3, 4 and 5 ]The severity of illness was rated using the CGI-S. To perform this assessment, the rater or study physician answered the following question: "Considering your total clinical experience with this particular population, how mentally ill is the participant at this time?" Response choices included: 0=not assessed; 1=normal, not at all ill; 2=borderline mentally ill; 3=mildly ill; 4=moderately ill; 5=markedly ill; 6=severely ill; and 7=among the most extremely ill participant.
- Mean Change From Baseline to Week 6 in Personal and Social Performance Scale (PSP) [ Time Frame: Baseline to Week 6 ]The PSP is a clinician-rated scale that measures personal and social functioning in 4 domains: socially useful activities (eg, work and study), personal and social relationships, self-care, and disturbing and aggressive behaviors. Impairment in each of these domains was rated as absent, mild, manifest, marked, severe, or very severe. These ratings were then converted to a total score based on a 100-point scale using algorithms to identify the appropriate 10-point interval, and the rater's judgment to determine the total score within the 10-point interval. Participants with a PSP total score of 71 to 100 were considered to have mild functional difficulty. Scores of 31 to 70 represented manifest disabilities of various degrees and ratings of 1 to 30 indicated minimal functioning that required intense support and/or supervision.
- Mean Change From Baseline to Week 6 in PANSS Positive Subscale Score [ Time Frame: Baseline to Week 6 ]For each symptom construct of the PANSS Positive Subscale, severity was rated on a 7-point scale, with a score of 1 indicating the absence of symptoms and a score of 7 indicating extremely severe symptoms. The symptom constructs were as follows: delusions, conceptual disorganization, hallucinatory behavior, excitement, grandiosity, suspiciousness/persecution, and hostility. The PANSS Positive Subscale Score for each participant was calculated as the sum of the rating assigned to each of the 7 subscale items, and ranged from 7 to 49 with a higher score indicating greater severity of symptoms.
- Mean Change From Baseline to Week 6 in PANSS Negative Subscale Score [ Time Frame: Baseline to Week 6 ]For each symptom construct of the PANSS Negative Subscale, severity was rated on a 7-point scale, with a score of 1 indicating the absence of symptoms and a score of 7 indicating extremely severe symptoms. The symptom constructs were as follows: blunted affect, emotional withdrawal, poor rapport, passive/apathetic social withdrawal, difficulty in abstract thinking, lack of spontaneity and flow of conversation, stereotyped thinking. The PANSS Negative Subscale Score for each participant was calculated as the sum of the rating assigned to each of the 7 subscale items, and ranged from 7 to 49 with a higher score indicating greater severity of symptoms.
- Clinical Global Impression- Improvement Scale (CGI-I) Score at Week 6 [ Time Frame: Week 6 ]The participant's overall improvement was rated using the CGI-I. The rater or study physician rated the participant's total improvement whether or not it was due entirely to drug treatment. All responses were compared with the participant's condition at screening/baseline. Response choices were: 0=not assessed, 1=very much improved, 2=much improved, 3=minimally improved, 4=no change, 5=minimally worse, 6=much worse, and 7=very much worse.
- Response Rate at Week 6 [ Time Frame: Week 6 ]Response rate was defined as improvement in mean change of ≥30% from baseline in PANSS Total Score at Week 6 or CGI-I score of 1 (very much improved) or 2 (much improved) at Week 6.
- Mean Change From Baseline to Week 6 in PANSS Excited Component (PEC) Score [ Time Frame: Baseline to Week 6 ]The PEC consists of 5 PANSS items (excitement [P4], hostility [P7], tension [G4], uncooperativeness [G8], and poor impulse control [G14]). Each rated on a scale of 1 (absent) to 7 (extreme). The PEC for participants was calculated as the sum of the rating assigned to each of the 5 items, and ranged from 5 to 35 with a higher score indicating greater severity of symptoms.
- Discontinuation Rate for Lack of Efficacy at Week 6 [ Time Frame: Week 6 ]
- Change From Baseline to Week 6 in PANSS Marder Factor Score - Positive Symptoms Score [ Time Frame: Baseline to Week 6 ]The PANSS Marder Factor score - Positive Symptoms Score consists of 8 PANSS items (delusions [P1], hallucinatory behaviour [P3], grandiosity [P5], suspiciousness [P6], stereotyped thinking [N7], somatic concern [G1], unusual thought content [G9], lack of judgment and insight [G10]. Each was rated on a scale of 1 (absent) to 7 (extreme). The PANSS Marder Factor score - Positive Symptoms Score for participants was calculated as the sum of the rating assigned to each of the 8 items, and ranged from 8 to 42 with a higher score indicating greater severity of symptoms.
- Change From Baseline to Week 6 in PANSS Marder Factor Score - Negative Symptoms Score [ Time Frame: Baseline to Week 6 ]The PANSS Marder Factor score - Negative Symptoms Score consists of 7 PANSS items (blunted effect [N1], emotional withdrawal [N2], poor rapport [N3], passive/apathetic social withdrawal [N4], lack of spontaneity and conversation flow [N6], motor retardation [G7], active social avoidance [G16]). The PANSS Marder Factor score - Negative Symptoms Score for participants was calculated as the sum of the rating assigned to each of the 7 items, and ranged from 7 to 49 with a higher score indicating greater severity of symptoms.
- Change From Baseline to Week 6 in PANSS Marder Disorganised Thought Score [ Time Frame: Baseline to Week 6 ]The PANSS Marder Factor score -Disorganized Thought Score consists of 7 PANSS items (conceptual disorganization [P2], difficulty in abstract thinking [N5], mannerisms and posturing [G5], disorientation [G10], poor attention [G11], disturbance of violation [G13], preoccupation [G15]). The PANSS Marder Factor score - Disorganized Thought Score for participants was calculated as the sum of the rating assigned to each of the 7 items, and ranged from 7 to 49 with a higher score indicating greater severity of symptoms.
- Change From Baseline to Week 6 in PANSS Marder Uncontrolled Hostility/Excitement Score [ Time Frame: Baseline to Week 6 ]The PANSS Marder Factor score - Uncontrolled Hostility/Excitement Score consists of 4 PANSS items (excitement [P4], hostility [P7], uncooperativeness [G8], poor impulse control [G14]). The PANSS Marder Factor score - Uncontrolled Hostility/Excitement Score for participants was calculated as the sum of the rating assigned to each of the 4 items, and ranged from 4 to 28 with a higher score indicating greater severity of symptoms.
- Change From Baseline to Week 6 in PANSS Marder Anxiety Depression Score [ Time Frame: Baseline to Week 6 ]The PANSS Marder Factor score - Anxiety/Depression Score consists of 4 PANSS items (anxiety [G2], guilt feelings [G3], tension [G4], depression [G6]). The PANSS Marder Factor score - Anxiety/Depression Score for participants was calculated as the sum of the rating assigned to each of the 4 items, and ranged from 4 to 28 with a higher score indicating greater severity of symptoms.

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Ages Eligible for Study: | 18 Years to 65 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Male or female subjects between 18 and 65 years of age, with a diagnosis of schizophrenia, as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) criteria
- Subjects who have been recently hospitalized or who would benefit from hospitalization for an acute relapse of schizophrenia
- Subjects experiencing an acute exacerbation of psychotic symptoms
- Other protocol specific inclusion criteria may apply
Exclusion Criteria:
- Females who are breast-feeding and/or who have a positive pregnancy test result prior to receiving study drug
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Subjects with a current DSM-IV-TR Axis I diagnosis of:
- Schizoaffective disorder
- Major depressive disorder (MDD)
- Bipolar disorder
- Delirium, dementia, amnestic or other cognitive disorder
- Borderline, paranoid, histrionic, schizotypal, schizoid or antisocial personality disorder
- Subjects presenting with a first episode of schizophrenia
- Other protocol specific exclusion criteria may apply

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01396421

Study Director: | Aleksandar Skuban, M.D. | Otsuka Pharmaceutical Development & Commercialization, Inc. |
Responsible Party: | Otsuka Pharmaceutical Development & Commercialization, Inc. |
ClinicalTrials.gov Identifier: | NCT01396421 |
Other Study ID Numbers: |
331-10-231 |
First Posted: | July 18, 2011 Key Record Dates |
Results First Posted: | October 29, 2015 |
Last Update Posted: | October 29, 2015 |
Last Verified: | September 2015 |
Schizophrenia Schizophrenia Spectrum and Other Psychotic Disorders Mental Disorders Brexpiprazole Serotonin Agents |
Neurotransmitter Agents Molecular Mechanisms of Pharmacological Action Physiological Effects of Drugs Dopamine Agonists Dopamine Agents |