A patient experienced an exacerbation of psychotic symptoms/impending relapse if they met any of the following 4 criteria. 1) Clinical Global Impression of Improvement score ≥ 5 and either an increase on any of the following Positive and Negative Syndrome Scale (PANSS) items (conceptual disorganization, hallucinatory behavior, suspiciousness, unusual thought content) to a score > 4 with an increase of ≥ 2 on that item since randomization or an increase on any of the same PANSS items to a score > 4 and an increase of ≥ 4 on the same combined PANSS items since randomization, 2) Hospitalization due to worsening of psychotic symptoms, 3) Clinical Global Impression of Severity of Suicide (CGI-SS) score of 4 or 5 on Part 1 and/or 6 or 7 on Part 2, or 4) Violent behavior resulting in clinically significant self-injury, injury to another person, or property damage.

Intent-to-treat population: All randomized patients.

This is the key secondary Outcome Measure.

Intent-to-treat population: All randomized patients.

A patient was considered to be a responder if all of the following criteria were met. 1) Outpatient status, 2) PANSS total score ≤ 80, 3) Lack of specific psychotic symptoms on the PANSS as measured by a score of ≤ 4 on each of the following items (possible scores of 1 to 7 for each item): Conceptual disorganization, suspiciousness, hallucinatory behavior, unusual thought content, and 4) Clinical Global Impression of Severity of Illness (CGI-S) ≤ 4 (moderately ill) and 5) CGI-SS ≤ 2 (mildly suicidal) on Part 1 and ≤ 5 (minimally worsened) on Part 2.

Intent-to-treat (ITT) population: All randomized patients. Two of the 269 patients in the ITT population did not attend the Last Visit at which this Outcome Measure was assessed and were not included in the analysis.

A patient was considered to have achieved remission if they had a score of ≤ 3 on each of the following PANSS items, maintained for a period of 6 months: Delusions (P1), unusual thought content (G9), hallucinatory behavior (P3), conceptual disorganization (P2), mannerisms/posturing (G5), blunted affect (N1), social withdrawal (N4), and lack of spontaneity (N6).

Intent-to-treat population: All randomized patients who stayed in Phase 4 for at least 6 months and had values for the specific PANSS items P1, G9, P3, P2,G5, N1, N4, and N6.

The PANSS consists of 3 subscales (Positive Subscale, 7 constructs, scores ranged from 7-49, Negative Subscale, 7 constructs, scores ranged from 7-49, General Psychopathology Subscale, 16 constructs, scores ranged from 16-112) containing a total of 30 symptom constructs. 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 30-210 with a higher score indicating more severe symptoms. A negative change score indicates improvement.

Intent-to-treat population: All randomized patients who had PANSS total scores at both baseline and at least 1 post-baseline time point in Phase 4. Last observation carried forward was implemented to impute the missing data at post-baseline visits. Baseline was not carried forward in imputing the missing data at post-baseline visits.

The severity of illness for each patient was rated using the CGI-S. To assess CGI-S, the rater or investigator answered the following question: "Considering your total clinical experience with this particular population, how mentally ill is the patient at this time?" Response choices included: 0 = not assessed; 1 = normal, not ill at all; 2 = borderline mentally ill; 3 = mildly ill; 4 = moderately ill; 5 = markedly ill; 6 = severely ill; and 7 = among the most extremely ill patients. The CGI-S score ranged from 0-7 with a higher score indicating greater illness. A negative change score indicates improvement.

Intent-to-treat population: All randomized patients who had CGI-S scores at both baseline and at least 1 post-baseline time point in Phase 4. Last observation carried forward was implemented to impute the missing data at post-baseline visits. Baseline was not carried forward in imputing the missing data at post-baseline visits.

The PANSS Positive Subscale consists of 7 symptom constructs (delusions, conceptual disorganization, hallucinatory behavior, excitement, grandiosity, suspiciousness/persecution, and hostility). 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. Scores on each subscale ranged from 7-49 with a higher score indicating more severe symptoms. A negative change score indicates improvement.

Intent-to-treat population: All randomized patients who had PANSS sub-scale scores at both baseline and at least 1 post-baseline time point in Phase 4. Last observation carried forward was implemented to impute the missing data at post-baseline visits. Baseline was not carried forward in imputing the missing data at post-baseline visits.

The PANSS Negative Subscale consists of 7 symptom constructs (blunted affect, emotional withdrawal, poor rapport, passive pathetic withdrawal, difficulty in abstract thinking, lack of spontaneity and flow of conversation, stereotyped thinking). 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. Scores on each subscale ranged from 7-49 with a higher score indicating more severe symptoms. A negative change score indicates improvement.

Intent-to-treat population: All randomized patients who had PANSS sub-scale scores at both baseline and at least 1 post-baseline time point in Phase 4. Last observation carried forward was implemented to impute the missing data at post-baseline visits. Baseline was not carried forward in imputing the missing data at post-baseline visits.

The efficacy of the study medication was rated for each patient using the CGI-I scale. The rater or investigator rated the patient's total improvement whether or not it was due entirely to drug treatment. All responses were compared to the patient's condition at Baseline. Response choices included: 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. The CGI-I score ranged from 0-7 with a higher score indicating less improvement/worsening.

Intent-to-treat population: All randomized patients who had CGI-I scores at both baseline and at least 1 post-baseline time point in Phase 4. Last observation carried forward was implemented to impute the missing data at post-baseline visits. Baseline was not carried forward in imputing the missing data at post-baseline visits.

Time to discontinuation was defined as the date of randomization to the date of study discontinuation.

Intent-to-treat population: All randomized patients.