AEs are any untoward medical occurrence in a clinical investigation participant administered a product or medical device. The event does not need to be causally related to the study treatment or usage. SAEs include any untoward medical occurrence that results in death, are life threatening, requires hospitalization or prolongation of hospitalization, results in disability or incapacity or are a congenital anomaly or birth defect in the offspring of a study participant. Lack of efficacy was to be reported as an AE when it was associated with an SAE.

Psychiatric Adverse Event symptoms included, but were not restricted to, depression, anxiety, hostility, perceptual / thinking disturbance, suicidal ideation, or suicidal behavior based on clinical judgment and use of the Positive and Negative Syndrome Scale and Columbia Classification Algorithm of Suicide assessments.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Total scores range from 30 to 210 with higher scores indicating more extreme symptoms.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Total scores range from 30 to 210 with higher scores indicating more extreme symptoms.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Positive symptoms (productive symptoms) associated with schizophrenia (delusions, conceptual disorganization, and hallucinatory behavior) are rated on a scale from 1 (absent) to 7 (extreme); total positive subscale scores range from 7 to 49 with higher scores indicating more extreme symptoms.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Positive symptoms (productive symptoms) associated with schizophrenia (delusions, conceptual disorganization, and hallucinatory behavior) are rated on a scale from 1 (absent) to 7 (extreme); total positive subscale scores range from 7 to 49 with higher scores indicating more extreme symptoms.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Negative symptoms (deficit features) associated with schizophrenia (blunted affect, emotional withdrawal, poor rapport, and passive / apathetic social withdrawal) are rated on a scale from 1 (absent) to 7 (extreme); total negative subscale scores range from 7 to 49 with higher scores indicating more extreme symptoms.

PANSS includes 30 items rated on a 7-point scale (1=absent, 2=minimal, 3=mild, 4=moderate, 5=moderate severe, 6=severe, 7=extreme) organized as 7 positive symptom subscale items, 7 negative symptom subscale items and 16 general psychopathology items. Negative symptoms (deficit features) associated with schizophrenia (blunted affect, emotional withdrawal, poor rapport, and passive / apathetic social withdrawal) are rated on a scale from 1 (absent) to 7 (extreme); total negative subscale scores range from 7 to 49 with higher scores indicating more extreme symptoms.

10-item rating scale to assess the severity of extrapyramidal symptoms rated on a 5-point scale 0 (normal) to 4 (highest severity). Items measured are gait, arm dropping, shoulder shaking, elbow rigidity, wrist rigidity, leg pendulousness, head dropping, glabella tap, tremor, and salivation. Global score calculated by summing individual item scores and dividing by the total number of items; range is 0 to 40 with higher scores indicating greater severity.

10-item rating scale to assess the severity of extrapyramidal symptoms rated on a 5-point scale 0 (normal) to 4 (highest severity). Items measured are gait, arm dropping, shoulder shaking, elbow rigidity, wrist rigidity, leg pendulousness, head dropping, glabella tap, tremor, and salivation. Global score calculated by summing individual item scores and dividing by the total number of items; range is 0 to 40 with higher scores indicating greater severity.

C-SSRS is a clinician rated assessment of suicidal behavior and / or intent categorized as: Suicidal behavior=a "yes" response to any of 5 suicidal behavior questions (preparatory acts or behavior, aborted attempt, interrupted attempt, actual attempt, and completed suicide); Suicidal ideation=a "yes" response to any one of 5 suicidal ideation questions which includes wish to be dead, and 4 different categories of active suicidal ideation (thought, thought with method, thought with intent, thought with plan and intent).

C-SSRS is a clinician rated assessment of suicidal behavior and / or intent categorized as: Suicidal behavior=a "yes" response to any of 5 suicidal behavior questions (preparatory acts or behavior, aborted attempt, interrupted attempt, actual attempt, and completed suicide); Suicidal ideation=a "yes" response to any one of 5 suicidal ideation questions which includes wish to be dead, and 4 different categories of active suicidal ideation (thought, thought with method, thought with intent, thought with plan and intent).

CGI-S: 7-point clinician rated scale to assess severity of participant's current illness state; range: 1=normal, not ill at all, 2=borderline mentally ill, 3=mildly ill, 4=moderately ill, 5=markedly ill, 6=severely ill, 7=among the most extremely ill patients. Higher scores reflect higher severity of current illness states.

CGI-S: 7-point clinician rated scale to assess severity of participant's current illness state; range: 1=normal, not ill at all, 2=borderline mentally ill, 3=mildly ill, 4=moderately ill, 5=markedly ill, 6=severely ill, 7=among the most extremely ill patients. Higher scores reflect higher severity of current illness states.

CGI-I: 7-point clinician rated scale ranging from 1=very much improved, 2=much improved, 3=minimally improved, 4=no change, 5=minimally worse, 6=much worse, to 7=very much worse. Improvement is defined as a score of 1 (very much improved), 2 (much improved), or 3 (minimally improved) on the scale. Scores above 4 reflect worsening of illness state as compared to baseline.

CGI-I: 7-point clinician rated scale ranging from 1=very much improved, 2=much improved, 3=minimally improved, 4=no change, 5=minimally worse, 6=much worse, to 7=very much worse. Improvement is defined as a score of 1 (very much improved), 2 (much improved), or 3 (minimally improved) on the scale. Scores above 4 reflect worsening of illness state as compared to baseline.

CGI-I: 7-point clinician rated scale ranging from 1=very much improved, 2=much improved, 3=minimally improved, 4=no change, 5=minimally worse, 6=much worse, to 7=very much worse. Improvement is defined as a score of 1 (very much improved), 2 (much improved), or 3 (minimally improved) on the scale. Scores above 4 reflect worsening of illness state as compared to baseline.

Participants considered Responders (4-week CQR \<=10 parts per million \<ppm\>) through reports of cigarette or other nicotine use since last study visit, confirmed by measurement of end-expiratory exhaled carbon monoxide (CO). If any CO measurement at a particular timepoint was \>10 ppm, subject was considered to be Non-Responder at that timepoint.