The primary efficacy variable was time to impending relapse from randomization, as assessed by Clinical Global Impression of Improvement (CGI-I) score ≥5, Positive and Negative Syndrome Scale (PANSS) scores for hostility or uncooperativeness ≥5, or ≥20% increase in PANSS Total Score. Impending relapse was defined as meeting any of the following 5 criteria: 1) CGI-I score of ≥ 5 (minimally worse) and increase in individual PANSS items to a score >4 with an absolute increase of ≥ 2 on that specific item or absolute increase of ≥ 4 on the combined 4 PANSS items (conceptual disorganization, hallucinatory behavior, suspiciousness, unusual thought content).OR 2) CGI-I score of 6 or 7 (much or very much worse) OR 3) Hospitalization due to worsening of illness OR 4) Any suicidal behavior or answers of "yes" to Questions 4 or 5 on the suicidal ideation section of the C-SSRS OR 5) Violent or aggressive behavior resulting in clinically significant injury.The measure type, number is Hazard Ratio.

Based on the Intent-to-Treat (ITT) principle, the full analysis set of this trial was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Impending relapse was defined as meeting any of the following 5 criteria: 1) CGI-I score of ≥ 5 (minimally worse) and increase in individual PANSS items to a score > 4 with an absolute increase of ≥ 2 on that specific item or an increase on any of the following individual PANSS items (conceptual disorganization, hallucinatory behavior, suspiciousness, unusual though content) to a score of >4 and an absolute increase of ≥ 4 on the combined 4 PANSS items. OR 2) CGI-I score of 6 or 7 (much or very much worse) OR 3) Hospitalization due to worsening of illness OR 4) Current suicidal behavior as assessed by the C-SSRS (ie, an answer of "yes" to any of the questions on the suicidal behavior section of the C-SSRS 5) Violent or aggressive behavior resulting in clinically significant self-injury to another person, or property damage.

Based on ITT principle, the full analysis set of this trial was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Participants were assessed for stability using the following criteria:1) Outpatient status AND 2) Positive and Negative Syndrome Scale (PANSS) Total Score ≤ 70 AND 3) A score of ≤ 4 (moderate) on each of the following PANSS items (possible scores of 1 to 7 for each item): conceptual disorganization, suspiciousness hallucinatory behavior, unusual thought content, AND 4) Clinical Global Impression - Severity of Illness scale(CGI-S) score ≤ 4 (moderately ill) AND 5) No current suicidal behavior as assessed by the Columbia-Suicide Severity Rating Scale (C-SSRS), defined as the following: An answer of "no" to each question on the Suicidal Behavior section of the C-SSRS AND an answer of "no" to Questions 4 and 5 on the Suicidal Ideation section of the C-SSRS, if completed, AND 6) No evidence of aggressive or violent behavior resulting in clinically significant self-injury, injury to another person, property damage.

Based on ITT principle, the full analysis set of this trial was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The PANSS consisted of three subscales: a total of 30 symptom constructs. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS total score was the sum of the rating scores for 7 positive scale items, 7 negative scale items, and 16 general psychopathology scale items from the PANSS panel. The PANSS total score ranged from 30 (best possible outcome) to 210 (worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The PANSS consisted of three subscales: a total of 30 symptom constructs. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS total score was the sum of the rating scores for 7 positive scale items, 7 negative scale items, and 16 general psychopathology scale items from the PANSS panel. The PANSS total score ranged from 30 (best possible outcome) to 210 (worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

PANSS consisted of three subscales: a total of 30 symptom constructs. For each construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS positive subscale score was the sum of the rating scores for the 7 positive scale items from the PANSS panel. The 7 positive symptom constructs are delusions, conceptual disorganization, hallucinatory behavior, excitement, grandiosity, suspiciousness/persecution, and hostility. The PANSS positive subscale score ranged from 7 (best possible outcome) to 49 (worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

PANSS consisted of three subscales: a total of 30 symptom constructs. For each construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS positive subscale score was the sum of the rating scores for the 7 positive scale items from the PANSS panel. The 7 positive symptom constructs are delusions, conceptual disorganization, hallucinatory behavior, excitement, grandiosity, suspiciousness/persecution, and hostility. The PANSS positive subscale score ranged from 7 (best possible outcome) to 49 (worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

The PANSS consisted of three subscales: a total of 30 symptom constructs. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS negative subscale score was the sum of the rating scores for the 7 negative scale items from the PANSS panel. The 7 negative symptom constructs: blunted affect, emotional withdrawal, poor rapport, passive apathetic withdrawal, difficulty in abstract thinking, lack of spontaneity and flow of conversation, stereotyped thinking. The PANSS negative subscale score ranged from 7 (best possible outcome) to 49 (worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The PANSS consisted of three subscales: a total of 30 symptom constructs. For each symptom construct, severity was rated on a 7-point scale, with a score of 1 (absence of symptoms) and a score of 7 (extremely severe symptoms). The PANSS negative subscale score was the sum of the rating scores for the 7 negative scale items from the PANSS panel. The 7 negative symptom constructs: blunted affect, emotional withdrawal, poor rapport, passive apathetic withdrawal, difficulty in abstract thinking, lack of spontaneity and flow of conversation, stereotyped thinking. The PANSS negative subscale score ranged from 7 (best possible outcome) to 49 (worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

The severity of illness for each participant was rated using the CGI-S scale. To assess CGI-S, the 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 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 participants.

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The severity of illness for each participant was rated using the CGI-S scale. To assess CGI-S, the 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 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 participants.

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

The rater or investigator would rate the participant's total improvement whether or not it is due entirely to study treatment. During Phase B, responses were compared to the participant's condition at Baseline of Phase B (for participants who entered Phase B directly after screening) or to the End of Phase A visit (for participants who participated in Phase A). During Phase C, responses were compared to the participant's condition at the End of Phase B visit. Response choices include: 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 LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

The PSP is a validated clinician-rated scale that measures personal and social functioning in four domains: socially useful activities (e.g., work and study), personal and social relationships, self-care, and disturbing and aggressive behaviors. Impairment in each of these domains is rated as absent, mild, manifest, marked, severe, or very severe. These ratings are 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 are considered to have mild functional difficulty. Scores of 31 to 70 represent manifest disabilities of various degrees and ratings of 1 to 30 indicate minimal functioning that requires intense support and/or supervision.The PSP score ranges from 0 to 100, with higher scores indicating higher levels of social functioning.

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The PSP is a validated clinician-rated scale that measures personal and social functioning in four domains: socially useful activities (e.g., work and study), personal and social relationships, self-care, and disturbing and aggressive behaviors. Impairment in each of these domains is rated as absent, mild, manifest, marked, severe, or very severe. These ratings are 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 are considered to have mild functional difficulty. Scores of 31 to 70 represent manifest disabilities of various degrees and ratings of 1 to 30 indicate minimal functioning that requires intense support and/or supervision.The PSP score ranges from 0 to 100, with higher scores indicating higher levels of social functioning.

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

The GAF is a clinician-rated scale that assesses the participant's psychological, social, and occupational functioning on a hypothetical continuum of mental health-illness using a scale that ranges from 1 to 100 score, where lower values indicate worst outcome. From among 10 descriptive anchors, investigators will choose the anchor which is the most representative of the participant's level of functioning at the time of the assessment and will assign a single score within the point range given for the selected anchor.

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The GAF is a clinician-rated scale that assesses the participant's psychological, social, and occupational functioning on a hypothetical continuum of mental health-illness using a scale that ranges from 1 to 100 score, where lower values indicate worst outcome. From among 10 descriptive anchors, investigators will choose the anchor which is the most representative of the participant's level of functioning at the time of the assessment and will assign a single score within the point range given for the selected anchor.

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Analysis of the percentage of participants who discontinued due to all causes was based on all participants who have been randomized and taken one dose of IMP in the Double-blind Maintenance phase. The trial was completed by sponsor when efficacy was demonstrated at the first pre-specified interim analysis (45 impending relapse events) performed by an independent (unblinded) statistician.

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

The PEC score consisted of five PANSS items: excitement (P4), hostility (P7), tension (G4), uncooperativeness (G8), and poor impulse control (G14). Each of the items were rated on a scale of 1 (absent) to 7 (extreme). The PEC scores ranged from 5 (not present) to 35 (extremely severe).

The last-observation-carried-forward (LOCF) data set included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data (eg.the last visit prior to the first dosing of Phase C) were not be carried forward to impute missing values for the LOCF data set.

The PEC score consisted of five PANSS items: excitement (P4), hostility (P7), tension (G4), uncooperativeness (G8), and poor impulse control (G14). Each of the items were rated on a scale of 1 (absent) to 7 (extreme). The PEC scores ranged from 5 (not present) to 35 (extremely severe).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The positive factor score is the sum of the 8 components of the positive symptoms scale (range: 8 - best possible outcome to 56 - worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The positive factor score is the sum of the 8 components of the positive symptoms scale (range: 8 - best possible outcome to 56 - worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The negative factor score is the sum of the 7 items of the negative subscale (range: 8 - best possible outcome to 56 - worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The negative factor score is the sum of the 7 items of the negative subscale (range: 8 - best possible outcome to 56 - worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The disorganized thoughts factor score is the sum of score from the 7 items on the disorganized thoughts subscale (range: 7 - best possible outcome to 49 - worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The disorganized thoughts factor score is the sum of score from the 7 items on the disorganized thoughts subscale (range: 7 - best possible outcome to 49 - worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The uncontrolled hostility/excitement factor score is the sum of score from the 4 items on the uncontrolled hostility/excitement subscale (range: 4 - best possible outcome to 28 - worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The uncontrolled hostility/excitement factor score is the sum of score from the 4 items on the uncontrolled hostility/excitement subscale (range: 4 - best possible outcome to 28 - worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The anxiety/depression factor score is the sum of score from the 4 items on the anxiety/depression subscale (range: 4 - best possible outcome to 28 - worst possible outcome).

Based on ITT principle, the full analysis set was composed of all participants randomized to the double-blind treatment who took at least one dose of study medication in Phase C and who had at least one post-randomization efficacy evaluation in Phase C.

Retrospective factor analyses have been performed in recent decades using scores for the 30 individual PANSS items to categorize symptoms into 5 dimensions. Collectively, these dimensions are referred to as the PANSS Marder Factor scores and include positive symptoms score, negative symptoms score, thought score, uncontrolled hostility/excitement, anxiety depression score. The anxiety/depression factor score is the sum of score from the 4 items on the anxiety/depression subscale (range: 4 - best possible outcome to 28 - worst possible outcome).

The LOCF data set for Phase C included data recorded at a given Phase C visit or, if no observation is recorded at that visit, data carried forward from the previous Phase C visit. Baseline data was not be carried forward to impute missing values for the LOCF data set.