A Trial of Brexpiprazole in the Treatment of Borderline Personality Disorder

Inclusion Criteria

• Male or female participants, ages 18 to 65, inclusive, at the time of informed consent
• Participants with a primary Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) diagnosis of BPD confirmed by the Structured Clinical Interview for DSM-5 Personality Disorders (SCID-5-PD) at screening.
• At screening and Day 0, participants must have a total score ≥ 12 on the Zanarini Rating Scale for BPD (ZAN-BPD) scale.
• Participants who, in the investigator's judgment, require treatment with a medication for BPD.
• Participants willing to discontinue all prohibited medications to meet protocol-required washouts prior to and during the trial period.

Exclusion Criteria

• Sexually active males or females of childbearing potential who do not agree to practice 2 different methods of birth control or remain abstinent during the trial and for 30 days after the last dose of investigational medicinal product (IMP). Consensual sexual activity that cannot biologically result in pregnancy may not be participant to required birth control methods, following discussion with the medical monitor. Male participants must also agree not to donate sperm from trial screening through 30 days after the last dose of IMP.
• Women who are breastfeeding and/or who have a positive pregnancy test result prior to receiving IMP.
• Participants with a concurrent DSM-5 diagnosis of schizophrenia or schizoaffective disorder. Also, participants with a concurrent diagnosis of bipolar I disorder, bipolar II disorder, delirium, dementia, amnesia, eating disorder, antisocial personality disorder, or other cognitive disorders.
• Participants with a current diagnosis of substance or alcohol use disorder within 90 days prior to screening visit.
• Participants who fulfill the following criteria related to suicide and/or suicidal ideation are excluded:
• Participants who have a significant risk of committing violent acts, serious self-harm, or suicide based on history or routine psychiatric status examination, or those who are homicidal or considered to be a high risk to others, or participants with a response of "yes" on the Columbia-suicide severity rating scale (C-SSRS) Suicidal Ideation Item 5, OR
• Participants with a response of "yes" on the C-SSRS Suicidal Behavior Items, OR
• Participants who have had 3 suicide attempts, OR,
• Participants who have had 3 or more hospitalizations due to suicidal behavior.
• Participants who received brexpiprazole in any prior clinical trial or participants who have taken or are taking commercially available brexpiprazole (Rexulti®).
• Participants who are currently either inpatient or partially hospitalized.
• Participants who participated in a clinical trial within 90 days prior to screening or who participated in more than 2 clinical trials within a year prior to screening.