The purpose of this study is to assess the PK, Safety, Tolerability (all cohorts) and Efficacy (cohort 3), of once-a-month long-acting SC injection of dose escalating Cariprazine Depot in subjects eligible for treatment with oral Cariprazine.

Key Inclusion Criteria:

• Subjects who meet DSM-5-TR diagnostic criteria for schizophrenia, bipolar I disorder or major depressive disorder (this inclusion criterion relates to cohorts 1 and 2 only).
• Clinically stable subjects (with no evidence of deterioration and on a stable dose of oral antipsychotic or antidepressant medication(s) other than Cariprazine for at least 4 weeks, prior to screening), receiving antipsychotic/s or antidepressant/s other than oral Cariprazine and eligible for treatment with Cariprazine 3 mg/day, with CGI-S score of 1-4.
• Men and women aged 18-64 years (inclusive).
• Body mass index (BMI) 18.5-35.
• Able to sign an informed consent form.
• Adult subjects with a current diagnosis of schizophrenia, who meet DSM-5-TR diagnostic criteria for schizophrenia, naïve to or treated with antipsychotics (this inclusion criterion relates to cohort 3 only).

Key Exclusion Criteria:

• Subjects with schizophrenia with PANSS item scores of > 4 on any of the following: P4 Excitement/Hyperactivity; P6 Suspiciousness/persecution; P7 Hostility; G8 Uncooperativeness; G14 Poor impulse control.
• Subjects with schizoaffective disorder, delirium, dementia, amnestic, or other cognitive disorders or severe personality disorders.
• Use of an investigational drug, and/or participation in clinical studies with an investigational product within 3 months prior to screening.
• History or current cardiovascular or cerebrovascular disease.
• History of seizures or conditions that lower the seizure threshold.
• Use of concomitant administration of strong or moderate CYP3A4 inhibitors.
• Use of concomitant medication of strong or moderate CYP3A4 inducers is contraindicated.
• Subjects with Suicidal Thoughts and Behaviors or has a history of suicidal ideation in the past year, or made a suicide attempt in the past 5 years.
• Subjects with a history of orthostatic hypotension and/or syncope.
• Subjects clinically stable on any dose of oral Cariprazine or add-on treatment (cohorts 1-2 only).
• Subjects with CGI-S score of 5-7.
• Subjects previously treated with partial D2 agonists, aripiprazole and brexipiprazole, and suffered from clinically relevant akathisia.
• For cohort 3 only: Subjects treated with oral Clozapine.