Cariprazine in schizophrenia: clinical efficacy, tolerability, and place in therapy

Cariprazine is a dopamine D3-preferring D3/D2 receptor partial agonist in late-stage clinical development for the treatment of schizophrenia, as well as for bipolar disorder (manic/mixed and depressive episodes), and as an adjunctive agent for the treatment of major depressive disorder. Four phase 2 or 3, 6-week, randomized controlled trials in acute schizophrenia have been completed and reported as poster presentations or in press releases by the manufacturer. Superiority over placebo on the Positive and Negative Syndrome Scale total score was evidenced for cariprazine in daily doses of 1.5, 3.0, 4.5, 6.0, 1.5-4.5, 3.0-6.0, and 6.0-9.0 mg. A randomized controlled trial for the prevention of relapse of schizophrenia is ongoing. In short-term, randomized controlled trials, cariprazine does not appear to adversely impact metabolic variables, prolactin, or the electrocardiogram (ECG) QT interval. In the fixed-dose study of cariprazine that tested 1.5, 3.0, and 4.5 mg/day, the most commonly encountered adverse events were insomnia, extrapyramidal disorder, sedation, akathisia, nausea, dizziness, vomiting, anxiety, and constipation. However, the differences in incidence versus placebo for these events were generally small. If approved by regulatory authorities, cariprazine would join aripiprazole as the second dopamine receptor partial agonist antipsychotic available for clinical use. Cariprazine differs from aripiprazole in terms of dopamine D3 receptor selectivity. Further studies would be helpful to discern the distinguishing features of cariprazine from other second-generation antipsychotics.