Cariprazine: an augmentation strategy for treatment-resistant schizophrenia with pro-cognitive and anti-hostility effects.

Schizophrenia is a chronic mental health condition treated with antipsychotics. A significant number of patients fail to respond to standard treatment and develop treatment-resistant schizophrenia (TRS). The only current treatment for TRS is clozapine, which has significant side effects and may only be effective in 40% of cases. We describe two cases of patients with TRS who have failed multiple antipsychotic trials and have had extensive hospitalization history due to aggression/hostility. Both patients responded to dual antipsychotic therapy with a long-acting injectable antipsychotic plus cariprazine. Both patients demonstrated improvement in hostility and cognition/memory. Cariprazine's novel mechanism of action may allow it to be uniquely effective in dual antipsychotic therapy for TRS. Cariprazine has a higher affinity than dopamine for D3 receptors and has a 10-fold higher affinity for D3 than D2. This may contribute to its pro-cognitive and anti-hostility effects. Further studies are warranted to determine the role of cariprazine in TRS.