Efficacy of cariprazine across symptom domains in patients with acute exacerbation of schizophrenia: Pooled analyses from 3 phase II/III studies

Schizophrenia affects various symptom domains, including positive and negative symptoms, mood, and cognition. Cariprazine, a dopamine D₃/D₂ receptor partial agonist and serotonin 5-HT_1A receptor partial agonist, with preferential binding to D₃ receptors, is approved for the treatment of adult patients with schizophrenia (US, Europe) and mania associated with bipolar I disorder (US). For these investigations, data were pooled from 3 positive, 6-week, double-blind, placebo-controlled, phase II/III trials of cariprazine in patients with acute exacerbation of schizophrenia (NCT00694707, NCT01104766, NCT01104779); 2 trials were fixed-dose and 1 trial was flexible-dose. Post hoc analyses evaluated mean change from baseline to week 6 in Positive and Negative Syndrome Scale (PANSS) -derived symptom factors (positive symptoms, negative symptoms, disorganized thought, uncontrolled hostility/excitement, anxiety/depression) and PANSS single items for cariprazine (1.5-9.0 mg/d) versus placebo. P values were not adjusted for multiple comparisons. At week 6, statistically significant differences versus placebo were seen for cariprazine on all 5 PANSS factors (P < 0.01 all). Effects sizes ranged from 0.21 (anxiety/depression) to 0.47 (disorganized thought). Dose-response analysis from the fixed-dose studies found significant differences for all cariprazine doses (1.5, 3.0, 4.5, and 6.0 mg/d) versus placebo in PANSS total score, and in negative symptom and disorganized thought factor scores (P < 0.001). Differences between cariprazine and placebo were also statistically significant on 26 of 30 PANSS single items (P < 0.05). In these post hoc analyses, cariprazine was effective versus placebo in improving all 5 PANSS factor domains, suggesting that it may have broad-spectrum efficacy in patients with acute schizophrenia.