Cariprazine treatment led to greater improvement in the negative symptoms of schizophrenia than was seen with risperidone, found a recent study.
“[T]he difference between treatments seemed to favour cariprazine at every assessment, with statistical significance from week 14,” György Németh, MD, from the Gedeon Richter Plc, Budapest, Hungary, and colleagues reported in the Lancet. “Patients given cariprazine also had a greater improvement in functioning, suggesting that improvement in negative symptoms translated to improved community functioning for these patients,” the authors reported.
“Given the considerable unmet medical need in this therapeutic area, it is important to consider that any amount of change could be clinically relevant to patients without other treatment options.”
The researchers conducted a randomized, double-blind, phase 3b trial involving 66 hospitals, university clinics, and private practices across 11 countries in Europe. The 460 adults, ages 18 to 65 years, who were enrolled in the study all had stable schizophrenia for at least 2 years, and predominant negative symptoms for at least 6 months.
Half the patients received fixed-dose oral cariprazine at 3, 4.5, or 6 mg/day for 26 weeks, whereas the other half took daily risperidone at doses of 3, 4, or 6 mg during the same period. The researchers’ primary outcome was change on the Positive and Negative Syndrome Scale factor score for negative symptoms (PANSS-FSNS).
Although 178 patients in each group completed the full 26 weeks of treatment, the intent-to-treat analysis included 227 of those in the cariprazine group (average 4.2 mg daily dose) and 229 in the risperidone group (average 3.8 mg daily dose). Patients taking cariprazine experienced a greater drop in negative symptoms than those taking risperidone: 8.90 points lower for cariprazine and 7.44 points lower for risperidone (measured in least squares mean change, P =.0022).
“Differences in PANSS total score, positive subscale score, and general psychopathology score were not larger in either group, substantiating that the change in predominant negative symptoms was not a result of improvement in positive or overall symptoms,” the authors reported.
Nine patients needed to be treated with cariprazine for one of them to experience greater improvement on the PANSS-FSNS (number needed to treat, 9).
“When the more stringent threshold for response of 30% or more was applied, the difference between treatments remained significant for cariprazine over risperidone, with [a number needed to treat] of eight,” the authors wrote.
Adverse effects were similar across both groups, with 54% of those in the cariprazine group and 57% of those in the risperidone group reporting insomnia, akathisia, headache, anxiety, or worse schizophrenia symptoms.
Németh G, Laszlovszky I, Czobor P, et al. Cariprazine versus risperidone monotherapy for treatment of predominant negative symptoms in patients with schizophrenia: a randomised, double-blind, controlled trial [published online February 6, 2017]. Lancet. doi: 10.1016/S0140-6736(17)30060-0