Background: Most patients with schizophrenia exhibit negative symptoms, even during acute episodes. These difficult-to-treat symptoms are often associated with poor functioning and outcomes.
Methods: A post-hoc analysis of pooled data from three 6-week double-blind studies included patients in an acute episode of schizophrenia who received paliperidone extended-release (ER) (3, 6, 9, or 12 mg) or placebo. Based on criteria developed by the authors, patients were stratified by the presence or absence of predominant negative symptoms at baseline (>or=40% of the maximum negative factor score and <40% of the maximum positive factor score on the Positive and Negative Syndrome Scale [PANSS]).
Results: Although these studies were not designed to examine patients with predominant negative symptoms, the criteria identified 23% of acutely ill patients (270/1193). The mean (SD) baseline PANSS negative symptoms factor score, 27.4 (3.3), was 49% of the maximum; the positive symptoms factor score, 23.7 (2.8), was 33% of the maximum. Completion rates with paliperidone ER (n=195) and placebo (n=75) were 64.6% and 44.0%, respectively. Greater improvements occurred with paliperidone ER vs placebo on PANSS (total, negative and other factors), Clinical Global Impressions-Severity and Personal and Social Performance scores at endpoint (all P values <0.05). Adverse events reported in >or=10% of patients were (paliperidone ER vs placebo): headache (14.4% vs 6.7%), insomnia (13.8% vs 21.3%) and sinus tachycardia (10.3% vs 1.3%). Paliperidone ER treatment was associated with a similar response profile in patients without predominant negative symptoms (paliperidone ER, n=647; placebo, n=276).
Conclusions: Schizophrenia patients with predominant negative symptoms were identified in a population of acutely ill patients. Findings of this post-hoc analysis suggest that acutely ill patients with or without predominant negative symptoms respond similarly to treatment with paliperidone ER. No unexpected tolerability findings were observed.