Safety and Tolerability of Oral Paliperidone Extended-Release Tablets in Elderly Patients With Schizophrenia: A Double-Blind, Placebo-Controlled Study With Six-Month Open-Label Extension

Abstract

The objective of this multicenter, international study was to evaluate safety and tolerability of paliperidone extended-release (ER) tablets in elderly (age > or =65 years) patients with schizophrenia. The authors conducted a 6-week, double-blind, randomized, placebo-controlled, optional 24-week open-label extension study. Interventions consisted of flexible, once-daily doses of paliperidone ER (3-12 mg/day; 6-mg starting dose, adjusted in 3-mg dose increments) or placebo (2:1) during double-blind treatment and paliperidone ER only during open-label treatment. Measurements included adverse events, laboratory tests, physical examinations, 12-lead electrocardiograms, movement disorder rating scales, Positive and Negative Syndrome Scale, and Clinical Global Impression scale. The study was not powered to show statistical differences. Patients (N = 114) were predominantly female (73%); mean age was 70 years (double-blind phase). Concomitant disease presence was consistent with that of an older population. During the double-blind phase, discontinuation rates resulting from adverse events were similar between groups (paliperidone ER: 7%, placebo: 8%) as were incidences of treatment-emergent adverse events (paliperidone ER: 67%, placebo: 71%). Serious adverse events occurred in 3% of the paliperidone ER- and 8% of the placebo-treated patients. Elevated prolactin levels occurred in approximately one half of patients. No prolactin- or glucose treatment-related adverse events or noteworthy mean changes in body weight (0 kg [standard deviation: 2.1] and 0 kg [standard deviation: 2.3] for paliperidone ER and placebo, respectively) were observed. Safety and tolerability results in the extension were consistent with the shorter-term results. Efficacy measures did not show consistent statistical improvement between treatment groups. Paliperidone ER (3-12 mg/day) treatment over a 30-week period was generally well-tolerated and may improve symptom severity in elderly patients with schizophrenia.