Paliperidone, the major active metabolite of risperidone, is an atypical antipsychotic agent formulated as an extended-release (ER) tablet suitable for once-daily oral administration. Paliperidone ER is approved for the treatment of adolescents aged 12-17 years with schizophrenia in the US (the focus of this review). It is also approved for the treatment of adults with schizophrenia or schizoaffective disorder.
Paliperidone ER has shown efficacy in the treatment of patients aged 12-17 years with acutely symptomatic schizophrenia in a randomized, double-blind, parallel-group, placebo-controlled, multicenter, 6-week trial. The primary endpoint was the change from baseline in Positive and Negative Syndrome Scale (PANSS) total score to day 43 or the final assessment point post-baseline.
Patients with a PANSS total score of 60-120 received one of three weight-based, fixed once-daily doses of paliperidone ER (patients weighing 29 kg to <51 kg: 1.5mg [low-dose], 3mg [medium], or 6mg [high]; patients weighing >51 kg: 1.5mg [low], 6mg [medium], or 12mg [high]), or placebo.
Compared with placebo, significant improvements in mean PANSS total scores were reported for the medium-dose (3-6mg) paliperidone ER treatment groups. There were no significant differences in mean PANSS total scores between the recipients of low-dose or high-dose paliperidone ER versus placebo. Mean PANSS total scores in the actual dose treatment groups (regardless of weight) decreased from baseline (i.e. improved) and were significantly lower for the 3, 6, and 12mg groups than for the placebo group.
Treatment-emergent adverse events were dose related in adolescents with schizophrenia who received weight-based fixed doses of paliperidone ER.