Paliperidone palmitate versus oral risperidone and risperidone long-acting injection in patients with recently diagnosed schizophrenia

Abstract

Early in the course of illness, patients with schizophrenia may be particularly susceptible to adverse events (AEs). In this post-hoc, subgroup analysis of a 13-week, double-blind, double-dummy, multicenter study, patients recently diagnosed with schizophrenia (≤ 5 years) were administered once-monthly flexible-dose paliperidone palmitate (PP) (n=161; initiation doses, 150 mg eq day 1 and 100 mg eq day 8) [PP doses can be expressed as milligram equivalents (mg eq) of paliperidone or as milligrams (mg) of PP. 150 mg eq paliperidone=234 mg PP; 100 mg eq paliperidone=156 mg PP. In the USA, dosing tends to be expressed in mg] or oral risperidone [during initiation of risperidone long-acting injection (RLAI) days 1-28] and biweekly flexible-dose RLAI (n=173; initial injection day 8). Assessments were performed at baseline and days 4, 15, 22, 36, 64, and 92. Because of RLAI's release profile, data through day 22 correspond to oral risperidone in the RLAI arm. During this period, the AE profile and onset of efficacy of PP and oral risperidone were similar. The overall AE rates at week 13 for PP and RLAI were 54.7 and 50.3%, respectively, for any AE; 11.2 and 8.1% for extrapyramidal symptom-related AEs; and 2.5 and 2.3% for prolactin-related AEs. No significant differences in the mean weight change, most metabolic parameters, or mean efficacy measures were observed at end point. In patients with recently diagnosed schizophrenia, the tolerability and efficacy of PP and RLAI were generally similar over 13 weeks.