By: Yael Waknine
August 5, 2009 — The US Food and Drug Administration (FDA) has approved a long-acting, once-monthly formulation
of paliperidone palmitate injection (Invega Sustenna, Janssen, a division of Ortho-McNeil-Janssen Pharmaceuticals,
Inc) for the acute and maintenance treatment of schizophrenia in adults.
Although schizophrenic symptoms and the risk for relapse can be managed in most patients with continuous, long-term antipsychotic therapy, some 80% of patients relapse within 5 years of diagnosis. The risk for relapse increases as a result of therapeutic noncompliance, which is a common occurrence in patients receiving oral antipsychotics.
“Inconsistent compliance with medications is arguably one of the single greatest impediments to managing the
symptoms of schizophrenia and delaying the time to relapse,” said Henry A. Nasrallah, MD, in a company news
release. “The approval of once-monthly Invega Sustenna will provide healthcare professionals with a treatment option
that is, at the same time, a definitive monitoring tool for uninterrupted medication compliance, which may help optimize clinical outcomes in schizophrenia.”
Dr. Nasrallah is a clinical investigator who worked on the Invega Sustenna clinical trials and a professor of psychiatry
and neuroscience and director of the Schizophrenia Research Program at the University of Cincinnati College of
The clinical trial program consisted of 4 acute symptom control studies and 1 longer-term maintenance study. The 4
studies (n = 1695) demonstrated that extended-release paliperidone injection was significantly more effective than
placebo for improving Positive and Negative Syndrome Scale (PANSS) total scores in schizophrenic patients.
PANSS is a multi-item inventory that measures positive symptoms, negative symptoms, disorganized thoughts,
uncontrolled hostility/excitement, and anxiety/depression.
Results of the longer-term maintenance study (n = 410) revealed that extended-release paliperidone injection
significantly delayed the time to first relapse (P < .0001), with fewer patients experiencing a relapse relative to placebo
(10% vs 34%). Patients receiving placebo had a 3.6-fold higher rate of relapse compared with extended-release
paliperidone palmitate. This study was stopped early because maintenance of efficacy was demonstrated.
Adverse events most commonly reported in paliperidone-treated patients (incidence ≥ 5% and occurring twice as often vs placebo) were injection site reactions, somnolence/sedation, dizziness, akathisia, and extrapyramidal disorder.
Treatment with extended-release paliperidone palmitate should be initiated with a dose of 234 mg on treatment day 1
and then 156 mg 1 week later, with both injections administered in the deltoid muscle. The recommended monthly
maintenance dose is 117 mg; some patients may benefit from lower or higher maintenance doses within the
recommended range of 39 to 234 mg based on individual tolerability and/or efficacy. Monthly maintenance doses can
be administered in either the deltoid or gluteal muscle.
Yael Waknine is a freelance writer for Medscape.