New data presented at the 2009 American Psychiatric Association annual meeting demonstrates that maintenance therapy with long-acting risperidone significantly delays time to relapse in patients with bipolar I disorder.

Bipolar Disorder is often characterized by debilitating mood swings from extreme highs (mania) to extreme lows (depression). Type I Bipolar Disorder is characterized based on the occurrence of at least one manic episode, with or without the occurrence of a major depressive episode.

A randomized, double-blind, placebo-controlled, long-term study was conducted to evaluate the effect of long-acting risperidone as maintenance therapy in patients who met DSM-IV criteria for Bipolar I Disorder who were stable on medications or experiencing an acute manic or mixed episode. In the first phase of the study, 303 patients were stabilized on open-label risperidone for 26 weeks. In the double-blind phase, patients were randomized to either maintenance therapy with risperidone (N=154) or placebo (N=149). The median duration of treatment was nine months for patients in the risperidone group and five months for patients in the placebo group. The primary endpoint was time to relapse of any mood episode (depression, mania, or mixed).

Time to relapse was significantly longer in patients receiving risperidone monotherapy as compared to placebo (p<0.001). In addition, the rate of relapse during the double-blind treatment phase was lower among patients in the risperidone group (30 percent; 42/140) compared with the placebo group (56 percent; 76/135). The median dose of risperidone was 25 mg.

The most common adverse reactions in clinical trials in patients with bipolar disorder were weight increase (5% in monotherapy trial) and tremor and parkinsonism (greater than or equal to 10% in adjunctive therapy).

"This is the first randomized controlled study to demonstrate the efficacy of RLAT as a maintenance therapy in patients with Bipolar Disorder," said Joseph Palumbo, M.D., Franchise Medical Leader, Psychiatry, Central Nervous System and Pain Therapeutic Area, Johnson & Johnson Pharmaceutical Research & Development, L.L.C. (J&JPRD). "These findings are important because the clinical course of Bipolar Disorder is often unpredictable and relapses can be very debilitating."

The study was presented and sponsored by Janssen, a Division of Ortho-McNeil-Janssen Pharmaceuticals, Inc and J&JPRD.