Paliperidone Effective and Well Tolerated in Treatment of Acute Schizophrenia: Presented at APA
By Danny Kucharsky

TORONTO, CANADA -- May 24, 2006 -- Paliperidone extended-release (ER) therapy given in a once-daily dose for 6 weeks is effective and well tolerated in the treatment of acute schizophrenia, according to a study presented here at the American Psychiatric Association Annual Meeting (APA).

The 6-week, double-blind, dose-response study of 444 adult patients was described by investigator Stephen Marder, MD, professor of medicine, University of California at Los Angeles, Los Angeles, California. Subjects were randomized to receive paliperidone ER (6 mg or 12 mg), olanzapine (10 mg daily), or placebo. Olanzapine was added as an active comparator.

The paliperidone ER tablet, an investigational psychotropic medication, has been developed using an osmotically controlled-release oral delivery system (OROS), which results in small 24-hour peak-to-trough fluctuations at steady state and provides delivery of the drug without the rapid rise and fall in concentration seen in immediate-release formulations, said Dr. Marder.

Patients enrolled in the study were experiencing an acute episode of schizophrenia, defined as Positive and Negative Syndrome Scale (PANSS) score between 70 and 120.

Forty-three percent of the subjects (n = 192) completed the study. Rates of discontinuation due to lack of efficacy were lower in the paliperidone ER groups compared with placebo.

Demographic and baseline characteristics of the intent-to-treat population (n = 432) were similar in all study groups.

The study found there was a significant improvement in mean PANSS total score at endpoint for both doses of paliperidone versus placebo: 6 mg = -15.7 ? 18.9 (P =.006) and 12 mg = -17.5 ? 19.8 (P <.001). Personal and Social Performance Scale scores improved at endpoint for both paliperidone ER groups compared with placebo (6 mg = 8.8 ? 13.9 [P =.008], 12 mg = 6.6 ? 13.1 [P =.214], placebo = 2.9 ? 13.0).

Improvement in mean PANSS total score for paliperidone ER versus placebo was statistically significant at every postbaseline time point from Day 4 for paliperidone ER 6 mg (P <.05 vs change in placebo group) and from Day 15 for paliperidone ER 12 mg (P <.05 versus change in placebo group), and this was maintained for the remainder of the study in both groups.

Treatment-emergent adverse events were similar in all groups, but highest with paliperidone 12 mg. Mean changes in body weight (kg) at endpoint were 1.0 ? 3.9 with paliperidone 6 mg, 2.0 ? 3.5 with paliperidone 12 mg, 0.4 ? 3.6 with placebo, and 2.7 ? 4.4 with olanzapine.

The weight gain with paliperidone "came out higher than one would have expected," Dr. Marder said. "I think it's a little bit surprising."

Overall, however, he said that paliperidone ER "is clearly an effective antipsychotic."

This study was sponsored by Johnson & Johnson Pharmaceutical Research & Development, LLC, Raritan, New Jersey.

[Presentation title: A 6-week, US-based Placebo-Controlled Study on the Efficacy and Tolerability of Two Fixed Dosages of Oral Paliperidone Extended-release Tablets in the Treatment of Acute Schizophrenia. Abstract NR400]