FDA approves risperidone for two psychiatric conditions

October 2007

The FDA recently approved the antipsychotic drug risperidone to treat schizophrenia and manic episodes of bipolar I disorder in the pediatric population.

“Many of the medications used for the treatment of problem behaviors for these disorders are used off-label, either suggesting that the appropriate studies have not been conducted in the pediatric population or that the efficacy for these purposes are not proven in perhaps any population,” Daniel L. Coury, MD, professor of pediatrics and psychiatry and chief of developmental and behavioral pediatrics of Ohio State University, told Infectious Diseases in Children.

Approval timeline

First approved in 1993 as a treatment for schizophrenia in adults, risperidone (Risperdal, Janssen Pharmaceuticals) was later approved in 2003 as a short-term treatment for symptoms associated with bipolar disorder in adults.

The drug was then approved in 2006 for the treatment of irritability in adolescents aged 5 to 16 years with autism and has also been used off-label for the treatment of anxiety disorders.

“It is now reassuring that there is proven efficacy, but this was shown in the National Institute of Mental Health supported study several years ago prior to FDA approval,” he said. “This approval will probably have more of an effect on primary care pediatricians who tend to be uncomfortable with the use of these medications, especially when they are not FDA approved for these conditions. It also means FDA-approved dosing guidelines improves the care of this population compared to some off-label use of the medication, where dosing tends to be quite variable according to the practitioner and the advice given.”

The current FDA approval for the treatment of schizophrenia in the pediatric population is based upon two short-term (six to eight week), double blind, controlled trials that involved more than 430 adolescents aged 13 to 17 years.

In the first study, patients were randomly assigned to receive either 1 mg to 3 mg once daily (n=55), 4 mg to 6 mg once daily (n=51) or placebo (n=54).

In the second study, patients were randomly assigned to receive either 0.15 mg to 0.6 mg once daily (n=132) or 1.5 mg to 6 mg once daily (n=125).

Results for both studies indicated efficacy of risperidone for all doses; doses greater than 3 mg did not indicate greater efficacy.

The efficacy of risperidone for the treatment of manic episodes associated with bipolar I disorder in 160 participants aged 10 to 17 years was conducted in a three-week, randomized, double blind, placebo controlled, multi-center trial.

Participants were randomly assigned to receive either 0.5 mg to 2.5 mg once daily (n=50), 3 mg to 6 mg once daily (n=61) or placebo (n=58).

Efficacy was demonstrated for all doses; doses greater than 2.5 mg did not indicate greater efficacy.

“Risperidone has been used by the adolescent psychiatric community for some time, but this approval reinforces its use, perhaps even over other unproven medications,” Coury said.

For more information:

• McCracken JT, McGough J, Shah B, et al. Risperidone in children with autism and serious behavioral problems. NEJM. 2002;347:314-321.
• Final labeling of Risperdal at www.fda.gov.