Tuesday, November 14, 2006
Risperidone approved for autism
The Food and Drug Administration has approved risperidone for treatment of irritability associated with autism. This approval addresses aggression, deliberate self-injury, and temper tantrums in children aged 5 years and older, and in adolescents.
In an interview, Dr. Christopher J. McDougle characterized the FDA approval as a major development. “There is no drug currently approved for autism, so it's a tremendous breakthrough,” said Dr. McDougle, the Albert E. Stern Professor and chairman of the department of psychiatry at Indiana University, Indianapolis.
The new indication is based in part on a multicenter, randomized, double-blind study that showed significant behavioral improvements among 49 children treated with risperidone, compared with 52 given a placebo (N. Engl. J. Med. 2002;347:314–21). Researchers assessed response using the Irritability Subscale of the Aberrant Behavior Checklist and the rating on the Clinical Global Impressions-Improvement Scale. There were 33 responders in the risperidone group and 6 responders in the placebo group.
In an open-label, 8-week follow-up study, the 46 nonresponders to placebo were given risperidone, and 30 responded. Researchers then monitored all responders and demonstrated that the benefit of treatment persisted for these patients out to 6 months (Am. J. Psychyiatry 2005;162:1361–9). The authors added, however, that discontinuation after 6 months “was associated with a rapid return of disruptive and aggressive behavior in most subjects.”
These studies were sponsored by the National Institute of Mental Health. The benefit of treatment persisted out to 6 months in the 63 of the children who had a positive response at 8 weeks.
Dr. McDougle emphasized that the approval is not for treatment of autism across the board. “It's important for people to realize the drug is approved for associated symptoms—not the core social and communication symptoms,” he said.
The percentage of pediatric patients with autism who display aggression, deliberate self-injury, and/or temper tantrums is probably in the range of 20%–30%, Dr. Scahill said. He characterized that range as sizable.
I have several adult patients with autism, and have found risperidone effective for treating their hyperactivity and self-injurious behavior.