Study Still Provides Valuable Insights
By Alison Singer
A new multi-site clinical trial of Celexa (citalopram), a medication commonly prescribed to children with autism spectrum disorders (ASD), indicated that Celexa was no more effective than a placebo at reducing repetitive behaviors. Celexa has been widely prescribed to patients with obsessive compulsive disorder, the symptoms of which can appear similar to the obsessive behaviors shown by some children with autism. Nearly 150 children participated in the study and were assigned randomly to receive either placebo or citalopram. After 12 weeks, no differences in positive response were found between the two groups on several key measures. But, the children on celexa did experience far more side effects than the children on placebo, including “activation response” (agitation, increased activity, sleep problems).
SSRIs are among the most widely prescribed treatments for children with autism. Previous, but smaller, studies had indicated some effectiveness in reducing repetitive behaviors. Of course it is disappointing when a treatment that seemingly has potential to mitigate challenging symptoms of autism is found to be non effective. But treatment studies like this one are valuable regardless of outcome; it’s just as important for parents to know what doesn’t work as it is for them to know what works.
Most interesting to me was the placebo response in this study. Approximately a third of the children treated with placebo showed a positive response. This is similar to the studies of secretin, where more children on placebo showed a positive response than did the children on secretin. This strong placebo response in autism argues for caution in studies that are not placebo-controlled. In an email to me, Dr. Bryan King of Seattle Children’s Hospital, who led the study, suggested that parental change in expectations in some cases “might have created a self-fulfilling prophesy—where if we anticipate that a child will be able to tolerate more, we present him with more—and that can lead to real improvements. The other thing that happens in the course of a clinical trial is the intensity of scrutiny—it’s also possible when we’re really focusing on behaviors in this setting that we see some (positive) things that we weren’t really paying attention to before.”
Several parents have written that these are the types of studies they hope the Autism Science Foundation will fund; studies that yield actionable, clinically relevant information, regardless of outcome. Indeed I agree that we need many more large, multisite studies like this one to guide and inform treatment practice.
AUDIO: To hear and download audio of Dr. King discussing the study, visit: http://www.seattlechildrens.org/home/about_childrens/press_releases/2009/06/004756.asp