This week’s “Got Questions” answer comes from Joseph Horrigan, MD, Autism Speaks assistant vice president, head of medical research.
First, it’s important to note that medicines for treating autism are most effective when used in conjunction with behavioral therapies. Ideally, medicines are a complement to other treatment strategies.
Medicines for treating autism’s three core symptoms—communication difficulties, social challenges and repetitive behavior—have long represented a huge area of unmet need. Unfortunately, few drugs on the market today effectively relieve these symptoms and none of the options most often prescribed by practitioners work well for every individual.
In fact, while the Food and Drug Administration (FDA) has approved two drugs for treating irritability associated with the autism (risperidone and aripiprazole), it has yet to approve a medicine for treating autism’s three core characteristics. Nonetheless, medicines such as risperidone and aripiprazole can be beneficial in ways that can ease these core symptoms, because relieving irritability often improves sociability while reducing tantrums, aggressive outbursts and self-injurious behaviors.
The good news is that the range of medication options may soon change, thanks to recent advances in our understanding of the biology that produces autism’s core symptoms. This has made it possible for researchers to begin testing compounds that may help normalize crucial brain functions involved in autism. Early experiments suggest that several compounds with different mechanisms of action have great potential for clinical use, and many are now in clinical trials. [This link takes you to the search engine of the NIH clinical trial network, with results under the search term “autism.”]
Although these developments are exciting and hold real promise for bettering the lives of people with autism, we will have to wait at least a few more years before we know if any of these drug studies produce enough information on safety and effectiveness to merit FDA approval for the treatment of core symptoms.
Today, most medicines prescribed to ease autism’s disabling symptoms are used “off label,” meaning that their FDA approval is for other, sometimes-related conditions such as attention deficit hyperactivity disorder (ADHD), sleep disturbances or depression. Such off-label use is common in virtually all areas of medicine and is usually done to relieve significant suffering in the absence of sufficiently large and targeted studies.
An example in autism would be the class of medicines known as selective serotonin re-uptake inhibitors (SSRIs), including fluoxetine. Several of these medicines are FDA-approved for the treatment of anxiety disorders and depression, in children as well as adults. Although large clinical trials have yet to demonstrate their effectiveness, parents and clinicians have found that they can ease social difficulties among some people with autism. However, it has proven to be difficult to predict which medicines in this class may produce the greatest benefit for a given patient with autism. Similarly, determining the best dose can be quite challenging.
Another example would be naltrexone, which is FDA-approved for the treatment of alcohol and opioid addictions. It can ease disabling repetitive and self-injurious behaviors in some children and adults with autism.
These medicines do not work for everyone, and all medicines have side effects. And as noted above, each person may respond differently to medicines. In addition, changes in response to a medicine can occur as time goes on, even when the dose is not changed. Over time, some people develop tolerance (when a drug stops being effective) or sensitization (when side effects worsen).
Because using these medications in children and adolescents can be a difficult decision for parents, you may find it helpful to use our Medication Decision Tool Kit, a guide for actively working with a physician to find the approach that fits best with your values and goals. You can download it free here.
These are exciting times in the development of new medicines for relieving autism’s most disabling symptoms, and Autism Speaks is increasing its funding and focus in this promising area, while placing great emphasis on ensuring the safety of promising new medicines. Please stay tuned!
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