Mid-Atlantic Consortium Newsletter Summer 2013

Treatment of Rett Syndrome with Dextromethorphan

This research project, conducted at the Kennedy Krieger Institute (KKI) in Baltimore and directed by Sakkubai Naidu, M.D., is evaluating the effect of treatment for young girls with Rett syndrome, a relatively rare genetic disorder that affects brain development and causes severe disability. Girls with Rett syndrome have seizures and abnormally exaggerated movements, suggesting that some brain circuits may be overactive due to excess activity of a brain chemical called glutamate, an excitatory neurotransmitter.

There is no cure for Rett syndrome, but dextromethorphan, an ingredient in many common cough medicines, seems to counteract the brain overactivity responsible for some of its symptoms. This study is evaluating the impact of dextromethorphan on affected girls in a carefully controlled clinical trial. In addition to health status, the study will document effects of the drug on behavior and mental abilities.

This type of study is called a “double blind, placebo-controlled clinical trial.” Participants will include two groups of girls with Rett syndrome between two and nine years of age. One group will receive dextromethorphan; a second group will receive an identically-appearing but biologically inactive substance (placebo). Neither participants nor their doctors will know who received dextromethorphan until the study is over, ensuring that any measured benefits of dextromethorpan are truly caused by the drug and not influenced by the hopes and wishes of everyone concerned.

For more information, contact Barbara Ann Bradford in the Neurogenetics Unit by email at bradford@kennedykrieger.org or by telephone at 443-923-2778 or 1-800-873-3377.