Early Detection, Intervention and Neurobiology in Autism: Early Intervention Portion

Principal Investigator: Rebecca Landa

The overall goal of the study is to counter the effects of increased N-methyl-D-aspartate (NMDA)/glutamate receptors in mutation-positive Rett syndrome (RTT) subjects by use of dextromethorphan (DM), an agent known to block the NMDA receptor channels. The doses of DM used in this study are known to improve cough and normalize epileptic discharges in electroencephalogram (EEG) of infants and children with non-ketotic hyperglycinemia, by a similar mechanism. We anticipate that the EEG abnormalities in RTT subjects will improve, and that seizure frequency will be reduced. Improvement in respiratory abnormalities, GI dysfunction, motor impairment, bone density, cognition, and temperament are also expected. Additionally, NMDA receptors normally present in osteoblasts may be increased and play a role in osteopenia seen in RTT. Specific primary and secondary outcome measures will be used to determine improvements.