Clonidine for Neurocognitive Sequelae

The long term prognosis for many children diagnosed with brain tumors and other malignancies has improved dramatically over the last decades and is expected to continue to rise as a result of improved treatment. The increased survival in pediatric oncology, however, has been associated with an increased recognition of neurobehavioral sequelae of cancer and its treatment. Current understanding of the incidence, pathogenesis, and natural history of these neurobehavioral abnormalities is limited and considerable individual variation in the presence and severity of these complications has been noted. Central nervous system (CNS) abnormalities associated with childhood cancer and its treatment have been demonstrated on at least three levels which may be interrelated: neurobehavioral abnormalities, brain imaging abnormalities, and neurotransmitter abnormalities. Patients will be randomized to either clonidine or placebo. Study medication will be administered in a double blind fashion beginning with a four-week dose titration period followed by a four-week maintenance period. Total duration of dosing is 18 weeks. Patients who derive a benefit from clonidine administration may continue for an additional 30 weeks of therapy. PK samples will be collected at weeks 9 and 18.