Copper Histidine Therapy for Menkes Diseases

Overview

Menkes Disease is a genetic disorder affecting the metabolism of copper. Patient with this disease are both physically and mentally retarded. Menkes disease is usually first detected in the first 2-3 months of life. Infant males born with the disease fail to thrive, experience hypothermia, have delayed development, and experience seizures. These infants also have characteristic physical features such as changes of their hair and face. Females may also have changes in hair and skin color, but rarely have significant medical problems. Appropriate treatment of Menkes Disease requires that the disease be diagnosed early and treatment started before irreversible brain damage occurs. The aim of treatment is to bypass the normal route of absorption of copper through the gastrointestinal tract. Copper must then be delivered to brain cells and be available for use by enzymes. Copper histidine is a copper replacement that can be injected directly into the body to avoid absorption through the gastrointestinal tract. However, studies have shown the genetic abnormalities causing Menkes disease cannot simply be corrected by copper replacement injections. The genetic abnormality causing Menkes disease can vary in its severity. Patients with a genetic abnormality that may still permit some production of the enzymes required to process copper may receive benefit from early treatment with copper replacement. However, patients with severe abnormalities of the genes responsible for copper metabolism may receive no benefit from copper replacement. The purpose of this study is to continue to evaluate the effects of early copper histidine in Menkes disease patients and to correlate specific molecular defects with responses to treatment.

Menkes disease is an X-linked recessive neurodegenerative disorder caused by defects in a gene that encodes an evolutionarily conserved copper-transporting ATPase (ATP7A). Several issues must be addressed in configuring therapeutic strategies for this disorder: (a) affected infants must be identified and treatment commenced very early in life before irreparable neurodegeneration occurs, (b) the block in intestinal absorption of copper must be bypassed, (c) circulating copper must be delivered to the brain, and (d) copper must be available to enzymes within cells that require it as a cofactor. Very early, pre-symptomatic therapy with copper injections has been associated with improved overall survival and, in some patients - based on their molecular defects, with vastly better neurological outcomes in comparison to the usual natural history of this disorder. The purpose of this study is to continue to provide early copper treatment to other newborn infants diagnosed as having Menkes disease.