THE CLINICAL TRIAL
PKU, or phenylalanine hydroxylase (PAH) deficiency, is a genetic disorder affecting approximately 70,000 diagnosed patients in the regions of the world where BioMarin operates and is caused by a deficiency of the enzyme PAH. This enzyme is required for the metabolism of Phe, an essential amino acid found in most protein-containing foods. If the active enzyme is not present in sufficient quantities, Phe accumulates to abnormally high levels in the blood and becomes toxic to the brain, resulting in a variety of complications including severe intellectual disability, seizures, tremors, behavioral problems and psychiatric symptoms.
The Phearless Study was a phase 1/2 open-Label, dose escalation study to deter-mine the safety and efficacy of BMN 307, an adeno-associated virus vector-mediated gene transfer of human phenylalanine hydroxylase in subjects with phenylketonuria.