John Adams, CEO and President of CanPKU, a Canadian based non profit organization dedicated to promoting awareness and education of phenylketonuria (PKU) recently talked with Rare Disease Report about his organization and the treatment options for PKU.
PKU is a rare, inherited (autosomal recessive ) metabolic disease that results in mental retardation and other neurological problems when treatment is not started within the first few weeks of life. Since people with PKU are missing an enzyme to break down the amino acid phenylalanine, these people cannot eat protein without the amino acid building up which can lead to brain damage and other neurological problems. Most children and adults with PKU must follow a special diet. The PKU diet involves strictly controlling the intake of natural protein (which contains phenylalanine), drinking a synthetic phenylalanine-free protein formula (known as medical food) and eating special low-protein food. The synthetic formula and special low-protein foods are expensive.
In addition, some patients benefit from Biomarin's Kuvan which is a pharmaceutical formulation of BH4, the co-factor for the enzyme phenylalanine hydroxylase (PAH). PAH hydroxylates Phe through an oxidative reaction to form tyrosine. In patients with PKU, PAH activity is absent or deficient. Treatment with Kuvan can activate residual PAH enzyme, improve the oxidative metabolism of Phe, and decrease Phe levels in some patients.