This website is intended for Healthcare Professionals practicing in the U.S.

For your patients with phenylketonuria, your decision today could determine their tomorrow

Phenylketonuria (PKU) is characterized by a deficiency in phenylalanine hydroxylase (PAH) activity resulting in an excess of the amino acid phenylalanine (Phe) in the blood and brain. If not adequately controlled, high levels of Phe become neurotoxic and disrupt normal neurophysiology.1,2

This site has been developed for healthcare professionals who treat people with phenylketonuria (PKU). The site is meant to educate and heighten awareness of the PKU burden of illness, the impact of elevated phenylalanine (Phe), as well as the continued unmet need.1,2


Phe icon

What causes PKU?

Phenylketonuria (PKU) is an autosomal recessive inborn error of phenylalanine (Phe) metabolism, which can have significant neurodevelopment sequelae.1-3

Genetics and Pathophysiology

: Above target Phe range icon

Phenylalanine control diminishes with age

67% of adults with PKU are above guideline Phe target ranges, increasing the severity of neuropsychological symptoms and negatively impacting life trajectory.4

Unmet needs of PKU

PKU symptoms icon

Learn more about PKU symptoms

The effects of high Phe are felt throughout a patient’s life and lead to many typical PKU symptoms.

Rethink PKU challenges

Stay connected with the latest PKU information

Register below to connect with a BioMarin representative, learn about upcoming PKU events and news, or request a peer-to-peer discussion.

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  1. Ashe K, Kelso W, Farrand S, et al. Psychiatric and cognitive aspects of phyenylketonuria: the limitations of diet and promise of new treatments. Front Psychiatry. 2019;10:561. doi:10.3389/fpsyt.2019.00561.
  2. Brown CS, Lichter-Konecki U. Phenylketonuria (PKU): a problem solved? Mol Genet Metab Rep. 2016;6:8-12.
  3. Gentile JK, Ten Hoedt AE, Bosch AM. Psychosocial aspects of PKU: hidden disabilities—a review. Mol Genet Metab. 2010;99(suppl 1):S64-S67.
  4. Jurecki ER, Cederbaum S, Kopesky J, et al. Adherence to clinic recommendations among patients with phenylketonuria in the United States. Mol Genet Metab. 2017;120(3):190-197.
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