Cary Harding, MD, at Oregon Health & Science University (OHSU), provides an overview of phenylketonuria (PKU).



Toxic levels of the amino acid phenylalanine (Phe) cause PKU, a rare metabolic disease that can result in neurocognitive deficits. Currently, there are two approved treatments for PKU. However, most patients are either unresponsive to current therapies or these options present unacceptable safety risks such as anaphylaxis. Since Phe is present in all sources of natural protein, most patients must strictly adhere to a protein-free diet.

Dr. Harding noted that current treatment options remain limited and still necessitate patients with this rare condition to adhere to a strict phenylalanine-free diet.

A new probiotic therapy, SYNB1984, is in development that may remove the need for patients to adhere to that strict diet.

To learn more about phenylketonuria and other metabolic conditions, visit