Nationwide Children’s Hospital announced today its involvement in an expanded access program for sapropterin dihydrochloride, or sapropterin, an investigational treatment for phenylketonuria (PKU), a rare genetic metabolic disorder that, if left unmanaged in infants and children, can result in severe mental retardation. Currently, there are eight patients enrolled in the expanded access program at Nationwide Children’s.
Under an expanded access program, the U.S. Food and Drug Administration (FDA) allows early access to drugs that are being developed to treat serious diseases based on certain circumstances.
Individuals with PKU are born with a deficient enzyme called phenylalanine hydroxylase (PAH). With little or no PAH activity, they are unable to metabolize an essential amino acid, called phenylalanine (Phe), which is found in most foods including meat, eggs, dairy, nuts, pasta, bread and all fruits and vegetables. When Phe cannot be metabolized by the body, abnormally-high levels of it accumulate in the blood and are toxic to the brain, potentially causing brain damage that can result in severe mental retardation, seizures, tremors, phobias and general mental and behavioral decline. The only way that PKU patients can manage their disorder is by monitoring their daily intake of Phe; however, compliance with diet is a major problem for PKU patients due to limited food choices, the social limitations of following a strict diet, the poor taste of required formulas, and the availability and cost of specially-produced low-Phe foods.
“By making sapropterin available through expanded access, we hope patients living with PKU will experience lower Phe levels and increased Phe tolerance,” said Kim McBride, MD, MS an investigator in the Center for Molecular and Human Genetics at The Research Institute at Nationwide Children’s Hospital, and a faculty member at The Ohio State University College of Medicine. “Since elevated Phe levels are toxic to the brain and can lead to severe health complications, we are encouraged there may be a new drug treatment designed to manage Phe levels in this patient population.”
Patients with a confirmed diagnosis of hyperphenylalaninemia due to PKU who are older than 8 years of age, not currently enrolled in a clinical study with sapropterin, meet the inclusion criteria, and do not meet any of the exclusion criteria, may be eligible to participate in this program.
It is estimated that approximately 12,000 infants in the United States are born with PKU, and about 50,000 people younger than 40 have the disorder in the developed world. To learn more about PKU, visit www.PKU.com.
Sapropterin (if approved by the FDA, the brand name is expected to be Kuvan™) is an investigational oral small molecule therapeutic for the treatment of PKU. In Phase 3 clinical studies, sapropterin has been shown to lower blood Phe levels and increase Phe tolerance in patients with PKU. A new drug application for sapropterin was submitted to the FDA in May 2007 by BioMarin Pharmaceutical Inc., and if granted priority review status, sapropterin could receive approval by the end of 2007.