PKU Response to Liver Cell Transplant as Measured by Phe Conversion

Whole Body Turnover Studies of 1-13C Phe in Patients with Phenylketonuria

Protocol Description

The purpose of this research is to measure how the body changes the protein phenylalanine (Phe) to tyrosine before and after liver cell transplant. The reason some people are not able to convert Phe to tyrosine is that they are born with a genetic disease called phenylketonuria (PKU). In people with PKU, an enzyme that does not work properly causes an accumulation of Phe that can lead to intellectual disability and central nervous system problems.

Eligibility Criteria

Individuals who will undergo liver cell transplantation through the related study, Hepatocyte Transplantation for Phenylketonuria, are eligible to participate in this program.
Males and Females: Ages 14-55 years


To measure how the body changes phenylalanine to tyrosine, participants will be given a Carbon-13 Phenylalanine Test at various intervals: twice before liver cell transplant, a month after the final infusion of liver cells, 3 months after the final infusion and every 3 months after for up to 24 months.
Visits: None beyond visits conducted for the liver cell transplant study.
Duration: Dependent on availability of donor cells.

Status: Open only to participants in the Hepatocyte Transplantation for Phenylketonuria study

Source(s) of Support

National Institutes of Health

Primary Investigator

Gerard Vockley, MD, PhD

Contact Information

For more information about the study or enrollment, please contact: 
Jessica Lindenberger, MSN, CRNP, FNP-C