Clinical Research Directory

Inclusion Criteria: * Diagnosis of phenylketonuria * Aged 18-65 years * Following a protein-restricted diet with or without medical food within the last 30 days * Routine natural protein intake from food is less than the RDA for protein based on weight (0.8 g/kg/day). * If not consuming animal proteins, recommended protein intake is 115% RDA due to lower bioavailability of plant proteins. * Within ±90 days of starting treatment with pegvaliase at time of study enrollment Exclusion Criteria: * Unable to consent to study * Under age 18 or over age 65 years * Routine natural protein intake is greater than the RDA for protein (0.8 g/kg/d) within the last 30 days. * Females who are currently pregnant or lactating