Nutrients
Sepiapterin Enables Liberalisation of Natural Protein Intake While Improving Metabolic Control in Adolescents with Phenylketonuria
By Pinto A, Daly A, Vijay S and 2 others.
Abstract
Background
Sepiapterin is a synthetic precursor of tetrahydrobiopterin (BH4) that increases intracellular BH4 availability and has demonstrated greater phenylalanine-lowering efficacy than sapropterin. We evaluated its effect on dietary liberalisation and metabolic control in adolescents with phenylketonuria (PKU).
Methods
Seven adolescents with PKU (median age of commencing sepiapterin: 13 years, range 12-17 years), including five previously responsive to sapropterin, were studied. Median natural protein intake, protein equivalent from protein substitute, and total protein intake were compared during diet-only treatment, sapropterin treatment (where applicable), and after 12 months of sepiapterin. Blood phenylalanine (Phe) and tyrosine (Tyr) concentrations were assessed over 12 months for each treatment period.