Administration of sapropterin: how do you take it?
Research type
Research Study
Full title
Administration of sapropterin: is patient practice associated with best efficacy?
IRAS ID
361954
Contact name
Anita MacDonald
Contact email
Sponsor organisation
Birmingham Women's and Children's NHS Foundation Trust
Clinicaltrials.gov Identifier
N/A, N/A
Duration of Study in the UK
0 years, 6 months, 0 days
Research summary
Sapropterin, a synthetic version of tetrahydrobiopterin, is the first UK pharmaceutical treatment approved for Phenylketonuria (PKU). It lowers blood phenylalanine (Phe) levels and increases Phe tolerance in a subset of around 30% of patients. It works by enhancing residual enzyme activity. Overall, limited attention is given to the way that sapropterin is administered. In clinics, it is recorded that the dose of medication is taken, but the timing of administration or if the drug is taken with or without food may remain unchecked. Sapropterin has a low efficiency of uptake and retention in the body. Patients with PKU may not take sapropterin in a manner that optimises its bioavailability. In the pharmaceutical ‘summary of product characteristics’, it is recommended that
sapropterin tablets should be administered with a meal, taken as a single daily dose, the same time each day, preferably in the morning. There is now increasing evidence to show that its efficacy may be increased if taken twice daily. We aim to conduct a patient questionnaire to examine sapropterin administration to patients in the UK, in order to make recommendations to improve practical methods of administering the drug. This will improve Phe tolerance and blood Phe control.REC name
London - Brighton & Sussex Research Ethics Committee
REC reference
25/PR/1344
Date of REC Opinion
22 Oct 2025
REC opinion
Further Information Favourable Opinion