Skip to main content
Fig. 3 | Orphanet Journal of Rare Diseases

Fig. 3

From: Long-term efficacy and safety of sapropterin in patients who initiated sapropterin at < 4 years of age with phenylketonuria: results of the 3-year extension of the SPARK open-label, multicentre, randomised phase IIIb trial

Fig. 3

Study design. BL indicates the time point for baseline Phe levels for the ‘sapropterin continuous’ and ‘sapropterin extension’ groups in the SPARK Extension Study. BL was defined as the Day 1 of receiving sapropterin treatment in the 26-week SPARK study for the ‘sapropterin continuous’ group; for the ‘sapropterin extension’ group, baseline was defined as Day 1 of the SPARK Extension study, when patients started to receive sapropterin treatment on enrolment in the extension study. *A defined level of Phe tolerance consistent with a diagnosis of PKU, ≥ 2 previous blood Phe concentrations ≥ 400 μmol/L obtained on two separate occasions. †BH4 responsiveness defined as a decrease of > 30% in Phe concentrations following a 20 mg/kg BH4 challenge of at least 24 h. Alternatively, 75% of the last four assessed values of Phe concentrations (either from venous blood or dry blood spot) should have been maintained in the therapeutic range. BH4 tetrahydrobiopterin, BL baseline, HPA hyperphenylalaninaemia, Phe phenylalanine, PKU phenylketonuria, R randomisation

Back to article page

Orphanet Journal of Rare Diseases

ISSN: 1750-1172