Observed/predicted plasma L-citrulline concentration (μmol/L) time profiles.
Solid black lines represent predicted plasma L-citrulline concentrations. Dotted black lines represent 50 μmol/L and 80 μmol/L concentrations and reflect the target trough plasma concentrations. Black dots are the observed L-citrulline concentrations (μmol/L) collected at study time points (i.e. at baseline and trough prior to the 12Five of the six premature infants enrolled in this study provided two urine NOx/Cr levels. The first urine sample from these five subjects was collected before administering the first dose of L-citrulline or shortly after the first dose of L-citrulline was given. The first urine sample collected from one patient was lost. All six premature infants enrolled in this study provided urine NOx/Cr levels from urine collected between 6 ¼ and 7 ½ hours after administering the last study dose of L-citrulline. There was no difference between the urine NOx/Cr levels (median 25.8, IQR 22–44) obtained as a baseline and the urine NOx/Cr levels obtained after the last dose of L-citrulline (median 36, IQR 27–46.6) for the combined group of 5 subjects that provided two samples (p = 0.89). When considering values for each of the individual subjects, as shown in Fig. 