Gadobutrol Pharmacokinetic and Safety Study in Pediatric Subjects Aged <2 Years (Term Newborn Infants to Toddlers 23 Months of Age Inclusive)

AUC is a measure of systemic drug exposure, which is obtained by collecting a series of blood samples and measuring the concentrations of drug in each sample. AUC from time 0 (start of injection) to infinity was reported in micromole*hour per liter (micromole*h/L).

Clearance is the volume of the fluid presented to the eliminating organ that is effectively completely cleared of drug per unit time and depends on the rate of elimination. CL of gadobutrol normalized for body weight, was reported in Liter per hour per kilogram (L/(h*kg).

Vss is an estimate of drug distribution independent of the elimination process and is proportional to the amount of drug in the body versus the drug plasma concentration at steady-state.

MRT is the average time that the molecules introduced into the body stay in the body. MRT of Gadobutrol is expressed in hours.

Half-life refers to the elimination of the drug, that is, the time it takes for the blood plasma concentration to reach half the concentration. Terminal elimination half-life of gadobutrol from plasma is expressed in hours and is derived from the terminal slope of the concentration versus time curve.

Simulation is the use of the model to predict data other than observed data, in this case early Gadobutrol plasma concentration after intravenous injection. Plasma concentration serves as a surrogate for efficacy (signal and contrast enhancement) in MRI. C20 was simulated for virtual pediatric subjects with homogenous distribution over age. Simulated median (5th and 95th percentile in parenthesis) gadolinium plasma concentrations for a dose of 0.1 mmol/kg body weight were presented.

Simulation is the use of the model to predict data other than observed data, in this case early Gadobutrol plasma concentration after intravenous injection. Plasma concentration serves as a surrogate for efficacy (signal and contrast enhancement) in MRI. C30 was simulated for virtual pediatric subjects with homogenous distribution over age. Simulated median (5th and 95th percentile in parenthesis) gadolinium plasma concentrations for a dose of 0.1 mmol/kg body weight were presented.

Subjects were referred for MRI of any body region. The primary anatomical area to be evaluated by MRI was assessed. Anatomical Area was recorded prior to gadobutrol injection for the unenhanced MRI procedure and after gadobutrol injection for the gadobutrol-enhanced MRI procedure. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The technical adequacy of the unenhanced image set and the combined unenhanced and enhanced image set was assessed based on the following 4 point scale: 1=Region visualized with artifacts compromising quality and interpretability of images, 2=Only partial evaluation of images possible, region not covered adequately anatomically, 3=Region visualized with artifacts, partially compromising image quality but evaluation and diagnosis still possible, 4=Region clearly visualized, excellent quality. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The technical adequacy of the the unenhanced image set and the combined unenhanced and enhanced image set was assessed based 4-point scale and body region. Four-point scale: 1=Region visualized with artifacts compromising quality and interpretability of images, 2=Only partial evaluation of images possible, region not covered adequately anatomically, 3=Region visualized with artifacts, partially compromising image quality but evaluation and diagnosis still possible, 4=Region clearly visualized, excellent quality. Evaluation was done on pre-injection and combined images.

A qualitative assessment of the overall contrast using the following pre-defined 5-point scale: 1= None (for example, in case of a non-enhancing vessel), 2= Poor, 3= Moderate, 4= Good, 5= Excellent, was done. This parameter was assessed in the postcontrast MRI only, which is evaluated together with the unenhanced, this is why it is called combined. Data for combined MRI set was reported.

A qualitative assessment of the overall contrast using the following pre-defined 5-point scale: 1= None (for example, in case of a non-enhancing vessel), 2= Poor, 3= Moderate, 4= Good, 5= Excellent, was done in the postcontrast MRI only, which is evaluated together with the unenhanced, this is why it is called combined. Data for combined MRI set was reported.

Presence of pathology was assessed for unenhanced and combined MRI sets and recorded as "yes/no". The number of lesions identified for each MRI set was recorded.

Presence of pathology was assessed for unenhanced and combined MRI sets and recorded as "yes/no". The number of lesions identified for each MRI set was recorded. Results per body region were reported.

Presence of pathology included presence of lesions and was recorded as "yes/no". If "yes" the number of subjects with specified lists of lesions and body region was reported. Evaluation was done on pre- injection and combined (pre- and post-injection) images.

Presence of pathology included presence of lesions and was recorded as "yes/no". If "yes" the number of subjects with specified lists of lesions and body region was reported. Evaluation was done on pre- injection and combined (pre- and post-injection) images. Data of subjects with missing number of lesions or at least one lesion in unenhanced and combined MRI sets were reported.

The contrast-enhancement for each lesion or vessel was recorded on a 4-point scale: 1 = None, lesion or vessel is not enhanced; 2 = Moderate, lesion or vessel is weakly enhanced; 3 = Good, lesion or vessel is clearly enhanced; 4 = Excellent, lesion or vessel is clearly and brightly enhanced. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The contrast-enhancement for each lesion or vessel was recorded on a 4-point scale: 1 = None, lesion or vessel is not enhanced; 2 = Moderate, lesion or vessel is weakly enhanced; 3 = Good, lesion or vessel is clearly enhanced; 4 = Excellent, lesion or vessel is clearly and brightly enhanced. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The border delineation for each lesion or vessel was recorded on a 4-point scale: 1 = None, no or unclear delineation of the boundary between the lesion or vessel and the surrounding tissue; 2 = Moderate, some aspects of border delineation covered; 3 = Good, almost clear delineation, but not complete on relevant slices; 4 = Excellent, clear and complete delineation.Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The border delineation for each lesion or vessel was recorded on a 4-point scale: 1 = None, no or unclear delineation of the boundary between the lesion or vessel and the surrounding tissue; 2 = Moderate, some aspects of border delineation covered; 3 = Good, almost clear delineation, but not complete on relevant slices; 4 = Excellent, clear and complete delineation.The results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The degree of visualization of internal morphology and structure was recorded on a 3-point scale: 1= Poor, the structure and internal morphology of the lesion or vessel is poorly visible; 2 = Moderate, the structure and internal morphology of the lesion or vessel is visible but sufficient information cannot be obtained; 3 = Good, the structure and internal morphology of the lesion or vessel is sufficiently visible for diagnostic purposes.Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The degree of visualization of internal morphology and structure was recorded on a 3-point scale: 1 = Poor, the structure and internal morphology of the lesion or vessel is poorly visible; 2 = Moderate, the structure and internal morphology of the lesion or vessel is visible but sufficient information cannot be obtained; 3 = Good, the structure and internal morphology of the lesion or vessel is sufficiently visible for diagnostic purposes. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The following diagnoses were reported for both the unenhanced MRI and the combined MRI image sets: Other diagnoses, No lesions/normal, Congenital disease/syndrome, Malignant lesion, Inflammation, Structural malformation, Benign lesion, and Vascular malformation. Evaluation was done on pre- injection and combined (pre- and post-injection) images.

The following diagnoses were reported for both the unenhanced MRI and the combined MRI image sets: Other diagnoses, No lesions/normal, Congenital disease/syndrome, Malignant lesion, Inflammation, Structural malformation, Benign lesion, and Vascular malformation. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

Additional diagnostic gain by the contrast-enhanced image set was assessed on a 3-point scale: scale 1 = Initial diagnosis unchanged, scale 2 = Initial diagnosis changed - improved, i.e. more specific, and scale 3 = Initial diagnosis changed -new diagnosis. Evaluation was done on combined (pre- and post- injection) images.

Additional diagnostic gain by the contrast-enhanced image set was assessed on a 3-point scale: scale 1 = Initial diagnosis unchanged, scale 2 = Initial diagnosis changed - improved, i.e. more specific, and scale 3 = Initial diagnosis changed -new diagnosis. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

Diagnostic confidence based on the unenhanced MRI image sets and thereafter on the combined MRI image sets were assessed on a 3-point scale, as 1 = Not confident, 2 = Confident and 3 = Very confident. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

Diagnostic confidence based on the unenhanced MRI image sets and thereafter on the combined MRI image sets were assessed on a 3-point scale, as 3 = Very confident, 2 = Confident, and 1 = Not confident. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The final diagnosis of the subjects was based on all clinical information available and was provided separately within 4 weeks after MRI. Evaluation was done on pre-injection and combined (pre- and post- injection) images.

The final diagnosis of the subjects was based on all clinical information available and was provided separately within 4 weeks after MRI. Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images. Only subjects with final diagnosis were reported.

The analysis value for change in diagnosis was recorded as "yes/no". Evaluation was done on pre- injection and combined (pre- and post-injection) images.

The analysis value for change in diagnosis was recorded as "yes/no". Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The analysis value for change in diagnosis was recorded as "yes/no". Evaluation was done on pre- injection and combined (pre- and post-injection) images.

The analysis value for change in diagnosis was recorded as "yes/no". Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The analysis value for change in diagnosis was recorded as "yes/no". Evaluation was done on pre- injection and combined (pre- and post-injection) images.

The analysis value for change in diagnosis was recorded as "yes/no". Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The subject management was indicated based on the unenhanced images alone. The analysis value for change in subject management was recorded as "yes/no". Evaluation was done on pre-injection and combined (pre- and post-injection) images.

The subject management was indicated based on the unenhanced images alone. The analysis value for change in subject management was recorded as "yes/no". Results per body regions were reported. Evaluation was done on pre-injection and combined (pre- and post-injection) images.

Change in post-injection test values, such as resulting in a change in subject management or which were not the result of laboratory error and were considered clinically significant by the investigator was reported.

eGFR was calculated based on the Schwartz formula with blood sampling for serum creatinine (Scr) not exceeding 14 days prior to gadobutrol injection. Otherwise, the eGFR was obtained from the original Schwartz formula: eGFR = k * height / Scr where k = 0.45 in term newborn infants < 1 year of age, and k = 0.55 in children up to 13 years of age. If Scr was measured by an enzymatic creatinine method that had been calibrated to be traceable to Isotope dilution mass spectroscopy (IDMS), the updated Schwartz formula was used: eGFR = 0.413*height/Scr.

An Adverse Event (AE) was any untoward medical occurrence in a subject who received study drug. A Serious AE (SAE) was an AE resulting in death, initial or prolonged inpatient hospitalization, life-threatening experience, persistent or significant disability/incapacity, congenital anomaly, or deemed significant for any other reason. The drug-relatedness of AEs was determined by the Investigator based on his/her clinical decision based on all available information, and was based on the question whether there was a "reasonable causal relationship" to the study treatment.