Atezolizumab exposure across pediatric and young-adult cohorts

Infant median covariates

Conditional source fixed-effect preset. Dose amounts are fixed by default; select Recalculate paper regimen to couple weight and dose.

Readouts

Central atezolizumab concentration · ug/mL

Central amount divided by covariate-adjusted central volume; mg/L and ug/mL have equal numerical values.

Exposure (AUC) · ug*day/mL

Continuous integral of central concentration from the selected simulation start, using the supplied initial state.

Systemic clearance · L/day

Fixed-effect clearance scaled by weight, albumin, tumor burden and anti-drug-antibody status.

Central distribution volume · L

Central volume scaled by weight and albumin; age cohort is context rather than an age covariate.

Study purpose

• How do the selected cohort covariates and explicitly chosen dose policy change central exposure?

Assumptions

• Exposure uses fixed effects; population variability and prediction intervals are not modeled.
• Age group sets covariate ranges and dosing. Age and maturation are not modeled in the PK equations.
• The infant cohort had two participants, aged seven months or older. Covariate ranges do not capture individual patient combinations.
• “Keep selected dose” preserves mg after edits. “Recalculate paper regimen” uses 15 mg/kg (maximum 1,200 mg) for children or 1,200 mg for young adults.
• Both dosing modes use 10 infusions, 21 days apart: 60 minutes for the first, then 30 minutes.
• The 6 µg/mL benchmark comes from preclinical data. Its indicator shows current concentration, not trough exposure, efficacy, or population target attainment.
• AUC accumulates from the selected start time and initial state; earlier exposure is excluded.
• Random effects, residual error, population exposure distributions, and full published figures are not reproduced. Fitting and server scans are unavailable.