Tixagevimab component serum exposure

Reference gluteal IM, 300 mg

How does 300 mg IM administration produce exposure under the reference covariates? Deterministic conditional exploration.

Readouts

Central serum concentration· ug/mL

Central amount divided by apparent central volume; mg/L equals ug/mL.

Exposure (AUC)· ug*day/mL

Concentration integral from simulation start; interval exposure requires differencing integral values.

Covariate adjusted clearance· L/day

Fixed clearance coefficient under the selected baseline covariates.

Study purpose

• How does 300 mg IM administration produce exposure under the reference covariates?

Interpretation limits

• The total AZD7442 fit is independent of the two component fits; do not add component trajectories or synthesize an unreported cross-analyte population covariance.
• Component parameter identities provisionally follow the supplemental captions. Twenty-six coefficient rows conflict with article Table 1; the opposite component column matches 23 exactly, with three remaining differences. Author adjudication is absent.
• IM dose enters a first-order depot; the fitted IM scaling multiplier can exceed one in the total thigh configuration (approximately 1.017). It is empirical and must not be interpreted as a conserved physical fraction.
• IV scenarios assume one-hour administration. Original infusion duration and component timing are unavailable; no original peak or sequential-infusion claim is made.
• Categorical covariates and route fractions are fixed setup/context, not continuous axes. Body weight changes disposition under the fixed mg schedule.
• The diagnostic disposition half-time uses the slow two-compartment eigenvalue and omits a possible absorption-controlled terminal phase; it is not a population median.
• Original individual data, censored likelihood, fitted effects, bootstrap, VPC, adolescent cohort and clinical protection are not reconstructed.
• Supplementary-file reuse permission remains unresolved separately from the article license. Source documents and artwork are not distributed; this executable implementation and its figures are independently authored.
• The component identity provisionally follows Supplement Table S4; article Table 1 assigns the component coefficients differently. No author adjudication is available.
• Weight bounds span the 55.6 and 122 kg Figure 4 anchors as an exploratory interval, not a validated joint patient range. The other control bounds are authored 0.5–1.5× default ranges, not confidence intervals.
• The higher-weight context changes weight alone; it does not reproduce every factor of the Figure 4 low-exposure population scenario.
• Changing the start time resets supplied initial states at that start; earlier bolus history is not reconstructed. An overlapping IV infusion contributes only the remaining segment.
• The IV context does not depend on IM absorption or empirical IM scaling. Use an IM context to explore these controls.