Fig. 4.

A conceptual illustration of the use of PopPK modeling method to evaluate the immunogenicity effect on systemic clearance with ADA implemented as time-invariant covariate or time-varying covariate. (PK pharmacokinetic(s), ADA anti-drug antibodies; T0, T1, T2, T3 four immunogenicity sampling time-points with T0 representing the baseline; plus sign: ADA+ for a PK sample; minus sign: ADA− for a PK sample; CL clearance; typical value: the estimated value for a typical subject without ADA formation)