Table 2.
Estimated pharmacokinetic parameters
| Model | Base | Final | ||
|---|---|---|---|---|
| parameter (unit) | estimate | RSE (%) | estimate | RSE (%) |
| V 1 (L) | 4.0 | 6 | 4.1 | 7 |
| BSA on V 1 | – | – | 1.0 | 38 |
| Sex on V 1 | – | – | 0.37 | 34 |
| RTC on V 1 | – | – | 0.41 | 19 |
| k 10 (day −1) | 0.12 | 8 | 0.11 | 8 |
| IgG on k 10 | – | – | 0.50 | 19 |
| CD19 on k 10 | – | – | 0.035 | 27 |
| k 12 (day −1 ) | 0.43 | 5 | 0.42 | 6 |
| k 21 (day −1 ) | 0.26 | 5 | 0.25 | 4 |
| ω V1 | 0.28 | 21 | 0.22 | 25 |
| ω k10 | 0.30 | 12 | 0.24 | 13 |
| ω k12 | – | – | – | – |
| ω k21 | – | – | – | – |
| γ V1 | 0.45 | 12 | 0.33 | 12 |
| γ k10 | 0.11 | 18 | 0.08 | 23 |
| γ k12 | – | – | – | – |
| γ k21 | – | – | – | – |
| σ add (mg l –1 ) | 0.31 | 4 | 0.31 | 4 |
| σ prop (%) | 0.27 | 2 | 0.27 | 2 |
V1, volume of distribution; BSA, body surface area; RTC, rituximab treatment course; k, elimination rate constant; IgG, immunoglobulin G serum concentration (g l–1); CD19, CD19+ (B‐cell) count (mm−3); RSE, residual standard error (standard error/parameter value); ω, interindividual standard deviation; γ, interoccasion standard deviation; σadd, additive residual standard deviation; σprop, proportional residual standard deviation.