Table 2.
Parameter Estimates of Final Population Pharmacokinetic Model
| Bootstrap Estimates a | |||
|---|---|---|---|
| Parameter | NONMEM Estimate | Median | 95%CI |
| Fixed effect | |||
| CL/F, L/day | 0.532 | 0.532 | 0.500‐0.569 |
| V1/F, L | 8.39 | 8.39 | 7.97‐8.85 |
| Ka (1/day) | 0.409 | 0.410 | 0.354‐0.481 |
| Weight, kg on CL/F | 0.806 | 0.809 | 0.594‐1.04 |
| RBCT burden (units/24 weeks) on CL/F | −0.0118 | −0.0120 | −0.0186 to −0.00544 |
| Albumin, g/L on CL/F | −0.881 | −0.886 | −1.21 to −0.519 |
| Weight, kg on V1/F | 0.705 | 0.718 | 0.495‐0.916 |
| RBCT burden (units/24 weeks) on V1/F | −0.0141 | −0.0141 | −0.0189 to −0.00921 |
| Random effect | |||
| Interindividual variability of CL/F (%) | 34.7 | 34.1 | 28.2‐44.4 |
| Interindividual variability of V1/F (%) | 27.6 | 27.2 | 18.1‐36.2 |
| Residual variability (%) | 20.8 | 20.6 | 16.9‐25.2 |
CI, confidence interval; CL/F, apparent clearance; Ka, absorption rate constant; NONMEM, nonlinear mixed‐effects modeling software; RBCT, red blood cell transfusion; V1/F, apparent volume of distribution.
a
Estimated from nonparametric bootstrap procedure (1000 successful replicates).