Table 3.
Parameter estimates for tamoxifen and endoxifen basic and final pharmacokinetic model
| Model | Basic | Final | ||
|---|---|---|---|---|
| Parameter | Estimate | RSE | Estimate | RSE |
| k12 (h−1) | 1.96 | 17.9% | 1.90 | 20.2% |
| tlag (h) | 0.459 | 8.8% | 0.455 | 10.4% |
| Q1 (l h−1) | 32.7 | 55.7% | 61.8 | 65.4% |
| Vd tamoxifen (l) | 727 | 8.3% | 753 | 9% |
| CLTAM (l h−1) | 9.34 | 6% | 9.34 | 6.2% |
| CLMET (l h−1) | 0.300 | 17% | 0.324 | 9.8% |
| θ2D6,1 | − | − | 0.262 | 14% |
| θ3A4,1 | − | − | 0.157 | 72% |
| IIV CLTAM (shrinkage) | 37.7% (−0.5%) | 19.4% | 37.8% (−0.5%) | 19.2% |
| IIV Vd tamoxifen (shrinkage) | 26.0% (23.7%) | 53.0% | 26.7% (24.9%) | 53.9% |
| Covariance IIV CLTAM and IIV Vd tamoxifen | 63.7% | 29.9% | 61.2% | 31.2% |
| IIV CLMET (shrinkage) | 55.2% (1.7%) | 12.5% | 25.4% (3.2%) | 19.3% |
| Residual error tamoxifen (shrinkage) | 13.7% (6.3%) | 11.3% | 13.7% (6.2%) | 11.3% |
| Residual error endoxifen (shrinkage) | 18.9% (6.4%) | 10.1% | 18.9% (6.3%) | 10.1% |
| Covariance residual error | 62.2% | 22.6% | 62.2% | 22.6% |
| Objective function | −4953 | −5009 | ||
| Condition number | 51 | 69 | ||
RSE, relative standard error of estimate; Vd, volume of distribution.