Table 2.
Performances of limited sampling strategies for ibrutinib AUC estimation, stratified by the number of concentration–time points and sorted by RMSE (first 6 entries) in the development cohort (n = 85).
| Number of Points | Sampling Strategy | Mean Actual AUC (ng/mL·h) | RMSE (%) | MPE (%) | P20 (%) |
|---|---|---|---|---|---|
| 1 | T6 | 672 | 40.4% | +8.3% | 59% |
| T4 | 672 | 44.6% | +6.0% | 81% | |
| T2 | 672 | 45.3% | −11.9% | 62% | |
| T1 | 672 | 54.8% | +28.8% | 72% | |
| T0.5 | 672 | 61.9% | +39.6% | 71% | |
| T0 (LR) * | 672 | 67.9% | +42.7% | 71% | |
| 2 | T1–4 | 672 | 22.8% | −7.2% | 36% |
| T2–4 | 672 | 25.8% | −6.0% | 48% | |
| T1–6 | 672 | 30.0% | −9.1% | 40% | |
| T2–6 | 672 | 30.0% | −12.0% | 48% | |
| T0.5–4 | 672 | 31.6% | +4.2% | 47% | |
| T0.5–6 | 672 | 34.2% | +5.1% | 52% | |
| 3 | T0–1–4 | 672 | 14.5% | +2.2% | 25% |
| T1–4–6 | 672 | 19.2% | −7.9% | 31% | |
| T1–2–4 | 672 | 19.9% | −6.1% | 28% | |
| T0.5–2–6 | 672 | 22.0% | −9.2% | 28% | |
| T0–2–4 | 672 | 22.7% | −1.9% | 29% | |
| T0.5–2–4 | 672 | 22.7% | −2.7% | 31% | |
| 4 | T0–1–2–4 | 672 | 11.0% | −0.3% | 4% |
| T0–1–4–6 | 672 | 13.1% | −0.5% | 18% | |
| T0–0.5–2–4 | 672 | 13.3% | +3.1% | 11% | |
| T0–0.5–1–4 | 672 | 15.3% | +4.1% | 24% | |
| T1–2–4–6 | 672 | 15.7% | −8.2% | 18% | |
| T0.5–2–4–6 | 672 | 17.1% | −4.5% | 16% |
MPE: mean percentage error; P20: proportion of patients with a residual error superior to +/−20%; RMSE: root-mean-square error; * AUC derived from the linear regression (LR) equation of actual ibrutinib AUC and trough concentration of ibrutinib.