Table 2.
Parameter estimates and bootstrap confidence intervals for the population pharmacokinetic model
| Original dataset | Bootstrap result | |||
|---|---|---|---|---|
| Parameter | Estimate (±1.96 × SE) | Median (95% CI) | ||
| CL (L/h) | 0.391 | (0.375 to 0.407) | 0.390 | (0.375 to 0.407) |
| CYP2C9 *2 on CL | −0.147 | (−0.234 to −0.0604) | −0.147 | (−0.215 to −0.0410) |
| CYP2C9 *3 on CL | −0.400 | (−0.488 to −0.312) | −0.400 | (−0.483 to −0.301) |
| Vc (L) | 7.79 | (7.24 to 8.34) | 7.80 | (7.01 to 8.35) |
| LBM on Vd | 1.05 | (0.695 to 1.40) | 1.06 | (0.746 to 1.41) |
| Q (L/h) | 1.24 | (0.948 to 1.53) | 1.24 | (1.00 to 1.68) |
| Vp (L) | 2.73 | (2.20 to 3.26) | 2.72 | (2.22 to 3.49) |
| Ka (/h) | 2.00 | (1.38 to 2.62) | 2.05 | (1.44 to 2.84) |
| DT (h) | 1.91 | (1.86 to 1.96) | 1.91 | (1.83 to 1.94) |
| F | 0.425 | (0.367 to 0.483) | 0.423 | (0.364 to 0.481) |
| ωCL (CV%) | 21.3 | (18.4 to 23.9) | 21.0 | (18.2 to 23.5) |
| ωVd (CV%) | 17.2 | (13.4 to 20.3) | 17.1 | (14.0 to 20.0) |
| ωKa (CV%) | 131 | (68.1 to 201) | 130 | (81.5 to 193) |
| ω2 F | 2.03 | (1.46 to 2.60) | 2.00 | (1.45 to 2.62) |
| ωKa‐ωF | 0.243 | (0.0269 to 0.459) | 0.262 | (0.0421 to 0.482) |
| σ (CV%) | 12.3 | (11.3 to 13.2) | 12.3 | (11.4 to 13.2) |
CI, confidence interval; CL, apparent clearance; CLpop, population mean of apparent clearance; DT, duration of meloxicam entry into the central compartment from the absorption compartment by zero‐order rate; F, fraction of the dose absorbed through the zero‐order absorption process; Ka, first‐order absorption rate constant; LBM, lean body mass; n*2, number of CYP2C9*2 alleles; n*3, number of CYP2C9*3 alleles; Q, apparent intercompartmental clearance; tlag, absorption lag time for meloxicam entry into the central compartment from the absorption compartment with the first‐order rate; Vc, apparent volume of distribution in the central compartment; Vcpop, population mean of apparent volume of distribution in the central compartment; Vp, apparent volume of distribution in the peripheral compartment; ωCL, interindividual variability of CL; ω2 F, interindividual variability of F; ωKa, interindividual variability of Ka; ωKa‐ωF, correlation coefficient between interindividual variability of Ka and that of F; ωVd, interindividual variability of Vd; σ, residual variability.
DT and tlag were set to the same value. Eta‐shrinkage: CL, 1.89%; Vc, 8.81%; Ka, 12.0%; F, 6.30%. Epsilon‐shrinkage: 13.7%. Calculations: tlag = DT (h). The final population pharmacokinetic equation was , where .