Table 4.
Betamethasone population PK parameter estimates along with percent relative standard errors (%RSE)
| Parameter | Definition | Estimate (%RSE) of typical value | Estimate (%RSE) of variance |
|---|---|---|---|
| CL/FIM, L/h | Apparent clearance | 5.95 (8.6) | 0.0210 (13.9) (14.6)* |
| Vp/FIM, L | Apparent central volume | 67.5 (3.2) | 0.0188 (10.7) (13.8)* |
| kaIM, 1/h | First-order absorption rate for IM administration | 0.971 (3.6) | 0.0441 (7.9) (21.2)* |
| kaIMa, 1/h | First-order absorption rate for BET acetate after IM administration | 0.00638 (14.7) | 0.147 (2.1) (39.8)* |
| kaPO, 1/h | First-order absorption rate for PO administration | 1.21 (1.5) | 0.241 (0.8) (52.2)* |
| Fr | Relative bioavailability, Fr = FPO/FIM | 0.935 (9.7) | 0.0182 (8.1) (13.6)* |
| Fra | Relative bioavailability, Fra = FIMa/FIM | 0.819 (9.1) | 0.00773 (0.02) (8.8)* |
| CLD/FIM, L/h | Apparent distributional clearance | 0.173 | NA |
| VT/FIM, L | Apparent volume of peripheral compartment | 4.94 | NA |
| Cov(CL/FIM, Vp/FIM) | Covariance of CL/FIM and Vp/FIM | NA | 0.0155 (37.2) (0.78)* |
| σ2 | Residual error | NA | 0.0211 (0.03) |
*Variance of log-normal distribution expressed as CV%