Table 2.
Parameter estimates using Monolix® version 4.2 and the effect of single dose activated charcoal on bioavailability and clearance
| Base model | Model 1 – SDAC fF-char | Model 2 – Final SDAC fCL-char | |
|---|---|---|---|
| Mean value (RSE%) | Mean value (RSE%) | Mean value (RSE%) | |
| Structural model (θ) | |||
| ts,lag (h) | 1 (fixed) | 1 (fixed) | 1 (fixed) |
| Ka (h−1) | 1.06 (83) | 1.02 (95) | 0.895 (42) |
| F | 1 (fixed) | – | 1 (fixed) |
| V (l) | 5130 (15) | 4730 (14) | 5340 (18) |
| CL (l h−1) | 151 (20) | 144 (19) | – |
| fF-char | – | 0.731 (178) | – |
| θF | – | 1 (fixed) | – |
| fCL-char | – | – | 1.92 (70) |
| θCL | – | – | 130 (34) |
| Between subject variance (ω) | |||
| ts,lag | 0.849 (45) | 0.794 (51) | 0.922 (52) |
| Ka | 1.51 (139) | 1.63 (104) | 1.02 (77) |
| F | 0.321 (40) | 0.275 (43) | 0.303 (48) |
| V | 0.087 (95) | 0.146 (80) | 0.085 (219) |
| CL | 0.18 (77) | 0.109 (134) | 0.126 (103) |
| Coefficient of variation for proportional residual error (CV%) | 11.8 | 11.9 | 11.7 |
| Objective function (−2 log-likelihood value) | −207.10 | −208.09 | −212.04 |
ts,lag = shifted dose time (estimated time plus 1 h), Ka = absorption rate constant, F = relative bioavailability, V = volume of distribution, CL = clearance, fF-char = fractional effect of SDAC on bioavailability, fCL-char = fractional effect of SDAC on clearance. CL = θCL × fCL-char. F = θF × fF-char.