Kinetic parameters for the metabolism of ebastine, hydroxyebastine, and carebastine in recombinant human P450s
The values are estimated from nonlinear least regression analysis using WinNonlin.
Kinetic Parameters | Vmax | Km | Vmax/Km | ||
|---|---|---|---|---|---|
| pmol/min/pmol P450 | μM | μl/min/pmol P450 | |||
| CYP3A4 | Ebastine | ||||
| Dealkylation | 3.34 | 7.67 | 0.44 | ||
| Hydroxylation | 0.12 | 6.86 | 0.02 | ||
| Hydroxyebastine | |||||
| Dealkylation | 7.99 | 7.63 | 1.05 | ||
| Carboxylation | 1.10 | 3.48 | 0.32 | ||
| Carebastine | |||||
| Dealkylation | 0.60 | 3.85 | 0.16 | ||
| CYP3A5 | Ebastine | 0.74 | 5.56 | 0.13 | |
| Dealkylation | |||||
| Hydroxylation | 0.14 | 2.33 | 0.06 | ||
| Hydroxyebastine | |||||
| Dealkylation | 3.09 | 21.9 | 0.14 | ||
| Carboxylation | 0.79 | 13.6 | 0.06 | ||
| CYP2J2 | Ebastine | ||||
| Hydroxylation | 8.20 | 18.3 | 0.45 | ||
| Hydroxyebastine | |||||
|
| Carboxylation | 9.86 | 0.75 |
| |