Topotecan pharmacokinetic parameters after administration of topotecan hydroxy acid
| Pharmacokinetic Parameters | Topotecan Hydroxy Acid | Topotecan Total | ||
|---|---|---|---|---|
| Topotecan alone | Probenecid (600 mg/kg) | Topotecan alone | Probenecid (600 mg/kg) | |
| V c (l/m2) | 1.4 | 0.9 | 1.4 | 0.8 |
| K e (hr−1) | 6.1 | 3.3 | 5.9 | 3.2 |
| t ½ β(hr) | 1.0 | 3.1 | 1.2 | 2.3 |
| Vdss(l/m2) | 1.8 | 1.0 | 2.1 | 1.0 |
| Clsys(l/hr/m2) | 8.8 | 2.8 | 8.1 | 2.7 |
| C max(ng/ml) | 1384.0 | 3258.0 | 1462.0 | 3438.0 |
| Clrenal(l/hr/m2) | – | – | 0.07 ± 0.04# | 0.02 ± 0.01* |
Pharmacokinetic parameters after administration of topotecan hydroxy acid alone and in combination with probenecid (600 or 1200 mg/kg) 30 min before and 3 hr after administration of topotecan are summarized. Renal clearances are presented as mean ± standard deviation. Topotecan total renal clearance (Clrenal) was significantly reduced (P < .05) after coadministration with 600 mg/kg probenecid (*) compared with topotecan alone (#).