Pharmacokinetic Characteristics of 86Y-CHX-A″-DTPA-Panitumumab in Female Athymic (NCr) nu/nu Mice
| Pharmacokinetic characteristic | LS-174T | PC-3 | A431 |
|---|---|---|---|
| Relative in vitro expression* | 62.5 | 150.9 | 2,072.2 |
| Relative in vivo expression | + | +-++ | +++ |
| Blood clearance (h) | |||
| Half-life of α-phase | 3.7 ± 1.7 | 2.7 ± 1.2 | 3.1 ± 1.3 |
| Half-life of β-phase | 58.4 ± 15.3 | 69.2 ± 14.4 | 73.9 ± 13.0 |
| Blood AUC[0→4] (%ID·d·g−1) | 31.4 ± 1.5 | 30.0 ± 2.2 | 32.3 ± 2.2 |
| Tumor AUC[0→4] (%ID·d·g−1) | 96.8 ± 5.6 | 61.1 ± 3.7 | 65.3 ± 3.2 |
| Tumor PET AUC[0→3] (%ID·d/cm3) | 72.4 ± 5.3 | 38.8 ± 2.8 | 51.2 ± 2.9 |
| Tumor PET AUC[0→3] (%ID·d/cm3)† | 23.2 ± 3.7 | 21.7 ± 1.0 | 26.3 ± 1.9 |
| Tumor AUC[0→4]:blood AUC[0→4] | 3.1 | 2.0 | 2.0 |
| Tumor AUMC[0→4] (%ID·d2.g−1) | 262.5 ± 14.9 | 171.9 ± 10.3 | 179.9 ± 8.8 |
| Tumor MRT (d) | 2.7 | 2.8 | 2.7 |
↵* Mean fluorescence intensity from flow cytometry cell-binding studies as measure of relative in vitro expression.
↵† Receptor-blocking studies performed by coinjecting 0.1 mg of panitumumab with radiotracer. Values obtained from blocking studies were significantly lower than those from unblocked studies (P < 0.05), demonstrating receptor-mediated accumulation in tumors.
Data are adapted from Ray et al. (25). Data represent mean values from 3 to 6 determinations.