Evaluation of limited blood sampling in a preceding Tc-99m-labeled diagnostic study to predict the pharmacokinetics and myelotoxicity of Re-186-cMAb U36 radioimmunotherapy
Dr. Colnot et al., Evaluation of limited blood sampling in a preceding Tc-99m-labeled diagnostic study to predict the pharmacokinetics and myelotoxicity of Re-186-cMAb U36 radioimmunotherapy, J NUCL MED, 42(9), 2001, pp. 1364-1367
Citations number
5
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging","Medical Research Diagnosis & Treatment
Re-186-labeled chimeric monoclonal antibody U36 (cMAb U36) was recently eva
luated in a phase I dose escalation study in head and neck cancer patients.
All 13 patients received Tc-99m-labeled cMAb U36 before Re-186-cMAb U36 ra
dioimmunotherapy. The aim of this study was to evaluate the suitability of
multiple or limited blood sampling to predict clearance, red marrow absorbe
d dose, and myelotoxicity of Re-186-cMAb U36. Methods: Population pharmacok
inetics of Re-186-cMAb U36 were analyzed with a nonparametric expectation a
lgorithm (NPEM 2) and used for Bayesian analysis of individual patient data
to predict cMAb U36 clearance. Results: Re-186-cMAb U36 clearance was most
accurately predicted (r = 0.91, P < 0.001) with limited sampling for sampl
e points 4 and 72 h after administration of Re-186-cMAb U36. These predicti
ons were less accurate with Tc-99m-cMAb U36 (r = 0.51, P = 0.078 for multip
le sampling; r = 0.47, P = 0.104 for sampling at 4 and 21 h after administr
ation), Thrombocytopenia was found to be correlated with the red marrow abs
orbed dose and was equally well predicted by limited blood sampling after a
dministration of Tc-99m-cMAb U36 (r = 0.81, P < 0.01) or Re-186-cMAb U36 (r
= 0.79, P < 0.01). Conclusion: Limited sampling seems useful to predict ph
armacokinetics and myelotoxicity of Re-186-cMAb U36.