Comparison of pharmacokinetics of radiolabeled monoclonal antibody UJ13A in patients and animal models.

The antigen to which the monoclonal antibody UJ13A binds is expressed by normal primate brain and most tumors of neuroectodermal origin. The antibody has been used in radioimmunologic studies in patients with neuroblastoma and glioma, though the uptake of antibody into tumors is low. Animal models have been sought to allow definition of the parameters that influence tumor uptake. Animals include nude mice, in which xenografted human tumors can be studied, and marmosets, in which the primate response to exposure to murine antibodies can be investigated. This presentation reports the preliminary pharmacokinetic data from studies of mice and marmosets and compares the data with those obtained in patients.