ERBB2 and cancer: The systematization and comparative analysis of the experimental data on the pharmacokinetics of multivalent antibody derivatives of different formats focused on HER2/neu and CEa cancer markers and on angiogenesis markers, such as the ED-B domain of fibronectin, showed that pharmacokinetic characteristics and biodistribution are significantly improved when monovalent antibodies are replaced with bivalent (multivalent) varieties [9].