In 1997, for the first time in history, a
monoclonal antibody (mAb), i.e., the chimeric anti-CD20 molecule
rituximab, was approved by the US Food and Drug Administration for use in
cancer patients. Since then, the panel of mAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid
malignancies has not stopped to expand, nowadays encompassing a stunning amount of 15 distinct molecules. This therapeutic armamentarium includes mAbs that target
tumor-associated
antigens, as well as molecules that interfere with
tumor-stroma interactions or exert direct immunostimulatory effects. These three classes of mAbs exert
antineoplastic activity via distinct mechanisms, which may or may not involve immune effectors other than the mAbs themselves. In previous issues of OncoImmunology, we provided a brief scientific background to the use of mAbs, all types confounded, in
cancer therapy, and discussed the results of recent clinical trials investigating the safety and efficacy of this approach. Here, we focus on mAbs that primarily target malignant cells or their interactions with stromal components, as opposed to mAbs that mediate
antineoplastic effects by activating the immune system. In particular, we discuss relevant clinical findings that have been published during the last 13 months as well as clinical trials that have been launched in the same period to investigate the therapeutic profile of hitherto investigational
tumor-targeting mAbs.