A humanized monoclonal antibody directed against the human alpha v integrin subunit with potential antiangiogenic and antineoplastic activities. Abituzumab, a chimeric antibody which includes the antigen binding sites of the anti-integrin mouse antibody 17E6, binds to and inhibits the activity of alphaVbeta3 integrin (vitronectin receptor); this may result in the inhibition of endothelial cell-cell interactions, endothelial cell-matrix interactions, and integrin-mediated tumor angiogenesis and metastasis in alphavbeta3-expressing tumor cells. AlphaVbeta3 integrin, a cell adhesion and signaling receptor, is expressed on the surface of tumor vessel endothelial cells and plays a crucial role in endothelial cell adhesion and migration.