A fully human monoclonal agonistic antibody directed against tumor necrosis factor-alpha (TNF-alpha)-related apoptosis-inducing ligand receptor-2 (TRAIL-R2) with potential antitumor activity. Mimicking the natural ligand TRAIL, lexatumumab binds to and activates TRAIL-R2, which may trigger apoptosis in and inhibit the growth of TRAIL-R2-expressing tumor cells. TRAIL-R2, also known as death receptor 5 (DR5), is a member of the TNF receptor family and is expressed on many malignant cell types. or A substance being studied in the treatment of some types of cancer. It binds to a protein called TRAIL-R2 on the surface of some tumor cells, which may kill the tumor cells. Lexatumumab is a type of monoclonal antibody. Also called anti-TRAIL R2 mAb HGS-ETR2 and HGS-ETR2.