Satumomab pendetide (OncoScint, murine) is a kit for In-111.Satumomab is prepared from a murine antibody raised to amembrane-enriched extract of human breast carcinoma hepaticmetastasis. It is a protein, IgG1 κ antibody, and monoclonal.The MAb recognizes tumor-associated glycoprotein(TAG) 72, a mucinlike molecule with a mass greater than100,000 Da.
Satumomab is indicated as a diagnostic aid in determiningthe extent and location of extrahepatic malignant disease in patients with known colorectal and ovarian cancer. Thisagent is used after standard diagnostic tests are completedand when additional information is needed. The cancer mustbe recurrent or previously diagnosed by other methods.
Satumomab localizes to TAG 72. The antibody is chemicallymodified so that it links to radioactive indium-111,which is mixed with the antibody just prior to injection.Imaging techniques will reveal the localization of thesatumomab as “hot spots.” To link the indium-111 to thesatumomab protein, a linker-chelator is used. This is glycyl-tyrosyl-(N,ε-diethylenetriaminepentaacetic acid)-lysinehydrochloride.
