Cetuximab Biosimilar, Human EG

Cetuximab, a chimeric (mouse/human) anti-EGFR monoclonal antibody, is an EGFR inhibitor used for the treatment of metastatic colorectal cancer and head and neck cancer. Cetuximab binds to EGFR and turns off the uncontrolled growth in cancers with EGFR mutations. Cetuximab can be used for treatment of KRAS wild type colon cancer but has little or no effect in colorectal tumors harboring a KRAS mutation. Before treatment using Erbitux, it is better to do a diagnosis using the real time PCR companion diagnostic test for KRAS, the therascreen KRAS test. There are four closely related receptor tyrosine kinases in the ErbB family of receptors: EGFR (ErbB-1; HER1 in humans), HER2/c-neu (ErbB-2), Her 3 (ErbB-3) and Her 4 (ErbB-4). Bound by members of the epidermal growth factor family (EGF-family) of extracellular protein ligands, EGFR (epidermal growth factor receptor) located on cell surface sends a signal down the MAPK pathway that includes another protein, KRAS (also spelled K-ras). Mutations affecting EGFR and/or KRAS expression or activity could result in cancer. The mutated KRAS continuously sends a growth signal to the downstream pathway, leading to uncontrollable cell division, even if EGFR has been blocked.