Question

Please explain in detail the mechanisims by which these biologicals work on a patient with NSCLC?

A) Gefitinib aka Iressa

B) Erlotinib aka Tarceva

C) Afatinib aka Giotrif

Answer 1

A) Gefitinib aka Iressa

Iressa (gefitinib) is a cancer medication that interferes with the growth and spread of cancer cells in the body.Iressa should only be administered under the supervision of a qualified healthcare provider experienced in the use of cancer chemotherapeutic agent.

B) Erlotinib aka Tarceva

Erlotinib specifically targets the epidermal growth factor receptor (EGFR) tyrosine kinase, which is highly expressed and occasionally mutated in various forms of cancer. It binds in a reversible fashion to the adenosine triphosphate (ATP) binding site of the receptor. 2 EGFR molecules need to come together to form a homodimer. These then use the molecule of ATP to trans-phosphorylate each other on tyrosine residues, which generates phosphotyrosine residues, recruiting the phosphotyrosine-binding proteins to EGFR to assemble protein complexes that transduce signal cascades to the nucleus or activate other cellular biochemical processes.

C) Afatinib aka Giotrif

Afatinib is a protein kinase inhibitor that also irreversibly inhibits human epidermal growth factor receptor and epidermal growth factor receptor kinases.This is an irreversible inhibitor of the ErbB family, acting on EGFR (HER1, ErbB1), ErbB2 (HER2) and ErbB4 (HER4). Covalent attachment to cysteine residues in the catalytic domain of EGFR, HER2 and ErbB4 inhibits the tyrosine kinase activity (TKIs) of these receptors, decreasing auto- and transphosphorylation between ErbB dimers, and thus blocking the activity of downstream signalling pathways related to growth and apoptosis suppression. In preclinical models, this has resulted in a reduction in tumour size.