Erlotinib

Better Known as: Tarceva Marketed By: Genentech, OSI Pharmaceutials, & Roche Major Indication: Pancreatic & Small Cell Lung Cancer Drug Class: EGFR Inhibitor Date of FDA Approval (Expiration): 2005 (2020) 2009 Sales: $1.2 Billion Importance: It is one of the best selling and most effective treatments for several types of cancer. It is an improved version of Iressa. See Pharmaceutical Drugs for more information about other drugs and disorders Mechanism of Action Epidermal Growth Factor Receptors are overexpressed in many types of human carcinomas including lung, pancreatic, and breast cancer, and are often mutated. This overexpression leads to excessive activation of the anti-apoptotic Ras signalling cascade, resulting in uncontrolled DNA synthesis and cell proliferation. Studies have revealed that the is responsible for activating this Ras signaling cascade. Upon binding ligands like Epidermal Growth Factor, EGFR dimerizes and autophosphorylates several tyrosine residues at its C-terminal domain. Upon phosphorylation, EGFR undergoes a conformational change, revealing an additional binding site capable of eliciting downstream activation of other signaling proteins. Erlotinib inhibits the EGFR tyrosine kinase by located within the kinase domain. EGFR uses residues Asp 831, Lys 721, Thr 766, Leu 820, Gly 772, Phe 771, Leu 694, Pro 770, Met 769, Leu 768, Gln 767 & Ala 719 to tightly bind the inhibitor. Unable to bind ATP, EGFR is incapable of autophosphorylating its C-terminal tyrosines, and the uncontrolled cell-proliferation signal is terminated. Pharmacokinetics Tyrosine Kinase Inhibitor Pharmacokinetics VEGFR & KIT Inhibitors EGFR Inhibitors BCR-Abl Inhibitor Parameter Sunitinib (Sutent) Sorafenib (Nexavar) Erlotinib (Tarceva) Gefitinib (Iressa) Lapatinib (Tykerb) Imatinib (Gleevec) Nilotinib (Tasigna) Dasatinib (Sprycel) Tmax (hr) 8 8.3 2.0 5.4 4 3.7 3.0 1.0 Cmax (ng/ml) 24.6 460 69.6 130 115 2070 411 124 Bioavailability (%) Variable 29-49 99 59 Variable 98 30 20 Protein Binding (%) 95 99 93 90 99 95 98 96 T1/2 (hr) 83 29 9.4 26.9 9.6 26.6 16.0 3.3 AUC (ng/ml/hr) 1921 11040 20577 3850 1429 4760 10052 461 Dosage (mg) 50 50 150 250 100 400 200 200 Metabolism Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) Hepatic (CYP3A4) For Pharmacokinetic Data References, see: References

spinqualitylabelsall models Erlotinib, also known as Tarceva Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image