达可替尼 (Vizimpro)

概览

Dacomitinib is a medication used to treat non small cell lung cancer with EGFR exon 19 deletion of exon 21 L858R substitution.

作用机制

Dacomitinib is an irreversible small molecule inhibitor of the activity of the human epidermal growth factor receptor (EGFR) family (EGFR/HER1, HER2, and HER4) tyrosine kinases. It achieves irreversible inhibition via covalent bonding to the cysteine residues in the catalytic domains of the HER receptors. The affinity of dacomitinib has been shown to have an IC50 of 6 nmol/L. The ErbB or epidermal growth factor (EGF) family plays a role in tumor growth, metastasis, and treatment resistance by activating downstream signal transduction pathways such as such as Ras-Raf-MAPK, PLCgamma-PKC-NFkB and PI3K/AKT through the tyrosine kinase-driven phosphorylation at the carboxy-terminus. Around 40% of cases show amplification of EGFR gene and 50% of the cases present the EGFRvIII mutation which represents a deletion that produces a continuous activation of the tyrosine kinase domain of the receptor.

适应症

Dacomitinib is indicated as the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) exon 19 deletion or exon 21 L858R substitution mutations as verified by an FDA-approved test. Lung cancer is the leading cause of cancer death and NSCLC accounts for 85% of lung cancer cases. From the cases of NSCLC, approximately 75% of the patients present a late diagnosis with metastatic and advanced disease which produces a survival rate of 5%. The presence of a mutation in EGFR accounts for more than the 60% of the NSCLC cases and the overexpression of EGFR is associated with frequent lymph node metastasis and poor chemosensitivity.

• Metastatic Non-Small Cell Lung Cancer