Afatinib (BIBW2992), an irreversible inhibitor of the ErbB family of tyrosine kinases, downregulates ErbB signalling by binding to the kinase domains of epidermal growth factor receptor (EGFR)/ human epidermal growth factor receptor 2 (HER2) with IC50 of 0.5 nM and 14nM, respectively.
The ErbB receptor tyrosine kinase family consists of four cell surface receptors: ErbB1/ EGFR/HER1, ErbB2/HER2, ErbB3/HER3, and ErbB4/HER4. It has been shown that EGFR and HER2 play important roles in the development and progression of certain aggressive types of cancers and inflammation-associated diseases.
Afatinib was shown to suppress EGF-induced phosphorylation of EGFR and cell proliferation in a variety of EGFR-overexpressing and HER2-expressing cell lines such as A431, NIH-3T3-HER2, NCI-N87 and BT-474 [1].
The component has also been used extensively in various animal models to study the role of EGFR/HER2. Oral administration of afatinib inhibited cancer cell growth and survival and suppress the tumor regression in xenograft and transgenic lung cancer models [2]. In addition, afatinib is identified as EGFR blocker which was approved for the treatment of patients with EGFR-mutated nonsmall cell lung cancer [3].
References:
1.Eskens FA, Mom CH, Planting AS, Gietema JA, Amelsberg A, Huisman H, et al. A phase I dose escalation study of BIBW 2992, an irreversible dual inhibitor of epidermal growth factor receptor 1 (EGFR) and 2 (HER2) tyrosine kinase in a 2-week on, 2-week off schedule in patients with advanced solid tumours. Br J Cancer 2008,98:80-85.
2.Li D, Ambrogio L, Shimamura T, Kubo S, Takahashi M, Chirieac LR, et al. BIBW2992, an irreversible EGFR/HER2 inhibitor highly effective in preclinical lung cancer models. Oncogene 2008,27:4702-4711.
3.Engle JA, Kolesar JM. Afatinib: A first-line treatment for selected patients with metastatic non-small-cell lung cancer. Am J Health Syst Pharm 2014,71:1933-1938.