Gefitinib-d6 is intended for use as an internal standard for the quantification of gefitinib by GC- or LC-MS. Gefitinib is a selective EGFR-TK inhibitor that blocks the growth of GEO colon cancer, ZR-75-1 and MCF-10A Ha-ras breast cancer, and OVCAR-3 ovarian cancer cell lines with IC50s ranging between 0.2-0.4 µM.1 By interfering with the intracellular kinase domain, gefitinib prevents EGFR autophosphorylation and prevents downstream signal transduction. Formulations containing gefitinib were previously used to treat advanced (or recurrent) non-small cell lung cancer. However, the FDA retracted its general approval when a phase III trial failed to demonstrate an overall survival benefit.2 Formulations containing gefitinib appear to be most efficacious in treating certain EGFR gene mutations prevalent in Asian populations.3,4
1.Ciardiello, F., Caputo, R., Bianco, R., et al.Antitumor effect and potentiation of cytotoxic drugs activity in human cancer cells by ZD-1839 (Iressa), an epidermal growth factor receptor-selective tyrosine kinase inhibitorClin. Cancer Res.6(5)2053-2063(2000) 2.Gerber, D.E.EGFR inhibition in the treatment of non-small cell lung cancerDrug Dev. Res.69(6)359-372(2008) 3.Yang, C.T., Hung, J.Y., Lai, C.L., et al.Gefitinib as first-line therapy for advanced or metastatic non-small cell lung cancer patients in southern TaiwanKaohsiung J. Med. Sci.26(1)1-7(2010) 4.Uruga, H., Kishi, K., Fujii, T., et al.Efficacy of gefitinib for elderly patients with advanced non-small cell lung cancer harboring epidermal growth factor receptor gene mutations: A retrospective analysisIntern. Med.49(2)103-107(2010)