erlotinib + gefitinib + icotinib

Erlotinib, gefitinib, and icotinib are first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) used primarily for the treatment of non-small cell lung cancer (NSCLC) with EGFR mutations. These drugs share a similar quinazoline structure and mechanism of action, competitively binding to the Mg-ATP binding site of the EGFR tyrosine kinase catalytic domain to inhibit EGFR phosphorylation and subsequent signal transduction, resulting in antitumor activity. While these three drugs have similar efficacy profiles for NSCLC treatment, they differ in their pharmacokinetic parameters, toxicity profiles, and regional availability. Erlotinib has the strongest apoptosis induction activity due to its different side-chain structure. Gefitinib and erlotinib are globally available, while icotinib is primarily available in China. Erlotinib is also indicated for use in combination with gemcitabine for treating locally advanced, unresectable, or metastatic pancreatic cancer.