The recommended first line treatment for patients with advanced non-small cell lung cancer (NSCLC), harbouring an activating or sensitising epidermal growth factor receptor (EGFR) mutation is an EGFR tyrosine kinase inhibitor (EGFR-TKI).1,2
Although patients experience a high initial response rate to first-line EGFR-TKIs, most patients with EGFR mutation-positive advanced NSCLC will progress on treatment, with a median progression-free survival range of 9.7–13.1 months.3 The most common mechanism of acquired resistance to EGFR-TKIs is the EGFR T790M mutation, which occurs with an amino acid substitution at position 790 in EGFR, from a threonine (T) to a methionine (M). Studies have shown that the incidence of the EGFR T790M mutation in tumours that have developed resistance to first-generation EGFR-TKIs (erlotinib and gefitinib) ranges from 51 to 68%.4–9
Testing for the T790M mutation is now possible using tissue and plasma samples, and methods similar to those for EGFR mutation testing at the time of primary diagnosis. Visit www.EGFR-mutation.com or www.IDLung.com for more information on EGFR mutation testing at progression.
The treatment landscape for patients with EGFR mutation-positive advanced NSCLC has now changed, with the availability of the first 3rd generation TKI approved for adult patients with locally advanced or metastatic EGFR T790M mutation-positive NSCLC (TAGRISSO [osimertinib]). TAGRISSO is an oral, selective irreversible TKI that targets both EGFR-sensitising mutations and specifically the EGFR T790M mutation while sparing wild-type EGFR. Visit www.tagrisso-global.com for further information.