AZD9291 First Time In Patients Ascending Dose Study

Inclusion Criteria: * Provision of signed and dated, written informed consent prior to any study specific procedures, sampling and analyses * Aged at least 18 years. Patients from Japan aged at least 20 years. * Histological or cytological confirmation diagnosis of Non Small Cell Lung Cancer (NSCLC). * Radiological documentation of disease progression while on a previous continuous treatment with an EGFR TKI e.g. gefitinib or erlotinib (with the exception of 1st line expansion cohort). In addition other lines of therapy may have been given. All patients must have documented radiological progression on the last treatment administered prior to enrolling in the study. * Patients (with the exception of 1st line expansion cohort) must fulfil one of the following: * Confirmation that the tumour harbours an EGFR mutation known to be associated with EGFR TKI sensitivity (including G719X, exon 19 deletion, L858R, L861Q) OR * Must have experienced clinical benefit from EGFR TKI, according to the Jackman criteria (Jackman et al 2010) followed by systemic objective progression (RECIST or WHO) while on continuous treatment with EGFR TKI. * Previous treatment with a single-agent EGFR TKI (e.g. gefitinib or erlotinib). * Females should be using adequate contraceptive measures, should not be breast feeding and must have a negative pregnancy test prior to start of dosing or evidence of non-child bearing potential. * Male patients should be willing to use barrier contraception. * For 1st…