Phase II Single Arm Study of AZD9291 to Treat NSCLC Patients in Asia Pacific

Inclusion Criteria: * Aged at least 18 years. Patient from Asia Pacific will be enrolled only. * Locally advanced or metastatic NSCLC, not amenable to curative surgery or radiotherapy. * Radiological documentation of disease progression on the last treatment administered prior to enrolling in the study: following 1st line EGFR TKI treatment but who have not received further treatment OR following prior therapy with an EGFR TKI and a platinum-based doublet chemotherapy. Patients may have also received additional lines of treatment. * Documented EGFR mutation (at any time since the initial diagnosis of NSCLC) known to be associated with EGFR TKI sensitivity (including G719X, exon 19 deletion, L858R, L861Q). * Patients must have central confirmation of tumour T790M mutation positive status from a biopsy sample taken after confirmation of disease progression on the most recent treatment regimen. * World Health Organisation (WHO) performance status 0-1 with no deterioration over the previous 2 weeks and a minimum life expectancy of 12 weeks. * At least one lesion, not previously irradiated and not chosen for biopsy during the study screening period, that can be accurately measured at baseline as ≥10mm in the longest diameter (except lymph nodes which must have short axis ≥15mm) with computerised tomography (CT) or magnetic resonance imaging (MRI) which is suitable for accurate repeated measurements. * Females of child-bearing potential using contraception and must have a negative pregnancy test. Exclusion Criteria: * Treatment with an EGFR-TKI (eg, erlotinib, gefitinib, icotinib or afatinib) within 8 days or approximately 5x half-life of study entry; any cytotoxic chemotherapy, investigational agents or other anticancer drugs within 14 days of study entry; previous treatment with AZD9291 or a 3rd generation EGFR TKIs; Major surgery within 4 weeks of study entry; radiotherapy treatment to more than 30% of the bone marrow or with a wide field of radiation within 4 weeks of study entry; currently receiving treatment with potent inhibitors or inducers of CYP3A4. * Any unresolved toxicities from prior therapy. * Unstable spinal cord compression or brain metastases. * Severe or uncontrolled systemic diseases, including uncontrolled hypertension and active bleeding diatheses or infection. * Refractory nausea and vomiting, chronic gastrointestinal diseases or bowel resection. * Cardiac disease. * Past medical history of interstitial lung disease, drug-induced interstitial lung disease, radiation pneumonitis which required steroid treatment, or any evidence of clinically active interstitial lung disease. * Inadequate bone marrow reserve or organ function.