- Female or male patients aged 18 years or over with locally advanced or metastatic stage IIIB/IV disease, not suitable for therapy of curative intent or stage IV (metastatic) disease, eligible for gefitinib re-challenge treatment for NSCLC who have already received an EGFR-TKI with a documented complete (CR) or partial response (PR) or stable disease (SD) >12 weeks as the best response to their 1st EGFR-TKI treatment and who have received any subsequent anti-cancer therapy (excluding EGFR-TKIs) treatment, including but not limited to doublet platinum based chemotherapy or docetaxel monotherapy or pemetrexed monotherapy, on which they progressed.