Inclusion Criteria

Inclusion Criteria at screening (Visit 1) and at Start of Study Treatment (Visit 2):

- Provision of informed consent prior to any study specific procedures.

- Histologically or cytologically confirmed NSCLC with an activating sensitising EGFR
TK mutation as it was determined before starting the first gefitinib treatment by
using a well-validated and robust methodology: adenocarcinoma, including
Bronchoalveolar Carcinoma (BAC), squamous cell carcinoma, large cell carcinoma,
adenosquamous carcinoma or undifferentiated carcinoma or not-otherwise specified
NSCLC.

- 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 gefitinib with a documented complete (CR) or
partial response (PR) or stable disease (SD) >12 weeks as the best response to
their 1st gefitinib treatment and progressing during or after a subsequent
anti-cancer therapy (excluding EGFR-TKIs) treatment, including but not limited
to doublet platinum based chemotherapy or docetaxel monotherapy or pemetrexed
monotherapy.

- Measurable disease defined as at least one lesion, not previously irradiated,
that can be accurately measured at baseline as ≥ 10 mm in the longest diameter
(except lymph nodes which must have short axis ≥ 15 mm) with spiral CT or MRI
and which is suitable for accurate repeated measurements.

- WHO / ECOG / Zubrod performance status 0-2.

Exclusion Criteria:

- Known severe hypersensitivity to gefitinib or any of the excipients of the product

- Prior EGFR TKIs except gefitinib followed by subsequent anti-cancer treatment
(including chemotherapy and excluding EGFR-TKIs).

Previous adjuvant chemotherapy is allowed. Prior surgery or radiotherapy must be completed
more than 6 months before start of study treatment. Palliative radiotherapy must be
completed at least 4 weeks before start of study treatment with no persistent radiation
toxicity.

- Progression disease or stable disease (SD) <12 weeks as best response to the 1st line
treatment with gefitinib

- Not progressing during or after the last anti-cancer treatment.

- Considered to require radiotherapy to the lung at the time of study entry or in the
near future

- Past medical history of interstitial lung disease, drug-induced interstitial disease,
radiation pneumonitis which required steroid treatment or any evidence of clinically
active interstitial lung disease

- Pre-existing idiopathic pulmonary fibrosis evidenced by CT scan at baseline

- Insufficient lung function as determined by either clinical examination or an
arterial oxygen tension (PaO2) of < 70 Torr

- Known or suspected brain metastases or spinal cord compression, unless treated with
surgery and/or radiation and stable without steroid treatment for at least 4 weeks
prior to the first dose of study medication

- Any unresolved chronic toxicity greater than CTC grade 2 from previous anticancer
therapy

- Concomitant use of known CYP 3A4 inducers such as phenytoin, carbamazepine,
rifampicin, barbiturates, or St John's Wort

- Pregnancy or breast-feeding

- As judged by the investigator, any evidence of severe or uncontrolled systemic
disease (eg, unstable or uncompensated respiratory, cardiac, hepatic, or renal
disease)

- Evidence of any other significant clinical disorder or laboratory finding that makes
it undesirable for the patient to participate in the study

- Other co-existing malignancies or malignancies diagnosed within the last 5 years with
the exception of basal cell carcinoma or cervical cancer in situ

- Life expectancy of less than 12 weeks