Inclusion Criteria:

          -  Histologically confirmed nonsquamous NSCLC with activating EGFR mutation (on exon 19
             deletion or exon 21 L858R mutation)

          -  Stage IIIb, IV or recurrent NSCLC (AJCC 7th criteria)

          -  Age ≥ 20 years

          -  ECOG performance status of 0 or 1

          -  At least one measurable lesion by RECIST 1.1

          -  Progression after first line treatment with EGFR TKIs for advanced NSCLC

          -  Asymptomatic brain metastasis or symptomatic brain metastasis treated with local
             treatment such as operation, whole brain radiotherapy, or gamma-knife surgery

          -  At least 2 weeks later after whole brain radiotherapy or palliative radiotherapy

          -  Adequate renal function: estimated creatinine clearance ≥ 45 mL/min

          -  Organ function as evidenced by the following; Absolute neutrophil count > 1.5 x 109/L;
             platelets > 100 x 109/L; total bilirubin ≤1.5 UNL; AST and/or ALT < 3 UNL, in case of
             known hepatic metastasis, AST/ALT< 5 UNL

          -  Written informed consent form

          -  No other previous systemic chemotherapy

        Exclusion Criteria:

          -  Uncontrolled systemic illness such as DM, CHF, unstable angina, hypertension or
             arrhythmia

          -  Patients with post-obstructive pneumonia or uncontrolled serious infection

          -  Pregnant or nursing women (Women of reproductive potential have to agree to use an
             effective contraceptive method)

          -  Uncontrolled symptomatic brain metastasis

          -  Presence of third space fluid which cannot be controlled by drainage

          -  Prior history of malignancy within 5 years from study entry except for adequately
             treated basal cell or squamous cell skin cancer or in situ cervical cancer,
             well-treated thyroid cancer.