1. Patients confirmed with stage IV lung adenocarcinoma by pathologic histology or cytology who can't accept surgery and radiotherapy
2. Male or female patients aged ≥18 years, life expectancy ≥ 12 weeks
3. Eastern Cooperative Oncology Group (ECOG) performance status 0-2
4. Sensitive EGFR gene mutation(19/21)
5. Failed with first-line icotinib and have gradually progressed disease More than 6-month duration of first-line icotinib (from the first dosing to the imaging-confirmed progression; and discontinuation of icotinib is less than 14 days) No significantly increased tumor size compared with the final imaging evaluation
You may not be if
1. Any unstable systemic disease (including active infection, uncontrolled hypertension, unstable angina, congestive heart failure, myocardial infarction within the previous year, serious cardiac arrhythmia requiring medication, hepatic, renal, or metabolic disease)
2. Female subjects should not be pregnant or breast-feeding
3. Patient assessed by the investigator to be unable or unwilling to comply with the requirements of the protocol
4. Previous systemic anti-tumor therapy except for icotinib , including chemotherapy or targeted therapy ( including but not limited to monoclonal or antibodies, small molecule tyrosine kinase inhibitor, etc)
5. Tumor metastasis of the spinal cord, meninges or meningeal neoplasms confirmed by imaging or cerebrospinal fluid examination
