This is a phase Ib, multi-center, open label study evaluating the safety and efficacy of CT053PTSA in combination with gefitinib in patients with EGFR mutation, T790M negative NSCLC who have progressed after EGFR TKI treatment.

This study is being carried out in two parts, part 1 and part 2.

Part 1: This is the dose-escalation part. The primary purpose of the part 1 portion is to determine the dose limiting toxicity (DLT) and maximum tolerated dose (MTD), and recommend the appropriate doses of CT053PTSA in combination with gefitinib for further studies.

Part 2: This is the expansion part. The part 2 portion of this study will continue to evaluate the safety and efficacy of the combination of CT053PTSA and gefitinib , at the appropriate doses recommended in Part 1, in patients with EGFR mutation, T790M negative NSCLC.

Inclusion Criteria:

• Histologically or cytologically confirmed Stage IIIB or IV NSCLC
• Resistance to EGFR TKI (1st, 2nd or 3rd generation)
• Histological or cytological evidence of EGFR mutation and T790M negative after progression on last EGFR TKI therapy
• c-Met GCN ≥ 6 or cluster amplification is required if participant is resistant to1st or 2nd generation EGFR-TKI ;c-MET GCN statue is not required, If participant is resistant to3rd generation EGFR-TKI （osimertinib）；
• Measurable disease according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1)
• Toxicity recovered to NCI CTCAE v.4.03 Grade ≤1 from previous treatments (except alopecia)
• ECOG performance status (PS) 0 or 1
• Life expectancy of ≥ 12 weeks
• Adequate organ function

Exclusion Criteria:

• Prior treatments

  • Chemotherapy, targeted therapy (except EGFR TKI), immunotherapy, radiotherapy, or major surgery within 4 weeks prior to study treatment
  • Nitrosourea and mitomycin chemotherapy within 6 weeks prior to study treatment
  • EGFR TKI treatment within 2 weeks prior to study treatment
  • Had received live vaccine within 4 weeks prior to study treatment
  • Had received any investigational agent from other clinical study within 4 weeks prior to study treatment or are currently participating in other clinical trials
  • Previous treatment with any other c-MET inhibitor or Axl inhibitor (eg, crizotinib, cabozantinib, volitinib, INC280)

• Symptomatic, untreated or unstable central nervous system metastases

• Spinal cord compression, carcinomatous meningitis or leptomeningeal diseaseonly (patient are only permitted if treated, asymptomatic and stable for at least 4 weeks prior to start of study treatment)

• Interstitial pneumonia or radiation pneumonitis

• Uncontrolled hypertension that require more than two anti-hypertensive agents to control, or systolic blood pressure (BP) >140mmHg or diastolic BP >90 mmHg before the first administration (BP is the mean blood pressure of two measures that 1 hours interval or above)

• Doppler ultrasound evaluation：Left ventricular ejection fraction < 50%

• Grade ≥ 2 of arrhythmia (assessed by NCI CTCAE 4.03), or symptomatic bradycardia, or male with QTCF > 450 ms or female with QTCF > 470 ms, or patients with a history of torsion or congenital QT prolonged syndrome long QT syndrome

• Certain factors that would preclude adequate absorption of CT053PTSA and gefitinib (eg. unable to swallow, chronic diarrhea, intestinal obstruction)

• Significant hemoptysis within 2 months prior to enrollment, or a daily hemoptysis volume is 2.5 ml or above

• Patients with evidence of bleeding tendency, including the following cases: gastrointestinal bleeding, hemorrhagic gastric ulcer, fecal occult blood ++ and above; or melena or hematemesis within 2 months; or visceral bleeding that may occur considered by investigator

• History of immunodeficiency, or other acquired or congenital immunodeficiency, or history of organ transplantation

• Any disease of the following bellowed within 12 months prior to administration: Myocardial infarction, severe angina, or unstable angina, coronary or peripheral artery bypass graft, congestive heart failure, or cerebrovascular events (including transient ischemic attack)

• Pulmonary embolism within 6 months prior to administration

• Active infection of hepatitis B, or infection of HIV

• Other malignancies within 5 years prior to enrollment, with the exception of carcinoma in situ of the cervix, basal or squamous cell skin cancer

• History of thyroid dysfunction, and the thyroid function cannot be maintained at the normal range with drugs.

• Serious electrolyte imbalance in the investigator's judgment

• Pregnant or lactating woman

• Any other reason the investigator considers the patient is not suitable to participate in the study