To assess efficacy and safety of oral X-396 (Ensartinib) capsule in Chinese ALK-positive NSCLC patients with brain metastases, eligible patients will be enrolled with objective responses being primary outcome measures.

In this phase Ⅱ, open-label, single arm, multicenter study, efficacy and safety of oral X-396 capsule (Ensartinib) in 37 Chinese ALK-positive NSCLC patients with brain metastases will be assessed. Eligible patients will receive 225mg X-396 capsules once daily and objective responses of brain metastasis based on investigator assessment according to Response Assessment in Neuro-Oncology (RANO) are primary outcome measures.

Inclusion Criteria:

1. Female or male, 18 years of age or older
2. Histologically or cytologically confirmed locally advance or recurrent/metastatic NSCLC that was positive for ALK mutations.
3. Contrast-enhanced MRI or CT confirmed parenchymal brain metastases with at least one measurable lesion (according to RANO and RECIST 1.1), which was not previously treated with radiotherapy.
4. At most once treated with chemotherapy, which must have been completed at least 4 weeks before the initiation of study treatment. Any adverse events related to previous chemotherapy treatment have disappeared.
5. A Karnofsky Performance Status score of at least 60.
6. An expected survival time of at least 12 weeks.
7. Adequate organ functions.
8. Drug related toxicities has been relieved to grade 1 (based on NCI CTCAE v4.03), except for hair loss.
9. Being willing and able to comply with scheduled visits, treatment plans, laboratory tests and other study procedures.
10. Signed and dated informed consent.

Exclusion Criteria:

1. Currently under treatment of other systemic anti-cancer therapies.
2. Evidence of active malignancy within last 5 years.
3. Patients who participated in other clinical trials within last 4 weeks before the initiation of study treatment.
4. Patients who received surgery or immunotherapy within last 4 weeks before the initiation of study treatment.
5. Patients who need to receive drugs which are potent CYP3A4 inhibitors or inducers within last 2 weeks before the initiation of study treatment and during the study.
6. Patients who previously received organ transplantation or stem cell transplantation.
7. Patients with clinically significant cardiovascular diseases.
8. Patients with active gastrointestinal diseases or other conditions that will interfere significantly with the absorption, distribution, metabolism or excretion of study medication.
9. Patients with interstitial lung disease history or signs of active interstitial lung disease.
10. Patients with known allergy or delayed hypersensitivity reaction to study drug or its excipients.
11. Pregnant and lactating women.
12. Patients with other illness or medical conditions potentially interfering with the study treatment.