This is a Phase III, multi-center, open-label, parallel, 2-arm, randomized study to evaluate the efficacy and safety of radotinib 300 mg Bis In Die(BID) versus imatinib 400 mg Quaque Die(QD).

This study will be conducted in Chinese patients with newly diagnosed Ph+ Chronic Myelogenous Leukemia(CML)-Chronic Phase(CP) who are previously untreated for Chronic Myelogenous Leukemia(CML).

Patients randomized to the radotinib arms will receive 300 mg of radotinib BID at approximately 12-hour intervals. Patients randomized to the imatinib 400 mg arm will receive imatinib once a day throughout the study.

The primary efficacy endpoint is the rate of Major Molecular Response(MMR) at 12 months (1 month = 4 weeks = 28 days), defined as BCR ABL1/ABL% ≤ 0.1% by international scale. The Molecular Response(MR) rate will be measured every 3 months by Real-time Quantitative(RQ)-Polymerase Chain Reaction(PCR) in a central laboratory. All patients will be treated and/or followed for 12 months (48 weeks) after randomization.

Inclusion Criteria:

1. China who are 18 years of age or older.
2. Eastern cooperative oncology group (ECOG) score 0, 1, or 2.
3. Patients with confirmed diagnosis of CML-CP within last 6 months.
4. Patients with cytogenetically confirmed Ph+ CML in chronic phase
5. Patients with typical BCR-ABL1 transcript type such as b2a2 and b3a2.
6. Patients with adequate organ function.
7. Women of childbearing potential should have negative serum or urine pregnancy test within 14 days before study entry.
8. Patients providing written informed consent before initiation of any study-related activities.

Exclusion Criteria:

1. Patients with Philadelphia chromosome negative but BCR-ABL1 positive CML.
2. Patients who had been treated with interferon or other targeted anti-cancer therapy which inhibits the growth of leukemic cells
3. Concurrently clinically significant primary malignancy
4. Patients who previously received radiotherapy
5. Patients with impaired cardiac function.
6. uncontrolled chronic medical condition