Study Purpose: This study aims to see if adding the medicine Ruxolitinib to another medicine called a Tyrosine Kinase Inhibitor (TKI) can help people with a type of blood cancer, chronic myeloid leukemia (CML), stay well without treatment for a longer time.

Study Details: People in this study have CML and have tried to stop taking their TKI medicine before but had to start again. They will take both Ruxolitinib and a TKI for 12 months. After that, they will see if they can stop taking the TKI for up to 3 years. During the first 2 years, they will have special blood tests called PCR tests. Overall, the study lasts about 4 years.

• Participation Length: Up to 4 years.
• Eligibility: Must have CML, tried stopping TKI once, and be able to follow study rules.
• Risks: Includes possible side effects from medicines and frequent blood tests.

Note: Those who have had severe CML or other serious health issues might not be eligible.