A Study on the Withdrawal of Second-generation Tyrosine Kinase Inhibitors After Dose Reduction in Patients With CML

This Study is a Multicenter, Single-arm, Prospective Study to Evaluate the Efficacy and Safety of Drug Discontinuation After Dose Reduction in Ph+CML-CP Patients Threated With 2G-TKI.

patients with Ph+ CML-CP who have been treated with second-generation TKIs (nilotinib, dasatinib) for at least 3 years and maintains MMR for at least 2 years, continue to be treated with halved dose for 12 months, and then stop for 12 months.

1.Patients with Ph+ CML-CP who have been treated with second-generation TKIs (nilotinib, dasatinib) for at least 3 years and maintains MMR for at least 2 years.

2。During the TKI reduction phase, the peripheral blood BCR/ABLIS was detected by Q-PCR every two months and continuously monitored for 12 months. In the TFR period, the peripheral blood BCR/ABLIS was detected once a month for the first 6 months; the peripheral blood BCR/ABLIS was detected once every two months for the next 6 months; after that, the peripheral blood BCR/ABLIS was detected once every three months.

3.If the patients detected molecular recurrence (loss of MMR, BCR/ABL IS>0.1%),the original dose of 2G-TKI should be administered

Inclusion Criteria:

1. Male or female over 18 years
2. Patients diagnosed as Ph+ (or Ph- but PCR-positive for BCR-ABL) CML-CP
3. Patients have received one of the second-generation TKIs (nilotinib, dasatinib) for at least 3 years
4. Patients have maintained MMR (BCR/ABL IS<0.1% or more) at least 2 years
5. in the past 24 months, at least three times recent molecular reactions have confirmed MMR
6. Patients have signed the informed consent

Exclusion Criteria:

1. patients with the presence or history of T315I mutation
2. patients with the presence of rare unquantifiable atypical transcripts
3. Patients with comorbid cardiovascular disease or a history of severe cardiovascular disease
4. patients have history of accelerated or blast phase, or suspected blast disease
5. patients have received allogeneic hematopoietic stem cell transplantation
6. patients have severe abnormal liver and kidney function (ALT > upper limit of normal, AST > 3 times normal upper line, glomerular filtration rate < 50%)
7. patients combined with other tumors or a history of other malignancies ECOG score>3
8. Two-line abnormality in the patient's blood routine examination
9. women is pregnant or nursing