Imatinib Discontinuation in Patients With Chronic Myeloid Leukemia Chronic Phase With Sustained MR4log

Study Overview
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Brief Summary
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This study will evaluate the proportion of subjects with chronic myeloid leukemia chronic phase that sustain major molecular response after imatinib discontinuation. To be eligible for this protocol, the subject must have received imatinib as first line regiment for at least 3 years with sustained molecular response of 4log (RM4log) or higher for one year.

Detailed Description
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Patients will be followed for 2 years, with molecular monitoring, every month in the first year and then every 2 months. Imatinib will be restarted if the major molecular response (RM3log) is lost during the study or if the subject withdraw the informed consenting. The primary objective is to measure the number of subject that sustain the major molecular response (RM3log or BCR-ABL level below 0.1%) after 2 years of follow-up. BCR: breakpoint cluster region ABL: abelson murine leukemia RM3log: major molecular response, BCR-ABL level below 0.1% (IS)

Official Title
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Imatinib Discontinuation in Patients With Chronic Myeloid Leukemia Chronic Phase With Sustained MR4log

Conditions
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Leukemia, Myeloid, Chronic-Phase

Intervention / Treatment
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* Other: imatinib discontinuation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chronic myeloid leukemia chronic-phase, defined by the World Health Organization criteria Treatment with imatinib for at least 36 months BCR-ABL levels below 0,01% (IS) or MR4log in the last 12 months Exclusion Criteria: Previous allogeneic stem cell transplantation Previous treatment with dasatinib, nilotinib, bosutinib or ponatinib Imatinib dose escalation at any time, due to loss or inadequate response BCR-ABL mutation IS: International Scale MR4log: molecular response of 4log or <0,1% (IS)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: single-arm study; all patients will discontinue imatinib (intervention)
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Discontinuation<br>All subjects will discontinue imatinib | Other: imatinib discontinuation<br>* imatinib discontinuation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of subjects that remain with RM3log after imatinib discontinuation | Number of subjects that sustain BCR-ABL level below 0,1% after 24 months of follow up. | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of subjects that recover MR3log after imatinib reintroduction | In the population that do not sustain BCR-ABL below 0,1% during the study, the time to recover the response after imatinib reintroduction will be measured | 6 months | 
| Analysis of immunological profile of all subjects | Study of lymphocytes population by flow cytometry, including NK and T population | 24 months | 
| Safety and tolerability of imatinib discontinuation | Number of participants with treatment-related adverse events as assessed by CTCAE v4.0 | 24 months |