PRIMARY OBJECTIVES:
I. To determine the 2-year treatment free remission (TFR) rate of children, adolescents,
and young adults with chronic myeloid leukemia - chronic phase (CML-CP) following
discontinuation tyrosine kinase inhibitor (TKI).
II. To estimate the re-induction rate and maintenance of molecular remission (BCR-ABL1 =<
0.1%) at 1 year after restarting TKI for children, adolescents, and young adults.
SECONDARY OBJECTIVE:
I. To describe clinical factors and laboratory correlates affecting the persistence of
major molecular remission (MMR) and re-initiation of treatment after stopping TKI (e.g.
patient demographics, duration and level of prior molecular remission, duration and type
of TKI, clinical presentation at diagnosis and immune studies).
EXPLORATORY OBJECTIVES:
I. To describe change in height standard deviation score over time in patients who are
able to discontinue their TKI.
II. To describe the long-term health outcomes including but not limited to gonadal
function, endocrine function, and bone metabolism in patients who are able to discontinue
TKI as well as those that need to restart TKIs.
III. To describe differences in patient-reported health status after stopping TKIs,
including those who need to resume TKI after stopping.
IV. To describe the incidence and characteristics of TKI withdrawal syndrome in children.
V. To evaluate changes in neurocognitive outcomes of patients enrolled on this study
using a patient-completed, performance-based, computerized measure of neuropsychological
functioning and a parent-report/self-report questionnaire.
OUTLINE:
Patients stop taking TKI medication within 10 days after enrollment. Patients undergo
peripheral blood collection to monitor loss of MMR every 4 weeks in year 1, every 6 weeks
in year 2, and every 12 weeks in year 3. Patients who lose their molecular remission may
restart TKI medication and are monitored every 4 weeks in year 1, every 6 weeks in year
2, and every 12 weeks in year 3.
After completion of study treatment, patients are followed up annually.