Table 1 LAST Study Inclusion and Exclusion Criteria

Inclusion Criteria

 Age 18 or older

 Willing and able to give informed consent

 Diagnosed with CML in chronic phase and have either the b3a2 (e14a2) or b2a2 (e13a2) variants that give rise to the p210 BCR-ABL protein

 Currently taking imatinib, dasatinib, nilotinib or bosutinib

 Has been on TKI therapy for at least 3 years

 Documented BCR-ABL < 0.01% or undetectable BCR-ABL by RQ-PCR for at least 2 years according to the patient’s local lab

 Documented BCR-ABL < 0.01% or undetectable BCR-ABL by RQ-PCR at least 3 times prior to screening according to the patient’s local lab

 Two (2) Screening PCRs have been completed and both results are < 0.01% (better than MR4, i.e,. > 4 log reduction) by central lab

 Has been on any number of TKIs, but has not been resistant to any TKI (changes made for intolerance are allowed)

 Has been compliant with therapy per treating physician

Exclusion Criteria

 Prior hematopoietic stem cell transplantation

 Poor compliance with taking TKI

 Unable to comply with lab appointments schedule and PRO assessments

 Life expectancy less than 36 months

 Resistant to previous TKI therapy

 Pregnant or lactating women