Bfore-

The purpose of this study is to investigate whether some patients with excellent responses to chronic myeloid leukaemia (CML) treatment are being overtreated, and can remain well on either a lower dose of treatment or without treatment at all.

The dose of imatinib (Glivec), nilotinib (Tasigna) or dasatinib (Sprycel) treatment will initially be cut to half the standard dose for 12 months, and then treatment will be stopped completely for a further two years. The trial information will also help to develop a de-escalation and stopping strategy for future newly diagnosed CML patients in the next British national CML study (to be known as SPIRIT3).

This study is currently recruiting (see Contacts and Locations)

Verified: September 2014

Sponsor: Avillion Development 1 Limited

Primary Outcome Measures

• TCompare proportion of participants with Major Molecular Response (MMR) at 12 Months in the bosutinib arm with that of the imatinib arm [ Time Frame: 12 Months ] [ Designated as safety issue: No ]
• MMR is defined as <0.1%Bcr-Abl1 on the International Scale (IS) by Real Time Quantitative Polymerase Chain Reaction (RT-PCR)

Secondary Outcome Measures

• Compare proportion of participants with MMR at 18 Months in the bosutinib treatment group with the imatinib treatment group [ Time Frame: 18 Months ]
• To determine the duration of MMR in the bosutinib treatment group with the imatinib treatment group [ Time Frame: 5 Years ]
• Duration of MMR is measured only for participants who initially respond to study medication.
• To determine the proportion of participants with Complete Cytogenetic Response (CCyR) by 12 Months in both treatment groups [ Time Frame: 12 Months
• CCyR is defined as absence of detectable Ph chromosomes in bone marrow aspirate
• To determine the duration of CCyR in both treatment groups [ Time Frame: 5 Years ]
• Duration of response is measured only for participants who initially respond to study medication.

Estimated Enrollment: 530

Study Start Date: June 2014

Estimated Study Completion Date: May 2020

Estimated Primary Completion Date: August 2016 (Final data collection date for primary outcome measure)

Arms Assigned

Experimental: Bosutinib
Bosutinib, 400 mg, oral administration once a day

Active Comparator: Imatinib
Imatinib, 400 mg, oral administration once a day

Detailed Description

The study will be open for enrollment until the planned number of approximately 500 Philadelphia Chromosome Positive (Ph+) patients have been randomized (approximately 250 Ph+ patients in each treatment arm; a total of approximately 530 Ph+ and Ph- patients).

All patients will be treated and/or followed for 5 years (240 weeks) after randomization until the study has closed. Patients who discontinue study therapy early due to disease progression or intolerance to study medication will continue to be followed yearly for survival for up to 5 years (240 weeks) after randomization.