Study of Efficacy of CML-CP Patients Treated With ABL001 Versus Bosutinib, Previously Treated With 2 or More TKIs

The purpose of this pivotal study was to compare the efficacy of asciminib (ABL001) with that of bosutinib in the treatment of patients with CML-CP having previously been treated with a minimum of two prior ATP-binding site TKIs. Patients intolerant to the most recent TKI therapy must have had BCR-ABL1 ratio \> 0.1% IS at screening and patients failing their most recent TKI therapy must have met the definition of treatment failure as per the 2013 European LeukemiaNet (ELN) recommendations. Patients with documented treatment failure as per 2013 ELN recommendations while on bosutinib treatment had the option to switch to asciminib treatment within 96 weeks after the last patient has been randomized on study.

Patients were randomized in a 2:1 ratio to asciminib 40 mg BID or bosutinib 500 mg QD. Randomization was stratified by major cytogenetic response (MCyR) at screening. Patients with documented treatment failure (specifically meeting lack of efficacy criteria adapted from the 2013 ELN recommendations) while on bosutinib treatment were offered the option to switch to asciminib treatment within 96 weeks after the last patient was randomized to the study.