Study of Efficacy and Safety of Asciminib in Combination With Imatinib in Patients With Chronic Myeloid Leukemia in Chronic Phase (CML-CP) Who Have Been Previously Treated With Imatinib and Have Not Achieved Deep Molecular Response.

The study was a Phase 2, multi-center, open-label, randomized study of asciminib in two different doses (40 mg or 60 mg) in combination with imatinib 400 mg versus continued imatinib versus switch to nilotinib in participants with chronic myeloid leukemia in chronic phase (CML-CP) who had been previously treated with imatinib first line therapy for at least one year and had not achieved deep molecular response (DMR). Eligible participants were randomized 1:1:1:1 to receive asciminib 60 mg once daily (QD) as add-on therapy to imatinib 400 mg QD, or 40 mg QD as add-on therapy to imatinib 400 mg QD, or to continue imatinib 400 mg QD, or to switch to nilotinib 300 mg twice a day (BID). During the trial, there was no switch allowed. It was just at the moment of the randomization that the participants were selected to asciminib add-on arms or nilotinib.

Participants on the imatinib continuation arm who had not achieved MR4.5 at 48 weeks were allowed to cross-over ((CO) to receive the add-on treatment within 4 weeks after week 48 visit to receive the asciminib 60 mg combination add-on treatment, as this dose provided higher exposure. The cross-over was at the discretion of the investigator and the participant. Apart from a polymerase chain reaction (PCR) result of below MR4.5 at Week 48 visit, there were no other entry criteria for the cross-over part. Participants on nilotinib were not allowed to cross-over to receive the add-on treatment.

Participants on the study continued on the allocated treatment until treatment failure, intolerability, or for up to 96 weeks (in arms 1 to 4) after the last participant had received the first dose of treatment. After the last dose was received, every participant was followed up for safety for 30 days.