Long-term Safety of Asciminib in Patients With Philadelphia Chromosome-Positive CML or ALL Continuing From Parent Studies

The primary objective is to assess long-term safety of asciminib in participants with chronic myelogenous leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia who roll over from parent studies, with particular evaluation of serious adverse events and adverse events. This is clinically relevant for characterizing extended treatment tolerability during continued exposure. The secondary objective is to evaluate clinical benefit as assessed by the investigator.

The trial population included 201 participants with chronic myelogenous leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia. Both female and male participants were represented, and the age range included pediatric and adult patients. The population was selected from participants currently receiving asciminib or study treatment received in the comparator arm while enrolled in a Novartis-sponsored study, and who had completed the treatment phase and were considered by the investigator to benefit from continued treatment. Relevant lifestyle considerations were not provided. The sponsor did not provide additional information on general health status or further inclusion or exclusion criteria.

This is an open-label, multi-center rollover study in participants with chronic myelogenous leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia who have completed a Novartis-sponsored parent study and are considered by the investigator to benefit from continued treatment. The study is designed to assess long-term safety during continued treatment with asciminib, including the frequency and severity of adverse events and serious adverse events, while providing ongoing access to study treatment. The overall trial duration is estimated from 30 August 2022 to 30 August 2030. Participant involvement begins with a screening visit to confirm eligibility and review completion of the parent protocol, followed by scheduled study visits for safety assessment and evaluation of clinical benefit, and ends with an end-of-study visit. The expected duration of individual participation is not specified. Early termination may occur if the participant no longer meets the study requirements, if treatment is completed or discontinued, or if the investigator determines that continued participation is no longer appropriate.

The investigational treatment was asciminib hydrochloride, administered by oral use at a dose of 560 mg. The study was an open-label rollover design intended to provide continued access to asciminib for participants who had completed a parent study and were considered by the investigator to benefit from ongoing treatment. Long-term safety was assessed through monitoring of serious adverse events and adverse events.

Non-experimental treatment options included nilotinib, dasatinib, imatinib, and bosutinib, each administered by oral use. Nilotinib was given as Tasigna 150 mg hard capsules or Tasigna 200 mg hard capsules at a dose of 600 mg. Dasatinib was administered at a dose of 100 mg. Imatinib was administered at a dose of 400 mg. Bosutinib was administered at a dose of 500 mg. The study description does not specify any placebo or additional comparator treatment.

Administration details beyond route, dose, and oral formulation were not specified. Participant compliance monitoring was not described in the source data.

Efficacy will be assessed by the proportion of participants with clinical benefit as assessed by the investigator at scheduled visits.