The objective of this Phase II study is to assess the potential of asciminib in managing CML-CP or CML-AP in patient carrying the T315I mutation. The presence of this mutation introduces treatment difficulties due to the limited available options. The study seeks to collect additional data on the effectiveness and safety of asciminib for these patients. By determining the drug's capacity to manage the disease and enhance patients outcomes, the study is designed to fill the unmet medical need and potentially offer a new therapeutic path for patients at a treatment deadlock.