Imatinib is used to treat several blood cancers and related conditions:

Newly diagnosed adults and children with Philadelphia chromosome-positive chronic myeloid leukemia (Ph+ CML) in chronic phase.
Patients with Ph+ CML in blast crisis, accelerated phase, or chronic phase after interferon-alpha therapy has failed.
Adults with relapsed or refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL).
Children with newly diagnosed Ph+ ALL (in combination with chemotherapy).
Adults with myelodysplastic/myeloproliferative diseases (MDS/MPD) linked to PDGFR gene changes.
Adults with aggressive systemic mastocytosis (ASM) without the D816V c-Kit mutation or with unknown c-Kit status.
Adults with hypereosinophilic syndrome (HES) or chronic eosinophilic leukemia (CEL) with certain genetic features.

Your doctor will decide if imatinib is right for you based on your diagnosis, genetic test results, and previous treatments.