Flumatinib is primarily used in the treatment of chronic myeloid leukemia (CML). It functions as a tyrosine kinase inhibitor, specifically targeting the BCR-ABL fusion protein, which is a key driver in the development of CML. By inhibiting this protein, Flumatinib helps to control the proliferation of leukemia cells, thereby slowing the progression of the disease. It is often considered for patients who are resistant or intolerant to other tyrosine kinase inhibitors. The drug is administered orally, making it a convenient option for long-term management of the condition. Clinical studies have shown that Flumatinib can induce significant hematologic and cytogenetic responses in patients, improving overall survival rates and quality of life.