A 40 year old male patient is hospitalised with huge splenomegaly, marked sternal tenderness, and a total leucocyte count of 85,000 per cubic millimetre with large percentage of myelocytes and meta myelocytes, which one of the following drugs is best indicated for his disease ?

Chronic phase of CML begins as a proliferative disorder & consists of excessive proliferation of myeloid cells of intermediate grade(myelocytes & metamyelocytes) & mature segmented neutrophils.Drugs used in chronic phase of CML include imatinib,dasatinib, nilotinib, or classical cytotoxic drugs such as hydroxycarbamide(hydroxyurea) or interferon. Reference:Davidson's principles & practice of medicine 22nd edition pg no 1039.