OBJECTIVES: Within the framework of Chronic Myelogenous Leukaemia (CML) treatment in Peru, and based on a previously performed economic evaluation, we compared the costs and cost-effectiveness ratio of using 100mg/day and 140 mg/day doses of Dasatinib with the use of 800 mg/day doses of Nilotinib or an increased dose of Imatinib (800mg/day), for each phase of the disease, in patients who developed resistance to habitual doses of Imatinib METHODS: A Markov model was used for this economic evaluation, which considered a cohort of 10.000 CML patients in its three phases (chronic, accelerated and blast phase), a lifetime horizon and a 3.5 % discount rate for costs and benefits.  Model results included the costs of each treatment alternative with Dasatinib, Nilotinib or Imatinib, and Quality Adjusted Life Years (QALYs) gained.  Costs were measured in Peruvian SOLES of year 2010 RESULTS: In the chronic phase of the disease, dasatinib 100 mg/day yielded the highest amount of QALYs with 6,62 and the lowest cost-effectiveness ratio.  In the accelerated phase, Dasatinib 140 mg/day also showed the lowest cost-effectiveness compared to Nilotinib and Imatinib.  In the blast phase, dasatinib showed lower cost-effectiveness ratio than imatinib CONCLUSIONS: Dasatinib 100 mg/day showed the lowest cost-effectiveness ratios than doses of 800 mg/day of Nilotinib and imatinib 800 mg for the treatment of patients with CML resistant to usual imatinib doses in the chronic phase, as well as in the accelerated and blast phases.  Although there was an overall cost increase, especially due to the cost of Dasatinib in 140 mg/day doses, this fact was explained by the increase in life years gained and, consequently, the use of medical resources and drugs