BACKGROUND:  Achieving complete cytogenetic response (CCyR) is associated with superior progression-free survival in patients with CML [1].  How this endpoint affects cost has not been evaluated.   OBJECTIVES: To assess the cost needed to achieve one CCyR with dasatinib 140 mg vs. imatinib 600 and 800 mg in imatinib-resistant CP-CML, from the perspective of national health insurance in the Czech Republic, Hungary and Romania.METHODS: An economic analysis was conducted using the number of patients needed to be treated (NNT) to achieve one CCyR.  The incremental cost for achieving CCyR in 15 months was determined. CCyR rates for dasatinib 140 and imatinib 800 mg were based on a randomized phase 2 trial START-R [2].  Given no published data on imatinib 600mg, its CCyR rate was assumed to be the same as for imatinib 800 mg; an assumption in favor of imatinib.  Costs were based on reimbursed drug-prices from national lists. In Hungary, reimbursed amounts for 600 or 800 mg of imatinib are the same.RESULTS: To achieve one CCyR, NNT is 6,25 for imatinib and 2,5 for dasatinib. The costs to achieve one CCyR during 15 months of therapy are CZK9,1 million (€363,172), HUF52.8 million (€218,492) and RON1.2 million (€334,146) lower for dasatinib compared to imatinib 800 mg. The economic advantage of dasatinib remains when compared to imatinib 600 mg. The incremental costs to achieve one CCyR between imatininb 600 mg and dasatinib are CZK5.7 million (€228,664), HUF52,8 million (€218,492) and RON0.7 million (€205,316).CONCLUSIONS: In imatinib-resistant CP-CML patients, therapy with dasatinib provides better efficacy and lower cost compared to imatinib 600 and 800 mg in Central and Eastern Europe to achieve one CCyR. The magnitude of the advantage varies due to different pricing and financing systems. [1] Hughes et al. NEJM 2003;349:1423-32; [2] Kantarjian et al. Blood 2007;109:5143-50.