A PROSPECTIVE RANDOMIZED PHASE II STUDY EVALUATING

INTERVENTION: Trade Name: SPRYCEL Product Name: BMS‐354825‐03 Product Code: BMS‐354825‐03 Pharmaceutical Form: Tablet CONDITION: Chronic phase chronic myelogenous leukaemia (CP‐CML). INCLUSION CRITERIA: 1. Male or female patient = 18 years 2. ECOG Performance Status score 0‐2 3. Philadelphia chromosome positive newly diagnosed chronic myelogenous leukaemia (= 3 months) in chronic phase. 4. Not previously treated except with hydroxyurea 5. Signed written inform consent 6. Adequate hepatic function defined as: total bilirubin = 2.0 times the institutional ULN; ALT and AST = 2.5 times the institutional upper limit of normal (ULN). 7. Adequate renal function defined as serum creatinine = 3 times the institutional ULN. 8. Women of childbearing potential (WOCBP) must be using an adequate method of contraception Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range PRIMARY OUTCOME: Main Objective: To reduce the rate of adverse event observed in de novo CML in chronic phase patients treated with dasatinib 100 mg QD. Primary end point(s): 1. Primary endpoint : ; The cumulative rate of significant adverse events defined by all grade fluid retention, all grade pleural effusion, haematological grade 3‐4 adverse events related to dasatinib and/or all adverse event leading to dasatinib interruption within the first year of therapy.; 2. Secondary endpoints : ; a. The rate of treatment interruptions in the three arms.; b. The cumulative duration of dasatinib interruption during the first 12 months of therapy; c. The median dose of dasatinib administered during the first 12 months of therapy; d. The mean dose of dasatinib administered during the first 12 months of therapy; e. Complete cytogenetic response at 6, 12 and 18 months and every 12 months thereafter in the three arms; f. Major molecular response at 3, 6, 12 and 18 months and every 6 months thereafter defined by a standardized BCR‐ABL/ABL ratio =0.1% in the three arms; g. Complete molecular response 3, 6, 12 and 18 months and every 6 months thereafter defined by an undetectable BCR‐ABL transcript at the sensitivity level of 10‐5 in the three arms; h. Time to molecular response (major or complete); i. Relationship between peak plasmatic level (Cmax) and efficacy in the three arms; j. Relationship between through plasmatic level (Cmin) and efficacy in the three arms; k. Progression free survival at 5 years in the three arms; l. Event free survival at 5 years in the three arms; Secondary Objective: To compare the rate of treatment interruptions; To compare the cumulative duration of dasatinib interruption.; To compare the median dose of dasatinib administered during the first 12 months; To compare the mean dose of dasatinib administered during the first 12 months; To compare the cumulative rate of complete cytogenetic response at 6, 12 and 18 months and every 12 months thereafter ; To compare the cumulative rate of major molecular response at 3, 6, 12, 18 months and every 6 months thereafter. ; To compare the cumulative rate of complete molecular response at 3, 6, 12 and 18 months and every 6 months thereafter; To compare the time to molecular response (major or complete); To analyse the relationship between peak plasmatic level (Cmax) and efficacy in the three arms; To compare the progression free survival at 5 years in the three arms; To compare the event free survival at 5 years in the three arms; To compare the overall survival at 5 years in the three arms;