<qa>  What is the aim of the study?The study is controlled and randomized in Philadelphia-positive chronic myeloid leukemia Ph CML patients with complete cytogenetic response after more than one year of imatinib therapy. The aim is to explore a possible benefit in the addition of peg-interferon Peg-IFN to imatinib, in terms of the rate of achievement, molecular remission, and response duration. 