Randomized study of the combination of hydroxyurea and interferon alpha versus hydroxyurea monotherapy during the chronic phase of chronic myelogenous leukemia (CML Study II). The German CML Study Group.

: It is the long-term goal of the German CML Study Group and of the Suddeutsche Hamoblastosegruppe (SHG) to improve survival of patients with chronic myelogenous leukemia (CML). In a first randomized study (CML Study I) monotherapies with hydroxyurea or interferon alpha (IFN-alpha) were compared with a standard busulfan regimen with regard to duration of the chronic phase and survival. The main results of this study were published, 1-3 and a long-term follow up is planned. In a second randomized study the effect of the combination of IFN-alpha and hydroxyurea versus hydroxyurea monotherapy on survival is being investigated. This paper provides a first preliminary report on the study concept, patient recruitment, state of documentation and initial patients' characteristics 9 months after closure of the study.