1.2 BENEFIT-RISK ASSESSMENT In every clinical trial, anticipated benefits need to be weighed against the study associated risks. In previous investigations where G-CSF has been used, no G-CSF associated adverse reactions were reported. Only the MAGIC trial was prematurely stopped due to possible safety concerns in treated patients in terms of an unexpectedly high restenosis rate in stented vessels [17]. However, only three patients in the G-CSF group received angiographic follow-up, thus no clear conclusion about the incidence of restenosis should have reasonably be drawn from this study. In all other studies using G-CSF adverse events were comparable between patients and controls [13]. Nevertheless G-CSF is largely used in oncology for treatment of febrile neutropenia and in hematology for this indication and for mobilization of stem cells for transplantation. As this regard G-CSF is considered reasonably safe without any association with a documented increase in malignancies [18].