Use of a G-CSF in this setting was investigational in that it was administered to patients contrary to current treatment guidelines (Crawford et al. 2010, 2013; Smith et al. 2006; Aapro et al. 2011), yet treatment with lipegfilgrastim was consistently more effective than placebo in reducing the duration and incidence of severe neutropenia and time to ANC recovery, with an acceptable safety and tolerability profile in this patient population. This evidence concerns the gene CSF3 and neutropenia.