CSF3 and neutropenia: Filgrastim (Neupogen® from Amgen) and the sustained release version pegfilgastrim or Peg-G-CSF (Neulasta® from Amgen) are made of recombinant granulocyte colony stimulating factor (G-CSF) which successfully reduced neutropenia from SPE-like proton irradiation in a mouse-model [152].