Pegfilgrastim

Neutrophils are short-lived immune cells that are highly susceptible to cell death following myelosuppressive chemotherapy. This marked reduction in neutrophil numbers during chemotherapy increases the risk of hospitalization, infection, and infection-related mortality. It also directly impacts the clinical outcome of patients if cases of febrile neutropenia requires dose reductions or schedule delay of chemotherapy, thus reducing the clinical efficacy of chemotherapy and patient benefit from receiving appropriate treatment.

G-CSF is an endogenous haematopoietic growth factor that stimulates granulopoietic cells of the neutrophil lineage. Pegfilgrastim mimics its biological actions and binds to the same G-CSF receptor expressed on cells of myeloid lineage, such as granulocytic precursors and mature neutrophils. Upon binding of the ligand, G-CSF receptor undergoes a conformational change and activates several downstream signalling pathways including JAK/STAT, PI3K/AKT and MAPK/ERK. These pathways work to increase proliferation and differentiation of granulocyte progenitor cells, induce maturation of the progenitor cells, and enhance survival and function of mature neutrophils.