title: Risk of chemotherapy-induced febrile neutropenia in cancer patients receiving pegfilgrastim prophylaxis: does timing of administration matter?
abstract: OBJECTIVE
  Contrary to the approved indication for pegfilgrastim prophylaxis, some patients receive it on the same day as the last administration of chemotherapy in clinical practice, which could adversely impact risk of febrile neutropenia (FN). An evaluation of the timing of pegfilgrastim prophylaxis and FN risk was undertaken.
  
  
  METHODS
  A retrospective cohort design and data from two US private health care claims repositories were employed. Study population comprised adults who received intermediate/high-risk chemotherapy regimens for solid tumors or non-Hodgkin's lymphoma (NHL) and received pegfilgrastim prophylaxis in ≥1 cycle; all cycles with pegfilgrastim were pooled for analyses. Odds ratios (OR) for FN during the cycle were estimated for patients who received pegfilgrastim on the same day (day 1) as the last administration of chemotherapy versus days 2-4 from chemotherapy completion.
  
  
  RESULTS
  The study population included 45,592 patients who received pegfilgrastim in 179,152 cycles (n = 37,095 in cycle 1); in 12 % of cycles, patients received pegfilgrastim on the same day as chemotherapy. Odds of FN were higher for patients receiving pegfilgrastim prophylaxis on the same day as chemotherapy versus days 2-4 from chemotherapy in cycle 1 (OR = 1.6, 95 % CI = 1.3-1.9, p < 0.001) and all cycles (OR = 1.5, 95 % CI = 1.3-1.6, p < 0.001).
  
  
  CONCLUSIONS
  In this large-scale evaluation of adults who received intermediate/high-risk regimens for solid tumors or NHL in US clinical practice, FN incidence was found to be significantly higher among those who received pegfilgrastim prophylaxis on the same day as chemotherapy completion versus days 2-4 from chemotherapy completion, underscoring the importance of adhering to the indicated administration schedule.
authors.affiliation: Policy Analysis Inc. (PAI), Four Davis Court, Brookline, MA, 02445, USA. dweycker@pai2.com.
authors.forename: Derek
authors.initials: D
authors.lastname: Weycker
authors.affiliation: Amgen Inc, Thousand Oaks, CA, USA.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Li
authors.affiliation: Policy Analysis Inc. (PAI), Four Davis Court, Brookline, MA, 02445, USA.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Figueredo
authors.affiliation: Amgen Inc, Thousand Oaks, CA, USA.
authors.forename: Rich
authors.initials: R
authors.lastname: Barron
authors.affiliation: Amgen Inc, Thousand Oaks, CA, USA.
authors.forename: Spiros
authors.initials: S
authors.lastname: Tzivelekis
authors.affiliation: Policy Analysis Inc. (PAI), Four Davis Court, Brookline, MA, 02445, USA.
authors.forename: May
authors.initials: M
authors.lastname: Hagiwara
mesh_terms: D064146:Chemotherapy-Induced Febrile Neutropenia / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage / Q000009:adverse effects / Q000378:metabolism* / Q000627:therapeutic use; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000209:etiology; D011092:Polyethylene Glycols; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D012189:Retrospective Studies
chemical_list: D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; C455861:pegfilgrastim; D011092:Polyethylene Glycols; D000069585:Filgrastim
keywords: Febrile neutropenia; Granulocyte colony-stimulating factor; Neulasta; Pegfilgrastim