Castagna, L., Bramanti, S., Levis, A., Michieli, M. G., Anastasia, A., Mazza, R., . . . Santoro, A. (2010). Pegfilgrastim versus filgrastim after high-dose chemotherapy and autologous peripheral blood stem cell support. Annals of Oncology, 21, 1482–1485.

 

To demonstrate that one single fixed dose of pegfilgrastim (PEG) was not inferior compared to daily doses of filgrastim after high-dose chemotherapy (HDC) and autologous peripheral stem cell transplant.

Comparisons between two different granulocyte colony-stimulating factors (G-CSFs) (i.e., PEG and filgrastim) were highlighted in this article. The researcher wanted to reveal that PEG is the same high quality as filgrastim after receiving HDC and peripheral blood stem cells starting from day 1. A single fixed dose of PEG was given 24 hours after stem cell infusion.  In the control arm, 5 mcg/kg/day of filgrastim was given from day 1 until absolute neutrophil count (ANC) recovered to greater than .5x 10⁹/l.  Each setting followed its own supportive care and prophylaxis guidelines; however, all patients received quinolone prophylaxis.

• Seventy-seven of 80 patients were enrolled (three were excluded).
• Patients included were older than 18 years.     
• Fifty-six percent of patients were male and 44% were female. 
• Key disease characteristics were multiple myeloma, non-Hodgkin lymphoma, Hodgkin lymphoma, acute leukemia, and solid tumors.
• Other key sample characteristics were duration of severe neutropenia, ANC recovery days, febrile days, requirement of antibiotics, disease status, and conditioning regimen.

• Multi-site (three)  
• Inpatient and outpatient 
• The locations were not specified.

• Patients were undergoing the active treatment phase of care.
• The study has clinical applicability for late effects and survivorship. 

This was an open-label, randomized study with a noninferiority design.

• Duration of severe neutropenia (ANC <.5x10⁹/l)
• Number of days to achieve ANC greater tha 1.0x10⁹/l
• Number of days with fever greater than 38°C
• Duration of antibiotic and antimycotic therapy
• Number of documented infections
   

This study illustrated that the use of a single fixed dose of PEG was not inferior to the use of daily filgrastim. There were no significant differences in measured outcomes between the two groups and no differences in treatment side effects.

PEG can be use alternately to filgrastim as it is only given as one single fixed dose of 6 mg as compared to daily doses of filgrastim.  Infection-related outcomes studied were not different between these two treatment approaches.

• Small sample (<100)
• No blinding, with risk of bias. 
• Other prophylactic treatments varied at different study settings, so care to prevent infections was not consistent for all patients in the study.

Use of a single dose of PEG rather than daily injections of filgrastim may be a useful alternative for these types of patients in order to avoid multiple injections.  Findings of this study were limited by sample size, study design issues, and the fact that other prophylactic treatment was not consistent throughout the sample.  Further research in this area will be helpful to confirm differences in the relative equivalency of these two approaches.