White blood cell growth factor use in an outpatient oncology clinic: Lessons and opportunities learned

The increased use and high cost associated with white blood cell growth factors at our outpatient oncology clinic has prompted this evaluation. The objectives of this study were to categorize the indication for use of pegfilgrastim and filgrastim; evaluate the administration of these white blood cell growth factors; identify opportunities for cost savings; and identify ways to increase prescriber adherence to evidence-based practice guidelines. This medication use evaluation study involved retrospective data collection from patient medical records. Adult oncology patients treated in the outpatient oncology clinic who received filgrastim or pegfilgrastim were identified and included in this study. Computerized patient records were used to collect data on patient demographics, risk factors for febrile neutropenia, prescribing patterns for filgrastim and pegfilgrastim, and chemotherapy regimens. The number of pegfilgrastim and filgrastim doses were predominately used for primary prophylaxis following chemotherapy treatment. Of the 234 total doses of pegfilgrastim used in the setting of primary prophylaxis, 28 (12%), 134 (57%), and 72 (31%) doses were given to patients receiving chemotherapy regimens associated with a high risk (>20%), intermediate risk (10-20%), and low risk (<10%) of febrile neutropenia, respectively. The total number of pegfilgrastim doses used in secondary prophylaxis was 78; 20 (26%) and 58 (74%) of these doses were given to patients receiving chemotherapy regimens associated with an intermediate risk and low risk of febrile neutropenia, respectively. This study revealed a significant portion of prescribed growth factor use that was not in accordance with clinical practice guidelines.