Impact of recommended weight-based dosing of granulocyte-colony stimulating factors in acute leukemia and stem cell transplant patients

Febrile neutropenia (FN) is a major risk factor for infection-related morbidity and mortality. The National Comprehensive Cancer Network recommends the prophylactic use of granulocyte-colony stimulating factors (G-CSF), dosed at 5 mcg/kg and rounded to the nearest vial size. A previous medication use evaluation conducted within a multi-hospital healthcare system demonstrated that only 67% of patients were started on appropriate weight-based dosing. The purpose of this study was to evaluate the effect of appropriate weight-based G-CSF dosing in patients on clinical outcomes. A retrospective chart review of patients with acute leukemia or stem cell transplant recipients who received G-CSF from May 2009 to September 2015 was conducted. Patient admissions were reviewed in regards to neutropenia length, incidence of FN, length of stay, and final disposition (alive or deceased). Admissions were divided into one of three weight-based dosing groups of under 5 mcg/kg, recommended 5 mcg/kg within a 10% range, and over 5 mcg/kg which were named under, recommended, and over, respectively. Ninety-four admissions were included. Average age of this patient population was 58 years old, and the majority of patients were male (53%) and Caucasian (55%). Majority of patients had been diagnosed with acute myeloid leukemia (91%). Data showed average duration of neutropenia was around 10 days regardless if the patient received under 5 mcg/kg, the recommended 5 mcg/kg or over 5 mcg/kg G-CSF (10.1 +/- 6.7 days, 8.9 +/- 9.2 days, 10.1 +/- 9.1 days, respectively). Length of stay was similar for patients regardless of initial G-CSF dose (29.6 +/- 16.0 days, 29.1 +/- 18.4 days, and 24.5 +/- 17.0, respectively). However, the incidence of FN was significantly greater for those who received under 5 mcg/kg of G-CSF (87% for under, 68% for recommended, and 54% for over). In this retrospective analysis, variations from the recommended 5 mcg/kg G-CSF dose did not significantly impact length of neutropenia, length of stay, nor mortality. However, patients who received under the 5 mcg/kg of G-CSF dose may be at a greater risk of FN.