Pegylated interferons have been associated with a greater decrease in absolute neutrophil counts than standard interferons, requiring dose reduction secondary to neutropenia in 18-20% of treated patients. While neutropeniais common, rarely is the neutropenia severeenough to warrant permanent discontinuationof therapy. If the neutrophil count drops below0.75 x 109 / L, the pegylated interferon doseshould be reduced by 50%. If the neutrophilcount falls below 0.50 x 109 / L, therapy shouldbe discontinued. Neutrophil counts usuallyreturn to pretreatment levels within four weeksof stopping therapy. Based upon the concern ofneutropenia, many physicians have advocatedthe use of granulocyte-colony stimulating factor(G-CSF) at a dose of up to 300 ug subcutaneouslyper week. Currently, there are no clinical trials to demonstrate the effectiveness of G-CSF although clinical experience does support its efficacy in certain situations. Guidelines state: “Routine use of growth factors, such as epoetin and granulocyte colony-stimulating factor (G-CSF) was considered but not recommended”. At this time there is an absence of data supporting the preemptive use of growth factors in this patient population.
NY State Gudielines for Hep. C. - http://www.health.state.ny.us/diseases/communicable/hepatitis/guidelines/appena.htm
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