Once-per-cycle pegfilgrastim versus daily filgrastim in pediatric patients with Ewing sarcoma.

The use of the recombinant human granulocyte colony-stimulating factor filgrastim to shorten the duration of severe neutropenia after cytotoxic chemotherapy has become an integral part of supportive care. However, due to its short serum half-life, filgrastim must be injected daily. Pegfilgrastim, a new long-lasting form of filgrastim administrated once per cycle, has been shown in adults to be as effective in reducing the duration of severe neutropenia as daily filgrastim. The aim of this study was to evaluate the effects of pegfilgrastim in pediatric patients. Five children with Ewing sarcoma were alternately treated with a single 100 microg/kg pegfilgrastim dose or daily doses of 10 microg/kg Filgrastim after a total number of 58 chemotherapy cycles. Pegfilgrastim was well tolerated. The duration of severe neutropenia and the incidence of febrile neutropenia after pegfilgrastim and filgrastim were comparable. By using pegfilgrastim, the number of subcutaneous injections could be reduced to one single injection per cycle.