Therapeutic administration of pegfilgrastim instead of prophylactic use

Pegfilgrastim is a new growth factor which can be administered subcutaneously once (versus multiple doses for days) on the day neutropenia occurs after chemotherapy. Our aims were to determine: (a) the percentage of patients who needed growth factor (pegfilgrastim) supportive treatment, (b) the duration of neutropenia-leukopenia after pegfilgrastim administration, and (c) the safety in using pegfilgrastim as a treatment and not as a prophylactic agent.

Ninety-eight patients were evaluated. All patients were scheduled to undergo chemotherapy treatment, which was either first- or second-line, and some patients had previously received granulocyte colony-stimulating growth factor (G-CSF): filgrastim on a daily basis. Twenty-five/98 patients required G-CSF support and were treated with pegfilgrastim 6 mg; the first 12 patients were admitted to hospital and remained until recovery from grade 3-4 neutropenia; the other 13 patients were treated on an outpatient basis or at home. Pegfilgrastim was administered when neutropenia appeared (days 6-8 following chemotherapy treatment).

Therapeutic administration of pegfilgrastim on the day serious neutropenia occurred was needed by 25/98 patients (25.51%). White blood cell recovery for both grade 3-4 neutropenia was observed within 1-3 days in 75% of the patients treated with pegfilgrastim and in the remaining 25%, within 5 days.

Pegfilgrastim, an active hemopoietic growth factor with effective slow-absorption properties, can be used safely, not necessarily as a prophylactic agent but on an outpatient basis as a therapy for serious neutropenia.