Recombinant human granulocyte colony stimulating factor in cyclic neutropenia: use of a new 3-day-a-week regimen.

Background: G-CSF has been shown to be beneficial in cyclic neutropenia when given as a daily subcutaneous injection. We investigated the usefulness of a new three-day-a-week regimen.

Methods: A ten year old boy with cyclic neutropenia was initially treated with G-CSF 7 micrograms/kg given on alternate days for seven months. He was then placed on the same dose, given three days a week. The effectiveness of these regimens were assessed by serial CBCs and by the frequency and duration of the symptoms.

Results: The mean absolute neutrophil count (ANC) increased from 1282 before therapy to 11,718/microliters on alternate day regimen and 7716/microliters on three-day-a-week regimen. The nadir ANC improved from 30/microliters before therapy to 546/microliters and 198/microliters on treatment. The duration and frequency of mouth sores were significantly less on therapy, and there was an estimated cost savings of $23,826/year on three-day-a-week regimen compared to a daily regimen.

Conclusion: The three-day-a-week G-CSF regimen is clinically effective and cost saving in the treatment of cyclic neutropenia and should be studied in a larger cohort of patients.