Study Design and Methods: Forty consecutive normal subjects who received filgrastim (6 mu g/kg) subcutaneously twice daily for 4 to 6 days in preparation for apheresis were monitored prospectively by clinical and laboratory evaluation.

Results: Sixty-two percent of the subjects required oral analgesics. None discontinued filgrastim prematurely. Bone pain (82%), headache (70%), fatigue (20%), and nausea (10%) were reported. Filgrastim caused a mean eightfold increase in neutrophil counts, a mean twofold increase in lymphocyte counts, a mean twofold rise in alkaline phosphatase and lactate dehydrogenase levels, and minor changes in serum potassium, magnesium, and uric acid. Adverse events and laboratory effects resolved within 7 days after apheresis. No apheresis stem cell donor required transfusion or hospitalization, and only one required an additional clinic visit after completion of apheresis. By comparison, a retrospective analysis of 33 normal marrow donors demonstrated that all received transfusion(s), 3 were hospitalized, and 3 required additional clinic visits after the marrow harvest. The median total charges related to the two procedures were comparable (p = 0.43), although the charges were significantly lower for donors requiring only one apheresis procedure (p = 0.002).

Conclusion: Filgrastim mobilization and apheresis of blood stem cells constitute a safe, well-tolerated, and comparable or less expensive alternative to the traditional marrow harvest.