Combination of granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (EPO) for the treatment of advanced non-responsive chronic lymphocytic leukemia

We report the use of a colony-stimulating granulocyte-macrophage factor (GM /CSF) and erythropoietin (EPO) combination as salvage treatment in four hea vily-pretreated patients with refractory/recurrent B-CLL. Induction therapy was subcutaneous GM-CSF 2.5 mu g/kg, and EPO, 150 units/kg both daily for the first 14 d. Maintenance therapy was GM-CSF on days 1, 3 and 5 and Epo o n days 2, 4 and 6 at the same doses with weekly recycling. All the patients responded favourably. A significant reduction of lymphocytosis, lymphoaden omegaly, and organomegaly was obtained within one month of therapy. The num ber of infections and transfusional requirement decreased dramatically. The hemoglobin increased to over 11 g/dl in 3 out of 4 patients. With a median follow-up of 11 months (range 5-13) we observed 4 partial responses (NCI/I WCLL) and only one progression after a 10-month partial response. This combination regimen seems very active, safe and easy to administer. It may represent a promising therapeutical option in heavily pretreated patie nts. Further clinical and biological studies on a larger cohort of patients are needed to confirm these preliminary data, to clarify the hypothetical interactions between these cytokines and B-CLL cell proliferation pathways, and to establish if this therapy may have an impact on survival.