Abstract
To define the maximum tolerated dose and to study whether recombinant human interleukin-3 (rhIL-3) reduced chemotherapy-induced neutropenia and thrombocytopenia, 20 chemotherapy-naive patients with advanced ovarian cancer eligible for treatment with 6 cycles of carboplatin- cyclophosphamide every 4 weeks (day 1) were entered in a phase I/II open, single-center trial. Cohorts of five patients received during 7 days 1, 5, 10, or 15 micrograms/kg/d rhIL-3 (days 5 through 11) in cycles 1, 3, and 5 by continuous intravenous (IV) infusion or once daily subcutaneous (SC) administration. In control cycles 2, 4, and 6, no rhIL-3 was administered. rhIL-3 significantly increased the recovery of leukocyte, neutrophil, and platelet counts, especially at 5, 10, and 15 micrograms/kg rhIL-3. rhIL-3 also increased basophil, eosinophil, monocyte, and lymphocyte counts at this dose steps. Effects on reticulocytes were limited. No difference in efficacy between SC and IV rhIL-3 treatment was found. Chemotherapy postponement for insufficient bone marrow recovery was necessary in 22 of 45 control cycles versus 2 of 49 rhIL-3 cycles (P less than .001). Platelet transfusions were required in 7 of 45 control cycles versus 3 of 50 rhIL-3 cycles (P less than .5). rhIL-3 up to 10 micrograms/kg/d could be administered without severe side effects. At 15 micrograms/kg/d, rhIL-3 headache was dose- limiting. Other side effects were fever, flu-like symptoms, nausea, skin rash, flushing, facial erythema, and urticaria. Liver toxicity occurred in rhIL-3 and control cycles. rhIL-3 slightly increased tumor necrosis factor alpha, C-reactive protein, and serum amyloid A plasma levels, whereas no effect on IL-6 plasma levels was observed. rhIL-3 administered SC appears to be an interesting hematopoietic growth factor for reduction of chemotherapy-induced myelotoxicity.
