Pentoxifylline and ciprofloxacin in patients with myelodysplastic syndrome. A phase II trial

Tumor necrosis factor (TNF) inhibits hematopoietic cell proliferation. The combination of pentoxifylline (PTX) and ciprofloxacin (Cipro) has been previously shown to reduce circulating serum levels of TNF. In this Phase II trial 14 patients with advanced myelodysplastic syndrome were treated with PTX (2,000 mg/day) and Cipro (1,000 mg/day) in order to determine tolerability and effect on peripheral blood cell counts, progenitor cell responsiveness to cytokines and circulating serum levels of interleukin-6 (IL6) and TNF. Toxicity attributed to PTX and Cipro were limited to nausea in 4 patients. Peripheral blood cell counts, platelet transfusion requirements and red blood cell transfusion requirements did not change during administration of PTX and Cipro (daily for 28 days). Marrow progenitor cells of patients entered into trial were less responsive to stimulation with cytokines in vitro at baseline and during the trial compared to normal volunteers. Eight patients had elevated IL6 levels before treatment with PTX and Cipro these levels did not change during therapy. Five patients had elevated TNF levels at baseline. There was a suggestion of decreased TNF levels during treatment with PTX and Cipro (P = .09). In conclusion, PTX and Cipro was well tolerated but no evidence of efficacy was observed.