PURPOSE: To evaluate the safety and efficacy of intravenous (IV) sodium ferric gluconate complex (FG), oral ferrous sulfate, or no iron to increase hemoglobin (Hb) in anemic cancer patients receiving chemotherapy and epoetin alfa. PATIENTS AND METHODS: In this open-label, multicenter trial, 187 patients with chemotherapy-related anemia (Hb <11 g/dl; serum ferritin > or =100 ng/ml or transferrin saturation > or =15%) scheduled to receive chemotherapy and epoetin alfa (40,000 U subcutaneously weekly) were randomized to 8 weeks of 125 mg of IV FG weekly, 325 mg of oral ferrous sulfate three times daily, or no iron. The primary outcome was a change in Hb from baseline to endpoint, first whole-blood or red blood cell transfusion, or study withdrawal. RESULTS: One hundred twenty-nine patients were evaluable for efficacy (FG, n = 41; oral iron, n = 44; no iron, n = 44). Mean increase in Hb was 2.4 g/dl (95% confidence interval [CI], 2.1-2.7) for FG (p = .0092 vs. oral iron; p = .0044 vs. no iron), 1.6 g/dl (95% CI, 1.1-2.1) for oral iron (p =.7695 vs. no iron), and 1.5 g/dl (95% CI, 1.1-1.9) for no iron. Hb response (increase > or =2 g/dl) was 73% for FG (p = .0099 vs. oral iron; p = .0029 vs. no iron), 46% for oral iron (p = .6687 vs. no iron), and 41% for no iron. FG was well tolerated. CONCLUSION: For cancer patients with chemotherapy-related anemia receiving epoetin alfa, FG produces a significantly greater increase in Hb and Hb response compared with oral iron or no iron, supporting more aggressive treatment with IV iron supplementation for these patients.