Treatment of anaemia in myelodysplastic syndromes with prolonged administration of recombinant human granulocyte colony-stimulating factor and erythropoietin

Treatment with recombinant human erythropoietin (rhEPO) improves anaemia in approximate to 20% of the patients with myelodysplastic syndromes (MDS), R ecent reports suggest that a combination treatment with rhEPO plus recombin ant human granulocyte colony-stimulating factor (rhG-CSF) given for up to 1 8 weeks may result in a higher erythroid response rate than with rhEPO alon e. We investigated the potential advantage of an even more prolonged schedu le of combined rhG-CSF and rhEPO treatment to obtain and maintain stable re sponses, In a phase II study, 33 patients with MDS [17 with refractory anae mia (RA), eight with RR with ringed sideroblasts (RARS), eight with RA with excess blasts (RAEB) with bone marrow blast counts less than 20%] were sch eduled to receive at least 36 weeks of combined therapy with rhG-CSF and rh EPO. Seventeen of 28 evaluable patients demonstrated an erythroid response [61%: 95% confidence interval (CI) 41-78] after 12 weeks of treatment. The erythroid response rate was 80% (20 of 25 evaluable patients: 95% CI 59-93) after 36 weeks. Seven of these responses developed between week 12 and wee k 36, whereas two initially responding patients became refractory The cytok ine therapy was generally well tolerated. Nineteen of the 20 patients respo nding after 36 weeks continued to be treated with both cytokines. After 1 y ear and 2 years of continuous combined treatment, 50% of the initially incl uded patients showed a continuing response. Our results suggest that a prol onged combination treatment with rhG-CSF and rhEPO is highly effective in a chieving a stable and long-lasting erythroid response in many patients with MDS and low blast count.