A Real Life Survey On Erythropoietin Alpha Treatment In a Cohort Of 1049 Low Risk MDS Patients: An Italian MDS Registry Study

Erythropoiesis stimulating agents (ESAs) have been demonstrated to reduce the transfusion requirements in International Prognostic Scoring System (IPSS) low/Int-1 risk MDS patients and response to ESAs is associated with an improved quality of life. Response to ESAs varies from 20 to 60% according to the different studies and an association between ESAs response and a better overall survival (OS), without any disease evolution to AML has been reported. Aim of our study is to analyze the real life use of ESAs in Italy and to assess which group of lower risk MDS patients can benefit more by this treatment.

From 1999 to 30 Jun 2013, 2487 patients affected by MDS were included in the Network of the Italian MDS Registries. Morphological MDS diagnosis was confirmed. Among them, 1411 IPSS low/int-1 patients with follow-up data available were selected. Furthermore we excluded the following cases: 87 patients who were treated at any time by azacytidine (n=61) or lenalidomide (n=26), 95 patients with WHO 2002 diagnosis of CMML and aCML, 96 patients with incomplete data, 84 patients unhomogeneously treated with ESAs other than EPO alpha. We obtained a final data base of 1049 cases. OS and leukemic evolution (LE) according to EPO treatment were analyzed using the Kaplan-Meier product-limit survival curve estimates and log-rank tests.

Median age was 74 years, 59% of the patients were male and 41 % female. WHO 2002 classification was as follows: 296 (28 %) Refractory Anemia, 347 (33 %) refractory cytopenia with multilineage dysplasia, 94 (9%) refractory anemia with ringed sideroblasts, 46 (4 %) Del 5q, 188 (18 %) refractory anemia with excess of blasts and 78 (7 %) MDS unclassifiable. Median hemoglobin level at baseline was 10.0 g/dL. One hundred and twenty patients (11%) were previously transfused with a Hb baseline level less than 8.0 g/dL; 448 not yet transfused patients (43%) presented a mild anaemia with Hb ranging from 8 to 10 g/dL and 481 patients (46%) had a Hb level higher than 10 g/dL. Patients classification according to IPSS was as follows: low 55% (n=575); int-1 45% (n=474). 335 (32%) out of 1049 patients received EPO alpha treatment while the remaining 714 patients (68%) were supported without any ESAs treatment.

The rate of erythroid response to EPO therapy was 61%. Median duration of response was 82 weeks. The response rate to EPO was significantly higher in non transfused than in transfused patients: 69% versus 14% respectively (p value < 0.001).

Only 52 out of 1049 patients showed a LE and a higher incidence of LE in EPO treated patients was not observed.

Considering the whole group of patients, the OS of EPO treated patients was not statistically different from untreated ones. However EPO responders patients showed a better OS in comparison to both the non responders and non-EPO treated patients (p value < 0.05).

When we stratified patients according to the basal hemoglobin level (lower than 8 g/dL, from 8 to 10 g/dL and higher than 10 g/dL) in patients with Hb ranging from 8 to 10 g/dL we observed a significant improvement in OS following successful EPO treatment (median survival: EPO vs. non-EPO 64 vs. 43 months respectively; p<0.001). The response to EPO favorably affected the OS of patients with Hb level 8-10 g/dL in comparison to either non treated or non-responding patients. At the opposite the OS improvement by EPO therapy was minimum and it did not reach statistical significancy in either transfusion dependent patients with basal Hb < 8 g/dL and in patients with Hb > 10 g/dL. Even if adverse events were not prospectively recorded in the Registry, no frequent thromboembolic events was reported in EPO group in comparison to non treated patients.

Our survey can suffer from selection bias due to the limits typical of a voluntary-based registry, but it can be considered a good real life picture of EPO alpha therapy in lower risk Italian MDS patients. Our data confirm that EPOa treatment is globally safe and that patients who can benefit more are the mild anemic untransfused subjects, with baseline Hb level ranging from 8 to 10 g/dL.

Santini:Celgene: Honoraria; Novartis: Honoraria; GSK: Honoraria; Janssen: Honoraria.