BACKGROUND Patients with anemia and lower-risk myelodysplastic syndromes in whom erythropoiesis-stimulating agent therapy is not effective generally become dependent on red-cell transfusions. Luspatercept, a recombinant fusion protein that binds transforming growth factor β superfamily ligands to reduce SMAD2 and SMAD3 signaling, showed promising results in a phase 2 study. METHODS In a double-blind, placebo-controlled, phase 3 trial, we randomly assigned patients with very-low-risk, low-risk, or intermediate-risk myelodysplastic syndromes (defined according to the Revised International Prognostic Scoring System) with ring sideroblasts who had been receiving regular red-cell transfusions to receive either luspatercept (at a dose of 1.0 up to 1.75 mg per kilogram of body weight) or placebo, administered subcutaneously every 3 weeks. The primary end point was transfusion independence for 8 weeks or longer during weeks 1 through 24, and the key secondary end point was transfusion independence for 12 weeks or longer, assessed during both weeks 1 through 24 and weeks 1 through 48. RESULTS Of the 229 patients enrolled, 153 were randomly assigned to receive luspatercept and 76 to receive placebo; the baseline characteristics of the patients were balanced. Transfusion independence for 8 weeks or longer was observed in 38% of the patients in the luspatercept group, as compared with 13% of those in the placebo group (P<0.001). A higher percentage of patients in the luspatercept group than in the placebo group met the key secondary end point (28% vs. 8% for weeks 1 through 24, and 33% vs. 12% for weeks 1 through 48; P<0.001 for both comparisons). The most common luspaterceptassociated adverse events (of any grade) included fatigue, diarrhea, asthenia, nausea, and dizziness. The incidence of adverse events decreased over time. CONCLUSIONS Luspatercept reduced the severity of anemia in patients with lower-risk myelodysplastic syndromes with ring sideroblasts who had been receiving regular red-cell transfusions and who had disease that was refractory to or unlikely to respond to erythropoiesisstimulating agents or who had discontinued such agents owing to an adverse event. (Funded by Celgene and Acceleron Pharma; MEDALIST ClinicalTrials.gov number, NCT02631070; EudraCT number, 2015-003454-41.)

Transfusion dependency seems to have a major prognostic impact in patients with myelodysplastic syndrome (MDS) (Malcovati L et al. J Clin Oncol2007;25:3503). Preliminary data also suggest that the development of iron overload could influence outcome (Malcovati L et al. J Clin Oncol2005;23:7594 and Garcia-Manero G et al. Leukemia2008;22:538), but small numbers have precluded a meaningful analysis of the prognostic value of this characteristic. The main aim of this study was to evaluate the independent prognostic value of transfusion dependency (as defined in WHO-based Prognostic Scoring System [WPSS]) and iron overload (defined as serum ferritin level &gt;1,000 ng/mL) in a large series of 2,994 patients (median age, 74 yr) with de novo MDS according to FAB criteria (2,107 MDS according to WHO criteria). Complete transfusional history was available in 2,241 patients (835 transfusion dependent [TD] at diagnosis, 526 TD during follow-up, and 880 non-TD) and serum ferritin levels in 1,634. Karyotyping was successfully performed in 2,074 patients, who could then be classified by the International Prognostic Scoring System (IPSS) as low (861 patients), intermediate-1 (748), intermediate-2 (311), and high-risk (154). The numbers of patients in the five risk categories defined by the WPSS (available for 1,228 patients) were 257 (21%) in very low, 385 (31%) in low, 217 (18%) in intermediate, 271 (22%) in high, and 98 (8%) in very high, closely similar to those reported in the original WPSS series. Actuarial curves of overall survival (OS) and risk of evolution to acute myeloblastic leukemia (AML) were built by Kaplan-Meier method and differences between curves compared with log-rank tests. Multivariate analyses of OS and risk of evolution to AML were performed by Cox proportional hazards regression method, with development of transfusion dependency and iron overload entered as time-dependent covariates. Other variables included in the prognostic factor analyses were age, gender, hemoglobin level, absolute WBC, PMN, and platelet counts, proportion of blasts in blood and marrow, percentage of dysplastic features in the three different hematopoietic cell lines, cytogenetics according to IPSS cytogenetic risk subgroups, FAB and WHO classifications, ferritin, beta-2 microglobulin, erythropoietin, and LDH levels at diagnosis, and IPSS and WPSS risk categories. All the previous variables showed a statistically significant relationship with OS and/or AML risk on univariante analyses. Median OS for TD patients at diagnosis, TD patients during evolution, and non-TD patients was 19, 60, and 96 months, respectively (P&lt;.0001). Multivariate analyses in a set of 902 cases with complete data confirmed that development of iron overload (1st variable selected to enter the model; hazard ratio [HR], 52.4; P&lt;.0001) and transfusion dependency (2nd to enter; HR, 8.8; P&lt;.0001) were strongly associated with OS and added significant independent prognostic information to that afforded by the IPSS and WPSS scores or by other characteristics with universally recognized prognostic value. Further, multivariate analyses of AML transformation risk showed that iron overload (1st to enter; HR, 6.6; P&lt;.0001) and transfusion dependency (2nd to enter; HR, 3.5; P=.003) had also independent impact on that endpoint. These results demonstrate for the first time the independent prognostic value of development of iron overload on OS and AML risk in MDS, confirm the impact of transfusion dependency on those outcomes, and support that the inclusion of both variables in a new prognostic scoring system would add clinically relevant information. They also suggest that avoiding or reducing iron overload by an appropriate chelation therapy could improve OS and reduce the risk of AML transformation in MDS patients.

This study aimed to evaluate the evolution of iron overload, assessed by serum ferritin (SF), in transfusion-dependent lower risk patients with myelodysplastic syndrome (MDS), as well as to describe the occurrence of organ complications, and to analyze its relationship with iron chelation therapy. This observational retrospective study was conducted from March 2010 to March 2011 in 47 Spanish hospitals. A total of 263 patients with lower risk MDS (International Prognostic Scoring System [IPSS] low/intermediate-1 risk or Spanish Prognostic Index [SPI] 0-1 risk), transfusion-dependent, and who had received ≥10 packed red blood cells (PRBC) were included. At MDS diagnosis, patients received a mean of 2.8 ± 3.9 PRBC/month, and 8.7% of patients showed SF ≥1000 μg/L. Over the course of the disease, patients received a mean of 83.4 ± 83.3 PRBC, and 36.1% of patients presented SF ≥2500 μg/L. Cardiac, hepatic, endocrine, or arthropathy complications appeared/worsened in 20.2, 11.4, 9.9, and 3.8% of patients, respectively. According to investigator, iron overload was a main cause of hepatic (70.0%) and endocrine (26.9%) complications. A total of 96 (36.5%) patients received iron chelation therapy for ≥6 months, being deferasirox the most frequent first chelation treatment (71.9%). Chelation-treated patients showed longer overall survival (p < 0.001), leukemia-free survival (p = 0.007), and cardiac event-free survival (p = 0.017) than non-chelated patients. In multivariable analyses, age (p = 0.011), IPSS (p < 0.001), and chelation treatment (p = 0.015) were predictors for overall survival; IPSS (p = 0.014) and transfusion frequency (p = 0.001) for leukemia-free survival; and chelation treatment (p = 0.040) and Sorror comorbidity index (p = 0.039) for cardiac event-free survival. In conclusion, these results confirm the potential survival benefit of iron chelation therapy and provide additional evidence on the deleterious effect of iron overload in lower risk MDS patients.

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A fixed dose of 300 μg of darbepoetin alfa weekly (with or without filgrastim) seems to be an effective and safe treatment for anemic patients with low or intermediate-risk MDS, low transfusion burden and EPO levels <500 IU/L. Results may not be extrapolable to unselected MDS patients.