Eltrombopag for myelodysplastic syndromes or chronic myelomonocytic leukaemia with no excess blasts and thrombocytopenia: a French multicentre retrospective real-life study.

Despite a moderate prevalence in low-risk myelodysplastic syndromes (MDS) and chronic myelomonocytic leukaemia (CMML), thrombocytopenia remains a risk of severe bleeding and therapeutic options are still limited. There are only a few studies with eltrombopag (ELT), a thrombopoietin receptor agonist, in those patients. In this retrospective multicentre study, ELT was used in 50 patients with MDS and 11 with CMML, with no excess of marrow blasts and platelet counts of <50 × 109 /l in a 'real-life' situation. Platelet response occurred in 47 (77%) patients. The median (range) duration of response was 8 (0-69) months. None of the eight still responders who discontinued ELT had relapsed, at a median (range) of 16 (6-23) months after ELT discontinuation. Although 36% of the patients were anti-coagulated or anti-aggregated only 10% of patients had Grade ≥3 bleeding events. Thrombotic events were observed in six (10%) patients, who all but one had a medical history of arterial or venous thrombosis. Progression to acute myeloid leukaemia occurred in four (7%) patients. In this first 'real-life' study, ELT was effective and generally well tolerated in patients with MDS/CMML without excess blasts.

Targeted molecular characterization shows differences between primary and secondary myelofibrosis.

INTRODUCTION: In BCR-ABL1-negative myeloproliferative neoplasms, myelofibrosis (MF) is either primary (PMF) or secondary (SMF) to polycythemia vera or essential thrombocythemia. MF is characterized by an increased risk of transformation to acute myeloid leukemia (AML) and a shortened life expectancy. METHODS: Because natural histories of PMF and SMF are different, we studied by targeted next generation sequencing the differences in the molecular landscape of 86 PMF and 59 SMF and compared their prognosis impact. RESULTS: PMF had more ASXL1 (47.7%) and SRSF2 (14%) gene mutations than SMF (respectively 27.1% and 3.4%, P = .04). Poorer survival was associated with RNA splicing mutations (especially SRSF2) and TP53 in PMF (P = .0003), and with ASXL1 and TP53 mutations in SMF (P < .0001). These mutations of poor prognosis were associated with biological features of scoring systems (DIPSS and MYSEC-PM score). Mutations in TP53/SRSF2 in PMF or TP53/ASXL1 in SMF were more frequent as the risk of these scores increased. This allowed for a better stratification of MF patients, especially within the DIPSS intermediate-1 risk group (DIPSS) or the MYSEC-PM high risk group. AML transformation occurred faster in SMF than in PMF and patients who transformed to AML were more SRSF2-mutated and less CALR-mutated at MF sampling. CONCLUSIONS: PMF and SMF have different but not specific molecular profiles and different prognosis depending on the molecular profile. This may be due to differences in disease history. Combining mutations and existing scores should improve prognosis assessment.

Apixaban for the prevention of thromboembolism in immunomodulatory-treated myeloma patients: Myelaxat, a phase 2 pilot study.

The risk of venous thromboembolism (VTE) is higher in myeloma patients receiving immunomodulatory compounds. A VTE prophylaxis using low-molecular-weight heparin or aspirin is therefore proposed. Apixaban is an oral direct anti-Xa. Several studies have shown the efficacy and safety of apixaban in VTE prophylaxis compared to enoxaparin. The objective of this prospective phase 2 pilot study was to assess the risk of VTE and bleeding in patients with myeloma treated with immunomodulatory compounds lenalidomide (len) or thalidomide (thal), using apixaban in a preventive scheme. Myeloma patients requiring Melphalan-Prednisone-Thalidomide in the first line, or Lenalidomide-Dexamethasone in the relapse setting received apixaban, 2.5 mg x 2/day for 6 months. Venous (pulmonary embolism-PE, or symptomatic proximal or distal deep vein thrombosis-DVT, or all proximal asymptomatic events detected by systematic proximal bilateral compression ultrasound) or arterial thrombotic events, and bleeding events (ISTH 2005) were registered. One hundred and four patients were enrolled (mean age 69.8 ± 7.8 years), 11 in first line and 93 in relapse. Two venous thrombotic events were observed, for example, an asymptomatic proximal DVT and a symptomatic distal DVT, in the context of apixaban stopped 14 days before, due to lenalidomide-induced thrombocytopenia. No PE or arterial cardiovascular events were reported. Only one major and 11 CRNM hemorrhages were reported. These data must now be confirmed on a randomized large study.

Mutations affecting mRNA splicing define distinct clinical phenotypes and correlate with patient outcome in myelodysplastic syndromes.

A cohort of MDS patients was examined for mutations affecting 4 splice genes (SF3B1, SRSF2, ZRSR2, and U2AF35) and evaluated in the context of clinical and molecular markers. Splice gene mutations were detected in 95 of 221 patients. These mutations were mutually exclusive and less likely to occur in patients with complex cytogenetics or TP53 mutations. SF3B1(mut) patients presented with lower hemoglobin levels, increased WBC and platelet counts, and were more likely to have DNMT3A mutations. SRSF2(mut) patients clustered in RAEB-1 and RAEB-2 subtypes and exhibited pronounced thrombocytopenias. ZRSR2(mut) patients clustered in International Prognostic Scoring System intermediate-1 and intermediate-2 risk groups, had higher percentages of bone marrow blasts, and more often displayed isolated neutropenias. SRSF2 and ZRSR2 mutations were more common in TET2(mut) patients. U2AF35(mut) patients had an increased prevalence of chromosome 20 deletions and ASXL1 mutations. Multivariate analysis revealed an inferior overall survival and a higher AML transformation rate for the genotype ZRSR2(mut)/TET2(wt) (overall survival: hazard ratio = 3.3; 95% CI, 1.4-7.7; P = .006; AML transformation: hazard ratio = 3.6; 95% CI, 2-4.2; P = .026). Our results demonstrate that splice gene mutations are among the most frequent molecular aberrations in myelodysplastic syndrome, define distinct clinical phenotypes, and show preferential associations with mutations targeting transcriptional regulation.

Lenalidomide in lower-risk myelodysplastic syndromes with karyotypes other than deletion 5q and refractory to erythropoiesis-stimulating agents.

Lenalidomide (LEN) has been shown to yield red blood cell (RBC) transfusion independence in about 25% of lower risk myelodysplastic syndromes (MDS) without del(5q), but its efficacy in patients clearly refractory to erythropoiesis-stimulating agents (ESA) is not known. We report on 31 consecutive lower-risk non-del(5q) MDS patients with anaemia refractory to ESA and treated with LEN in a compassionate programme, 20 of whom also received an ESA. An erythroid response was obtained in 15 patients (48%), including 10 of the 27 (37%) previously transfusion-dependent (RBC-TD) patients, who became transfusion-independent (RBC-TI). Nine of the responders relapsed, whereas 6 (40%) were still responding and transfusion-free after 11(+)-31(+) months. Median response duration was 24 months. The erythroid response rate was lower in refractory cytopenia with multilineage dysplasia (27% vs. 60%) and tended to be higher in patients treated with LEN + ESA (55% vs. 36%). Response duration was significantly longer in responders who obtained RBC-TI and in patients treated with LEN after primary resistance to ESA. The main toxicity of LEN was cytopenias. We confirm that, in a patient population of lower risk MDS without del 5q clearly resistant to ESA, LEN is an interesting second line therapeutic option. Its combination with ESAs in this context warrants prospective studies.

Treatment of myelodysplastic syndromes with excess of blasts by bevacizumab is well tolerated and is associated with a decrease of VEGF plasma level.

Myelodysplastic syndromes (MDS) are associated with increased bone marrow vascularity and increased levels of various angiogenic factors including Vascular Endothelial Growth Factor (VEGF) which is implicated in the proliferation and survival of leukemic cells. Before the approval of hypomethylating agents in this indication, the GFM conducted a multicenter phase II trial testing the efficacy and tolerance of bevacizumab, a humanized monoclonal antibody against VEGF, in MDS with excess of marrow blasts and its impact on bone marrow angiogenesis. Twenty-one patients were enrolled (16 males and five females) with a median age of 70 years and 19 were evaluable for haematological response after treatment (5 mg/kg IV every 2 weeks for 12 weeks). WHO diagnosis at baseline was RAEB-1 (38%) and RAEB-2 (62%). Treatment was well tolerated and was associated with significant decrease of VEGF plasma level [median (low quartile-high quartile)] from 65.5 pg/ml [LQ (low-quartile)-HQ (high quartile), 35.3-87.3 to 30.4 pg/ml (LQ-HQ, 22.5-34.0 pg/ml)] (p < 0.01) and reduction of bone marrow angiogenesis from a median of 20 vessels/mm(3) (LQ-HQ, 16.5-33 vessels/mm(3)) to 15.5 vessels/mm(3) (LQ-HQ, 10-23.2 vessels/mm(3)) (p = 0.03). On the other hand, only one patient had a significant haematological response with achievement of RBC transfusion independence. Thus, although bevacizumab had a significant impact on VEGF levels and angiogenesis in our patients, very few responses were seen when this drug was used as single agent. Given its good tolerability profile, however, combination of bevacizumab with other drugs, especially hypomethylating agents, could be considered in MDS.