Abstract: Introduction: Ph-negative myeloproliferative neoplasms (MPN) represent a heterogeneous group of hematological malignancies which differ in various aspects such as clinical manifestation, underlying genetic aberrations, cytomorphological features and life expectancy. However, across all subtypes, patients (pts) with MPN often suffer from severe symptoms, resulting in an impairment of the quality of life (QoL). Methods: The German Study Group for MPN (GSG-MPN) Bioregistry is a non-interventional prospective study including pts of at least 18 years with diagnosis of Ph-negative MPN according to WHO criteria (2008) having provided written informed consent. The Bioregistry study also includes assessment of QoL at baseline and on an annual basis, with all pts completing the standardized MPN-SAF-TSS questionnaire (German version) and an additional item indicating pts' subjective overall QoL on an 11-point Likert scale. Total scores range from 0 to 90 and were calculated if at least 6 items were answered (Emanuel RM et al., J Clin Oncol. 2012; 30 (33): 4098-103.)). Clinical variables, as documented in the registry, included comorbidities, reported symptoms as assessed by the physician, bleeding, and thromboembolic events (TEE). For statistical analysis, standard descriptive methods, Spearman correlation coefficient, Wilcoxon test/Kruskal-Wallis test for significance testing, and Kendall´s tau-b statistics were used. Results: 1,403 pts who had completed at least six items of the QoL assessment at baseline were included in this analysis. Median age at diagnosis was 58 years (interquartile range [IQR] 22), 98% were Caucasian, 50% were female. 494 pts were diagnosed with essential thrombocythemia (ET, 35%), 444 pts with polycythemia vera (PV, 32%), 302 pts with primary myelofibrosis (PMF, 22%), 83 pts with MPN-unclassifiable (MPNu, 6%), 43 pts with post-ET-myelofibrosis (pET-MF, 3%) and 37 pts with post-PV-myelofibrosis (pPV-MF, 3%). The most common complaint reported via the MPN-SAF-TSS was fatigue, occurring in more than 80% of the pts in all entities except MPNu (77%). More than 50 % of pts in each entity reported to suffer from early satiety, night sweats, concentration problems, or overall impairment of QoL. Table 1 summarizes all 9 symptoms and overall QoL from the questionnaire categorized by entity. Interestingly, the pts suffering from PET-MF reported the highest symptom burden, while PPV-MF pts showed the lowest overall symptom burden (median total QoL score of 23 vs. 16; p=0.01). The strongest correlations among the different symptoms were seen for fatigue and overall QoL (Spearman´s rho 0.57, p 〈 0.001) as well as concentration problems and overall QoL (Spearman´s rho 0.33, p 〈 0.001). Furthermore, the impact of variables such as age, comorbidities and TEE on QoL was assessed. Abdominal discomfort increased with age (rho = -0.14, p 〈 0.001). A history of TEE before baseline assessment correlated significantly with fatigue scores (Spearman rho= 0.07, p 〈 0.01) and with concentration problems (rho=0.07, p 〈 0.01). With an increasing number of TEE, scores for both of these items worsened over time (p 〈 0.01, respectively). Moreover, MPN-total score (MPN-TSS) was higher in pts with more comorbidities (Median: 18 (IQR:23), and 25 (27) for pts with 〈 3 versus ≥3 comorbidities, respectively, p= 0.017). Next, we compared data on 5 of the pts symptoms (reported in the questionnaire) to their assessment by the treating physician (only 5 items were available both in the questionnaire and in our registry database) in order to understand whether the "physician´s opinion" is congruent with the patient´s reported outcome in the questionnaire. While there were clear associations between the two data sources, there were also significant discrepancies, e.g., the physician did not indicate fatigue in about 20% of pts with self-assessed fatigue score of 〉 =6 points. The most concordant symptom was night sweats (further details in table 2). Conclusions: Most MPN pts suffer from a significant symptom burden which impairs their QoL. TEE influence fatigue and concentration problems. The perception of symptoms (particularly with respect to fatigue) differs between pts and treating physician which suggests that questionnaires should be used on a routine basis in order to faithfully reflect patient´s degree of suffering from MPN and/or treatment. Disclosures Isfort: Amgen: Other: i.e. travel support; Mundipharma: Other: i.e. travel support; Roche: Other: i.e. travel support; Incyte/Ariad: Consultancy; Pfizer: Consultancy, Honoraria, Other: i.e. travel support; BMS: Honoraria; Novartis: Consultancy, Honoraria, Other: i.e. travel support; Alexion: Other: i.e. travel support; Hexal: Other: i.e. travel support. Stegelmann:Novartis: Consultancy, Honoraria. Al-Ali:Gilead: Consultancy, Research Funding; Otsuka: Consultancy, Honoraria; Alexion: Honoraria; Novartis: Consultancy, Honoraria, Other: Travel support, Research Funding; Celgene: Honoraria, Other: Travel support, Research Funding. Goethert:BMS: Consultancy, Honoraria, Other: i.e. travel support; Incyte: Consultancy, Honoraria, Other: i.e. travel support; Pfizer: Consultancy, Honoraria; Novartis: Honoraria; Proteros Biostructures: Honoraria; AOP Orphan: Other: i.e. travel support. Haenel:Novartis: Honoraria; Takeda: Honoraria; Roche: Honoraria; Amgen: Honoraria. Platzbecker:Celgene: Research Funding. Griesshammer:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Brümmendorf:Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Takeda: Consultancy.

Abstract: Inflammation-induced thrombosis represents a severe complication in patients with myeloproliferative neoplasms (MPN) and in those with kidney dysfunction. Overlapping disease-specific attributes suggest common mechanisms involved in MPN pathogenesis, kidney dysfunction, and thrombosis. Data from 1420 patients with essential thrombocythemia (ET, 33.7%), polycythemia vera (PV, 38.5%), and myelofibrosis (MF, 27.9%) were extracted from the bioregistry of the German Study Group for MPN. The total cohort was subdivided according to the calculated estimated glomerular filtration rate (eGFR, (mL/min/1.73 m2)) into eGFR1 (≥90, 21%), eGFR2 (60–89, 56%), and eGFR3 ( 〈 60, 22%). A total of 29% of the patients had a history of thrombosis. A higher rate of thrombosis and longer MPN duration was observed in eGFR3 than in eGFR2 and eGFR1. Kidney dysfunction occurred earlier in ET than in PV or MF. Multiple logistic regression analysis identified arterial hypertension, MPN treatment, increased uric acid, and lactate dehydrogenase levels as risk factors for kidney dysfunction in MPN patients. Risk factors for thrombosis included arterial hypertension, non-excessive platelet counts, and antithrombotic therapy. The risk factors for kidney dysfunction and thrombosis varied between MPN subtypes. Physicians should be aware of the increased risk for kidney disease in MPN patients, which warrants closer monitoring and, possibly, early thromboprophylaxis.

Abstract: Introduction: Mutations (muts) in JAK2, MPL, and CALR are genetic hallmarks in myeloproliferative neoplasms such as myelofibrosis (MF). Prognostication in MF is predominantly based on clinical parameters according to the Dynamic International Prognostic Scoring System (DIPSS). However, gene mutations become increasingly important allowing for a more precised assessment of prognosis. For instance, CALR mutated MF is associated with favorable prognosis, while mutations in distinct high molecular-risk (HMR) genes are considered adverse. Our multicenter phase-Ib/II MPNSG-0212 trial (NCT01644110) investigating ruxolitinib plus pomalidomide in a total cohort of 92 patients with advanced MF and anemia provides an ideal basis for investigating the genomic landscape and molecular risk in a well-defined study population. Aims & Methods: To assess the genomic landscape in MF patients treated within the MPNSG-0212 trial and to correlate the results with clinical parameters and overall survival (OS). So far, targeted next generation sequencing (NGS) of 269 candidate genes was performed in peripheral blood or bone marrow from 81/92 patients using libraries prepared with SureSelectXT HS (Agilent, Santa Clara, USA). NGS was carried out on a NextSeq550 (Illumina, San Diego, USA). Results: At study entry, median age of the 81 patients was 71 years (range 52-86), median Hb 8.6 g/dL (range 5.4-11.7 g/dl); 30% of patients were RBC transfusion-dependent; 67% had primary MF (PMF) and 33% secondary MF (SMF), respectively. According to DIPSS, the vast majority of the patients were categorized as intermediate-2 (63%) or high-risk (26%) MF; 11% were low- and intermediate-1 risk patients. Overall, 315 muts were identified in 80/81 (99%) patients with a median of 3 muts/patient (range 0-9). Recurrent muts (≥5%) were identified in JAK2 (60%), ASXL1 (30%), SRSF2 (21%), CALR (20%; type-1: 75% [n=12], type-2 and non-type-1/2: 12.5% [n=2] each), MPL (19%), SF3B1 (19%), TET2 (16%), U2AF1 (15%), CBL and EZH2 (10% each), IDH2 and DNMT3A (7% each), PHF6, ZRSR2, and CUX1 (5% each). The majority of the patients (95%) was characterized by the presence of a driver mut in JAK2, CALR, or MPL; 4/81 patients (5%) were triple negative (Figure 1). JAK2mut was associated with TET2mut (p=.047), whereas muts in CALR and TET2 were mutually exclusive (p=.05). CALRmut patients had less co-muts than patients with JAK2/MPL muts (mean 2.5 vs. 4.1, p=.007) and were mutually exclusive with muts in the spliceosome regulating genes SRSF2, SF3B1, U2AF1, and ZRSR2 (p=.009). Compared to MF with mutated JAK2 or MPL, MF patients with mutated CALR had a longer median OS (not reached vs. 3.1 years; p=.04). With regard to high molecular risk (HMR) muts, n=56 were detected in 38 patients (47%), with 40% (15/38) of the patients harboring ≥2 HMR muts. The most commonly mutated HMR genes were ASXL1 (43%; 24/56), followed by SRSF2 (30%), EZH2 (14%), IDH2 (11%), and IDH1 (2%). MPLmut but not JAK2mut or CALRmut were significantly associated with HMR mut (p=.023). HMR mut patients harbored more co-muts than HMR wt patients (median 5 vs. 3; p & lt;.0001). There were no significant differences in the variables age, sex, WBC, Hb, PLT, or LDH level between patients with HMR mut and HMR wt MF. In univariate analysis, patients with HMR mut MF had shorter median OS (2.3 vs 3.7 years, p=.007). In multivariate analysis (HMR mut, age, DIPSS-category, SMF vs. PMF) a higher DIPSS-score (HR, 3.2; 95% CI, 1.5-7.0; p=.004) and muts in HMR genes (HR, 3.5; 95% CI, 1.5-8.1; p=.003) were significant adverse prognostic factors for OS. Conclusions: Our NGS data underline the genomic complexity of advanced MF. CALR mutations were only found in 20% of the patients that were characterized by less co-mutations, mutual exclusivity with spliceosome mutations, and with more favorable outcome suggesting a distinct disease biology. Almost 50% of patients showed mutations in HMR genes which were associated with an inferior OS in univariate and multivariate analyses. §Frank Stegelmann and Konstanze Döhner contributed equally to this work. Figure 1 Figure 1. Disclosures Koschmieder: Shire: Honoraria, Other; Alexion: Other: Travel support; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Ariad: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Geron: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; AOP Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Baxalta: Membership on an entity's Board of Directors or advisory committees, Other; Abbvie: Other: Travel support; CTI: Membership on an entity's Board of Directors or advisory committees, Other; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Image Biosciences: Other: Travel support; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karthos: Other: Travel support. Heidel: Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; CTI: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene/BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AOP: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Hochhaus: Bristol-Myers Squibb: Research Funding; Pfizer: Research Funding; Incyte: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding. Hebart: AbbVie: Honoraria; AstraZeneca: Honoraria; BMS: Honoraria; Janssen: Honoraria; Roche: Honoraria. Isfort: Alexion: Other: Travel reimbursement; Roche: Other: Travel reimbursement; Amgen: Other: Travel reimbursement; Mundipharma: Other: Travel reimbursement; Hexal: Other: Travel reimbursement; BMS: Honoraria; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Ariad: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel reimbursement; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel reimbursement. Reiter: AOP Orphan Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel support; Deciphera: Membership on an entity's Board of Directors or advisory committees, Other: Travel expenses; Abbvie: Membership on an entity's Board of Directors or advisory committees; Celgene/BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel support; Incyte: Membership on an entity's Board of Directors or advisory committees, Other: Travel expenses; Blueprint Medicines: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel expenses; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel expenses, Research Funding. Waller: Boehringer Ingelheim: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Mylan: Consultancy; Alvotech: Consultancy; Takeda: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees; Lilly: Membership on an entity's Board of Directors or advisory committees, Other: travel support; Chugai: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees, Other: travel support; Amgen: Membership on an entity's Board of Directors or advisory committees; IPSEN: Other: travel grant. Scheid: Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Goethert: Pfizer: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: Travel support; Incyte: Consultancy, Honoraria, Other: Travel support; zr pharma & : Honoraria; BMS: Consultancy, Honoraria, Other: Travel support; AOP Orphan Pharmaceuticals: Honoraria, Other: travel support; Proteros Biostructures: Consultancy. Schafhausen: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Swedish Orphan Biovitrum AB: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Honoraria, Membership on an entity's Board of Directors or advisory committees; Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Blueprint Medicines: Membership on an entity's Board of Directors or advisory committees. Radsak: Otsuka: Consultancy, Honoraria; Abbvie: Other: e.g. travel support; Astellas: Other: e.g. travel support; TEVA: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: e.g. travel support; Daiichi Sankyo: Consultancy, Honoraria, Other: e.g. travel support; Celgene/BMS: Consultancy, Honoraria, Other: e.g. travel support; Amgen: Other: e.g. travel support; Takeda: Consultancy, Honoraria; Incyte: Consultancy, Honoraria; Corat: Consultancy, Honoraria; Cogent Biosciences: Consultancy, Honoraria; JAZZ: Other: e.g. travel support. Gattermann: Takeda: Research Funding; Novartis: Honoraria; Celgene: Honoraria. von Bubnoff: Novartis: Honoraria; Takeda: Honoraria. Brümmendorf: Bristol Myers: Research Funding; Janssen: Honoraria; Novartis: Honoraria, Patents & Royalties, Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Repeat Diagnostics: Research Funding; Takepart Media: Honoraria. Döhner: Celgene: Honoraria, Research Funding; Agios: Honoraria, Research Funding; GEMoaB: Honoraria; Astex Pharmaceuticals: Honoraria; Astellas: Honoraria, Research Funding; Oxford Biomedica: Honoraria; Novartis: Honoraria, Research Funding; Jazz Pharmaceuticals: Honoraria, Research Funding; Janssen: Honoraria; Helsinn: Honoraria; Gilead: Honoraria; AstraZeneca: Honoraria; Abbvie: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria, Research Funding; Berlin-Chemie: Honoraria; Roche: Honoraria; Pfizer: Research Funding. Griesshammer: Amgen: Consultancy, Honoraria; AOP Orphan: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; CTI: Consultancy, Honoraria; Shire: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Astra Zeneca: Consultancy, Honoraria. Stegelmann: BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees. Döhner: Abbvie: Consultancy, Honoraria; Janssen: Honoraria, Other: Advisory Board; Jazz Roche: Consultancy, Honoraria; Daiichi Sankyo: Honoraria, Other: Advisory Board; Astellas: Research Funding; Celgene/BMS: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Agios and Astex: Research Funding. OffLabel Disclosure: Pomalidomide was shown to be active in patients with myelofibrosis in particular in the treatment of anemia (Tefferi et al 2009, Begna et al 2011, Mesa et al 2010)

Abstract: Background: Anemia remains one cardinal symptom associated with reduced quality of life (QoL) in patients (pts) with myelofibrosis (MF) which is normally not being addressed by ruxolitinib (RUX). In our previous MPNSG-0109 trial, single-agent pomalidomide (POM) improved cytopenia in 14% (POM 0.5 mg QD) and 29% (POM 2.0 mg QD) of MF pts, respectively. In the MPNSG-0212 study, we sought to investigate the potential synergism of RUX plus POM to improve anemia and QoL in MF pts. Study Design: MPNSG-0212 is an ongoing multicenter, open-label, single-arm phase-Ib/II trial with a target population of 90 pts following a two-stage design (NCT01644110). Pts 1-40 in cohort 1 (co1) were treated with RUX (10 mg BID) plus low-dose POM (0.5 mg QD), while pts 41-90 in cohort 2 (co2) receive a step-wise dose increase of POM from 0.5 mg to 1 mg and 2 mg QD after 3 and 6 28-day-cycles, respectively. Primary endpoints are safety of the combination therapy, anemia response after 12 cycles (according to IWG-MRT and RBC transfusion independence [RBC-TI] criteria), and clinical benefit (CB) defined as stable disease plus i) hemoglobin (Hb) increase ≥1 g/dL in pts with RBC-TI or ii) doubling of RBC transfusion intervals and/or iii) significant ( & gt;25%) improvement of QoL as measured by the MPN-SAF questionnaire. Main inclusion criterion is MF with anemia (Hb & lt;10 g/dL and/or RBC transfusion dependence [RBC-TD]). Pts suitable for allogeneic transplantation and pts with low platelet counts ( & lt;100/nL) are excluded. Results: At data cut-off (31-May-2019), 79 pts were included. Data from 67 pts were available for evaluation (co1, n=40; co2, n=27). Baseline characteristics of the pts were as follows: median age 72 years (range 49-84), prior treatment in 53% (RUX in 22%, POM in 4%), median Hb level at study start 8.6 g/dL (range 5.4-11.7), RBC-TD in 28%, median spleen diameter measured by ultrasound 17.7 cm (range 12-36), presence of constitutional symptoms in 76%, and 91% intermediate-2 (61%) or high-risk (30%) pts according to DIPSS; 55% of pts in co1 had ≥1 high molecular risk mutation (ASXL1, SRSF2, EZH2, and/or IDH1/2). Median number of cycles until data cut-off was 12 (range 2-63) in co1 and 11 (range 2-21) in co2. In total, 502 adverse events (AE) mainly grade 1/2 were recorded: AE grade 1/2 in & gt;20% of pts were fatigue (in 27% of pts), dyspnea (24%), diarrhea (22%), and muscle cramps (21%); AE grade ≥3 in & gt;3% of pts was Hb decrease in the first weeks of treatment occurring in 25% of pts. In total, 87 serious AE (SAE), were recorded: most common SAE (in ≥3 pts) were pneumonia (in 15% of pts), leukemic transformation (9%), worsening of general condition (6%), CNS ischemia, and sepsis (4% each); 7 SAE (in 10% of pts) were grade 5. Number or severity of (S)AE was not increased in co2. Treatment interruptions of RUX and/or POM were necessary in 11 pts (27%) of co1 and 3 pts (11%) of co2; 2 pts stopped treatment permanently due to hematotoxicity. Increase of the POM dose to 1 mg and 2 mg QD was feasible in the majority of pts after 3 and 6 cycles, respectively. In co1, 18/40 pts (45%) continued treatment beyond cycle 12 because of an objective anemia response (7/40, 18%: clinical improvement [CI, Hb increase ≥2 g/dL] n=5, partial remission and RBC-TI n=1 each) or CB (11/40, 27%): Hb increase ≥1 g/dL and/or doubling of RBC transfusion intervals (n=4) or improvement of QoL according to MPN-SAF (n=7). In co2, 17/27 pts (63%) reached cycle 12 and 10/17 (59%) continued treatment: 2/10 (20%) experienced CI, whereas 8/10 (80%) fulfilled the CB criterion; 19/27 pts (70%) were still on treatment at the time of data cut-off. Among all 67 pts analyzed, 42% (28/67) were on treatment for more than 12 cycles and 24% (16/67) for more than 24 cycles; 3 pts (4%) were treated for more than 60 cycles due to sustained response or CB. Of note, mean Hb increased from 8.7 g/dL at baseline to 9.6 g/dL at end of cycle 18 and remained stable thereafter (Figure 1). Conclusions: Combination treatment using RUX plus POM is feasible in pts with poor-risk MF and resulted in an objective anemia response rate of 18% in co1. Of note, 42% of pts were treated with & gt;12 cycles and showed a longer lasting stabilization of their disease with sustained improvement of Hb and QoL. Step-wise increase of the POM dose in co2 is safe and feasible with 70% of pts still on study treatment. Updated efficacy results of co2 with longer follow-up data will be presented at the meeting. Figure 1 Disclosures Stegelmann: Incyte: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Koschmieder:Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers-Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis Foundation: Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Ariad: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AOP Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; CTI: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Shire: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Isfort:Novartis: Consultancy, Honoraria, Other: Travel reimbursement; Pfizer: Consultancy, Honoraria, Other: Travel reimbursement; Ariad: Consultancy, Honoraria; BMS: Honoraria; Hexal: Other: Travel reimbursement; Amgen: Other: Travel reimbursement; Mundipharma: Other: Travel reimbursement; Roche: Other: Travel reimbursement; Alexion: Other: Travel reimbursement. Hochhaus:Pfizer: Research Funding; Novartis: Research Funding; BMS: Research Funding; Incyte: Research Funding; MSD: Research Funding. Göthert:Bristol-Myers Squibb: Consultancy, Honoraria, Other: Travel support; Incyte: Consultancy, Honoraria, Other: Travel support; Pfizer: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: Travel support; Proteros Biostructures: Consultancy; AOP Orphan Pharmaceuticals: Honoraria, Other: Travel support. Schafhausen:Incyte: Consultancy, Equity Ownership, Honoraria; Novartis: Consultancy, Honoraria. Radsak:Daiichi Sankyo: Other: Travel Support, Advisory Boards; Novartis: Other: Travel Support, Advisory Boards; JAZZ: Other: Travel Support; Celgene: Other: Travel Support, Advisory Boards; Takeda: Other: Advisory Boards; Otsuka: Other: Advisory Boards. von Bubnoff:Novartis: Research Funding. Reiter:Blueprint: Consultancy, Honoraria, Other: Travel reimbursement; Novartis: Consultancy, Honoraria, Other: Travel reimbursement, Research Funding; Deciphera: Consultancy, Honoraria, Other: Travel reimbursement. Döhner:Celgene, Novartis, Sunesis: Honoraria, Research Funding; AbbVie, Agios, Amgen, Astellas, Astex, Celator, Janssen, Jazz, Seattle Genetics: Consultancy, Honoraria; AROG, Bristol Myers Squibb, Pfizer: Research Funding. Griesshammer:Novartis: Consultancy, Honoraria, Speakers Bureau. Döhner:Daiichi: Honoraria; Jazz: Honoraria; Novartis: Honoraria; Celgene: Honoraria; Janssen: Honoraria; CTI Biopharma: Consultancy, Honoraria.