ALBERT

Description: Abstract 255 Introduction: Standard treatment of acute myeloid leukemia (AML) comprises one or two cycles of chemotherapy to induce complete remission (CR) followed by postremission treatment in order to prevent relapse of the disease (consolidation therapy). In 2003, we initiated a prospective multicenter randomized trial to investigate the impact of different consolidation strategies on long-term outcome in AML patients ≤ 60 years. Consolidation options comprised upfront allogeneic stem cell transplantation (allo SCT) in aplasia after induction therapy, autologous SCT, and three cycles of standard high-dose-cytarabine-based consolidation. For patients receiving high-dose cytarabine, the main study aim was to evaluate the benefit of adding additional mitoxantrone and amsacrine to cytarabine consolidation. Design: From 2003 to 2009, 1182 patients (median age, 48 years; range 16–60 years) with untreated AML were randomly assigned at diagnosis to different consolidation strategies after classical 7+3 induction. According to the risk-adapted treatment strategy of the trial, cytogenetically or molecular intermediate-risk (IR) and adverse-risk (AR) patients should receive an allo SCT as consolidation treatment if an HLA-identical-sibling donor (IR) or HLA-matched related or unrelated donor (AR) was available. IR and AR patients with no available donor should receive autologous SCT. All favorable risk patients and patients with no available donor were scheduled for high-dose cytarabine based consolidation. Half of the patients were randomized for high dose cytarabine based consolidation. Half of the patients were randomized for high dose cytarabine alone while the other half received high dose cytarabine with the addition of amsacrine and mitoxantrone. Standard chemotherapy consisted of three cycles with high dose cytarabine (2 × 3 g/m2, day 1,3,5) whereas combined consolidation contained two cycles of MAC (cytarabine 2 × 1g/m2, day 1–6, mitoxantrone 10 mg/m2, day 4–6) plus one cycle of MAMAC (cytarabine 2 × 1 g/m2, day 1–5, amsacrine 100 mg/m2, day 1–5). In order to evaluate the effect of the two cytarabine based consolidation strategies, we determined overall survival (OS) and event free survival (EFS) using the method of Kaplan Meyer. Survival distributions were compared using the log rank test. Results: 1182 patients were randomized for further intervention (Arm A+B: n=582, 49.3%; Arm C+D: n=600, 50.7 %). Median follow-up was 41.4 months (95%-CI 39.3–43.6). A total number of 375 patients received allogeneic (n=322) or autologous SCT (n=53) and 807 patients were consolidated with cytarabine. Of these patients, 407 were randomized for cytarabine alone and 400were randomized to receive cytarabine plus mitoxantrone and amsacrine (MAC/MAC/MAMAC). Complete remission rate (CR) after second induction therapy was 59.1% (n=698). Between the four arms, there were no significant differences of the CR rates. Five-year OS of patients receiving high dose cytarabine alone was 47.1% (95%-CI 42.0–52.2%), for patients receiving MAC/MAMAC as consolidation therapy it was 46.8% (95%-CI 42.3–51.3%; p = 0.610). Three-year event free survival (EFS) was also not significant with 30.5% (95%-CI 26.6–34.4%) for patients receiving high dose cytarabine alone and 35.6% (95%-CI 31.7–39.5%; p = 0.059) for patients receiving MAC/MAMAC. Conclusions: According to our data, the addition of mitoxantrone and amsacrine to high dose cytarabine consolidation confers no benefit for treatment outcome in younger AML patients. Disclosures: No relevant conflicts of interest to declare.

Description: We started a prospective randomized multicenter trial to examine the importance of the infusion schedule of Ara-C as part of the Mito-FLAG regimen in patients (pts) with relapsed or primary refractory acute myeloid leukemia (AML). The treatment consisted of mitoxantrone (7 mg/m2, days 1/3/5), fludarabine (15 mg/m2, q-12h, days 1–5), Ara-C as bolus (B) (1000 mg/m2 over 1 h, q-12h, days 1–5) or continuous infusion (CI) (125 mg/m2 over 24 h, days 1–5) and G-CSF (5 μg/kg/day, day 0 until a neutrophile count of 0.5 × 109/μl). Since 11/1999, 253 pts from 36 centers in Germany entered the study (131 men, 122 women, aged 19–75 years, median 59 years). 131 pts (52%) showed a primary refractory AML or had relapsed within 6 months after 1st complete remission (CR), whereas 120 pts had suffered their 1st relapse after 6–18 months (79 pts/31%) or later (41 pts/16%). Only 2 pts with a 2nd relapse were enrolled. The diagnoses according to FAB criteria were as follows: M0 - 17 pts, M1 - 55 pts, M2 - 71 pts, M3 - 2 pts, M4 - 44 pts, M5 - 27 pts, M6 - 9 pts, M7 - 2 pts, 26 pts were not classified. 62 pts (25%) had a poor risk karyotype (defined as aberrations on the chromosomes 5, 7, 8 or multiple). In 50 pts (20%) an elevated leukocyte count (〉 20 × 109/μl) was observed. 22 pts (9%) had relapsed after prior hematopoietic stem cell transplantation (HSCT). Currently 249 pts are evaluable for response and 231 pts for toxicity and survival. Following Mito-FLAG, 120 pts (48%) achieved CR and 43 pts (17%) partial remission (PR), for an overall response rate of 65%. 206 pts experienced at least one episode of febrile neutropenia with a median duration of 8 (1–53) days. 19 pts (8%) suffered an early death because of toxicity (n=11) or progressive AML (n=8). Out of 163 responders, 8 pts were consolidated by high-dose therapy with autologous HSCT and 48 pts underwent allogeneic HSCT after dose-reduced conditioning. With a median follow-up of 40.2 months (0–93), the probabilities of event-free survival (EFS) and overall survival (OS) after 3 years were 13% and 19%, respectively. In responding pts the median duration of EFS and OS were 8.4 and 10 months, the 3-year-rates of EFS and OS were 28% and 33%, respectively. In conclusion, Mito-FLAG is an effective and well tolerated regimen in the salvage therapy of pts with AML.

Description: Background Chronic myeloid leukemia (CML) stem cells are inherently insensitive to tyrosine-kinase inhibitors (TKI). However, an important minority of CML patients was shown to discontinue TKI without experiencing molecular relapse. Underlying mechanisms are currently unknown. Plasmacytoid dendritic cells (pDCs) are critical regulators of immune responses. Following activation, pDC upregulate MHC-class II and other DC activation markers such as CD86 (also known as B7.2). CD86 is a co-stimulatory molecule during T-cell activation, but also ligand of the inhibitory immune checkpoint receptor CTLA-4, which counteracts T-cell activation. The origin and function of pDC in CML biology is unknown. Within a sub-study of the EUROSKI TKI discontinuation trial we prospectively tested the hypothesis that pDC counts and CD86 expression status govern relapse risk following TKI discontinuation. Methods: Using flow cytometry, cell sorting and fluorescence in situ hybridization (FISH), CD86 expression and BCR-ABL status were analyzed in PDCA-2+/CD123+ peripheral blood (pB) pDC of untreated CML patients (CML pDC), normal donors and 123 patients, who had stopped TKI therapy in deep molecular remission within the international EUROSKI study (EUDRACT 2011-000440-22). All 123 EUROSKI patients had given written informed consent to participate in the immunological sub-study of the EUROSKI trial. Fresh samples from 19 EUROSKI centers in Germany were centrally analyzed prior, as well as 1, 2, 3 and 6 months after TKI discontinuation. PB CD86+ pDC counts were calculated per 105 cells in the lymphocyte gate. Decision trees and 10-fold cross validation were employed to establish relapse prediction accuracy for this value. Results CML pDC were BCR-ABL-FISH positive (median: 81%; range, 57 to 100%). In contrast, the proportion of CD86+ CML pDC varied substantially (median: 25.9%, range 3.2% to 82.4%), suggesting that CD86 expression on CML pDC was not a direct consequence of oncogenic BCR-ABL signaling. This was confirmed experimentally in a murine CML model. In contrast to CML pDC, remission pDC were always BCR-ABL FISH negative (n=10), but still displayed a comparable high proportion of CD86 positive pDC (median: 21%; range, 2.2% to 62%). In contrast, normal donor pDC were rarely CD86 positive (median: 6.8%; range, 4.2% to 17%), reinforcing the aberrant, and BCR-ABL-independent nature of CD86 expression on CML and remission pDC. As a result, healthy donors displayed only between 26 to 84 CD86+ pDC per 105 lymphocytes, whereas EUROSKI remission patients exhibited between 6 to 309 CD86+ pDC per 105 lymphocytes. Based on the important role of CD86 as a high affinity ligand of the inhibitory immune checkpoint receptor CTLA-4, we next asked, whether CD86+ pDC counts are associated with relapse risk after TKI discontinuation. Strikingly, statistical models suggested that a CD86+ pDC count below or above 95 CD86+ pDC/105 lymphocytes optimally separated two relapse categories of EUROSKI patients. Whereas relapse free survival (RFS) (loss of MMR) for patients with more than 95 CD86+ pDC/105 lymphocytes was 30% (n=32), RFS was 69% for patients (n=91) with less than 95 CD86+ pDC/105 lymphocytes (p

Description: Purpose: This multicenter study investigated the efficacy and safety of high-dose methotrexate (HD-MTX) induction followed by high-dose busulfan/thiotepa with autologous stem-cell transplantation (HD-BuTT) and response-adapted whole-brain radiotherapy (WBRT) in patients with newly diagnosed primary CNS lymphoma. Patients and methods: 23 patients (median age 55 years) were treated in five centres. Patients received HD-MTX (4h-infusion; 8g/m2; 〉60y: 6g/m2) on d1 and d10 followed by leucapheresis. Then patients were stratified according to their results on neuroimaging: In case of at least a partial response, HD-BuTT consisting of 16mg busulfan / 10mg thiotepa per kg body weight followed by peripheral stem cell transplantation was given. Patients without response to induction or without complete response after high-dose therapy received WBRT (45Gy) as further treatment. Results: 16 patients received the planned treatment with HD-MTX followed by HD-BuTT. CR / PR rates for these patients were 19 % / 69 % after HD-MTX, 69 % / 13 % after HD-BuTT, 81 % / 6 % after HD-BuTT plus WBRT, respectively. Included the patients with early WBRT due to toxicity (n=2) and non-responders to HD-MTX induction (n=4) the overall response rate for all 23 patients was 83 % (intention-to-treat). Outcome was significantly influenced by the response to MTX-induction. There were three treatment-related deaths. Irradiated patients (n=9) had a high incidence of severe neurotoxicity leading to death in 3 patients. At a median follow-up of 15 months the median EFS and OS for all patients were 17 and 20 months, after HD-BuTT 27 months and “not reached”, respectively. Patients older than 60 years and younger patients have achieved similar outcomes. Conclusion: This study showed that HD-methotrexate induction followed by HD-BuTT is a feasible treatment option for newly diagnosed primary CNS lymphoma. Patients achieving CR after HD-BuTT show no signs of clinical neurotoxicity with median survival not reached yet. Time on treatment is 2–3 months only, but the induction treatment needs improvement to be more effective. WBRT in this study was associated with a high incidence of severe neurotoxicity and should therefore be avoided.

Description: Introduction: The ELN classification of cytogenetic aberrations in acute myeloid leukemia (AML) distinguishes favorable risk, intermediate risk I and II and adverserisk. The adverse-risk group contains patients (pts) with inv(3) and t(3;3). These pts have a significantly poorer outcome compared to other cytogenetic aberrations. The MRC classification considers both pts with inv(3) and t(3;3) as well as patients with other abn(3q) as adverse risk, but excludes t(3;5). Pts with inv(3) or t(3;3) have breakpoints located on the long arm of chromosome 3 at q21 and q26. As a result of these chromosomal modifications, an enhancer-protein is deregulated and the stem-cell regulator zinc finger protein EVI1 on 3q26 is over expressed. Other 3q aberrations do not involve EVI1. We conducted a comparative analysis on the impact of abn(3q) with likely EVI1 alteration versus abn(3q) without EVI1 involvement. Analyses were done both in the entire group of abn(3q) pts and in the subgroup of pts treated with allogeneic hematopoietic stem-cell transplantation (HSCT). Methods: We performed a retrospective analysis on 163 patients with an abnormality on the q arm of chromosome 3 (abn(3q)). These pts were treated between 1996 and 2009 in three multicenter studies by the German SAL study group (AML2003, AML96, AML60+). Pts with t(3;5) were excluded (n=11). The remaining 152 patients were divided into two groups. Group 1 (EVI1) contained 56 patients with a chromosomal aberration likely to alter EVI1, i.e. t(3;3), inv(3) and abn(3)(q26). Group 2 (noEVI1) comprised the remaining 96 patients displaying other abn(3q) aberrations. We compared groups for baseline characteristics, complete remission (CR), relapse-free survival (RFS) and overall survival (OS) in total and stratified for treatment. Results: Descriptive comparison of the groups (EVI1 vs noEVI1) revealed a significantly higher WBC count (14.3 vs 4.6 Gpt/l), PLT count (62 vs 47 Gpt/l) and -7 incidence (29% vs 16%) in the EVI1 group, whereas in the noEVI1 group, complex aberrations (25% vs 74%) and 17p alterations (0% vs 24%) occurred in a higher proportion of pts. CR rates (52% vs 47%), median RFS (7 vs 6 months) and median OS (6 vs 7 months) did not differ significantly between the two groups. In order to explore the clinical behavior of the different abn(3q) aberrations in relation to allogeneic HSCT, we compared EVI1 pts (n=21) versus noEVI1 pts (n=38) who received an allogeneic HSCT at any time during treatment. Patients with aberrant EVI1 were significantly younger (median age 44 vs 52 years), had a higher incidence of -7 (29% vs 13%), but less frequent karyotype complexity (10% vs 74%) or 17p alterations (0% vs 24%). More patients in the EVI1 group achieved a first CR before HSCT (95% vs 84%). Amongst CR pts, median RFS was slightly higher in the EVI1group (9 vs 6 months). In all abn(3q) pts with allogeneic HSCT, median OS was 30 months in the EVI1 group and only 12.5 months in the noEVI1 group. According to the log-rank test, this difference did not reach statistical significance (p=0.137). The advantage in mean OS for EVI1 patients is most likely due to the higher proportion of patients transplanted in CR while the accumulation of complex karyotypes in the noEVI1 group caused more primary resistant AML cases with a rapid progression even after allogeneic HSCT. Conclusions: Although AML development may be based on different molecularbiological mechanisms in patients with different abn(3q) aberrations depending on EVI1 alteration, the prognosis of the two groups is very similar. The most likely reason is the equal balance of favorable and adverse prognostic factors between the two groups such as age, karyotype complexity, 17p alteration and -7. Patients of both groups benefit from allogeneic HSCT to a similar extent. Confirmation of these results on larger data sets is desirable and under way. Disclosures Baldus: Novartis: Research Funding. Einsele:Novartis: Consultancy, Honoraria, Speakers Bureau; Amgen/Onyx: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau. Thiede:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AgenDix GmBH: Equity Ownership.

Description: The prognosis of AML in patients (pts) 〉60 years (y) is poor and there is no universally accepted standard approach. After induction chemotherapy (IC), a complete remission (CR+CRi) rate of 56.4% and a mortality of 21% at day (d) 90 are expected (Niederwieser et al, ASH 2012). Azacitidine (AZA) yields a one-year survival (OS) rate of 46.5% in pts 〉65 y and 〉30% marrow (BM) blasts (Dombret et al, Blood 2015). Yet, AZA and IC are not mutually exclusive. First results of the interim analysis of the DRKS00004519 (RAS-AZIC) study which evaluates priming with AZA followed by AZA or IC in pts 〉60 y with AML are presented. Patients and methods: Major inclusion criteria are newly diagnosed AML with marrow blasts 〉20% by aspiration or biopsy irrespective of WBC count, age 〉60 y, and eligibility for IC. Secondary AML from an antecedent hematologic disorder and therapy-related AML are not excluded. In the phase I part of the trial, safety of priming with AZA (75 mg/m2/day s.c) for 7 d followed by IC (Mitoxantrone 10 mg/ m2/day d 1-3 and cytarabine 1 g/m2/BID d 1, 3, 5, 7) on d 17 was established through a 3+3 design. In the multicenter phase II part (figure), priming was sequentially followed by AZA or IC based on d 15 BM blasts and d 56 response which were identified as early predictors for long-term response to AZA in AML (Al-Ali et al., Leuk Lymph 2012). The primary objective is overall response (OR) which includes CR, CRi, and PR at d 90 according to the International Working Group criteria (Cheson et al, J Clin Oncol 2003). Safety, OS, and mortality were secondary end points. According to the optimal two-stage design (Simon, Control Clin Trials 1989), an expected OR of 61% at the end of trial was estimated. Thus in a first stage analysis, 〈 19 of consecutive 40 (47.5%) pts not achieving the primary objective would be considered an indication for inferiority of the protocol treatment compared to standard IC. Hence, an interim analysis of the first stage was planned per protocol while accrual continues to include the first 40 pts who received the maximal tolerated priming dose of AZA. The trial is supervised by an independent Data Monitoring Committee. Adverse events (AEs) are reported according to the NCI CTCAE 4.03. All pts gave written informed consent. Results: Patient characteristics are shown in table 1. Median age is 69 y and median blast count 39%. All pts received priming with AZA. Median BM blasts at d 15 was 27% (range 2.4-88%). To date, data on subsequent therapies are captured in 33 (82.5%) pts. Except for one (withdrew consent on d 27), all pts received protocol assigned treatment based on BM blasts on d 15 [17/32 (53%) continued with AZA, 15/32 (47%) received IC]. Likewise, 26/32 (81%) pts ([2x data not yet available, 2x death (d 34; d 53), and 2x physician's choice] received response-adapted treatment on d 56 [12/26 (46%) started AZA maintenance and 14/26 (55%) received IC]. OR at d 90 for the 26 as yet evaluable pts is 80.7% [CR (61.5%, n=16); CRi (11.5%, n=3); PR (7.7%, n=2). No additional mortality till d 90 was reported. For the entire cohort, 85% of pts are alive after a median follow-up of 6 months. AEs were consistent with the known safety profile of AZA and IC. AEs 〉 grade 3 were reported 83x in 20 (50%) pts being mainly infectious and respiratory complications (60%). As expected, the majority (57%) were reported under IC, followed by 19% and 17% under priming and the 2. AZA cycle respectively. AEs led to postponement of the planned therapy in 6 pts (3x IC on d 17, 2x 2. AZA, 1x IC on d 56). The final assessment of the interim analysis is set in the near future. Conclusions: These data imply that in a heterogeneous disease like AML, integrating epigenetic therapy with chemotherapy in elderly pts in an individualized response-based approach is feasible, induces responses at least comparable to those seen after IC, and is associated with a remarkable low mortality. The definitive response rate and the impact of such an approach on survival will be answered at the end of the trial. Table 1. Patient characteristics (n=40) Median age, range (years) 69 ( 61 - 82) Male/Female (%) 55 / 45 Baseline ECOG (%)0/1/2 21 / 63 / 16 Type of AMLDo novo/secondary (%) 61 /39 Median WBC (range) x 109/L 6.7 (0.7 - 81.8 ) Median bone marrow blasts (aspiration) (range) (%) 39 (13 - 90) Cytogenetics (n=35)Normal/intermediate/unfavourable (%) 54 /23 / 23 FLT3+ (n=34) (%) 9 NPM1 + (n=34) (%) 9 Figure 1. Figure 1. Disclosures Al-Ali: Novartis: Consultancy, Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Off Label Use: Azacitidine is not approved for the use in patients with AML and blasts 〉 30% outside clinical trials.

Description: In patients with relapsed or refractory (r/r) Acute Myeloid Leukemia (AML), allogeneic Hematopoietic Stem Cell Transplantation (HSCT) is considered to be the only treatment providing long-term disease control for fit patients. The BRIDGE trial studied the safety and efficacy of a clofarabine-based salvage therapy prior to HSCT in patients with r/r AML. Here, we report the long-term follow up of this Phase II, multi-center, Intent-To-Transplant study and the impact of comorbidity on outcome. Eighty-four patients with a median age of 61 years (range 40 - 75) were enrolled. Patients were scheduled for at least one cycle of salvage therapy with CLARA (clofarabine 30 mg/m2 and cytarabine 1 g/m2, days 1-5). Chemo-responsive patients with a donor received HSCT after first CLARA. In the event of a prolonged donor search, HSCT was performed as soon as possible. The conditioning regimen consisted of clofarabine 30 mg/m2, day -6 to -3, and melphalan 140 mg/m2 on day -2. The ECOG score, hematopoietic cell transplantation-specific comorbidity index (HCT-CI) and Cumulative Illness Rating scale (CIRS) were obtained at study enrolment as well as prior to HSCT. Sixty-seven percent of the patients received HSCT within the trial. After a median follow up of 40months (95% CI, 38-49 months), the estimated 4-year OS (Figure 1) for all enrolled patients was 38% (95% CI, 28-50%) and Disease-Free Survival for transplanted patients was48% (95% CI, 36-64%). The CIR at four years was 30% (95% CI, 17-43%) and the NRM 22% (95% CI, 10-33%).Those patients who received an allogeneic HSCT within the trial had a median HCT-CI at the time of study enrollment of 1 (range, 0 - 6) compared to a median of 2 (range, 0 - 6) for those who did not proceed to allogeneic HSCT (p = .17). Corresponding figures for the CIRS were a median of 2 (range, 0 - 9) compared to 4 (range, 0 - 8) (p = .09). The median ECOG score was 1 (range, 0 - 3) in both groups. Compared to the time point of study enrollment, both the HCT-CI as well as the CIRS increased to a median of 2 (observed range of score, 0 - 7) and a median of 4 (observed range of score, 0 - 12), respectively, at the time of start of the conditioning regimen. This was almost exclusively due to an increase in infectious complications (Figure 2). Inmultivariate analysis, both the baseline HCT-CI and the ECOG score had a statistically significant impact with a HR of 1.22 (p = .025) and 1.72 (p = .001), respectively, on OS. Using a clofarabine-based salvage therapy combined with early allogeneic HSCT we were able to achieve good long-term results for patients with r/r AML. In this cohort, both the HCT-CI and the ECOG score gave prognostic information on OS, showing feasibility of comorbidity evaluation at the time of diagnose of r/r AML. Figure 1 OS of all enrolled patients Figure 1. OS of all enrolled patients Figure 2 Changes of the HCT-CI at baseline to HSCT Figure 2. Changes of the HCT-CI at baseline to HSCT Disclosures Middeke: Sanofi: Honoraria. Rösler:Janssen: Consultancy, Other: Travel/Accommodation/Expenses. Thiede:AgenDix: Employment, Other: Ownership. Schetelig:Sanofi: Honoraria.

Description: Background: In relapsed or refractory acute myeloid leukemia (AML), long-term disease-free survival may only be achieved with allogeneic hematopoietic stem cell transplantation (HSCT). Within the BRIDGE Trial, the safety and efficacy of a clofarabine salvage therapy as a bridge to HSCT was studied. Here, we report long-term survival data and the impact of donor availability at the time of study enrollment. The BRIDGE trial (NCT 01295307) was a phase II, multicenter, intent-to-transplant study. Patients and Methods: Between March 2011 and May 2013, 84 patients with relapsed or refractory AML older than 40 years were enrolled. Patients were scheduled for at least one cycle of induction therapy with CLARA (clofarabine 30 mg/m2 and cytarabine 1 g/m2, days 1-5). Patients with a donor received HSCT in aplasia after first CLARA. In case of a prolonged donor search, HSCT was performed as soon as possible. The conditioning regimen consisted of clofarabine 30 mg/m2, day -6 to -3, and melphalan 140 mg/m2 on day -2. In patients with partially matched unrelated donors, ATG (Genzyme) at a cumulative dose of 4.5 mg/kg was recommended. GvHD prophylaxis consisted of CsA and mycophenolate mofetil. Results: Forty-four patients suffered from relapsed AML and 40 patients had refractory disease. The median patient age was 61 years (range 40 – 75). According to the current ELN risk stratification 17% of pts were classified as favorable risk, 35% as intermediate I, 17% as intermediate II and 20% as adverse risk. The overall response rate assessed at day 15 after start of CLARA was 80% (defined as at least a marked reduction in BM blasts or BM cellularity and absence of blasts in the peripheral blood) with 31% of patients having less than 5% BM blasts at that time. Seventeen patients did not respond to CLARA, and were subsequently treated off-study. Due to early death, three patients were not evaluable for treatment response. Overall, 66% of the patients received HSCT within the trial. Donors were HLA-identical siblings in eight cases (14%), HLA-compatible unrelated donors in 30 cases (55%) and unrelated donors with one mismatch in 17 cases (31%). Treatment success was defined as complete remission (CR), CR with incomplete recovery (CRi) or CRchim (BM donor chimerism 〉95% and absolute neutrophil count 〉0.5/nL) on day 35 after HSCT. Treatment success was achieved in 61% of the patients. With a median follow up of 25 months, the OS for all enrolled patients at two years was 42% (95% CI, 32% to 54%). (Figure 1) The Leukemia-free survival at two years for those 51 patients who achieved the primary endpoint was 52% (95% CI, 40% to 69%). (Figure 2) At the time of enrollment, 14% of patients had a related donor and 33% had an unrelated donor available. In 46% of the patients, donor search was initiated at the time of enrollment. For 7% of patients, donor search was unsuccessful prior to enrollment and reinitiated. The OS at 2 years for patients with a related or an unrelated donor available was 75% (95% CI, 54% to 100%) and 47% (95% CI, 31% to 71%), respectively, while it was 29% (95% CI, 18% to 48%) for patients for whom donor search was initiated at time of enrollment (p = .09). Conclusions: Salvage therapy with CLARA, and subsequent conditioning with clofarabine and melphalan prior to allogeneic HSCT, provides good anti-leukemic activity in patients with relapsed or refractory AML. Fast unrelated donor search and work up, with conditioning in aplasia allowed a high rate of successful HSCTs. The leukemia-free survival for this group of elderly, high risk AML patients is very promising. Figure 1 Figure 1. Overall survival for all patients, n=84 Figure 2 Figure 2. Leukemia-free survival for all patients with primary treatment success, n=51 Disclosures Middeke: Genzyme: Speakers Bureau. Off Label Use: Clofarabine for AML. Schetelig:Genzyme: Research Funding; DKMS German Bone Marrow Donor Center: Employment.

Description: The pathophysiology of myelodysplastic syndrome (MDS) involves disturbed regulation of angiogenesis, apoptosis, proliferation and differentiation as well as immune surveillance. There is increasing evidence that rapamycin (sirolimus) might affect these pathways positively thus possibly being of therapeutic benefit in patients with this disease. These data prompted us to perform a phase I/II study to evaluate the safety and efficacy of rapamycin in the treatment of patients with MDS. Nineteen patients (median age 72 years) diagnosed with MDS according to the WHO classification received rapamycin orally with a target blood concentration of 3–12 ng/ml. Rapamycin was administered for a median of 3.7 months (range 0.3–11). Three patients (1 x RAEB-2, 1 x RAEB-1, 1 x RCMD) showed either a major (1 x platelet, 1 x neutrophil) or a minor (1 x erythroid, 2 x platelet) hematological response according to the IWG criteria. There was no statistically significant difference in the rapamycin plasma levels between the three responders (median plasma level 3.62, range 1.63–4.39) and non-responders (median plasma level 4.22, range 2.81–7.4). Major side effects were hyperlipidemia (n=4), stomatitis (n=3), thrombocytopenia (n=2) and urinary tract infection (n=1). Study medication had to be stopped due to side effects in five patients (26 %), one of them being a responder to rapamycin. Plasma levels of rapamycin were not elevated in patients experiencing toxicity. Taken together these data demonstrate that rapamycin might have biological activity in patients with rather advanced MDS. New and possibly less toxic analogues of rapamycin are currently developed. They could be candidates for future trials in patients with MDS.

Description: Purpose: The enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase and key epigenetic regulator involved in transcriptional repression and embryonic development. Loss of EZH2 activity by inactivating mutations is associated with poor prognosis in myeloid malignancies such as MDS. More recently, EZH2 inactivation was shown to induce chemoresistance in acute myeloid leukemia (AML) (Göllner et al., 2017). Data on the frequency and prognostic role of EZH2-mutations in AML are rare and mostly confined to smaller cohorts. To investigate the prevalence and prognostic impact of this alteration in more detail, we analyzed a large cohort of AML patients (n = 1604) for EZH2 mutations. Patients and Methods: All patients analyzed had newly diagnosed AML, were registered in clinical protocols of the Study Alliance Leukemia (SAL) (AML96, AML2003 or AML60+, SORAML) and had available material at diagnosis. Screening for EZH2 mutations and associated alterations was done using Next-Generation Sequencing (NGS) (TruSight Myeloid Sequencing Panel, Illumina) on an Illumina MiSeq-system using bone marrow or peripheral blood. Detection was conducted with a defined cut-off of 5% variant allele frequency (VAF). All samples below the predefined threshold were classified as EZH2 wild type (wt). Patient clinical characteristics and co-mutations were analyzed according to the mutational status. Furthermore, multivariate analysis was used to identify the impact of EZH2 mutations on outcome. Results: EZH2-mutations were found in 63 of 1604 (4%) patients, with a median VAF of 44% (range 6-97%; median coverage 3077x). Mutations were detected within several exons (2-6; 8-12; 14-20) with highest frequencies in exons 17 and 18 (29%). The majority of detected mutations (71% missense and 29% nonsense/frameshift) were single nucleotide variants (SNVs) (87%), followed by small indel mutations. Descriptive statistics of clinical parameters and associated co-mutations revealed significant differences between EZH2-mut and -wt patients. At diagnosis, patients with EZH2 mutations were significantly older (median age 59 yrs) than EZH2-wt patients (median 56 yrs; p=0.044). In addition, significantly fewer EZH2-mut patients (71%) were diagnosed with de novo AML compared to EZH2-wt patients (84%; p=0.036). Accordingly, EZH2-mut patients had a higher rate of secondary acute myeloid leukemia (sAML) (21%), evolving from prior MDS or after prior chemotherapy (tAML) (8%; p=0.036). Also, bone marrow (and blood) blast counts differed between the two groups (EZH2-mut patients had significantly lower BM and PB blast counts; p=0.013). In contrast, no differences were observed for WBC counts, karyotype, ECOG performance status and ELN-2017 risk category compared to EZH2-wt patients. Based on cytogenetics according to the 2017 ELN criteria, 35% of EZH2-mut patients were categorized with favorable risk, 28% had intermediate and 37% adverse risk. No association was seen with -7/7q-. In the group of EZH2-mut AML patients, significantly higher rates of co-mutations were detected in RUNX1 (25%), ASXL1 (22%) and NRAS (25%) compared to EZH2-wt patients (with 10%; 8% and 15%, respectively). Vice versa, concomitant mutations in NPM1 were (non-significantly) more common in EZH2-wt patients (33%) vs EZH2-mut patients (21%). For other frequently mutated genes in AML there was no major difference between EZH2-mut and -wt patients, e.g. FLT3ITD (13%), FLT3TKD (10%) and CEBPA (24%), as well as genes encoding epigenetic modifiers, namely, DNMT3A (21%), IDH1/2 (11/14%), and TET2 (21%). The correlation of EZH2 mutational status with clinical outcomes showed no effect of EZH2 mutations on the rate of complete remission (CR), relapse free survival (RFS) and overall survival (OS) (with a median OS of 18.4 and 17.1 months for EZH2-mut and -wt patients, respectively) in the univariate analyses. Likewise, the multivariate analysis with clinical variable such as age, cytogenetics and WBC using Cox proportional hazard regression, revealed that EZH2 mutations were not an independent risk factor for OS or RFS. Conclusion EZH mutations are recurrent alterations in patients with AML. The association with certain clinical factors and typical mutations such as RUNX1 and ASXL1 points to the fact that these mutations are associated with secondary AML. Our data do not indicate that EZH2 mutations represent an independent prognostic factor. Disclosures Middeke: Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees. Rollig:Bayer: Research Funding; Janssen: Research Funding. Scholl:Jazz Pharma: Membership on an entity's Board of Directors or advisory committees; Abbivie: Other: Travel support; Alexion: Other: Travel support; MDS: Other: Travel support; Novartis: Other: Travel support; Deutsche Krebshilfe: Research Funding; Carreras Foundation: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees. Hochhaus:Pfizer: Research Funding; Incyte: Research Funding; Novartis: Research Funding; Bristol-Myers Squibb: Research Funding; Takeda: Research Funding. Brümmendorf:Janssen: Consultancy; Takeda: Consultancy; Novartis: Consultancy, Research Funding; Merck: Consultancy; Pfizer: Consultancy, Research Funding. Burchert:AOP Orphan: Honoraria, Research Funding; Bayer: Research Funding; Pfizer: Honoraria; Bristol Myers Squibb: Honoraria, Research Funding; Novartis: Research Funding. Krause:Novartis: Research Funding. Hänel:Amgen: Honoraria; Roche: Honoraria; Takeda: Honoraria; Novartis: Honoraria. Platzbecker:Celgene: Research Funding. Mayer:Eisai: Research Funding; Novartis: Research Funding; Roche: Research Funding; Johnson & Johnson: Research Funding; Affimed: Research Funding. Serve:Bayer: Research Funding. Ehninger:Cellex Gesellschaft fuer Zellgewinnung mbH: Employment, Equity Ownership; Bayer: Research Funding; GEMoaB Monoclonals GmbH: Employment, Equity Ownership. Thiede:AgenDix: Other: Ownership; Novartis: Honoraria, Research Funding.