Kurzfassung: Mutations of the isocitrate dehydrogenase-1 (IDH1) and IDH2 genes are among the most frequent alterations in acute myeloid leukemia (AML) and can be found in ∼20% of patients at diagnosis. Among 4930 patients (median age, 56 years; interquartile range, 45-66) with newly diagnosed, intensively treated AML, we identified IDH1 mutations in 423 (8.6%) and IDH2 mutations in 575 (11.7%). Overall, there were no differences in response rates or survival for patients with mutations in IDH1 or IDH2 compared with patients without mutated IDH1/2. However, distinct clinical and comutational phenotypes of the most common subtypes of IDH1/2 mutations could be associated with differences in outcome. IDH1-R132C was associated with increased age, lower white blood cell (WBC) count, less frequent comutation of NPM1 and FLT3 internal tandem mutation (ITD) as well as with lower rate of complete remission and a trend toward reduced overall survival (OS) compared with other IDH1 mutation variants and wild-type (WT) IDH1/2. In our analysis, IDH2-R172K was associated with significantly lower WBC count, more karyotype abnormalities, and less frequent comutations of NPM1 and/or FLT3-ITD. Among patients within the European LeukemiaNet 2017 intermediate- and adverse-risk groups, relapse-free survival and OS were significantly better for those with IDH2-R172K compared with WT IDH, providing evidence that AML with IDH2-R172K could be a distinct entity with a specific comutation pattern and favorable outcome. In summary, the presented data from a large cohort of patients with IDH1/2 mutated AML indicate novel and clinically relevant findings for the most common IDH mutation subtypes.

Kurzfassung: 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.

Kurzfassung: Background: Clinical superiority of R-MCP (rituximab, mitoxantrone, chlorambucil, prednisolone) vs. MCP alone in patients with advanced stage indolent Non-Hodgkin’s-Lymphoma was demonstrated in a prospective, randomized, controlled, multicenter clinical trial (n=358). Data on resource utilization were collected alongside this clinical trial. Objective: To evaluate the health economic consequences, i.e. total cost and cost-consequences, of R-MCP vs. MCP from the perspective of a German payer (statutory sickness fund). Methods: Resource utilization data on 329 patients were collected and analyzed for the treatment phase (8 month). In addition, an interim analysis of the first 3 years of the subsequent observation period (planned: 7 years) was conducted. Data on resource utilization for initial chemotherapy, chemotherapy administration, treatment of adverse events, treatment of complications/progressive disease, subsequent chemotherapies and treatment for other reasons were collected. Several sensitivity analyses were performed to address different cost environments (e.g. treatment at university hospital vs. municipal hospital vs. private practice) and discounting scenarios. Results: Mean cost of the treatment phase in the base case analysis was EUR 35,890 for R-MCP (95%CI: EUR 33,178 – 38,602 and EUR 21,508 MCP per patient (95%CI: EUR 17,703 – 25,314). More treatment cycles were administered in the R-MCP arm (1,026 MCP, 1,237 R-MCP). Mean cost per active treatment cycle was EUR 4,932 for R-MCP (95%CI: EUR 4,512 – 5,353) and EUR 3,270 for MCP (95%CI: EUR 2,619 – 3,922). Mean (undiscounted) cost per patient in the observation period amounted to EUR 9,973 for R-MCP (95%CI: EUR 6,015 – 13,931) and EUR 15,896 for MCP (95%CI: 13,407 – 18,385). Mean observation time, after end of active treatment, was similar in both arms, 28.5 months for R-MCP, 27.5 months for MCP. Costs for treatment of adverse events, new chemotherapies and other reasons were reduced by 23%–39%, cost for treatment of progressive disease by 76% in the R-MCP arm compared to MCP alone. Extrapolating data to a full 3-year observation period results in savings of EUR 8,214 per patient with R-MCP compared to MCP alone. This compensates approx. 60% of the higher costs from the treatment phase. Clinically, R-MCP resulted in an objective response rate of 85.6% vs. 65.5% with MCP. After two years, based on Kaplan Maier estimate, event free survival for R-MCP was 69% vs. 44% for MCP alone (p 〈 0.001) (For more detailed clinical results see abstract by Herold et al.) Conclusion: Initial treatment costs with R-MCP were EUR 14,382 higher compared to MCP alone. However, approx. 60% of additional costs are regained during the first three years after therapy due to savings for subsequent treatments, particularly for progressive disease. Combined with the clinical superiority of R-MCP, a favorable cost-effectiveness ratio may be expected when more mature data are available.

Kurzfassung: Introduction: The PETAL trial is a multicenter randomized controlled study for patients with aggressive lymphomas of diverse histologies (EudraCT 2006-001641-33, NCT00554164). In the study population as a whole interim PET (iPET) reliably predicted time to treatment failure (TTTF) and overall survival (OS). Interim PET-based treatment changes, however, had no impact on outcome (ASH 2014, abstract 391). Here we report the exploratory analysis for aggressive B cell lymphomas. Methods: Pts. aged 18 to 80 yrs. with newly diagnosed aggressive lymphomas and a positive baseline PET received 2 cycles of rituximab (R), cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) followed by iPET. The conditions of iPET were strictly defined: 3-week interval between the 2nd R-CHOP cycle and iPET to avoid inflammatory reactions (Eur J Nucl Med Mol Imaging 30:682, 2003), no G-CSF after the 2nd cycle to avoid altered glucose biodistribution (J Nucl Med 47:950, 2006), standardized uptake value (SUV)-based PET interpretation to improve reproducibility (favorable iPET response: reduction of maximum SUV by 〉 66 % compared to baseline; J Nucl Med 48:1626, 2007). Pts. with CD20+ lymphomas and a favorable iPET were randomized to receive 4 more cycles of R-CHOP or the same treatment plus 2 extra doses of R (part A of the trial). Pts. with an unfavorable iPET were randomized to continue R-CHOP for 6 additional cycles or receive 6 blocks of a more complex methotrexate-, cytarabine- and etoposide-based regimen originally designed for Burkitt lymphoma (Blood 124: 3870, 2014; part B). R was omitted in pts. with CD20- lymphomas. Sample size of the entire study population was based on the empirically derived assumption that treatment failure after 2 yrs. (TF: progression, relapse, treatment discontinuation due to toxicity, start of alternative therapy, death of any cause) could be improved from 80 % to 90 % in part A and from 30 % to 45 % in part B (alpha=0.05, power=0.8). Secondary endpoints included OS and toxicity. Results: Fifty-seven oncological centers and 23 nuclear medicine institutions participated in the trial. Between 2007 and 2012 1072 pts. were registered, and 862 (80.4 %) had a positive baseline PET, received 2 cycles R-CHOP, underwent iPET and were allocated to one of the post-iPET treatment arms detailed above. Reference pathology was available in 98 %, and median follow-up is 52 months. All in all, there were 779 patients with CD20+ aggressive B-cell lymphomas (90.4 % of all treated pts.) of whom 606 had diffuse large B-cell lymphoma (DLBCL), 42 primary mediastinal B-cell lymphoma (PMBCL) and 42 follicular lymphoma grade 3 (FL3). Interim PET was favorable in 691 pts. (88.7 %) and unfavorable in 88 pts. with CD20+ lymphomas (11.3 %). It was highly predictive of TTTF for CD20+ lymphomas in general and for each of the DLBCL, PMBCL and FL3 subgroups (Table). In CD20+ lymphomas and DLBCL, the iPET response predicted TF independently of the International Prognostic Index, and it was also predictive of OS. The groups of PMBCL and FL3 were too small for multivariate analyses. In part A, adding 2 extra doses of R failed to improve TTTF and OS in all histological entities. Separate analyses for subgroups defined by sex, age ( 〈 vs. 〉 60 yrs.) or a combination of the two showed no statistically significant benefit of extra doses of R in any of the subgroups. In pts. with an unfavorable iPET response, a switch from R-CHOP to the Burkitt regimen failed to improve TTTF or OS in CD20+ lymphomas in general (Figure) and in the DLBCL, PMBCL and FL3 subgroups. In part B, the Burkitt protocol was associated with more grade 3/4 leukopenia (82 % vs. 57 %, p=0.02), thrombocytopenia (59 % vs. 18 %, p=0.0001), infection (41 % vs. 16 %, p=0.017) and mucositis (39 % vs. 7 %, p=0.0007) than R-CHOP, but treatment-related mortality was similar in both arms (1 death each). Conclusion: In this large multicenter trial iPET proved highly predictive of outcome in pts. with CD20+ aggressive B-cell lymphomas, DLBCL, PMBCL or FL3 treated with R-CHOP. In pts. with a favorable iPET response, addition of 2 extra doses of R to 6 cycles R-CHOP failed to improve outcome in CD20+ lymphomas in general and in subgroups defined by histology, sex or age. In pts. with an unfavorable iPET response, switching to a more aggressive protocol also failed to improve outcome in any of the entities. Novel strategies are required for aggressive B-cell lymphomas failing to respond to the first 2 cycles of R-CHOP. Table Table. Figure Figure. Disclosures Duehrsen: Roche: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Alexion Pharmaceuticals: Honoraria, Research Funding. Giagounidis:Celgene Corporation: Consultancy. Grube:BMS, Sanofi: Consultancy. Klapper:Roche, Novartis, Amgen, Takeda: Research Funding. Hüttmann:Bristol-Myers Squibb, Takeda, Celgene, Roche: Honoraria; Gilead, Amgen: Other: Travel cost.

Kurzfassung: Background: Hodgkin’s and Reed-Sternberg cells are known to be resistant to apoptosis due to over-expression of Nuclear Factor kappa-B (NF-κB). Bortezomib increases intracellular levels of Inhibitor of Nuclear Factor kappa-B (I-κB) which inhibits activation of NF-κB. Laboratory studies indicate that bortezomib has a strong antiproliferative activity in Hodgkin’s lymphoma derived cell lines. We aimed to investigate the activity of bortezomib given in combination with dexamethasone in patients with relapsed Hodgkin’s lymphoma (HL). Methods: This was a multicenter, two-stage phase II study. Patients (pts.) with relapsed HL received 1.3 mg/m2 bortezomib plus 20 mg dexamethasone on days 1, 4, 8, and 11 of a 3-weekly cycle for up to 8 cycles. Response and toxicity were evaluated using standard criteria (Cheson 1999, Lister 1989; NCI-CTC v3.0). Circulating proteasome concentration was measured using sandwich enzyme-linked immunosorbent assay. Sample size was calculated according to Simon’s optimal design with 12 pts in the first stage and 25 thereafter. At least one response in the first 12 pts was required to proceed to the second stage. Results: As pre-specified in the protocol twelve pts were entered in the first stage and are assessable for response. All pts were heavily pre-treated with a median of 3 prior therapies and all but one had received high-dose chemotherapy. Two pts prematurely discontinued the study treatment due to toxicities after 2 and 3 cycles respectively. Both had stable disease at their final evaluation. All of the other 10 pts had progressive disease. Nine of these prematurely discontinued the study treatment due to insufficient response after a median of 2 cycles (range: 2–5 cycles) and only 1 received all 8 cycles. Since no response was observed in the first 12 pts, the study was stopped after the first stage. Eleven patients were assessable for toxicity as of August 2006. Two of these experienced no toxicity 〉 °I. The other 9 patients experienced at least 1 episode of a ≥ °II toxicity requiring some dose modifications, treatment delays, or discontinuation and 4 of these experienced °IV toxicity. Reported toxicities included thrombocytopenia (°II: 1 pat; °III: 1 pat; IV: 2 pat); lymphopenia (°III: 1 pat); febrile neutropenia (°IV: 1 pat); infection (°II: 2 pat); herpes zoster (°III: 1 pat); pain (°II: 2 pat); loss of appetite (°IV: 1 pat); cough (°III: 1 pat); epistaxis (°III: 1 pat); paralytic ileus (°IV: 1 pat); diarrhea (°III: 1 pat); and sleep disturbance (°III: 2 pat). Details on treatment administration and proteasome concentration will be presented as well as results of a meta-analysis of all available phase II studies of bortezomib in HL. Interpretation: Bortezomib in combination with dexamethasone is not active in heavily-pretreated patients with relapsed Hodgkin’s lymphoma. Furthermore, this treatment regimen possesses severe toxicities in heavily pre-treated Hodgkin’s patients. The use of bortezomib combined with dexamethasone is therefore discouraging in heavily pre-treated patients with HL. Further studies may only be justified with other combinations or less heavily pretreated patients.