ALBERT

Description: Background: The StiL NHL1-2003 trial demonstrated that Bendamustine-Rituximab (B-R) is a highly effective treatment for patients with WM achieving a median PFS of 69.5 months. Rituximab (R) maintenance is part of a standard treatment for follicular lymphoma. In WM, however, the role of R maintenance is unclear. In this study we compared the effect of 2 years R maintenance vs. observation after first-line treatment with B-R in patients with previously untreated WM. Methods: Patients needed to have advanced stage of disease with indication for treatment (e.g. B-symptoms, anemia, hyperviscosity syndrome, etc.). Primary endpoint was progression free survival (PFS). Secondary endpoints included response rates, overall survival (OS), and toxicity. All patients were treated with up to 6 cycles of B-R plus 2 additional R cycles. Only patients responding to B-R were randomized to either R maintenance (q 2 months for 2 years) or observation. Results: Of 293 registered patients, 5 were excluded due to lack of data and other reasons. Median time of follow-up was 70.2 months at the time of this analysis (July 2019). 257 of 288 patients with a median age of 67 years were evaluable for response evaluation. The median baseline value of IgM was 31.3 g/l, and of Hb 10.1 g/dl. Median PFS for all patients (intention to treat) was 78.0 months. The median OS was not yet reached, with an estimated 5-year-survival of 78%. A total of 38 secondary malignancies were recorded, with 1 AML during observation and 1 MDS in R maintenance. 235 patients (91.4%) responded to B-R induction, with the majority of patients (231, 89.9%) achieving a partial remission. Of 218 randomized patients, 109 (50%) were randomized to R maintenance and 109 (50%) to observation. Median age of randomized patients was 67 years, patient characteristics were comparable for both groups. The 2-year R maintenance provided a better disease control with a median PFS of 101 months in the R maintenance group compared to the median PFS of 83 months in the observation group, however, this difference was not statistically significant with a hazard ratio of 0.80 (95% CI 0.51 - 1.25, p = 0.32). The median PFS of the group of all patients receiving treatment with B-R induction only was 65.3 months and is consistent with the results of the previous StiL NHL1-2003 trial (69.5 months). This group of 179 patients includes both non-randomized patients (B-R non-responder, not randomized for any reason) and patients randomized to observation. There was no difference in OS with the median not yet reached for both R maintenance and observation. Conclusions: We confirmed that induction with B-R is a highly effective treatment for WM. After a median observation time of 5.9 years the results could not demonstrate an improvement in PFS or OS after a 2-year R-maintenance when compared with observation after B-R induction in patients with WM. Disclosures Rummel: Sandoz: Honoraria; Janssen: Honoraria; Celgene: Honoraria; Roche Pharma AG: Honoraria, Research Funding. Hensel:Roche: Honoraria, Other: travel expenses. Buske:Hexal: Honoraria, Speakers Bureau; Roche: Honoraria, Research Funding, Speakers Bureau; Bayer: Research Funding; Janssen: Honoraria, Research Funding, Speakers Bureau; Pfizer: Honoraria; Celltrion: Honoraria, Speakers Bureau; Amgen: Research Funding. Schmidt:Janssen-Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: 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; Celgene: 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; Roche: Membership on an entity's Board of Directors or advisory committees; Hexal: Honoraria, Membership on an entity's Board of Directors or advisory committees; Biotest: Honoraria, 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; Daiichi-Sankyo: Honoraria, Membership on an entity's Board of Directors or advisory committees. Willenbacher:IQVIA: Membership on an entity's Board of Directors or advisory committees; oncotyrol: Employment, Research Funding; European Commission: Research Funding; Gilead Science: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sandoz: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Tirol Program: Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Honoraria; Sanofi: Membership on an entity's Board of Directors or advisory committees; Fujimoto: Consultancy, Honoraria; Myelom- und Lymphomselbsthilfe Österreich: Consultancy, Honoraria. Dürig:Celgene: Consultancy, Other: Travel or accommodations, Speakers Bureau; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support. Barth:Takeda: Honoraria; Lilly Pharma: Honoraria; Roche: Honoraria; Medac: Honoraria; Hexal: Honoraria. Hinke:Roche: Honoraria. Greil:Genentech: Honoraria, Research Funding; Eisai: Honoraria; Celgene: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Janssen-Cilag: Honoraria; Amgen: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; Ratiopharm: Research Funding; Boehringer Ingelheim: Honoraria; AstraZeneca: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; Novartis: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; MSD: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; Gilead: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; Pfizer: Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Mundipharma: Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Sandoz: Honoraria; Roche: Consultancy, Honoraria, Other: Travel/accomodation expenses, Research Funding; Sanofi Aventis: Honoraria; GSK: Research Funding; Daiichi Sankyo: Consultancy, Honoraria.

Description: A 75-year-old patient with slowly increasing polyneuropathy (PNP) (sensitive PNP, WHO°2), pre-existing for 6 months, in conjunction with a monoclonal gammopathy (IgG/kappa) is presented. Significant pre-existing conditions (for example, diabetes) do not exist. The physical examination findings and abdominal sonography are unremarkable. Serum values: M-gradient in the gamma fraction of the electrophoresis. IgG 11.58 g/L (standard 7.0 - 16.0) with decreased values for IgA 0.29 (standard 0.7-4.0) and IgM 0.21 (standard 0.4 to 2.3). Free light chains: kappa 152 mg/L (6.7 - 22.4), lambda 6.5 mg/l (8.3 - 27), kappa/lambda ratio: 23.49 (0.31 - 1.56). A bone marrow puncture showed 8% clonal plasma cells as well as an unremarkable set of female chromosomes. The FISH analysis of CD138+ enriched cells showed the following changes: - Vysis LSI ATM/CEP 11: 3 r + 2 gr (40/209) - MetaSystems XL DLEU/TP53: 1 r + 2 gr (31/231) - MetaSystems XL IGH plus: 1 F (r/gr) + 1 r + 1 gr (35/229) and 2 r + 1 gr (39/229) - MetaSystems XL t(11;14): 2 r + 3 gr (27/224) and 3 F (r/gr) + 1 r (88/224) - MetaSystems XL t(14;16): 2 r + 3 gr (57/232) and 2 F (r/gr) + 1 r + 1 gr (51/232) Consequently, FISH analysis found a deletion in the region 13q14 (DLEU) in 13.4% of the interphases, a balanced translocation t(14;16)(q32;q23) in 22.0% of the interphases and a balanced translocation t(11;14)(q13;q32) in 39.3% of the interphases, as well as an altered chromosome 14 from an unbalanced translocation t(11;14)(q13;q32). The unbalanced translocation results in a loss of chromosome material from 14q32-〉14qter and a gain in chromosome material from 11q13-〉11qter (confirmed by gain of ATM (11q22.3)). In addition, it was shown that the 13q14 deletion is associated with the translocation t(14;16)(q32;q23) and that the translocation t(11;14)(q13;q32) represents an independent cell clone. Computed tomography of the skeletal system showed isolated small osteolyses in the skullcap (the differential diagnosis could also be the physiologically occurring Pacchionian granulations), and osteoporosis of the spine. Clear CRAB criteria (hypercalcemia, renal failure, anemia, myeloma typical osteolytic lesions) are not available. Since PNP constitutes a treatment indication outside the CRAB criteria, it was recommended the patient start treatment to slow the progression of PNP. In principle, bortezomib belongs to the standard repertoire of first-line treatment in patients ineligible for high-dose therapy and stem cell transplantation (among other factors age 〉75 years). It is however problematic that an adverse effect of bortezomib is to induce PNP. Thalidomide, another effective preparation of the first-line treatment of elderly patients, is also rarely used due to this. In the last few months, the patient was recommended therapy with an approved combination of lenalidomide and dexamethasone as first-line therapy, and treatment has now started. Disclosures Hinrichsen: Center for Human Genetics and Laboratory Diagnostics (AHC) Dr. Klein, Dr. Rost and Colleagues: Employment. Klein:Zentrum für Humangenetik und Laboratoriumsdiagnostik Dr. Klein, Dr. Rost und Kollegen: Equity Ownership.

Description: Introduction: Myelodysplastic syndromes (MDS) are one of the most common haematological disorders of the older patient. Allogeneic stem cell stransplantation (ASCT) is the sole curative treatment. The number of eligible patients is limited due to age and comorbidities and only approximately one-third of these patients are cured by ASCT. Further therapeutic strategies such as hypomethylating agents (HMA) have often a short response duration. We recently found that ABT-199 effectively induces apoptosis in the leukemic progenitor compartment of higher-risk MDS and sAML patients, whereas healthy controls and low-risk patients remain unaffected (Jilg et al., 2016). These data suggest that pro-apoptotic ABT-199 might harbor potential as a novel treatment modality in higher-risk MDS patients. However, it remains unclear whether ABT-199 is a powerful option in patients after HMA failure. Synergistic effects of ABT-199 and 5-azacytidine (5-AZA) were also not analyzed in primary material of MDS/sAML patients yet. Here we investigate the effect of ABT-199 as single treatment and in combination with 5-azacytdine in bone marrow samples of 28 high-risk MDS/sAML patients under HMA therapy. We measured induction of apoptosis after ABT-199/5-azacytidine treatment and analyzed the effect on colony forming capacity. Methods: Purified bone marrow mononuclear cells (BMMNC) were treated with 1μM ABT-199 or a soluble control (DMSO) and/or 5-AZA (from 0.25µM to 10µM) for 72h in vitro. Apoptosis was analyzed by flow cytometry after staining for 7-AAD, Annexin V, and CD34 as a progenitor marker. The long-term survival was investigated by colony formation assay. Control samples were obtained from human femoral heads discarded after implantation of total endoprosthesis of the hip joint from hematologically healthy age-matched donors. Combination indices were calculated using ComboSyn. Results: 28 primary samples of patients under HMA treatment (complete response n=5; stable disease n=10 and primary failure n=13) were treated with either ABT-199 single and/or combination therapy with ABT-199 and 5-AZA. Combination therapy showed a clear synergistic effect with the most favorable combination index (CI=0.1446) at ABT-199 (1µM) and 5-AZA (1µM). As expected ABT-199 only showed reduced activity in patients with complete remission. However BCL-2 inhibition effectively decreased the number of viable CD34+ cells in patients with stable disease under HMA treatment. Patients with HMA have a very poor prognosis. As expected 5-AZA (1µM) had only slight effects on MDS stem/progenitor cells of these patients in the ex vivo setting. ABT-199 monotherapy was still able to effectively induce apoptosis in a 72h read-out. Combination therapy (ABT-199 and 5-AZA at a concentration of 1µM each) efficiently induced apoptosis in the CD34+stem/progenitor cells as well as in the bulk of BMMNCs. When compared with single treatment, we found that induction of apoptosis was significantly increased in the stem/progenitor population from patients with HMA failure after combination treatment (ABT-199 mono vs combination p= 0.0089 and 5-AZA mono vs. combination p=0.0006). Conclusion: To identify novel treatment options in higher-risk MDS/sAML patients, we analyzed the apoptotic effect of ABT-199 single and ABT-199/5-azacytidine in combination in primary samples of patients under 5-azacytidine treatment. ABT-199 and 5-azacytidine showed strong synergistic effects with the most favorable combination index with 5-azacytidine (1µM) and ABT-199 (1µM). Monotherapy with ABT-199 was able to induce cell death ex vivo in high-risk MDS/sAML evenafter HMA failure. Combination therapy induced apoptosis very effectively and significantly reduced colony forming capacity. Age-matched healthy controls were only marginally effected. We therefore conclude that combination of low-dose 5-azacytidine with ABT-199 is more effective than single treatment in this pre-treated cohort of high-risk MDS/sAML patients. Since patients with HMA failure have a very poor prognosis with limited treatment options combination therapy of ABT-199 and 5-azacytidine seems to be a promising therapy option. Disclosures No relevant conflicts of interest to declare.