Abstract: Axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) have both demonstrated impressive clinical activity in relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). In this study, we analyzed the outcome of 809 patients with R/R DLBCL after two or more previous lines of treatment who had a commercial chimeric antigen receptor (CAR) T cells order for axi-cel or tisa-cel and were registered in the retrospective French DESCAR-T registry study ( NCT04328298 ). After 1:1 propensity score matching ( n  = 418), the best overall response rate/complete response rate (ORR/CRR) was 80%/60% versus 66%/42% for patients treated with axi-cel compared to tisa-cel, respectively ( P   〈  0.001 for both ORR and CRR comparisons). After a median follow-up of 11.7 months, the 1-year progression-free survival was 46.6% for axi-cel and 33.2% for tisa-cel (hazard ratio (HR) = 0.61; 95% confidence interval (CI), 0.46–0.79; P  = 0.0003). Overall survival (OS) was also significantly improved after axi-cel infusion compared to after tisa-cel infusion (1-year OS 63.5% versus 48.8%; HR = 0.63; 95% CI, 0.45–0.88; P  = 0.0072). Similar findings were observed using the inverse probability of treatment weighting statistical approach. Grade 1–2 cytokine release syndrome was significantly more frequent with axi-cel than with tisa-cel, but no significant difference was observed for grade ≥3. Regarding immune effector cell-associated neurotoxicity syndrome (ICANS), both grade 1–2 and grade ≥3 ICANS were significantly more frequent with axi-cel than with tisa-cel. In conclusion, our matched comparison study supports a higher efficacy and also a higher toxicity of axi-cel compared to tisa-cel in the third or more treatment line for R/R DLBCL.

Abstract: Cytogenetically normal acute myeloid leukemias (CN-AML) represent about 50% of total adult AML. Despite the well-known prognosis role of gene mutations such as NPM1 mutations or FLT3 internal tandem duplication (FLT3-ITD), clinical outcomes remain heterogeneous in this subset of AML. Given the role of genomic instability in leukemogenesis, expression analysis of DNA repair genes might be relevant to sharpen prognosis evaluation in CN-AML. Publicly available gene expression profile dataset from two independent cohorts of patients with CN-AML were analyzed (GSE12417). A list set of 175 genes involved in six major DNA repair pathways (base excision repair (BER), NER, mismatch repair (MMR), homologous recombination repair (HRR), non-homologous end joining (NHEJ) and FANC pathways) was defined using the REPAIRtoire database (http://repairtoire. genesilico.pl) and review of the literature. We investigated the prognostic value of these 175 genes involved in DNA repair. Among these genes, 23 were associated with a prognostic value, using the MaxStat R function. To further corroborate gene expression data on a functional level, CRISPR or RNAi screening publicly available data were used (Dependency Map data, Broad Institute, www.depmap.org). Among the 19 genes associated with a poor outcome, APEX (BER), RTEL1 (HRR) and COPS6 (NER) were identified as significant essential AML genes (p = 7.9e-05, 3.4e-04 and 2.8e-04 respectively). The prognostic information provided by these 23 genes was summed (sum of the beta coefficients of the Cox model for each prognostic gene, weighted by +1 or -1 according to the patient signal ≥ the probe set MaxStat value) in a DNA repair score to consider connection of DNA repair pathways. In the CN-AML training cohort (n=162), DNA repair score allowed to define a group of patients (n=87; 53,7%) with poor median overall survival (OS) of 233 days (95% CI: 184-260). These results were confirmed in the validation cohort (n=78) (median OS: 120 days; 95% CI: 36-303). In multivariate Cox analysis, the DNA repair score, NPM1and FLT3-ITD mutational status remained independent prognosis factors in CN-AML. Therefore, we investigated the interest of combining DNA repair score and NPM1/FLT3 mutational status to predict CN-AML outcome. Patients were classified according to prognosis value of DNA repair score (0 point for group I; 1 for group II; 2 for group III), and NPM1/FLT3 mutational status (0 point if NPM1 mutation without FLT3-ITD; 2 points if FLT3-ITD without NPM1 mutation; 1 point in other situations). The sum of the prognostic information was computed for all patients, allowing to separate patients in three new prognostic groups: group A including patients with 0 or 1 point, group B for patients with 2 points and group C for patients with 3 or 4 points. Combining these parameters allowed the identification of three risk groups with different clinical outcomes in both training and validation cohorts (Figure 1). In the training cohort, median OS was not reached (95% CI: NR-NR), 326 days (95% CI: 127-NR) and 236 days (95% CI: 190-263) respectively for patients in groups A, B and C. One-year OS was 90.3% (95% CI: 80.5-100) in group A, 49.3% (95% CI: 37.1-65.7) in group B, and 24.2% (95% CI: 16.2-36.2) in group C.These results were confirmed in the validation cohort where median OS was not reached (95% CI: 1278-NR), 516 days (95% CI: 308-NR) and 253 days (95% CI: 52-403) for patients respectively in groups A, B and C. One-year OS was 92.6% (95% CI: 83.2-100) in group A, 54.9% (95% CI: 39.8-75.7) in group B, and 26.5% (95% CI: 12.4-55.8) in group C. OS was statistically different between groups A, B and C in both training and validation cohorts. Combined with NPM1 and FLT3 mutational status, our GE-based DNA repair score might be used as a biomarker to predict outcomes for patients with CN-AML. DNA repair score has the potential to identify CN-AML patients whose tumor cells are dependent on specific DNA repair pathways to design new therapeutic avenues. Disclosures Cartron: Celgene: Consultancy, Honoraria; F. Hoffmann-La Roche: Consultancy, Honoraria; Sanofi: Honoraria; Gilead: Honoraria; Jansen: Honoraria; Abbvie: Honoraria. Moreaux:Diag2Tec: Consultancy.

Abstract: Resistance to chemotherapeutic drugs is a major cause of treatment failure in acute myeloid leukemias (AML). To better characterize the mechanisms of chemoresistance, we first identified genes whose expression is dysregulated in AML cells resistant to daunorubicin or cytarabine, the main drugs used for induction therapy. The genes found to be activated are mostly linked to immune signaling and inflammation. Among them, we identified a strong upregulation of the NOX2 NAPDH oxidase subunit genes (CYBB, CYBA, NCF1, NCF2, NCF4 and RAC2). The ensuing increase in NADPH oxidase expression and production of reactive oxygen species, which is particularly strong in daunorubicin-resistant cells, participates in the acquisition and/or maintenance of resistance to daunorubicin. Gp91phox (CYBB-encoded Nox2 catalytic subunit), was found to be more expressed and active in leukemic cells from patients with the French-American-British (FAB) M4/M5 subtypes of AML than in those from patients with the FAB M0-M2 ones. Moreover, its expression was increased at the surface of patients’ chemotherapy-resistant AML cells. Finally, using a gene expression based score we demonstrated that high expression of NOX2 subunit genes is a marker of adverse prognosis in AML patients. The prognostic NOX score we defined is independent of the cytogenetic-based risk classification, FAB subtype, FLT3/NPM1 mutational status and age.

Abstract: Genotoxicants have been used for decades as front-line therapies against cancer on the basis of their DNA-damaging actions. However, some of their non-DNA-damaging effects are also instrumental for killing dividing cells. We report here that the anthracycline Daunorubicin (DNR), one of the main drugs used to treat Acute Myeloid Leukemia (AML), induces rapid (3 h) and broad transcriptional changes in AML cells. The regulated genes are particularly enriched in genes controlling cell proliferation and death, as well as inflammation and immunity. These transcriptional changes are preceded by DNR-dependent deSUMOylation of chromatin proteins, in particular at active promoters and enhancers. Surprisingly, inhibition of SUMOylation with ML-792 (SUMO E1 inhibitor), dampens DNR-induced transcriptional reprogramming. Quantitative proteomics shows that the proteins deSUMOylated in response to DNR are mostly transcription factors, transcriptional co-regulators and chromatin organizers. Among them, the CCCTC-binding factor CTCF is highly enriched at SUMO-binding sites found in cis-regulatory regions. This is notably the case at the promoter of the DNR-induced NFKB2 gene. DNR leads to a reconfiguration of chromatin loops engaging CTCF- and SUMO-bound NFKB2 promoter with a distal cis-regulatory region and inhibition of SUMOylation with ML-792 prevents these changes.

Abstract: Background : AETHERA randomized controlled study (Moskowitz, Lancet 2015) showed that the administration of Brentuximab Vedotin (BV) maintenance after autologous stem cell transplantation (ASCT) improved progression free survival (PFS) in BV-naive refractory/relapsed (R/R) Hodgkin lymphoma (HL) patients. However, since BV approval for R/R HL in 2012, many patients are receiving salvage BV before ASCT, alone or combined with chemotherapy. In the AMAHRELIS retrospective nationwide French study, we investigated the real-life outcome of patients with R/R HL mostly treated with BV-based salvage therapies and who received post-ASCT BV maintenance. Objectives : As primary 0objective, we assessed 2 years-PFS of patients treated with post-ASCT BV maintenance from 2012 to 2017 in France. As secondary objectives, we correlated variables (such as use of salvage BV before ASCT, centrally reviewed TEP-assessed response) with survival, and evaluated reported tolerance of BV using the CTCAE v4.0 criteria. Methods : We conducted this observational retrospective study in 58 national centers. Inclusion criteria were R/R HL patients who received at least two infusions of BV after ASCT, at the exclusion of patients in progression after transplant. Among 1134 patients who underwent ASCT for R/R HL between 2012 and 2017 in France based on the French society of bone marrow transplantation database, 835 (74%) patients were screened and data were available for 794 (70%) patients. FDG-PET scan at relapse and before transplantation were recorded and centrally reviewed (still ongoing). FDG-PET scan were reported using the Deauville score (DS), and complete remission was defined by a DS & lt; 4. Post-transplant status was evaluated based on CT-scan or on FDG-PET scan results. This study was approved by the SFGMTC and the LYSA. Results : Fifteen percent (115/794) of patients met eligibility criteria, and were enrolled in this study. Among them, 95% met inclusion criteria for BV maintenance according to the AETHERA study as primary refractory disease (43%), early relapse (27%) or extranodal disease (49%). The mean number of BV injections after ASCT was 11 (3-18). Patients characteristics were : mean age was 34 y (range between 16-70y), 54% were male, and 57% of patients were stage III or IV at relapse. Notably, 70% of patients received BV as salvage therapy and 81% achieved a complete remission before ASCT. The median follow-up period was 35 months. The 2 years survival for the whole cohort was 75,3% for PFS (95% CI : 68,4-84,3) and 96,4% for overall survival (95% CI : 94,2-100) (Figure 1). The use of BV as part of salvage therapy before transplant had no impact on PFS. We observed a trend to an increased occurrence of neuropathy in patients receiving BV before transplant without impact on early treatment discontinuation. We tested several variables for correlation with survival using a univariate Cox model including high risk patients defined as primary refractory disease or early relapse and disseminated disease, extranodal relapse, use of BV before transplant, number of salvage lines, remission status before and after transplant (complete response versus partial response or stable disease), time between ASCT and BV onset and number of BV cycles after transplant. Among these variables, high risk status, less than 10 post transplant BV cycles and absence of post transplant complete remission significantly correlated with a reduced survival probability, and remained significant after analysis using a multivariate Cox model (Table 1). Conclusion : From the real-life AMAHRELIS study, we confirmed the very good outcome of R/R HL patients in the era of post-transplant BV maintenance, with a 2y-PFS of 75% similar to the results of the AETHERA landmark study (2y-PFS of 63%). The results of current strategies with pre- and post-transplant BV outperformed historical series based on high dose therapies, including those of tandem transplant for high risk patients. Future studies incorporating BV strategies with immune checkpoint inhibitors might improve outcome in R/R HL patients. Disclosures Meignan: ROCHE: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company). Sibon:takeda france: Consultancy. Stamatoulas Bastard:Pfizer: Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Celgene: Honoraria; Takeda: Consultancy. Fornecker:Takeda: Consultancy; Roche: Consultancy. Casasnovas:Takeda: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding; Roche: Consultancy, Honoraria, Other: travel, accomodations, expenses, Research Funding; Gilead: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding; Abbvie: Consultancy, Honoraria; MSD: Consultancy, Honoraria; Amgen: Consultancy, Honoraria. Cartron:Gilead: Honoraria; Jansen: Honoraria; Abbvie: Honoraria; Celgene: Consultancy, Honoraria; Sanofi: Honoraria; F. Hoffmann-La Roche: Consultancy, Honoraria. Ghesquieres:Gilead: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; CELGENE: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Roche: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Janssen: Honoraria. Brice:Takeda: Consultancy; Roche: Consultancy. Hermine:AB Science: Consultancy, Current equity holder in publicly-traded company, Honoraria, Patents & Royalties, Research Funding; Celgene BMS: Consultancy, Research Funding; Roche: Consultancy; Novartis: Research Funding; Alexion: Research Funding. Rubio:Medac: Consultancy; Gilead: Honoraria; MSD: Honoraria; Novartis: Honoraria; Neovii: Research Funding. Deau Fischer:Takeda: Consultancy; Roche: Consultancy.

Abstract: Acute Myeloid Leukemias (AML) are severe hematomalignancies with dismal prognosis. The post-translational modification SUMOylation plays key roles in leukemogenesis and AML response to therapies. Here, we show that TAK-981 (subasumstat), a first-in-class SUMOylation inhibitor, is endowed with potent anti-leukemic activity in various preclinical models of AML. TAK-981 targets AML cell lines and patient blast cells in vitro and in vivo in xenografted mice with minimal toxicity on normal hematopoietic cells. Moreover, it synergizes with 5-azacitidine (AZA), a DNA-hypomethylating agent now used in combination with the BCL-2 inhibitor venetoclax to treat AML patients unfit for standard chemotherapies. Interestingly, TAK-981+AZA combination shows higher anti-leukemic activity than AZA+venetoclax combination both in vitro and in vivo, at least in the models tested. Mechanistically, TAK-981 potentiates the transcriptional reprogramming induced by AZA, promoting apoptosis, alteration of the cell cycle and differentiation of the leukemic cells. In addition, TAK-981+AZA treatment induces many genes linked to inflammation and immune response pathways. In particular, this leads to the secretion of type I interferon (IFN-I) by AML cells. Finally, TAK-981+AZA induces the expression of Natural Killer (NK)-activating ligands (MICA/B) and adhesion proteins (ICAM-1) at the surface of AML cells. Consistently, TAK-981+AZA-treated AML cells activate NKs and increase their cytotoxic activity. Targeting SUMOylation with TAK-981 may thus be a promising strategy to both sensitize AML cells to AZA and reduce their immune-escape capacities.

Abstract: Differentiation therapies using all-trans retinoic acid (ATRA) are highly efficient at treating acute promyelocytic leukemia (APL), a subtype of acute myeloid leukemia (AML). However, their efficacy, if any, is limited in the case of non-APL AML. We report here that inhibition of SUMOylation, a posttranslational modification related to ubiquitination, restores the prodifferentiation and antiproliferative activities of retinoids in non-APL AML. Controlled inhibition of SUMOylation with the pharmacologic inhibitors 2-D08 or anacardic acid, or via overexpression of SENP deSUMOylases, enhanced the ATRA-induced expression of key genes involved in differentiation, proliferation, and apoptosis in non-APL AML cells. This activated ATRA-induced terminal myeloid differentiation and reduced cell proliferation and viability, including in AML cells resistant to chemotherapeutic drugs. Conversely, enhancement of SUMOylation via overexpression of the SUMO-conjugating enzyme Ubc9 dampened expression of ATRA-responsive genes and prevented differentiation. Thus, inhibition of the SUMO pathway is a promising strategy to sensitize patients with non-APL AML to retinoids and improve the treatment of this poor-prognosis cancer. Significance: SUMOylation silences key ATRA-responsive genes in nonpromyelocytic acute myeloid leukemias. Cancer Res; 78(10); 2601–13. ©2018 AACR.