ALBERT

Description: Immune checkpoint therapy has resulted in remarkable improvements in the outcome for certain cancers. To broaden the clinical impact of checkpoint targeting, we devised a strategy that couples targeting of the cytokine-inducible SH2-containing (CIS) protein, a key negative regulator of interleukin (IL)-15 signaling, with fourth generation 'armored' chimeric antigen receptor (CAR-IL-15) engineering of cord blood (CB) derived natural killer (NK) cells. This combined strategy boosted NK cell effector function through enhancing the Akt/mTORC1 axis and c-MYC signaling, resulting in increased aerobic glycolysis. When tested in a lymphoma mouse model, this combined approach improved NK cell anti-tumor activity more than either alteration alone, eradicating lymphoma xenografts without signs of any measurable toxicity. We conclude that targeting a cytokine checkpoint further enhances the antitumor activity of IL-15 secreting armored CAR-NK cells by promoting their metabolic fitness and anti-tumor activity. This combined approach represents a promising milestone in the development of the next generation of NK cells for cancer immunotherapy.

Description: Clonal diversity is a consequence of cancer cell evolution driven by Darwinian selection. Precise characterization of clonal architecture is essential to understand the evolutionary history of tumor development and its association with treatment resistance. Here, using a single-cell DNA sequencing, we report the clonal architecture and mutational histories of 123 acute myeloid leukemia (AML) patients. The single-cell data reveals cell-level mutation co-occurrence and enables reconstruction of mutational histories characterized by linear and branching patterns of clonal evolution, with the latter including convergent evolution. Through xenotransplantion, we show leukemia initiating capabilities of individual subclones evolving in parallel. Also, by simultaneous single-cell DNA and cell surface protein analysis, we illustrate both genetic and phenotypic evolution in AML. Lastly, single-cell analysis of longitudinal samples reveals underlying evolutionary process of therapeutic resistance. Together, these data unravel clonal diversity and evolution patterns of AML, and highlight their clinical relevance in the era of precision medicine.

Description: The optimal conditioning regimen for older patients with acute myeloid leukemia (AML) remains unclear. In this study, we compared outcomes of AML patients 〉60 years of age undergoing allogenic hematopoietic stem cell transplantation at our institution. All 404 consecutively treated patients received 1 of the following conditioning regimens: (1) fludarabine+melphalan 100 mg/m2 (FM100), (2) fludarabine+melphalan 140 mg/m2 (FM140), (3) fludarabine+IV busulfan AUC ≥ 5000/d × 4 d (Bu≥20000), and (4) fludarabine+IV busulfan AUC 4000/d × 4 d (Bu16000). A propensity score analysis (PSA) was used to compare outcomes between these 4 groups. Among the 4 conditioning regimens, the FM100 group had a significantly better long-term survival with 5-year progression-free survival of 49% vs 30%, 34%, and 23%, respectively. The benefit of the FM100 regimen resulted primarily from the lower nonrelapse mortality associated with this regimen, an effect more pronounced in patients with lower performance status. The PSA confirmed that FM100 was associated with better posttransplantation survival, whereas no significant differences were seen between the other regimen groups. In summary, older patients with AML benefited from a reduced-intensity conditioning regimen with lower melphalan doses (FM100), which was associated with better survival, even though it was primarily used in patients who could not receive a more intense conditioning regimen.

Description: A Correction to this paper has been published: https://doi.org/10.1038/s41467-020-19902-7

Description: Background: Although daunorubicin/cytarabine ("3+7")-based chemotherapy produces complete remission (CR) rates of 70% in younger adults, a significant proportion require re-induction to achieve CR or are refractory. Among those achieving CR, relapse after post-remission therapy is common and limits cure. Venetoclax (VEN) is an oral, selective BCL-2 inhibitor that promotes mitochondrial-mediated apoptosis in myeloblasts during cytotoxic stress. VEN plus hypomethylating agents in untreated unfit elderly AML patients (pts) elicits high response rates and improves overall survival. We hypothesize that VEN in combination with "3+7" could lead to a higher rate of measurable residual disease (MRD)-negative CR, perhaps obviating the need for reinduction as well as limiting relapse without undue toxicity. Methods: The primary objective of this phase 1 study was to determine the maximum tolerated dose (MTD) of VEN plus "3+7" induction and cytarabine-based consolidation therapy in previously untreated AML pts. Pt eligibility includes previously untreated AML,

Description: INTRODUCTION: NPM1 mutations (NPM1mut) occur in ∼30% of acute myeloid leukemia (AML) and frequently co-occur with mutations in other genes including those attributed to clonal hematopoiesis (CH) including DNMT3A and TET2, among others. CH mutations may persist beyond attaining NPM1mut-negative remission. Persistent CH may be associated with immunophenotypic alterations in myeloid progenitors detected by flow cytometry (FC) which poses an interpretive challenge in assessment of measurable residual disease (MRD) by FC. The aim of this study was to characterize the immunophenotypic alterations associated with persistent CH in the setting of NPM1mut clearance and to determine their possible clinical or biologic significance. METHODS: The cohort included 67 consecutive patients (pts) with NPM1mut AML treated at our institution between 01/2017 and 11/2019. FC assessment for MRD was performed an eight-color panel using FACSCanto II instruments (BD Biosciences, San Diego, CA) with a sensitivity of 10-3 to 10-4. Whole bone marrow (BM) DNA was interrogated for mutations with an 81-gene myeloid next-generation sequencing (NGS) panel using an Illumina MiSeq sequencer (Illumina, Inc., San Diego, CA, USA) with a sensitivity: 1% variant allelic frequency (VAF). RESULTS: Pts included 26 men and 41 women with a median age of 64 (range, 19-84) years with newly diagnosed NPM1mut AML. AML blasts had the following immunophenotype at baseline: promyelocytic-like phenotype (CD34-, CD117+, HLA-DR-) in 18 (27%), aberrant myeloid CD34-/CD117+/HLA-DR+ in 15 (22%), aberrant myeloid CD34+ in 13 (19%), myelomonocytic in 11 (16%), and monocytic in 10 (15%) cases. All pts had additional co-mutations at baseline (Fig 1). The most frequently co-mutated genes were DNMT3A (58%) FLT3 (51%), TET2 (27%), IDH2 (24%), PTPN11 (19%), IDH1 (18%), NRAS (16%), and SRSF2 (12%). Pts were treated with intensive (35;52%) and non-intensive induction regimens (32; 48%) (Fig 1); 22 (33%) received an allogeneic hematopoietic stem cell transplant as post-remission consolidation. We compared FC and NGS results in follow-up samples in pts achieving NPM1mut negative remission with adequate data available for comparison (n=50). 13 (26%) pts cleared all mutations whereas 37 (74%) had persistent CH. The most common mutations in the setting of residual CH involved DNMT3A (70%), TET2 (27%), IDH2 (19%) and IDH1 (11%). Among 37 pts with residual CH, 19 (51%) had no phenotypic alterations detected by FC while 17 (49%) had myeloid progenitors with alterations in intensity of antigen expression (increased CD13, CD123, CD117 and/or decreased CD38) or deviation from normal maturation but not diagnostic for AML MRD (herein referred to as pre-leukemic (PL) phenotype); 1 sample was MRD+ by FC. Mutation VAF of ≥5% was significantly more common (p=0.008) in cases with FC PL+ (100%) vs cases with normal FC phenotype (63%). IDH2 and SRSF2 mutation were exclusively observed in PL+CH+ cases with the former being statistically significant when compared with the FC-normal group (p=0.016). PL phenotype by FC did not correlate with intensity of induction therapy (41% treated with intensive regimens vs 59% non-intensive). The CH+/PL+ cohort had more pts ≥60 yrs old (67%) but the difference was not significant. There was no significant association between PL+ and residual mutation count. Presence of PL+ phenotype was not associated with a shorter relapse-free survival (RFS) (median not reached for both groups). CONCLUSIONS: Post-remission clonal hematopoiesis in the setting of NPM1mut clearance is common, and may result in immunophenotypic changes in myeloid progenitors, posing interpretive challenges for MRD assessment by FC. These alterations may be attributable to specific CH characteristics, such as IDH2 and SRSF2 mutations and VAF, but are not associated with a shorter RFS and thus should not be interpreted as residual AML or considered a high-risk attribute. Additional studies in other AML subtypes are warranted to further delineate these changes and their clinical significance. Figure 1 Disclosures DiNardo: Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Notable Labs: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; Takeda: Honoraria; Jazz: Honoraria; ImmuneOnc: Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; Syros: Honoraria; Agios: Consultancy, Honoraria, Research Funding; Calithera: Research Funding; MedImmune: Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Short:AstraZeneca: Consultancy; Takeda Oncology: Consultancy, Honoraria, Research Funding; Amgen: Honoraria; Astellas: Research Funding. Kadia:JAZZ: Honoraria, Research Funding; Ascentage: Research Funding; Astra Zeneca: Research Funding; Incyte: Research Funding; Celgene: Research Funding; Novartis: Honoraria; Cyclacel: Research Funding; Genentech: Honoraria, Research Funding; Amgen: Research Funding; Abbvie: Honoraria, Research Funding; Cellenkos: Research Funding; Pulmotec: Research Funding; Astellas: Research Funding; BMS: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding. Konopleva:Sanofi: Research Funding; Eli Lilly: Research Funding; AstraZeneca: Research Funding; Rafael Pharmaceutical: Research Funding; Amgen: Consultancy; F. Hoffmann La-Roche: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Stemline Therapeutics: Consultancy, Research Funding; Kisoji: Consultancy; Reata Pharmaceutical Inc.;: Patents & Royalties: patents and royalties with patent US 7,795,305 B2 on CDDO-compounds and combination therapies, licensed to Reata Pharmaceutical; Ascentage: Research Funding; Calithera: Research Funding; Forty-Seven: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; Cellectis: Research Funding; Agios: Research Funding; Ablynx: Research Funding. Kantarjian:Adaptive biotechnologies: Honoraria; Aptitute Health: Honoraria; BioAscend: Honoraria; Delta Fly: Honoraria; Janssen: Honoraria; Oxford Biomedical: Honoraria; Ascentage: Research Funding; Daiichi-Sankyo: Honoraria, Research Funding; BMS: Research Funding; Immunogen: Research Funding; Jazz: Research Funding; Novartis: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Sanofi: Research Funding; Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Research Funding; Amgen: Honoraria, Research Funding. Ravandi:Macrogenics: Research Funding; Celgene: Consultancy, Honoraria; AstraZeneca: Consultancy, Honoraria; Xencor: Consultancy, Honoraria, Research Funding; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Astellas: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Orsenix: Consultancy, Honoraria, Research Funding.

Description: Background: Blockade of PD-1/PD-L1 pathways enhances anti-leukemic responses in pre-clinical studies. PD1 inhibition alone had limited clinical activity in AML. CLTA4 inhibition demonstrated encouraging single-agent CR's in postASCT patients (pts), especially for extra-medullary (EMD) relapses (Davis M et al, NEJM 2016). AZA+Nivo up-regulated CTLA4 on bone marrow (BM) CD8 cells in both responders (R) and non-responders (NR) on treatment (Daver N, et al, Cancer Discovery 2019), suggesting a triplet of AZA+Nivo+Ipi may abrogate PD-1 mediated resistance. Methods: Pts were eligible for the AZA+Nivo (cohort 1, n=59) if they had R/R AML, ECOG ≤ 2, and adequate organ function. This cohort has completed enrollment. A cohort of AZA+Nivo+Ipi was opened (cohort 2), with the same eligibility criteria. Ipi 1mg/kg Q6 weeks was added to the established AZA+Nivo schedule and found to be safe in a lead-in dose cohort. Results: Cohort 1 (59 R/R AML) pts were treated with Aza+Nivo (Daver et al., Cancer Discovery 2019). CR/CRi and OS were superior to contemporary historic HMA-based clinical trial controls at MDACC (Table 1). Pts with low pretherapy BM blasts (

Description: Background: The TP53 gene is mutated in approximately half of human cancers and in up to 20% of acute myeloid leukemia (AML). TP53 mutations are associated with complex karyotype, high rates of resistance to standard treatment, and dismal outcome. However, new AML therapies are being developed that may potentially target these mutations (e.g. APR-246) or are largely ineffective in the context of mutated TP53 (e.g. MDM2 inhibitors). We sought to evaluate the frequency of treatment-emergent TP53 mutations in patients (pts) with TP53 wild type (WT) AML who relapsed or were refractory to therapy. Methods: This is a retrospective analysis of 1293 pts with WT TP53 AML who were treated at our institution with frontline therapy between December 2012 and March 2020. Pts with core binding factor (CBF) AML, those who did not have mutational data at baseline, or those in whom mutation profiling was not performed at relapse were excluded from the analysis. To identify TP53 mutations at baseline or relapse, a targeted next-generation sequencing (NGS) platform was performed. The analytical sensitivity of this NGS panel was established at 1-2% mutant reads in a background of WT reads. Mutations were manually reviewed to exclude any artifacts. Results: We identified 200 pts with non-CBF TP53 WT AML at diagnosis who relapsed after or were refractory to frontline therapy and are the subject of this analysis. Figure 1 shows the pt selection process. The baseline characteristics are shown in Table 1. At diagnosis, the median age was 69 years (range, 17-94 years). By ELN classification, 85 pts (43%) were adverse risk, 94 (47%) were intermediate risk, and 21 (11%) were favorable risk. Eighty-five pts (43%) were refractory to frontline therapy, and 115 (58%) relapsed after frontline therapy. Sixty-nine pts (35%) received intensive chemotherapy and 131 pts (66%) receiver low-intensity therapy. Overall, 29 pts (15%) developed a newly detectable TP53 mutation at some point over the course of therapy in the context of relapsed/refractory disease. Nineteen of these pts (66%) acquired a new detectable mutation after the first line of therapy, 6 pts (21%) after two lines of therapy, and 4 pts (14%) after three lines of therapy. Twenty-four pts (83%) acquired 1 TP53 mutation and 5 pts (17%) developed 2 TP53 mutations. The median variant allelic frequency (VAF) of the TP53 mutation was 15% (range 1.1% - 95.6%). Baseline factors associated with an increased likelihood of developing a new TP53 mutation included chromosome 5 abnormality (new TP53 mutation 40% vs. 12% in those without; P=0.02) and presence of an IDH2 mutation (28% vs. 12%, respectively; P=0.02). Development of a new TP53 mutation was more common after high-intensity therapy (23% vs. 10% after low-intensity therapy; P=0.02) and were also more common after hematopoietic stem cell transplant (HSCT) compared to those who did not undergo HSCT (36% vs. 12%, respectively; P=0.005). Thirteen (45%) of the new TP53 mutations occurred in the context of complex cytogenetics. Interestingly, in 7 of these cases, both the cytogenetic complexity and TP53 mutation emerged concomitantly and were not present at baseline. Among pts who developed new detectable TP53 mutations, the most common co-mutations were DDX41, DNMT3A, IDH2 and NRAS (each present in 15-20% of TP53-mutated cases). Seventeen (59%) of the 29 pts with new TP53 mutation responded to salvage therapy, and 7 underwent subsequent HSCT. Overall, survival was poor after development of newly detected TP53 mutation. The median overall survival (OS) after acquisition of TP53 mutation was 5.0 months, with a 1-year OS rate of 17% (Figure 2). Interestingly, we also identified a new detectable TP53 mutation in 5 pts (1%) out of the 555 pts who were in complete remission. The median VAF at the time of mutant TP53 acquisition was 2.5% (range 1.0% - 3.3%). With a median follow-up of 27 months since detection of the new TP53 mutation, none of these pts have developed hematologic relapse. Conclusion: We identified one or more newly detectable TP53 mutation(s) over the course of disease in 15% pts with relapsed/refractory AML. These mutations tended to be subclonal with a median VAF of 15%. New TP53 mutations were more common after intensive chemotherapy and/or HSCT. Our data suggest that these mutations may be acquired throughout the course of therapy, and therefore sequential monitoring may be relevant in the era of new potential TP53-targeting therapies. Disclosures Daver: Bristol-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Research Funding; Servier: Research Funding; Genentech: Research Funding; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novimmune: Research Funding; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Trovagene: Research Funding; Fate Therapeutics: Research Funding; ImmunoGen: Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Jazz: Consultancy, Membership on an entity's Board of Directors or advisory committees; Trillium: Consultancy, Membership on an entity's Board of Directors or advisory committees; Syndax: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy, Membership on an entity's Board of Directors or advisory committees; Daiichi Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Konopleva:Eli Lilly: Research Funding; Agios: Research Funding; Cellectis: Research Funding; Amgen: Consultancy; AbbVie: Consultancy, Research Funding; Rafael Pharmaceutical: Research Funding; Reata Pharmaceutical Inc.;: Patents & Royalties: patents and royalties with patent US 7,795,305 B2 on CDDO-compounds and combination therapies, licensed to Reata Pharmaceutical; Ablynx: Research Funding; Kisoji: Consultancy; AstraZeneca: Research Funding; Ascentage: Research Funding; Genentech: Consultancy, Research Funding; Calithera: Research Funding; Forty-Seven: Consultancy, Research Funding; F. Hoffmann La-Roche: Consultancy, Research Funding; Stemline Therapeutics: Consultancy, Research Funding; Sanofi: Research Funding. Ravandi:Celgene: Consultancy, Honoraria; Xencor: Consultancy, Honoraria, Research Funding; Orsenix: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Astellas: Consultancy, Honoraria, Research Funding; AstraZeneca: Consultancy, Honoraria; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding; Macrogenics: Research Funding; Amgen: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding. Kadia:Astellas: Research Funding; Abbvie: Honoraria, Research Funding; JAZZ: Honoraria, Research Funding; Amgen: Research Funding; Novartis: Honoraria; Incyte: Research Funding; Astra Zeneca: Research Funding; Pfizer: Honoraria, Research Funding; Cellenkos: Research Funding; Cyclacel: Research Funding; Ascentage: Research Funding; Celgene: Research Funding; BMS: Honoraria, Research Funding; Pulmotec: Research Funding; Genentech: Honoraria, Research Funding. DiNardo:MedImmune: Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; ImmuneOnc: Honoraria; Agios: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Calithera: Research Funding; Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Novartis: Consultancy; Notable Labs: Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria; Syros: Honoraria; Jazz: Honoraria. Issa:Celegene: Research Funding; Syndax: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees. Borthakur:Oncoceutics: Research Funding; BioLine Rx: Research Funding; Treadwell Therapeutics: Consultancy; Xbiotech USA: Research Funding; BMS: Research Funding; AstraZeneca: Research Funding; PTC Therapeutics: Research Funding; Incyte: Research Funding; Polaris: Research Funding; Jannsen: Research Funding; GSK: Research Funding; Novartis: Research Funding; Abbvie: Research Funding; Curio Science LLC: Consultancy; FTC Therapeutics: Consultancy; Argenx: Consultancy; PTC Therapeutics: Consultancy; BioLine Rx: Consultancy; BioTherix: Consultancy; Nkarta Therapeutics: Consultancy; Cyclacel: Research Funding. Yilmaz:Daicho Sankyo: Research Funding; Pfizer: Research Funding; Pint Pharma: Honoraria. Maiti:Celgene: Research Funding. Kantarjian:Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Cyclacel: Research Funding; Daiichi-Sankyo: Research Funding; Astex: Research Funding; Immunogen: Research Funding; Jazz Pharma: Research Funding; Pfizer: Honoraria, Research Funding; BMS: Research Funding; AbbVie: Honoraria, Research Funding; Takeda: Honoraria; Amgen: Honoraria, Research Funding; Ariad: Research Funding; Agios: Honoraria, Research Funding; Novartis: Research Funding. Short:AstraZeneca: Consultancy; Amgen: Honoraria; Astellas: Research Funding; Takeda Oncology: Consultancy, Honoraria, Research Funding.