Patnaik, Mrinal

AbstractThe current study was approached with the assumption that response to induction chemotherapy, in acute myeloid leukemia (AML), overshadows pre‐treatment risk variables in predicting survival and therefore be used as an anchor for a simplified risk model. We considered 759 intensively‐treated patients with AML, not promyelocytic: median age 60 years; primary 66%, secondary 25%, and therapy‐related 9%; European LeukemiaNet cytogenetic risk category favorable 8%, intermediate 61%, and adverse 31%. Complete remission with (CR) or without (CRi) count recovery was achieved in 608 (80%) patients. After a median follow‐up of 22 months, 503 deaths, 272 relapses, and 257 allogeneic hematopoietic stem cell transplants (AHSCTs) were recorded. Multivariable analysis identified failure to achieve CR/CRi (HR 3.8, 95% CI 3.1–4.8), adverse karyotype (2.2, 1.8–2.8), and age >55 years (2.1, 1.6–2.7) as main risk factors for survival. HR‐weighted scoring resulted in four‐tiered risk stratification: low (0 points; N = 183), intermediate‐1 (1 point; N = 331), intermediate‐2 (2 points; N = 117), and high (≥3 points; N = 128), with respective median survival (5‐year rate) not reached (68%), 34 (37%), 13 (20%), and 5 (5%) months (p < .001). FLT3‐ITD mutation was associated with inferior survival in intermediate‐1 (p = .004) and TP53 in intermediate‐2 (p = .06) and high (p = .02) risk disease; the latter was fully accounted for by the close association between TP53 mutation and complex/monosomal karyotype while the observations regarding FLT3‐ITD were not affected by treatment with midostaurin. AHSCT had a favorable impact on survival, most apparent in intermediate‐1 (p < .001), intermediate‐2 (p = .03), and high (p = .01) risk disease. The proposed 3‐factor survival model offers a novel prototype that is amenable to further enhancement by molecular information and was validated in an external cohort of 1032 intensively‐treated AML patients.

Abstract To determine the survival benefit of allogeneic hematopoietic cell transplantation (allo-HCT) in chronic myelomonocytic leukemias (CMML), we assembled a retrospective cohort of CMML patients 18-70 years old diagnosed between 2000 and 2014 from an international CMML dataset (n = 730) and the EBMT registry (n = 384). The prognostic impact of allo-HCT was analyzed through univariable and multivariable time-dependent models and with a multistate model, accounting for age, sex, CMML prognostic scoring system (low or intermediate-1 grouped as lower-risk, intermediate-2 or high as higher-risk) at diagnosis, and AML transformation. In univariable analysis, lower-risk CMMLs had a 5-year overall survival (OS) of 20% with allo-HCT vs 42% without allo-HCT (P &lt; .001). In higher-risk patients, 5-year OS was 27% with allo-HCT vs 15% without allo-HCT (P = .13). With multistate models, performing allo-HCT before AML transformation reduced OS in patients with lower-risk CMML, and a survival benefit was predicted for men with higher-risk CMML. In a multivariable analysis of lower-risk patients, performing allo-HCT before transformation to AML significantly increased the risk of death within 2 years of transplantation (hazard ratio [HR], 3.19; P &lt; .001), with no significant change in long-term survival beyond this time point (HR, 0.98; P = .92). In higher-risk patients, allo-HCT significantly increased the risk of death in the first 2 years after transplant (HR 1.46; P = .01) but not beyond (HR, 0.60; P = .09). Performing allo-HCT before AML transformation decreases life expectancy in lower-risk patients but may be considered in higher-risk patients.

AbstractTherapy‐related myeloid neoplasms (t‐MN) are aggressive malignancies in need of effective therapies. The BCL‐2 inhibitor venetoclax represents a paradigm shift in the treatment of acute myeloid leukemia. However, the effectiveness of venetoclax has not been studied in a large cohort of t‐MN. We retrospectively analyzed 378 t‐MN patients, of which 96 (25.4%, 47 therapy‐related acute myeloid leukemia, 1 therapy‐related chronic myelomonocytic leukemia, 48 therapy‐related myelodysplastic syndrome) received venetoclax. Median interval from t‐MN to venetoclax initiation was 2.9 (Interquartile range [IQR] 0.7–12) months, and patients received a median of 3 (IQR 1–4) cycles. The composite complete remission (CRc) rate, median progression‐free survival (PFS), and overall survival (OS) were 39.1%, 4.9 months, and 7 months, respectively. The upfront use of venetoclax and achieving CRc were associated with improved survival, whereas the presence of Chromosome 7 abnormalities was associated with an inferior survival. Neither the TP53‐status nor the percent bone marrow blast predicted the likelihood of CRc or survival. Paired genetic analysis performed at venetoclax initiation and failure did not show the evidence of the selection of the TP53‐mutated clone. In a propensity‐matched analysis, the use of venetoclax‐based regimen as the first‐line therapy was associated with a superior survival compared to hypomethylating agent (HMA)‐based first‐line therapy (9.4 vs. 6.1 months, p = .01). We conclude that the upfront use of venetoclax with HMA improved survival, though PFS and OS remain poor. As the phenotype at diagnosis or the percent blasts did not predict outcomes, venetoclax should be studied in all t‐MN phenotypes.

Clinical success with intravenous (IV) oncolytic virotherapy (OV) has to date been anecdotal. Here, we conducted a phase 1 clinical trial of systemic OV therapy and investigated the mechanisms of action in responding T-cell lymphoma (TCL) patients. A single IV dose of VSV-IFNβ-NIS was administered to patients with relapsed refractory hematologic malignancies to determine safety and efficacy across 4 dose levels (DL). Correlative studies were undertaken to evaluate viremia, virus shedding, virus replication and immune responses. Fifteen patients received VSV-IFNβ-NIS (7 multiple myeloma, 7 TCL, 1 acute myeloid leukemia); 3 patients were treated at each DL1 through DL3 (0.05, 0.17, and 0.5 x 1011 TCID50), and 6 at DL4 (1.7 x 1011 TCID50). There were no dose limiting toxicities. 3 of 7 patients with TCL had RECIST responses: a 3-month PR at DL2, a 6-month PR and a durable CR ongoing at 20 months at DL4. Viremia peaked at the end of infusion and no infectious virus shedding was detected. Plasma interferon-β levels, a biomarker of VSV-IFNβ-NIS replication, peaked between 4h and 48h post infusion. The patient with CR had robust viral replication with increased ell free DNA in her plasma, a very high peak IFNβ level of 18,213 pg/ml, a strong anti-VSV neutralizing antibody response, and increased numbers of tumor reactive T-cells. VSV-IFNβ-NIS as a single agent was effective in patients with TCL resulting in durable disease remissions in heavily pretreated patients. Correlative analyses suggest that responses may be due to a combination of direct oncolytic tumor destruction and immune-mediated tumor control. Further clinical testing is warranted. (This trial is registered at www.clinicaltrials.gov as NCT03017820).

AbstractErdheim–Chester disease (ECD) is a histiocytic neoplasm that predominantly harbors mitogen‐activated protein kinase (MAPK) pathway variants. MAPK inhibitors typically are effective treatments, but mutations outside the MAPK pathway, such as CSF1R variants, may cause refractory ECD. We describe a patient with a novel somatic mutation in CSF1R (CSF1RR549_E554delinsQ) that resulted in refractory ECD affecting the central nervous system. Cell model studies, RNA sequencing analysis, and in silico protein modeling suggested that she had a gain‐of‐function mutation occurring in a region critical for autoinhibition. The patient was treated with pexidartinib, a CSF1R inhibitor, and has had a complete clinical and metabolic response lasting more than 1.5 years to date. To our knowledge, this is the first report to describe successful treatment of a patient with ECD by using an agent that specifically targets CSF1R. This case also highlights the critical role of individualized molecular profiling to identify novel therapeutic targets in ECD.