Daver, Naval

Abstract Background: SGI-110 is a second generation HMA formulated as a dinucleotide of decitabine (DAC) and deoxyguanosine delivered as a small volume SC injection that yields longer half-life and more extended DAC exposure than DAC IV infusion. A phase 1 clinical trial of SGI-110 demonstrated a differentiated pharmacokinetic profile from DAC IV, potent hypomethylation, and clinical responses in previously treated patients with MDS and AML (Kantarjian et al. 2012). Phase 1 established 60 mg/m2 QDx5 as the biologically effective dose (BED), and 90 mg/m2QDx5 as the Maximum tolerated dose (MTD) in MDS patients given in 28-day cycles. Phase 2 is conducted to evaluate dose response between the BED and MTD in MDS patients. Methods: Int, or HR MDS, and CMML patients who were either treatment-naïve or previously treated were randomized to either 60 mg/m2 or 90 mg/m2QDx5 every 28 days. Efficacy was evaluated by the clinical responses of CR, PR, marrow CR (mCR), and Hematological Improvement (HI) based on the International Working Group Criteria 2006 as well as transfusion-independence. Adverse events (AEs) as graded by the CTCAE v4 criteria and pharmacodynamic biological activity as measured by Long Interspersed Nucleotide Element LINE-1 (an index of global DNA methylation) were also assessed. Patients are being followed for overall survival. Results: The study completed target enrolment with 102 patients: 53 who were refractory or have relapsed on prior treatment, and 49 previously untreated. Fifty three patients were randomized to 60 mg/m2 and 49 patients to 90 mg/m2 QDx5 with a median follow up of 8.2 months (range 1-21). Most baseline patient characteristics were well balanced between the 2 treatment arms with no significant differences in median age (71.7 vs. 72.5 y); male gender (70 vs. 61%); ECOG PS 2 (15 vs. 12%); HR MDS (28 vs. 37%); transfusion-dependence (57 vs. 55%), median baseline Hb (9.25 vs. 9.3 g/dL); platelets count (42.5 vs. 45 x109/L), and neutrophils count (1.19 vs. 1.16 x109/L) for the 60 and 90 mg/m2 QDx5 respectively. However, there were 15 CMML patients (28%) randomized to 60 mg/m2 vs. only 7 CMML patients (14%) randomized to 90 mg/m2(p=0.097). All but 2 patients in the previously treated group received one or more HMA. At the time of the data cutoff, 38 of 102 patients (37%) were still on treatment. Median number of treatment cycles was 4 for previously treated patients, and 5 for the treatment naïve group (range 1-22 cycles). CR+mCR were observed in 10/53 (19%), and 11/49 (22%) in the 60 and 90 mg/m2 arms respectively (p=0.8). CR was observed in 7/49 treatment naïve patients (14%) while CR+mCR were observed in 11/53 previously treated patients (21%) with no significant differences between 60 and 90 mg/m2 arms. Transfusion independence for at least 8 weeks was reported in 32% and 24% for platelets and RBCs respectively with no difference between the 2 treatment arms. Treatment naïve patients benefited from higher rate of transfusion-independence (58% and 46% for platelets and RBCs respectively). Potent demethylation was achieved in both treatment arms with a mean LINE-1 DNA demethylation of 27.3 and 30.5% for 60 and 90 mg/m2 respectively (p=0.12). Overall incidence of Grade ≥3 AEs regardless of relationship to treatment was reported in 81 vs. 88% for 60 and 90 mg/m2 treatment arms respectively (p=0.42).There was a slightly higher but non-significant difference in Grade ≥3 thrombocytopenia (51 vs 38%) and pneumonia (20 vs. 13%) for the 90 mg/m2 arm compared to 60 mg/m2. Early 8-week any-cause mortality occurred in 3/102 patients treated (3%), 2 at 60 and 1 at 90 mg/m2. Follow up for survival is still ongoing. Conclusions: SC SGI-110 is a well-tolerated novel HMA with biological and clinical activity in the treatment of Int and HR MDS, and CMML patients with particularly promising activity in patients previously treated with azacitidine or decitabine. Clinical responses, transfusion independence, DNA demethylation as assessed by LINE-1, and Safety did not significantly differ between the 2 treatment doses. Disclosures Tibes: Astex Pharmaceuticals, Inc.: Research Funding. Rosenblat:Astex Pharmaceuticals, Inc.: Research Funding. Yee:Astex Pharmaceuticals, Inc.: Research Funding. Griffiths:Astex Pharmaceuticals, Inc.: Research Funding. Issa:Astex Pharmaceuticals, Inc.: Consultancy, Research Funding. Naim:Astex Pharmaceuticals, Inc.: Employment. Taverna:Astex Pharmaceuticals, Inc.: Employment. Hao:Astex Pharmaceuticals, Inc.: Employment. Azab:Astex Pharmaceuticals, Inc.: Employment. Roboz:Astex Pharmaceuticals, Inc.: Consultancy.

e18521 Background: The FDA-approved drug trabectedin is a DNA minor groove binder (MGB) with activity against translocation-associated sarcomas. Lurbinectedin is a next-generation MGB, with activity against myeloid leukemia cells. A phase I clinical trial was initiated to determine recommended doses in MDS/AML. Further assessment of its safety, tolerability, and pharmacogenetics were studied. Methods: In total, 42 patients with relapsed/refractory MDS/AML received lurbinectedin, using a 3+3 study design. It was administered as a 1-hour IV infusion first at 3.5, 5, 6, and 7mg per dose on days 1 and 8. Subsequently, it was administered on days 1, 2, and 3, using 1, 1.5, 2, or 3mg per dose per patient. Results: Three patients had dose-limiting toxicities (DLTs), which were rhabdomyolysis (up to gr 4), hyperbilirubinemia (gr 3), and oral herpes (gr 3). All DLTs occurred in the 6 and 7mg cohorts. Adverse events included febrile neutropenia/infections (n = 3), GI (n = 6) and pulmonary (n = 2) toxicity, hyperhidrosis (n = 1), and QT prolongation (n = 1). Overall, 33 of 42 patients (79%) had reduction of blasts in peripheral blood (PB) or bone marrow (BM) at nadir, including 23 (55%) with > 50% reduction in PB blasts alone (n = 18) or both BM and PB blasts (n = 5). One patient had PR, 2 patients had morphologic leukemia-free survival, and most (n = 30) were discontinued for progressive disease. Early deaths occurred from disease-related causes, not attributable to lurbinectedin. Thirty-two patients treated at MD Anderson were analyzed for clinical characteristics and responses. Notably, among patients with follow-up bone marrow biopsy, those with a cytogenetic abnormality at chromosome 11q21-23 had significantly greater bone marrow blast reduction than those without such abnormality (change in percentage blasts: -31±14% [n = 4] vs. 8±8% [n = 16], respectively; P= 0.04). Conclusions: Lurbinectedin is generally safe and tolerated at dose levels tested. While no sustained remissions > 3 cycles were observed in these highest-risk patients, single-agent lurbinectedin was transiently leukemia suppressive for some patients, including some with abnormal chr11q or TP53 mutation. Rational combinations and situational uses of lurbinectedin are under consideration. Clinical trial information: NCT01314599.

AbstractTrabectedin is an FDA‐approved DNA minor groove binder that has activity against translocation‐associated sarcomas. Lurbinectedin is a next‐generation minor groove binder with preclinical activity against myeloid leukemia cells. A dose‐finding phase 1 clinical trial was performed in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) with further assessment of safety and tolerability. Forty‐two patients with relapsed/refractory AML/MDS received lurbinectedin administered as a 1‐hour intravenous infusion in a 3 + 3 study design. Two dosing schedules were used: 3.5, 5, 7, or 6 mg on days 1 and 8 or 2, 3, 1, or 1.5 mg for 3 consecutive days on days 1 to 3. Three patients experienced dose‐limiting toxicities of rhabdomyolysis (grade 4), hyperbilirubinemia (grade 3), and oral herpes (grade 3) with the day 1 and 8 schedule. Otherwise, adverse events mainly consisted of gastrointestinal manifestations (n = 11), febrile neutropenia/infections (n = 4), pulmonary toxicity (n = 2), and renal failure (n = 2). The most common laboratory abnormalities observed were an increase in creatinine (93%) and anemia, neutropenia, and thrombocytopenia (100%). Overall, 33 of 42 patients (79%) had reduction in blasts in peripheral blood or bone marrow. One patient achieved a partial response and 2 patients a morphologic leukemia‐free state. Most (n = 30, 71%) were discontinued due to progressive disease. Early deaths occurred from disease‐related causes that were not attributable to lurbinectedin. Four patients with a chromosome 11q21‐23 abnormality had significantly greater bone marrow blast reduction than those without such abnormality, with decrease of 31 ± 14% (n = 4) vs 8 ± 8% (n = 16), respectively (P = .04). Overall, lurbinectedin was safe and tolerated using the schedules and dose levels tested. While no sustained remissions were observed, single‐agent lurbinectedin was transiently leukemia suppressive for some patients.

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of severe immune activation and dysregulation resulting in extreme and often life‐threatening inflammation. HLH has been well recognized in pediatric populations, and most current diagnostic and therapeutic guidelines are based on pediatric HLH. Recently there has been recognition of HLH in adults, especially secondary to immune deregulation by an underlying rheumatologic, infectious, or malignant condition. This review is focused on malignancy‐associated HLH (M‐HLH), in which possible mechanisms of pathogenesis include severe inflammation, persistent antigen stimulation by the tumor cells, and loss of immune homeostasis because of chemotherapy, hematopoietic stem cell transplantation, or infection. Previously considered rare, M‐HLH may occur in up to 1% of patients with hematologic malignancies. M‐HLH is often missed or diagnosed late in most published studies, and it has been associated with a poor median survival of less than 2 months. Identification of the clinical and laboratory features specific to M‐HLH in adults may allow early detection, consultation with HLH experts, and intervention. Improved management of adult M‐HLH with optimal combinations of T‐lympholytic and immunosuppressive agents and the incorporation of novel agents based on the pediatric experience hopefully will improve outcomes in adults with M‐HLH. Cancer 2017;123:3229‐40. © 2017 American Cancer Society.