Large granular lymphocytic leukemia (LGLL) represents a clonal/oligoclonal lymphoproliferation of cytotoxic T and natural killer cells often associated with STAT3 mutations. When symptomatic, due to mostly anemia and neutropenia, therapy choices are often empirically-based, because only few clinical trials and systematic studies have been performed. Incorporating new molecular and flow cytometry parameters, we identified 204 patients fulfilling uniform criteria for LGLL diagnoses and analyzed clinical course with median follow-up of 36 months, including responses to treatments. While selection of initial treatment was dictated by clinical features, the initial responses, as well as overall responses to methotrexate (MTX), cyclosporine (CsA), and cyclophosphamide (CTX), were similar at 40-50% across drugs. Sequential use of these drugs resulted in responses in most cases: only 10-20% required salvage therapies such as ATG, Campath, tofacitinib, splenectomy or abatacept. MTX yielded the most durable responses. STAT3-mutated patients required therapy more frequently and had better overall survival.

Molecular mutations are routinely incorporated into the risk stratification of newly diagnosed acute myeloid leukemia (AML) patients (pts). However, their prognostic impact in relapsed AML has not been well characterized. To better understand the landscape and prognostic impact of molecular mutations in relapsed AML, we retrospectively examined pts with AML in first relapse. Methods: We performed multi-amplicon targeted deep sequencing on samples from bone marrow and peripheral blood of pts diagnosed with AML in first relapse at our institution between the years 2002-2013. A multiple gene sequencing panel of 64 genes that have been described as recurrently mutated in myeloid malignancies was applied. Genes were analyzed individually and grouped based on their functional pathways: RNA splicing, RNA-helicase family, DNA methylation/epigenetic, transcription factors, signal transduction/ receptors, histone/ chromatin modification, cohesion complex. Cytogenetic (CG) risk was ascribed by CALGB/Alliance 8461 criteria. The primary endpoints were response to salvage therapy and overall survival from relapse (OS-R). Binary logistic and proportional hazards models were used for univariable and multivariable analyses. Multivariable analyses of individual genes and functional groups used a stepwise variable selection algorithm and were based on the genes and gene groups found to be significant in univariable analysis at p < 0.20. Results: Data from 74 pts were analyzed. The median age at diagnosis was 61 years (range 27-77). CG risk at diagnosis: good (17%), intermediate (42%), miscellaneous (15%), poor (26%). At the time of relapse, 68% of pts received intensive salvage chemotherapy [i.e. MEC (mitoxantrone, etoposide, cytarabine), high dose cytarabine], 14% supportive care, and 19% low dose therapy. Sixteen percent of pts received an allogeneic hematopoietic stem cell transplant. The most common mutations were found in NPM1 (16%), DNTM3A (15%), IDH2 (14%), and PHF6 (10%). Overall, 19 pts (26%) had no mutations, 25 (34%) had 1, 12 (16%) had 2, 11 (15%) had 3, and 7 (9%) had > 3 mutations. Fifty-two percent of pts achieved a complete remission (CR) or CR with incomplete count recovery (CRi) with salvage therapy (95% CI: 39-64%) and median OS-R was 5.2 months. In multivariable analyses, the number of mutations (0, 1, >1) in DNMT3A, TP53, NRAS, and ASXL1 (panel 1) was the only factor found to be independently associated with worse OS-R and response to salvage therapy (p< 0.0001 and 0.03, respectively). Adjusting for age, CG risk, and treatment, the number of mutations in panel 1 remained a significant predictor of OS-R (p=0.003) but not of response to salvage therapy (p=0.23). Multivariable analyses of panel 1 and conventional CG risk suggested that both factors contained prognostic information (p < 0.0001 and 0.07, respectively); and that a modified CG risk classification system could be defined using a simple scoring algorithm that assigns points to each conventional CG risk group and the number of panel 1 mutations that are proportional to the corresponding regression coefficients from the model and then summing the number of points present (Table 1). Based on the scoring system, 3 prognostic groups can be defined (Figure 1). Table 1. Scoring Algorithm Factor Points CG Risk  Good 0  Intermediate 2  Miscellaneous 2  Poor 3 Number of mutations in panel 1  0 0  1 3  >1 6 Conclusions: Molecular mutations are prognostic for OS-R and may help identify patients who would benefit from novel therapies at the time of relapse. Specific predictive mutations included genes related to DNA methylation and histone modification suggesting that targeting these specific factors may improve outcome. Figure 1. Prognostic Groups Figure 1. Prognostic Groups Disclosures Carew: Boehringer Ingelheim: Research Funding. Sekeres:Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; TetraLogic: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees.

Background: For patients (pts) with AML undergoing induction chemotherapy (IC), incomplete platelet (plt) recovery can lead to an increased risk of bleeding, prolonged dependence on plt transfusions, plt alloimmunization, as well as delay in post-remission therapy. Eltrombopag is a thrombopoietin receptor agonist that stimulates megakaryopoiesis and has anti-leukemic effects. Herein, we present the final results of a phase 2 trial evaluating the efficacy of eltrombopag in accelerating plt count recovery in older AML pts receiving IC (NCT02071901). Methods: All newly diagnosed FLT3-negative AML pts > 60 years (yrs) with ECOG scores of 0-2, no active second malignancy, and no evidence of marrow fibrosis at the time of AML diagnosis were included. Acute promyelocytic (AML-M3), megakaryocytic (AML-M7), and AML arising from myeloproliferative neoplasms were excluded. Pts with any arterial or venous thrombotic event (excluding line thrombosis) within the past 12 months were excluded. IC consisted of an anthracycline (daunorubicin at 45 mg/m2 x 3 days) and infusional cytarabine (100 mg/m2 x 7 days). Eltrombopag was administered starting day 15 (range, day 15-18) of IC in pts who had marrow blasts <5% on day 14 (range, day 14-17). The primary endpoint was the proportion of pts achieving plt count > 50000/µL by day 24 of IC. In a historical cohort of 220 older AML pts (excluding APL and AML-M7) treated with IC between 2004 and 2011 at Cleveland Clinic, 60% achieved a plt count > 50,000/µL by day 24. Eltrombopag was administered at a dose of 200 mg with a one-time maximal dose escalation to 300 mg daily if plts remained < 50,000/µL after 2 weeks on treatment. Eltrombopag was discontinued once plts exceeded 100,000/µL. Informed consent was obtained prior to start of IC, and eligibility was determined on day 14. Results: Between 9-2014 and 9-2018, 93 pts were consented, of whom 31 met the eligibility criteria. Sixty seven percent of pts were ineligible as they had >5% blasts on day 14 marrow and the remaining met one or more of the following exclusion criteria: acute clinical worsening; use of supraphysiologic dose of steroids (n=1); marrow fibrosis (n=1); active second malignancy (n=1); elevated transaminases (n=5), and elevated serum creatinine (n=1). Median age was 67 years (range, 60-78), 38% were female, and 81% had a good ECOG status (ECOG 0 or 1). Most pts (84%) had de novo AML, 16% had secondary AML. By CALGB/Alliance criteria, 82% had intermediate cytogenetics, 9% had adverse karyotype and in 9% cytogenetic analysis was unsuccessful. The median eltrombopag treatment duration was 10 days (range, 8-11 d), and no dose escalations were required. Trends in the levels of plt count over time are shown in Figure 1. Median times from the start date of eltrombopag to plt >50,000/µL, and >100,000/µL were 7 d (range, 6-8) and 10 d (range, 8-11), respectively (Figure 2). By day 24 of IC, 30 of 31pts (97%) had plt >50,000/µL. The median peak plt count reached on eltrombopag was 606,000/µL (range, 280- 1,935,000/µL). The median time to reach peak plt count from start date of eltrombopag was 14 d (range, 13-36). Pts received a median of 4 units of plt transfusions (range, 3-11) in the first 14 days of induction (1 unit every 3.6 days), while during the eltrombopag treatment period, the median requirement decreased to 2 units (range, 0-6) or 1 unit every 4.8 d (P=.04). Ninety percent of pts achieved complete remission at a median time of 30 d [95% confidence interval (CI), 25-34d] from IC. No death occurred during treatment. The most common any grade toxicities (incidence > 15%) were maculopapular rash (28%), nausea (24%), increased alkaline phosphatase (24%), anorexia (20%), headache (20%), increased aspartate aminotransferase (16%), hypocalcemia (16%), and hypokalemia (16%). Grade 3/4 toxicities were reported at 4% (n=1) for febrile neutropenia, fever, pain, decreased white blood cell count, hypocalcemia, hypokalemia, generalized muscle weakness, maculopapular rash, and thromboembolic event. Median overall survival time from IC was 11.2 months (95% CI, 1.9, 14.8 m). Conclusion: In this study, eltrombopag appeared to hasten plt recovery and reduce plt transfusions without increasing rates of refractory disease in older FLT3-negative AML pts undergoing IC, without any limiting toxicities. Additional analyses are currently underway to evaluate durability of platelet responses, responses in other cell lineages and survival. Disclosures Mukherjee: Bristol-Myers Squibb: Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees; McGraw Hill Hematology Oncology Board Review: Other: Editor; Pfizer: Honoraria; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Projects in Knowledge: Honoraria; Celgene Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Partnership for Health Analytic Research, LLC (PHAR, LLC): Consultancy. Hobbs:Amgen: Research Funding; SimulStat Inc.: Consultancy. Gerds:Celgene Corporation: Consultancy, Research Funding; CTI Biopharma: Consultancy, Research Funding; Sierra Oncology: Research Funding; Roche: Research Funding; Imago Biosciences: Research Funding; Pfizer: Consultancy; Incyte: Consultancy, Research Funding. Advani:Abbvie: Research Funding; Glycomimetics: Consultancy, Research Funding; Kite Pharmaceuticals: Consultancy; Amgen: Research Funding; Pfizer: Honoraria, Research Funding; Macrogenics: Research Funding. Nazha:Tolero, Karyopharma: Honoraria; MEI: Other: Data monitoring Committee; Novartis: Speakers Bureau; Jazz Pharmacutical: Research Funding; Incyte: Speakers Bureau; Daiichi Sankyo: Consultancy; Abbvie: Consultancy. Saunthararajah:EpiDestiny: Consultancy, Equity Ownership, Patents & Royalties; Novo Nordisk: Consultancy. Maciejewski:Novartis: Consultancy; Alexion: Consultancy. Sekeres:Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees; Syros: Membership on an entity's Board of Directors or advisory committees.

Ruxolitinib, is a JAK1/2 inhibitor approved for the treatment of intermediate and high risk myelofibrosis (MF). The recommended starting doses for ruxolitinib, are 20 mg PO BID or 15 mg PO BID if platelet (PLT) counts are ≥200 x109/L or 100 to 200 x109/L, respectively. However, drug related side effects which includes grade 3/4 anemia (45.2%), thrombocytopenia (12.9%), fatigue (25.2%) and diarrhea (23.2%) are common using standard dosing. Moreover 70% of patients (pts) started on the standard regimen require dose reduction because of drug related toxicities. Although hematologic side effects are generally expected during early phases of ruxolitinib therapy and reversible in most cases, a therapeutic approach that can avoid myelosuppression while still providing adequate clinical responses is warranted. Therefore, to obviate toxicities and achieve symptom improvement in pts with MF, we employed a dose escalation (DE, starting at 5 mg QOD) approach for ruxolitinib and compared outcomes with another group that previously received standard regimens (SR, 15 or 20 mg BID). In addition to baseline characteristics, clinical data including hematologic parameters, bone marrow (BM) results, Dynamic International Prognostic Scoring System-Plus (DIPSS-plus) risk, and transfusion (TF) requirement were collected. Hematologic and non-hematologic side effects based on CTCAEv.4 and evidence of clinical response (reduction of splenomegaly by palpation) were assessed at 8, 12 and 16 weeks after starting treatment (post-Tx). Descriptive data were summarized as frequency of counts and percentages and continuous data were presented as mean and ranges and the comparison between two groups was performed. Survival outcomes were analyzed using the Kaplan-Meier method. Plasma concentrations for interleukins (IL) including IL1A, IL1B, IL2, IL4, IL6, IL8, IL10, IL12, IL17A, INFg, TNFa and GM-CSF were also measured pre and post- ruxolitinib treatment using a Multi-Analyte ELISArray Kits (SABiosciences) A total of 42 pts seen in our MPN clinic were studied, including 23 females (54%) and 19 males (46%). The median age of the cohort was 69 (43-83 years). Disease subtypes include 23 PMF, 10 post-PV MF, 6 post-ET MF and, 1 CMML-1. Based on the DIPSS-plus risk score, there were 17 high, 16 intermediate-2, and 8 intermediate-1 risk pts. Thirty-two pts (76%) were JAK2V617F mutant and 10 were wild type. The mean duration of treatment was 8 mos (range, 3-17) and follow up was 11 mos (4-36). Twenty-six pts started on DE and 16 received SR. The mean ruxolitinib dose in the whole cohort was 10 mg BID (range; 5mg QOD-25mg BID). The mean maintenance dose in the DE cohort was 5mg BID while in the SR cohort was 15mg BID. In terms of clinical response, the mean pre and post-Tx spleen size was 13.69 cm and 6.8 cm in the DE cohort compared to 17.68 cm and 13.07 cm in SR cohort (p = .03). In terms of hematological side effects, the DE approach resulted in less frequent grade 3-4 or any grade anemia compared to SR (G3-4: 3% vs. 18%, p =.02; overall anemia: 14% vs. 50%, p =.04). In pts treated with DE and SR, 57% and 75% were TF dependent pre-Tx. Post-Tx, 35% of pts treated with DE became transfusion independent vs 0% in the SR group. The DE approach also resulted in less frequent grade 3-4 or any grade thrombocytopenia compared to SR (G3-4: 11% vs. 31%, p= .04; overall thrombocytopenia: 23% vs. 43%, p=.06). There was no difference in the frequency or degree of neutropenia between the DE and SR treated pts. Non-hematologic side effects were also less frequent in the DE group compared to the SR group (bruising: 36 vs 75%, diarrhea: 28 vs 56%, lower extremity edema: 21% vs 50%, and dizziness: 15 vs 31%). In 3 pts treated with DE, the degree of reticulin fibrosis reduced from MF3 to MF2 confirmed with bone marrow biopsy performed 6-12 months post-Tx. We also compared the differences in cytokine profile between the patients treated with DE (n=2) and SR (N=2). No difference in the degree of reduction of MF relevant cytokines including IL-1A, IL-1B, IL-2, IL-4, IL-6, IL-12, TNF-α and GM-CSF were observed between both groups (p=0.2). At the time of analysis, 38 pts are still alive and no difference in survival were observed between DE and SR treated patients (log rank p=0.69). In conclusion, a dose escalation approach for ruxolitinib therapy is better tolerated and with preserved clinical responses compared to the standard dosing regimen in MF patients. Disclosures: No relevant conflicts of interest to declare.

Introduction In AML patients (pts) undergoing 7+3 induction chemotherapy (IC), incomplete platelet (plt) recovery can lead to increased risks of bleeding, prolonged dependence on plt transfusions, plt alloimmunization, and can hinder post-remission therapy. Eltrombopag is a thrombopoietin receptor agonist that stimulates megakaryopoiesis and has anti-leukemic effects (Erickson-Miller 2008; Will 2009; Roth 2012). We present results of an interim, prespecified analysis of an ongoing trial [ClinicalTrials.gov Identifier: NCT02071901] evaluating the efficacy of eltrombopag in accelerating plt count recovery in older AML pts (>60 years) receiving IC. Methods All newly diagnosed AML pts >60 years (yrs) with ECOG scores of 0-2, no active second malignancy, and no evidence of marrow fibrosis at the time of AML diagnosis were included. Acute promyelocytic leukemia, acute megakaryocytic leukemia, and AML out of myeloproliferative neoplasms were excluded. IC consisted of an anthracycline (daunorubicin at 45_mg/m2 or idarubicin at 12 mg/m2 x 3 days) and infusional cytarabine (100 mg/m2 x 7 days). Eltrombopag was administered starting day 15 (range, day 15-18) of IC in pts who had no morphological evidence of disease (marrow blasts <5%) on day 14 (range, day 14-17). The primary endpoint was the proportion of pts achieving plt>50000/µL by day 24 of IC. Eltrombopag was administered at a dose of 200 mg (100 mg for East Asian [EA] pts) daily with a one-time maximal dose escalation to 300 mg daily (150 mg in EA pts) if plt remained<50,000/µL after 2 weeks on treatment. Eltrombopag was discontinued once plt exceeded 100,000/µL. A two-stage accrual design with a maximum accrual goal of 31 eligible pts was employed with early stopping if>5 of 12 initial eligible pts (42%) failed to achieve plt>50,000/ µL by day 24. Informed consent was obtained prior to start of IC. Results Between 9-2014 and 6-2016, 34 pts were consented of whom 13 met the eligibility criteria. Reasons for failing eligibility (21/34 pts, 62%) included >5% blasts on day 14 marrow (n=15); acute clinical worsening (n=3); marrow fibrosis at AML diagnosis (n=1); active second malignancy (n=1); and elevated transaminases (n=1). Characteristics of the study cohort were: 54% females, 1 pt of EA heritage, median age of 64 yrs (range, 60-71), and 75% with good ECOG status (ECOG 0 or 1). Most pts (62%) had de novo AML, 38% had secondary AML (therapy-related or prior MDS). By CALGB criteria, 82% had intermediate cytogenetics, 9% had adverse karyotype and in 9% cytogenetic analysis was unsuccessful. The median eltrombopag treatment duration was 10 d (range, 8-14 d), and no dose escalations were required. Pts received a median of 4 units of plt (range, 3-11), which equated to 1 unit every 3.6 d, during induction, while during the eltrombopag treatment period, the median requirement decreased to 2 units (range, 0-6) or 1 unit every 4.8 d (p=.04). Pts were transfused with a median of 7 units of red blood cell (RBC) (range, 3-17; 1 unit every 2d) during induction, while on eltrombopag, the median RBC unit transfusion requirement decreased to 4 (range,1-7; 1 unit every 3.6 d) (p=.02). 92% of pts achieved CR at a median time of 32.5 d from IC (range, 29-42). One pt had incomplete CR due to poor ANC recovery. Median times from the start date of IC to plt>20,000/µL,>50,000/µL, and>100,000/µL were 19 d (range, 15-24), 24 d (range, 21-33), and 25 d (range, 23-33), respectively. By day 24 of IC, 8 of 13 pts (62%) had plt>50,000/µL. Trends in the levels of hemoglobin, absolute neutrophil count (ANC), and plt count over time along with median eltrombopag start and stop times are shown in Figure 1. The median peak plt count reached on eltrombopag was 719,000/µL (range, 280-1,935,000/µL). The median time to reach peak plt count from start date of eltrombopag was 19 d (13-28 d). The reported toxicities were all grade 1/2 and included nausea (n=2), decreased vision (n=1), elevated transaminases (n=1 each), and one each with hypokalemia and hypomagnesaemia. Conclusions Our interim analysis suggests that eltrombopag can hasten plt recovery, potentially reduce plt transfusions and increase CR rates in older AML pts undergoing IC without any limiting toxicities.The initial cohort does not show evidence for acceleration of the leukemic process and progression stopping milestones were not reached. The study met its interim objectives and is currently accruing pts. Figure 1 Figure 1. Figure 2 Figure 2. Figure 3 Figure 3. Disclosures Mukherjee: Celgene: Consultancy, Honoraria, Research Funding; Ariad: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding.