Citations

Abstract Purpose: Treatment options are limited beyond JAK inhibitors for patients with primary myelofibrosis (MF) or secondary MF. Preclinical studies have revealed that PI3Kδ inhibition cooperates with ruxolitinib, a JAK1/2 inhibitor, to reduce proliferation and induce apoptosis of JAK2V617F-mutant cell lines. Patients and Methods: In a phase I dose-escalation and -expansion study, we evaluated the safety and efficacy of a selective PI3Kδ inhibitor, umbralisib, in combination with ruxolitinib in patients with MF who had a suboptimal response or lost response to ruxolitinib. Enrolled subjects were required to be on a stable dose of ruxolitinib for ≥8 weeks and continue that MTD at study enrollment. The recommended dose of umbralisib in combination with ruxolitinib was determined using a modified 3+3 dose-escalation design. Safety, pharmacokinetics, and efficacy outcomes were evaluated, and spleen size was measured with a novel automated digital atlas. Results: Thirty-seven patients with MF (median age, 67 years) with prior exposure to ruxolitinib were enrolled. A total of 2 patients treated with 800 mg umbralisib experienced reversible grade 3 asymptomatic pancreatic enzyme elevation, but no dose-limiting toxicities were seen at lower umbralisib doses. Two patients (5%) achieved a durable complete response, and 12 patients (32%) met the International Working Group-Myeloproliferative Neoplasms Research and Treatment response criteria of clinical improvement. With a median follow-up of 50.3 months for censored patients, overall survival was greater than 70% after 3 years of follow-up. Conclusions: Adding umbralisib to ruxolitinib in patients was well tolerated and may resensitize patients with MF to ruxolitinib without unacceptable rates of adverse events seen with earlier generation PI3Kδ inhibitors. Randomized trials testing umbralisib in the treatment of MF should be pursued.

The classic Philadelphia chromosome–negative myeloproliferative neoplasms (MPN) consist of myelofibrosis, polycythemia vera, and essential thrombocythemia and are a heterogeneous group of clonal blood disorders characterized by an overproduction of blood cells. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for MPN were developed as a result of meetings convened by a multidisciplinary panel with expertise in MPN, with the goal of providing recommendations for the management of MPN in adults. The Guidelines include recommendations for the diagnostic workup, risk stratification, treatment, and supportive care strategies for the management of myelofibrosis, polycythemia vera, and essential thrombocythemia. Assessment of symptoms at baseline and monitoring of symptom status during the course of treatment is recommended for all patients. This article focuses on the recommendations as outlined in the NCCN Guidelines for the diagnosis of MPN and the risk stratification, management, and supportive care relevant to MF.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph) which results from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase CML.

Eosinophilic disorders and related syndromes represent a heterogeneous group of neoplastic and nonneoplastic conditions, characterized by more eosinophils in the peripheral blood, and may involve eosinophil-induced organ damage. In the WHO classification of myeloid and lymphoid neoplasms, eosinophilic disorders characterized by dysregulated tyrosine kinase (TK) fusion genes are recognized as a new category termed, myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA , PDGFRB or FGFR1 or with PCM1-JAK2 . In addition to these aforementioned TK fusion genes, rearrangements involving FLT3 and ABL1 genes have also been described. These new NCCN Guidelines include recommendations for the diagnosis, staging, and treatment of any one of the myeloid/lymphoid neoplasms with eosinophilia (MLN-Eo) and a TK fusion gene included in the 2017 WHO Classification, as well as MLN-Eo and a FLT3 or ABL1 rearrangement.

PURPOSE: Patients with acute myeloid leukemia with high-risk cytogenetics in first complete remission (CR1) achieve better outcomes if they undergo allogeneic hematopoietic cell transplantation (HCT) compared with consolidation chemotherapy alone. However, only approximately 40% of such patients typically proceed to HCT. METHODS: We used a prospective organized approach to rapidly identify donors to improve the allogeneic HCT rate in adults with high-risk acute myeloid leukemia in CR1. Newly diagnosed patients had cytogenetics obtained at enrollment, and those with high-risk cytogenetics underwent expedited HLA typing and were encouraged to be referred for consultation with a transplantation team with the goal of conducting an allogeneic HCT in CR1. RESULTS: Of 738 eligible patients (median age, 49 years; range, 18-60 years of age), 159 (22%) had high-risk cytogenetics and 107 of these patients (67%) achieved CR1. Seventy (65%) of the high-risk patients underwent transplantation in CR1 ( P < .001 compared with the historical rate of 40%). Median time to HCT from CR1 was 77 days (range, 20-356 days). In landmark analysis, overall survival (OS) among patients who underwent transplantation was significantly better compared with that of patients who did not undergo transplantation (2-year OS, 48% v 35%, respectively [ P = .031]). Median relapse-free survival after transplantation in the high-risk cohort who underwent transplantation in CR1 (n = 70) was 11.5 months (range, 4-47 months), and median OS after transplantation was 14 months (range, 4-44 months). CONCLUSION: Early cytogenetic testing with an organized effort to identify a suitable allogeneic HCT donor led to a CR1 transplantation rate of 65% in the high-risk group, which, in turn, led to an improvement in OS when compared with the OS of patients who did not undergo transplantation.

Abstract Background: Therapies for myelofibrosis (MF) are limited and most are palliative. The JAK1/2 inhibitor ruxolitinib reduces spleen size and MF-related symptoms and improves survival, but can be limited by dose-dependent anemia and thrombocytopenia. Moreover, nearly half of ruxolitinib responders relapse within 5 years. PI3Kd is highly expressed in MF patient samples, independent of ruxolitinib pre-exposure. In JAK2-mutated cell lines, inhibition of PI3K/AKT signaling reduced proliferation and clonogenic potential. The once daily, next generation PI3Kd inhibitor TGR-1202 inhibited PI3K/AKT signaling and led to apoptosis in leukemia and lymphoma cell lines and was well-tolerated in clinical studies, with a toxicity profile distinct from that of ruxolitinib and other PI3Kd inhibitors. We hypothesized that adding TGR-1202 to ruxolitinib could resensitize or augment the response of MF patients with lost or suboptimal response to single-agent ruxolitinib. Objective: To assess safety of TGR-1202 in combination with ruxolitinib in MF patients Secondary Objectives: Hematologic response, symptom assessment Methods: MF patients who had sub-optimal responses to ruxolitinib continued their highest tolerated dose of ruxolitinib without change for ≥ 8 weeks, and were assigned to escalating doses of TGR-1202 in a standard 3+3 algorithm. Adverse events (AEs) were graded by NCI-CTCAE v4.03. Efficacy was assessed according to IWG-MRT consensus response criteria. Symptoms were assessed by the MPN symptom assessment form total symptom score (TSS). All patients received Pneumocystis pneumonia prophylaxis after cycle 1. Results: Eleven MF patients were enrolled and received 400 mg (n=3), 800 mg (n=6), or 600 mg TGR-1202 (n=2) daily. Nine were evaluable for response. Median age was 66y, 73% were male. All had ECOG PS 0-1. Five patients had mutations in JAK2, 4 in CALR, and 3 in MPL; these were mutually exclusive with exception of 1 patient with CALR and MPL mutations (Table 1). Median number of cycles of TGR-1202 + ruxolitinib treatment was 5 (1-13). Grade 2 anemia was the most common AE (Table 2). Two patients had asymptomatic Grade 3 elevations in amylase and lipase that persisted after drug was held, meeting criteria for dose limiting toxicities (DLTs) in 2 separate cohorts (TGR-1202 800mg+ruxolitinib 15mg BID and TGR-1202 800mg+ruxolitinib 10mg BID). Both patients had peak plasma TGR-1202 concentrations 1.5-2x higher than the other patients receiving 800mg TGR-1202, although steady-state levels were equivalent. The maximum tolerated dose (MTD) of TGR-1202 in combination with ruxolitinib was not established. Two patients went off-study due to AEs, and 3 due to progressive disease. One of 9 evaluable patients achieved complete remission and 7 had stable disease. Seven of the 9 evaluable patients had improvement in hematologic parameters and 8 had reduced MF symptoms with a median 33% decrease in TSS (Fig. 1). Conclusions: TGR-1202 + ruxolitinib was well-tolerated. Pharmacokinetic data were consistent with single-agent TGR-1202 (unpublished data), indicating that ruxolitinib does not alter absorption or metabolism of TGR-1202. Grade 3 elevations in amylase and lipase were considered DLTs, per protocol. Although the clinical significance of these asymptomatic laboratory findings is not clear, the protocol was amended to further assay these labs and to exclude concomitant medications with the potential to increase amylase/lipase. Importantly, no grade ≥3 hepatotoxicity, colitis, or thrombocytopenia was seen and no MTD was found. Although only one patient achieved CR, 89% demonstrated clinical benefit with the addition of TGR-1202 to ruxolitinib, supporting further exploration of this combination. Disclosures Strickland: Alexion Pharmaceuticals: Consultancy; Ambit: Consultancy; Baxalta: Consultancy; Boehringer Ingelheim: Consultancy, Research Funding; CTI Biopharma: Consultancy; Daiichi Sankyo: Consultancy; Sunesis Pharmaceuticals: Consultancy, Research Funding; Abbvie: Research Funding; Astellas Pharma: Research Funding; Celator: Research Funding; Cyclacel: Research Funding; GlaxoSmithKline: Research Funding; Karyopharm Therapeutica: Research Funding; Sanofi: Research Funding. Miskin:TG Therapeutics, Inc: Employment, Equity Ownership. Cavers:TG Therapeutics: Employment, Equity Ownership. Sportelli:TG Therapeutics, Inc.: Employment, Equity Ownership. Michaelis:Pfizer: Equity Ownership; Cellgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte Corporation: Consultancy, Honoraria. Mesa:CTI: Research Funding; Promedior: Research Funding; Celgene: Research Funding; Gilead: Research Funding; Incyte: Research Funding; Galena: Consultancy; Ariad: Consultancy; Novartis: Consultancy. Savona:Amgen Inc.: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Research Funding; Ariad: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Sunesis: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees.

Abstract Background: Adult acute myeloid leukemia (AML) patients with high-risk cytogenetics have a significantly worse survival compared to similarly treated intermediate- or favorable-risk patients. Although prior studies suggest better outcome in high-risk AML patients in first complete remission (CR1) who undergo allogeneic hematopoietic cell transplantation (HCT) compared with consolidation chemotherapy, only 40% of patients proceed to HCT. The lack of a matched sibling donor (available in about 33%) should not be a barrier to HCT since alternative donors are available for the large majority of high-risk AMLpatients and recent data suggest outcomes after allogeneic HCT from fully matched unrelated donors are similar to those following matched related donor transplantation. We sought to determine if a prospective organized effort could rapidly identify alternative donors to improve the historical 40% allogeneic HCT rate in high-risk CR1 AML patients ≤ age 61. Secondly, we hypothesized that transplanting significantly more adults with high-risk AML in CR1 would lead to an improved outcome compared with the historical relapse-free survival (RFS) of 22%. Patients and Methods: Adult patients between ages 18 and 60 years with untreated AML were randomized to receive induction therapy with standard cytarabine plus daunorubicin (7+3; n=261), idarubicin with high-dose cytarabine (IA; n=261), or IA with vorinostat (IA+V; n=216). Conventional cytogenetics were obtained at time of enrollment and used to determine risk classification by standard criteria. All patients with high-risk cytogenetics underwent expedited HLA-typing. High-risk patientswere encouraged tobe referred for consultation with a transplant team with the goal of conducting an allogeneic HCT in CR1. Results: Of 738 eligible patients (median age, 49 years; range, 18-60), 159 (22%) had high-risk cytogenetics, of whom 60 (38%), 61 (38%), and 38 (24%) received induction with 7+3, IA, or IA+V, respectively. A total of 107 of the 159 high-risk patients achieved CR/CRi (67%). HCT was performed in 317 of all 738 patients (43%) and 68 (64%) of the high-risk patients received a transplant in CR1 (p<0.001 compared to historical rate of 40%). Twenty-five (37%) had a matched related donor, 31 (45%) had a matched unrelated donor, 3 (4%) had a mismatched related donor, 8 (12%) had a mismatched unrelated donor, and 1 (1%) received an umbilical cord blood transplant. Sixty-six high-risk patients transplanted in CR/CRi have detailed data. Median time to HCT from CR1 was 76 days (range, 20-365). Fifty-seven patients (86%) received a myeloablative regimen and 9 (14%) reduced-intensity conditioning. Reasons for 39 high-risk CR1 patients not receiving a transplant in CR1 were: co-morbidities (n=1), death (n=6), no insurance (n=1), no donor (n=1), physician decision (n=3), patient decision (n=3), relapse (n=6), other (n=10), or unknown (n=8). The 2-year RFS estimate in the entire high-risk cohort is 32%, significantly higher than the 22% historical rate (p=0.05). Median RFS in the high-risk CR1 cohort (n=107) was 10 months [range, 1-32* (censored) months]. RFS and OS were similar among HCT patients using matched related [1 year estimates: 40% (95% CI 27%, 74%) and 56% (37%, 74%), respectively] and matched unrelated [1 year estimates: 52% (37%, 75%) and 56% (37%, 74%), respectively] donors in CR1. The HR (reference = unrelated) for RFS was 0.67 (0.32, 1.37) and for OS was 0.88 (0.41, 1.90). Median overall survival (OS) among all patients in the high-risk cohort (n=159) was 12 months [range, 1-33* (censored) months] and was 18 months [range 3-33* (censored) months] for those transplanted in CR1 (Fig. 1). Conclusions: In newly diagnosed adults with AML age 18-60, early cytogenetic testing with an organized effort to identify a suitable allogeneic HCT donorled to a CR1 transplant rate of 64% in the high-risk group, which in turn led to a significant improvement in RFS over historical controls. Better outcomes in poor prognosis AML patients may be achieved simply by rapidly finding unrelated donors and performing allogeneic HCT in CR1 as soon as possible. Clinical Trials Registry: NCT #0180233; Support: NIH/NCI grants: CA180888, CA180819, CA18020, CA180821, CA180863, CA077202; CCSRI #021039 Figure 1 Overall Survival (OS) among all patients in the high-risk cohort, all high-risk patients achieving CR1, and in those high-risk patients transplanted in CR1. Figure 1. Overall Survival (OS) among all patients in the high-risk cohort, all high-risk patients achieving CR1, and in those high-risk patients transplanted in CR1. Disclosures Othus: Glycomimetics: Consultancy; Celgene: Consultancy. Radich:Novartis: Consultancy, Other: laboratory contract; ARIAD: Consultancy; Pfizer: Consultancy; TwinStrand: Consultancy; Bristol-MyersSquibb: Consultancy. Strickland:Alexion Pharmaceuticals: Consultancy; Ambit: Consultancy; Baxalta: Consultancy; Boehringer Ingelheim: Consultancy, Research Funding; CTI Biopharma: Consultancy; Daiichi Sankyo: Consultancy; Sunesis Pharmaceuticals: Consultancy, Research Funding; Abbvie: Research Funding; Astellas Pharma: Research Funding; Celator: Research Funding; Cyclacel: Research Funding; GlaxoSmithKline: Research Funding; Karyopharm Therapeutica: Research Funding; Sanofi: Research Funding. Savoie:AbbVie: Consultancy; Lundbeck: Consultancy; BMS: Consultancy, Honoraria; Velgene: Consultancy; Pfizer: Consultancy; Amgen: Consultancy; Novartis: Consultancy, Honoraria; Jazz: Consultancy. Sekeres:Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Stone:Amgen: Consultancy; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Xenetic Biosciences: Consultancy; Jansen: Consultancy; Pfizer: Consultancy; ONO: Consultancy; Juno Therapeutics: Consultancy; Merck: Consultancy; Roche: Consultancy; Seattle Genetics: Consultancy; Sunesis Pharmaceuticals: Consultancy; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy; Novartis: Consultancy; Celator: Consultancy; Karyopharm: Consultancy. Erba:Seattle Genetics: Consultancy, Research Funding; Pfizer: Consultancy; Jannsen: Consultancy, Research Funding; Juno: Research Funding; Celator: Research Funding; Ariad: Consultancy; Agios: Research Funding; Amgen: Consultancy, Research Funding; Novartis: Consultancy, Speakers Bureau; Millennium Pharmaceuticals, Inc.: Research Funding; Incyte: Consultancy, DSMB, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Gylcomimetics: Other: DSMB; Sunesis: Consultancy; Daiichi Sankyo: Consultancy; Astellas: Research Funding.

Abstract Introduction: Midostaurin, a multitargeted tyrosine kinase inhibitor (TKI), plus induction and consolidation chemotherapy followed by single-agent midostaurin maintenance therapy resulted in significant benefits in event-free and overall survival (OS) in adults with newly diagnosed FLT3-mutated acute myeloid leukemia (AML) compared with placebo (RATIFY study; Stone et al, N Engl J Med, 2017). In RATIFY, patients who received allogeneic hematopoietic stem cell transplant (alloSCT) did not receive midostaurin maintenance. Despite alloSCT providing the highest likelihood of sustained remission, relapse rates remain high (30%-59%; Schiller et al, Biol Blood Marrow Transplant, 2016), especially in patients with FLT3-internal tandem duplication-positive (ITD+) AML. Posttransplant maintenance therapy may improve this outcome. Here, we report the primary results from RADIUS, a randomized, open-label, phase 2 exploratory trial (NCT01883362) that investigated whether the addition of midostaurin to standard of care (SOC) after alloSCT could reduce the risk of relapse in patients with FLT3-ITD+ AML. Methods: Adults (aged 18-70 y) who had undergone myeloablative alloSCT in first complete remission (CR1), had achieved hematologic recovery, and were transfusion independent were eligible. Patients enrolled postengraftment and were randomized to receive SOC with or without midostaurin 50 mg twice daily continuously (4-week cycles) for up to 12 cycles. Study treatment started 28 to 60 days post-alloSCT and patients were followed for ≥24 months post-alloSCT. The primary endpoint was relapse-free survival (RFS) at 18 months post-alloSCT. Secondary endpoints included safety and disease-free survival (DFS), OS, and RFS at 24 months post-alloSCT. The study was not adequately powered to detect a statistical difference between the 2 arms; a sample size of 60 was calculated to detect a 50% reduction in the risk of relapse. Results: 60 patients were randomized (30 per arm). Baseline characteristics were generally balanced between the 2 arms. Overall, 30 patients completed 12 cycles of study treatment (14 with SOC; 16 with midostaurin). The median exposure to midostaurin was 10.5 months (range, 0.2 to 12.0 months) and the median dose intensity was 93 mg/day (range, 15-100 mg/day). Early treatment discontinuations were similar between arms (15 in the SOC arm; 13 in the midostaurin arm), frequently due to adverse events (AEs; 3% vs 23%) and consent withdrawal (20% vs 7%). Among 6 patients who withdrew consent in the SOC arm, 2 did so to pursue other TKI therapies. Midostaurin dose modifications occurred in 19 patients (63%), mostly due to AEs (84%); 1 instance was due to receiving a concomitant CYP3A4 inhibitor. With an estimated 18-month RFS (95% CI) of 76% (54%-88%) in the SOC arm and 89% (69%-96%) in the midostaurin arm, estimated relapse rates were 24% and 11%, respectively, which is a 46% relative reduction in the risk of relapse with the addition of midostaurin (Figure 1). At 18 months, the median RFS was not reached in either arm. Longer follow-up at 24 months (data not yet matured) will be presented, including RFS, OS, and DFS. In the SOC and midostaurin arms, AEs were reported in 87% and 100% of patients, respectively (the most common any-grade AE was vomiting: 23% vs 73%; Figure 2); serious AEs were reported in 57% and 30% of patients, respectively, with diarrhea (7% vs 13%), nausea (10% vs 3%), vomiting (10% vs 3%), and pyrexia (7% vs 7%) being the most common. Overall, 8 patients discontinued midostaurin therapy due to AEs (mostly gastrointestinal related) and 12 died on study (all during the follow-up phase; 8 in the SOC arm and 4 in the midostaurin arm [n=4 vs n=2 due to AML disease progression]). Rates of graft-vs-host disease (GVHD) were generally similar between the SOC and midostaurin arms (overall, 70% vs 73%; acute GVHD, 53% vs 57% [grade 2/3 events: 37% vs 30%; no grade 4 events]; chronic GVHD, 47% vs 37% [most events were mild or moderate; severe events: 1 with SOC and 2 with midostaurin]). Conclusions: Adding midostaurin to SOC reduced the risk of relapse at 18 months post-alloSCT by 46% (vs SOC). The safety profile of single-agent midostaurin was consistent with previous reports; no major safety concerns were identified when adding midostaurin to SOC following alloSCT. These data suggest that midostaurin monotherapy can be safely administered for ≤1 year and may improve outcomes in patients who undergo alloSCT in CR1. Disclosures Maziarz: Novartis Pharmaceuticals Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Consultancy, Honoraria; Juno Therapeutics: Consultancy, Honoraria; Kite Therapeutics: Honoraria; Athersys, Inc.: Patents & Royalties. Scott:Agios: Consultancy; Novartis: Research Funding; Celgene: Consultancy, Research Funding; Alexion: Consultancy. Deol:Kite Pharmaceuticals: Consultancy; Novartis: Consultancy. Kim:Novartis: Consultancy, Honoraria, Research Funding; Briston-Meyers Squibb: Consultancy, Honoraria, Research Funding; Paladin: Consultancy; Pfizer: Consultancy. Haines:Novartis: Employment. Bonifacio:Novartis: Employment. Rine:Novartis: Employment. Purkayastha:Novartis Pharmaceuticals Corporation: Employment.

Abstract Background: A majority of younger pts with AML receive initial therapy with a 7+3 scheme. Escalated doses of daunorubicin (dauno) in combination with standard doses of ara-C may lead to improved outcomes (Fernandez; NEJM 2009). A phase II trial of idarubicin and high-dose ara-C (IA) in combination with the histone deacetylase inhibitor vorinostat (IA+V) resulted in historically high response rates compared to IA or 7+3 (Garcia-Manero; JCO 2011). SWOG 1203 tested whether a high-dose ara-C induction with or without vorinostat could result in improved outcomes for younger AML pts compared to 7+3. Methods: The primary endpoints were comparison of event-free survival (EFS) of 7+3 vs IA vs IA+V and evaluating the frequency of allogeneic hematopoietic cell transplantation. Secondary endpoints included toxicity, remission rate, relapse-free survival (RFS), and overall survival (OS) according to treatment arm, and by cytogenetic and molecular subgroups. Because of the historical trend of cured pts in S0106, EFS was modeled with an exponential cure model, and it was assumed IA or IA+vorinostat increased the proportion of pts cured from 35% to 45% and increased median EFS among those not cured from 4.7 months to 7.1 months. Main inclusion criteria included a diagnosis of previously untreated non-APL AML by WHO criteria, age 15 to 60 years, and preserved cardiac function but no severe comorbidities. Pts with known CBF rearranged or FLT3 mutant leukemias were eligible if no other alternative clinical trials existed. Treatment was as follows: Induction: 7+3 arm: dauno 90 mg/m2 IV QD x 3 on days 1-3 with ara-C CI 100 mg/m2 QD x 7 days on days 1 to 7. IA arm: ida 12 mg/m2 QD x 3 on days 1 to 3 with 24 hours CI ara-C 1.5 gm/m2 QD for 4 days on days 1 to 4. IA+vorinostat was as IA but with vorinostat 500 mg orally TID for 3 days on days 1 to 3. Consolidation: 7+3 arm: standard high-dose ara-c at 3 gm/m2 over 3 hrs q12 hours x 6 doses for 1 to 4 cycles depending on transplant availability. IA arm: idarubicin 8 mg/m2 IV QD x 2 days on days 1 to 2 with ara-C 0.75 gm/m2 CI for 3 days on days 1 to 3 for 4 cycles. The number of consolidation cycles depended on transplant indication; a secondary aim of the study was to transplant all cytogenetically-determined high risk pts (presented in a different abstract). Results: Of 754 pts randomized, 738 were eligible (261 to 7+3, 261 to IA, and 216 to IA+V). Baseline characteristics were well balanced among all three groups. Most (75%) pts were between 40 and 60 years, 51% were male, median (range) WBC and platelets were 10.8 (0.3-800) and 49 (3-3900), respectively; marrow blast percentage was 60% (0%-100%); cytogenetics were favorable in 13% of pts, intermediate in 63%, and high-risk in 22%; FLT-3 was mutated in 21% and unknown in 31%; NPM1 was mutated in 20% and was unknown in 37%. Complete remission (CR) rates were 75% for 7+3, 79% for IA, and 77% for IA+V (p=0.58). Significantly more pts received reinduction with 7+3 (24%) versus 11% with IA and 9% with IA+V (p=0.001). 48% of intermediate and unfavorable risk pts received transplant in CR1, with no significant differences among arms (p=0.44). There were no significant differences in EFS, RFS or OS among all three arms (Figure 1, all p>0.5). By cytogenetic or molecular group, there were no differences in outcome for any standard risk subset (FLT-3, NPM1, or CEBPα or cytogenetic subset), although pts with favorable cytogenetics had significantly better EFS, RFS and OS with 7+3 therapy compared to IA or IA+V (Figure 2, all p≤0.015). 30% of pts received 1 consolidation cycle, 18% 2, 16% 3, and 37% 4 cycles. Grade 5 induction toxicity rates were 4% (7+3), 8% (IA), and 9% (IA+V) by arm (p=0.07), and for toxicities related to therapy, 2%, 7%, 8%, respectively (p=0.01). Grade 4 induction toxicity rates were similar across arms (p=0.38). Conclusion: Treatment with IA is not more effective than 7+3 in younger pts with AML. Outcomes with IA or IA plus vorinostat are similar. In pts with favorable cytogenetics, outcomes were inferior with IA or IA+V when compared to 7+3, perhaps related to use of lower doses of ara-C during consolidation. Clinical Trials Registry: NCT #0180233 Support: NIH/NCI grants CA180888, CA180819, CA18020, CA180821, CA180863, CA077202; CCSRI grant #021039 Disclosures Othus: Glycomimetics: Consultancy; Celgene: Consultancy. Radich:Novartis: Consultancy, Research Funding; Ariad: Consultancy; BMS: Consultancy. Strickland:Alexion Pharmaceuticals: Consultancy; Astellas Pharma: Research Funding; Baxalta: Consultancy; Cyclacel: Research Funding; Celator: Research Funding; Abbvie: Research Funding; Ambit: Consultancy; Boehringer Ingelheim: Consultancy, Research Funding; CTI Biopharma: Consultancy; Daiichi Sankyo: Consultancy; Sunesis Pharmaceuticals: Consultancy, Research Funding; GlaxoSmithKline: Research Funding; Karyopharm Therapeutica: Research Funding; Sanofi: Research Funding. Savoie:Novartis: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria; Pfizer: Consultancy; Celgene: Consultancy; Amgen: Consultancy; Jazz: Consultancy; Lundbeck: Consultancy. Sekeres:Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Stone:Amgen: Consultancy; Karyopharm: Consultancy; Juno Therapeutics: Consultancy; Roche: Consultancy; Pfizer: Consultancy; Agios: Consultancy; Jansen: Consultancy; Xenetic Biosciences: Consultancy; Celator: Consultancy; Merck: Consultancy; Abbvie: 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; Novartis: Consultancy; ONO: Consultancy; Seattle Genetics: Consultancy; Sunesis Pharmaceuticals: Consultancy. Erba:Sunesis: Consultancy; Seattle Genetics: Consultancy, Research Funding; Celgene: Consultancy, Speakers Bureau; Gylcomimetics: Other: DSMB; Ariad: Consultancy; Astellas: Research Funding; Gylcomimetics: Other: DSMB; Amgen: Consultancy, Research Funding; Pfizer: Consultancy; Gylcomimetics: Other: DSMB; Astellas: Research Funding; Astellas: Research Funding; Amgen: Consultancy, Research Funding; Daiichi Sankyo: Consultancy; Celgene: Consultancy, Speakers Bureau; Juno: Research Funding; Seattle Genetics: Consultancy, Research Funding; Jannsen: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Celgene: Consultancy, Speakers Bureau; Daiichi Sankyo: Consultancy; Sunesis: Consultancy; Millennium Pharmaceuticals, Inc.: Research Funding; Incyte: Consultancy, DSMB, Speakers Bureau; Agios: Research Funding; Celator: Research Funding; Ariad: Consultancy; Agios: Research Funding; Incyte: Consultancy, DSMB, Speakers Bureau; Jannsen: Consultancy, Research Funding; Juno: Research Funding; Agios: Research Funding; Jannsen: Consultancy, Research Funding; Novartis: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Incyte: Consultancy, DSMB, Speakers Bureau; Juno: Research Funding; Pfizer: Consultancy; Millennium Pharmaceuticals, Inc.: Research Funding; Celator: Research Funding; Daiichi Sankyo: Consultancy; Agios: Research Funding; Celator: Research Funding; Daiichi Sankyo: Consultancy; Millennium Pharmaceuticals, Inc.: Research Funding; Pfizer: Consultancy; Celator: Research Funding; Jannsen: Consultancy, Research Funding; Sunesis: Consultancy; Seattle Genetics: Consultancy, Research Funding; Astellas: Research Funding; Ariad: Consultancy; Ariad: Consultancy; Millennium Pharmaceuticals, Inc.: Research Funding; Seattle Genetics: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Sunesis: Consultancy; Pfizer: Consultancy; Juno: Research Funding; Celgene: Consultancy, Speakers Bureau; Gylcomimetics: Other: DSMB.