ALBERT

Description: Introduction: The role of autologous stem cell transplantation (ASCT) as first line treatment for newly diagnosed patients with myeloma is currently under evaluation given the high response rates to novel induction treatment. The outcomes for patients that do not proceed to ASCT following induction remain unclear and are likely to be determined by genetic risk and response to therapy. In order to evaluate this further, this single arm phase 2 clinical trial conducted at 13 sites in the UK was designed to determine the 2 year progression free survival for patients that achieved ≥ very good partial response (VGPR) following induction therapy without ASCT. Those achieving partial response (PR) were consolidated with ASCT according to routine practice. In this first analysis we report secondary endpoints: disease response and regimen-related toxicity in patients completing induction, including minimal residual disease (MRD) negativity by multiparameter flow cytometry. Methods: Patients with newly diagnosed myeloma eligible for ASCT received PAD (bortezomib 1.3mg/m2 days 1, 4, 8, 11; doxorubicin 9mg/m2 days 1-4 and dexamethasone 40mg days 1-4 (and days 8-11 and 15-18 for the first cycle only)) for up to 6 cycles (minimum of 4). Bortezomib was initially given intravenously (IV), but once approved this was switched to sub-cutaneous (SC). Those failing to achieve PR were offered salvage therapy off protocol. All others had peripheral blood stem cell (PBSC) mobilisation using cyclophosphamide + GCSF, followed by MRD assessment on bone marrow aspirates using multi-parameter flow cytometry. Depending on disease response, patients were then stratified to ASCT (PR) or no further treatment (≥VGPR). Responses were assessed using International uniform response criteria (Durie 2006) by intent-to-treat and toxicity scored according to CTCAE version 4.0. High risk disease was defined by the presence of one or more adverse FISH lesions (t(4;14), t(14;16), t(14;20), del(17p13), +1q21) as described in the MRC Myeloma IX trial. Results: Between March 2011 and January 2014, 153 patients were enrolled (median age of 55, range 28-71 years). 139 (91%) received between 4-6 cycles of PAD. The majority (135, 88%) received SC only bortezomib and 18 (12%) received at least 1 cycle IV. The overall response rate to PAD was 81% with 46% achieving ≥VGPR (sCR: 6 (4%), CR: 13 (8%), VGPR: 51 (33%), PR: 54 (35%)). FISH data was available for 122 patients, 91 (75%) patients were standard risk and 31 (25%) were adverse. Responses were similar irrespective of ISS or genetic risk (standard, ≥VGPR 44%, PR 34%; adverse, ≥VGPR 55%, PR 29%). MRD results are currently available in 70 of the 124 patients achieving PR post PBSC harvest. Of this group 41 achieved ≥VGPR post-harvest (22 MRD+ and 19 MRD-) and hence did not proceed to ASCT, 13 patients achieved CR of which 8 were MRD negative. Toxicity was as expected for PAD and predominantly haematological. Notably the incidence of neuropathy was lower than that previously reported with IV bortezomib. Grade 3-4 events were: neutropenia: 18%; thrombocytopenia 7%. Grade 2-4 peripheral neuropathy was reported in 27% compared to 40% in the HOVON-65/ GMMG-HD4 Trial using IV bortezomib. Grade 1-2 neuropathy was similar for patients who received IV (55.6%) or SC (60%) bortezomib; however only 7% of patients receiving SC bortezomib developed grade 3 neuropathy compared to 28% with the IV route. Conclusions: SC PAD is a highly effective induction regimen for patients with newly diagnosed myeloma achieving a ≥VGPR of 46%. Of the 41 patients achieving ≥VGPR post-harvest with MRD result available, 46% were MRD negative. Response rates were similar across ISS and with adverse FISH. The use of SC bortezomib improved tolerability and substantially reduced neurotoxicity. ISRCTN no: 03381785. Disclosures Popat: Janssen: Honoraria. Cavenagh:Janssen: Honoraria. Schey:Janssen: Consultancy, Honoraria. Cook:Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau. Cook:Janssen: Honoraria, Research Funding. Yong:Janssen: Honoraria.

Description: Key Points No overall clinical benefit was seen after the addition of lestaurtinib to standard chemotherapy for newly diagnosed FLT3-mutated AML. Lower rates of relapse and improved overall survival were seen in patients who achieved sustained levels of FLT3 inhibitory activity.

Description: Background : HSP90 plays an important role in chaperoning key proteins implicated in malignant disease and is a promising therapeutic target. We now report the in vitro and in vivo activity of a novel HSP90 inhibitor of non-ansamycin, non-purine analogue class, KW-2478, (Kyowa Hakko Kirin) in B-cell malignancies including multiple myeloma (MM), B-cell lymphoma (BCL) and mantle cell lymphoma (MCL) cells, and in primary tumour cells from MM and BCL patients. Procedures: The binding affinity of KW-2478 to HSP90 was examined using immobilised human HSP90a and a biotinylated HSP90 binding agent, radicicol (bRD). The effect of KW-2478 on cell viability, cell growth and apoptosis induction were evaluated in cell lines, with KW-2478 induced changes in major HSP90 client proteins studied by Western blotting analysis. The in vivo anti-tumour activity of KW-2478 was evaluated in a human MM xenograft mouse model,. Primary MM cells were studied using a co-culture system with the HS-5 bone marrow stromal cell line (BMSCs), while primary BCL samples were cultured on CHO cells stably transfected to produce CD40L. Results: KW-2478 inhibited the binding of bRD to HSP90α in concentration-dependent manner with an IC50 value of 3.8 nM. KW-2478 clearly inhibited cancer cell growth in all cell lines, with EC50 values from 101–252 nM in BCL, 81.4–91.4 nM in MCL and 120–622 nM in MM. The drug also exhibited potent growth inhibitory activity in primary CLL (n=3) and NHL (n=2) cells with EC50 values of 40–170 nM and 200–400 nM, respectively. In 2 of 4 human primary myeloma cells, KW-2478 at 2 μM inhibited cell growth by at least 50%. The presence of BMSCs did not affect drug activity against primary MM cells and importantly there was little or no effect on cell number or viability of normal BMSCs at up to 20 μM KW-2478. Exposure of MM and BCL cell lines to KW-2478 for 24 hours resulted in the degradation of HSP90 client proteins (IGF-1Rβ and Raf-1) and the induction of HSP70. KW-2478 also induced PARP cleavage and dephosphorylated Erk1/2 in NCI-H929 cells. Further studies in selected cell lines showed that exposure to 1 μM KW-2478 or lower resulted in the depletion of p53 and Akt proteins, a reduction in nuclear NFKB, and the cleavage of caspase-3. In the NCI-H929 xenograft model, KW-2478 (qd×5, i.v.) showed a statistically significant suppression of tumour growth at the doses of 25, 50, 100 and 200 mg/kg. Moreover, tumour regressions were observed at doses of 100 and 200 mg/kg, with a significant decrease in serum M protein concentration at doses of 50, 100 and 200 mg/kg. No severe KW-2478 toxicity was observed as assessed by treatment-related mortality and body weight change. Conclusions: The novel HSP90 inhibitor KW-2478 showed a potent anti-tumour activity both in vitro and in vivo, including activity in primary patient samples. The agent retained its activity in primary myeloma cells in the presence of BMSCs, suggesting that KW-2478 can overcome the protective effect of the bone marrow microenvironment. Additional pharmacokinetic and safety data support the further development of KW-2478 and the drug is currently undergoing clinical evaluation in a phase I trial.

Description: Background: Loss of immune surveillance, mediated through immune checkpoint (ICP) interactions, is thought to be a key step in the development of cancers including AML and HR-MDS. AZA is a standard therapy for pts with AML who are unfit for IC and for pts with HR-MDS. AZA can promote immune recognition of tumor cells and potentially increase expression of ICP molecules, which can mediate resistance to AZA. As myeloid cell lines and samples from pts treated with hypomethylating agents demonstrated up-regulation of PD-L1 expression, blockade of the PD-L1 ICP with durva in combination with AZA may enhance antitumor activity and improve clinical outcomes. Here, we report the final results from a large phase 2 study evaluating the efficacy and safety of AZA+durva vs. AZA alone in pts with HR-MDS or AML (NCT02775903). Methods: This randomized, open-label, international, multicenter study enrolled untreated pts in 2 cohorts: 1) MDS (aged ≥18 years; IPSS-R intermediate, high, and very high) and 2) older AML pts (aged ≥65 years) who were ineligible for IC. All pts had ECOG performance status 0-2 and were separately randomized (1:1) to receive SC AZA 75 mg/m2 Days 1-7 and durva 1500 mg IV on Day 1 Q4W (Arm A) or AZA alone (Arm B) and stratified according to cytogenetic risk (MDS, very good/good/intermediate vs. poor/very poor; AML, intermediate vs. poor). Treatment was planned to continue until progression or unacceptable toxicity. Disease status was evaluated every third treatment cycle. Primary MDS endpoints included overall response rate (ORR, defined as complete remission [CR], marrow [m]CR, partial response [PR], or hematologic improvement [HI]) based on IWG 2006 response criteria, while for AML ORR was defined as CR or CR with incomplete blood recovery (CRi) based on modified IWG 2003 response criteria. Secondary endpoints included PFS, OS, and safety. Peripheral blood samples were collected to assess changes in DNA methylation using the EPIC methylation array (Illumina). Bone marrow (BM) aspirates were obtained for quantitation of PD-L1 surface expression by flow cytometry and values are reported as molecules of equivalent soluble fluorochrome. Results: A total of 213 pts, 84 with MDS (each arm, n=42) and 129 with AML (Arm A, n=64; Arm B, n=65) were randomized. As of October 31, 2018, 32 pts (MDS, n=14; AML, n=18) continued to receive trial treatment while 181 (MDS, n=70; AML, n=111) had discontinued. Baseline demographics and disease characteristics were generally balanced across treatment groups in both cohorts. Median number of treatment cycles for AML Arm A vs. B, 6.5 vs. 6.7; for MDS Arm A vs. B, 7.9 vs. 7.0. No statistically significant differences in ORR between treatment arms were observed in either cohort (Tables 1 and 2). In MDS Arm A vs. B, median OS was 11.6 vs. 16.7 months (mo) and PFS was 8.7 vs. 8.6 mo. In the AML cohort, median OS was 13.0 vs. 14.4 mo and PFS was 8.1 vs. 7.2 mo. Caution should be used when interpreting results because 〉50% of patients were censored. The most frequent TEAEs (≥15%) were hematologic and GI toxicity. In the MDS and AML cohorts, 7 and 17, respectively, immune-mediated AEs were observed; all were treated and resolved. AZA induced similar trends in global hypomethylation, along with focal hypomethylation of PD-L1 and PD-L2 gene loci, at the end of treatment cycle 1 in all treatment groups and cohorts. Mean PD-L1 surface expression in BM immune cells at baseline was highest in monocytes (MDS=1,425; AML=1,536), followed by granulocytes (MDS=550; AML=758) and myeloid blasts (MDS=532; AML=735). Increased surface expression of PD-L1, but not PD-L2, was observed at the end of treatment cycle 3 on BM granulocytes and monocytes from MDS pts and on BM monocytes from AML pts, but no increase was detected on myeloid blasts. Conclusions: To our knowledge, this is the first large randomized trial of AZA with or without ICP blockade in older unfit AML and HR-MDS pts reported to date. No clinically meaningful difference in efficacy was observed between treatments for either cohort. No new safety signals or potential overlapping risks were identified with the combination. While the hypomethylating activity of AZA on PD-L1 gene was confirmed, no treatment-mediated induction of PD-L1 surface expression was observed on myeloid blasts. Disclosures Zeidan: Acceleron Pharma: Consultancy, Honoraria, Research Funding; Celgene Corporation: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Otsuka: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Medimmune/AstraZeneca: Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Research Funding; Trovagene: Consultancy, Honoraria, Research Funding; Incyte: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; ADC Therapeutics: Research Funding; Jazz: Honoraria; Ariad: Honoraria; Agios: Honoraria; Novartis: Honoraria; Astellas: Honoraria; Daiichi Sankyo: Honoraria; Cardinal Health: Honoraria; Seattle Genetics: Honoraria; BeyondSpring: Honoraria. Voso:Novartis: Speakers Bureau; Celgene: Research Funding, Speakers Bureau. Taussig:Celgene: Research Funding. Boss:Celgene Corporation: Employment, Equity Ownership. Copeland:Celgene Corporation: Employment, Equity Ownership. Gray:Celgene Corporation: Employment, Equity Ownership. Previtali:Celgene Corporation: Employment, Equity Ownership. O'Connor:Celgene Corporation: Employment, Equity Ownership. Rose:Celgene Corporation: Employment, Equity Ownership. Beach:Celgene Corporation: Employment, Equity Ownership. OffLabel Disclosure: Durvalumab is a PD-L1 blocking antibody indicated for the treatment of patients with 1) locally advanced or metastatic urothelial carcinoma who have disease progression during or following platinum-containing chemotherapy, or who have disease progression within 12 months of neoadjuvant or adjuvant treatment with platinum-containing chemotherapy, or 2) unresectable, stage 3 NSCLC whose disease has not progressed following concurrent platinum-based chemotherapy and radiation therapy.

Description: Abstract 3480 Background: Outcomes for patients with refractory or relapsed acute myeloid leukaemia (AML) are extremely poor and allogeneic haemopoietic stem cell transplantation (HSCT) provides the best hope for prolonged disease free survival. Ablative HSCT combines high dose, anti-leukaemic chemoradiotherapy and the graft versus leukaemia (GVL) effect, but is associated with significant toxicity and mortality and these risks rise exponentially with advancing age. Several factors mitigate against an attempt to transplant patients after relapsed disease, including a low probability of achieving second remission, high re-induction mortality, prolonged cytopenias and opportunistic infections and prolonged hospitalization. Based on promising results [1], we undertook a phase II study of sequential chemotherapy immediately followed by reduced intensity conditioning (RIC)-Allo with the aim of increasing the safety and applicability of AlloHSCT, while maintaining its antileukaemic efficacy. Patients/Methods: All eligible patients received treatment with Daunorubicin 45mg/m2 OD IV D-15 to D-13 and AraC 1.5g/m2 BD IV D-15 to D-10, a three day rest period, and conditioning with Fludarabine 25mg/m2 D-6 to D-2 and Cyclophosphamide 1g/m2 D-3 and -2 before receiving HSCT. Graft versus Host Disease (GVHD) prophylaxis was with Cyclosporine and Methotrexate. To date 33 patients were enrolled (table 1), of whom 31 patients underwent transplant. Results: 28/31 (90.3%) patients engrafted (neutrophils ≥0.5 and platelets ≥ 20) at a median of 33.5 days (15-49), while 3 died between d21-51 due to sepsis. The median d30, d60 and d100 whole blood chimerism was 96% (range 4–100), 80% (range 5–100), and 76% (range 0–100) respectively. 6/31 (19.4%) developed acute GVHD; 5 grade 1–2, 1 grade 4. Chronic GVHD was documented in 8 patients, extensive GVHD in 4/8. 7 patients had CMV re-activation (no CMV disease) and 1 non-specified pneumonitis. Median time of hospitalization was 37 days (30-61). No patient has required DLI to date. 18 pts (56.25%) achieved complete remission (CR) as assessed by day 30 bone marrow (BM). 2 had

Description: Introduction: VTD is an effective regimen for patients with multiple myeloma and forms a backbone for the addition of novel agents. The MUK-six trial aimed to improve the efficacy by adding Panobinostat, a now FDA approved pan-histone deacetylase inhibitor that demonstrated synergy with proteasome inhibition and immunomodulatory agents in pre-clinical models. We have previously reported the phase 1 dose finding part which determined the MTD of panobinostat with VTD to be 20mg. Here we present the efficacy results from the recommended dose (RD) expansion phase (primary end point) and safety, tolerability data for all patients during the induction phase of the study. Methods: MUK-six was a multi-centre UK Phase I/IIa trial for patients with relapsed and relapsed/ refractory myeloma who had received between 1 and 4 prior lines of therapy. Subjects received VTD-P (bortezomib 1.3mg/2sc days 1 and 8, thalidomide 100mg daily (50mg if pre-existing neuropathy), dexamethasone 20mg days 1, 2, 8, 9 and panobinostat 20mg days 1, 3, 5, 8, 10, 12) every 3 weeks for up to 16 cycles (induction) followed by 1 year of panobinostat maintenance. Those planned for autologous stem cell transplantation (ASCT) received a minimum of 6 cycles of VTD-P. All patients treated with VTD-P received venous thrombosis prophylaxis as per institutional practice. Responses were assessed using modified IWG uniform response criteria and toxicity graded by CTCAE V4.0. Results: 46 patients were treated at the RD and were of a median age of 60 years (41-76). 80.4% had received one prior line of therapy (range 1-4), 71.7% had prior bortezomib and 39.2% prior thalidomide. Most patients were ISS 1 (60.9%), 45.7% had adverse FISH lesions at baseline, 8.7% had 17p deletion. 6 patients remain on treatment at the time of this abstract. 51.3% of patients came off study to proceed to ASCT. The overall response rate (≥PR) for patients receiving at least one dose of panobinostat was 91.3%, ≥VGPR 45.7% (CR 6.5%, VGPR 39.1%, PR 45.7%). The ≥VGPR rate for those with standard FISH was 52.1% vs 42.9% for adverse FISH. Those treated at first relapse had higher overall responses to those treated later in their disease course (≥PR 94.6% vs 77.8%). Responses were independent of prior bortezomib exposure (≥PR 90.9%, ≥VGPR 45.5% vs PR≥92.3%, ≥VGPR 46.2%). Treatment was generally well tolerated, with a mean panobinostat dose of 17.4mg (86.8% of the RD) delivered across all cycles. 32.1% of those starting at 50mg thalidomide stopped the drug due to toxicity, and 52.6% of those starting at 100mg required dose reductions/stopping. 46 serious adverse events were reported in 27 patients which were mainly infections (17/46, 37.0%). The commonest grade 3-4 toxicities reported for all 57 patients were: neutropenia (14, 24.6%), hypophosphatemia (11, 19.3%), thrombocytopenia (8, 14.1%) and diarrhoea (6, 10.5%). Of note there were no reports of ≥ grade 3 neuropathy. The most frequent grade 1-2 toxicities were fatigue (50, 87.7%), neuropathy (43, 75.5%), constipation (35, 61.4%), diarrhoea (35, 61.4%), bone pain (33, 57.9%), and nausea (27, 47.4%). 2 patients withdrew consent due to toxicity. Conclusions: This study demonstrated that panobinostat can be safely given in combination with VTD and appears highly effective with a response rate of 91.3%, ≥VGPR 45.6% despite 72% having previous bortezomib. This regimen was well tolerated, in particular the incidence of diarrhoea, neuropathy and asthenia/fatigue appeared lower than that observed in the PANORAMA 2 trial (San Miguel et al., 2014). It is possible that the incorporation of a low intensity subcutaneous bortezomib schedule (2 doses every 3 weeks) contributed to the lesser toxicity. Acknowledgments: This trial was part of the Myeloma UK Clinical Trial Network, ISRCTN: 59395590. Disclosures Popat: Janssen: Honoraria. Off Label Use: Panobinostat: use outside of FDA licence, not yet EU approved. Kishore:Celgene: Other: Conference Sponsorship; Jazz pharma: Other: Conference Sponsorship. Oakervee:Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Yong:Janssen: Honoraria; Autolous: Consultancy; Amgen: Honoraria; BMS: Honoraria; Takeda: Honoraria; Novartis: Consultancy. Cook:Sanofi: Consultancy, Honoraria, Speakers Bureau; Jazz Pharma: Consultancy, Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau; Chugai: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau. Cavenagh:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Description: Abstract 3699 Idiopathic adult TTP is an acute life threatening disorder, in which antibodies, primarily IgG, are detected against ADAMTS 13. We undertook a a phase II trial in 40 patients between 2006-09 of Rituximab, 375mg/m2, weekly for 4 weeks, within 3 days of admission of acute TTP, in conjunction with standard therapy (PEX and steroids). Results have been compared to 40 historical controls (2000-2006), who had not received Rituximab, but had received other immunosuppressive treatments. The female to male ratio was 2:1, age 42 years (21-76), compared to 42 years (15-78) in the historical group. A third of trial patients required ITU admission and 15% were intubated and ventilated at presentation. One patient was withdrawn from the trial. Pre the 2nd Rituximab infusion, 68% had a platelet count 〉50 ×109/L and 38% 〉150 ×109/L. Six cases received more than 4 Rituximab infusions (maximum of 8), primarily non-Caucasian, guided by ADAMTS 13 assays. There was a significant reduction in days admitted in hospital in the Rituximab group (median 16.5 days) compared to historic controls (median 20 days) (p=0.04, Spearman correlation), specifically in Caucasian patients (12.5 V's 16 days-Rituximab V's Historical groups) (p=0.0005 Pearson Correlation). There was no overall significant difference in the number of PEX to remission. ADAMTS 13 activity on admission was median

Description: Background: Overall survival (OS) in older patients (pts) with AML and poor-risk cytogenetics is only ~2-3 months (mos) (Burnett, Cancer, 2007). Often these pts receive only palliative treatment (Tx) with best supportive care (BSC). Low-dose Ara-C (LDAC) provides no OS benefit in pts with poor cytogenetics (Döhner, Blood, 2010). Typically, intensive chemotherapy (IC) is either not suitable for older AML pts with poor cytogenetics or, when it is used, provides no OS benefit (Kantarjian, Blood, 2010). The phase 3, multicenter, randomized, open-label AZA-AML-001 trial showed azacitidine (AZA) Tx in older pts with newly diagnosed AML (〉30% bone marrow [BM] blasts) prolonged median OS by ~4 mos vs conventional care regimens (CCR) (10.4 vs 6.5 mos; p=0.1009) and improved 1-year survival (46.5% vs 34.2%) (Dombret, EHA, 2014). Cytogenetic risk is a prognostic indicator in elderly AML and a frequent determinant of Tx approach and outcomes. Objective: To determine the effect of Tx with AZA vs CCR on OS and 1-year survival in AZA-AML-001 pt subgroups based on cytogenetic risk classification. Methods: Pts aged ≥65 years with newly diagnosed de novo or secondary AML who were ineligible for transplant, with intermediate- or poor-risk cytogenetics (pts with favorable cytogenetics were excluded from study), ECOG performance status 0-2, and WBC count ≤15x109/L, were eligible. Before randomization, each pt was preselected to receive 1 of 3 commonly used CCR for older pts with AML, per investigator choice: IC (standard 7+3 regimen), LDAC (20 mg SC BID x 10 days/28-day cycle), or BSC only. Pts were then randomized to AZA (75 mg/m2/day SC x 7 days/28-day cycle) or to CCR, in which case they received their preselected Tx. The primary endpoint was OS. Cytogenetic risk groups were assessed per NCCN criteria by central review: intermediate (INT; all cases), intermediate with normal karyotype (cytogenetic normal [CN]), and poor. Survival at 1 year was compared between Tx. Median OS for AZA vs CCR was calculated using Kaplan-Meier methods, hazard ratios (HR) and 95% confidence intervals (CI) were determined by unstratified Cox proportional hazards model, and p values by log-rank test. Results: In all, 488 pts were randomized, 241 to AZA and 247 to CCR. Cytogenetic risk was balanced between Tx groups: 315 pts had INT-risk cytogenetics (AZA n=155 [64%], CCR n=160 [65%]), including 218 who were CN (AZA n=113 [73%], CCR n=105 [66%]), and 170 pts had poor-risk cytogenetics (AZA n=85 [35%], CCR n=85 [34%]). Within each of the 3 cytogenetic risk subgroups, the distribution of pts receiving individual CCR was very consistent: ~18% of each cytogenetic risk subgroup received BSC, ~64% received LDAC, and ~18% received IC. Baseline characteristics were generally balanced among the AZA and CCR Tx arms and the 3 cytogenetic risk groups (Table). At baseline, proportionately more pts with poor-risk cytogenetics in the AZA group were aged ≥75 years (57.6% vs 47.1% with CCR) and more pts in the CCR group had AML with myelodysplastic changes (45.9% vs 37.6% with AZA). Median OS (95%CI) in poor-risk pts was significantly prolonged with AZA vs CCR: 6.4 mos (4.2, 8.1) vs 3.2 mos (2.2, 4.7), respectively; HR=0.68 (0.50, 0.94), p=0.019 (Figure). Median OS in INT-risk pts was 13.0 mos (11.2, 16.3) vs 10.1 mos (7.1, 13.3) with AZA vs CCR; HR=0.90 (0.70, 1.16), p=0.41. Median OS in the CN subgroup was 14.1 mos (12.6, 19.5) vs 10.0 mos (6.4, 13.3); HR=0.81 (0.59, 1.10), p=0.18. Estimated 1-year survival was higher with AZA vs CCR in all cytogenetic risk subgroups. Twice the proportion of AZA-treated pts in the poor-risk subgroup were alive at 1 year vs. CCR pts (30.9% vs 14.0%, respectively), a clinically meaningful difference of 16.9% (95%CI 4.4, 29.5). Similarly, in the CN subgroup, 60.7% vs 44.1% of pts were alive at 1 year in the AZA and CCR groups, a difference of 16.5% (3.2, 29.8). AZA effect on 1-year survival in the INT-risk subgroup was also favorable (55.2% vs 45.5% with CCR) (difference 9.7% [-1.4, 20.8]). Grade 3-4 hematologic adverse event rates with AZA were consistent with previous reports (Santini, Eur J Haematol, 2010), with no meaningful differences among all cytogenetic risk groups. Conclusions: Median OS in older pts with AML and poor-risk cytogenetics was meaningfully improved with AZA compared with the CCR currently used for AML, with those pts receiving AZA twice as likely to be alive at 1 year as those treated with CCR. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Döhner: Celgene: Consultancy. Off Label Use: Use of azacitidine in AML with blast count 〉30%. Seymour:Celgene: Consultancy, Honoraria, Speakers Bureau. Wierzbowska:Celgene: Honoraria, Speakers Bureau. Selleslag:Celgene: Consultancy, Research Funding, Speakers Bureau. Cavenagh:Celgene: Honoraria. Kumar:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Schuh:Celgene: Membership on an entity's Board of Directors or advisory committees. Candoni:Celgene: Consultancy, Speakers Bureau. Récher:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Sandhu:Celgene: Honoraria. Bernal del Castillo:Celgene: Consultancy. Al-Ali:Celgene: Honoraria, Research Funding. Martinelli:Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau; Pfizer: Consultancy; ARIAD: Consultancy. Falantes:Celgene: Consultancy. Stone:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees. Minden:Celgene: Honoraria. McIntyre:Celgene: Employment. Songer:Celgene: Employment, Equity Ownership. Lucy:Celgene: Employment, Equity Ownership. Beach:Celgene: Employment, Equity Ownership. Dombret:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Description: Background: AML is characterized by molecular heterogeneity; morphology and genetic alterations are important prognostic factors (Weinberg, 2009). In the large, phase 3, multicenter, randomized AZA-AML-001 study, AZA treatment (Tx) prolonged median overall survival (OS) vs CCR by ~4 months (10.4 vs 6.5 mo; p=0.1009) in older pts with newly diagnosed AML (〉30% BM blasts). About 33% of patients (pts) in AZA-AML-001 had AML with morphologic dysplastic changes (AML-MDC). Aim: Determine effects of AZA vs CCR on OS, response, and safety in the subset of pts with AML-MDC in the AZA-AML-001 trial; and further analyze OS in AML-MDC pts who had been preselected to receive low-dose cytarabine (LDAC) before randomization to AZA or CCR. Methods: Eligible pts were age ≥65 years (yrs), had AML with 〉30% BM blasts, ECOG performance status (PS) 0-2, WBC count ≤15x109/L, and intermediate- or poor-risk cytogenetics. This analysis includes pts who, based on local assessment, had AML-MDC.Before randomization, investigators preselected the preferred Tx option for each pt from 3 CCR: intensive chemotherapy (IC; standard 7 + 3 regimen), LDAC (20mg SC BID x 10 days [d]/28d cycle), or best supportive care (BSC) only. Pts were then randomized to AZA (75mg/m2/d x 7 d/28d cycle) or CCR, and then received the preselected CCR. Median OS (Kaplan-Meier method) and percent of pts alive at 1 yr were compared between AZA vs CCR for all pts with AML-MDC, and between AZA vs LDAC specifically in pts with AML-MDC preselected to LDAC before randomization. Response was assessed by IWG AML criteria (Cheson, 2003). Transfusion independence (TI) was defined as no transfusion for 56 consecutive days for transfusion dependent (TD) pts at baseline (ie, ≥1 transfusion in 56d before randomization). Overall response was defined as complete remission (CR) + morphologic CR with incomplete blood count recovery (CRi). Adverse events (AEs) were graded by NCI-CTCAE v4. Hazard ratios (HR) and 95% confidence intervals (95%CI) were determined by unstratified Cox proportional hazards model and p values from log-rank or Fisher's exact test. Results: Of 488 pts in AZA-AML-001, 158 (32.4%) had AML-MDC and are included in these analyses. Baseline characteristics were generally balanced between Tx arms (AZA n=75, CCR n=83 [IC n=13, LDAC n=50, and BSC n=20]). Median (range) ages were 76 (65, 86) and 74 (66, 87) yrs in the AZA and CCR groups, respectively. Higher proportions of pts in the AZA arm were age ≥75 yrs (59% vs 48% of CCR) and had prior MDS (47% vs 37%). In the AZA and CCR arms, 43% and 47% of pts had poor-risk cytogenetics, and 24% and 25% had ECOG PS score of 2. Median (range) %BM blasts (central review) in the AZA and CCR arms was 67% (4, 99) and 73% (9, 100). Mediannumber of Tx cycles with AZA, IC, and LDAC were 6 (1, 28), 1 (1, 3), and 3 (1, 23). Median exposure to BSC was 79 d (8, 535). Median OS in pts with AML-MDC was prolonged 2-fold with AZA vs CCR: 12.7 mo (95%CI 7.2, 14.1) vs 6.3 mo (4.3, 9.6); HR=0.69 (0.48, 0.98), p=0.0357 (Figure). Similarly, 1-yr survival was greater with AZA: 50.7% vs 33.8% with CCR (16.9% difference [95%CI 1.5, 32.2]). Rates of CR+CRi were 26.7% with AZA vs 19.3% with CCR (Table). Most pts with AML-MDC (n=99, 63%) were preselected to receive LDAC (AZA n=49, LDAC n=50). Median OS in the preselected LDAC group with AZA vs LDAC, respectively, was 13.2 mo vs 6.3 mo, a 6.8-mo improvement with AZA (HR=0.76 [95%CI 0.49, 1.19], p=0.23). Further, 1-yr survival with AZA vs LDAC was 55% vs 31% (24% difference [95%CI 5.0, 43.0]). In the overall AML-MDC group with baseline-TD, 16/51 (31%) and 14/58 (24%) attained RBC TI in the AZA and CCR groups, and 10/26 (39%) and 12/33 (36%) attained platelet TI. Grade 3-4 anemia, neutropenia, febrile neutropenia, and thrombocytopenia rates, respectively, were: AZA 12%, 30%, 30%, 28%; IC 15%, 46%, 39%, 31%; LDAC 16%, 29%, 35%, 27%; and BSC 6%, 11%, 44%, 11%. Conclusions: AZA prolonged median OS 2-fold to 〉1 yr in this older, poor-risk subgroup of pts with AML-MDC. More than one-half of AZA-treated pts with AML-MDC remained alive at 1 yr. Notably, median OS in pts preselected to LDAC, but who were randomized to AZA, was more than doubled vs pts who did receive LDAC. AZA safety profile was consistent with that seen in the entire AZA-AML-001 population (Dombret, 2014). Compared with commonly used CCR, AZA was safe, effective and well- tolerated in this subset of pts with AML. These data suggest AZA may be a beneficial initial Tx as an alternative to LDAC in pts with AML-MDC. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Seymour: Celgene: Consultancy, Honoraria, Speakers Bureau. Off Label Use: Use of azacitidine in AML with blast count 〉30%. Döhner:Celgene: Consultancy. Wierzbowska:Celgene: Honoraria, Speakers Bureau. Selleslag:Celgene: Consultancy, Research Funding, Speakers Bureau. Cavenagh:Celgene: Honoraria. Kumar:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Schuh:Celgene: Membership on an entity's Board of Directors or advisory committees. Candoni:Celgene: Consultancy, Speakers Bureau. Récher:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Sandhu:Celgene: Honoraria. Bernal del Castillo:Celgene: Consultancy. Al-Ali:Celgene: Honoraria, Research Funding. Martinelli:Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau; Pfizer: Consultancy; ARIAD: Consultancy. Falantes:Celgene: Consultancy. Stone:Agios: Consultancy; AbbVie: Consultancy; Amgen: Consultancy; Celator: Consultancy; Celgene: Consultancy; Roche: Consultancy. Minden:Celgene: Honoraria. McIntyre:Celgene: Employment. Songer:Celgene: Employment, Equity Ownership. Lucy:Celgene: Employment, Equity Ownership. Beach:Celgene: Employment, Equity Ownership. Dombret:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.