Othus, Megan

Abstract Background: Overall survival (OS) remains the definitive primary efficacy endpoint to evaluate previously untreated acute myeloid leukemia (AML) therapies, but it requires prolonged follow-up. An earlier endpoint assessed post-treatment would expedite clinical trial conduct and accelerate patient access to effective new therapies. Our objective was to formally evaluate event-free survival (EFS) as a surrogate endpoint for OS in untreated AML. Methods: Individual patient data were analyzed from 2,475 patients (pts) from 4 multicenter, randomized controlled phase III trials of active treatment in previously untreated AML using anthracycline and cytarabine induction chemotherapy as the concurrent control (CALGB 10201, n=506, enrollment period 2003-2006, age 60-88 years (y); CALGB 10603, n=717, enrollment period 2008-2015, age 18-60 y, FLT3-mutated pts only; SWOG 0106, n=595, enrollment period 2004-2009, age 18-60 y; ECOG-ACRIN 1900, n=657, enrollment period 2002-2008, age 17-60 y). Individual patient-level surrogacy examines the association between the individual patients' EFS and OS time after adjusting for treatment effect, and was assessed using the copula bivariate survival model (Kendall's tau). Trial-level surrogacy measures how precisely the treatment effect on OS can be predicted on the basis of observed treatment effect on EFS, and was evaluated using both linear regression (R2WLS) weighted by trial size and Copula bivariate (R2Copula) models. Pre-specified criteria for surrogacy required either R2WLS or R2Copula ≥0.80, neither below 0.7, with either lower bound 95% Confidence Interval (CI) >0.60. Sensitivity analyses were conducted using different EFS definitions (Table 1). Results: With a median follow-up of 50.2 months for the 896 patients still alive, the median OS and EFS across all four trials were 20.9 months (95% CI: 19.0-22.7) and 5.6 months (95% CI: 4.5-6.4), respectively. Trial-level surrogacy for EFS was strong (R2WLS=0.79; R2Copula=0.89), indicating a high correlation of treatment effect between EFS and OS. At the individual patient-level, however, EFS showed weak association with OS (tau= 0.52), compared to the strength of trial-level surrogacy. The discrepancy between patient-level EFS and OS was greatest among patients who did not achieve a CR, followed by those who achieved a CR but relapsed (Figure 1). Sensitivity analysis on alternative EFS definitions showed that the trial-level surrogacy was similar, but individual patient-level surrogacy varied across different EFS definitions (Table 1). This is consistent with what we previously reported (ASH 2016): EFS estimates differed considerably based on the definition of induction failure (IF) in a single arm setting, but this had minimal impact on the estimation of the treatment effect using EFS in randomized trials. In addition, when considering only relapse and death as events (definition 4), both individual patient- and trial-level correlations were high. Conclusions: Correlation between EFS and OS was impacted by patients not achieving CR during induction. Despite the lack of patient-level correlation, a strong correlation between hazard ratios for treatment effects was observed between EFS and OS on the trial level. Hence, it remains debatable whether EFS represents a clinical benefit in itself for patient with untreated AML considering the strong correlation in treatment effects. Further validation is needed due to the small number of trials included and the heterogeneity across trials. Acknowledgment: We gratefully acknowledge the important contributions of the late Dr. Stephen H. Petersdorf, SWOG S0106 Study Chair. Support: U10CA180821, U10CA180882, U10CA180794, U10CA180820, U10CA180888; Clinicaltrials.gov Identifiers: NCT00085124 (10201), NCT00651261 (10603), NCT01253070 (11001), NCT00085709 (SWOG S0106), and NCT00049517 (ECOG-ACRIN E1900) Disclosures Uy: Curis: Consultancy; GlycoMimetics: Consultancy. Larson:Pfizer: Consultancy, Research Funding; BristolMyers Squibb: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Ariad/Takeda: Consultancy, Research Funding.

Abstract Background: The few therapies available to treat higher-risk MDS and CMML have limited impact on outcome. We previously reported initial results of S1117, which compared overall response rates (ORRs) of azacitidine (AZA) monotherapy to AZA combined with the histone deacetylase inhibitor vorinostat (VOR), or the immunomodulator lenalidomide (LEN)( ASH 2014 LBA-5). We now report updated response data and overall survival (OS), subgroup analyses, impact of cytogenetics, and effect of treatment center volume/centers of excellence on outcome. Methods: This randomized, Phase II study (ClinTrials.gov # NCT01522976) enrolled higher-risk MDS (International Prognostic Scoring System (IPSS) Int-2 or High and/or bone marrow blasts ≥5%) and CMML adult patients (pts) with <20% blasts from 3/12-6/14 to receive AZA (75 mg/m2/d on d1-7 of a 28d cycle), AZA + LEN (10 mg/d on d1-21), or AZA + VOR (300 mg BID on d3-9). Pts continued treatment until treatment failure, defined as disease progression, relapse, significant or unresolved toxicity, or lack of response. Dose reductions occurred for grade ≥3 adverse events (per NCI CTCAE) or delayed count recovery. Cytogenetic risk groups were defined per IPSS-R. The primary endpoint was improvement in ORR, by intention to treat and reviewed centrally, of one of the combination arms vs. AZA per 2006 International Working Group MDS response criteria (complete response (CR) + partial response (PR) + hematologic improvement (HI)). OS was from study entry. MDS Centers of Excellence (MCE) were defined per MDS Foundation; center volume was defined as low (1-4 pts enrolled) or high (5-17 pts). Results: Of 277 pts, 92 received AZA, 93 AZA+LEN, and 92 AZA+VOR. Baseline characteristics, previously reported, were similar across arms. Pts received a median of 22 weeks of therapy and were followed for a median of 10 months (range: 0-30). Non-protocol defined dose modification and protocol discontinuation due to toxicity occurred more frequently in combination arms vs. AZA (p=.0014 and p=.018, respectively). Responses are now assessable in all pts (Table 1). ORR was statistically similar for combination arms vs. AZA, with a trend for longer response duration (p=.083) for combinations. Within HI, AZA+LEN pts had higher HI-n than AZA pts (16% vs. 5%, p=.031). ORR for CMML pts was significantly higher for LEN+AZA vs. AZA (63% vs. 29%, p=.04), with a trend for longer response duration for combinations (p=.06); no differences in ORR were seen for therapy-related MDS, IPSS subgroups, or transfusion-dependent pts. Allogeneic transplantation rates were similar. Median OS (Figure) for AZA:AZA+LEN:AZA+VOR was 15:18 (p=.38):17 (p=.17) months; p=.19 for combination arms vs. AZA. Median OS after failure was 7:9 (p=.6):9 (p=.05) months; p=.15 for combination arms after failure vs. AZA. For pts on therapy >6 months, there was a trend (p=.08) for higher ORR for AZA+LEN vs. AZA, though response duration was similar; median OS was 18:21 (p=.44 vs. AZA):21 months (p=.45 vs. AZA). Cytogenetic risk category distribution and ORR was similar across arms. OS (compared to Very Good/Good) was worse for Poor (HR 2.07, p=.022) and Very poor (HR 4.41, p<.001), without significant modification by treatment arm (Table 2). Compared to pts without identified cytogenetic abnormalities (abn), ORR across arms was better for pts with Chr 5 abn (OR 2.38, p=.004); OS was better for normal (HR .42, p<.001) and worse for Chr 5 abn (HR 3.1, p<.001), -7 (HR 2.69, p<.001), and 17p (HR 2.61, p<.001). While small numbers prevented definitive conclusions for treatment arm effect, combinations trended towards improving OS in Normal and Chr 5 abn only. The outcome of all pts and pts on discrete study arms treated at MCE (n=75) or high volume (n=138) sites were similar to non-MCE or low-volume sites for ORR, non-protocol defined dose modifications, dose adjustment in first 4 cycles, time to off-protocol (HR 1.2, p=.21 and HR .94, p=.64), and OS (HR .81, p=.3 and HR .77, p=.12). Conclusions: In higher-risk MDS pts, ORR and OS was similar for AZA monotherapy compared to combination arms, while for CMML pts, ORR was significantly higher with AZA+LEN. For cytogenetic subgroups, OS was worse for Chr 5 abn, -7, and 17p, and may be improved by combinations in normal or Chr 5 abn. MCE or treatment at a high volume site did not impact these effects or outcomes. Figure 1. Responses Figure 1. Responses Figure 2. Cytogenetics Figure 2. Cytogenetics Figure 3. Figure 3. Disclosures Sekeres: Celgene Corporation: Membership on an entity's Board of Directors or advisory committees. List:Celgene Corporation: Honoraria, Research Funding. Odenike:Sunesis: Membership on an entity's Board of Directors or advisory committees, Research Funding. Stone:Merck: Consultancy; Celgene: Consultancy. Gore:Celgene: Consultancy, Honoraria, Research Funding. Buckstein:Celgene: Honoraria, Research Funding. Fang:Affymetrix: Research Funding. Attar:Agios Pharmaceuticals: Employment. Erba:Ariad: Consultancy; Daiichi Sankyo: Consultancy; Sunesis: Consultancy; Pfizer: Consultancy; Novartis: Consultancy, Speakers Bureau; Pfizer: Consultancy; Incyte: Consultancy, Speakers Bureau; Incyte: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Jannsen (J&J): Other: Data Safety and Monitoring Committees ; Ariad: Consultancy; Celgene: Consultancy, Speakers Bureau; GlycoMimetics: Other: Data Safety and Monitoring Committees; Seattle Genetics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Millennium/Takeda: Research Funding; Millennium/Takeda: Research Funding; Celator: Research Funding; Celator: Research Funding; Astellas: Research Funding; Astellas: Research Funding; Sunesis: Consultancy; Daiichi Sankyo: Consultancy; GlycoMimetics: Other: Data Safety and Monitoring Committees; Jannsen (J&J): Other: Data Safety and Monitoring Committees.

Abstract Background: Higher-risk MDS and CMML comprise a spectrum of disorders associated with cytopenias, high risk of transformation to acute myeloid leukemia (AML), and truncated survival. Initial treatment with a hypomethylating agent such as azacitidine (AZA) is considered standard of care. Whether addition of the histone deacetylase inhibitor vorinostat (VOR), which acts synergistically with AZA to reactivate epigenetically silenced genes, or addition of lenalidomide (LEN), which impacts the bone marrow microenvironment, improves response rates compared to AZA monotherapy is unknown. Methods: This Phase II study (ClinTrials.gov # NCT01522976) randomized higher-risk MDS (International Prognostic Scoring System (IPSS) Int-2 or High and/or bone marrow blasts >5%) and CMML patients (pts) with <20% blasts to receive AZA (75 mg/m2/d on d1-7 of a 28d cycle), AZA + LEN (10 mg/d on d1-21), or AZA + VOR (300 mg BID on d3-9). Eligibility criteria included: >18 years (yrs), no previous allogeneic transplant, no prior treatment with any of the study drugs, and adequate organ function; therapy-related (t)MDS was allowed. Pts continued treatment until disease progression, relapse, unacceptable toxicity, or lack of response. Dose reductions occurred for unresolved grade >3 adverse events (per NCI CTCAE) or delayed count recovery. The primary endpoint was improvement in overall response rate (ORR), by intention to treat and reviewed centrally, of one of the combination arms vs. AZA monotherapy per 2006 International Working Group MDS response criteria (complete response (CR) + partial response (PR) + hematologic improvement (HI)). Relapse-free survival (RFS) was from time of response. The study had 81% power to detect a 20% improvement in ORR from 35% to 55%. Results: Of 282 pts enrolled from 3/12–6/14, 276 are included in analyses (6 ineligible pts excluded): 92 on the AZA arm, 93 on AZA+LEN, and 91 on AZA+VOR. Baseline characteristics were well-balanced across arms (Table). Pts received a median of 23 weeks of therapy: 25 of AZA; 24 of AZA+LEN; and 20 of AZA+VOR and were followed for a median of 9 months (range: 0-26). Numbers of pts with notable adverse events >grade 3 for AZA:AZA+LEN:AZA+VOR included febrile neutropenia (10:13:13); gastrointestinal disorders (4:11:23); infections (2:3:3); and rash (2:12:1). Responses were assessable in 260 pts (94%). ORR for the entire cohort was 33%: 19% CR, 1% PR, and 13% HI, with a median RFS of 7 months. ORR was similar across study arms: 36% for AZA, 37% for AZA+LEN (p=1.0 vs. AZA), and 22% for AZA+VOR (p=.07 vs. AZA). CR/PR/HI rates across arms were also similar: 23%/0%/13% for AZA; 18%/1%/17% for AZA+LEN (CR p=.47 vs. AZA); and 14%/1%/7% for AZA+VOR (CR p=.18 vs. AZA); rates of bone marrow exams to assess response were 76%, 67%, and 73%, respectively. HI-P/HI-E/HI-N rates were 21%/15%/5% for AZA, 26%/14%/15% for AZA+LEN, and 12%/8%/4% for AZA+VOR. HI-N rates were higher in AZA+LEN vs. AZA (p=.05) but otherwise were similar across arms. Median time to best response across arms was 15 weeks in AZA, 16 weeks in AZA+LEN, and 16 weeks in AZA+VOR. ORR did not vary significantly across arms in subgroup analyses for tMDS, baseline red blood cell (RBC) transfusion dependence, and by IPSS risk group. ORR for CMML pts for AZA:AZA+LEN:AZA+VOR was 33%:53%(p=.15 vs. AZA):12%(p=.41 vs. AZA). Allogeneic transplantation rates were: 7 pts on AZA, 6 on AZA+LEN, and 9 on AZA+VOR. For AZA:AZA+LEN:AZA+VOR, median RFS was: 6:8:11 months (log-rank p=.3 for combination arms vs. AZA, Figure); and for pts on therapy >6 months, it was 7:7.5:13 months (log-rank p=.11 for AZA+VOR, .74 for AZA+LEN vs. AZA). Conclusions: In higher-risk MDS pts, ORR was similar for AZA monotherapy compared to AZA-containing combination arms, though some subgroups may have benefitted from combination therapy. Differences in types of response may have resulted from differential rates of follow-up bone marrow assessments. While a non-significant signal of a DFS advantage for combination therapy was observed, longer-term outcome data are being assessed. Table Table. Figure Figure. Disclosures Sekeres: Boehringer-Ingelheim: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Off Label Use: lenalidomide, vorinostat for higher-risk MDS. List:Celgene Corporation: Consultancy. Gore:Celgene: Consultancy, Research Funding. Attar:Celgene: Consultancy. Erba:Seattle Genetics: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Research Funding; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda Pharmaceuticals International Co.: Research Funding; Astellas Pharma: Research Funding; Celgene: Honoraria, Speakers Bureau.

Abstract Introduction: APL, while highly curable in the modern era, remains a therapeutic challenge in the high-risk subset, with high rates of early mortality and relapse compared to non-high-risk APL. Recent evidence has confirmed excellent outcomes in non- high-risk APL with the combination of ATO and ATRA, and a previous pilot study had indicated the efficacy of a combination of ATO + ATRA + GO in high-risk APL. The North American Leukemia Intergroup designed a larger phase 2 study to confirm the efficacy and safety of this combination in high-risk APL. Primary Objectives: 1) assessment of 3-year event-free survival (EFS); 2) assessment of early (6 week) death rate. Methods: Adult patients with newly diagnosed high-risk APL (WBC ≥10k/uL) were eligible. Induction therapy consisted of: ATRA (45 mg/m2/day), beginning on day 1; ATO 0.15 mg/kg/day, beginning on day 10; GO 9 mg/m2on day 1. ATRA and ATO were continued until remission achieved. Patients in remission went on to receive consolidation with ATO x 2 cycles, followed by ATRA + daunorubicin x 2 cycles, followed by GO x 2 cycles. Subsequent maintenance therapy consisted of ATRA + 6-mercaptupurine + methotrexate for up to 1 year. Results: Between 2008 and 2013, 73 registered patients began protocol treatment. Median age was 46.5 years, with 52% females and 48% males. Sixty-two (85%) patients completed induction therapy as planned, and 50 patients (68%) completed all planned consolidation. Sixty-two patients (85%) achieved a documented complete response (CR). Non-responses were attributable to lack of response assessment (n=10), most commonly related to death. One patient had resistant disease. With a median follow-up of 3.3 years, the Kaplan Meier 3-year EFS estimate was 79% (95% CI 68% - 87%), which was significantly improved compared to the protocol-defined historical rate of 50% (p<0.001). The 3-year overall survival estimate was 88% (95% CI 78% to 93%). The 3-year relapse-free survival estimate was 93% (95% CI 82% to 97%). At data cut-off, there was 1 documented death during remission and no reported cases of relapse. Eight of 73 patients (11%) died within 6 weeks of treatment initiation (95% confidence interval 5-20%), at a median time of 11 days (range 3-31), which was significantly lower than the protocol defined null rate of 30% (p<0.001). The most common treatment-emergent grade 3-4 adverse events during induction included: febrile neutropenia (34%), AST/ALT elevation (12%), hypoxia/differentiation syndrome (11%), hyperglycemia (11%), headache (11%), prolonged QTc (11%). Summary: the combination of ATO + ATRA + GO was safe and effective in patients with high-risk APL, producing highly durable responses, low rates of early mortality, and comparing favorably with chemotherapy-based induction regimens in this setting. Although GO is not currently commercially available in the US, this regimen should be considered as a therapeutic option for patients with high-risk APL in the future. Support: NIH/NCI grants CA180888, CA180819, CA180820, CA180821, and in part by Wyeth Pharmaceuticals (Pfizer, Inc.) Figure Figure. Disclosures Komrokji: Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Speakers Bureau; Incyte: Consultancy. Coutre:Gilead Sciences: Consultancy, Research Funding. DeAngelo:Amgen: Consultancy; Ariad: Consultancy; Baxter: Consultancy; Novartis: Consultancy; Pfizer: Consultancy; Incyte: Consultancy; Celgene: Consultancy. Othus:Glycomimetics: Consultancy; Celgene: Consultancy.

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.

Key Points High WBC is an independent predictor of early HD in APL.