Citations

Abstract Abstract 680 Cytogenetics play an essential role in determining the prognosis of patients with AML. However, there is still no validated cytogenetics grouping scheme that specifically applies to patients undergoing allogeneic stem cell transplantation, which hampers accurate prognostication and risk stratification. We studied 821 adult patients (median age 41, range 18–74) who underwent SCT between 1999 and 2004 for AML (excluding APL) in CR1 or CR2 and who were reported to the CIBMTR from centers with >20 patients meeting study criteria. 75% of patients received a myeloablative conditioning. 496 patients had a normal karyotype. The primary cytogenetics reports were manually reviewed for 92% of the patients with an abnormal karyotype. We compared the ability of the 6 existing grouping schemes (MRC, CALGB, EORTC/GIMEMA, SWOG/ECOG, DFCI, and Monosomal Karyotype (MK) classifications) to stratify patients, using both the Akaike Information Criterion in multivariable models and the C-statistic. Among all existing schemes, the DFCI system provided a marginally superior stratification for overall and leukemia-free survival. We also built a new classification using individual cytogenetic abnormalities in a Cox model that included other significant covariates (performance status, therapy-related disease, conditioning intensity, graft source, donor match, duration of CR1, and gender match). This CIBMTR scheme (see Table), which is similar to the DFCI scheme except for the inclusion of patients with t(8;21) in the intermediate group, could stratify patients into 3 groups with similar treatment-related mortality but significantly different overall survival, leukemia-free survival, and incidence of relapse. This scheme appeared to apply to both patients in CR1 and in CR2 (see FiguresF2). This transplant-specific scheme could be adopted for prognostication purposes and to stratify patients with karyotypic abnormalities entering transplantation clinical trials. Future studies may clarify the relative outcome of patients with t(8;21) and refine this scheme with the inclusion of molecular abnormalities. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 897 Recent changes in allogeneic hematopoietic cell transplantation (HCT) including increased use of reduced-intensity conditioning, peripheral blood cells as the graft source (PB) and unrelated donors (URD) warrant re-evaluation of risk factors for acute graft-versus-host disease (aGVHD) and its impact on overall survival (OS). Risk factors for these outcomes were analyzed using more recent data from CIBMTR observational database. Methods: The cohort included adult patients ≥ 20 y transplanted from an HLA-identical sibling (SD) (n=3191) or URD (N=2370) for acute myelogenous leukemia (AML), acute lymphoid leukemia (ALL), chronic myeloid leukemia (CML), or myelodsyplastic syndrome (MDS) using a T-cell replete graft from 1999–2005. Six groups were created to evaluate the impact of conditioning [(myeloablative (MA) and reduced-intensity or non-myeloablative (RIC)], total-body irradiation (TBI) and graft source [(bone marrow (BM) or PB] as follows: MA+TBI+PB (group 1), MA+TBI+BM (group 2) MA+ no TBI+PB (group 3), MA+ no-TBI+BM (group 4), RIC+PB (group 5) and RIC+BM (group 6). Separate analyses were performed for SD and URD. IBMTR grade was used to classify aGVHD. A p-value of ≤ 0.01 was considered significant. Results: Among the SD cohort, the probability of aGVHD grade B-D and grade C-D at 100 days was 39% (95% CI, 37–41%) and 16% (95% CI, 14–17%). In multivariate analyses, non-TBI based MA regimens with a BM graft (group 4), RIC conditioning with PB (group 5) and tacrolimus plus methotrexate aGVHD prophylaxis were associated with lower odds ratio of grade B-D aGVHD (Table 1). The probability of OS was 51% (95% CI: 49–53%) at 3 y and 46% (95% CI: 44–49%) at 5 y. In multivariate analyses, grade B-D aGVHD was associated with a higher risk of death. Other independent risk factors for OS are shown in Table 2. Among the URD cohort, the probability of aGVHD grade B-D and C-D at 100 days was 59% (95%, CI 57–61%) and 32% (30-34%). In multivariate analysis, BM with MA (TBI and no TBI) or RIC conditioning (groups 2, 4 and 6) were significantly associated with lower odds ratio of grade B-D aGVHD (Table 1). Other independent risk factors included a diagnosis of CML. HCT from a 7/8 HLA-mismatched URD showed a trend for higher incidence of aGVHD (p=0.02). The probability of OS was 38% (95% CI: 35–40%) at 3 y and 33% (95% CI: 31–35%) at 5 y. In multivariate analysis, grade B-D aGVHD was associated with a higher mortality. Table 2 shows other independent risk factors for OS. Conclusion: Intensity of the conditioning regimen, TBI and the graft source has a combined effect on the risk of aGVHD. In both SD and URD cohorts, BM with MA, non-TBI regimens were associated with lower risk of aGVHD. In URD cohort, BM after a RIC also was associated with a reduced risk of aGVHD. Modulation of these risk factors is needed to reduce acute GVHD incidence and death after allogeneic transplantation. Disclosures: No relevant conflicts of interest to declare.

Abstract Introduction In 2 large phase 3 trials of patients (pts) with relapsed or refractory (R/R) CLL/SLL, single-agent ibrutinib (ibr) was superior to ofatumumab (ofa) (RESONATE; Byrd. NEJM 2013) and ibr + BR was superior to placebo + BR (HELIOS; Chanan-Khan. ASCO 2015). Both studies evaluated ibr in different pt populations with different relevant comparators (eg, ofa in pts who had relapsed following prior anti-CD20-based chemoimmunotherapy [CIT] and/or with del17p, and BR in pts eligible for CIT). In the absence of head-to-head evaluations of single-agent ibr vs BR or single-agent ibr vs ibr + BR, indirect comparisons can be used for hypothesis testing by potentially providing insights on the relative efficacy of treatments. As such, an indirect comparative analysis of data from RESONATE and HELIOS was performed. Recognizing biases inherent in cross-trial comparisons, including lack of randomization across trials and consequent differences in distributions of important confounding variables (eg, pt characteristics, prognostic factors), we used pt-level data from both studies to risk adjust for confounders using accepted multivariate statistical approaches. Methods In RESONATE, pts received 420 mg oral ibr daily until disease progression or unacceptable toxicity or intravenous ofa for up to 24 weeks. The primary end point was IRC-assessed PFS, with secondary end points of OS and ORR. In HELIOS, pts received BR (≤ 6 cycles) with either 420 mg oral ibr daily or placebo until disease progression or unacceptable toxicity. Pts with del17p were excluded. The primary end point was IRC-assessed PFS, with secondary end points of ORR and OS. Per protocol amendment in both studies, pts in comparator arms could switch to ibr upon IRC-confirmed progression. The current exploratory analysis was based on the latest available data from each trial (median time on study: RESONATE, 19 months; HELIOS, 17 months) using investigator assessments, but excluding del17p pts from RESONATE. Analyses were performed using data from both the overall CLL/SLL population and only the CLL pts. Separate multivariate Cox proportional hazards models were constructed for PFS and OS, including treatment and clinically relevant prognostic variables as covariates (age, gender, Rai staging, ECOG score, del11q status, refractory status, number of prior lines of therapy, bulky disease, IgVH status). Adjusted HRs and 95% CIs are presented vs single-agent ibr, along with predicted survival curves derived from the multivariate Cox regressions. Results RESONATE and HELIOS enrolled populations with notable differences making naïve comparison flawed. Because HELIOS enrolled only CIT-eligible pts, the trial included younger pts who had received fewer lines of therapy, as well as lower proportions of pts with purine analog refractory disease, del11q, or Rai stage 4 disease. These factors have been previously reported to influence outcomes in pts with R/R CLL/SLL and thus were included as covariates in the statistical models. Other baseline factors (gender, ECOG score, bulky disease, and IgVH status) were not notably different between the trials, but were found to impact PFS and OS and thus were included as additional covariates. In the overall CLL/SLL population, PFS and OS were comparable for single-agent ibr vs ibr + BR, and were significantly improved for single-agent ibr vs BR (Figure 1). Results for only the CLL pts were similar to those shown in Figure 1 for both PFS (ibr + BR vs single-agent ibr: 1.03 [0.61-1.75], p = 0.9042; BR vs single-agent ibr: 7.52 [4.72-11.99], p < 0.0001; single-agent ibr reduced the risk of progression/death by 87% vs BR) and OS (ibr + BR vs single-agent ibr: 1.20 [0.59-2.43], p = 0.6197; BR vs single-agent ibr: 2.24 [1.14-4.40], p = 0.0197; single-agent ibr reduced the risk of death by 55% vs BR). Conclusions The adjusted indirect comparisons reported here suggest superiority of single-agent ibr over BR for PFS and OS in patients with R/R CLL/SLL. The comparisons also suggest that the addition of BR to ibr did not improve PFS or OS compared with single-agent ibr. However, as median PFS has not been reached for either ibr arm, it is too early to draw firm conclusions. Longer follow-up in the ibr arms of these studies will be required to give an indication of whether CIT adds any benefit to ibrutinib for PFS and OS. Overall, these findings provide support for single-agent ibr as an appropriate choice for all pts with previously treated CLL/SLL. Disclosures Hillmen: Roche Pharmaceuticals: Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Gilead: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; Celgene: Research Funding; Pharmacyclics LLC, an AbbVie Company: Honoraria, Research Funding. Fraser:Janssen: Honoraria, Research Funding, Speakers Bureau; Hoffman LaRoche: Consultancy, Honoraria; Celgene: Honoraria, Research Funding. Jones:Acerta Pharma BV: Research Funding. Rule:Roche: Consultancy, Other: Travel reimbursement; J&J: Consultancy, Other: Travel reimbursement, Research Funding; Celgene: Consultancy, Other: Travel reimbursement; Gilead: Research Funding. Dilhuydy:Roche: Honoraria, Other: Travel reimbursement; Janssen: Honoraria, Other: Travel reimbursement; Mundipharma: Honoraria. Jaeger:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Cymbalista:Karyopharm: Honoraria; Roche: Honoraria; Gilead: Honoraria; Janssen: Honoraria, Research Funding. Sun:Janssen/J&J: Employment, Equity Ownership. Ninomoto:Pharmacyclics LLC, an AbbVie Company: Employment. Mahler:Janssen: Employment, Other: Travel reimbursement. Cheng:Pharmacyclics LLC, an AbbVie Company: Employment. Diels:Janssen: Employment. Clow:Pharmacyclics LLC, an AbbVie Company: Employment. Salman:Janssen/J&J: Employment, Equity Ownership. James:Pharmacyclics LLC, an AbbVie Company: Employment. Howes:Janssen/J&J: Employment, Equity Ownership.

Abstract Introduction CC-292, an oral, highly selective, small-molecule irreversible-inhibitor of Btk is under investigation for the treatment of CLL and other B-cell malignancies. This phase 1 trial investigated the safety, dose limiting toxicities (DLT), and clinical activity of CC-292 monotherapy in subjects with relapsed or refractory (R/R) CLL or non-Hodgkin's lymphoma. This interim analysis focused on the safety and clinical activity in subjects with CLL and small cell lymphocytic leukemia (SLL). Methods Eligible subjects with R/R (≥ 1 prior therapy) CLL/SLL were treated with monotherapy CC-292 in a dose-escalation study with doses ranging from 125 mg to 1000 mg QD and BID dose levels of 375 mg and 500 mg. As a maximum tolerated dose was not established, CLL patients have been enrolled in an early dose expansion cohort of 750 mg QD and preliminary recommended phase 2 dose expansion cohort at 500 mg BID. All subjects received continuous dosing in 28-day cycles until progressive disease or intolerable toxicity. Clinical activity was investigator assessed per the 2008 iwCLL criteria. Results 83 subjects with R/R CLL/SLL have been enrolled as of June 30, 2013. Baseline characteristics include median age of 67 years (34-89), 52% Rai stage 3/4 disease, median 3 prior therapies (1-12), and 34% refractory to last treatment. Poor-risk factors were present in 67% of subjects, including del11q (22%), del17p (24%), and unmutated IgVH (54%). 67% of subjects remain on study. Subjects have received a median of 6 treatment cycles (0.2-21.6). The most frequent grade 3/4 adverse events (AEs) included neutropenia (21%), thrombocytopenia (15%), pneumonia (10%), and anemia (8%). Rates of febrile neutropenia were low (4%). The most common treatment-emergent AEs (≥ 10% of subjects) were diarrhea (59.7%), fatigue (37.5%), neutropenia (26.4%), thrombocytopenia (26.4%), nausea (26.4%), pyrexia (22.2%), headache (19.4%), cough (19.4%), upper respiratory infection (16.7%), peripheral edema (15.3%), abdominal pain (15.3%), dizziness (13.9%), muscle spasms (13.9%), contusion (13.9%), anemia (12.5%), pneumonia (12.5%), sinusitis (12.5%), and urinary tract infection (11.1%). One CLL patient at the 500 mg BID dose level has experienced a drug-related adverse event of grade 4 thrombocytopenia during Cycle 1 that was assessed as a DLT. The number of patients discontinuing study treatment due to AEs was low (2.4%). Results are summarized for efficacy-evaluable patients treated at the 4 dose levels where at least a partial response (PR) was achieved (750 mg, 1000 mg, 375 mg bid and 500 mg bid) (n = 55). During cycle 1, 89% experienced a ≥ 25% increase in absolute lymphocyte count (ALC), which usually resolved with continued treatment. The table below details the best responses achieved to date. In subjects with del11q, del17p, unmutated IgVH, and no high-risk genomic factors, the PR rate was 42% (5/12), 25% (3/12), 44% (7/16), and 47% (7/15), respectively. Importantly, nodal responses were induced in the majority of subjects receiving BID dosing (375 mg: 67%; 500 mg: 62%) with an overall PR rate of 40%. When achieved, nodal responses were typically observed by cycle 2 and were sustained with continued treatment. Although the sample size is small, subjects treated at 375 mg or 500 mg BID showed continued lymph node size reduction over time from cycle 2 (mean reduction of 42% and 45%, respectively) to cycle 7 (mean reduction of 60% and 71%, respectively). Conclusion CC-292 is well tolerated as an oral daily therapy. Single-agent therapy with CC-292 is sufficient to achieve high nodal and partial response rates in relapsed/refractory CLL subjects, including those with high-risk genomic features. These results support continued development of CC-292 for the treatment of patients with CLL/SLL. Disclosures: Brown: Pharmacyclics: Consultancy; Genentech: Consultancy; Celgene: Consultancy, Research Funding; Emergent: Consultancy; Onyx: Consultancy; Sanofi Aventis: Consultancy; Vertex: Consultancy; Novartis: Consultancy; Genzyme: Research Funding. Off Label Use: The abstract shows scientific information on CC292 which is an investigational product developed by Celgene. This investigational product is not approved by any health authority for any indication. Harb:Celgene: Research Funding. Hill:Celgene: Honoraria, Research Funding. Sharman:Celgene: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; Gilead: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Cylene Pharmaceuticals: Consultancy, Research Funding; Avila Pharmaceuticals: Consultancy, Research Funding. Barr:Celgene: Consultancy. Foran:Celgene: Research Funding. Burger:Pharmalytics: Research Funding; Gilead: Research Funding. Mahadevan:Novartis: Speakers Bureau; Millennium: Speakers Bureau. Ma:Genentech: Consultancy; Abbvie: Consultancy. Barnett:Celgene: Employment, Equity Ownership. Marine:Celgene: Employment, Equity Ownership. Nava-Parada:Celgene: Employment, Equity Ownership. Azaryan:Celgene: Employment, Equity Ownership. Mei:Celgene: Employment, Equity Ownership. Kipps:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract Background: Patients (pts) with CLL/SLL that have del11q tend to have relatively short remission durations and shorter overall survival (OS) with standard chemotherapy regimens. Ibrutinib (ibr), a first-in-class, oral, once-daily inhibitor of Bruton's tyrosine kinase (BTK) is indicated by the US FDA for the treatment of pts with CLL/SLL and allows for treatment without chemotherapy. In phase 3 studies, treatment with single-agent ibr was superior to treatment with ofatumumab (ofa) in relapsed/refractory (R/R) CLL/SLL (RESONATE; Byrd, N Engl J Med 2013) or chlorambucil (clb) in treatment-naïve (TN) CLL/SLL (RESONATE-2; Burger, N Engl J Med 2015); treatment with ibr + bendamustine/rituximab (BR) was also superior to treatment with BR in R/R CLL/SLL (HELIOS; Chanan-Khan, Lancet Oncol 2016). We examined the outcome of pts in these 3 studies who did or did not have del11q to determine the impact of del11q on clinical outcomes. Methods: In RESONATE, pts with R/R CLL/SLL received ibr 420 mg/day until progressive disease (PD) or unacceptable toxicity (tox) vs ofa for up to 24 weeks (300 mg week 1, 2000 mg weekly for 7 weeks, 2000 mg every 4 weeks for 16 weeks). In RESONATE-2, pts ≥65 years of age with TN CLL/SLL (excluding del17p) received ibr 420 mg/day until PD or tox vs clb 0.5 mg/kg (up to max of 0.8 mg/kg) on days 1 and 15 of each 28-day cycle (≤12 cycles). In HELIOS, pts with R/R CLL/SLL (excluding del17p) received BR (≤6 cycles) with or without ibr 420 mg/day (starting on day 2 of cycle 1) followed by single-agent ibr or placebo continued until PD or tox. Data from pts in the 3 studies were pooled (ibr pool, comparator pool) and analyzed based on whether or not their CLL/SLL had del11q. We performed a multivariate analysis to examine for risk factors prognostic for survival (del11q del17p, age, sex, race, current Rai stage, baseline ECOG PS, number of prior therapies, cytopenias; no multiplicity adjustment). Results: A total of 1210 pts with del11q data were included in the analysis: 609 in the ibr pool (179 with del11q, 430 without del11q) vs 601 in the comparator pool (149 with del11q, 452 without del11q). Demographics and baseline characteristics were generally similar in pts regardless of del11q status; differences of more than 10% included proportions with bulky disease ≥5 cm (63% vs 49%) and unmutated IGHV (88% vs 72%) in pts with or without del11q, respectively. Median lymphadenopathy and absolute lymphocyte counts were also higher in pts with del11q. At the time of the primary analysis, median treatment durations in the ibr pool were 20.0 mo with del11q and 18.7 mo without del11q; in the comparator pool 5.3 mo with del11q and 8.5 mo without del11q. Overall, ibr-treated pts had higher overall response rate (ORR) and complete response (CR) rates and longer progression-free survival (PFS, Figure) and OS than comparator-treated pts regardless of del11q status. In the ibr pool, the presence of del11q was associated with a trend of longer PFS and OS while in the comparator pool, pts with del11q had shorter PFS (Figure, Table), as compared to pts without del11q. Results were similar when excluding pts with del17p (10% of ibr pool [6%/11% with/without del11q] and 9% of comparator pool [8%/10% with/without del11q]; Table). By multivariate analysis, in the comparator pool, del11q, male sex, >1 prior therapy, presence of cytopenias, and unmutated IGHV (in R/R only) were associated with shorter PFS. However, these differences were not found in the ibr pool. The presence of del11q did not unfavorably impact the tempo of reductions in lymphadenopathy for ibr-treated pts, but did for comparator-treated pts. Adverse events leading to discontinuation were similar in ibr- and comparator-treated pts (12% [9% vs 13% with/without del11q] vs 13% [12% vs 13% with/without del11q]). Deaths within 30 days of last dose occurred in 31 pts (5% [3% vs 6% with/without del11q]) in the ibr pool and 28 pts (5% [6% vs 4% with/without del11q]) in the comparator pool. Conclusions: Treatment with ibr was superior to comparator regardless of del11q status; the benefit of ibr was most marked for pts with CLL/SLL with del11q. Presence of del11q was associated with a trend of longer PFS and OS in ibr-treated pts and shorter PFS and lower ORR in comparator-treated pts. By multivariate analysis, presence of del11q was a prognostic factor for shorter PFS for comparator-treated pts, but not for ibr-treated pts. Disclosures Kipps: Celgene: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; Pharmacyclics, LLC, an AbbVie Company: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Speakers Bureau. Hillmen:Pharmacyclics: Research Funding; Janssen: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Gilead: Honoraria, Research Funding; Abbvie: Research Funding. Demirkan:Amgen: Consultancy. Coutre:Pharmacyclics, LLC, an AbbVie Company: Consultancy, Research Funding; AbbVie: Research Funding; Janssen: Consultancy, Research Funding. Barrientos:Gilead: Consultancy, Research Funding; Janssen: Consultancy; AbbVie: Consultancy, Research Funding. Barr:Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; AbbVie: Consultancy. O'Brien:Pharmacyclics, LLC, an AbbVie Company: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria. Fraser:Celgene: Research Funding; Janssen: Honoraria, Research Funding, Speakers Bureau. Jaeger:Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses. Cramer:Janssen-Cilag: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Novartis: Consultancy, Research Funding; GlaxoSmithKline: Research Funding; Mundipharma: Other: Travel, Accommodations, Expenses; Astellas: Other: Travel, Accommodations, Expenses; Roche: Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Gilead: Other: Travel, Accommodations, Expenses, Research Funding. Stilgenbauer:Novartis: Consultancy, Honoraria, Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Research Funding; Genzyme: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding, Speakers Bureau; Mundipharma: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria, Research Funding; Gilead: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Hoffman La-Roche: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding, Speakers Bureau; Genentech: Consultancy, Honoraria, Research Funding. Salman:Janssen Research & Development: Employment, Equity Ownership, Other: Travel, Accommodations, Expenses. Solman:Pharmacyclics LLC, an AbbVie Company: Employment, Other: Travel, Accommodations, Expenses; AbbVie: Equity Ownership. Cheng:Johnson & Johnson: Equity Ownership; AbbVie: Equity Ownership; Pharmacyclics LLC, an AbbVie Company: Employment. Phelps:Johnson & Johnson: Employment, Equity Ownership. Ninomoto:Pharmacyclics LLC, an AbbVie Company: Employment; Amgen, Inc.: Equity Ownership; AbbVie: Equity Ownership. Howes:Janssen: Employment, Other: Leadership; Johnson & Johnson: Equity Ownership. James:Pharmacyclics LLC, an AbbVie Company: Employment; AbbVie: Equity Ownership. Hallek:Gilead: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Janssen-Cilag: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Mundipharma: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; AbbVie: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; F. Hoffmann-LaRoche: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau.

Abstract Total body irradiation (TBI)-based conditioning regimens are considered the standard of care for patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic cell transplantation (HCT). However, due to concerns regarding acute and long-term toxicities, non-TBI regimens, commonly including busulfan (BU), have been increasingly explored. We performed a retrospective cohort analysis with the hypothesis that there would be equivalence of these two myeloablative approaches by reviewing outcomes for adult patients (pts), aged 18-60 years, undergoing a first, well-matched sibling, related or unrelated donor HCT in CR1 or CR2 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 2005-2014. Eight hundred nineteen pts received TBI (63% 9-12 Gy, 37% ≥13 Gy) combined with etoposide (25%) or cyclophosphamide (Cy) (75%) and 299 pts received intravenous BU combined with a second alkylator Cy (15%) or melphalan (Mel) (13%), or a nucleoside analogue fludarabine (Flu) (41%) or clofarabine (Clo)(30%). The majority of the BU-based pts were treated at the Moffitt or MD Anderson Cancer Center. The BU-based regimens were grouped together for analyses since no significant differences in basic outcomes among the different chemotherapy-only regimens were noted. Patients in the BU-containing group were older but had better performance status, took longer to achieve CR1 and longer to receive HCT; more received peripheral blood than marrow grafts, peri-HCT ATG, pre- and post HCT tyrosine kinase inhibitors ( TKI), and were treated more recently than pts in the TBI-based group (Table 1). With median follow-up of 3.6 years for the BU-based group and 5.3 years for the TBI-based group, adjusted 3 year outcomes showed treatment-related mortality (TRM) BU 19% vs. TBI 25% (p=.04); relapse BU 37% vs. TBI 28% (p=.007); disease-free survival (DFS) Bu 45% vs. TBI 48% (p=.35); and overall survival (OS) BU 57% vs. TBI 53% (p=.35) (Figures A-B). Patients in the BU group had significantly more grade II-IV acute GVHD (47% vs. 40%, p=.025), but marginally less chronic GVHD (49% vs. 55% at 3 years, p=.073). In multivariate analysis, the BU group had a significantly higher rate of acute GVHD after day 50 (RR 1.75, 95% CI 1.19-2.58, p=.004), but marginally less chronic GVHD (RR 0.83, 95% CI 0.68-1.01 p=.059) and higher risk of relapse (RR 1.46, 95% CI 1.15-1.85 p=.002) compared with TBI-based regimens. Despite the observed higher risks of acute GVHD and relapse, BU-based conditioning led to similar TRM, OS, and DFS following HCT for ALL. Table 1 Table 1. Figure Figure. Disclosures Ciurea: Spectrum Pharmaceuticals: Other: Advisory Board; Cyto-Sen Therapeutics: Equity Ownership. Seftel:Otsuka: Research Funding. Pulsipher:Medac: Other: Housing support for conference; Chimerix: Consultancy; Jazz Pharmaceutical: Consultancy; Novartis: Consultancy, Other: Study Steering Committee. Champlin:Ziopharm Oncology: Equity Ownership, Patents & Royalties; Intrexon: Equity Ownership, Patents & Royalties.

Abstract Background: Combination studies with histone deacetylase (HDAC) inhibitors plus hypomethylating agents (HMA) have suggested beneficial clinical activity in higher risk MDS and AML, though exceptions have also been reported. Pracinostat is a potent oral HDAC inhibitor selective for class I, II and IV isoforms. A pilot phase Ib study of pracinostat in combination with azacitidine (AZA) in higher risk MDS demonstrated a complete response (CR)/CR with incomplete blood count recovery (CRi) rate of 89% (Proc ASH:3821, 2012). Preliminary data on 33 patients from a multi-center, open-label, single-arm Phase II study of Pracinostat in combination with AZA in elderly AML also reported a high CR/CRi rate (ASH 2014). Herein we report the latest survival and response results for this study. Methods: Eligibility includes previously untreated AML (≥20% bone marrow blasts), age ≥65 years, unsuitable for intensive therapy due to co-morbidities and/or AML related features, and intermediate or high-risk cytogenetics. Study therapy includes pracinostat, 60 mg p.o. 3 alternate days/week for 3 weeks plus AZA, 75 mg/m2) days 1-7 or days 1-5 and 8-9 either s.c. or i.v. with cycles repeated every 28 days until progressive disease, lack of response or intolerance. The primary endpoint is CR+CRi+ morphologic leukemia free state (MLFS) per IWG criteria. Response assessments occur at the end of cycle 1 or 2 then every other cycle or when clinically indicated. A Simon 2-stage statistical design is utilized with the following assumptions: null=0.10, alternate=0.25, a=0.10, power=0.90. Stage 1 n=27 and total stage 2 n=40. Secondary endpoints include overall response rate (ORR; CR+CRi+MLFS+partial response [PR]+PRi), duration of response and overall survival. Results: Between Dec 2013 and Dec 2014, 50 patients from 15 study sites were enrolled. At this time, 50 are evaluable for efficacy. Baseline disease characteristics for all patients include: median age 75 (range 66-84); 32 de novo AML, 13 evolved from AHD, 5 were treatment-related; 28 intermediate-risk and 20 high-risk cytogenetics and 2 unknown; baseline bone marrow blast counts ranged from 20% to 89% with a median of 40%. Thirty-one patients (62%) continue to be followed for survival (range: 8.5 to 18.5 months). Median overall survival has not been reached in the overall study population and neither in patients with high-risk cytogenics or those with AML secondary to MDS or prior anti-cancer therapy. The 1-year overall survival estimate is 60%. The primary endpoint of CR +CRi +MLFS has been observed in 27/50 evaluable patients (54%) to date, including 21/50 (42%) CR. The 60-day all-cause mortality rate is 10% (5/50). Treatment emergent adverse events (TEAEs) Grade ≥3 seen in >5% of patients: febrile neutropenia 30%; thrombocytopenia 22%; neutropenia 10%; cellulitis 10%; anemia 8%; fatigue 8%; sepsis 6%, and pancytopenia 6%. TEAE's leading to study therapy discontinuation: peripheral motor neuropathy (1), parainfluenza (1), atrial fibrillation/prolonged QTc (1), subdural hematoma after a fall (1), and sepsis (3). Conclusions: Pracinostat plus AZA produces a high rate of durable responses in this AML population. Median overall survival has not been reached; 1-year overall survival is estimated at 60%. Final response data and overall survival estimates will be presented at the meeting. Disclosures Off Label Use: Azacitidine is not approved for use in acute myelogenous leukemia.. Khaled:Sequenom: Research Funding. Arellano:Cephalon Oncology: Research Funding. Butler:MEI Pharma, Inc.: Employment. Ashby:MEI Pharma, Inc.: Employment. Medeiros:Celgene: Honoraria, Research Funding; Agios Pharmaceuticals: Honoraria.

Abstract Abstract 4217 Background: AHCT improves survival (OS) in newly diagnosed MM patients (pts) in large randomized trials. These trials have limited eligibility to younger, healthier pts. Selection of older pts and those with co-morbid illness for AHCT is problematic. HCT-CI, originally developed as predictor of post-allogeneic transplant outcomes, maybe valuable in stratifying risk of transplant related mortality (TRM) risk and OS in the AHCT setting. We investigated the relative impact of HCT CI along with other patient and MM related variables on outcomes after AHCT in a large cohort of transplant recipients. Methods: Outcomes of 1156 MM pts receiving AHCT after high dose Melphalan (MEL) between 2007 and 2010 reported to the CIBMTR (Center for International Blood and Marrow Transplant Research) were analyzed. HCTCI scores and individual comorbidities were prospectively reported at time of AHCT. Median follow up of survivors was 26 month. The impact of HCTCI and other potential prognostic factors including Karnofsky performance status (KPS) on OS were studied in multivariate Cox regression models. Results: HCTCI score was 0, 1, 2, 3, >3 in 42%, 18%, 13%, 13% and 14% respectively. Most common co-morbidities included pulmonary, diabetes, obesity, psychiatric, cardiac, renal and prior solid tumor. Using consolidated HCTCI scores, patients were stratified initially into 3 risk groups – HCTCI 0 (42%) vs. HCTCI 1–2 (32%) vs. HCTCI >2 (26%). Males and Caucasians were more likely to have greater HCTCI score. Higher HCTCI was associated with lower KPS <90 (33% in HCTCI 0 cohort vs. 50% in HCTCI >2). HCTCI score >2 was associated with MEL dose reduction to 140 mg/m2 (22% vs. 10% in score 0 cohort). Cytogenetic risk and MM related factors were not correlated with HCTCI. TRM at 12 month was 2%, 2%, and 3% for 3 risk groups. With extremely few TRM events, multivariate analysis did not suggest an impact of HCTCI. OS was 95%, 92%, 92% at 1 year and 87%, 81%, 80% at 2 year, respectively. OS was inferior for HCTCI >2 cohort (RR of death 1.48, p=0.02) and HCTCI cohort 1–2 (RR 1.37, p=0.04) compared with HCTCI 0 cohort. There was no significant difference in OS between HCTCI >2 vs. HCTCI 1–2 (p=0.64). Therefore the latter 2 groups were combined as the HCTCI >0 cohort [N=667] and compared with HCTCI=0 [N=489] in multivariate models. HCTCI >0 predicted inferior OS (RR of death= 1.41, p=0.01). Other significant predictors of inferior survival were KPS <90 (RR of death 1.61, p<0.01), IgA subtype (RR 1.64, p<0.01), >1 pretransplant regimen (RR 1.47, p<0.01), resistant MM at AHCT (RR 1.78, p<0.01). Major cause of death in both groups was progressive MM. Conclusion: In clinical practice, higher HCTCI score was associated with MEL dose reduction. Mortality after AHCT is predominantly related to MM progression/relapse with low incidence of TRM. Higher HCTCI scores were independently associated with inferior OS. KPS remains an important tool for risk stratification. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 597 Back-ground: Planned upfront AHCT after initial induction improves both overall and progression free survival (OS and PFS) for patients with MM in randomized trials. However, it is unclear whether patients with less than partial response after a finite period of initial therapy should receive AHCT immediately or undergo salvage therapy to improve the level of response pre-AHCT. Methods: We addressed this question by querying the CIBMTR (Center for International Blood and Marrow Transplant Research) database. Between 1995 and 2010, 575 patients received upfront AHCT (within 12 mo of diagnosis) for MM after failing to achieve partial or complete response (PR/CR) to initial induction therapy. The 2326 patients who achieved CR/PR pre- AHCT had superior survival and were excluded (Fig 1). The study groups included: the 324 who received additional salvage chemotherapy after non-response to first line therapy (SALVAGE) and then proceeded to AHCT; and 251 who had no additional salvage chemotherapy but proceeded to AHCT immediately (NOSALVAGE). Outcomes of non-relapse mortality (NRM), relapse, PFS, and OS were compared measuring overall survival from diagnosis. Multivariate analysis using Cox proportional hazard models incorporated the following variables: age, gender, Karnofsky performance score, immunoglobulin isotype, stage, serum creatinine at diagnosis, disease status pre-AHCT, conditioning regimen, time from diagnosis to transplant, type of transplant (single/tandem), novel agents (thalidomide/bortezomib/lenalidomide), time-period of transplant and number of lines of pre-transplant therapy (= or &gt; 1 line) on outcomes. Results: Study cohorts were well balanced with respect to age, gender, Karnofsky performance status, immunoglobulin isotype, disease stage. More pts in NOSALVAGE received VAD (60% vs. 47%, p=0.002) for first line therapy and had a base-line creatinine &gt; 1.5mg/dl (27% vs. 17%, p=0.008). In the SALVAGE cohort, 245 (75%) received one, 65 (20%) two and 14 (4%) three salvage regimens. 197/245(61%), 47/65(59%), 2/14 (14%) were sensitive to 1st, 2nd and 3rd line salvage therapies prior to transplant resulting in 55% in SALVAGE achieving CR/PR pre-AHCT. In NOSALVAGE, 93% were in a minimal response or stable disease state and 7% with progressive disease. In SALVAGE, 55% received AHCT after 2004 compared with 38% in NOSALVAGE likely reflecting additional agents available for salvage. The majority of patients in either cohort (&gt;90%) received Melphalan based AHCT and a minority (&lt;20%) planned tandem AHCT. In the SALVAGE cohort, 44% had AHCT &lt;8 months after diagnosis as compared to 74% in NOSALVAGE (P&lt;0.001). Median follow-up for survivors was 61 mo and 68 mo, respectively. Six year NRM (p=1.0), relapse (p=0.2), PFS (p=0.2) or OS (p=0.5) were no different between the two cohorts). On multivariate analysis, a higher creatinine at diagnosis (&gt; 1.5 vs &lt; 1.5) predicted for higher NRM (p=0.008) and inferior OS (p=0.003), and the use of novel agents predicted for lower risk of NRM (HR = 0.37, P=0.04). Since more time elapsed between diagnosis and transplant among patients who received additional salvage chemotherapy, a left-truncated multivariate analysis was performed to reduce this potential waiting time bias. This multivariate analysis produced similar outcomes for TRM, relapse, treatment failure and OS irrespective of whether or not salvage regimens were used (Fig 2). Conclusions: In the setting of upfront AHCT, no additional benefit could be demonstrated for salvage regimens to upgrade response prior to AHCT. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3925 Introduction: CLL patients (pts) who relapse following purine-analog or bendamustine-based treatments have a poor prognosis. These pts have limited therapeutic options and novel agents with alternative mechanisms of action are needed. Several phase 1 and 2 trials in rel/ref CLL showed promising activity with escalating dose regimens of lenalidomide (LEN). In other phase II studies improved clinical responses to lenalidomide appeared to correlate with dose levels > 5mg/day. This phase 2 trial investigates the safety of LEN initiated at 3 different starting doses followed by a step-wise dose escalation as tolerated in rel/ref CLL. Methods: In this ongoing trial, eligible pts with rel/ref CLL who have received ≥ 1 prior treatment regimen containing purine-analog or bendamustine are being enrolled. The objectives of this study are to evaluate primarily the safety and secondarily the efficacy of different LEN dose regimens. Pts are randomized 1:1:1 to receive a double-blinded starting dose of 5 mg, 10 mg, or 15 mg oral LEN on days 1–28 of each 28-day cycle. In all 3 treatment arms, the dose is escalated by 5 mg increments every 28 days to reach a maximum dose of 25 mg/d, depending on tolerability. In instances of poor tolerability, dose reductions also occur in 5 mg steps. Pts are stratified by relapsed versus refractory status to their last purine-analog or bendamustine-based treatment regimen and according to age (< 65 vs ≥ 65 years). Tumor lysis syndrome (TLS) prophylaxis comprises of oral hydration and allopurinol 300 mg/day and is initiated ≥ 3 days prior to starting study drug and for a minimum of the first 3 treatment cycles. A total of 105 pts are planned for enrollment to the study. Per protocol, unblinded interim analyses were conducted by the independent Data Monitoring Committee (DMC) after 18 subjects completed 1 cycle and continue at 13-week intervals. Results: To date, 95 pts are enrolled at a median age of 64 years (range 32–81). Enrolled pts are primarily male (67%) and Caucasian (92%). Cytogenetic data are available for 73 pts; 21% have del(17p), 55% have del(13q), 25% have del(11q), and of 72 patients evaluable for trisomy 12, 11 patients (15%) tested positive. IGVH is unmutated in 77% of 77 evaluable pts and 44% of 84 evaluable pts are ZAP70-positive. Based on the Binet and Rai staging systems 9 (10%), 25 (26%) and 24 (25%) of subjects are stage A, B and C, respectively; 7 (7%), 12 (13%) and 16 (17%) subjects are low, intermediate or high-risk disease, respectively. For 2 (2%) subjects the Binet/Rai staging is currently unknown. Overall, 19 pts (20%) received prior bendamustine-containing treatment and 71 pts (75%) received prior fludarabine-based treatment. The median number of prior therapies was 3 (range 1–10). Most common hematological grade ≥ 3 AEs include neutropenia (62%) and thrombocytopenia (34%). At baseline, 19% of pts presented with grade 1–2 neutropenia. The most common non-hematological ≥ grade 3 AEs include pneumonia (13%), tumor flare (13%), and fatigue (11%). TLS was reported in 3 pts (3%): grade 1, 3, and 4. In total, 8 grade 5 events were reported, 3 of which were suspected to be related to LEN: 2 cases of pneumonia and 1 death for unknown cause. At the time of the cut-off, 59 pts (62%) have discontinued treatment. Most common reasons for treatment discontinuation include disease progression (n = 20) and AEs (n = 20). To date, 47 pts (49%) have dose escalated above their starting dose levels of which 12 patients escalated to the highest dose level (25 mg daily). 18 subjects have had no dose level reduction or escalations and 1 patient is still in the first cycle of the study. Average duration of treatment is 6.5 cycles, and median number of cycles is 4. Efficacy evaluations are completed monthly after 3 months of study drug treatment. At time of the data reporting, 5 pts were on study drug but did not reach the first assessment at cycle. For the 90 pts evaluable for response, the investigator's assessment indicates 2 pts (2%) reached CR, 36 (40%) achieved PR, 33 (37%) patients had SD, and 19 (21%) pts progressed. Conclusion: The independent DMC, as of 14 June, 2012 (N=95), recommended that accrual into all three treatment arms should continue as planned, suggesting all three starting doses were well tolerated. To date, the ORR is 42% and 49% of pts were dose escalated at least once. In this rel/ref CLL population LEN appears active, and completion of accrual will clarify the appropriate dose at which to initiate therapy. Disclosures: Wendtner: Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Mundipharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: use of lenalidomie in relapsed/refractory CLL. Hallek:Celgene Corporation: Consultancy, Honoraria, Research Funding. Hillmen:Celgene Corporation: Honoraria. Gregory:Celgene Corporation: Honoraria, Research Funding. Stilgenbauer:Celgene Corporation: Honoraria, Research Funding, Speakers Bureau. Kipps:Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Purse:Celgene Corporation: Employment, Equity Ownership. Zhang:Celgene Corporation: Employment, Equity Ownership. Mei:Celgene Corporation: Employment.