ALBERT

Description: The optimal source of donor hematopoietic stem cells (HSC) is controversial. Granulocyte colony stimulating factor (G-CSF) mobilized peripheral blood (G-PB) has replaced bone marrow (BM) as the most common allograft source in adults but is associated with donor morbidity and higher rates of chronic graft versus host disease (GVHD) compared to BM. The CXCR4 antagonist plerixafor (Px) mobilizes HSC into the PB (Px-PB) faster than G-CSF and preliminary data suggest both quantitative and qualitative differences in allograft content that may impact clinical outcomes. We sought to assess the efficacy and safety of transplanted allografts collected following mobilization with Px alone in HLA-identical sibling transplantation. This was a Phase II, two-strata, multi-center prospective trial (NCT01696461) to evaluate Px-PB allografts prior to reduced intensity conditioning (RIC) and myeloablative conditioning (MAC) based hematopoietic cell transplantation (HCT). Patients aged 18-65 years with an HLA-ID sibling donor and a hematological malignancy suitable for HCT were eligible. The primary objective was to determine the proportion of donors whose cells could be successfully mobilized and collected with a sufficient CD34+ cell dose using Px as the sole mobilizing agent. Px mobilization was considered successful if ≥ 2.0x10^6 CD34+ cells/kg recipient weight were collected in no more than two leukapheresis (LP) collections. All donors receiving Px were included in the analysis of the primary objective based on the intention-to-treat principle. Secondary objectives included the incidence of acute and chronic adverse events in donors, rates of hematopoietic engraftment, donor chimerism, rates of acute and chronic GVHD, non-relapse mortality (NRM), progression free survival (PFS) and overall survival (OS) for the recipients. From July 2013 to December 2014, 64 donor/recipient pairs were enrolled at 12 centers. Donors received Px at 240μg/kg subcutaneously 4 hours prior to LP. LP was performed processing at least 4X blood volume for up to two consecutive days (a third day was allowed for low CD34+ cell yields after 2 LP procedures) to achieve a target CD34+ cell dose of ≥ 4.0 x 10^6/kg recipient weight with a minimum goal of ≥ 2.0 x 10^6/kg. All allografts were cryopreserved. GVHD prophylaxis included cyclosporine or tacrolimus in combination with methotrexate, mycophenolate mofetil, or sirolimus. G-CSF was given routinely post HCT only to MAC recipients. Patient demographics are provided in Table 1. The median donor age was 56 years (18-65). 64% of the donors were male. Donors underwent one (23%), two (72%), or three (5%) LP procedures. 63 of 64 (98%) donors achieved the primary objective. The median total CD34+ cell dose/kg recipient weight collected within 2 days was 4.6 (0.9-9.6). Maximal donor toxicity following Px injection and LP was grades 0 (30%), 1 (52%), 2 (17%), and 3 (2%). Bloating, flatulence, abdominal pain, headache, paresthesisas, injection site reaction, and dizziness were the most commonly observed toxicities. Bone pain was not observed. The one grade 3 toxicity was a vasovagal episode felt related to LP and unlikely to Px. Toxicities typically resolved within a week of LP. The median follow up is 6.3 months. Median days to ANC (〉0.5 x10^9/L) and Platelet count (〉20 x 10^9/L) recovery were 13.5 (10-148) and 19 (1-76) after MAC and 14.5 (0-25) and 18 (0-141) after RIC, respectively. The cumulative incidence of acute GVHD grades 2-4 and 3-4 at day 100 were 47% (95% CI: 30-64) and 9% (95% CI: 2-22) after MAC and 19% (95% CI: 6-38) and 5% (95% CI: 0-18) after RIC. Probability of NRM at day 100 was 4% (95% CI: 0-13) and 0% after MAC and RIC, respectively. The probability of OS at day 100 was 97% (95% CI: 88-100) and 90% (95% CI: 78-98) after MAC and RIC, respectively. In conclusion, this is the first multi-center trial to demonstrate that as an alternative to G-CSF, Plerixafor rapidly, safely, and effectively mobilizes sufficient numbers of CD34+ cells from HLA-ID sibling donors for HCT following both RIC and MAC regimens. Engraftment was generally prompt and early results of secondary endpoints in recipients are encouraging. Longer follow-up and more extensive analysis of donor allografts and recipient outcomes will be presented at the time of the meeting. Research support was provided in part by Genzyme, a Sanofi Company. Table 1. Characteristics of recipients Table 1. Characteristics of recipients Disclosures Chen: Bayer: Consultancy, Research Funding. Devine:Genzyme: Research Funding.

Description: Relapse remains the major cause of death in older patients transplanted for AML in first complete remission (CR1) or for patients with advanced MDS at any age. Conventional myeloablative conditioning followed by allogeneic blood or marrow transplantation is associated with significantly less relapse compared with RIC when performed in younger patients with AML or MDS, but the toxicity of this approach in older patients is prohibitive. We hypothesized that pharmacokinetic targeting to optimize busulfan (Bu) exposure, combined with the administration of AZA post transplantation would mitigate the risk of relapse while avoiding non-relapse mortality (NRM) and ultimately improve progression free survival (PFS). Here we report the results of a Bu test dose strategy targeting daily Bu exposure as determined by the area under the plasma concentration versus time curve (AUC). The primary endpoint of the study was two year progression free survival (PFS). An important secondary objective was to determine whether administration of a test dose of Bu with post test sampling would enable achievement of a daily target Bu AUC level of 4000 uM*min in at least 80% of the recipients. We used this strategy as part of a RIC regimen on a prospective multi-center phase II trial conducted by the Alliance (formerly Cancer and Leukemia Group B (CALGB)). Eligibility included patients with AML in CR1 aged 60-74 years inclusive, MDS with IPSS risk 〉 Int-2 with less than 10% marrow blasts and age

Description: The Blood and Marrow Transplant Clinical Trials Network conducted 2 parallel multicenter phase 2 trials for individuals with leukemia or lymphoma and no suitable related donor. Reduced intensity conditioning (RIC) was used with either unrelated double umbilical cord blood (dUCB) or HLA-haploidentical related donor bone marrow (Haplo-marrow) transplantation. For both trials, the transplantation conditioning regimen incorporated cyclophosphamide, fludarabine, and 200 cGy of total body irradiation. The 1-year probabilities of overall and progression-free survival were 54% and 46%, respectively, after dUCB transplantation (n = 50) and 62% and 48%, respectively, after Haplo-marrow transplantation (n = 50). The day +56 cumulative incidence of neutrophil recovery was 94% after dUCB and 96% after Haplo-marrow transplantation. The 100-day cumulative incidence of grade II-IV acute GVHD was 40% after dUCB and 32% after Haplo-marrow transplantation. The 1-year cumulative incidences of nonrelapse mortality and relapse after dUCB transplantation were 24% and 31%, respectively, with corresponding results of 7% and 45%, respectively, after Haplo-marrow transplantation. These multicenter studies confirm the utility of dUCB and Haplo-marrow as alternative donor sources and set the stage for a multicenter randomized clinical trial to assess the relative efficacy of these 2 strategies. The trials are registered at www.clinicaltrials.gov under NCT00864227 (BMT CTN 0604) and NCT00849147 (BMT CTN 0603).

Description: Background: Donor grafts with more naive T cells and plasmacytoid dendritic cells were associated with improved overall survival after unrelated donor bone marrow, but not peripheral blood stem cell (PBSC) transplants (Waller, E JCO 2014). Here we present results on influence of innate and adaptive immune subsets in G-CSF mobilized allografts on incidence of acute GVHD (aGVHD) and chronic GVHD (cGVHD) in 238 patients (pts). Methods: We analyzed the absolute numbers and percentages of T, NK, NKT and B cells along with an extensive immunophenotypic characterization of their activation status in consecutive PBSC allografts obtained from sibling and unrelated donors between 2010 - 2014 and studied their association with the incidence of aGVHD and cGVHD. Wilcoxon rank sum tests were used to screen differential marker expression between those who did vs. did not develop aGVHD and similarly for cGVHD. Significant markers were evaluated in the multivariable (m.v.) setting along with known prognostic factors, including: recipient age, related vs. unrelated donor, female donor vs. not, Anti-thymocyte globulin (ATG) use (yes vs. no), and Reduced-intensity conditioning (RIC) vs. not. Cutpoints for markers were generated using recursive partitioning algorithms and evaluated in m.v. models. Results: Of the 238 alloSCT pts evaluated, most (71%) had unrelated donors, 64% received ATG, where most pts with unrelated donors received ATG (83%), and 78% received RIC. The incidence of aGVHD and cGVHD was 58% and 38% respectively. A total of 107 pts had grade II-IV aGVHD reported (71 II, 28 III, 8 IV), and 92 of 192 evaluable for cGVHD (at least 100 days of f/u) had reported cGVHD. Median follow-up in living pts was 21 months (range: 1.4 to 41.1 months). Table 1 shows dichotomized markers most influential on aGVHD. Higher absolute numbers of T cells, activated T cells, CD8+ cells, CD8+ cells expressing IL-7 receptor and CD27 were associated with higher incidence of aGVHD. Higher number of Stage 4 NK cells expressing stem cell factor receptor, and T-regs were associated with a lower incidence of aGVHD. Similar analyses were done for cGVHD (Table 2). Higher absolute numbers of activated T lymphocytes, activated B lymphocytes, KIR expressing CD3+ cells, CD8+ lymphocytes and activated NK cells were associated with higher incidence of cGVHD. When the percent of these makers in relation to total lymphocytes was evaluated regarding association with aGVHD, higher percent of T-regs (OR: 0.204, p=0.0018), effector memory T cells (OR: 0.45, p=0.024) and NKG2D positive NK cells (OR: 0.38, p=0.0008) conferred protection from aGVHD . Similar analysis for cGVHD showed higher percent of naïve CD4+ T cells conferred protection from cGVHD (OR: 0.44; p=0.0062) while higher percent of CD8+ cells (OR: 3.93; p=0.0032) and activated NK cells (OR: 2.08; p=0.024) was associated with cGVHD. Conclusions: These results show a protective role of donor T-regs, CD4+ T cells and Stage 4 NK cells from aGVHD. Additionally, higher content of activated T cells, CD8+ cells and B lymphocytes are associated with higher incidence of cGVHD. Higher content of activated NK cells seems to protect from aGVHD, but not from cGVHD. Updated results including multivariable analyses will be presented. These findings showing the influence of specific subsets in the allograft on aGVHD and cGVHD may provide opportunities for therapeutic interventions for graft engineering or pharmacologic methods for targeting specific immune subsets to decrease incidence of aGVHD and cGVHD. Table 1 Univariate model results for aGVHD with dichotomized markers using cutpoints: Marker Absolute OR p-value CD3+/CD5616- (T lymphocytes) 3.07 0.0013 CD3+/HLA DR+ (Activated T lymphocytes) 3.26 0.012 CD8+/CD45RA- (CD 8+ lymphocytes) 2.56 0.012 CD8+/CD27+ (Effector Memory CD8 cells) 3.25 0.0082 CD8+/CD127+ ( CD8 cells expressing IL-7 receptor) 2.92 0.073 CD4+/CD25+/CD127-(T regs) 0.43 0.057 CD3-/CD16-/CD56+/CD117+ (Stage 4 NK cells expressing Stem cell factor receptor) 0.12 0.0007 Table 2 Univariate model results for cGVHD with dichotomized markers using cutpoints: Marker Absolute OR p-value CD3+/HLA DR+ (Activated T lymphocytes) 4.41

Description: Abstract 3113 Background: Pre-transplantation FDG-PET/CT (PET/CT) has been associated with progression-free survival (PFS) and overall survival (OS) in patients (pts) with relapsed Hodgkin's and diffuse large B-cell lymphoma (Spaepan, Blood.102 :53-59, 2003). However, no data exist regarding the role of PET/CT pre-transplant in pts with mantle cell lymphoma (MCL). We performed a retrospective analysis of pts with MCL and available pre-transplant PET/CT to evaluate the association of pre-transplant PET/CT findings with PFS and OS. Methods: PET/CT was reviewed by a single radiologist according to International Harmonization Committee (IHC) criteria with mediastinal blood pool as the referenced background activity and also utilizing liver blood pool. Bone marrow (BM) uptake was not utilized in the PET/CT response assessment. Associations between PET/CT positivity and clinical characteristics were performed using Fisher's Exact and Wilcoxon rank sum tests. PFS curves were constructed from date of transplant until date of relapse or death by the Kaplan-Meier method and evaluated by the log-rank test. Univariable proportional hazards models described the relationship between clinical variables and PFS. Results: Twenty-nine pts with PET/CT prior to autologous stem cell transplant were included. Median age was 60 (range 37–73), and 86% were male. Median MIPI was 5.9 (range 4.9–7.0), with 36%, 40%, and 24% of pts classified as low (〈 5.7), intermediate (5.7–6.2), or high risk (〉 6.2), respectively. At diagnosis, 93% of pts had BM involvement, 56% had splenomegaly, and 27% had bulky adenopathy ≥ 5cm. Sixty-nine percent of pts were induced with RCHOP and methotrexate (RCHOP+M, Damon, JCO 27 :6101–6108); other therapies included RCHOP (n=4), RHyperCVAD (n=2), bortezomib (n=2), and REPOCH (n=1). Sixty-six percent, 21%, and 14% of pts received 2, 3–5, or 6 induction cycles prior to transplant, respectively. Conditioning regimens were BEAM (59%) and BEC (41%) and 90% of pts underwent transplant in first remission. Median time to transplant from diagnosis was 5.4 months (range 3.4–82). With a median follow up of 18 months (range 0.7–43), estimated median PFS is 42 months (95% CI 15–45). There have been 7 relapses (4 RCHOP, 1 RCHOP+M, 1 bortezomib, 1 REPOCH) and 5 deaths (disease progression, n=3, and pneumonia, n=2). Seventeen pts (59%) had a negative PET/CT prior to transplant, with identical results using mediastinal or liver blood pool. In 19, 6, and 4 pts respectively receiving 2, 3–5, and 6 cycles of induction therapy, 58%, 50%, and 75% were PET/CT negative prior to transplant. PET/CT positive pts received RCHOP+M (n=10), RCHOP (n=1), and bortezomib (n=1), Compared to PET/CT negative pts, PET/CT positive pts were younger (median age 55 v. 62, p=0.04) with lower MIPI (p=0.05). There was no significant association of bulky adenopathy (p=0.09), induction with RCHOP+M (p=0.23), or number of induction cycles (p=0.87) with PET/CT findings. 5 pts had a positive pre-transplant BM biopsy, of which 2 were BM negative by PET/CT. BM positivity on pre-transplant PET/CT was observed in 14 pts with only 3 also positive by BM biopsy. Median PFS was 45 months (95% CI 13–45) for PET/CT negative pts and 33 months (95% CI 3–33) in PET/CT positive pts (Figure 1; p=0.03). At this time, 4 of 17 PET/CT negative pts have progressed or died compared to 5 of 12 PET/CT positive pts. Of the 5 deaths experienced thus far, 4 have occurred in PET/CT positive pts. Presence of bulky adenopathy ≥ 5cm was also associated with a worse PFS (p=0.01), but MIPI (p=0.31) and age (p=0.61) were not. Conclusions: PET/CT associates with PFS after autologous stem cell transplantation in MCL (p=0.03). However, additional follow-up is needed to see if this association between PET/CT positivity and early relapse in MCL persists. In addition, as the majority of pts had 2 cycles of induction therapy with RCHOP+M, the impact of treatment regimen and number of cycles is difficult to assess in this series. Interestingly, neither age nor MIPI were associated with PFS from transplant, perhaps indicating that clinical characteristics at diagnosis are less important in pts that achieve a complete response by IHC criteria prior to transplant. Prospective investigation with centrally reviewed PET/CT scans compared with standard CT is required to determine the predictive role of pre-transplant PET/CT in MCL. Disclosures: No relevant conflicts of interest to declare.

Description: Interactions between stromal derived factor-1 (SDF-1 or CXCL12), and its receptor CXCR4 regulate hematopoietic stem and progenitor cell retention in the bone marrow. AMD3100, a bicyclam molecule that selectively blocks the interaction between CXCL12 and CXCR4, has recently been used in clinical trials to rapidly mobilize hematopoietic progenitor cells. However, the functional properties of human stem and progenitor cells mobilized with this agent are not well characterized. Here, we directly compared the NOD/SCID repopulating function of CD34+ cells rapidly mobilized (4 hours) by AMD3100 versus CD34+ cells mobilized after 5 days of G-CSF treatment. A total of 7 HLA-matched sibling donors were leukapheresed after a single injection of 240ug/kg AMD3100. After 1 week of drug clearance, the same donor was mobilized with G-CSF, allowing a paired comparison of the repopulating function of cells mobilized by the two agents. Total CD34+ cells mobilized by AMD3100 treatment averaged 1.2±0.4x106 CD34+ cells/kg (range 0.4–2.1x106 CD34+ cells/kg), as compared to G-CSF treatment at 3.2±0.9x106 CD34+ cells/kg (range 1.7–5.7 x106 CD34+ cells/kg). Leukapheresis total mononuclear cell (MNC) fraction or purified CD34+ cells (〉90% purity), were isolated and transplanted into sublethally irradiated NOD/SCID mice at varying doses. BM, spleen, and peripheral blood of mice were harvested 7–8 weeks post-transplantation and analyzed by flow cytometry for the presence or absence of engrafting human cells. Low frequency human engraftment events (

Description: Acute graft-versus-host disease (aGVHD) remains a major complication of allogeneic hematopoietic stem cell transplant (alloHSCT), underscoring the need to further elucidate its mechanisms and develop novel treatments. Based on recent observations that microRNA-155 (miR-155) is up-regulated during T-cell activation, we hypothesized that miR-155 is involved in the modulation of aGVHD. Here we show that miR-155 expression was up-regulated in T cells from mice developing aGVHD after alloHSCT. Mice receiving miR-155–deficient donor lymphocytes had markedly reduced lethal aGVHD, whereas lethal aGVHD developed rapidly in mice recipients of miR-155 overexpressing T cells. Blocking miR-155 expression using a synthetic anti–miR-155 after alloHSCT decreased aGVHD severity and prolonged survival in mice. Finally, miR-155 up-regulation was shown in specimens from patients with pathologic evidence of intestinal aGVHD. Altogether, our data indicate a role for miR-155 in the regulation of GVHD and point to miR-155 as a novel target for therapeutic intervention in this disease.

Description: Key Points Checkpoint blockade via anti–PD-1 mAbs was associated with a high overall response rate in relapsed Hodgkin lymphoma allo-HCT patients. Checkpoint blockade via anti–PD-1 mAbs after allo-HCT can be complicated by rapid onset of severe and treatment-refractory GVHD.

Description: Abstract 2693 Background: Aggressive B-cell NHL harboring a c-MYC rearrangement (myc+) with or without t(14;18) is associated with shortened PFS and overall survival (OS) (Savage, Blood 2009; Johnson, Blood 2009). Clinical presentation, risk-assessment, and therapies vary among pts and institutions. We reviewed pts with myc+ and double hit NHL treated at the Ohio State University (OSU) from Aug 2008-Jan 2012 to determine factors associated with prolonged PFS and OS. Methods: Pts with de-novo B-cell NHL who were myc+ by FISH break-apart probe were included. Pts with Burkitt's, follicular, and transformed NHL were excluded. Most pts were also evaluated for presence of t(14;18) by FISH, and those myc+ pts with t(14;18) were classified as double hit NHL. Response was determined by PET/CT at the completion of first-line therapy. Associations between myc+ and clinical characteristics were described. PFS and OS were defined from date of diagnosis to date of relapse or death. Univariable and multivariable Cox regression models were performed to assess relationships of selected clinical variables with PFS and OS. Results: Of 49 myc+ pts, 55% were male, and median age at diagnosis was 62 (range: 23–83). Morphologically, 30 pts had diffuse large B-cell lymphoma (DLBCL), 10 pts had B cell lymphoma unclassifiable with features intermediate between diffuse large B cell and Burkitt lymphoma (BCLU), and 9 pts had high grade NHL not otherwise specified. Twenty-eight pts had ECOG performance status ≤1, and 40 pts had stage III-IV disease. Twelve pts had bone marrow involvement, and 26 pts had bulky disease ≥5cm. IPI was ≥3 in 24 pts, and median Ki-67 was 90% (range: 45–100). Twenty-nine of 43 assessed pts (67%) were positive for t(14;18). Therapies included R-CHOP (N=17), R-EPOCH (N=17), Burkitt's-like (ie, R-HyperCVAD, R-CODOXM/IVAC, or R-CHOP with high dose methotrexate; N=11), or other (N=4). No pts underwent autologous transplant in first remission. Twenty-nine pts (59%) achieved a complete response (CR), 2 pts had a partial response, 1 pt had stable disease, 8 pts had progressive disease (PD), and 9 pts died before response assessment (5 pts after cycle 1, 3 pts after cycle 2, and 1 pt after cycle 3). With a median follow-up of 26.2 months (mos; range: 4.8–45.0), the median PFS for all pts was 16.6 mos (95%CI: 9.6 - not reached=NR), and median OS was 37.7 mos (95%CI: 15.7–NR). Median PFS was 3.9 mos for pts without CR vs. not yet reached in pts with CR (p

Description: Peripheral T-cell lymphomas (PTCL) are an uncommon and heterogeneous group of lymphoid malignancies characterized by a poor prognosis. Combination chemotherapy and autologous hematopoietic stem cell transplantation (HSCT) are not curative for majority of patients (pts) with PTCL. We evaluated the role of allogeneic (allo-) HSCT in pts with PTCL. We performed a retrospective analysis of all pts with histologically confirmed PTCL who underwent allo-HSCT between 5/1997 to 2/2007 at our institution. ALK1+ anaplastic large cell lymphoma (ALCL) were excluded from this analysis. There were 14 pts (11 male) with a median age of 43 years (range 30–52). Histology included 5 (35%) PTCL unspecified, 4 (28%) angioimmunoblastic T-cell lymphoma, 2 (14%) ALK1 negative ALCL, 2 NK/T-cell lymphoma and 1 panniculitis like T-cell lymphoma. Eight pts (57%) had chemosensitive disease (CR2=1, CR3=2, PR1=3, PR2=2); and 6 were high intermediate-high risk aaIPI. Eleven (78%) had advanced disease (stage III-IV) at transplantation. The median number of prior chemotherapy regimens was 3 (range 1–4). Two had previously undergone autologous HSCT. Median time from diagnosis to allo-HSCT was 12 months. Nine pts received graft from an HLA-identical sibling (SIB), while 5 underwent matched unrelated donor (MUD) transplantation. Stem cell source included peripheral blood (n-12) or bone marrow (n=2). Eight pts (57%) received myeloablative (MA) conditioning (BuCy=6, BuCy-VP16=2), while 6 (43%) received reduced intensity conditioning (RIC) (FluBlu). ATG was administered as part of preparative regimen in 3 RIC pts. Median number of CD34+ cells infused was 5.1× 106/Kg. GVHD prophylaxis consisted of short-course MTX with cyclosporine (n=9) or tacrolimus (n=5). Median time to neutrophil and platelet engraftment was 15 and 24 days respectively. Rates of grade II-III and III-IV acute GVHD were 42% (n=6) and 21% (n=3) respectively. 7 pts developed chronic GVHD. 2 pts died before response assessment. Among 12 evaluable pts, 8 achieved CR and 4 PR after allo-HSCT. 2 pts with refractory disease (RD) and 4 pts with PR (pre-HSCT) showed CR following allo-HSCT, while 3 pts with RD achieved PR following allo-HSCT. Day 100 TRM was 28% (n=4). Kaplan-Meier estimates of overall survival (OS) at 1 year and 2 years were 42 and 28% respectively. The corresponding estimates of progression free survival (PFS) are 28% and 28%, respectively. No patient had disease progression after 1 year. Using two-tailed Fisher’s exact test no significant difference was seen in; chemosensitive vs. chemorefractory pts, MA vs. RIC and SIB vs. MUD HSCT in terms of OS and DFS. On multiple logistic regression analysis no impact of age, LDH, stage, performance status and donor type on OS and PFS was seen. RIC had borderline significance for OS (P=0.05). Interestingly 1 patient in PR after MA allo-HSCT converted to CR with tapering immunosuppression. Immunosuppression was tapered in a second (RIC) patient at time of progression which resulted in CR. Disease relapse was heralded in two other patients with loss of full donor chimerism. In conclusion, in this limited retrospective analysis allo-HSCT provided a 28% probability of 2 year PFS in pts with advanced PTCL. Evidence of graft-versus-T-cell lymphoma effect was observed clinically. Prospective evaluation of this modality earlier in the disease course appears warranted.