Matched Unrelated Research Articles

Successful Treatment of Mature T-Cell Lymphoma with Allogeneic Stem Cell Transplantation: The Largest Multicenter Retrospective Analysis

Successful Treatment of Mature T-Cell Lymphoma with Allogeneic Stem Cell Transplantation: The Largest Multicenter Retrospective Analysis

Allogeneic Hematopoietic Cell Transplantation in Patients with Therapy-Related Myeloid Neoplasm after Breast Cancer: A Study of the Chronic Malignancies Working Party of the EBMT

Introduction: Therapy-related myeloid neoplasms (t-MNs) account for about 10 to 20% of all cases of AML and MDS. Allogenic hematopoietic cell transplantation (allo-HCT) is considered as the only curative treatment in this high-risk setting. Given the rise of long-term cancer survivors, an increasing number of patients are expected to become transplant candidates. Physicians are concerned about the frailty and the risk of recurrence of primary cancer. In this retrospective registry-based study, we focused on patients with t-MN secondary to breast cancer radio- and/or chemotherapy, and collected information about the outcomes and complications after allo-HCT. Methods and results: In the EBMT registry we identified 252 female adult patients who underwent an allo-HCT between 2006 and 2016 for t-MN secondary to breast cancer treatment. Median age at transplantation was 57 years, and the median time from the breast cancer diagnosis to t-MN diagnosis and subsequent allo-HCT were 3.7 and 4.6 years, respectively. The indication for allo-HCT was AML and MDS in 77% and 23% of cases, respectively. Sixty-seven% of patients were in complete remission (CR) of their t-MN at the time of transplant. Abnormal karyotype was recorded in 40% of cases. A reduced Karnofsky performance status (KPS<90) was noted in 29% of cases, and 44% of patients presented with at least one comorbidity other than the primary malignancy. Stem cell source was peripheral blood in 89% of cases. Conditioning regimens were reduced-intensity (RIC) in 61% and myeloablative (MAC) in 39% of patients, respectively, and in vivo T-cell depletion was applied in 55% of cases. TBI was used in 18%. Thirty-nine% of donors were matched related (MRD), and 30% matched unrelated (MUD). For the breast cancer, at the time of diagnosis, 5% presented with distant metastasis and 15% were triple negative; 86% received chemotherapy and 88% radiotherapy, 72% both. Of note, at the time of transplant, 93% of patients were deemed in first CR of their breast cancer, and additional 5% were in second CR or more: data on remission status were missing for 57 of patients. Median follow-up from transplant was 20 months and for the entire cohort the 2-year overall survival (OS) was 50% (95%CI 44-56%): in univariate analysis (UVA), an abnormal karyotype, being transplanted not in CR for the hematological malignancy and a worse KPS were associated with a worse prognosis [2-year OS: 41% (28-53%) for abnormal karyotype, 52% (42-62%) for normal, p=.035; 57% (49-64%) for CR, 56% (23-88%) for untreated, 34% (23-45%) for not in CR, p=.002; 55% (47-63%) for KPS≥90, 43% (31-55%) for KPS<90, p=.05]. The 2-year relapse-free-survival (RFS) was 45% (39-52%): as observed for the OS, a detrimental effect on RFS was observed for abnormal karyotype [2-year RFS: 34% (22-46%) for abnormal, 49% (39-59%) for normal karyotype, p=.034] and not being transplanted in remission for the t-MN [52% for CR (44-59%), 44% for untreated (12-77%), 31% (20-42%) for not in CR, p=.002]. 2-year relapse incidence and NRM were 33 (27-39%) and 22% (17-27%), respectively. An abnormal karyotype was significantly associated with a higher relapse rate compared to a normal [50 (37-62%) vs 26% (17-34%), p<0.001], as did an uncontrolled t-MN at the time of transplant [27% (20-34%) for CR, 33% (3-64%) for untreated, 47% (35-59%) for not in CR, p<.001]. Patients pre-exposed to radiotherapy for breast cancer experienced a higher relapse rate compared to those who did not [35 (28-43%) vs 17% (2-33%), p=.04], while the NRM was lower [18 (12-24%) vs 38% (19-58%), p=.02]. Acute grade II-IV GVHD occurred in 26% (22-33%) of patients, and the 2-year incidence of chronic GVHD was 41% (35-47%) including 22% (17-27%) of extensive grade. Seventeen cases of breast cancer recurrence were observed, of which 13 invasive. A curative approach was adopted in 7 cases. The most frequent cause of death in the whole cohort was relapse of t-MN (36%), followed by infection (28%) and GVHD (16%): the relapse of the primary breast cancer accounted for 10 (7%) cases of death. Conclusions: Our study shows that allo-HCT can be safely performed in patients with t-MN secondary to treatment to breast cancer. A major drawback is the relapse of the primary disease which nevertheless appeared a rare event. Tight collaboration and multidisciplinary discussion between the oncologist and the hematologist are fundamental, and an adequate follow-up for the solid malignancy is essential thereafter. Figure 1 Disclosures Ganser: Novartis: Consultancy; Celgene: Consultancy. Scheid:Takeda: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Amgen: Honoraria; Janssen: Honoraria, Research Funding; BMS: Honoraria. Yakoub-Agha:Celgene: Honoraria; Novartis: Honoraria; Gilead/Kite: Honoraria, Other: travel support; Janssen: Honoraria; Jazz Pharmaceuticals: Honoraria.

Long-Term Outcomes of Allogeneic Hematopoietic Cell Transplantation in Patients with Newly Diagnosed Multiple Myeloma

Long-Term Outcomes of Allogeneic Hematopoietic Cell Transplantation in Patients with Newly Diagnosed Multiple Myeloma

Evaluating Gvhd Outcomes Using Post-Transplant Cyclophosphamide/Tacrolimus/Mycophenolate Mofetil As Gvhd Prophylaxis Compared with Methotrexate/Tacrolimus in Matched-Related and Matched-Unrelated Hematopoietic Stem Cell Transplant in Relation to the Haplo-Identical Setting: A Single Center Experience

Background: The use of post-transplant cyclophosphamide (PTCy)/tacrolimus/mycophenolate mofetil (MMF) for GVHD prophylaxis has improved outcomes in haploidentical hematopoietic cell transplantation (haplo-HCT). PTCy is now being evaluated in matched-related (MRD) and matched-unrelated (MUD) allo-HCT. Previous studies demonstrated improved GVHD-free/relapse-free survival (GRFS) when PTCy was combined with two immunosuppressive agents and PTCy has also been associated with better relapse-free survival (RFS) as demonstrated in De Jong et al 2019, though only one immunosuppressive agent was used. Currently, there is limited published data comparing outcomes using PTCy/tacrolimus/MMF to standard MRD/MUD GVHD prophylaxis of methotrexate (MTX)/tacrolimus. The importance of studying this comparison may help to improve GVHD outcomes in MRD and MUD allo-HCT. Methods: We retrospectively analyzed adult patients at USC Norris Cancer Hospital (age ≥ 19) who received allo-HCT from 2018 to 2020. The primary end-points assessed were incidence and severity of 1-year aGVHD and cGVHD. Secondary end-points included day+100 mortality, 1-year overall survival (OS), 1-year RFS, 1-year transplant-related mortality (TRM), and 1-year GRFS, defined as grade 3-4 acute GVHD, systemic therapy-requiring chronic GVHD, relapse, or death in the 1-year post-HCT period. Results: A total of 65 adult MRD and MUD allo-HCT recipients and 53 haplo-HCT patients were reviewed. Of the MRD/MUD patients evaluated, approximately 51% (n = 33) were female and 49% (n = 32) were male. The age range was 20-69 years old (median = 46), and the most common diseases included ALL (46%), AML (31%), MDS (11%), and others (i.e. lymphoma, aplastic anemia (AA), myelofibrosis) (12%). 34% (n = 22) of patients received PTCy on D+3 and D+4 with tacrolimus/MMF/ on D+5 as GVHD prophylaxis and 66% (n = 43) of patients received MTX/tacrolimus on D+1, +3, +6, and +11 as GVHD prophylaxis. All haplo-HCT patients received standard PTCy/tacrolimus/MMF. Stem cell source was primarily PBSC except in HLH and AA patients. The PTCy group had more MUD allo-HCT (64%), degree of antigen mismatch (56%), and median age of 50.5 years compared with the MTX group at 44%, 47%, and 44 years respectively. 70% in the MTX group received MAC compared with 45% in the PTCy group. The haplo group had similar demographics to the MTX group. The mean CD34 cell doses in the PTCy, MTX, and haplo groups were 4.87, 5.36, and 7.24x106 cells/kg respectively. Incidences of total GVHD, aGVHD, and aGVHD grade 3 or 4 in the PTCy group were 55%, 50%, and 4.5% respectively compared with 65%, 35%, and 7% in the MTX group, though not significant. The haplo group had 68%, 55%, and 1.9% respectively. Incidence of total cGVHD and cGVHD requiring systemic therapy in the PTCy group was 4.5% and 0% respectively compared with 30% (p = .02) and 23% (p =.01). The haplo group had 13% and 1.9% respectively. Day+100 mortality, 1-year OS, 1-year RFS, 1-year TRM, and 1-year GRFS in the PTCy group were 0%, 80%, 60%, 0%, and 64% respectively compared with 7%, 88%, 90%, 7.3%, and 59%. The haplo group had 3.8%, 86%, 89%, 14%, and 66%. In a univariate analysis, factors significantly associated with GVHD were disease status (p = .0.12) and CD34 dose (p = 0.015) and antigen mismatch (p = 0.04) was associated with increased mortality. Discussion: Our results demonstrate improved overall and extensive cGVHD outcomes in the PTCy group and thus an improvement in 1-year GRFS. Furthermore, incidence and severity of 1-year cGVHD in this group are improved when compared with previously reported outcomes. 1-year GRFS reported in De Jong et al 2019 was 45% and 1-year GRFS reported for all groups in our study is higher at 66%, 64%, and 59% for the haplo, PTCy, and MTX groups respectively. Although this was not significant, it may be clinically meaningful given the significant improvement in extensive GVHD and improvement in all other secondary end-points except 1-year OS and RFS. Furthermore, the PTCy group had a higher percentage of mismatched antigens yet demonstrated superior outcomes. 1-year OS and RFS were superior in the MTX group however this is likely due to sample size differences. The improved extensive cGVHD and GRFS outcomes observed using PTCy/tacrolimus/MMF in the MRD/MUD setting should continue to be evaluated and currently there is an ongoing prospective, randomized study to further investigate. Disclosures Yaghmour: Jazz: Consultancy, Speakers Bureau; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Consultancy, Speakers Bureau; Alexion: Consultancy, Speakers Bureau; Agios: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees.

Absence of Influence of the Pre-Transplant Immune Status of Recipients on Survivals and Gvhd after Allogeneic Stem Cell Transplantation: A Retrospective Study of 195 Cases

Introduction: While many publications have studied immune reconstitution after allogeneic stem cell transplantation (allo-SCT), data exploring whether the pre-transplant immune status (IS) of the recipients has any impact after this procedure are still lacking. Material and Methods: Since May 2017, in our department, the IS of allo-SCT recipients has been systematically investigated at the time of pre-graft check-up. Data of this monocentric retrospective study on post-allo-SCT outcomes are reported here. Information was retrieved from complete blood counts (CBC) in terms of lymphocytes (normal range [NR] 1.5-4x109/L) and monocytes (NR: 0.15-0.9 x109/L). Classical multiparameter flow cytometry and a double platform were used to assess absolute counts of lymphocyte subsets, i.e. CD3+ (NR: 0.9-1.8 x109/L), CD4+ (NR: 0.5-1.2 x109/L), CD8+ (NR: 0.3-0.7 x109/L), CD19+ (NR: 0.1-0.4 x109/L) and CD56+ (NR: 0.1-0.4 x109/L). All patients also benefited from standard serum electrophoresis allowing to appreciate their global level of immunoglobulins (Ig) (NR: 8-13.6 g/L). The impact of pre-graft immune parameters was investigated for overall (OS) and disease-free (DFS) survivals as well as acute and chronic graft-versus-host disease (GVHD) incidence. Results: Between May 2017 and December 2019, 195 consecutive adults were checked for immune status before allo-SCT. They were 117 males and 78 females at a median age of 59 years-old (range: 23-71). The median follow-up for the whole cohort was 21.7 months (range: 5.77-37.5). The majority of patients had a myeloid disease (n=141) and received a reduced intensity (RIC) regimen (n=149, myeloablative [MAC] n=23; sequential n=23). The disease-risk index was low/intermediate and high/very-high for respectively 91 and 104 patients. GVHD prophylaxis included anti-thymocytes globulins (ATG) for 102, post-transplant cyclophosphamide (PTCy) for 54 and both ATG+PTCy for 39. Donors were siblings in 39 cases, matched-unrelated (MUD) in 86, haplo-identical in 66 and 9/10 mis-matched in 4. The IS was evaluated at a median of 20 days (range: 8-72) before allo-SCT. Except for monocytes (median: 0.48 x109/L, range: 0-26), all median immune cell populations were lower than the NR before allo-SCT: lymphocytes (0.84 x109/L, range: 0-8.4), CD3+ (0.7 x109/L, range: 0-3.5), CD4+ (0.37 x109/L, range: 0-2.37), CD8+ (0.25 x109/L, range: 0-2.56), CD19+ (0.005 x109/L, range: 0-0.56), CD56+ (0.097 x109/L, range: 0-0.77). Conversely, the Ig median level was in the NR (8.6 g/L, range: 1.4-28). The percentages of patients with immune cells and Ig above the lowest NR were as follows: lymphocytes: 14.8%, monocytes: 80%, CD3: 37.4%, CD4: 37.4%, CD8: 38.9%, CD19: 16.4%, CD56: 47.6%, Ig: 56.7%. Only 5 patients (2.5%) had a fully normal IS before transplant. Considering the whole cohort, 2-year OS and DFS were 55.6+3% and 50.4+3%, respectively, while incidences of day 100 grade 2-4 and 3-4 acute GVHD and 2-year moderate/severe chronic GVHD were 34.7%, 19.4% and 19.8%, respectively. The comparison of survivals between patients partitioned using either the median of the NR values for immune cells and Ig, showed no difference between subgroups. Similarly, IS had no impact on the incidence of acute nor chronic GVHD. Finally, no difference either was seen according to the conditioning regimen (RIC) or GVHD prophylaxis (ATG, PTCY or both). Conclusion: As expected, almost all pre-ASCT patients present with immune depression. However, pre-transplant IS does not appear to impact survival nor GVHD. This suggests that there is no need to decrease or replace immunosuppressive treatments commonly used in recipients before allo-SCT in the hope to provide better outcomes. Disclosures Touzeau: GlaxoSmithKline: Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Sanofi: Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses. Le Gouill:Roche Genentech, Janssen-Cilag and Abbvie, Celgene, Jazz pharmaceutical, Gilead-kite, Loxo, Daiichi-Sankyo and Servier: Honoraria; Loxo Oncology at Lilly: Consultancy. Moreau:Abbvie: Consultancy, Honoraria; Novartis: Honoraria; Sanofi: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene/Bristol-Myers Squibb: Consultancy, Honoraria; Takeda: Honoraria.

Impact of Donor Search Strategy for Allogeneic Hematopoietic Stem Cell Transplantation from Haploidentical or Matched Unrelated Donor for Patients Older Than 55 Years with Hematological Malignancies: Randomized Prospective Phase III Study

Impact of Donor Search Strategy for Allogeneic Hematopoietic Stem Cell Transplantation from Haploidentical or Matched Unrelated Donor for Patients Older Than 55 Years with Hematological Malignancies: Randomized Prospective Phase III Study

Post-transplant cyclophosphamide after matched sibling, unrelated and haploidentical donor transplants in patients with acute myeloid leukemia: a comparative study of the ALWP EBMT

BackgroundThe use of post-transplant cyclophosphamide (PTCy) is highly effective in preventing graft-versus-host disease (GVHD) in the haploidentical (Haplo) transplant setting and is being increasingly used in matched sibling (MSD) and matched unrelated (MUD) transplants. There is no information on the impact of donor types using homogeneous prophylaxis with PTCy.MethodsWe retrospectively compared outcomes of adult patients with acute myeloid leukemia (AML) in first complete remission (CR1) who received a first allogeneic stem cell transplantation (SCT) with PTCy as GVHD prophylaxis from MSD (n = 215), MUD (n = 235), and Haplo (n = 789) donors registered in the EBMT database between 2010 and 2017.ResultsThe median follow-up was 2 years. Haplo-SCT carried a significantly increased risk of acute grade II–IV GVHD (HR 1.6; 95% CI 1.1–2.4) and NRM (HR 2.6; 95% CI 1.5–4.5) but a lower risk of relapse (HR 0.7; 95% CI 0.5–0.9) that translated to no differences in LFS (HR 1.1; 95% CI 0.8–1.4) or GVHD/relapse-free survival (HR 1; 95% CI 0.8–1.3). Interestingly, the use of peripheral blood was associated with an increased risk of acute (HR 1.9; 95% CI 1.4–2.6) and chronic GVHD (HR 1.7; 95% CI 1.2–2.4) but a lower risk of relapse (HR 0.7; 95% CI 0.5–0.9).ConclusionsThe use of PTCy in patients with AML in CR1 receiving SCT from MSD, MUD, and Haplo is safe and effective. Haplo-SCT had increased risk of acute GVHD and NRM and lower relapse incidence but no significant difference in survival.

Comparison of Matched Sibling, Unrelated and Haploidentical Donor Transplants Using Post-Transplant Cyclophosphamide in Patients with Acute Myeloid Leukemia, a Study of the ALWP EBMT

Introduction The use of post-transplant cyclophosphamide (PTCy) is highly effective in preventing graft-versus-host disease (GVHD) in the haploidentical (Haplo) transplant setting and is being increasingly used in matched sibling (MSD) and matched unrelated (MUD) transplants. There is no information on the impact of donor types using homogeneous prophylaxis with PTCy. Methods We retrospectively analysed outcomes of adult patients with acute myeloid leukemia (AML) in first complete remission (CR1) that received a first allogeneic stem cell transplantation (SCT) with PTCy as GVHD prophylaxis from MSD (n=215), MUD (n=235) and Haplo (n=789) donors registered in the EBMT database between 2010 and 2017. The median follow up period of the entire cohort was 2 years. Results Median age of patients was 52 years (range, 18-76), 693 (56%) were male and 928 (78%) were CMV seropositive. 47 (6%),543 (66%) and 239 (29%) had standard, intermediate and high risk cytogenetics, respectively. Peripheral blood (PB) was used in 814 (66%) patients and myeloablative conditioning (MAC) in 739 (59%). Compared to MSD and MUD, Haplo patients were older (p Conclusions The use of PTCy in patients with AML in CR1 receiving SCT from MSD, MUD and Haplo is safe and effective and rates of GVHD are low, especially chronic. HLA mismatch in Haplo has a negative impact on acute GVHD and NRM in this setting but also offers increased anti-leukemic efficacy. As seen in other transplant scenarios, PB is associated with more GVHD and less relapse.

Type of Donor in the Setting of Allogeneic Stem Cell Transplant Does Not Significantly Affect Overall Survival in Patients with Acute Myeloid Leukemia

<h3>Background</h3> Acute myeloid leukemia (AML) remains a disease of high mortality and allogeneic hematopoietic stem cell transplant (HCT) is frequently indicated for its curative potential. However, access can be limited by availability of HLA-matched donors, comorbidities, and performance status. Recently, half-match (haploidentical) donors and reduced-intensity conditioning (RIC) have increasingly been used to alleviate limitations. The objective of this study is to compare outcomes between different types of donors (matched-sibling (MSD) vs matched-unrelated (MUD) vs haploidentical (HI) and to investigate the role of conditioning for patients with AML. <h3>Methods</h3> In this single-center retrospective study, 253 AML patients receiving first allo-HCT between 2013-2018 were included. Baseline characteristics were collected and the primary outcome of overall survival was evaluated with Kaplan Meier survival analysis and hazard ratios using cox regression models. Baseline difference between these groups were significant for mean age of donor [53.0 years (MSD), 34.8 (HI), 27.8 (MUD); p<0.01], conditioning type [53% myeloablative (MSD), 13% (HI), 45% (MUD); p<0.01], and gender of donor [84% male (MUD), 64% (HI), 57% (MSD); p<0.01]. <h3>Results</h3> Two-year survival amongst groups stratified by type of donor was not significantly different with 44.0% for MSD (95% CI: 30.4 to 57.6), 53.8% for MUD (95% CI: 44.4 to 63.2), and 53.5% for HI (95% CI: 38.6 to 70.0). When patients were stratified by conditioning type, differences in overall survival were also not statistically significant. <h3>Conclusion</h3> In this cohort of adult patients with AML, receiving an allo-HCT. Overall survival outcomes were not different between different donor types. This data is consistent with other recent reports demonstrating similar outcomes with haploidentical transplants when compared to matched-donor transplant.

Post-Transplant Cyclophosphamide after Matched Sibling, Unrelated and Haploidentical Donor Transplants in Patients with Acute Myeloid Leukemia, a Comparative Study of the ALWP EBMT

Introduction: The use of post-transplant cyclophosphamide (PTCy) is highly effective in preventing graft-versus-host disease (GVHD) in the haploidentical (Haplo) transplant setting and is being increasingly used in matched sibling (MSD) and matched unrelated (MUD) transplants. Although PTCy-Haplo has been compared with different transplant platforms, there is no information on the impact of donor types using homogeneous prophylaxis with PTCy. Methods:We retrospectively analysed outcomes of adult patients with acute myeloid leukemia (AML) in first complete remission (CR1) that received a first allogeneic stem cell transplantation (SCT) with PTCy as GVHD prophylaxis from MSD (n=215), MUD (n=235) and Haplo (n=789) donors registered in the EBMT database between 2010 and 2017. The median follow up period of the entire cohort was 2 years. Results: Median age of patients was 52 years (range, 18-76), 693 (56%) were male and 928 (78%) were CMV seropositive. AML was de novo in 1,046 (84%) patients, while 47 (6%),543 (66%) and 239 (29%) had standard, intermediate and high risk cytogenetics, respectively. Peripheral blood (PB) was used as the stem cell source in 814 (66%) patients. Regarding conditioning, 962 (78%) were chemotherapy based regimens and 500 (41%) patients received reduced intensity conditioning (RIC). Preferred conditioning regimens were thiotepa, busulfan, fludarabine for Haplo (n= 371; 47%) and busulfan, fludarabine for MSD (n= 83; 39%) and MUD (n= 102; 43%). Patients received a variety of PTCy containing immune suppressive regimens, the most frequently used being PTCy, calcineurin inhibitor and mycophenolate mofetil in Haplo (n= 684; 87%) and PTCy and calcineurin inhibitor alone in MSD (n= 52; 24%) and MUD (n= 74; 31%). In-vivo T-cell depletion (TCD) was used in 164 (13%) patients. Compared to MSD and MUD, Haplo patients were older and less frequently received RIC, TCD and PB but the distribution of cytogenetic risk group was similar between the donor types. Cumulative incidence of neutrophil recovery at 60 days was 95% (95% CI 94-96). The cumulative incidence of 100 day acute GVHD grade II-IV and III-IV, and 2-year chronic and chronic extensive GVHD were 25% (95% CI 23-28), 9% (95% CI 7-10), 31% (95% CI 28-34) and 12% (95% CI 10-14), respectively. At 2 years, the cumulative incidence of relapse and non-relapse mortality (NRM) and the probability of leukemia-free survival (LFS) and overall survival (OS) were 25% (95% CI 22-28), 19% (95% CI 17-21), 56% (95% CI 53-59) and 63% (95% CI 60-66), respectively. On multivariable analysis, outcomes were not significantly different for MSD and MUD. Haplo-SCT carried a significantly increased risk of acute grade II-IV GVHD (HR 1.6; 95% CI 1.1-2.4) but the risk was not significant for chronic GVHD (HR 1.2; 95% CI 0.8-1.8). Haplo-SCT carried a higher risk of NRM (HR 2.6; 95% CI 1.5-4.5) but a lower risk of relapse (HR 0.7; 95% CI 0.5-0.9) that translated to no change in LFS (HR 1.1; 95% CI 0.8-1.4) or GVHD/relapse-free survival (HR 1; 95% CI 0.8-1.3). The most frequent cause of death was relapse for MSD (n= 36, 53%) and MUD (n= 41, 48%) and infection for Haplo (n = 107, 39%). Interestingly, the use of PB was associated with an increased risk of acute (HR 1.9; 95% CI 1.4-2.6) and chronic GVHD (HR 1.7; 95% CI 1.2-2.4) but a lower risk of relapse (HR 0.7; 95% CI 0.5-0.9). Other variables that had an impact on LFS were: poor risk cytogenetics (HR 1.4; 95% CI 1.1-1.7), use of MAC-Chemo (HR 0.7; 95% CI 0.6-0.9), Karnofski performance status &lt;90 (HR 0.8; 95% CI 0.6-0.99), older patient age (HR 1.1 by 10 year increase; 95% CI 1.02-1.2) and CMV seropositivity of recipient (HR 1.3; 95% CI 1.0-1.6). Conclusions:The use of PTCy in patients with AML in CR1 receiving SCT from MSD, MUD and Haplo is safe and effective and rates of GVHD are low, especially chronic. HLA mismatch in Haplo has a negative impact on acute GVHD and NRM in this setting but also offers increased anti-leukemic efficacy. As seen in other transplant scenarios, PB is associated with more GVHD and less relapse. Figure Disclosures Angelucci: Novartis: Honoraria, Other: Chair Steering Committee TELESTO protocol; Celgene: Honoraria, Other: Participation in DMC; BlueBirdBio: Other: Local advisory board; Jazz Pharmaceuticals: Other: Local advisory board; Roche: Other: Local advisory board; Vertex Pharmaceuticals Incorp., and CRISPR Therapeutics: Other: Participation in DMC. Blaise:Jazz Pharmaceuticals: Honoraria; Sanofi: Honoraria; Pierre Fabre medicaments: Honoraria; Molmed: Consultancy, Honoraria. Mohty:Jazz Pharmaceuticals: Honoraria, Research Funding.

Incorporation of Posttransplant Cyclophosphamide (PCy) As Part of Standard Immunoprophylaxis (IP) for All Allogeneic Transplants: A Retrospective, Single Institution Study

Background: The incorporation of PCy in IP has allowed transplantation of stem cells from haploidentical (HI) family members such that nearly all patients have a potential donor. Thus far, HI stem cell transplantation with PCy appears to yield comparable results to matched unrelated (MUD) and matched sibling donors (MSD) who have been treated with conventional GVHD regimens, but with less chronic GVHD (cGVHD). Particularly in light of the low incidence of cGVHD, which has not been achieved with other IP strategies after T cell-replete products, PCy is being investigated after MUD and MSD transplantation where complications from cGVHD remain the major cause of non-relapse mortality. A recent study from the BMTCTN showed that in patients conditioned with reduced intensity regimens and who received MSD and MUD stem cells, the addition of PCy to standard IP (SIP) was superior to either bortezomib or maravoric in the composite endpoint of graft-versus-host disease-free, relapse-free survival (GRFS). However, this study did not include patients who received ablative conditioning regimens and did not report on the percentage of patients who were disease-free and off immunosuppression (DFOI) at 1 year after transplant. In the present study, we have compared our experience with the addition of PCy for essentially all allogeneic stem cell transplants treated over a 2 year period with the results of patients treated with SIP in the prior two year span. Outcomes of interest included one-year overall survival (OS) and one-year GRFS as well as the percentage of patients DFOI at one year. Methods: With the exception of patients receiving umbilical cord blood transplants, beginning in April 2016, all but two patients who received allogeneic transplants were given mobilized peripheral blood stem cells and then treated with PCy on days +3 and +4 followed by tacrolimus and mycophenolate on day 5. In the absence of GVHD, mycophenolate was stopped at days +35-50 and tacrolimus was tapered beginning after day +100 unless there was low donor chimerism or a suspicion of relapse in which case tacrolimus could be tapered sooner. In order to have at least one-year follow-up, the last patient included in the study was treated before April 2018. During this time period, MSD were prioritized over MUD which in turn were chosen over haploidentical donors. For comparison, we looked at the prior 2 year period (2014-2016) in which patients were treated with SIP (including ATG in patients who received MUD stem cells). Because of a higher percentage of patients with an advanced disease risk index (DRI) in the years 2014-2016, we restricted our analysis in the SIP cohort to those patients with low and intermediate risk disease but included all patients in the more recent period who received PCy. Results: There were 68 patients treated in the PCy group, including 2 patients who received PCy after HI transplants in the years 2014 and 2015. After eliminating patients with high DRI there were 40 patients in the earlier SIP cohort of patients. The resulting patient groups were similar with respect to median age (53) and diagnosis (approximately 80% of patients with AML and ALL). There was a slightly higher percentage of patients in the SIP group with hematopoietic cell transplantation-comorbidity index scores of 3 or more (52.5 vs 48.5). In the PCy group the number of patients with early, intermediate and advanced DRI were 2, 53 and 13, whereas in the (modified) SIP category 2 patients had a low DRI and 38 had intermediate DRI. In the PCy group, HI donors comprised 26.5% of the total compared to 19.1% MSD and 54.4% MUD donors. In the SIP group, MSD and MUD donors accounted for 30% and 70% of the donors. One-year percentages of OS, GRFS and DFOI were 79.4, 47.1 and 44.1 in the PCy group compared to 72, 45 and 35 in the SIP cohort. If the analysis of the PCy group is limited to the 50 patients with MSD and MUD donors (as in the SIP cohort), the one-year OS, GRFS and DFOI are 88, 52 and 52. Conclusions: PCy in combination with SIP resulted in at least comparable results as SIP despite the inclusion of 19% of patients with a high DRI and 26.5% HI donors. The results with the addition of PCy are excellent in patients with MSD and MUD donors with more than half of the patients GRFS and DFOI at one year. Future studies on GVHD prophylaxis should report DFOI as the latter status may be the best platform for posttransplant strategies aimed at eliminating minimal residual disease and for improving QOL. Disclosures No relevant conflicts of interest to declare.

Early Immune Reconstitution after Haplo-Identical Hematopoietic Stem Cell Transplantation (HCT) with Post-Transplant Cyclophosphamide (PTCY) Does Not Improve Overall Survival Compared to Matched Unrelated Donor HCT Recipients Receiving Thymoglobulin Prophylaxis (ATG)

Recent retrospective studies demonstrated similar overall survival (OS) and relapse rate after allogeneic HCT using matched unrelated or haplo-identical donors. However, differences in graft versus host disease (GVHD) prevention protocols using ATG or PTCY may have influenced the results. In addition, there is little knowledge about immune reconstitution after PTCY compared to ATG. We examined the outcomes of 73 consecutive patients who received allogeneic HCT from 5/2015 to 4/2019 (39 Haplo, 34 MUD). Patient's Characteristics shown in table-1. The two groups matched except for donor age, CD34 dose infused and race. Conditioning regimens shown in table-1. MUD recipients received GVHD prophylaxis with Tacrolimus/ Mycophenolate (Tacro/MMF) in addition to ATG (24 Patients) or PTCY (10 Patients) while Haploidentical patient received Tacro/MMF with PTCY. A panel of immune reconstitution markers collected at day 100 post- transplant for CD3, CD4, CD8, Activated T cell ( HLA- DR3+ CD3+)and NK cells ( CD56+) was obtained for 29 MUD and 28 Haploidentical recipients. We observed pronounced proliferation and recovery in all T cell subsets in Haploidentical patients compared to MUD patients at day 100 as shown in Fig-1. This robust T cell recovery in Haploidentical transplant patients with PTCY was statistically significant for CD3, CD4 and CD8. When Immune reconstitution for Haploidentical patients compared to MUD patients who received PTCY, it maintained its robust effect on T cell proliferation (Fig-2) although it did not reach statistical significance. The overall survival at one-year with median duration of follow up of 22.6 months was 61.5% and 82.3% for Haploidentical and MUD recipients respectively; P=0.14. There were 15 deaths during the first year in the Haploidentical patients (3 = relapse, 5 = severe cytokine release syndrome (CRS), 1=Veno-occlusive disease, 3= infection, 2=GVHD and 1 = primary graft failure). In contrast there were only six deaths in MUD patients (2= relapse, 3= GVHD and 1= infection). There was no deaths in MUD PTCY patients in the first year. There was no primary graft failure in either arm, however secondary graft failure occurred in 2 Haploidentical and 1 MUD patients. Median time to engraftment was 18 days for Haploidentical (range, 12-57) and 11.6 days for MUD (range, 10-18). Acute GVHD grade 2-4 developed in 35% in MUD and 23% in Haploidentical patients. Conclusions: We found robust early immune recovery after Haploidentical HCT compared to MUD HCT. The degree of HLA mismatch with Haploidentical HCT and antigen presentation may have contributed to pronounced T cell proliferation as the same effects was not observed in MUD HCT with PTCY. Despite the early recovery of T cells after Haploidentical HCT the overall survival did not exceed the overall survival with MUD HCT. Severe CRS contributed to the increased mortality seen in Haploidentical HCT patients. Further strategies are needed to decrease treatment related mortality with Haploidentical HCT. Disclosures No relevant conflicts of interest to declare.

Allogeneic Transplantation for Myelodysplastic Syndrome in Adults over 50 Years Old Using Reduced Intensity/Non-Myeloablative Conditioning: Haploidentical Relative Versus Matched Unrelated Donor

Background: Allogeneic hematopoietic cell transplantation (HCT) has been a successful strategy to treat myelodysplastic syndrome (MDS). With only approximately one-third of patients having an HLA matched sibling, most transplants use mismatched relative (haploidentical) or unrelated donors. In the current analysis we sought to study outcomes after haploidentical related compared to HLA-matched unrelated donor HCT for MDS (de novo or therapy-related). Methods: We retrospectively studied 176 recipients of haploidentical related donor and 427 recipients of 8/8 HLA-matched unrelated donor HCT in the United States between 2012 and 2017. The primary outcome was overall survival. The effect of donor type on survival and other transplant outcomes were studied using a Cox regression model. Results: Patient and disease characteristics are presented in Table 1. Most transplants (85%) were for de novo MDS in both donor groups. Although all patients received reduced intensity regimens, the predominant conditioning regimens were confounded by donor type. Total body irradiation (TBI) 200 cGy/cyclophosphamide/fludarabine (TBI/Cy/Flu; 82%) was the predominant regimen for haploidentical HCT and fludarabine with busulfan or melphalan (Flu/Bu or Flu/Mel; 79%) without in vivo T-cell depletion was the predominant regimen for unrelated donor HCT. Similarly, graft-versus-host disease (GVHD) prophylaxis was also confounded by donor type. Posttransplant cyclophosphamide/calcineurin inhibitor/mycophenolate (PT-Cy/CNI/MMF) was the prophylaxis regimen for all haploidentical transplants. CNI/MMF (31%) or CNI/methotrexate (69%) was used for unrelated donor transplants. Peripheral blood was the predominant graft for both donor types. The median follow-up was 24 months (range 3-77) after haploidentical and 36 months (range 3-74) after unrelated donor HCT. Results of multivariate analysis, adjusted for HCT-CI, prior treatment with hypomethylating agents (HMAs), and IPPS-R did not show differences in survival by donor type (HR 0.98, p=0.85; 40% vs. 37%), Figure 1. However, the relapse rate (adjusted for prior HMAs, IPSS-R, and recipient sex) was higher after haploidentical compared to unrelated donor HCT (HR 1.60, p=0.002, 53% vs. 34%), which led to lower disease-free survival after haploidentical HCT (HR 1.30, p=0.03; 21% vs. 32%), Figure 1. To further test the effect of regimen intensity, low dose TBI regimens were compared to Flu/Bu and Flu/Mel; we did not observe a difference in relapse risk (HR 0.95, p=0.76). Non-relapse mortality did not differ by donor type (HR 0.88, p=0.46). Interval between diagnosis and transplant was also not associated with outcomes. Acute grade II-IV acute GVHD (HR 0.46, p&lt;0.001) and chronic GVHD (HR 0.34, p&lt;0.001) was less common after haploidentical HCT. The 1-year graft failure rate was higher after haploidentical compared to unrelated donor HCT (15% and 8%, respectively, p=0.02). Conclusion: Although the current analysis did not show differences in survival between haploidentical related and matched unrelated donor HCT, the higher relapse and consequently lower disease-free survival associated with the haploidentical HCT approach in this analysis (primarily TBI/Cy/Flu with PT-Cy/CNI/MMF) warrants caution. A more definitive comparison of the two donor types can be accomplished only if more haploidentical transplants were to use Flu/Bu or Flu/Mel conditioning. Figure 1 Disclosures Grunwald: Celgene: Consultancy; Pfizer: Consultancy; Agios: Consultancy; Merck: Consultancy; Abbvie: Consultancy; Medtronic: Equity Ownership; Incyte: Consultancy, Research Funding; Daiichi Sankyo: Consultancy; Amgen: Consultancy; Trovagene: Consultancy; Cardinal Health: Consultancy; Janssen: Research Funding; Genentech/Roche: Research Funding; Novartis: Research Funding; Forma Therapeutics: Research Funding. Bolanos-Meade:Incyte Corporation: Other: DSMB fees. Bredeson:Otsuka: Research Funding. Gupta:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sierra Oncology: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Research Funding. Mussetti:Takeda: Honoraria; BMS: Honoraria; Novartis: Honoraria; Italfarmaco: Honoraria. Nakamura:Merck: Membership on an entity's Board of Directors or advisory committees; Celgene: Other: support for an academic seminar in a university in Japan; Alexion: Other: support to a lecture at a Japan Society of Transfusion/Cellular Therapy meeting ; Kirin Kyowa: Other: support for an academic seminar in a university in Japan. Nishihori:Novartis: Research Funding; Karyopharm: Research Funding. Solh:Celgene: Speakers Bureau; Amgen: Speakers Bureau; ADC Therapeutics: Research Funding. Weisdorf:Fate Therapeutics: Consultancy; Pharmacyclics: Consultancy; Incyte: Research Funding.

Fludarabine Melphalan Versus Fludarabine Treosulfan As Reduced Intensity Conditioning Regimens in Allogeneic Hematopoietic Stem Cell Transplant - a Retrospective Analysis

Introduction Allogeneic hematopoietic stem cell transplantation (AHSCT) has evolved as a curative therapy for various hematological malignancies. Regimen-related toxicity and transplant-related mortality (TRM) preclude the use of myeloablative conditioning (MAC) regimens in older and unfit patients. Reduced intensity conditioning (RIC) regimens have enabled AHSCT in such patients. There is a recent rise in use of RIC regimens even in younger patients in view of decreased toxicity and equal efficacy as reported in some studies. Fludarabine + Melphalan (FM) and Fludarabine + Treosulfan (FT) are 2 such regimens. There are no prospective randomised comparisons between these regimens. We retrospectively analysed these 2 regimens for toxicities and outcomes. Methods This is a retrospective single centre analysis of all consecutive patients with haematological cancers who received either FM or FT from April 2008 to December 2018. The entire cohort was divided into two groups - Matched Sibling Donor (MSD)/Matched Unrelated Donor (MUD) and Haploidentical (Haplo) transplants for analysis. We compared patient characteristics, toxicities and outcomes in both the groups based on conditioning regimen. The FT regimen consisted of fludarabine (30 mg/m2 on days − 6 to − 2) combined with treosulfan (12-14 gm/m2 on days − 6 to − 4) with or without 2 Gy TBI on day-1. The FM regimen consisted of fludarabine (30 mg/m2 on days − 7 to − 3) combined with melphalan (140 mg/m2 on day -1).Prophylaxis for GVHD consisted of calcineurin inhibitor (CNI) plus methotrexate (MTX)or mycophenolate mofetil (MMF) in MSD/MUD. Rabbit ATG (2.5-5 mg/kg) was used for MUD. Haplo transplant patients received post-transplant cyclophosphamide with CNI and MMF. Comorbidities were scored according to the HCT-CI. Disease Risk Index(DRI) and EBMT score were recorded for all patients. Neutrophil (NE) and platelet engraftment (PE) were defined as per standard criteria. Early toxicity after AHCT was graded according to CTCAE version 4. Total parenteral nutrition (TPN) was used in patients as per the physician's discretion. Acute GVHD and chronic GVHD were recorded according to standard criteria. All patients underwent chimerism studies at day 15, 30 and then monthly for 1 year. Mixed chimerism was defined as &gt; 5% to &lt; 95% donor chimerism. The toxicities in various arms were compared by Chi-square test or Fisher exact test, while OS was calculated by Kaplan Meier method and the survival probabilities were compared using log-rank test. Competing risk analysis was used to calculate cumulative incidence of relapse and TRM. Results The study included 138 patients, 98 males and 40 females. The diagnoses were AML- 53, ALL- 30, MDS/MPN- 49 and lymphoma -6. Patient characteristics are outlined in Table 1. MSD/MUD transplants were 105 (FM- 94; FT-11); 33 were Haplo (FM-17; FT-16) transplants. PBSC was the stem cell graft in 136 (99%) patients. In both MSD/MUD and Haplo groups, there were no significant differences in median age, gender, pre transplant CMV status, HCT-CI and EBMT score between the two conditioning regimens. In MSD/MUD group, significantly more patients had high/very high DRI in FT arm (45% vs 17%; P=0.056) Comparison of engraftment and toxicity variables of both FM and FT arms are outlined in Table 2. In MSD/MUD group, 44 (47%) patients in FM arm had grade 3/4 oral mucositis compared to 1 (9%) in FT arm (P=0.02). Corresponding numbers were 7 (41%) and 1 (6%) in Haplo group (P=0.039). Grade 3/4 diarrhoea was higher in the FM vs FT arm of Haplo group (41% vs 6%; P=0.039) but not in the MSD/MUD cohort. More patients received TPN in the FM arms of both MSD/MUD and Haplo groups (Table 2). Incidence of grade III-IV acute GVHD was higher in FT vs FM in MSD/MUD group (27% vs 17%; P=0.04). The median follow up of entire cohort was 4.8 years. The OS (figure 1) at 5 years was 62% in FM arm of MSD/MUD group vs 53% in FT arm (P=NS). Similarly OS (figure 2) at 5 years was 41% and 28 %( P=NS) in FM and FT arms respectively of Haplo group. The cumulative incidence of TRM and relapse at 2 years were not different in FM and FT arms of both MSD/MUD and Haplo groups (Table 2). Conclusion Grade 3 and 4 oral mucositis and diarrhoea were significantly less with FT than FM in both MSD/MUD and Haplo groups. FT provided comparable outcomes to FM in the MSD / MUD group in spite of having higher proportions of patients with high / very high DRI. Prospective randomised studies are required to compare various RIC regimens. Disclosures No relevant conflicts of interest to declare.

Graft Versus Host Disease (GVHD) after HLA-Mismatched Haploidentical Transplantation with Post-Transplant Cyclophosphamide Compared to Matched Unrelated Donor: Incidence, Distribution and Response to Therapy

Unmanipulated T-cell replete HLA-mismatched haploidentical transplantation (haplo) with post-transplant cyclophosphamide (PTCY) is now widely used for patients lacking a suitably matched donor. The use of PTCY post haplo results in lower chronic GVHD rates compared to match unrelated donors (MUD) without PTCY. GVHD after PTCY in the haplo setting may have different presentation, response to treatment and impact on survival endpoints compared to a standard GVHD prophylaxis of calcineurin inhibitor plus MMF or methotrexate for MUD patients. To check for differences in GVHD presentation and response to treatment between MUD and haplo with PTCY, we assessed 394 consecutive patients who developed acute or chronic GVHD after receiving their first allogeneic transplantation (HCT) from a 10/10 HLA MUD (n=179) or a haplo (n=215) at our center between 2008 and 2017. Median follow up for survivors was 52.5 months. Our institution has prospectively documented onset, grading and therapy of patients with GVHD using a single dedicated practitioner since 2005. All haplo patients received standard GVHD prophylaxis of tacrolimus (days 5-180), MMF (stop day 35) and PTCY at 50mg/kg on days 3 and 4. Most commonly used GVHD prophylaxis for MUD patients were tacrolimus/methotrexate (68%) and tacrolimus/MMF (26%). MUD recipients were older (median age 56 vs 53 years, p=0.007), were more likely to be white (93% vs 58%, p&lt;0.001), received mainly PBSC as graft source (76% vs 63%, p0.013) and had a higher HCT-comorbidity index (HCT-CI≥3, 64% vs 47%, p&lt;0.001) compared to haplo recipients. The cumulative incidences for grade II-IV and III-IV aGVHD at day 180 post HCT were similar between both donor sources at 35% and 11% for haplo compared to 44% and 16% for MUD (p=NS). Haplo patients had lower cumulative incidence of mod-severe cGVHD at 22% versus 31% for MUD (p=0.026).The median times to onset of grade II-IV acute GVHD and moderate-severe chronic GVHD were: acute, 56 vs 49 days (p=0.19) and chronic 213 vs 280 days (p=0.011) for haplo versus MUD patients respectively. Among patients with grade II-IV acute GVHD, there was no significant difference in organ involvement between Haplo (n=101) and MUD (n=96) with skin being most commonly affected (74% haplo vs 71% MUD), Gut (70% haplo vs 69% MUD) and liver (14% haplo vs 17% MUD). For patients who developed chronic GVHD, organ involvement distribution is shown in table 1. Haplo patients had less involvement of the eyes (46% vs 75% for MUD, p&lt;0.001) and of the joints/fascia (12% vs 36%, p=0.001). Among patients who developed grade II-IV acute GVHD, there was no difference in all-cause mortality (28% vs 19%, p=0.34) and being off immunosuppression at one 1 year (49% vs 51% p=0.80) between haplo and MUD recipients. Among patients who developed cGVHD, haplo recipients had similar all-cause mortality (22% vs 18%, p=0.89) but were more likely to be off immunosuppression at 2 years post HCT (63% vs 43% p=0.03) compared to MUD (figure 1). A cox model was conducted on survival and relapse endpoints where donor type was retained in all models. The fixed covariates tested in Cox models included age (&lt;55, &gt;=55), gender, race, diagnosis, regimen intensity, graft source (BM, PBSC), disease risk index (low/intermediate, high/very high), CIBMTR risk (low, intermediate, high), HCT-CI (0-2, &gt;=3), CMV status, year of transplantation (2008-2012, 2013-2015, 2016-2017). The following variables were evaluated as time-dependent covariates in Cox models: all-grade cGVHD, moderate-severe cGVHD, severe cGVHD, grade 2-4 aGVHD, grade 3-4 aGVHD. Variables were selected if p values were less than 0.05. Developing grade 3-4aGVHD and severe chronic GVHD were both associated with worse OS, DFS and TRM (table 2). Both aGVHD and cGVHD were not significant factors for relapse. Our analysis reveals that compared to MUD, haplo transplant results in significantly lower incidence of moderate-severe chronic GVHD, faster cGVHD onset, different organ distribution and a higher chance of coming off immunosuppression. This data, added to prior publications from our center and others showing similar OS and DFS between MUD and haplo, enforces the notion that haplo transplant with PTCY is at least equivalent to MUD transplant. An ongoing BMTCTN 1702(CTRL-ALT-D) study will help answer assess this in a prospective fashion. figure 1: Chronic GVHD patients who are Immunosuppression free at 2 years Table 1: Organ Distribution of Chronic GVHD by Donor Type Disclosures No relevant conflicts of interest to declare.

Restrictive Transfusions in the Era of Pathogen-Inactivated Platelets: A Single Center Experience

Introduction Blood management and infectious disease mitigation are essential for success with allogeneic stem cell transplant (alloSCT). We sought to investigate the safety profile of a proactive infection mitigation strategy with the use of pathogen-inactivated (PI) platelets (PLT) during the alloSCT peri-engraftment period in the era of restrictive blood transfusion. Methods We retrospectively analyzed data from patients undergoing alloSCT that received prophylactic red blood cell (RBC) and PLT transfusion triggered by a hemoglobin of 8 g/dL and PLT count of 15,000 PLT/mL. When available, PI PLT (non-irradiated) were used starting November 2016 until March 2018 (study timeframe). Statistical analysis was performed using SAS 9.4 (Cary, NC). Patients characteristics and clinical parameters were summarized using mean and standard deviation or median and range for continuous data, and frequency and percentage for categorical data. Kaplan-Meier analysis was used to estimate progression-free survival (PFS) and overall survival (OS) from day of transplant. A two-sided logrank test was used to compare across strata using p Results Sixty-eight patients received alloSCT. Median age at transplant was 55 years (range [R], 18-73). Peripheral blood stem cells were the graft source in all but one patient. Donor source was a matched related, 10/10 matched unrelated (MUD), 9/10 MUD and haploidentical donor in 30.9%, 44.1%, 2.9%, and 22.1% of cases, respectively. Myeloablative conditioning was used in 45.6% of patients. Indication for alloSCT was a myeloid or lymphoid disorder in 64.7% and 35.3% of cases. Median time to neutrophil and PLT engraftment was 12 (R, 10-35) and 12 days (R, 8-120), respectively. Pre-alloSCT RBC alloimmunization was present in 11.8% of patients. Cumulative incidence of grades II-IV acute and chronic graft-versus-host disease (GVHD) was 20.6% and 22.1%, respectively. PI PLT were used in 73.5 % patients. There were no cases of transfusion associated graft failure (GF) or GVHD. Bacteremia occurred in 10.0% and 22.1% of patients by 30 days and 100 days post-alloSCT, respectively, and were both associated with worse OS (both p Conclusions Restrictive prophylactic transfusion thresholds in alloSCT recipients is feasible. Limited PI PLT transfusion was not associated with transfusion-attributable GVHD, GF or infectious complications. Future prospective studies should determine the short term hemostatic efficacy and long term post-alloSCT outcomes with restrictive transfusion criteria in an era of expanding PI product use.

Prevalence of Latent Tuberculosis in Patients Undergoing Hematopoietic Stem Cell Transplantation and Risk of Disease Activation in an Endemic Population

Introduction Latent tuberculosis infection (LTBI) affects one third of the worldOs population. It is well known that patients with immunodeficiency are at a higher risk of developing active tuberculosis (ATBI). Hematopoietic stem cell transplant (HSCT) recipients have and incidence of ATBI 10 to 40 times higher when compared to general population, related to high morbidity and mortality. Objectives Our aim was to determine prevalence of LTBI and incidence of ATBI in recipients and donors of HSCT living in an endemic country. Methods We retrospectively analyzed clinical data of patients that underwent HSCT between January 2010 and December 2016 at our Institution. Results We included 200 patients, 63 allogeneic-HSCT (allo-HSCT) recipients, 74 autologous-HSCT (auto-HSCT) recipients, and 63 HSCT donors. Median age was 36 years (11-68) and 57.5% were male (n=115). Main baseline diagnosis that led to HSCT were: acute leukemia in 27.7%, lymphoma in 23.4%, and monoclonal gammopathy in 20.4% (figure 2). The source of HSCT was peripheral blood (PB) in 83 patients, bone marrow (BM) in 21, and primed-BM in 21 patients. Allo-HSCT donors were matched-related (MRD) in 85.7%, matched unrelated (MUD) in 6.3%, and haploidentical in 9%. All patients were evaluated pre-HSCT with tuberculin skin test (TST) and chest x-ray. Patients with positive TST (n=54) were further evaluated to rule out ATBI with chest-CT (n=54) and smear and culture in either sputum (n=28), gastric fluid (n=16), and urine (n=27), with no positive results. Rates of LTBI were 17% in all-HSCT recipients, 24% in auto-HSCT, and 39% in donors. All patients diagnosed with latent tuberculosis received treatment with isoniazid 300mg for at least 6 months. Interestingly, any patient developed ATBI after transplantation. According to state of residence, most cases were detected in states were lower socioeconomic status and related to migration corridors (Figure 1). Conclusions To our knowledge, this is the first study that evaluates the prevalence of LTBI among HSCT recipients in a Latin American country where TB is endemic. We identified a prevalence of LTBI similar to the estimations of the WHO, however, unlike other published reports from developed and developing countries we have no incidence of active tuberculosis in our population despite Mexico is an endemic country. Figure 1 Cases distribution according patients state of residence.

Hematopoietic stem cell transplantation for adult patients with isolated NPM1 mutated acute myeloid leukemia in first remission.

Acute myeloid leukemia (AML) in first remission (CR1) with isolated NPM1 mutation (iNPM1m) is considered a good prognosis genotype, although up to one-third relapse. To evaluate the best transplant strategy, we retrospectively compared autologous stem cell transplantation (auto-SCT), related (MSD), and fully matched unrelated (MUD) allogeneic stem cell transplantation (allo-SCT). We identified 256 adult patients including 125 auto-SCT, 72 MSD, and 59 MUD. The 2-year leukemia-free survival (LFS) was 62% in auto-SCT, 69% in MUD, and 81% in MSD (P = .02 for MSD vs others). The 2-year overall survival (OS) was not different among auto-SCT, MUD, and MSD, reaching 83% (P = .88). The 2-year non-relapse mortality (NRM) was 2.5% in auto-SCT and 7.5% in allo-SCT (P = .04). The 2-year cumulative incidence of relapse (RI) was higher after auto-SCT (30%) than after MUD (22%) and MSD (12%, P = .01). In multivariate analysis, MSD versus auto-SCT but not MUD versus auto-SCT was associated with lower RI (P < .01 and P = .13, respectively) and better LFS (P = .01 and P = .31, respectively). Age correlated with higher NRM (P < .01). Allo-SCT using MSD appears as a reasonable transplant option for young patients with iNPM1m AML in CR1. Auto-SCT was followed by worse RI and LFS, but similar OS to both allo-SCT modalities.

Influence of Donor Type (sibling vs matched-unrelated donor vs haplo-identical donor vs cord blood) on Outcomes after Clofarabine-Based Reduced-Intensity Conditioning Allograft for Myeloid Malignancies

Background: Recently, we have reported the good results of a clofarabine-based reduced-intensity conditioning (RIC) regimen for peripheral blood stem cell (PBSC) allografts, using either matched (Le Bourgeois, ASH 2017) or haploidentical (haplo) donors (Chevallier, ASH 2017). However, the influence of donor type in this setting is unknown.Patients and Methods: We conducted a retrospective study including all adults (≥18 yo) allografted in our department with a clofarabine-based RIC regimen for a myeloid malignancy. All types of donors were accepted, and patients received allogeneic peripheral blood stem cells (PBSC) or cord blood (CB) transplants. The aim of this study was to assess whether or not the donor type (sibling, matched unrelated (MUD), haplo or CB) impacted outcomes.Results: Between October 2009 and February 2018, 122 patients met the inclusion criteria. Donors were sibling in 36 cases, “MUD” in 55 (including one 9/10 mismatched donor), haplo in 27 and CB in 4. The sibling+MUD patients received a CloB2A1/A2 RIC regimen consisting of clofarabine 30 mg/m²/day 4 to 5 days (Clo), busulfan 3.2 mg/kg/day 2 days (B2) and 2.5mg/kg/day of rabbit anti-thymocyte globulin 1 or 2 days (A1 or A2). Haplo and CB recipients were conditioned by a Baltimore-like RIC regimen and a Minneapolis-like regimen, respectively, where fludarabine were replaced by clofarabine. All patients received cyclosporine (CsA) + mycophenolate mofetyl as GVHD prophylaxis, except sibling recipients who were given CsA alone. Haplo recipients received also 2 days of post-transplant cyclophosphamide. All non-CB patients received PBSC as source of graft.The median age of the whole cohort was 61,5 years old (range: 18-73) and the median follow-up 31 months (range: 4,5-106). All patients engrafted except 1 CB patient and 1 haplo recipient who died of infection before engraftment. All CB cases died at 1, 8, 9 and 11,5 months post-transplant, respectively (infection n=1, relapse n=2, chronic GVHD n=1). As a consequence, we thereafter compared outcomes only between the three other donor groups.There were no significant differences between sibling, MUD or haplo recipient groups in terms of gender, median age, type of disease, ELN 2010 classification for AML, status at transplant (complete remission vs active), disease risk index, donor/recipient CMV status or median graft quantity of CD34+ stem cells. The only differences were the partition of ABO compatibility, less frequent in the MUD group (42% vs sibling 69% vs haplo 67%, p=0,02) and a history of previous allograft (haplo n=7, sibling n=0, MUD n=6, p=0,005).Neutrophils (>0,5 Giga/L) and platelets (50 Giga/L) recoveries were significantly delayed in the haplo-group (19 days, vs sibling 15 vs MUD 15, p=0.0003; and 31 days vs 11 vs 12, p<0.0001).Acute grade 2-4 or 3-4 graft versus host disease (GVHD) incidences were similar between the three groups at 50% and 22% for sibling, 34,5% and 14,5% for MUD and 48% and 11% for haplo (p=0,18 for grade 2-4 and p=0,45 for grade 3-4) as well as moderate+severe chronic GVHD incidences (sibling 14%, MUD 16%, haplo 15% p=0,94).Follow-ups were similar at 34.2 (6-74), 33.7 (4.5-106) and 21.4 (7-53) months respectively for sibling, MUD or haplo donors. This was associated with similar 2-year overall survivals (OS) at 64,7% (50-83), 73,9% (62-87) and 60,2% (43-83) respectively (p=0.4) and 2-year disease-free survivals (DFS) at 57,7% (43-76), 70,9% (59-84) and 53,6% (37-77) respectively (p=0.1). Two-year GVHD-relapse free survival (GRFS) was also similar at respectively 37,9% (24-57), 54,3% (41-70) and 38,9% (23-63) (p=0.2) as well as 2-year non-relapse mortality (NRM) at 14%, 11% and 18,5% (p=0,63).When considering only AML patients, again similar 2-year survivals were observed between the three groups. OS was 71.4% (54-93) for sibling (n=21), 75.1% (62-90) for MUD (n=40) and 66.6% (46-95) for haplo (n=15, p=0.65) and DFS respectively 66,6% (49-90), 70,8% (57-87) and 66,6% (46-95 p=0.47). The same was observed for GRFS at 38% (22-65), 56% (41-75) and 40% (21-74, p=0.14) and NRM at 14%, 7,5% and 7%, p=0.34).In multivariate analysis, donor type remained independent of outcomes in this series.Conclusion: These data confirm that since no difference was observed in terms of outcomes, haplodonors represent a valid alternative for patients receiving a clofarabine-based RIC PBSC allograft for myeloid malignancies who lack a matched sibling donor. DisclosuresGastinne:Millennium/Takeda: Honoraria. Moreau:Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Analysis of Risk Factors Determining Incidence and Outcome of Infections in Children and Adults after Hematopoietic Cell Transplantation

BACKGROUNDRecent EBMT analysis showed that infections are responsible for 21% of deaths after allo-HCT and 11% after auto-HCT. However, the risk, types and outcome of infections vary between age groups. The aim of the study is the direct comparison of risk factors of incidence and outcome of infections in children and adults. PATIENTS AND METHODSWe analyzed risk factors for the incidence and outcome of bacterial, fungal, and viral infections in 650 children and 3200 adults who received HCT between 2012-2015. The risk factors were determined by multivariable logistic regression analysis. RESULTSA total number of 395/650 (60.8%) children and 1122/3200 (35.0%) adults were diagnosed for microbiologically confirmed infection, including 345/499 (69.1%) and 679/1070 (63.5%), respectively after allo-HCT, and 50/151 (33.1%) and 443/2130 (20.8%) respectively, after auto-HCT. At 2 years after HCT, the incidences of microbiologically documented bacterial infection were 36.0% and 27.6%, (p<0.001) for children and adults, respectively. Incidences of proven/probable invasive fungal disease (IFD) were 8.4% and 3.7% (p<0.001), respectively; and incidences of viral infection were 38.3%, and 13.5% (p<0.001), respectively. Overall, 31/650 (4.8%) children and 206/3200 adults (6.4%) have died after these infections. The distribution of deaths was different in children (35.5% bacterial, 48.4% fungal, 16.1% viral) and adults (61.7% bacterial, 24.7% fungal, 13.6% viral). BACTERIAL INFECTIONS: In multivariable analysis, the risk of infections was higher after allo-HCT (HR=1.8; p<0.001). In allo-HCT patients, the risk was higher in children (HR=2.1; p<0.001), in patients with acute leukemia (HR=1.6; p<0.001), matched unrelated (MUD) vs matched family-donor (MFD) HCT (HR=1.6; p<0.001), mismatched unrelated (MMUD) vs MFD HCT (HR=2.0; p<0.001), myeloablative vs reduced-intensity conditioning (RIC) (HR=1.3; p<0.001), delayed (>21d) hematological recovery (HR=3.3; p<0.001), acute GVHD before infection (HR=1.7; p<0.001), and chronic GVHD before infection (HR=1.4; p=0.014). In auto-HCT patients, the risk was higher in children (HR=1.7; p<0.001), and in patients with delayed hematological recovery (HR=2.8; p<0.001). In patients with multiple myeloma (MM) the risk was decreased (HR=0.7; p=0.005). FUNGAL INFECTIONS: The risk of proven/probable IFD was higher after allo-HCT (HR=5.4; p<0.001). In allo-HCT patients, the risk was higher in children (HR=3.9; p<0.001), in patients with acute leukemia (HR=3.8; p<0.001), MUD vs MFD HCT (HR=1.5; p=0.013), MMUD vs MFD HCT (HR=2.5; p<0.001), delayed hematological recovery (HR=3.3; p<0.001), acute GVHD before infection (HR=1.5; p=0.021), and chronic GVHD before infection (HR=2.2; p<0.001). In auto-HCT patients, the risk was higher in children (HR=1.8; p=0.025). Patients with MM were at decreased risk of IFD (HR=0.6; p=0.005). VIRAL INFECTIONS: In multivariable analysis, the risk of infections was higher after allo-HCT (HR=6.1; p<0.001). In allo-HCT patients, the risk was higher in children (HR=1.3; p=0.010), in patients with acute leukemia (HR=1.7; p<0.001), MUD vs MFD HCT (HR=2.0; p<0.001), MMUD vs MFD HCT (HR=3.3; p<0.001), myeloablative vs RIC (HR=1.8; p=0.050), acute GVHD before infection (HR=1.5; p<0.001) and chronic GVHD before infection (HR=2.7; p=0.014). Among auto-HCT patients, diagnosis of MM brought decreased risk of viral infections (HR=0.5; p<0.001). DEATH FROM INFECTION: In allo-HCT patients, adults (HR=3.3; p<0.001), recipients of MMUD-HCT (HR=3.8; p<0.001), patients with acute leukemia (HR=1.5; p=0.023), chronic GVHD before infection (HR=3.6; p=0.014), CMV reactivation (HR=1.4; p=0.038) and with duration of infection treatment >21 days (HR=1.4; p=0.038) were associated with increased risk of death from infection. Among patients with bacterial infections, the risk was higher in G- infections (HR=1.6; p=0.031). Among auto-HCT patients, no child died of infection. In adults, the risk of death was higher if duration of treatment of infection was >21 days (HR=1.7; p<0.001). In patients with MM the risk was decreased (HR=0.4; p<0.001). CONCLUSIONSThe profile of infections and related deaths varies between children and adults. MMUD transplants, diagnosis of acute leukemia, chronic GVHD, CMV reactivation and prolonged infection are relative risk factors for death from infection after HCT. DisclosuresKalwak:Sanofi: Other: travel grants; medac: Other: travel grants.