Incidence Of Acute GVHD Research Articles

Unmanipulated haploidentical transplantation conditioning with busulfan, cyclophosphamide and anti-thymoglobulin for adult severe aplastic anaemia.

We conducted a retrospective analysis to evaluate outcomes of haploidentical transplantation in adult severe aplastic anaemia (SAA) patients. Fifty-one adults received haploidentical transplantation between May 2011 and December 2016. Patients were administered busulfan (Bu), cyclophosphamide (Cy) and anti-thymoglobulin (ATG) as conditioning regimens, followed by bone marrow and peripheral blood transplantation. The patients' median age was 25 years. Forty-nine patients survived for more than 28 days and all achieved donor myeloid engraftment. The median time for myeloid engraftment and platelet recovery was 13 days (range, 10-21) and 17.5 (range, 7-101) days. The cumulative incidence (CI) of grade II-IV and III-IV acute GvHD) was 20.00±0.33% and 6.00±0.12%, respectively. The incidence of chronic GvHD was 14.00±0.36% and 25.90±0.71%, and that of moderate-severe chronic GvHD was 2.51±0.06% and 6.92±0.25% at 1 and 3 years, respectively. The 3-year estimated overall survival and failure-free survival were both 83.5±5.4% with a median follow-up of 21.1 months. Multivariate analysis showed hematopoietic cell transplantation-specific comorbidity index (HCT-CI) score of ⩾3 was significantly associated with worse outcome. Haploidentical transplantation conditioning including Bu/Cy/ATG was a safe and effective strategy for adult SAA patients, and HCT-CI might be an outcome predictor in these patients.

Similar outcome of allogeneic stem cell transplantation after myeloablative and sequential conditioning regimen in patients with refractory or relapsed acute myeloid leukemia: A study from the Société Francophone de Greffe de Moelle et de Thérapie Cellulaire

Patients with acute myeloid leukemia (AML) in relapse or refractory to induction therapy have a dismal prognosis. Allogeneic hematopoietic stem cell transplantation is the only curative option. In these patients, we aimed to compare the results of a myeloablative transplant versus a sequential approach consisting in a cytoreductive chemotherapy followed by a reduced intensity conditioning regimen and prophylactic donor lymphocytes infusions. We retrospectively analyzed 99 patients aged 18-50 years, transplanted for a refractory (52%) or a relapsed AML not in remission (48%). Fifty-eight patients received a sequential approach and 41 patients a myeloablative conditioning regimen. Only 6 patients received prophylactic donor lymphocytes infusions. With a median follow-up of 48 months, 2-year overall survival was 39%, 95% confidence interval (CI) (24-53) in the myeloablative group versus 33%, 95% CI (21-45) in the sequential groups (P = .39), and 2-year cumulative incidence of relapse (CIR) was 57% versus 50% respectively (P = .99). Nonrelapse mortality was not higher in the myeloablative group (17% versus 15%, P = .44). In multivariate analysis, overall survival, CIR and nonrelapse mortality remained similar between the two groups. However, in multivariate analysis, sequential conditioning led to fewer acute grade II-IV graft versus host disease (GVHD) (HR for sequential approach = 0.37; 95% CI: 0.21-0.65; P < .001) without a significant impact on chronic GVHD (all grades and extensive). In young patients with refractory or relapsed AML, myeloablative transplant and sequential approach offer similar outcomes except for a lower incidence of acute GvHD after a sequential transplant.

Phase 2 Trials with Mgta-456, Single Cord Blood Units (CBU) Expanded with an Aryl Hydrocarbon Receptor (AHR) Antagonist, Demonstrate Uniform Engraftment and Rapid Hematopoietic Recovery in Patients Following Myeloablative or Non-Myeloablative Conditioning

Background. The use of umbilical cord blood (UCB) in transplant has been limited by the low number of CD34+ cells, resulting in prolonged periods of cytopenia for patients and high risk of graft failure, thereby restricting its widespread application. MGTA-456 is the hematopoietic cell product after cord blood CD34+ cells are placed in expansion culture for 15 days with an aryl hydrocarbon receptor (AHR) antagonist in the presence of SCF, Flt-3L, IL-6 and TPO. In a prior Phase 1/2 safety study, 18 patients received MGTA-456, its accompanying CD34negfraction and a larger, unexpanded UCB unit. All patients engrafted at a median of 14.5 days (range, 7-23), significantly faster than similarly treated historical controls (p<0.01). Based on these results, two Phase 2 studies were initiated to evaluate the effectiveness of MGTA-456 as a stand-alone graft after myeloablative conditioning (MAC) or non-myeloablative conditioning (NMAC).Patients and Methods : Twenty patients with high-risk hematologic malignancy and a partially HLA-matched CBU were enrolled; 10 were treated with cyclophosphamide (CY) 120 mg/kg, fludarabine (FLU) 75 mg/m2 and total body irradiation (TBI) 1320 cGy (MAC) and 10 with CY 50 mg/kg, FLU 200 mg/m2 and TBI 200 cGy (NMAC). All patients received cyclosporine and mycophenolate mofetil post-transplant immunoprophylaxis. Expansion was low in 2 UCB units, therefore 18 patients received MGTA-456 and its CD34neg fraction.Results : Expansion culture yielded a median of 1,227 x 106 CD34+ cells (range, 201-8969) as compared to the input number of 4.2 x 106 (range, 1.4-16.3) after CD34 selection - a 324-fold (range, 42-1643) expansion of CD34+ cells. As transplant results vary by intensity of the conditioning, patient outcomes were compared to similarly treated historical cohorts between 2006 and 2015 (n=151 MAC; n=132 NMAC). For both groups, demographics were similar except for more recent year of transplant for recipients of MGTA-456. For recipients of MAC, MGTA-456 engrafted in all patients at a median of 14 days (range, 7-32) as compared to 89% engraftment at a median of 23 days (range, 19-31) in the control population (p<0.01, see Figure 1). Complete chimerism was rapid for both myeloid and T cells with no late graft failures; the longest follow-up was 5.6 years in recipients of MGTA-456. For recipients of NMAC, MGTA-456 also engrafted in all patients at a median of 7 days (range, 6-14) as compared to 94% engraftment at a median of 15 days (range, 7-22). In contrast to complete chimerism seen after MAC, chimerism is often mixed for the first month in both myeloid and T cells after NMAC. Compared to the historical cohort, recipients of MGTA-456 had more rapid chimerism after NMAC. CD34 cell dose correlates with speed of recovery but only in recipients with MAC; in recipients of NMAC, recovery is uniformly rapid regardless of CD34 cell dose. Additionally, immune recovery as measured by an absolute CD4 count >200/uL was achieved at day 60 (median) in recipients of MGTA-456 regardless of conditioning regimen. Results were also encouraging for other transplant outcomes. For recipients of MGTA-456 compared to the historical cohort after MAC, incidence of acute GVHD (aGVHD) grade 3-4 was 22% vs 24%; chronic GVHD (cGVHD), 11% vs 21%; transplant-related mortality (TRM), 11% vs 34%; and overall survival (OS), 67% vs 55%. After NMAC, results were similar between cohorts except for a higher risk of aGVHD in recipients of MGTA-456 (aGVHD 3-4, 43% vs 15%; cGVHD, 0% vs 19%; TRM, 22% vs 20%; and OS, 44% vs 49%). The increased rate of aGVHD in the NMAC cohort likely reflects non-compliance with prescribed GVHD immunoprophylaxis in 2 of 9 recipients.Conclusion : In these studies, MGTA-456 significantly accelerated hematopoietic recovery and abrogated the engraftment barrier typically associated with UCB transplantation. The marked expansion of CD34+ cells in MGTA-456 suggests that a significant number of patients will have an adequate single CBU and better HLA matched graft since a greater proportion of the cord blood inventory will be available irrespective of weight. Given these promising results, additional studies are being planned. [Display omitted] DisclosuresWagner:Novartis: Research Funding; Magenta Therapeutics: Research Funding. Brunstein:Novartis: Research Funding; Magenta Therapeutics: Research Funding. Boitano:Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties; Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. McKenna:Magenta Therapeutics: Research Funding; Novartis: Research Funding. Sanna:Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. Bleul:Hoffmann-La Roche AG: Employment. Cooke:Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties.

Impact of HLA Disparity in Haploidentical Bone Marrow Transplantation Followed by High-Dose Cyclophosphamide

We studied the impact of HLA mismatching on the outcome of 318 consecutive patients who received an unmanipulated haploidentical bone marrow transplant, followed by post-transplant cyclophosphamide (PTCy). The number of HLA-mismatched antigens was tested for its impact on overall survival (OS) and nonrelapse mortality (NRM), whereas HLA mismatches in the graft-versus-host (GVH) direction were tested for prediction of graft-versus-host disease (GVHD and relapse. Finally, we studied whether graft rejection correlated with the number of HLA mismatched antigens in host-versus-graft (HVG) direction. Two hundred thirty-one donor–recipient pairs (72%) had 4/8 mismatches at the -A, -B, -C, -DRB1 HLA loci. HLA mismatches did not predict the 2-year OS (hazard ratio, .83; P = .58) and NRM (subhazard ratio, 1.08; P = .93). The cumulative incidence of acute GVHD (P = .13), 1-year chronic GVHD (P = .84), and relapse rate (P = .26) did not correlate with univectorial GVH mismatches. Similarly, no correlation was observed between the amount of HLA mismatch in the HVG direction and graft rejection. In multivariate analysis advanced disease at transplant was the strongest predictor of survival, NRM, relapse, and graft rejection. In conclusion, the degree of HLA mismatching should not be used as a criterion to select family haploidentical donors when using bone marrow as stem cell source and PTCy for GVHD prophylaxis.

Allogeneic stem cell transplantation and subsequent treatments as a comprehensive strategy for long-term survival of multiple myeloma patients.

We evaluated 71 patients treated with allogeneic hematopoietic cell transplantation (allo-HCT) for multiple myeloma (MM). Forty-three patients (61%) received allo-HCT after the first line of therapy. Fifty-eight patients (82%) had chemosensitive disease at the time of allo-HCT. A HLA-matched related or unrelated donor was available for 68 patients (96%). Non-myeloablative or reduced-intensity conditioning regimen and peripheral blood hematopoietic cells as a graft source were used in most patients. The cumulative incidence of grade II-IV acute GVHD at day +100 and chronic GVHD at 5 years was 13% (95% CI 7-23%) and 35% (95% CI 24-46), respectively. Non-relapse mortality and relapse/progression incidence at 5 years were 12% (95% CI 5-23) and 65% (95% CI 49-76), respectively. With a median follow-up in survivors of 100 months (range 16-186), the 5-year PFS and OS were 39% (95% CI 27-52) and 60% (95% CI 55-77), respectively. On multivariate analysis: age >55 years was associated with both a reduced PFS (RR 2.11, 95% CI 1.15-3.87) and OS (RR 5.53, 95% CI 2.22-13.76); chemorefractory disease at allo-HCT was associated with both reduced PFS (RR 3.09, 95% CI 1.37-7.00) and OS (RR 3.19, 95% CI 1.23-8.22). At relapse, 24 patients (56%) received bortezomib, 28 (65%) lenalidomide, 11 (26%) pomalidomide, 16 (37%) donor lymphocytes infusion as part of salvage therapy after allo-HCT relapse. Median PFS from time of salvage treatment was 7 months (range 0-113 months) for bortezomib-based therapy, 14 months (range 0-79 months) for lenalidomide and 10 months (range 1-28) for pomalidomide. Allo-HCT is a feasible and effective strategy in selected patients with MM and could be an effective platform for subsequent therapies.

Comparison of unrelated cord blood transplantation and HLA-identical sibling peripheral blood stem cell transplantation for the treatment of adult hematological malignancies

目的比较单份清髓非血缘脐血移植（UCBT）与HLA相合同胞外周血干细胞移植（PBSCT）治疗成人恶性血液病的疗效。方法自2011年4月1日至2015年12月31日，共81例单份清髓UCBT与57例HLA相合同胞PBSCT患者入组进行比较。所有患者均采用清髓性预处理方案，环孢素A联合霉酚酸酯预防移植物抗宿主病（GVHD）。结果移植后42 d（+42 d）UCBT组中性粒细胞累积植入率为95.0%（95%CI 87.0%~98.1%），同胞PBSCT组为100%（P=0.863）。+100 d UCBT组血小板累积植入率低于同胞PBSCT组[87.3%（95%CI 76.8%~93.1%）对98.2%（95%CI 87.3%~99.7%），P=0.005]。+100 d UCBT组Ⅱ~Ⅳ度急性GVHD、Ⅲ/Ⅳ度急性GVHD的累积发生率分别为18.2%（95%CI 9.1%~26.4%）、10.4%（95%CI 3.3%~16.9%），同胞PBSCT组分别为8.9%（95%CI 1.1%~16.1%）、7.1%（95%CI 1.4%~13.7%），差异均无统计学意义（P=0.142，P=0.521）。UCBT组3年慢性GVHD、广泛型慢性GVHD累积发生率均低于同胞PBSCT组[14.9%（95%CI 5.2%~23.5%）对35.2%（95%CI 19.4%~47.8%），P=0.008；11.2%（95%CI 2.9%~18.7%）对31.4%（95%CI 16.2%~43.9%），P=0.009]。UCBT组、同胞PBSCT组3年移植相关死亡率（TRM）差异无统计学意义[30.1%（95%CI 19.2%~41.7%）对23.2%（95%CI 13.1%~35.0%），P=0.464]。UCBT组3年疾病复发率低于同胞PBSCT组[12.9%（95%CI 6.6%~21.5%）对24.3%（95%CI 13.5%~36.8%），P=0.039]。UCBT、同胞PBSCT组3年总生存率、无病生存率差异均无统计学意义[58.6%（95%CI 45.4%~69.7%）对54.8%（95%CI 39.9%~67.4%），P=0.634；57.0%（95%CI 44.0%~68.0%）对52.4%（95%CI 38.2%~64.9%），P=0.563]。UCBT组3年无GVHD及复发生存（GRFS）率高于同胞PBSCT组[55.7%（95%CI 44.1%~65.8%）对42.9%（95%CI 29.8%~55.3%），P=0.047]。结论对于成人恶性血液病，UCBT与HLA相合同胞PBSCT具有相似的急性GVHD发生率、TRM、总生存率和无病生存率，但UCBT组具有较低的慢性GVHD发生率及疾病复发率。

Elevated bone marrow eosinophil count is associated with high incidence of severe acute GvHD after allogeneic hematopoietic stem cell transplantation.

Predicting severe acute GvHD (aGvHD) after allogeneic hematopoietic stem cell transplantation (HSCT) is challenging but critical. Mild aGvHD may have a favorable impact on relapse, whereas severe aGvHD is associated with poor outcomes. The aim of this study was to evaluate whether elevated eosinophil count in the bone marrow (BM) at 1 month after HSCT is associated with a high incidence of new and severe aGvHD. We enrolled 101 consecutive patients; median age was 50 years, and 50.5% patients were male. The median eosinophil concentration in BM at 1 month after HSCT was 1.1% (quartile 0.4-2.2%). The adjusted hazards ratio at 95% confidence interval for severe aGvHD was 1.26 (1.12-1.42, P<0.001), per 1% increase in eosinophil concentration, and 3.76 (1.41-10.05, P=0.008) for the high-risk group at a cutoff value of 4.0%. In addition, the predictive accuracy described by area under the curve of receiver operating characteristics, increased from 0.784 to 0.866 (P=0.033) with the increasing concentration of eosinophils. In conclusion, elevated concentration of eosinophils in BM was associated with high incidence and predictive accuracy of severe aGvHD. BM eosinophil concentration can be one of the key markers to predict aGvHD.

Cost effectiveness of G-CSF after allogeneic peripheral blood stem cell transplant.

e18540 Background: In spite of the fact G-CSF has been used post stem cell transplant (SCT) to accelerate neutrophil engraftment its use post allogeneic SCT remains controversial. ASCO does not recommend its use after allogeneic SCT. To further evaluate the effectiveness of its use, we compared outcomes in pts who underwent related and unrelated peripheral blood SCT(PBSCT) either with or without the use of G-CSF post SCT. Methods: This is a retrospective study comparing early outcomes in pts who received G-CSF starting on day + 6 post SCT until engraftment with pts who did not receive a planned course of G-CSF. Pts who underwent Allogeneic PBSCT between 2012-2014 at our institution were included. Pts who received marrow, haploidentical or cord blood transplants were excluded. Associations with survival outcomes were assessed by univariable and multivariable Cox proportional regression models. Results: A total of 162 patients were evaluated. Sixty-five pts received G-CSF post SCT and 97 did not. The only difference between the two groups was that more pts in the G-CSF group received myeloablative-conditioning (MAC) regimen (78% vs. 55%, p = 0.008). Other pt characteristics were not significantly different. Length of hospital stay was significantly lower in the G-CSF group (24 vs. 27 days P = 0.002). Pts who received G-CSF had earlier neutrophil engraftment (median, days 11 vs. 14 p = &lt; 0.001). The median day of platelet engraftment was 15 days in both groups. There was no significant difference between the 2 groups in re-admissions in the first 100 days, and the incidence of acute or chronic GVHD. In multivariate analysis use of G-CSF did not significantly impact non- relapse mortality, relapse free survival and overall survival. However, relapse rate was significantly lower in G-CSF group in multivariable analysis (hazards ratio = 0.44, p = 0.03). Conclusions: Use of G-CSF post allogeneic PBSCT is associated with earlier neutrophil engraftment, shorter hospital stay and a suggestion of a reduced relapse rate after PBSCT. Our experience suggests that use of G-CSF (on average for approximately 5 days) in this setting is cost effective as it reduces hospitalization duration without adversely impacting post-transplant outcomes.

307 - Acute GvHD Incidence and Outcome: Single Center Experience

307 - Acute GvHD Incidence and Outcome: Single Center Experience

317 - Augmenting GVHD Prophylaxis in Allogeneic Hematopoietic Stem Cell Transplant for Beta Thalassemia Major Reduces Acute GVHD Incidence and Severity without Impacting Engraftment

317 - Augmenting GVHD Prophylaxis in Allogeneic Hematopoietic Stem Cell Transplant for Beta Thalassemia Major Reduces Acute GVHD Incidence and Severity without Impacting Engraftment

Allogeneic stem cell transplantation for refractory acute myeloid leukemia in pediatric patients: the UK experience.

We report outcomes for 44 children who underwent stem cell transplantation (SCT) for refractory AML in the UK between 2000 and 2012. Median age at SCT was 11.5 years. Twenty-three patients had primary refractory and 21 relapsed refractory AML. Refractory disease was confirmed by cytogenetics/molecular genetics in 24 cases. Median follow-up of the whole cohort is 6.8 years (2.1-14.9 years). Thirty patients (68%) achieved a CR following SCT. Transplant-related mortality at 1 year was 18%. Acute GVHD incidence was 52% (grade ⩾III 19%), chronic 7%. Relapse was the major cause of treatment failure and occurred in 32% of patients at a median of 61 days post SCT. Five-year overall survival and leukemia-free survival (LFS) were 43% (95% CI 31-61%). All patients with favorable cytogenetics (n=6) are alive in CR. Outcomes in patients with primary refractory disease were equivalent to those with relapsed refractory AML. Blast percentage ⩽30% in the BM pre-SCT, myeloablative conditioning and acute GVHD proved to be favorable prognostic features. We could stratify patients according to age ⩾10 years and >30% blasts in BM pre-SCT. Patients with none/one of these risk factors were highly salvageable (5 years LFS 53%) whereas those with both factors had a very poor prognosis (5 years LFS 10%). This may facilitate decision making on whether it is appropriate to consider transplant in such patients.

Clinical and immunologic impact of CCR5 blockade in graft-versus-host disease prophylaxis

AbstractGraft-versus-host disease (GVHD) is a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Lymphocyte trafficking via chemokine receptors such as CCR5 plays a critical role in alloreactive responses, and previous data suggest that CCR5 blockade with maraviroc results in a low incidence of visceral GVHD. However, the full scope of clinical and immunologic effects of CCR5 blockade in HSCT has not been described. We compared a cohort of patients enrolled on a trial of reduced-intensity allo-HSCT with standard GVHD prophylaxis plus maraviroc to a contemporary control cohort receiving standard GVHD prophylaxis alone. Maraviroc treatment was associated with a lower incidence of acute GVHD without increased risk of disease relapse, as well as reduced levels of gut-specific markers. At day 30, maraviroc treatment increased CCR5 expression on T cells and dampened T-cell activation in peripheral blood without impairing early immune reconstitution or increasing risk for infections. Patients who developed acute GVHD despite maraviroc prophylaxis showed increased T-cell activation, naive T-cell skewing, and elevated serum CXCL9 and CXCL10 levels. Collectively, these data suggest that maraviroc effectively protects against GVHD by modulating alloreactive donor T-cell responses, and that CXCR3 signaling may be an important resistance mechanism to CCR5 blockade in GVHD.

Is day +1 omission of methotrexate associated with higher incidence of acute GvHD in hematopoietic stem cell transplantation?

Is day +1 omission of methotrexate associated with higher incidence of acute GvHD in hematopoietic stem cell transplantation?

Factors Influencing the Outcome of Hematopoietic Stem Cell Transplantation in Pediatric Acute Myeloid Leukemia: Single Institution Results from Saudi Arabia

Medical records of 73 patients with AML who underwent HCT, 2005-2011. The OS was 51.8% and the EFS were 48%. Median follow-up time for the cohort was 50.667 ± 2.4 months (95%CI: 45.9-55.4). 39 patients were alive with a median follow-up time of 50.1 months (Min: 1.8, Max: 111.8). Sixteen patients survived for more than 5 years (Min: 65.2, Max: 111.8 months). The cumulative incidence of acute GVHD was 6.8 ± 2.9 and of chronic GVHD was 9.9 ± 3.6. Median time to ANC and platelet recovery was 16 days (range 9-37) and 29 days (range 15-180) respectively. Three patients acquired CMV infection after transplant. There was a significant impact of patient’s age at diagnosis on the overall survival (Infantile: 100%, others: 45.6% ± 6.4%, P=0.016) and event free survival (Infantile: 100%, others: 40.6% ± 7.1%, P=0.013). Percentage of blasts at transplant, patients or donors gender, donor source and HLA disparity did not significantly affect OS or EFS.

Lower Incidence of Acute Gvhd Is Associated with the Rapid Recovery of CD4+CD25+CD45RA+ Regulatory T Cells in Patients Who Received Haploidentical Allografts from NIMA-Mismatched Donors: A Retrospective (development) and Prospective (validation) Cohort-Based Study

To investigate the effects of non-inherited maternal antigen (NIMA) on clinical outcomes and immune recovery, especially of regulatory T cells (Tregs), in patients who underwent unmanipulated haploidentical transplantation.A retrospective cohort (n=57) and a prospective cohort (n=88) were included. Reconstitution of immune subsets, including Tregs, was determined using multicolor flow cytometry. In the retrospective cohort, the cumulative incidence of grades II-IV acute GVHD in patients with NIMA-mismatched donors was significantly lower than that of cases with NIPA-mismatched donors (14.8% vs. 43.30%, P=0.018). Patients with higher percentages of CD4+CD25+CD45RA+ T cells (naive Tregs) within CD4+ T cells recovered on day 30 (≥1.55%) experienced a significantly lower incidence of grades II-IV acute GVHD than that of cases with lower percentages of naive Tregs (<1.55%) (13.8% vs. 46.4%, P=0.010). Multivariate analysis showed that NIMA mismatch and the percentages of naive Tregs were associated with the incidence of grades II-IV acute GVHD [P=0.050, and 0.031, respectively]. In the prospective cohort, the association of NIMA mismatch [HR=0.365, 95%CI, 0.169-0.786, P=0.010] or higher percentages of naive Tregs recovered on day 30 (≥1.55%) [HR=0.114, 95%CI, 0.027-0.479, P=0.003] with a lower cumulative incidence of grades II-IV acute GVHD was further demonstrated. No effects of NIMA mismatch on chronic GVHD, transplant-related mortality, relapse, disease-free survival, or overall survival were found. Our results confirmed the role of NIMA mismatch in acute GVHD and provided the first demonstration, based on clinical data, that recovered Tregs may be involved in the effects of NIMA on acute GVHD in a haploidentical transplant setting. DisclosuresNo relevant conflicts of interest to declare.

Low Dose Antithymocyte Globulin (ATG) for Graft-Versus-Host Disease (GVHD) Prophylaxis

ATG appears to reduce the incidence of acute and chronic GVHD after allogeneic hematopoietic stem cell transplantation (HSCT). Potential risks of this strategy include viral reactivation, delayed immune recovery and increased relapse rates. The ideal dosing of rabbit ATG in this context is largely unknown. We therefore hypothesized that low dose ATG would reduce the incidence of acute and chronic GVHD in matched unrelated donor (MUD) transplants without compromising survival and relapse rate. A retrospective analysis was performed of a cohort of high-risk MUD HSCT recipients treated since year 2013, when our practice changed to include rabbit ATG at 3 mg/Kg for all MUD transplants at the Case Medical Center in Cleveland, Ohio. Herein we present the results of this analysis.Methods. 58 MUD transplants were performed between years 2013 and 2016, with a median follow up of 262 days post-transplant. All donor-recipient pairs were matched by high resolution HLA typing at HLA-A, -B, -C, and DRB1, (8/8 matches) with the exception of 4 pairs (7/8 matches. Median age was 56 years (range, 53-64). Underlying diagnoses were AML (n=26), MDS (13), CML (n=5), NHL (n=9), Hodgkin's lymphoma (n=2), Multiple Myeloma (n=1) and myeloproliferative disorders (n=2). Preparative regimens were ablative in 26 cases (45 %) and of reduced intensity in 31 cases (55 %). Graft source was bone marrow (n=5) and peripheral blood (n=53). All but 4 pts received GVHD prophylaxis with tacrolimus, and mini-methotrexate (5 mg/m2 on days +1, +3, +6 and +11), in addition to rabbit ATG 3 mg/Kg divided in two doses on days -2 and -1 pre HSCT. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Human Herpes Virus (HHV6) PCR were conducted thrice weekly during the first 100 days after HSCT.Results. The 100-day cumulative incidence of grade II-IV acute GVHD was 41% (95% CI: 29-57; Fig 1), while the cumulative incidence of grade III-IV acute GVHD was 18% (95% CI: 9-35; Fig 2). 1-year cumulative incidence of chronic GVHD was 27% (95% CI: 17-42; Fig 3). At 180 days, the incidence of CMV viremia (defined as more than 1,000 copies/mL) was 25% (95% CI: 16-40), while the incidence of EBV and of HHV6 viremia was 35% (95% CI: 24-51) and 14% (95% CI: 8-27), respectively. There was no instance of EBV-related lymphoproliferative disorder.3-year overall survival estimate is 48% (95% CI: 34-62). Cumulative incidence of Non-relapse mortality (NRM) and relapse at 1 year was 21% (95% CI: 12-37) and 44% (95% CI: 29-65), respectively.Conclusion. Our study shows that low dose rabbit ATG appears to reduce chronic GVHD rates without a major effect on acute GVHD incidence. CMV, EBV and HHV6 reactivation did occur, albeit at rates that are somewhat lower than those historically reported, without EBV-driven lymphoproliferative disorder. [Display omitted] [Display omitted] [Display omitted] DisclosuresCaimi:Genentech: Speakers Bureau; Roche: Research Funding; Novartis: Consultancy; Gilead: Consultancy.

Optimal Outcomes after Second Hematopoietic Stem Cell Transplantation in Patients with Thalassemia Recurrence Following Graft Failure/Rejection of the First Graft

Introduction. Graft failure/rejection (GF/R) is a significant complication following HCT in non- malignant diseases. The risk of GF/R in patients with thalassemia is particularly high as a consequence of alloimmunization related to transfusion exposures and hyperproliferative marrow. Although the GF/R rate after myeloablative HLA-matched sibling transplants for thalassemia has been reduced, its incidence still remains high following alternative donor transplantation. Typically, GF/R after HCT for thalassemia is accompanied by autologous hematopoietic recovery, but occasionally patients develop GF with prolonged marrow aplasia. Given great variability in conditioning regimens and outcomes after second HCT for GF/R, it is important to develop a uniform treatment approach to patients receiving second transplantation for GF/R with autologous recovery.Methods. We report on 21 consecutive patients with median age of 9 years (range, 4-24 years) with thalassemia who underwent a second HCT for GF/R with autologous recovery. Ten patients had primary and 11 patients secondary GF/R following the first BMT. Median time to second transplant was 41 months (range, 8- 204). Treatment protocol consisted of preconditioning cytoreduction/immunosuppression with hydroxyurea (30 mg/kg/day) and azathioprine (3 mg/kg/day) from day −45 pre-transplant, and fludarabine (30 mg/m2/day) from day −16 through day −12. Conditioning regimen included oral or intravenous (i.v.) busulfan, thiotepa 10 mg/kg/day, cyclophosphamide 200 mg/kg total dose, and thymoglobulin 12.5-10 mg/kg total dose. Cyclosporine, methylprednisolone and methotrexate were given for GVHD prophylaxis. All but 4 patients received second HCT from the same donor. Thirteen patients received bone marrow (BM), and 8 patients PBSC. One patient was in class 1, 7 patients in class 2, and 13 patients in class 3 of risk. Most patients had moderately severe iron overload with median serum ferritin of 2692 ng/ml (range, 500-10126 ng/ml). The median liver fibrosis score 1 (range 0-5).Results. All but 1 patient achieved sustained engraftment with a 5 year overall and disease-free survival (DFS) of 85% (95% CI, 59-95%). DFS was 92% (95% CI, 54-99%) in patients receiving BM and 75% (95% CI, 32-93%) in those given PBSC, although the difference was not statistically significant (p=0.27) (Figure 1).One patient had primary GF with the cumulative incidence of 5% (95% CI, 0-13%). The incidence of grade 2-4 acute GVHD was 50% (95% CI, 0-75%) in the PBSC and 8 % (95% CI, 0-24%) in the BM group (p=0.025). Respective incidences of moderate to severe chronic GVHD were 43% (95% CI, 0-70%) and 0% (p=0.012). The high incidence of both acute and chronic GVHD after PBSC transplantation prompted us to abandon its use for second transplantation since 2006. At the time of survival analysis, 18 patients were alive, with median follow-up duration of 10 years (range, 1.2-12.8 years). At present all patients are off immunosuppressive medication. There were 3 deaths due to pneumonia, postsplenectomy sepsis and rejection with cerebral bleeding. The most frequently observed toxicities were grade 2 elevations in AST and ALT, followed by grade 2 oral mucositis. Few patients experienced grade 3 liver and gut toxicities. None of the patients developed liver VOD. Three patients had pneumonia, and 4 patients developed grade 2-3 late onset BK virus -related hemorrhagic cystitis. None of the patients developed lymphoproliferative disorder.Conclusions. We demonstrate the excellent DFS in patients with thalassemia treated with second transplantation for GF/R following the first graft. Importantly, the intensified treatment protocol was not associated with increased nonhematological toxicity, even though most patients suffer from pre-existing organ damage due to iron overload and/or hepatitis. This study clearly showed that the same donor could be successfully used for second transplantation in these patients. Due to significantly high incidence of both acute and chronic GVHD after PBSC, bone marrow graft is preferred source for second transplantation in patients with thalassemia. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Effective Strategy to Prevent Acute Graft-Versus-Host Disease in Unrelated Donor Allogeneic Hematopoietic Cell Transplants By Using a Combination of Anti-Thymocyte Globulin (ATG), Post-Transplant Cyclophosphamide and Cyclosporine

Introduction:Acute Graft-versus-Host Disease (aGVHD) is a frequent complication of Allogeneic Hematopoietic cell transplants (allo-HCT); aGVHD, especially Grade III-IV, can be lethal with increased morbidity and mortality and can occur in upto 40-50% of allo-HCT. GVHD prophylaxis has been used for control of GVHD, with use of calcineurin inhibitors, anti-metabolites and anti T cell antibodies. Use of Post-transplant Cyclophosphamide (PTCy) has recently been used extensively in haplo-identical transplant setting with promising results. However, PtCy has mainly been used in patients with BM as the stem cell source. In those patients with PBSC as the stem cell source, alone PTCy has been associated with clinically significant acute and chronic GVHD. As most of our patients use PBSC as the graft source, we hypothesized to combine both ATG and PTCy to reduce incidence of both acute and chronic GVHD in our patient cohort. Here we present a small cohort data using a combination of all these agents to effectively reduce aGVHD in hematological malignancies..Methods:A total of 28 patients with hematological malignancies, who had an unrelated donor underwent allo-HCT at our center from 1 Oct 2015 to 31 Mar 2016. The characteristics of the patients are summarized in Table 1. The conditioning regimen was either myeloablative (MAC, namely FBT400) or Reduced Intensity (RIC, namely FBT200) in patients with age ≤ 60 and >60 years, respectively. After interim analysis when increased non-hematological toxicity was observed in the MAC arm, all patients subsequently received FBT 200 conditioning. Peripheral blood was used as the stem cell source in all patients. Filgrastim was used from day +7 onwards for 13 patients. Special emphasis was given to incidence of acute GVHD, infections, regimen related toxicities and engraftment.Results:Out of total of 28 patients, aGVHD was seen in only 6 (21.4%) patients, five of which had skin involvement (Grade I-II) and one suspected liver involvement (Grade III), all of which responded rapidly to steroids. However, we did observe increased toxicities such as sinusoidal obstruction syndrome (32%), bacterial infections (68%) and viral infections (46%; CMV reactivations in 64%). Primary disease relapse, secondary graft failure and EBV reactivations were seen in 10% of cases, with documented Post Transplant Lymphoproliferative Disorder (PTLD) in only 2 patients. The overall survival of the entire cohort was 67.8% with a median duration of 6 months (range; 3-8 months). In comparison to MAC, RIC regimen was found to be superior with no Gr III-IV aGVHD, less toxicity and improved survival (RIC-82% vs MAC-45%).Conclusions: Combination of ATG-PTCy-CsA is an effective strategy to reduce aGVHD in unrelated donor transplants, albeit with moderate increase in toxicities. RIC with this combination was associated with less organ damage and superior survival. However, a long term follow up is needed to assess relapse and cGVHD. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Outcomes for Allogeneic Hematopoietic Cell Transplantation for AML and High-Grade MDS in Older Adults in the Era of T-Replete Haploidentical Donor Grafts. a Single Center Multivariate Analysis

Introduction: Outcomes for non-transplant therapy in older adults (age> 60 years) with AML or high-grade MDS have historically been poor. Allogeneic hematopoietic cell transplantation (allo-HCT) may improve these outcomes. However, many older patients will lack suitably HLA-matched sibling donors (MRD). Furthermore, many patients from ethnic minorities will lack an optimally matched unrelated donors (MUD). Additionally, the greater incidence and severity of chronic GVHD typically seen following MUD transplants may be particularly difficult to tolerate in older patients. T-replete haploidentical donor transplants (HAPLO) using post-transplant cyclophosphamide to mitigate alloreactivity may provide a suitable donor option for some older patients. However, no detailed comparison of outcomes after HAPLO to MRD and MUD donors in elderly patients with AML and high-grade MDS have been reported in the modern era..Methods: We analyzed outcomes of patients aged > 60 years with AML or high-grade MDS who received an allo-HCT at our center between 2005 and 2015. Ex-vivo T-cell depleted transplants and cord blood transplants were excluded. Supportive care measures were identical between the three donor groups. Patient characteristics and outcome parameters were extracted from our institutional database where they had been prospectively entered. Kaplan-Meier estimates of overall survival (OS) and disease-free survival (DFS) were calculated and the cumulative incidence method with competing risks was used to calculate rates of non-relapse mortality (NRM) and relapse. Cumulative incidences of acute and chronic GVHD were estimated with death being treated as the competing risk. Cox proportional hazards models, stratified on the three transplant donor groups, were developed using OS, DFS, NRM and relapse as endpoints and other parameters as covariates. GVHD was prospectively documented by a single dedicated nurse using established criteria including NIH consensus criteria for chronic GVHD and rates calculated using the cumulative incidence method.Results: Patient characteristics (n=127, 33 HAPLO, 37 MRD, 57 MUD) were as follows: median age 64 (60-77); male 57%; regimen- myeloablative (24%) non-myeloablative (76%); graft- PBSC (80%) BM (20%); Diagnoses- AML 59%, MDS 41%; DRI- low (2%), intermediate (58%), high (39%), very high (1%); Sorror HCT-comorbidity index 0-2 (46%), >3 (54%); Median HLA mismatches were 5/10 (range 2/10 to 5/10) for HAPLO patients. Estimated rates of OS, DFS, NRM and relapse for the entire group at 2 years were 60%, 49%, 18%, and 33%. When compared to MRD and MUD, HAPLO patients had similar characteristics but were less likely to have myeloablative conditioning (6% vs. 32% and 30% respectively for MRD and MUD, p=0.016) and were more likely to have a BM graft (52% vs. 0% and 21%, p<0.001). Median follow-up of surviving patients following MRD, MUDT and HAPLO transplants were 34m, 26m and 17m. For MRD, MUD, and HAPLO transplants respectively, estimated outcomes are as follows: TRM at 1year: 14%, 14% and 9% and 2yrs 17%, 23%, 9%, Relapse at 1year - 25%, 34%, 22% and 2 yrs -32%, 34%, 33%; OS at 1 yr 72%, 72%, 77% and 2 yrs - 62%, 55% , 67%. DFS at 1 yr - 61%, 52%, 69% and 2 yrs - 51%, 43%, 58% (Fig 1.) (p=NS for all endpoints on pointwise and global comparison). The cumulative incidences of acute GVHD at 180 days were: grade 2-4 - 27%, 37% and 39%; grade 3-4 - 8%, 18% and 15% (p=NS for all) and chronic GVHD at 2 yrs were: moderate to severe - 38%, 35%, 15% (p=0.028 MUD vs HAPLO, p=0.026 MRD vs HAPLO); severe - 12%, 11%, 0% (p=0.030 MUD vs HAPLO, p=0.009 MRD vs HAPLO). On multivariable Cox analysis, donor type was not a significant predictor of OS, DFS, NRM or relapse (Table 1).Conclusions: The results show that in the current era, using predominantly non-myeloablative conditioning regimens, 2 year OS and DFS rates of 60% and 49% with a NRM <20% can be achieved in patients aged >60 years who undergo allo-HCT for AML and high-grade MDS. Outcomes of patients transplanted from HAPLO donors are comparable to those from matched donors although the rate of clinically significant chronic GVHD appears significantly less following HAPLO transplants, which may translate to an improved quality of life. [Display omitted] [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

An EBMT Prospective Non-Interventional Study of Outcomes and Toxicity of Allogeneic Stem Cell Transplantation in Chronic Myeloid Leukemia Patients Previously Treated with Second Generation Tyrosine Kinase Inhibitors

Introduction: Allogeneic stem cell transplantation (SCT) remains a treatment option for patients with chronic myeloid leukemia (CML) that fail to respond to tyrosine kinase inhibitors (TKI). While the use of Imatinib seems to have no adverse impact on outcomes after transplant, little is known on the effects of prior use of second generation TKI (2GTKI). We present the results of a prospective non-interventional study (NIS) performed by the European Group for Blood and Marrow Transplantation (EBMT) of all consecutive allogeneic SCT for patients diagnosed with CML from 2009 to 2013.Methods: A prospective follow up of pre and post-transplant data was carried out by the EBMT Leiden office, including TKI therapy data, MED-B and a specific MED-C post transplant data. A total of 94 EBMT centers from 32 countries included 437 patients.Results: We present the results of the 383 patients that fulfilled all the inclusion criteria and had median follow-up of 37 months (1-77). The median age was 45 years (18-68) and 251 (65%) were males. Disease status at the start of 2GTKI was: First chronic phase - CP1 (123, 46%), Accelerated phase or >CP1 (67, 25%) and blast crisis (75, 28%). The choice of 2GTKI was: Dasatinib (155, 40%), Nilotinib (64, 17%) and a sequential combination of Dasatinib/Nilotinib with or without Bosutinib/Ponatinib (164, 43%). In addition, 29% of patients that received Dasatinib were in CP1 at the start of 2GTKI and at the time of SCT compared with 45% at the start and 40% at SCT for patients treated with Nilotinib. For patients that received both TKI in sequential combination, 63% were in CP1 at the start of 2GTKI but only 46% reached the SCT in CP1. Overall disease status at SCT was CP1 in 139 patients (38%), AP in 163 (45%) and BC in 59 (16%).The median interval from diagnosis to SCT was 22 months (2 - 267) and the median interval between starting 2GTKI and SCT was 10 months (1 - 191). The donor was an HLA identical sibling in 130 cases (35%) and unrelated in 244 (65%). The majority of SCT were performed using PBSC (295, 77%), while 272 (71%) were myeloablative and 111 (29%) reduced intensity conditioning. The EBMT score was low (0-2) in 26 (7%), intermediate (3-4) in 216 (62%) and high (5-7) in 107 (31%). Primary graft failure (PGF) occurred in 10 (3%) cases, while the incidence of acute GVHD was 34% (95% CI 29-39) and chronic GVHD (CGVHD) was 60% at 5 years (95% CI 54-66). CGVHD occurred at a median of 5.7 months (3-61) post SCT. Other post SCT complications included veno-occusive disease of the liver (VOD) in 6 cases (2%) and severe infection in 195 (65%). There were no differences in post-transplant complications amongst the 3 different 2GTKI subgroups. Overall non-relapse mortality was 18% (95% CI 14-22) at 12 months and 24% (95% CI 19-29) at 5 years. Relapse incidence was 36% (95% CI 29-42), overall survival was 56% (95% CI 50-62) and relapse-free survival was 40% (95% CI 33-47) at 5 years. Overall survival was 67% (95% CI 59-75) at 5 years for patients in CP1. No differences in post-transplant outcomes were found amongst the 3 different 2GTKI subgroups. However, the EBMT score, performance status and disease stage at 2GTKI and at SCT were predictive of overall and progression-free survival.Discussion: This prospective study demonstrates the feasibility of performing allogeneic SCT in CML patients previously treated with 2GTKI. The rate of post-transplant complications including graft failure, VOD, infections, GVHD and non-relapse mortality seems comparable to that of patients treated with Imatinib or TKI-naïve. We observed no differences between outcomes for patients receiving Dasatinib, Nilotinib or any other combination of 2GTKI (including Bosutinib and Ponatinib) pre-SCT. However, patients receiving Dasatinib were more likely to proceed to SCT in advanced phase than in CP1. Patients in CP1 have a very good overall survival despite prior treatment with 2GTKI. Of note, even after 2GTKI, the EBMT score remains a strong predictor of overall and disease-free survival for CML patients undergoing allogeneic SCT. [Display omitted] [Display omitted] DisclosuresSchouten:Sanofi: Consultancy; Novartis: Consultancy. de Witte:Novartis: Honoraria, Research Funding; Celgene: Consultancy; Incyte: Consultancy. Kröger:Neovii: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Riemser: Honoraria, Research Funding; Novartis: Honoraria, Research Funding.