High-intensity Conditioning Regimens Research Articles

Subjective Oral Dryness following Hematopoietic Cell Transplantation: A Report from the Orastem Study

Xerostomia, or subjective oral dryness, is a serious complaint after hematopoietic cell transplantation (HCT). Xerostomia is rated as one of the most bothersome symptoms by HCT recipients, negatively affecting quality of life. This substudy of the Orastem study, a prospective longitudinal, international, observational, multicenter study, aimed to describe the prevalence and severity of xerostomia following HCT. Furthermore, the effect of the conditioning regimen, type of transplantation, and oral mucosal changes related to chronic graft-versus-host disease (cGVHD) in the development of xerostomia were studied. All HCT recipients rated xerostomia on a scale of 0 to 10 before the conditioning regimen, several times early post-HCT, and at 3 months post-HCT, and only allogeneic HCT recipients also rated xerostomia at 6 and 12 months post-HCT. In addition, stimulated whole mouth saliva was collected several times. Linear regression models and longitudinal mixed-effects models were created to investigate the influence of risk indicators on xerostomia. A total of 99 autologous and 163 allogeneic HCT recipients were included from 6 study sites in Sweden, Canada, the Netherlands, and the United States. The prevalence of xerostomia was 40% before the conditioning regimen, 87% early post-HCT, and 64% at 3 months post-HCT. Complaints after autologous HCT were transient in nature, while the severity of xerostomia in allogeneic HCT recipients remained elevated at 12 months post-HCT. Compared to autologous HCT recipients, allogeneic HCT recipients experienced 1.0 point more xerostomia (95% confidence interval [CI], .1 to 2.0) early post-HCT and 1.7 points more (95% CI, .4 to 3.0) at 3 months post-HCT. Allogeneic HCT recipients receiving a high-intensity conditioning regimen experienced more xerostomia compared to those receiving a nonmyeloablative or reduced-intensity conditioning regimen. The difference was 2.0 points (95% CI, 1.1 to 2.9) early post-HCT, 1.8 points (95% CI, .3 to 3.3) after 3 months, and 1.7 points (95% CI, .0 to 3.3) after 12 months. Total body irradiation as part of the conditioning regimen and oral mucosal changes related to cGVHD did not significantly influence the severity of xerostomia. Conditioning regimen intensity was a significant risk indicator in the development of xerostomia, whereas total body irradiation was not. Allogeneic HCT recipients experienced more xerostomia than autologous HCT recipients, a difference that cannot be explained by a reduction in stimulated salivary flow rate or the development of oral mucosal changes related to cGVHD.

Chip-Derived Vs De Novo Treatment-Related Myeloid Neoplasms after Autologous Stem Cell Transplant for Lymphoid Disorders

Autologous stem cell transplant (ASCT) involves high intensity conditioning regimens with significant cytotoxicity. Therapy-related myeloid neoplasms (tMN) represent a serious complication characterized by high-risk features and poor treatment outcomes in patients potentially cured from their primary neoplastic disorders. While the 2016 WHO classification broadly divides tMN into MDS or AML, yet their heterogeneity warrants a more distinctive characterization based on specific prior exposures and subsequently-developed unique features, as emphasized by the updated 2022 WHO revision. We previously analyzed the genomics of tMN including features suggestive of their derivation from either CHIP or de novo driver mutations1. Specifically for tMN pathobiology, ASCT may be very instructive due to the high dose therapy and repopulation of the hematopoiesis out of a limited number of transplanted hematopoietic stem cells. Post-ASCT tMN may be unique and possibly related to antecedent CHIP, CHIP induced by the procedure, or driver lesions. We took advantage of a large volume of ASCT performed at our institution along with excellent clinical annotations and long follow up to study the dynamics of tMN in this setting. We accrued a total of 1507 patients undergone ASCT, of whom 35 (2.3%) developed tMN at a median follow up time of 5.4 years following the procedure. The clinical and molecular phenotype of these index cases were then compared to a cohort of tMN patients (n=263) without prior history of ASCT. Of note, both groups had similar MDS/AML proportions. Compared to the rest of the ASCT cohort, patients developing tMN were older at the time of the transplant procedure (66 vs 46% ≥60 years, P=.02) and had a higher male preponderance (91 vs 59%, P<.0001). Post-ASCT tMN was more common following non-Hodgkin's lymphoma (NHL) than multiple myeloma (MM) (2.5 vs 1.1%, P=.0002) but similar between NHL and Hodgkin's disease (2.5 vs 1.5%, P=0.13). We then studied whether graft size and mobilization regimens could increase the risk of tMN. The incidence of this complications was higher with a mobilization involving GCSF (G), Etoposide (E) and Plerixafor (P) (GEP) rather than G, G+E or G+P (P=.0001), as well as when a CD34+ dose ≤3.5 x106 (4.1 vs 1.9%, P=.03) was infused. No difference was noted with respect to time to engraftment following ASCT. Multivariate analysis confirmed the independent influence of age ≥60 (HR 2.4, 95% CI 1.1-5.6), male sex (HR 7.1, 2.5-29.9), diagnosis (prior NHL vs MM; HR 3.3, 1.5-8.2) and mobilization scheme (GEP vs G+P; HR 4.7, 1.3-13.7). The caveat was the lack of significant effect of the graft size on tMN risk. When compared to non-transplanted cases, tMN following ASCT still showed a male preponderance (91 vs 51%, P<.0001) and exhibited a higher prevalence of high-risk (IPSS-R>3.5) MDS (79 vs 57%, P=.05). Furthermore, tMN arising post-ASCT appeared to follow a more aggressive course with a significantly shorter latency duration following the procedure (median 2.6 vs 6.5 years, P<.0001) and shorter overall survival (median 16 vs 58 months, P<.0001; Fig1). Cytogenetic profiling revealed higher frequencies of complex karyotype (49 vs 31%, P=.05), del(5q)/5- (26 vs 20%, P=.5), del(7q)/7- (46 vs 27.5%, P=.03), and del(17p)/17- (27 vs 6%, P=.0025) in the ASCT-exposed as opposed to non-transplanted cases. Subsequent analysis of isolated cytogenetic aberrations showed that isolated del(7q)/7- was significantly enriched in post-ASCT tMN (20 vs 6%, P=.0129). Mutational analysis revealed similar patterns with the exception of TP53, which was significantly more frequent in the ASCT-exposed group (41 vs 13%, P=.0028), mostly displaying a multi-hit configuration (32 vs 11%, P=.0178). We have previously shown that ancestral hits in DNMT3A, TET2, ASXL1 and JAK2 (CHIP-mutations) indicate derivation of disease from CHIP vsU2AF1, RUNX1 and STAG2 highlighted de novo cases, thereby prompting us to investigate whether CHIP may have been the originator of tMN post ASCT2. However, the frequencies of CHIP- and de novo -mutations were similar across the post-ASCT tMN and the non-ASCT tMN groups. Interestingly, within the post-ASCT tMN, patients who had CHIP-derived tMN had lower survival compared to the rest of the group (median 9 vs 25 months, P=.0079). Sequencing experiments on serial specimens are ongoing to determine whether CHIP- derived mutations were present prior to ASCT constituting a risk for tMN. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Glucagon-Like Peptide-1 Is Associated With Systemic Inflammation in Pediatric Patients Treated With Hematopoietic Stem Cell Transplantation.

Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are challenged with severe side effects, which are propagated by mucosal barrier disruption, and the related microbial translocation and systemic inflammation. Glucagon-like peptide-1 (GLP-1), a well-known incretin hormone, possesses anti-inflammatory properties and promotes regeneration of damaged intestinal epithelium in animal studies. We hypothesized that the immense inter-individual variation in the degree of mucosal damage and systemic inflammation, seen after HSCT is influenced by endogenous GLP-1 and could be related to acute post-transplant complications. In this prospective study we measured serial weekly fasting plasma GLP-1, along with C-reactive protein (CRP), and citrulline in 82 pediatric patients during allogeneic HSCT together with a fasting plasma GLP-1 in sex- and age-matched healthy controls. Overall, GLP-1 levels were increased in the patients during the course of HSCT compared with the controls, but tended to decrease post-transplant, most pronounced in patients receiving high-intensity conditioning regimen. The increase in CRP seen in the early post-transplant phase was significantly lower from day +8 to +13 in patients with GLP-1 above the upper quartile (>10 pmol/L) at day 0 (all P ≤ 0.03). Similar findings were seen for peak CRP levels after adjusting for type of conditioning (-47.0%; 95% CI, -8.1 – -69.4%, P = 0.02). Citrulline declined significantly following the transplantation illustrating a decrease in viable enterocytes, most evident in patients receiving high-intensity conditioning regimen. GLP-1 levels at day 0 associated with the recovery rate of citrulline from day 0 to +21 (34 percentage points (pp)/GLP-1 doubling; 95% CI, 10 – 58pp; P = 0. 008) and day 0 to day +90 (48 pp/GLP-1 doubling; 95% CI, 17 – 79pp; P = 0. 004), also after adjustment for type of conditioning. This translated into a reduced risk of acute graft-versus-host disease (aGvHD) in patients with highest day 0 GLP-1 levels (>10 pmol/L) (cause-specific HR: 0.3; 95% CI, 0.2 – 0.9, P = 0.02). In conclusion, this study strongly suggests that GLP-1 influences regeneration of injured epithelial barriers and ameliorates inflammatory responses in the early post-transplant phase.

Long-term follow-up of patients with poor-risk acute leukemia treated on a phase 2 trial undergoing intensified conditioning regimen prior to allogeneic hematopoietic cell transplantation

Patients with acute leukemia who undergo allogenic hematopoietic cell transplantation with active disease have high rates of relapse and poor overall survival (OS) post-transplant compared to patients undergoing HCT in remission. Here, we report the long-term outcomes in 32 patients who received a high-intensity conditioning regimen comprising fractionated total body irradiation (FTBI; 1200 cGy) with pharmacokinetic (PK) dosing of intravenous Busulfan (IV BU) targeted to first dose area under curve (AUC) of 700–900 µM/min and etoposide (30 mg/kg) in a prospective phase 2 clinical trial. The median age of the patients at the time of HCT was 37 years (range: 18–50) presenting with high-risk (n = 6) and relapsed/refractory(r/r) acute leukemias (n = 26). All but one patient underwent HCT using peripheral blood stem cells from matched sibling donors. At a median follow-up of 17.3 years (range 14.4–19.0), 11 patients remained alive. The disease-free survival and OS at 15 years was 34% (versus 40% at 5-years post-HCT). The 15-year cumulative incidence of relapse was 26% and non-relapse mortality (NRM) was 38% (95% CI: 21–54%) and the cumulative incidence of chronic GVHD at 15 years was 33% using a prophylactic regimen of cyclosporine A and mycophenolate mofetil. The most common life-threatening late effects were secondary malignancies, metabolic, or cardiac complications with a cumulative incidence of 6.6%, 6.6%, and 13.3%, respectively. No unusual late effects or patterns of relapse were noted on longer followed on patients treated with intensified myeloablative condition regimen. Results from this study supports continued development of intensive conditioning regimens in patients with r/r acute leukemias to improve leukemia free (LFS) and OS in this high-risk population.

Low-Toxicity/High-Efficacy HLA Haploidentical Transplantation for Elderly/Unfit Patients with Acute Leukemia

Allogeneic hematopoietic transplantation is the most powerful therapy for patients with acute leukemia at high risk of relapse. For HLA haploidentical transplantation, we recently applied a protocol consisting of a high-intensity TBI-based conditioning regimen and a peripheral blood CD34+ hematopoietic stem cell graft combined with the adoptive transfer of naturally occurring regulatory T cells (Tregs) and conventional T cells (Tcons). No post-transplant pharmacologic immune suppressive GvHD prophylaxis was given. Such a protocol was associated with remarkably low GvHD and relapse rates (Martelli MF et al., Blood. 124:638-644, 2014; reviewed in Mancusi A et al., Blood 128:2616-2623, 2016).However, patients who are unfit (because of multiple chemotherapy cycles, previous transplants, infections, or co-morbidities) or elderly are not expected to withstand high-intensity conditioning regimens. For these patients, we developed a reduced-toxicity version based on total marrow and total lymphoid irradiation (TMI/TLI) (Rosenthal J et al., Blood. 2011;117:309-315). TMI/TLI (13.5 Gy and 11.5 Gy respectively) were administered by means of Helical Tomotherapy HI-ART (in 9 fractions delivered two times a day in 4 and a half days). Target volumes were defined as the skeletal bone and major lymph node chains and spleen. In patients with ALL the brain was added as target volume. TMI/TLI was followed by chemotherapy with Thiotepa (2,5mg/kg/day for 2 days), Fludarabine (30 mg/m2/day for 5 days) and Cyclophosphamide (15 mg/kg/day for 2 days). As per our high-intensity protocol, the hematopoietic stem cell graft was foregone by an infusion of 2x10e6/Kg freshly isolated CD4/CD25/FOXP3-positive Tregs and a subsequent infusion of 1x10e6 Tcons. No post-transplant pharmacologic immune suppressive GvHD prophylaxis was given. To date 19 patients with high-risk acute leukemia in remission were enrolled (16 AML, 3 ALL). Median age was 57 years (range: 22-68). All patients engrafted. Four patients developed aGvHD grade ≥ 2. Transplant-related mortality was 21% (2 patients died of infections, 1 of VOD and 1 of aGvHD). Remarkably, no relapse or cGvHD were observed. With a median follow up of 12 months (range: 1-24), 15 of the 19 patients are alive. Thus, leukemia/cGvHD-free survival is 79%. Of course, these data need to be confirmed in a larger cohort of patients and with longer follow up.In conclusion, the present transplantation protocol was designed to make HLA haploidentical transplantation feasible and effective for unfit or elderly patients with high-risk leukemia. It combines a reduced-toxicity conditioning regimen with safe cellular immunotherapy of leukemia. To date, the clinical results are excellent and extremely encouraging. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Recent advances in allogeneic hematopoietic cell transplantation for acute myeloid leukemia.

Allogeneic hematopoietic cell transplantation (HCT), with associated graft-versus-leukemia effects, remains the best postremission strategy for patients with intermediate or high-risk acute myeloid leukemia (AML), with a curative potential. Here, we highlight recent advances in allogeneic HCT that broadened access, refined prognostication, and improved outcomes of AML patients undergoing this procedure. Eligibility for allogeneic HCT continued to expand to AML patients older than 60 years, as well as to patients lacking human leukocyte antigen (HLA)-matched donors with the advent of alternative donor sources, such as umbilical cord blood and HLA-haploidentical transplantation. Molecular profiling of AML has redefined prognostication for patients in specific AML genomic subgroups undergoing allogeneic HCT and has served as a new strategy for measuring minimal residual disease before and after allogeneic HCT. Using high intensity conditioning regimens has emerged as a potential strategy to reduce risk of relapse and improve overall survival, especially in patients with minimal residual disease prior to allogeneic HCT. As access to allogeneic HCT continues to improve, also, with more refined prognostic strategies, the field continues to move to optimize transplantation approaches by decreasing the risk of relapse and minimizing transplant-related complications.

Comparison of Outcomes between HSCT Donor Sources for Pediatric Patients with Hematologic Malignancies

Background: Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for pediatric patients with hematologic malignancies. Historically, matched sibling donors (MSD) have been the preferred donor source given ease of availability and lower rates of graft-versus-host-disease (GVHD). However, only 30% of patients have a MSD and relapse rates are high after MSD HSCT, raising the question of best donor choice. As conditioning regimens evolve, GVHD management improves and supportive care advances, it is important to evaluate the role of donor source on short and long-term clinical outcomes to inform donor selection. We performed a single-center retrospective analysis comparing post-HSCT outcomes in a cohort of pediatric patients undergoing MSD, matched unrelated donor (MUD), and umbilical cord blood (CB) transplants from 2006 to 2018. Methods: A retrospective analysis was performed on an IRB-approved protocol through Fred Hutchinson Cancer Research Center. 232 patients were included who received MSD (n=56), MUD (n=89) or CB (n=87) transplants. Of note, 24 CB patients received expanded CB cells in addition to unmanipulated unit(s). GVHD prophylaxis in all patients consisted of a calcineurin inhibitor and MMF or methotrexate. The vast majority received a high-intensity conditioning regimen (86%, 96%, and 82% respectively for MSD, MUD and CB). Overall survival (OS) and disease-free survival (DFS) were evaluated using the Kaplan-Meier method. Probabilities of non-relapse mortality (NRM), relapse, and acute GVHD were evaluated using cumulative incidence (CI) estimates with appropriate competing risks. The Cox regression model was used for adjusted analysis for age, year of transplant, sex, CMV status, MRD status, disease risk, and conditioning regimen. Results: Patient/treatment/donor demographics are shown in Table 1. Median follow-up was 2.6, 3.7 and 3.1 years for MSD, MUD and CB respectively. Patient diagnosis, disease risk, gender, age, and CMV serology were balanced between groups. CI of engraftment was similar as well, with only one graft failure in the MUD group (Fig 1). Median time to platelet recovery was significantly faster in MUD and MSD groups as compared to the CB group (p&lt;0.0001; p&lt;0.0001). There was no difference in unadjusted 5 year OS (Fig 2) and NRM (Fig 3) between groups. Five-year DFS was significantly higher in CB v. MSD (71% v. 54%, p=0.03) but not between CB v. MUD (71% v. 61%, p=0.18) or between MSD and MUD (p=0.38) (Fig 4). The CI of relapse at 5 years was 20% for CB patients, significantly lower than that of MSD recipients (49%, p=0.003) and not different from MUD (32%, p=0.11) (Fig 5). After adjusted analysis, the risk of DFS failures was higher among recipients of MSD than CB [HR: 1.88 (CI 95%: 1.01-3.47), p=0.04]. When CB versus MUD groups were compared, there was a trend of higher risk of DFS failures in the MUD group [HR: 1.28 (CI 95%: 0.96-1.66), p=0.09]. No difference was observed in risk of DFS failures between MSD versus MUD groups [HR:0.77 (CI 95%: 0.44-1.4), p=0.43]. Incidence of grade II-IV acute GVHD was 90% (95%CI: 82-95%), 75% (95%CI: 61-84%) and 88% (95%CI: 80-94%), for CB, MSD and MUD, respectively (p=0.25). Incidence of grade III-IV acute GVHD was 33% (95%CI: 23-43%) for CB, 9% (95%CI: 3-18%) for MSD, and 11% (95%CI: 5-18%) for MUD. Incidence of grade III-IV was significantly higher for the CB group compared to the other groups (p=0.001); however, nearly 60% of CB recipients with grade III-IV acute GVHD were diagnosed before engraftment had occurred and in retrospect met criteria for pre-engraftment syndrome. Among surviving patients, 23 CB recipients developed chronic GVHD (26% - 15 mild, 4 moderate, 4 severe) as compared to 14 MSD patients (25% - 13 mild, 1 moderate) and 40 MUD patients (45% - 27 mild, 11 moderate, 2 severe). Conclusions: Our data demonstrate no difference in unadjusted OS between MSD, MUD and CB recipients. Importantly, despite this equivalence, 5-year DFS was significantly better in the CB v. MSD group, reflecting the lower relapse rate observed in CB patients and seen previously by us and others. CB continues to be viewed as an "alternative" donor for HSCT due to the low stem cell dose in a CB graft resulting in delayed neutrophil recovery, primary graft failure and increased NRM. However, this was not observed herein, supporting the use of CB for pediatric HSCT perhaps especially in patients at high risk of post-transplant relapse. Disclosures Milano: ExCellThera: Research Funding; Amgen: Research Funding. Delaney:Nohla Therapeutics: Employment, Equity Ownership; Biolife Solutions: Membership on an entity's Board of Directors or advisory committees. Bleakley:HighPass Biotherapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents &amp; Royalties, Research Funding.

Early Organ Toxicity Following Allogeneic Hematopoietic Stem Cell Transplantation Differs By Conditioning Regimen

Background: In recipients of allogeneic hematopoietic stem cell transplantation (HSCT), organ toxicity is a barrier to administering high-intensity conditioning regimens. We hypothesized that determinants of acute organ toxicity are specific to individual conditioning regimens. We sought to characterize toxicities across common transplantation regimens, evaluate their prognostic implication, and derive predictors of severe toxicity at the regimen level. Methods: This retrospective study included adults undergoing first allogeneic HSCT at a single center between the years of 2001 and 2014 (median: 2010). Patients received grafts from matched sibling or unrelated donors and were conditioned with any of the following regimens: Cyclophosphamide + TBI (Cy/TBI), Busulfan + Cyclophosphamide (Bu/Cy), Fludarabine + 12.8 mg Busulfan (Flu/Bu4), Fludarabine + 6.4 mg Busulfan (Flu/Bu2), Fludarabine + 36-42 gr/m2 Treosulfan (Flu/Treo), and Fludarabine + 100-140 mg/m2 Melphalan (Flu/Mel). Toxicities were defined by the KDIGO scale for acute kidney injury (AKI) and by the CTCAE v. 5.0 for increases in total bilirubin, AST, ALT, and alkaline phosphatase (Alk. Phos.) The incidence of toxicities from the start of conditioning through 30 days post-transplantation was tabulated by regimen. Risk factors for severe organ toxicity were assessed within each regimen cohort using multivariable logistic regressions. Results: In a cohort of 707 patients, the median age was 52 years. The main indications for transplantation were acute leukemia (57%), myelodysplastic syndrome (13%), and aggressive lymphoma (9%). Graft-versus-host-disease prophylaxis included methotrexate in 80% of patients, and 56% received anti-thymocyte globulin (ATG). The most common regimens were Flu/Treo (n = 160) and Bu/Cy (n = 141). As expected, patient characteristics varied between regimens. The incidence of AKI and increased serum bilirubin in each regimen is shown in Figure 1A and 1B, respectively. Sinusoidal-obstructive syndrome (6% overall) accounted for only 17% of gr. ≥ 3 bilirubinemia in the entire cohort. Elevations in AST, ALT, and Alk. Phos of gr. ≥ 3 were not common (&lt;8%). In multivariable logistic regression, AKI gr. ≥ 2, increased bilirubin gr. ≥ 3, AST gr. ≥ 3, and Alk. Phos. gr. ≥ 2 were associated with increased 100-day mortality (p &lt; 0.05). Acute severe organ toxicity (ASOT) was defined as the occurrence of any of these toxicities. ASOT had an odds ratio (OR) of 3.4 (95% CI: 2.2-5.3) for 100-day mortality. Within each regimen, we studied the relationship between ASOT and transplantation/patient characteristics (Figure 1C). Elevations in baseline bilirubin were predictive of ASOT in Cy/TBI (OR: 1.68 [1.19-2.37]), while increasing creatinine was predictive in patients conditioned with Flu/Mel (OR: 1.43 [1.09-1.88]). High-risk disease (DRI) was associated with increased risk in patients receiving Flu/Bu4 (1.26 [1.01-1.58]). In patients treated with Bu/Cy, administration of ATG increased the risk of ASOT (1.31 [1.11-1.55]). Conclusion: Allogeneic stem cell transplantation recipients are at high risk for acute organ damage. We describe patterns of renal and liver toxicity across several regimens. Determinants of acute severe organ toxicity, defined as those associated with short-term mortality, are regimen dependent. Our findings suggest that these factors should be considered when selecting the preparative regimen. While requiring validation, the newly-defined composite endpoint of acute severe organ toxicity (ASOT) may be valuable in studying transplantation strategies. Figure 1 Disclosures No relevant conflicts of interest to declare.

Hematopoietic cell transplant for acute myeloid leukemia and myelodysplastic syndrome: conditioning regimen intensity

AbstractIn this study, we sought to identify specific individual high-intensity or reduced-intensity conditioning regimens with the best relapse-free survival (RFS) rather than the global high- vs reduced-intensity regimen comparison. Patients (median age, 58 years) with acute myeloid leukemia (AML; n = 1258), who were in first or subsequent remission, or with MDS (n = 951) who had refractory anemia with unilineage or multilineage dysplasia, 5q− syndrome, or refractory anemia with excess blasts received nonirradiation-containing regimens and were transplanted between 2009 and 2014 in the United States. Three-year RFS with high-intensity busulfan/cyclophosphamide (Bu4/Cy; 44%) was comparable to conditioning with high-intensity fludarabine/busulfan (Flu/Bu4; 44%), reduced-intensity fludarabine/melphalan (Flu/Mel; 52%; P = .53), and Flu/Mel + anti-thymocyte globulin (ATG; 44%; P = .38). RFS was lower with reduced-intensity Flu/Bu2 + ATG (31%; P = .0006). RFS was also lower with high-intensity Flu/Bu4 + ATG (38%; P = .05) and reduced-intensity Flu/Bu2 (38%; P = .02), although the difference did not reach the level of significance set for these analysis. RFS with Flu/Mel was superior to RFS with Flu/Bu2 (P = .01) and Flu/Bu2 + ATG (P = .0006). The 3-year incidence of relapse was 22% with Flu/Mel compared with 46% with Flu/Bu2 and 56% with Flu/Bu2 + ATG. With only a modest reduction in nonrelapse mortality with the Flu/Bu2 regimens, the higher relapse incidence resulted in lower RFS. The data support optimal RFS with Bu4/Cy, Flu/Bu4, and Flu/Mel regimens for AML in remission or MDS. The low relapse rate with reduced-intensity Flu/Mel resulted in RFS comparable to that after the higher-intensity regimens.

Chemotherapy-Based HLA Haploidentical Transplantation with Treg/Tcon Immunotherapy in Unfit/Elderly Leukemia Patients: Powerful Gvl Effect and Insights from Animal Models

In patients with acute leukemia (AL) at high risk of relapse, because of unfavorable cytogenetics, molecular markers and disease status, the most powerful therapy is hematopoietic stem cell transplantation. In HLA-haploidentical stem cell transplantation we showed adoptive immunotherapy with naturally occurring T regulatory cells (nTregs) followed by conventional T cells (Tcons) prevented graft-versus-host-disease (GvHD) (Di Ianni et al., Blood 2011) and was associated with low transplant-related mortality (TRM) and relapse rate (Martelli et al., Blood 2014) in patients with AL conditioned with single-dose TBI.However, patients that are heavily pretreated (e.g., because of multiple induction chemotherapy cycles, previous autologous or allogeneic transplant, previous irradiation, infections, etc.) and elderly patients are not expected to withstand a high-intensity TBI-based conditioning regimen. For these patients with an indication to transplant we, therefore, designed a chemotherapy only-based conditioning regimen. We enrolled 24 patients with high risk AL (19 AML and 5 ALL, median age: 46, range 21-64). Twenty-two patients were transplanted in CR and 2 in relapse. For 5 patients this was the second transplant. Patients received a conditioning regimen that included thiotepa (10 mg/Kg on days -10 and -9), fludarabine (200 mg/sqm from day -10 to -7) and melphalan (80-120 mg/sqm on day -5). Fiftheen patients also received ATG (6 mg/kg on days -24 and -23). Seven patients also received cyclophosphamide (20 mg/Kg on days -8 and -7) (and no ATG). Two patients received only Treosulfan (36 gr/sqm from day -8 to -6), fludarabine and thiotepa. On day -4 patients were received an infusion of 2x10e6/kg nTregs (93% ± 8 SD FoxP3+ cells). On day 0 they received CD34+ cells (mean 9.5x10e6/kg ±3.1 SD) and Tcons (1x10e6/kg). No post-transplant pharmacologic immune suppressive GvHD prophylaxis was given. Twenty-two of the 24 patients engrafted. CD4+ and CD8+ cell counts reached 200/µL on days 56 (range 30-100) and 35 (range 20-120) respectively with a wide T-cell repertoire as analyzed by Spectratyping. Eight of the 22 engrafted patients (36%) developed ≥ grade II acute GvHD. Three of the 8 patients died, 3 are alive with cGvHD and 2 are currently under immunosuppressive therapy. The incidence of TRM was 32% (7/22). Only one patient (in relapse at the time of transplant) relapsed. At a median follow-up of 24 months (range 5-44), 62% of the patients are alive and leukemia-free. The mechanisms underlying Treg suppression of GVHD with no loss of GVL activity were clarified by our murine transplant models. NSG mice received human myeloid or lymphoblastic leukemia and HLA mismatched Tregs/Tcons. Mice that received leukemia and Tcons (without Tregs) cleared leukemia but died of GvHD. Human T cells harvested from their bone marrow, liver and gut displayed a CD8+ phenotype and mediated alloreactivity against human leukemia. Mice treated with Tregs alone died of leukemia. No human T cells were found in their bone morrow. Human CD4+ T cells were instead recovered in the liver and gut. They had retained their regulatory function as they inhibited mixed lymphocyte reaction. Mice that received human leukemia and Tcons plus Tregs were rescued from leukemia and survived without GvHD. Human T cells harvested from liver and gut were composed of CD4+/FOXP3- T cells (60%) and CD8+ T cells (40%). Purified CD4+ T cells had retained their regulatory function as they inhibited mixed lymphocyte reaction. Purified CD8+ T cells displayed no alloreactivity against human leukemia. In contrast, human T cells harvested from bone marrow were still predominantly CD8+ and still displayed potent alloreactivity against human leukemia. In conclusion, peripheral blood Tregs used for adoptive immunotherapy were predominantly CD45RO+ (and negative for the bone marrow homing receptor CXCR4) and, when infused in mice, migrated to GvHD target organs (i.e., liver and gut) where they blocked Tcons and prevented GvHD. However, they were unable to migrate to the bone marrow, thereby allowing Tcons to exert unopposed alloantigen recognition and leukemia killing.These results demonstrate haploidentical transplantation with a chemotherapy-based conditioning regimen and Treg/Tcon immunotherapy is not only feasible in fragile patients but also exerts a powerful anti-leukemic effect. Apparently, the Treg/Tcon immunotherapy plays a key role in the GvL effect. DisclosuresPierini:Stanford University: Patents & Royalties.

Prospective Multicenter Phase II Study of Myeloablative Conditioning Consisted of Intravenous Busulfan and Fludarabine +/- Total Body Irradiation for Older Patients (55 years and older): Final Analysis of the JSCT FB09 Study

s / Biol Blood Marrow Transplant 20 (2014) S211eS256 S253 regimen consisting of busulphan, melphalan and fludarabine. All patients received ATG to prevent graft rejection. Donors were matched related (8) andmatched unrelated (4). BM grafts were depleted of T-cells using the soybean agglutinin method followed by sheep RBC rosetting, and PB grafts by immunomagnetic CD34+ selection (Isolex initially and CliniMACS after 09/2011). Results: Three pts died early and were not evaluable for engraftment, the remaining 9 pts engrafted. None of these pts developed acute or chronic GvHD after the primary graft. Of the 9 pts evaluable for long term follow up, 8 are alive with a median follow up time of 12.1 months (3.3-196months). One pt relapsed 15 months post initial transplant and achieved remission after DLI. This patient developed acute gut GVHD that responded to steroids. Two additional pts received low dose DLI (0.5x106CD3 cells/kg), one for recurrent viral infections and the other as prophylaxis for relapse. These 2 pts had no GvHD post-DLI. Out of the 4 pts who did not undergo pre-transplant splenectomy, one required post transplant splenectomy for severe persistent thrombocytopenia which resolved post splenectomy. JAK2 mutation was not detected post transplant in any of the 3 pts. In this small series of pts, eight out of twelve, 66%, are alive; two of the five pts in the subgroup cyto-reduced with TBI based regimen and six of the seven patients in the subgroup cyto-reduced with chemotherapy only regimen. The causes of death were: toxicity of the preparative regimen (TBI) in 2, intra-cranial hemorrhage in 1 and unknown in the 4 thpatient who died more than 2 years post transplant with no evidence of disease. Conclusions: TCD transplantation can offer long term cure for patients with advanced chronic MF and with no evidence of GvHD in this small cohort of patients. The early experience at MSKCCwith TCD transplant was associatedwith high rates of early mortality likely related to the high intensity conditioning regimen containing TBI. The current regimen of busulphan, melphalan, fludarabine and ATG has been well tolerated and the majority of pts are alive and disease free.

Analysis of repeated high-intensity running performance in professional soccer

The aims of this study were twofold: (1) to characterize repeated high-intensity movement activity profiles of a professional soccer team in official match-play; and (2) to inform and verify the construct validity of tests commonly used to determine repeated-sprint ability in soccer by investigating the relationship between the results from a test of repeated-sprint ability and repeated high-intensity performance in competition. High-intensity running performance (movement at velocities >19.8 km · h−1 for a minimum of 1 s duration) was measured in 20 players using computerized time–motion analysis. Performance in 80 French League 1 matches was analysed. In addition, 12 of the 20 players performed a repeated-sprint test on a non-motorized treadmill consisting of six consecutive 6 s sprints separated by 20 s passive recovery intervals. In all players, most consecutive high-intensity actions in competition were performed after recovery durations ≥61 s, recovery activity separating these efforts was generally active in nature with the major part of this spent walking, and players performed 1.1 ± 1.1 repeated high-intensity bouts (a minimum of three consecutive high-intensity bouts with a mean recovery time ≤20 s separating efforts) per game. Players reporting lowest performance decrements in the repeated-sprint ability test performed more high-intensity actions interspersed by short recovery times (≤20 s, P < 0.01 and ≤30 s, P < 0.05) compared with those with higher decrements. Across positional roles, central-midfielders performed more high-intensity actions separated by short recovery times (≤20 s) and spent a larger proportion of time running at higher intensities during recovery periods, while fullbacks performed the most repeated high-intensity bouts (statistical differences across positional roles from P < 0.05 to P < 0.001). These findings have implications for repeated high-intensity testing and physical conditioning regimens.

Influence of immunosuppressive treatment on risk of recurrent malignancy after allogeneic hematopoietic cell transplantation

AbstractThis study was conducted to elucidate the influence of immunosuppressive treatment (IST) and GVHD on risk of recurrent malignancy after allogeneic hematopoietic cell transplantation (HCT). The study cohort included 2656 patients who received allogeneic HCT after high-intensity conditioning regimens for treatment of hematologic malignancies. Rates and hazard ratios of relapse and mortality were analyzed according to GVHD and IST as time-varying covariates. Adjusted Cox analyses showed that acute and chronic GVHD were both associated with statistically similar reductions in risk of relapse beyond 18 months after HCT but not during the first 18 months. In patients with GVHD, resolution of GVHD followed by withdrawal of IST was not associated with a subsequent increase in risk of relapse. In patients without GVHD, withdrawal of IST was associated with a reduced risk of relapse during the first 18 months, but the risk of subsequent relapse remained considerably higher than in patients with GVHD. In summary, the association of GVHD with risk of relapse changes over time after HCT. In patients without GVHD, early withdrawal of IST might help to prevent relapse during the first 18 months, but other interventions would be needed to prevent relapse at later time points.

No improvement of survival with reduced- versus high-intensity conditioning for allogeneic stem cell transplants in Ewing tumor patients

BackgroundOutcomes of Ewing tumor (ET) patients treated with allogeneic stem cell transplantation (allo-SCT) were compared regarding the use of reduced-intensity conditioning (RIC) and high-intensity conditioning (HIC) regimens as well as human leukocyte antigen (HLA)-matched and HLA-mismatched grafts. Patients and methodsWe retrospectively analyzed data of 87 ET patients from the European Group for Blood and Marrow Transplantation, Pediatric Registry for Stem Cell Transplantations, Asia Pacific Blood and Marrow Transplantation and MetaEICESS registries treated with allo-SCT. Fifty patients received RIC (group A) and 37 patients received HIC (group B). Twenty-four patients received HLA-mismatched grafts and 63 received HLA-matched grafts. ResultsMedian overall survival was 7.9 months [±1.24, 95% confidence interval (CI) 5.44–10.31] for group A and 4.4 months (±1.06, 95% CI 2.29–6.43) for group B patients (P = 1.3). Death of complications (DOC) occurred in 4 of 50 (0.08) and death of disease (DOD) in 33 of 50 (0.66) group A and in 16 of 37 (0.43) and 17 of 37 (0.46) group B patients, respectively. DOC incidence was decreased (P < 0.01) and DOD/relapse increased (P < 0.01) in group A compared with group B. HLA mismatch was not generally associated with graft-versus-Ewing tumor effect (GvETE). ConclusionsThere was no improvement of survival with RIC compared with HIC due to increased DOD/relapse incidence after RIC despite less DOC incidence. This implicates general absence of a clinically relevant GvETE with current protocols.

A Retrospective Comparison of Tacrolimus versus Cyclosporine with Methotrexate for Immunosuppression after Allogeneic Hematopoietic Cell Transplantation with Mobilized Blood Cells

This retrospective study was performed to compare results with tacrolimus versus cyclosporine in combination with methotrexate for immunosuppression after allogeneic hematopoietic cell transplantation (HCT) with granulocyte colony-stimulating factor-mobilized blood cells. The cohort included 456 consecutive patients who received first allogeneic T cell-replete HCT with mobilized blood cells from related or unrelated donors after high-intensity conditioning for treatment of hematologic malignancies. Study endpoints included grades II-IV acute graft-versus-host disease (aGVHD), grades III-IV aGVHD, chronic GVHD (cGVHD), end of treatment for cGVHD, overall mortality, disease-free survival (DFS), recurrent malignancy, and nonrelapse mortality (NRM). Adjusted multivariate Cox regression analysis showed no statistically significant differences between tacrolimus and cyclosporine for any of the endpoints tested. Although the size of the cohort is not sufficient to exclude clinically meaningful differences in outcomes, these results support the continued use of cyclosporine at centers that have not adopted tacrolimus as the standard of care after HCT with mobilized blood cells after high-intensity conditioning regimens. A larger registry study should be performed to provide more definitive information comparing outcomes with the 2 calcineurin inhibitors.

Risk Factors for Mortality In Cytomegalovirus Infection After Hematopoietic Stem Cell Transplantation.

AbstractAbstract 4539 BACKGROUND:Cytomegalovirus (CMV) end-organ disease is a serious complication after allogeneic stem cell transplantation (Allo-SCT). Described risk factors for CMV infection are pretransplant CMV seropositive status of the recipient, non related donor or umbilical cord transplant, depleted lymphocyte graft, high intensity conditioning regimen, severe graft versus host disease (GVHD), CD34+ selection of the graft and delayed CMV specific immune reconstitution. OBJETIVES:To identify different profiles of allogeneic stem cell recipients based on their previously described risk factors for CMV infection and its association with their clinical outcomes. PATIENTS AND METHODS:A prospective study of consecutive recipients of Allo-SCT was performed from June 2008 through December 2009 at a single institution. Patients were sequentially monitored both clinically and analytically. CMV viral load was determined by real time PCR and CMV-specific T cell response was determined by flow cytometry. Non-normal distribution data were expressed as median values (range). Chi-square test or Fisher exact test were used to compare differences between groups of categorical data. Differences were considered statistically significant for p-values < 0.05. All statistical analyses were performed using SPSS 16.0 software (Chicago, IL). RESULTS:Twenty-six patients were included with a median age of 33 years (range:15-61). The donor was an identical sibling in 42.3%, unrelated donor in 53.8% and a mismatched family member in 3.8%. The source was peripheral blood 76.9%, cord blood 15.4% and bone marrow in 7.7%. Previous positive serostatus for CMV was 76.9% in recipients, and 53.8% in donors. The conditioning regimen was myeloablative in 57.7% and reduced-intensity in 42.3%. Graf versus host disease (GvHD) prophylaxis was cyclosporine (CsA) plus methotrexate (MTX) in 57.7% and CsA plus mycophenolate mofetil (MMF) in 42.3%. The incidence of acute GvHD was 76.9% and chronic GvHD was 53.8%. Treatment of GVHD was steroids plus CsA or tacrolimus and/or MMF in 76.9% of acute and 46.2% of chronic GvHD. Previously described risk factors for developing CMV infection were compared between patients developing (n=18) and non-developing (n=8) CMV infection. A higher risk for developing CMV infection was associated with previous CMV positive serostatus of the recipient (84% in viremic patients vs. 16% in non-viremic patients; p=0.01) and CsA plus MMF as GvHD prophylaxis (90.9% vs. 9.1%; p=0.04). We analyzed whether having several risk factors for developing CMV infection has an effect on the risk for developing CMV replication after the transplant. Patients that presented four or more risk factors, developed viral replication more frequently than patients having less than four risk factors (91.6% vs. 8.3%; p=0.02). Patients who acquired an earlier specific CMV immune reconstitution did not developed CMV replication, opposite to those with later immune reconstitution (week 2 vs. week 8, p= 0.01). Overall survival at one year was of 44.4% in the group with viral replication, and 100% in the group with no viral replication, p=0.014 (Figure 1). CONCLUSIONS:Patients that did not developed episodes of CMV replication after the transplant presented less than four risk factors for developing CMV infection, developed an early T-cell mediated CMV immune response and had better overall survival. The development of CMV specific immunity able to control CMV replication may be considered as a paradigm of post-transplant immune reconstitution with potential influence on overall survival. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Autologous hematopoietic cell transplantation for multiple sclerosis: a systematic review

Background and objectives: The purpose of this systematic review was to evaluate the safety and efficacy of autologous hematopoietic cell transplantation in patients with progressive multiple sclerosis (MS) refractory to conventional medical treatment. Methods: Eight case series met our a priori inclusion criteria for the primary outcome of progression-free survival. Individual study quality was rated using an 11-item scale for case series. The strength of the overall body of evidence for each outcome was rated using a system developed by the ECRI Institute. Data from different studies were statistically combined using meta-analysis. An additional six studies were included for a summary of mortality and morbidity. Results: For secondary progressive MS, immunoablative therapy with autologous bone marrow/peripheral blood stem cell transplantation was associated with higher progression-free survival (up to 3 years following treatment) when using intermediate-intensity conditioning regimens compared with high-intensity conditioning regimens. The evidence was insufficient to determine whether the treatment was effective in patients with other types of MS. Treatment-related mortality was about 2.7%. Conclusions: Patients with secondary progressive MS refractory to conventional medical treatment have longer progression-free survival following autologous stem cell transplantation with intermediate-intensity conditioning regimens than with high-intensity conditioning regimens.

Reduced Intensity Conditioning with Allogeneic Hematopoietic Cell Transplantation for the Treatment of High-Risk Acute Lymphoblastic Leukemia.

Abstract 1210Poster Board I-232Allogeneic hematopoietic cell transplantation (HCT) with a conventional, high intensity conditioning regimen is an established approach for potentially curing patients (pts) with high-risk acute lymphoblastic leukemia (ALL). However, many pts are not candidates for high intensity conditioning HCT. The use of a reduced intensity conditioning (RIC) for ALL may provide an opportunity to decrease the toxicity of an intense conditioning regimen yet maintain the potential graft vs. leukemia effect. Here we describe the transplantation course and overall survival (OS) of 50 consecutive pts with high-risk ALL that were treated in a multi-center protocol of RIC and allogeneic HCT between February 2000 and August 2008. The median age was 56 (range, 7-69) years. All pts had cytogenetic analysis of bone marrow (BM) at diagnosis. 26 pts had Philadelphia chromosome positive (Ph+) ALL: 18 were in first complete remission (CR1) and 8 were in CR>1 at the time of HCT. 24 pts had Ph–ALL, 12 pts were in CR1 and 12 pts were in CR>1. Pts. were conditioned with fludarabine 90mg/m2 and 2 Gy total body irradiation. Nine pts received peripheral blood stem cells (PBSC) from HLA-identical siblings, 41 pts received grafts from unrelated donors (35 HLA-matched PBSC, 1 BM and 5 received 1-HLA-Ag mismatched PBSC). After the introduction of imatinib mesylate, 19 of the 26 pts with Ph+ALL participated in a study evaluating the safety and efficacy of imatinib starting at day +15 after HCT. Post-grafting immunosuppression consisted of combined mycophenolate mofetil and cyclosporine. Median follow up for surviving pts was 31 months (range, 12-91). One pt had graft rejection (BM recipient). 25 pts (50%) and 4 pts (8%) developed grades 2 and 3-4 acute graft-versus-host disease (GVHD), respectively. Chronic GVHD occurred in 24 pts (53% of pts surviving > 100 days); 15 pts (30%) developed extensive chronic GVHD. 19 pts (38%) relapsed at a median of 4.5 (range, 0.4-59) months. Non relapse mortality (NRM) at 2 and 5 years was 26% and 31%, respectively. Progression-free survival was very similar to OS. For all 50 pts, OS at 2 and 5 years was 37% and 27%, respectively. For pts in CR1 (n=30), OS was 52% and 41%, respectively. In contrast, OS for pts >CR1 (n=20) was significantly lower (13% and 7%, respectively, p=.003). For pts with Ph–ALL, OS was 29%, unchanged at both 2 and 5 years. Those in CR1 had improved OS compared with pts >CR1 (48% vs. 11% unchanged at both 2 and 5 years, respectively, p=0.07, Figure). OS for the 26 pts with Ph+ALL at 2 and 5 years was 45% and 27%, respectively. OS at 2 and 5 years for pts treated with imatinib after HCT was 52% and 43%, respectively, this was superior to the OS for pts with Ph+ALL that did not receive imatinib (p=0.03, Figure). For Ph+ALL pts in CR1 who had no evidence of minimal residual disease (MRD negative, detection by flow cytometry and FISH) prior to HCT and received imatinib (n=12), the OS was 67%, unchanged at both 2 and 5 years. In contrast, the pts with MRD negative Ph+ALL in CR1 who did not receive imatinib (n=4) had OS at 2 and 5 years of 50% and 0%, respectively. Imatinib after HCT was well tolerated: 3 pts required early stopping of imatinib due to associated reversible toxicity. We conclude that RIC with allogeneic HCT is a feasible treatment option that offers durable disease control, particularly for high-risk pts in CR1. The combination of post-transplant imatinib with RIC for Ph+ALL contributed to a substantially improved OS. [Display omitted] Disclosures:Off Label Use: Imatinib - post-grafting treatment. Mycophenolate mofetil - immunosuppression after HCT.

Hematopoietic stem cell transplantation in multiple sclerosis

Intensive immunosuppresion followed by hematopoietic stem cell transplantation (HSCT) has been suggested as potential treatment in severe forms of multiple sclerosis (MS). Since 1995 ca. 400 patients have been treated with HSCT. Stabilization or improvement occurred in almost 70% of cases at least for 3 years post-transplant. Magnetic resonance revealed the capacity of autologous HSCT to suppress or markedly reduce gadolinium-enhancing lesions. The progression of brain atrophy declined after two years post-HSCT. The profound immunological changes following autologous HSCT may result in restoration of self-tolerance. Relatively young patients with active inflammatory lesions of relatively short duration and rapidly progressive disease, but still low disability scores, unresponsive to conventional therapy seem the best candidates for transplantation. Transplant-related mortality was 6% in the first EBMT report and 5.3% in the second one. No deaths were reported since 2001. Very high-intensity conditioning regimen is associated with higher risk of toxicity without significant increase in efficacy. The effects of transplantation and transplantation-related morbidity are dependent on patient-selection, time of transplantation and conditioning regimens used.This review is a comprehensive study of the results obtained in several single-center and multicenter studies. Patient characteristics, transplantations steps, toxicity and clinical outcome have been monitored and compared.

Unmanipulated or CD34 selected haplotype mismatched transplants

Unmanipulated or CD34 selected haplotype mismatched transplantation provides the benefits of hematopoietic stem cell transplant for nearly all patients who do not have a human leukocyte antigen fully matched sibling or who urgently need transplantation. Haplotype mismatched transplant is, however, complicated by delayed immune reconstitution, leading to increased risks of fatal posttransplant opportunistic infections. This review summarizes recent investigations aimed at optimizing outcomes. The graft is a megadose of positively/negatively T-cell-depleted or unmanipulated progenitor cells. Although haploidentical transplant modalities are based mainly on high-intensity conditioning regimens, recently introduced reduced-intensity regimens showed promise in decreasing early transplant-related mortality and in extending the opportunity of hematopoietic stem cell transplantation to an elderly population with more comorbidities. Natural killer cell alloreactivity reduces graft-versus-host disease while augmenting graft-versus-malignancy. Immune reconstitution was highly predictive of outcome following T-cell-depleted transplantation. Mismatched/haploidentical transplant provides an alternative approach for patients with high-risk hematological malignancies or marrow failure syndromes. Overall survival and clinical outcome continue to improve. Future challenges lie in determining the safest preparative conditioning regimen, minimizing graft-versus-host disease while preserving effective graft-versus-malignancy and promoting rapid immune reconstitution.