Sibling Donor Hematopoietic Cell Transplantation Research Articles

New-Onset Post-Transplant Diabetes Mellitus after Allogeneic Hematopoietic Cell Transplant Is Initiated by Insulin Resistance, Not Immunosuppressive Medications.

New-onset post-transplant diabetes mellitus (PTDM) occurs frequently after allogeneic hematopoietic cell transplant (HCT). Although calcineurin inhibitors and corticosteroids are assumed to be the cause for hyperglycemia, patients developing PTDM have elevated fasting C-peptide levels before HCT and before immunosuppressive medications. To determine if PTDM results from established insulin resistance present before transplant, we performed oral glucose tolerance tests (OGTTs) and measured whole body, peripheral, and hepatic insulin sensitivity with euglycemic hyperinsulinemic clamps before and 90 days after HLA-identical sibling donor HCT in 20 patients without pretransplant diabetes. HCT recipients were prospectively followed for the development of new-onset PTDM defined as a weekly fasting blood glucose ≥ 126 mg/dL or random blood glucose ≥ 200 mg/dL. During the first 100 days all patients received calcineurin inhibitors, and 11 individuals (55%) were prospectively diagnosed with new-onset PTDM. PTDM diagnosis preceded corticosteroid treatment. During the pretransplant OGTT, elevated fasting (87 mg/dL versus 101 mg/dL; P = .005) but not 2-hour postprandial glucose levels predicted PTDM diagnosis (P = .648). In response to insulin infusion during the euglycemic hyperinsulinemic clamp, patients developing PTDM had lower whole body glucose utilization (P = .047) and decreased peripheral/skeletal muscle uptake (P = .031) before and after transplant, respectively, when compared with non-PTDM patients. Hepatic insulin sensitivity did not differ. Survival was decreased in PTDM patients (2-year estimate, 55% versus 100%; P = .039). Insulin resistance before HCT is a risk factor for PTDM independent of immunosuppression. Fasting pretransplant glucose levels identified PTDM susceptibility, and peripheral insulin resistance could be targeted for prevention and treatment of PTDM after HCT.

Prediction of absolute risk of acute graft-versus-host disease following hematopoietic cell transplantation.

Allogeneic hematopoietic cell transplantation (HCT) is the treatment of choice for a variety of hematologic malignancies and disorders. Unfortunately, acute graft-versus-host disease (GVHD) is a frequent complication of HCT. While substantial research has identified clinical, genetic and proteomic risk factors for acute GVHD, few studies have sought to develop risk prediction tools that quantify absolute risk. Such tools would be useful for: optimizing donor selection; guiding GVHD prophylaxis, post-transplant treatment and monitoring strategies; and, recruitment of patients into clinical trials. Using data on 9,651 patients who underwent first allogeneic HLA-identical sibling or unrelated donor HCT between 01/1999-12/2011 for treatment of a hematologic malignancy, we developed and evaluated a suite of risk prediction tools for: (i) acute GVHD within 100 days post-transplant and (ii) a composite endpoint of acute GVHD or death within 100 days post-transplant. We considered two sets of inputs: (i) clinical factors that are typically readily-available, included as main effects; and, (ii) main effects combined with a selection of a priori specified two-way interactions. To build the prediction tools we used the super learner, a recently developed ensemble learning statistical framework that combines results from multiple other algorithms/methods to construct a single, optimal prediction tool. Across the final super learner prediction tools, the area-under-the curve (AUC) ranged from 0.613–0.640. Improving the performance of risk prediction tools will likely require extension beyond clinical factors to include biological variables such as genetic and proteomic biomarkers, although the measurement of these factors may currently not be practical in standard clinical settings.

Comparable Outcomes after HLA-Matched Sibling and Alternative Donor Hematopoietic Cell Transplantation for Children with Fanconi Anemia and Severe Aplastic Anemia

Fanconi anemia (FA)-associated severe aplastic anemia (SAA) requires allogeneic hematopoietic cell transplantation (HCT) for cure. With the evolution of conditioning regimens over time, outcomes of alternative donor HCT (AD-HCT) have improved dramatically. We compared outcomes of HLA-matched sibling donor HCT (MSD-HCT; n = 17) and AD-HCT (n = 57) performed for FA-associated SAA at a single institution between 2001 and 2016. Overall survival at 5 years was 94% for MSD-HCT versus 86% for AD-HCT, neutrophil engraftment was 100% versus 95%, platelet recovery was 100% versus 89%, grade II-IV acute graft-versus-host disease (GVHD) was 6% versus 12%, grade III-IV acute GVHD was 6% versus 4%, and chronic GVHD was 0 versus 7%, with no statistically significant differences by type of transplant. The use of UCB was associated with decreased rates of neutrophil recovery in AD-HCT and platelet recovery in both MSD-HCT and AD-HCT. A trend toward a higher serious infection density before day +100 post-HCT was observed in AD-HCT compared with MSD-HCT (P = .02). These data demonstrate that AD-HCT should be considered at the same time as MSD-HCT for patients with FA-associated SAA.

Intravenous Busulfan Compared with Total Body Irradiation Pretransplant Conditioning for Adults with Acute Lymphoblastic Leukemia

Total body irradiation (TBI) has been included in standard conditioning for acute lymphoblastic leukemia (ALL) before hematopoietic cell transplantation (HCT). Non-TBI regimens have incorporated busulfan (Bu) to decrease toxicity. This retrospective study analyzed TBI and Bu on outcomes of ALL patients 18–60 years old, in first or second complete remission (CR), undergoing HLA-compatible sibling, related, or unrelated donor HCT, who reported to the Center for International Blood and Marrow Transplant Research from 2005 to 2014. TBI plus etoposide (25%) or cyclophosphamide (75%) was used in 819 patients, and intravenous Bu plus fludarabine (41%), clofarabine (30%), cyclophosphamide (15%), or melphalan (13%) was used in 299 patients. Bu-containing regimens were analyzed together, since no significant differences for patient outcomes were noted between them. Bu patients were older, with better performance status; took longer to achieve first CR and receive HCT; were treated more recently; and were more likely to receive peripheral blood grafts, antithymocyte globulin, or tyrosine kinase inhibitors. With median follow-up of 3.6 years for Bu and 5.3 years for TBI, adjusted 3-year outcomes showed treatment-related mortality Bu 19% versus TBI 25% (P = .04); relapse Bu 37% versus TBI 28% (P = .007); disease-free survival (DFS) Bu 45% versus TBI 48% (P = .35); and overall survival (OS) Bu 57% versus TBI 53% (P = .35). In multivariate analysis, Bu patients had higher risk of relapse (relative risk, 1.46; 95% confidence interval, 1.15 to 1.85; P = .002) compared with TBI patients. Despite the higher relapse, Bu-containing conditioning led to similar OS and DFS following HCT for ALL.

Influence of Age on Acute and Chronic GVHD in Children Undergoing HLA-Identical Sibling Bone Marrow Transplantation for Acute Leukemia: Implications for Prophylaxis

Relapse remains the major cause of mortality after hematopoietic cell transplantation (HCT) for pediatric acute leukemia. Previous research has suggested that reducing the intensity of calcineurin inhibitor-based graft-versus-host disease (GVHD) prophylaxis may be an effective strategy for abrogating the risk of relapse in pediatric patients undergoing matched sibling donor (MSD) HCT. We reasoned that the benefits of this strategy could be maximized by selectively applying it to those patients least likely to develop GVHD. We conducted a study of risk factors for GVHD, to risk-stratify patients based on age. Patients age <18 years with leukemia who received myeloablative, T cell-replete MSD bone marrow transplantation and calcineurin inhibitor-based GVHD prophylaxis between 2000 and 2013 and were entered into the Center for International Blood and Marrow Transplant Research registry were included. The cumulative incidence of grade II-IV acute GVHD (aGVHD) was 19%, that of grade II-IV aGVHD 7%, and that of chronic GVHD (cGVHD) was 16%. Compared with age 13 to 18 years, age 2 to 12 years was associated with a lower risk of grade II-IV aGVHD (hazard ratio [HR], .42; 95% confidence interval [CI], .26 to .70; P = .0008), grade II-IV aGVHD (HR, .24; 95% CI, .10 to .56; P = .001), and cGVHD (HR, .32; 95% CI, .19 to .54; P < .001). Compared with 2000-2004, the risk of grade II-IV aGVHD was lower in children undergoing transplantation in 2005-2008 (HR, .36; 95% CI, .20 to .65; P = .0007) and in 2009-2013 (HR, .24; 95% CI. .11 to .53; P = .0004). Similarly, the risk of grade III-IV aGVHD was lower in children undergoing transplantation in 2005-2008 (HR, .23; 95% CI, .08 to .65; P = .0056) and 2009-2013 (HR, .16; 95% CI, .04 to .67; P = .0126) compared with those doing so in 2000-2004. We conclude that aGVHD rates have decreased significantly over time, and that children age 2 to 12 years are at very low risk for aGVHD and cGVHD. These results should be validated in an independent analysis, because these patients with high-risk malignancies may be good candidates for trials of reduced GVHD prophylaxis.

Busulfan (Bu) in Combination with Double Nucleoside Analogues Fludarabine (Flu) and Clofarabine (Clo) Plus Vorinostat As a Novel Reduced Toxicity Conditioning Regimen for Allogeneic Hematopoietic Cell Transplantation (HCT) in Patients (pts) with Acute Leukemia

The combination of IV Bu and Flu is an effective and well-tolerated HCT conditioning regimen for patients with advanced acute leukemia. However, relapse remains the main reason for treatment failure. We combined two nucleoside analogues Flu and Clo, and showed cytotoxic synergy when combined with Bu, first in pre-clinical models, and subsequently in a randomized clinical study (Andersson BBMT 2011). We selected the optimized regimen from Andersson et al, and combined with escalating doses of the histone deacetylase inhibitor vorinostat in attempts to augment disease control without increasing toxicity. Herein, we describe our initial experience with this novel regimen for patients with advanced acute leukemia or MDS undergoing allogeneic HCT.Methods: Vorinostat (200mg to 1200mg) was escalated in cohorts of 3 patients, and administered 1 hour prior to the fixed regimen of Flu 10 mg/m2 followed by Clo 40 mg/m2 followed by Bu. The nucleoside analogs were infused over 1 hour once daily for 4 days, followed on each day by Bu, infused over 3 hours to a pharmacokinetically targeted daily area under the curve (AUC) of 5500 μMol-min ± 5%. Dilantin was given for seizure prophylaxis. GVHD prophylaxis was based on tacrolimus andmini-MTX, with the addition of rabbit anti-thymocyte globulin (4 mg/kg total dose) for unrelated donor transplants. The presence of minimal residual disease (MRD) was determined by multiparameter flow cytometry.Results: 21 patients (7 AML, 14 ALL) with median age 43 years (range 19-60) received an allogeneic matched sibling (n=10) or unrelated donor (n=11) HCT in CR1 (n=13), CR2 (n=1), primary induction failure (n=5), or relapse (n=2). Twelve patients had MRD or overt disease present at time of HCT. Ten patients had high-risk karyotype defined by t(9;22) (n=3), t(4;11) (n=2), complex (n=2), or del 5 or 7 (n=3). Median time from diagnosis to HCT was 5 months (range 3-48). Median time to ANC > 0.5 x 109/L and platelets > 20 x 109/L were 11 (range 10-15) and 12 days (5-30), respectively. Excluding grade 1 toxicities, the most commonly reported toxicities were nausea with maximum grade 2 (71%), followed by grade 2 or 3 mucositis (64%). Grade 2 or 3 reversible elevation of liver function tests was noted in 54% of pts, including 1 case of reversible VOD. No renal toxicities were noted. Two patients with prior systemic treatment for acute GVHD died of infections (disseminated adenovirus and E.coli sepsis). Ten patients achieved CR and clearance of MRD by day +30 after HCT; one patient had progressive disease and on patient died before disease restaging. Eighteen patients achieved 100% donor chimerism at 30 days following HCT, 2 patients remain with mixed chimerism by 100 day assessment following HCT, and 1 patient died before assessment. The incidence of grades II-IV acute GVHD is 43% and chronic extensive GVHD among 18 evaluable patients is 24%. With a median follow-up of 10 months among surviving patients (1-22), overall and progression-free survival at 6 months is 95% and 71%, respectively. Early results suggest excellent disease control in MRD negative patients (Figure).Conclusion: The Vorinostat-Flu-Clo-Bu combination is well-tolerated and did not add appreciable toxicity in these patients with high-risk leukemia. Longer follow-up is needed to better assess disease control. [Display omitted] DisclosuresCiurea:Spectrum Pharmaceuticals: Other: Advisory Board; Cyto-Sen Therapeutics: Equity Ownership. Patel:Ziopharm Oncology: Equity Ownership, Patents & Royalties; Intrexon: Equity Ownership, Patents & Royalties.

Haploidentical and Matched Sibling Donor Hematopoietic Cell Transplantation for Patients with HLA-Homozygous Haplotypes

More than 1% of the Japanese population has HLA-homozygous haplotypes. For patients with such haplotypes, HLA-haploidentical family members who have no HLA mismatch in the graft-versus-host direction are readily available donor candidates for hematopoietic cell transplantation (HCT). In this study, the outcomes of patients with homozygous HLA-A, -B, and -DRB1 antigens who received HCT without T cell depletion from a haploidentical related donor with mismatches in the host-versus-graft direction only (hetero-to-homo, n = 78) or from an HLA-matched sibling donor (MSD) (MSD-homo, n = 153) were compared with those in patients with heterozygous haplotypes who received HCT from an MSD (MSD-hetero, n = 7242). Transplant outcomes in the hetero-to-homo group were similar to those in the MSD-hetero group regarding neutrophil engraftment, grades III to IV acute graft-versus-host disease (aGVHD), nonrelapse mortality (NRM), relapse, and overall survival. On the other hand, the incidences of severe aGVHD and NRM in the MSD-homo group were significantly lower than those in the MSD-hetero group (grades III to IV aGVHD: aHR .50, P = .034; NRM: aHR .48, P = .004). In conclusion, patients with HLA-homozygous haplotypes achieved lower GVHD and NRM rates for MSD transplantation than those with HLA-heterozygous haplotypes. When an MSD or an appropriate alternative donor is not available for patients with HLA-homozygous haplotypes who need immediate transplantation, transplantation from a haploidentical donor without T cell depletion is a viable option, given the comparable transplant outcomes for hetero-to-homo HCT and MSD-hetero HCT.

A Single Institution Study of Allogeneic Hematopoietic Stem Cell Transplant for MDS and AML in Patients 60 Years of Age and Older: Impact of Disease Risk Index and Secondary Disease

Background: Allogeneic Hematopoietic cell transplantation (HCT) is potentially curative therapy for MDS and AML. Although the median age at presentation is >65 years, most patients receiving HCT for these disorders are young (<60years). With the availability of Reduced Intensity Conditioning (RIC) many older patients are able to undergo HCT. The older age group is the most rapidly increasing cohort in CIBMTR registry. We analyzed the outcomes of AML and MDS patients' ≥ 60 years who received allogeneic sibling or unrelated donor HCT at our institution between 2009 and 2014. We also evaluated the influence of patient-, disease-, and transplant related factors on outcomes.Methods: Prospectively collected data available in the BMT databases at Mayo Clinic Florida, Arizona and Rochester as well as individual patient charts were reviewed after IRB approval. Patients with MDS or AML in complete remission at the time of transplant were included; those with active disease, induction failure, or prior transplant were excluded. HCT-specific comorbidity index (HCT-CI) and the disease risk index (DRI- Armand et al. Blood 2012) was noted. Survival estimates were calculated using the Kaplan Meier method. Associations with survival were explored using single variable Cox-regression modeling and log-rank tests.Results: 80 patients were included; 68 AML and 12 MDS. 31 (39%) were male. Median age 66 years (range 60-75). 33%, 52%, and 13% patients had ECOG status of 0, 1, >2, respectively. Thirty-seven patients (46%) had low or intermediate DRI and 43(54%) had high DRI. Twenty-two (28%), 24 (30%), and 34 (43%) patients had HCT-CI of 0, 1, or >2. There were equal number of sibling and unrelated donors; 85% were full HLA match and 15% with 1 or 2 mismatches; mean age of the donors was 52years (range18-74). Transplant conditioning was fludarabine-containing reduced intensity regimens in 78 (97%), 2 patients received myeloablative conditioning. The source of stem cells was peripheral blood in all patients. A median of 5.87 x10^6 CD34/kg donor cells were infused (range 1.58-10.92 X10^6). All patients received calcineurin inhibitor based GVHD prophylaxis (tacrolimus 56%, cyclosporine 44%); 6 patients also received ATG.The median follow up of survivors was 13 months. Kaplan Meier estimate of overall survival at 100 days, 1 year, and 2 years was 90%, 64%, and 55%. Cumulative incidence of relapse at 6 months, 1 year, and 2 years was 19.5%, 22.3%, and 27.1%. Relapse free survival at 2 years was 50%. The non-relapse/ treatment related mortality at 6 months, 1 year and 2 years was 11.7%, 15.9% and 15.9%. The rate of acute grade 2-4 GVHD was 30% and chronic GVHD was 39%. Univariate analysis identified secondary disease (compared to de novo) and high DRI(compared to low/intermediate) to be associated with worse mortality - HR 2.54 (1.31-4.93; P = 0.006), and 2.31 (1.13-4.73; P = 0.021), respectively. Probability of overall survival at 6 months, 1 year, and 2 years for patients with de novo disease (n=57) vs. secondary disease (n=23) was 87.1% vs. 64.5%, 71.1 vs. 45.6%, and 63.2 vs. 32.6%, respectively; P= 0.006. There was no effect of donor age, donor type or degree of mis-match on the survival.Conclusion: Allogeneic HCT is feasible in older patients with MDS and AML utilizing reduced intensity conditioning regimens with acceptable outcomes that are comparable to published results in younger patients. Patients with high DRI and secondary disease have poorer overall survival as compared to those with de novo disease and low/intermediate disease risk index. These data support other studies that age alone does not negatively influence transplant outcomes. DisclosuresNo relevant conflicts of interest to declare.

FLT3 Mutation Increases Relapse Risk after Allogeneic Hematopoietic Cell Transplant for Acute Myeloid Leukemia in First or Second Complete Remission: A Center for International Blood and Marrow Transplant Research (CIBMTR) Analysis

Relapse after allogeneic hematopoietic cell transplant (HCT) remains a major cause of transplant failure. Patients (pts) with FLT3 mutated acute myeloid leukemia (AML) tend to have poor prognosis and are often referred for early HCT. We studied 511 patients to determine if FLT3 mutations impact transplant outcomes.Adults with a diagnosis of de-novo AML, with available FLT3 mutation status in first or second complete remission (CR) who underwent a human leukocyte antigen (HLA) matched sibling or unrelated donor (8/8 or 7/8) HCT after myeloablative (MAC), non-myeloablative (NMA), or reduced intensity conditioning (RIC) reported to the CIBMTR from 2008-2011 were included. Clinical outcomes following HCT for FLT3 positive and FLT3 negative AML pts were compared adjusting for significant patient-, disease-, and HCT-related variables.511 pts met the inclusion criteria: 158 (31%) with FLT3 mutations. Median follow-up of survivors was 37 months (range, 12-65). Patient characteristics are shown in Table 1. The FLT3 mutated group had significantly higher white blood cell (WBC) count at diagnosis, more pts. with normal cytogenetics and more cycles of pre-HCT consolidation. Univariate analysis (Table 2) showed increased probability of relapse after HCT (log-rank p=0.01) in the FLT3 positive group but no significant differences in overall survival (OS) (log-rank p=0.13). There were no statistical differences in non-relapse mortality (NRM), relapse-free survival (RFS), or the cumulative incidence of acute and chronic GVHD. In multivariate analysis performed excluding the confounder “WBC count at diagnosis” FLT3 mutation status had a statistically significant negative effect on risk of relapse (P ≤ 0.05), but no effect on overall mortality.We could not address the differential impact of varying FLT3 mutations or interaction of other molecular aberrations with FLT3, in addition we did not have information about post relapse interventions. Encouragingly, nearly 50% of patients with FLT3 positive AML who underwent allogeneic HCT in CR were long-term survivors after allogeneic HCT. Though associated with augmented risks of relapse, FLT3 mutation status does not adversely impact long-term survival. Pre-emptive strategies using FLT3 inhibitors after HCT may reduce relapse risk and should be studied prospectively in order to improve outcomes of these high-risk patients.Table 1:Patient CharacteristicsFLT3 Negative (N=353)FLT3 Positive (N=158)Median Age (Range)46 yrs (18-60)47 yrs(18-60)Median WBC count * x109/L (Range)10 (<1-344)34 (<1-305)Cytogenetics*Normal114 (32%)102 (65%)Other228 (65%)51 (32%)Missing11 (3%)5 (3%)Disease StatusCR1252 (71%)125 (79%)CR2101 (29%)33 (21%)Cycles of consolidations prior to HCT in CR1*086 (34%)24 (19%)171 (28%)49 (39%)≥255 (26%)40 (32%)Missing30 (12%)12 (10%)Donor Type8/8 Sibling150 (42%)67 (42%)8/8 Unrelated165 (47%)70 (44%)7/8 Unrelated38 (11%)21 (13%)Conditioning RegimenMAC302 (86%)136 (87%)NMA/RIC51 (14%)21 (13%)* p ≤ 0.05Table 2:Univariate Analysis of Outcomes at 3 yearsFLT3 Negative (N=353)FLT3 Positive (N=158)Relapse * (95% CI)28% (24-33)38% (30-45)Overall Survival (95% CI)55% (50-60)49% (40-57)* p ≤ 0.05 [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Low CD34 Dose Is Associated with Poor Survival after Reduced-Intensity Conditioning Allogeneic Transplantation for Acute Myeloid Leukemia and Myelodysplastic Syndrome

Reduced-intensity conditioning/nonmyeloablative conditioning regimens are increasingly used in allogeneic hematopoietic cell transplantation (HCT). Reports have shown CD34+ dose to be important for transplantation outcome using myeloablative conditioning. The role of CD34+ dose of peripheral blood progenitor cells (PBPC) has not been previously analyzed in a large population undergoing reduced-intensity conditioning/nonmyeloablative HCT. We studied 1054 patients, ages 45 to 75 years, with acute myeloid leukemia or myelodysplastic syndrome who underwent transplantation between 2002 and 2011. Results of multivariate analysis showed that PBPC from HLA-matched siblings containing <4 × 106 CD34+/kg was associated with higher nonrelapse mortality (hazard ratio [HR], 2.03; P = .001), overall mortality (HR, 1.48; P = .008), and lower neutrophil (odds ratio [OR], .76; P = .03) and platelet (OR, .76; P = .03) recovery. PBPC from unrelated donors with CD34+ dose < 6 × 106 CD34+/kg was also associated with higher nonrelapse (HR, 1.38; P = .02) and overall mortality (HR, 1.20; P = .05). In contrast to reports after myeloablative HCT, CD34+ dose did not affect relapse or graft-versus-host disease with either donor type. An upper cell dose limit was not associated with adverse outcomes. These data suggest that PBPC CD34+ doses >4 × 106 CD34+/kg and >6 × 106 CD34+/kg are optimal for HLA-matched sibling and unrelated donor HCT, respectively.

Outcomes of Human Leukocyte Antigen–Matched Sibling Donor Hematopoietic Cell Transplantation in Chronic Lymphocytic Leukemia: Myeloablative Versus Reduced-Intensity Conditioning Regimens

Allogeneic hematopoietic cell transplantation (HCT) can cure some chronic lymphocytic leukemia (CLL) subjects. This study compared outcomes of myeloablative (MA) and reduced-intensity conditioning (RIC) transplants from HLA-matched sibling donors (MSD) for CLL. From 1995 to 2007, information regarding 297 CLL subjects was reported to the Center of International Blood and Marrow Transplant Research; of these, 163 underwent MA and 134 underwent RIC MSD HCT. The MA subjects underwent transplantation less often after 2000 and less commonly received antithymocyte globulin (4% versus 13%, P = .004) or prior antibody therapy (14% versus 53%; P < .001). RIC was associated with a greater likelihood of platelet recovery and less grade 2 to 4 acute graft-versus-host disease compared with MA conditioning. One- and 5-year treatment-related mortality (TRM) were 24% (95% confidence intervals [CI], 16% to 33%) versus 37% (95% CI, 30% to 45%; P = .023), and 40% (95% CI, 29% to 51%) versus 54% (95% CI, 46% to 62%; P = .036), respectively, and the relapse/progression rates at 1 and 5 years were 21% (95% CI, 14% to 29%) versus 10% (95% CI, 6% to 15%; P = .020), and 35% (95% CI, 26% to 46%) versus 17% (95% CI, 12% to 24%; P = .003), respectively. MA conditioning was associated with better progression-free (PFS) (relative risk, .60; 95% CI, .37 to .97; P = .038) and 3-year survival in transplantations before 2001, but for subsequent years, RIC was associated with better PFS and survival (relative risk, 1.49 [95% CI, .92 to 2.42]; P = .10; and relative risk, 1.86 [95% CI, 1.11 to 3.13]; P = .019). Pretransplantation disease status was the most important predictor of relapse (P = .003) and PFS (P = .0007) for both forms of transplantation conditioning. MA and RIC MSD transplantations are effective for CLL. Future strategies to decrease TRM and reduce relapses are warranted.

Older Age, Use Of Myeloablative Regimens For Malignant Diseases and Chronic Graft-Versus-Host Disease Are Risk Factors For Avascular Necrosis Of Bone After Allogeneic Hematopoietic Cell Transplantation In Children and Adolescents

▪Avascular necrosis (AVN) of the bone is a painful and debilitating complication of allogeneic hematopoietic cell transplantation (HCT) that is associated with significant morbidity and often requires surgery. Risk factors for its development in pediatric allogeneic HCT recipients are not well described. To assess risk factors for AVN in children and adolescents following allogeneic HCT, we conducted a nested case-control study with a matched cohort of 638 patients reported to the Center of International Blood and Marrow Transplant Research who were ≤ 21 years of age, received their first allogeneic transplant between 1990 to 2008 in the United States and had survived ≥ 6 months from HCT. Overall, 160 cases with AVN were identified. Each case was matched with up to 3 controls by same year of HCT, similar length of follow-up and by transplant center (478 controls). Cases and controls were confirmed via central review of radiology, pathology and/or surgical procedure reports. The median age for cases was 15 (range 2-21) years, 49% were male, 65% had acute leukemia, 65% had received high-dose total body irradiation (TBI) based conditioning regimen, and 65% had received unrelated donor HCT. Among cases, 18% had a history of acute graft-versus-host disease (GVHD) while 56% had a history of chronic GVHD prior to development of AVN. Median time from HCT to diagnosis of AVN was 14 (range <1-172) months. We evaluated age, gender, diagnosis, conditioning regimen, TBI, donor source and GVHD as risk factors for AVN. On conditional logistic regression, increasing age at HCT, female gender and chronic GVHD were significantly associated with increased risks of AVN. Compared to patients receiving myeloablative regimens for malignant diseases, lower risks of AVN were seen in patients with non-malignant diseases and those who had received reduced intensity conditioning regimen for malignant diseases. (Table). Patients receiving unrelated donor transplant had lower risks of AVN compared to HLA-identical sibling donor HCT recipients; there was no significant interaction between donor source and GVHD status. Lack of data on pre- and post-HCT steroid exposure was a limitation of our study. Our findings suggest that children at high risk for AVN include those within the age group where rapid bone growth occurs as well as those who experience exposure to high-dose myeloablative conditioning regimens and immunosuppression post-HCT for the treatment of GVHD. Our study identifies important risk factors for AVN in a large cohort of pediatric HCT recipients. Future studies should evaluate the role of surveillance and preventive strategies for AVN in pediatric HCT recipients who are at high risk for development of AVN. Disclosures:No relevant conflicts of interest to declare.

Long-term follow-up of a prospective randomized trial comparing CYA and MTX with CYA and mycophenolate mofetil for GVHD prophylaxis in myeloablative sibling donor hematopoietic cell transplantation

Long-term follow-up of a prospective randomized trial comparing CYA and MTX with CYA and mycophenolate mofetil for GVHD prophylaxis in myeloablative sibling donor hematopoietic cell transplantation

Phase 2 clinical trial of rapamycin-resistant donor CD4+ Th2/Th1 (T-Rapa) cells after low-intensity allogeneic hematopoietic cell transplantation

AbstractIn experimental models, ex vivo induced T-cell rapamycin resistance occurred independent of T helper 1 (Th1)/T helper 2 (Th2) differentiation and yielded allogeneic CD4+ T cells of increased in vivo efficacy that facilitated engraftment and permitted graft-versus-tumor effects while minimizing graft-versus-host disease (GVHD). To translate these findings, we performed a phase 2 multicenter clinical trial of rapamycin-resistant donor CD4+ Th2/Th1 (T-Rapa) cells after allogeneic-matched sibling donor hematopoietic cell transplantation (HCT) for therapy of refractory hematologic malignancy. T-Rapa cell products, which expressed a balanced Th2/Th1 phenotype, were administered as a preemptive donor lymphocyte infusion at day 14 post-HCT. After T-Rapa cell infusion, mixed donor/host chimerism rapidly converted, and there was preferential immune reconstitution with donor CD4+ Th2 and Th1 cells relative to regulatory T cells and CD8+ T cells. The cumulative incidence probability of acute GVHD was 20% and 40% at days 100 and 180 post-HCT, respectively. There was no transplant-related mortality. Eighteen of 40 patients (45%) remain in sustained complete remission (range of follow-up: 42-84 months). These results demonstrate the safety of this low-intensity transplant approach and the feasibility of subsequent randomized studies to compare T-Rapa cell-based therapy with standard transplantation regimens. This trial was registered at www.cancer.gov/clinicaltrials as #NCT 00077480.

Late Effects in Hematopoietic Cell Transplant Recipients with Acquired Severe Aplastic Anemia: A Report from the Late Effects Working Committee of the Center for International Blood and Marrow Transplant Research

With improvements in hematopoietic cell transplant (HCT) outcomes for severe aplastic anemia (SAA), there is a growing population of SAA survivors after HCT. However, there is a paucity of information regarding late effects that occur after HCT in SAA survivors. This study describes the malignant and nonmalignant late effects in survivors with SAA after HCT. A descriptive analysis was conducted of 1718 patients post-HCT for acquired SAA between 1995 and 2006 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). The prevalence and cumulative incidence estimates of late effects are reported for 1-year HCT survivors with SAA. Of the HCT recipients, 1176 (68.5%) and 542 (31.5%) patients underwent a matched sibling donor (MSD) or unrelated donor (URD) HCT, respectively. The median age at the time of HCT was 20 years. The median interval from diagnosis to transplantation was 3 months for MSD HCT and 14 months for URD HCT. The median follow-up was 70 months and 67 months for MSD and URD HCT survivors, respectively. Overall survival at 1 year, 2 years, and 5 years for the entire cohort was 76% (95% confidence interval [CI]: 74-78), 73% (95% CI: 71-75), and 70% (95% CI: 68-72). Among 1-year survivors of MSD HCT, 6% had 1 late effect and 1% had multiple late effects. For 1-year survivors of URD HCT, 13% had 1 late effect and 2% had multiple late effects. Among survivors of MSD HCT, the cumulative incidence estimates of developing late effects were all <3% and did not increase over time. In contrast, for recipients of URD HCT, the cumulative incidence of developing several late effects exceeded 3% by 5 years: gonadal dysfunction 10.5% (95% CI: 7.3-14.3), growth disturbance 7.2% (95% CI: 4.4-10.7), avascular necrosis 6.3% (95% CI: 3.6-9.7), hypothyroidism 5.5% (95% CI: 2.8-9.0), and cataracts 5.1% (95% CI: 2.9-8.0). Our results indicated that all patients undergoing HCT for SAA remain at risk for late effects, must be counseled about, and should be monitored for late effects for the remainder of their lives.

HLA DR15 Antigen Status Does Not Impact Graft-versus-Host Disease or Survival in HLA-Matched Sibling Transplantation for Hematologic Malignancies

The HLA class II DRB1 antigen DR15 is an important prognostic marker in immune-mediated marrow failure states. DR15 has also been associated with favorable outcomes (reduced acute graft-versus-host disease [aGVHD] and relapse) after allogeneic hematopoietic cell transplant. To elucidate the impact of DR15 on transplantation outcomes, we conducted a retrospective study of 2891 recipients of first allogeneic stem cell transplant from HLA-matched sibling donors for the treatment of acute leukemia, chronic myeloid leukemia, or myelodysplastic syndrome (MDS) between 1990 and 2007. All patients received conventional myeloablative conditioning, T-replete grafts, and cyclosporine plus methotrexate-based GVHD prophylaxis. DNA-based HLA typing allowed categorization of 732 patients (25.3%) as positive and 2159 patients (74.7%) as negative for DRB1*15:01 or *15:02 (DR15). There were no significant differences in baseline characteristics between the HLA DR15 positive and negative groups. In univariate analysis, HLA-DR15 status had no impact on neutrophil engraftment, aGVHD, chronic GVHD (cGVHD), treatment-related mortality, relapse, disease-free survival, or overall survival (OS). In multivariate analysis, DR15 status showed no significant difference in aGVHD, cGVHD, OS, or relapse. In conclusion, DR15 status had no impact on major HLA-matched sibling donor hematopoietic cell transplant outcomes in this large and homogenous cohort of patients with leukemia and MDS.

HLA DR15 Antigen Status Does Not Impact Graft-Versus-Host Disease or Disease-Free Survival in HLA-Matched Sibling Transplantation for Hematologic Malignancies

Abstract 3094The HLA class II DRB1 antigen DR15 is an important immunobiologic marker in immune mediated marrow failure states. DR15 has also been reported in small studies to be associated with favorable outcomes (reduction in acute GVHD and reduced relapse resulting in improved overall survival) after allogeneic hematopoietic cell transplant. To elucidate the impact of DR15 on major transplant outcomes, we conducted a retrospective study of 2, 891 recipients of first marrow or mobilized peripheral blood stem cell transplantation for the treatment of acute myeloid leukemia (n=1038), acute lymphoblastic leukemia (n=700), chronic myeloid leukemia (n=948), or myelodysplastic syndrome (n=205) between 1990–2008 and reported to the CIBMTR registry. Selection was confined to HLA-identical sibling transplantation to avoid HLA-disparity as a driving force for observed differences. All patients received conventional myeloablative conditioning, T-replete grafts and cyclosporine plus methotrexate- based GVHD prophylaxis. DNA-based HLA typing allowed categorization of 732 (25.3%) patients as positive and 2159 (74.7%) patients as negative for DRB1*15 :01 or *15 :02 (DR15). There were no significant differences in baseline characteristics between the HLA DR15-positive and -negative groups. In univariate analysis, HLA-DR15 status had no impact on neutrophil engraftment, acute graft-versus-host disease (GvHD) II-IV or III-IV, chronic GVHD, treatment related mortality, relapse, disease-free survival or overall survival. Confining the univariate analysis to myeloid malignancies did not alter these findings. Multivariate analysis models were constructed with DR15 status forced into the models in all steps of model building and the final model regardless of its statistical significance. Other variables tested included: donor/recipient age, CMV status, disease, disease stage, graft source, Karnofsky score, race and year of transplant. Variables that attained a p-value ≤0.05 were held in the final multivariate models. In multivariate analysis, DR15 status showed no significant difference in the primary outcomes of acute GVHD II-IV or III-IV, chronic GVHD, overall survival, or relapse. In conclusion, DR15 status had no impact on major HLA-matched sibling donor hematopoietic cell transplantation outcomes in this large and homogenous cohort of leukemia and MDS patients. Disclosures:No relevant conflicts of interest to declare.

Outcomes of Allogeneic Hematopoietic Cell Transplantation for Adolescent and Young Adults Compared with Children and Older Adults with Acute Myeloid Leukemia

Adolescents and young adults (AYAs) with cancer have not experienced improvements in survival to the same extent as children and older adults. We compared outcomes among children (<15 years), AYAs (15-40 years) and older adults (>40 years) receiving allogeneic hematopoietic cell transplant (HCT) for acute myeloid leukemia (AML). Our cohort consisted of 900 children, 2,708 AYA, and 2,728 older adult recipients of HLA-identical sibling or unrelated donor (URD) transplantation using myeloablative or reduced-intensity/nonmyeloablative conditioning. Outcomes were assessed over three time periods (1980-1988, 1989-1997, 1998-2005) for siblings and two time periods (1989-1997, 1998-2005) for URD HCT. Analyses were stratified by donor type. Results showed overall survival for AYAs using either siblings or URD improved over time. Although children had better and older adults had worse survival compared with AYAs, improvements in survival for AYAs did not lag behind those for children and older adults. After sibling donor HCT, 5-year adjusted survival for the three time periods was 40%, 48%, and 53% for children, 35%, 41%, and 42% for AYAs, and 22%, 30%, and 34% for older adults. Among URD HCT recipients, 5-year adjusted survival for the twotime periods was 38% and 37% for children, 24% and 28% for AYAs, and 19% and 23% for older adults. Improvements in survival occurred because of a reduction in risk of treatment-related mortality. The risk of relapse did not change over time. Improvements in survival among AYAs undergoing allogeneic HCT for AML have paralleled those among children and older adults.

Chimerism Analysis Is Predictive of Relapse-Free Survival After Allogeneic Transplantation for MDS

AbstractAbstract 1332Chimerism analysis permits evaluation of the extent of donor engraftment following allogeneic hematopoietic cell transplantation (HCT) via differentiation between donor- and recipient-derived cells. Though relapse remains a major cause of treatment failure post-HCT for hematologic malignancies, the clinical utility of chimerism analysis for the early detection of morphologic relapse varies between different diseases and remains controversial. The predictive value of chimerism analysis for relapse rates and mortality in myelodysplastic syndromes (MDS) is not well-described. We reviewed serial chimerism results for 72 consecutive patients (pts) who underwent allogeneic HCT for MDS between 1999 and 2009; 9 pts were excluded from analysis due to lack of appropriately timed chimerism studies. Donor engraftment was initially assessed 28 days post-HCT and then at 2-week intervals through day 100. Chimerism studies were performed with peripheral blood using a short tandem repeat assay by PCR-based analysis. Acute and chronic GVHD rate, relapse-free survival (RFS), and overall survival (OS) were assessed for patients with donor leukocyte chimerism and T-cell chimerism ≥95% and <95%. The median age was 51 years (range 20–70) and 52% were male. The median time from MDS diagnosis to HCT was 5.4 months; 9 pts (14%) were in complete remission at the time of HCT, 11 (18%) were in partial remission, 17 (27%) had relapsed or refractory disease, and 26 (41%) were untreated. HCT-comorbidity index was low in 25 pts (40%), intermediate in 18 (29%), and high in 20 (32%). 31 pts (49%) received sibling donor HCT and the remainder received an unrelated donor graft. 40 (63%) received bone marrow and 23 (37%) received peripheral stem cells. Myeloablative (MA) busulfan- or cyclophosphamide-based preparative regimens were used in 47 pts (75%) and a non-myeloablative (NMA) regimen with fludarabine and TBI was given to the remaining pts. 61 pts achieved ≥95% donor leukocyte chimerism at a median of 29 days and 39 evaluable pts achieved ≥95% donor T-cell chimerism at a median of 42 days. Two pts did not achieve donor leukocyte chimerism ≥95% and 9 did not achieve donor T-cell chimerism ≥95% at any timepoint. Univariable analysis of prognostic factors for relapse showed that donor leukocyte chimerism ≥95% was significantly associated with lower probability of relapse (hazard ratio [HR] 0.11, 95% confidence interval [CI] 0.02–0.51, p=.005), whereas prior exposure to radiation therapy (excluding exposure during HCT preparative regimen) was associated with increased probability of relapse (HR 3.48, 95% CI 1.14–10.60, p=.028). Multivariable analysis implicated donor leukocyte chimerism <95% as the only independent risk factor for relapse. Transplant type (MA vs NMA) and cell source did not significantly impact the likelihood of relapse. Donor leukocyte chimerism ≥95% was not associated with acute or chronic GVHD. Univariable analysis of risk factors for survival showed that donor leukocyte chimerism ≥95% was associated with improved RFS (HR 0.29, 95% CI 0.09–0.97, p=.045) but not OS, both findings of which were confirmed on multivariable analysis. Donor T-cell chimerism ≥95% was not significant in univariable analysis; however, in multivariable analysis, controlling for comorbidity scores, donor T-cell chimerism <95% was associated with lower risk of chronic GVHD (HR 0.18, 95% CI 0.04–0.88, p=.034) but did not significantly impact relapse, RFS, or OS. In conclusion, achievement of a high donor leukocyte chimerism post-HCT for MDS is associated with improved RFS. Donor T-cell chimerism, however, is not predictive of outcome and its routine use for MDS pts should be reevaluated. Pts with donor leukocyte chimerism <95% might be considered for immunologic interventions such as withdrawal of immunosuppression or donor lymphocyte infusion. Disclosures:No relevant conflicts of interest to declare.

Success With A Shorter Course Preemptive Treatment For Cytomegalovirus (CMV) Reactivation After Myeloablative Hla Matched Sibling Donor Hematopoietic Cell Transplantation (HCT)

Success With A Shorter Course Preemptive Treatment For Cytomegalovirus (CMV) Reactivation After Myeloablative Hla Matched Sibling Donor Hematopoietic Cell Transplantation (HCT)