HLA-matched Sibling Bone Marrow Research Articles

332 - Familial Haploidentical (FHI) T-Cell Depleted (TCD) with T-Cell Addback Stem Cell Transplantation for Patients with High-Risk Sickle Cell Disease (SCD) (IND 14359)

Allogeneic stem cell transplantation (AlloSCT) from HLA-matched unaffected sibling donors (MSD) has been successful for high-risk SCD, and is the only known curative therapy (Freed/Cairo et al, BMT, 2012). We have recently demonstrated 100% event free survival and absence of sickle cell symptoms following reduced toxicity conditioning and HLA matched sibling bone marrow or cord blood AlloSCT (Bhatia/Cairo et al, BMT, 2014). However, 5 out of 6 children who might benefit from this therapy lack an HLA matched family donor. Identifiable matched unrelated adult donors (URD) in this ethnic group are extremely limited and results from unrelated cord blood transplants are poor (Radhakrishnan K/Cairo et al., BBMT 2013, Kamani et al., BBMT, 2012). We previously demonstrated the use of positive CD34 selection followed by T cell add back (2 x 105 CD3/kg) from unrelated donors in pediatric recipients with both malignant and nonmalignant disease lead to 100% engraftment with minimal acute GVHD (aGVHD). In a high-risk FHI TCD thalassemia study, 16/22 cases engrafted without aGVHD and with 90% overall survival (Sodani et al., Blood, 2010). FHI TCD AlloSCT could expand the donor pool and improve outcomes for patients with high risk SCD. This SCD consortium trial is investigating the safety, feasibility, EFS, donor chimerism, graft failure, aGVHD and chronic GVHD (cGVHD), and infectious mortality after FHI TCD AlloSCT in high-risk SCD patients ([Figure 1][1]). High risk features included one or more of the following: ≥1 CVA, ≥2 ACS, ≥3 VOC in past 2 years, or 2 abnormal TCDs. Patients (2-20.99 yrs) without an 8/8 HLA MSD or URD and who have ≥1 high-risk SCD features were eligible. Patients received hydroxyurea 60 mg/kg/d and azathioprine 3mg/kg/d, day -59 – day -11, fludarabine (30mg/m2/d x5d), busulfan (3.2 mg/kg/d x4d [<4yrs of age: 4 mg/kg/d x4d]), thiotepa (10 mg/kg/d x1d), cyclophosphamide (50mg/kg/d x4d), R-ATG (2mg/kg/d x4d), and TLI (500cGy) followed by FHI T-cell depleted AlloSCT. AGVHD prophylaxis included tacrolimus single agent. We utilized the CliniMACS (IND 14359) to enrich for peripheral blood hematopoietic progenitor cells (HPC's); target dose of 10 x 106 CD34+ cells/kg with 2 x 105 CD3+ T cells/kg added back as a final CD3/kg concentration. Six patients have received AlloSCT to date ([Figure 2][2]). All patients utilized maternal donors who encountered no complications during collection. All had early neutrophil engraftment (median day +9), ≥98% whole blood chimerism and ≥85% RBC donor chimerism, no aGVHD or cGVHD ([Figure 2][2]). One patient developed late hepatic SOS and died at day +59; the remainder are alive and free of disease (day +12 to +642). One more patient has been enrolled and has begun conditioning and others are in the early part of their transplant process. Early results indicate FHI TCD AlloSCT is feasible in high-risk SCD patients who lack a MSD or URD. A larger cohort with longer term follow-up is needed to assess long-term safety and outcomes (Supported by FDA 5R01FD004090 and a grant from Otsuka) (IND #14359 and NCT 01461837). http://www.sicklecelltransplantconsortium.org ![Figure 1][3] Figure 1 ![Figure 2][3] Figure 2 Disclosures No relevant conflicts of interest to declare. [1]: #F1 [2]: #F2 [3]: pending:yes

Comparison of graft-versus-host disease-free, relapse-free survival according to a variety of graft sources: antithymocyte globulin and single cord blood provide favorable outcomes in some subgroups.

Graft-versus-host disease-free relapse-free survival, which is defined as the absence of grade III-IV acute graft-versus-host disease, systemically treated chronic graft-versus-host disease, relapse, and death, is a novel, meaningful composite end point for clinical trials. To characterize risk factors and differences in graft-versus-host disease-free relapse-free survival according to a variety of graft sources, we analyzed 23,302 patients with hematologic malignancy that had a first allogeneic transplantation from 2000 through 2013 using the Japanese national transplant registry database. The 1-year graft-versus-host disease-free relapse-free survival rate was 41% in all patients. The rate was higher after bone marrow transplantation than after peripheral blood stem cell transplantation due to the lower risks of III-IV acute and chronic graft-versus-host disease. The rate was highest after HLA-matched sibling bone marrow transplantation. The rate after single cord blood transplantation was comparable to that after HLA-matched unrelated bone marrow transplantation among patients aged 20 years or under, and was comparable or better than other alternative graft sources among patients aged 21 years or over, due to the low risk of chronic graft-versus-host disease. Other factors associated with better graft-versus-host disease-free relapse-free survival include female patients, antithymocyte globulin prophylaxis (for standard-risk disease), recent years of transplantation, sex combinations other than from a female donor to a male patient, the absence of prior autologous transplantation, myeloablative conditioning, negative cytomegalovirus serostatus, and tacrolimus-based prophylaxis. These results provide important information to guide the choice of graft sources and are benchmarks for future graft-versus-host disease prophylaxis studies.

Graft-versus-Host Disease after HLA-Matched Sibling Bone Marrow or Peripheral Blood Stem Cell Transplantation: Comparison of North American Caucasian and Japanese Populations

The risk of acute graft-versus-host disease (GVHD) after HLA-matched sibling bone marrow transplantation (BMT) is lower in Japanese than in Caucasian patients. However, race may have differential effect on GVHD dependent on the graft source. North American Caucasian and Japanese patients receiving their first allogeneic BMT or peripheral blood stem cell transplantation from an HLA-matched sibling for leukemia were eligible. BMT was performed in 13% of the Caucasian patients and in 53% of the Japanese patients. On multivariate analysis, the interaction term between race and graft source was not significant in any of the models, indicating that graft source does not affect the impact of race on outcomes. The risk of grade III or IV acute GVHD was significantly lower in the Japanese patients compared with the Caucasian patients (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.57 to 0.96), which resulted in lower risk of nonrelapse mortality in the Japanese patients (HR, 0.69; 95% CI, 0.54 to 0.89). The risk of relapse was also lower in this group. The lower risks of nonrelapse mortality and relapse resulted in lower overall mortality rates among the Japanese patients. In conclusion, our data indicate that irrespective of graft source, the risk of severe acute GVHD is lower in Japanese patients, resulting in a lower risk of nonrelapse mortality.

Graft-versus-Host Disease after HLA-Matched Sibling Bone Marrow or Peripheral Blood Stem Cell Transplantation: Comparison of North American Caucasian and Japanese Populations

Graft-versus-Host Disease after HLA-Matched Sibling Bone Marrow or Peripheral Blood Stem Cell Transplantation: Comparison of North American Caucasian and Japanese Populations

Impact of Race on Graft-Versus-Host Disease Rates after HLA-Matched Sibling Bone Marrow or Peripheral Blood Hematopoietic Cell Transplantation: Comparison of North American Caucasian Versus Japanese Populations

s / Biol Blood Marrow Transplant 21 (2015) S30eS53 S35 grade 3-4 aGVHD post PBSC alloHCT was 14% and 10% in the Caucasians and Japanese, respectively (Figure 1B). In multivariate analysis, the interaction term between race and graft source was not significant in any of the models, indicating that the impact of race on outcomes does not differ according to graft source. The risk of grade 3-4 aGVHD was significantly lower in Japanese compared to Caucasians (HR 0.74, 95% CI 0.57-0.96), which resulted in lower risk of non-relapse mortality (NRM) in Japanese compared to Caucasian patients (HR 0.69, 95% CI 0.54-0.89). The risk of relapse was also lower in Japanese compared to Caucasian patients (HR 0.75, 95% CI 0.63-0.89). Lower risk of NRM and relapse resulted in lower overall mortality rates in Japanese compared to Caucasians (HR 0.70, 95% CI 0.59-0.83). The risk of grade 3-4 aGVHD was significantly higher in PBSC compared to BM alloHCT recipients (HR 1.63, 95% CI 1.202.20), which resulted in higher NRM (HR 1.31, 95% CI 1.041.65) in PBSC compared to BM alloHCT recipients. Conclusions: Irrespective of graft source, the risk of severe aGVHDwas lower in Japanese patients, which resulted in the lower risk of NRM. The risk of severe aGVHD was higher in the PBSC alloHCT recipients, which resulted in the higher risk of NRM.

Familial Haploidentical (FHI) T-Cell Depleted (TCD) with T-Cell Addback Stem Cell Transplantation for Patients with High-Risk Sickle Cell Disease (SCD) (IND 14359)

Allogeneic stem cell transplantation (AlloSCT) from HLA-matched unaffected sibling donors (MSD) has been successful for high-risk SCD, and is the only known curative therapy (Freed/Cairo et al, BMT, 2012). We have recently demonstrated 100% event free survival and absence of sickle cell symptoms following reduced toxicity conditioning and HLA matched sibling bone marrow or cord blood AlloSCT (Bhatia/Cairo et al, BMT, 2014). However, 5 out of 6 children who might benefit from this therapy lack an HLA matched family donor. Identifiable matched unrelated adult donors (URD) in this ethnic group are extremely limited and results from unrelated cord blood transplants are poor (Radhakrishnan K/Cairo et al., BBMT 2013, Kamani et al., BBMT, 2012). We previously demonstrated the use of positive CD34 selection followed by T cell add back (2 x 105 CD3/kg) from unrelated donors in pediatric recipients with both malignant and nonmalignant disease lead to 100% engraftment with minimal acute GVHD (aGVHD). In a high-risk FHI TCD thalassemia study, 16/22 cases engrafted without aGVHD and with 90% overall survival (Sodani et al., Blood, 2010). FHI TCD AlloSCT could expand the donor pool and improve outcomes for patients with high risk SCD.This SCD consortium trial is investigating the safety, feasibility, EFS, donor chimerism, graft failure, aGVHD and chronic GVHD (cGVHD), and infectious mortality after FHI TCD AlloSCT in high-risk SCD patients (Figure 1).High risk features included one or more of the following: ≥1 CVA, ≥2 ACS, ≥3 VOC in past 2 years, or 2 abnormal TCDs. Patients (2-20.99 yrs) without an 8/8 HLA MSD or URD and who have ≥1 high-risk SCD features were eligible. Patients received hydroxyurea 60 mg/kg/d and azathioprine 3mg/kg/d, day -59 – day -11, fludarabine (30mg/m2/d x5d), busulfan (3.2 mg/kg/d x4d [<4yrs of age: 4 mg/kg/d x4d]), thiotepa (10 mg/kg/d x1d), cyclophosphamide (50mg/kg/d x4d), R-ATG (2mg/kg/d x4d), and TLI (500cGy) followed by FHI T-cell depleted AlloSCT. AGVHD prophylaxis included tacrolimus single agent. We utilized the CliniMACS (IND 14359) to enrich for peripheral blood hematopoietic progenitor cells (HPC’s); target dose of 10 x 106 CD34+ cells/kg with 2 x 105 CD3+ T cells/kg added back as a final CD3/kg concentration.Six patients have received AlloSCT to date (Figure 2). All patients utilized maternal donors who encountered no complications during collection. All had early neutrophil engraftment (median day +9), ≥98% whole blood chimerism and ≥85% RBC donor chimerism, no aGVHD or cGVHD (Figure 2). One patient developed late hepatic SOS and died at day +59; the remainder are alive and free of disease (day +12 to +642). One more patient has been enrolled and has begun conditioning and others are in the early part of their transplant process.Early results indicate FHI TCD AlloSCT is feasible in high-risk SCD patients who lack a MSD or URD. A larger cohort with longer term follow-up is needed to assess long-term safety and outcomes (Supported by FDA 5R01FD004090 and a grant from Otsuka) (IND #14359 and NCT 01461837). http://www.sicklecelltransplantconsortium.org [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Autoimmunity due to RAG deficiency and estimated disease incidence in RAG1/2 mutations

Autoimmunity due to RAG deficiency and estimated disease incidence in RAG1/2 mutations

HLA-Matched Sibling Transplantation for Severe Aplastic Anemia: Impact of HLA DR15 Antigen Status on Engraftment, Graft-versus-Host Disease, and Overall Survival

The HLA class II DRB1 antigen DR15 (common alleles *1501, *1502) is an important marker in the pathobiology of severe aplastic anemia (SAA). We studied 1204 recipients of HLA-matched sibling bone marrow transplantation for SAA to determine whether HLA DR15 status (as determined by allele-level typing) affected hematopoietic recovery, graft-versus-host disease (GVHD), or overall survival (OS). In multivariate analysis, secondary graft failure rate at 2 years was lower in patients who were HLA DR15+ (hazard ratio = 0.46, P = .01). However, neutrophil recovery at day -28, platelet recovery at day -100, acute GVHD, chronic GVHD, and overall mortality were independent of DR15 status. The 5-year probabilities of OS, after adjusting for age, race, performance score, transplant-conditioning regimen, and year of transplantation, were 78% and 81% for patients who were HLA DR15+ and HLA DR15-, respectively (P = .35). In conclusion, DR15 status is associated with secondary graft failure after HLA-matched sibling bone marrow transplantation for SAA but has no significant impact on survival.

HLA-matched sibling bone marrow transplantation for β-thalassemia major

AbstractWe describe outcomes after human leukocyte antigen-matched sibling bone marrow transplantation (BMT) for 179 patients with β-thalassemia major. The median age at transplantation was 7 years and the median follow-up was 6 years. The distribution of Pesaro risk class I, II, and III categories was 2%, 42%, and 36%, respectively. The day 30 cumulative incidence of neutrophil recovery and day 100 platelet recovery were 90% and 86%, respectively. Seventeen patients had graft failure, which was fatal in 11. Six of 9 patients with graft failure are alive after a second transplantation. The day 100 probability of acute graft-versus-host disease and 5-year probability of chronic graft-versus-host disease was 38% and 13%, respectively. The 5-year probabilities of overall- and disease-free survival were 91% and 88%, respectively, for patients with Pesaro risk class II, and 64% and 62%, respectively, for Pesaro risk class III. In multivariate analysis, mortality risks were higher in patients 7 years of age and older and those with hepatomegaly before BMT. The leading causes of death were interstitial pneumonitis (n = 7), hemorrhage (n = 8), and veno-occlusive disease (n = 6). Proceeding to BMT in children younger than 7 years before development of end-organ damage, particularly in the liver, should improve results after BMT for β-thalassemia major.

A Pilot Study of Reduced Toxicity Conditioning (RTC) with Busulfan (Bu), Fludarabine (Flu), and Alemtuzumab Followed by Allogeneic Stem Cell Transplantation (AlloSCT) to Induce Sustained Mixed Donor Chimerism In Patients with Symptomatic Sickle Cell Disease (SCD)

AbstractAbstract 3504The only known curative therapy for patients with SCD is a matched family donor AlloSCT (Walters et al, NEJM, 1996). Complications after myeloablative AlloSCT are numerous and include death, graft versus host disease (GVHD), and infections, making reduced toxicity conditioning regimens more appealing. A major obstacle allowing most SCD patients to undergo SCT is the lack of an unaffected, HLA-matched identical sibling (Bhatia et al, BMT, 2008). Umbilical cord blood (UCB) has been proven to be an excellent alternate donor source that can safely reconstitute hematopoiesis after AlloSCT in pediatric recipients with non-malignant conditions (Cairo et al, BBMT, 2008). In this study, we report the results of a RTC regimen followed by an AlloSCT from matched family and unrelated UCB donors in selected patients with symptomatic SCD. Between August 27, 2004 and March 2, 2010, 18 patients (14M:2F) with symptomatic SCD (HbSS=10, HbSC=4, HbSßThal=4) underwent an AlloSCT. Indications for SCT included: ACS (n=8), CVA (n=2), multiple VOC (n=9), splenic sequestration (n=6) and retinopathy (n=1). Conditioning was Bu (4mg/kg × 4d < 4 yrs and 12.8mg/kg × 4d > 4 yrs), Flu (30mg/m2 × 6d), and Alemtuzumab (2mg/m2 × 1d, 6mg/m2 × 2d, and 20mg/m2 × 2d). Median age was 6.29 yrs(1.3–19.2). Median follow-up was 26 months. Donor sources: 8-6/6 HLA-matched sibling bone marrow (BM), 2–6/6 sibling UCB, 1–6/6, 4–5/6 and 3–4/6 unrelated UCB. Donors were HbAA (n=13), HbAC (n=1), HbAS(n=3), or ßThal trait (n=1). Sibling BM recipients received a median total nucleated cell (TNC) dose/kg of 7.16 × 108 (range 2.27–11.31) and a median CD34 cell dose/kg of 5.38 × 106 (range 1.50–6.83). Recipients of related or unrelated UCB received a median TNC dose/kg of 4.35 × 107 (range 3.40–9.10) and a median CD34 cell dose/kg of 2.21 × 105 (range 0.60–7.94). All received tacrolimus and mycophenolate mofetil as GVHD prophylaxis (Bhatia/Cairo et al, BBMT, 2009) and phenytoin or keppra as seizure prophylaxis for 180 days post SCT. Patients receiving sibling donor AlloSCT had a median time to neutrophil engraftment of 16 days (range 13–41). Among evaluable unrelated UCBT recipients, median time to neutrophil engraftment was 34 days (range 27–47). Four patients (all unrelated UCBT) experienced primary graft failure at day +60 post-SCT secondary to CMV (n=2), adenovirus, and low Bu Css levels with early withdrawal of MMF. Patients with sibling donors had a median time to platelet engraftment of 26 days (range 17–75). Of evaluable unrelated UCB recipients, median time to platelet engraftment was 54 days (range 43–70). Patients achieved mean whole blood donor chimerism of 71.0, 79.6, 85.7, 92.9, 90.7% and 93.2% at days 30, 60, 100, 180, 365 and 730 post-transplant, respectively. Mean erythroid (CD71) donor chimerism at these time points was 78.1, 81.1, 86.6, 90.5, 87.9% and 94.0%, respectively. Patients with non-sickle cell trait donors had median HbS levels of 0% at 1 yr (n=8) and 2 yrs (n=3) post-SCT; those with sickle cell trait donors had median HbS levels of 38.3% at 1 yr (n=3) and 39% at 2yrs (n=3) post-SCT. Among evaluable patients, the Kaplan-Meier probability of grade II-IV acute GVHD is 33.3% and of chronic GVHD is 8.3%. Among the ten donor-recipient pairs in which at least one member of the pair had CMV positivity, four experienced CMV reactivation on days +13, +26, +30 and +32 (BM: n=2, unrelated UCB: n=2). Of the four patients with primary graft failure (all unrelated UCBT recipients), one resumed chronic transfusions, two died of complications from disseminated CMV and adenoviral infections, and one received a second myeloablative SCT 1 yr after initial SCT and died of fungal sepsis. Among all patients, the Kaplan-Meier probability of OS is 81.8% (100% with sibling donors, 62.5% with UCB donors) and of EFS is 77.8% (100% with sibling donors, 50% with UCB donors) with none of these patients showing any evidence of SCD symptomatology post-SCT. The longest follow-up is 2134 days. In summary, we report the largest experience of RTC and matched family AlloSCT in selected children with symptomatic SCD with persistent long-term donor chimerism and absence of SCD symptoms or progression of disease. However, with the high incidence of viral infections and toxic deaths following unrelated UCBT, it is too premature to extend this treatment option to those SCD patients lacking a sibling donor. Disclosures:No relevant conflicts of interest to declare.

Comparison of Outcomes after Transplantation of G-CSF–Stimulated Bone Marrow Grafts versus Bone Marrow or Peripheral Blood Grafts from HLA-Matched Sibling Donors for Patients with Severe Aplastic Anemia

We compared outcomes of patients with severe aplastic anemia (SAA) who received granulocyte-colony stimulating factor (G-CSF)-stimulated bone marrow (G-BM) (n = 78), unstimulated bone marrow (BM) (n= 547), or peripheral blood progenitor cells (PBPC) (n = 134) from an HLA-matched sibling. Transplantations occurred in 1997 to 2003. Rates of neutrophil and platelet recovery were not different among the 3 treatment groups. Grade 2-4 acute graft-versus-host disease (aGVHD) (relative risk [RR] = 0.82, P = .539), grade 3-4 aGVHD (RR = 0.74, P = .535), and chronic GVHD (cGVHD) (RR = 1.56, P = .229) were similar after G-BM and BM transplants. Grade 2-4 aGVHD (RR = 2.37, P = .012) but not grade 3-4 aGVHD (RR = 1.66, P = .323) and cGVHD (RR = 5.09, P < .001) were higher after PBPC transplants compared to G-BM. Grade 2-4 (RR = 2.90, P < .001), grade 3-4 (RR = 2.24, P = .009) aGVHD and cGVHD (RR = 3.26, P < .001) were higher after PBPC transplants compared to BM. Mortality risks were lower after transplantation of BM compared to G-BM (RR = 0.63, P = .05). These data suggest no advantage to using G-BM and the observed higher rates of aGVHD and cGVHD in PBPC recipients warrants cautious use of this graft source for SAA. Taken together, BM is the preferred graft for HLA-matched sibling transplants for SAA.

Immunosuppressive Cytokine Gene Polymorphisms and Outcome after Related and Unrelated Hematopoietic Cell Transplantation in a Chinese Population

Cytokine gene polymorphisms can affect the outcome of allogeneic hematopoietic stem cell transplantation. We analyzed 6 single nucleotide polymorphisms in 3 immunosuppressive cytokine genes, TGFβ1-509(C>T), +869(T>C), TGFβ1 receptor II (TGFβ1RII) +1167(C>T, codon389 AAC/AAT), and IL-10-1082(A>G), -819(T>C), -592(A>C), in a cohort of 138 pairs of recipients and their unrelated donors and a second cohort of 102 pairs of recipients and their HLA-identical sibling donors. TGFβ1-509 T/T genotype in the donors or T allele-positivity in the recipients was associated with a significant protective effect against acute graft-versus-host disease (aGVHD) and grades II-IV aGVHD in the unrelated transplantation cohort. In the combined cohort, multivariate analysis confirmed that donors with the TGFβ1-509 T/T genotype also conferred protection against the risk of aGVHD and grades II-IV aGVHD. In both the unrelated transplantation cohort and the sibling transplantation cohort, the IL-10-819 C/C and -592 C/C genotypes in either recipients or donors were significantly associated with a higher incidence of aGVHD. In the combined cohort, the IL-10 promoter haplotype polymorphisms at positions -1082, -819, and -592 influenced the occurrence of aGVHD and death in remission. Recipients without the A-T-A haplotype or those transplanted from donors without the A-T-A haplotype had a higher incidence of aGVHD than those who were A-T-A homozygotes or heterozygotes. Estimates for death in remission showed a clear advantage for recipients transplanted from donors with the A-T-A haplotype. In multivariate analysis, recipients without the A-T-A IL-10 haplotype had a higher risk of aGVHD (relative risk [RR] = 0.764; 95% confidence interval [CI]: 0.460-1.269; P = .096) and grades II-IV aGVHD (RR = 0.413; 95% CI: 0.245-0.697; P = .001). These results provide the first report of an association between TGFβ1, TGFβ1RII, and IL-10 polymorphic features and outcome of allo-HSCT in a Chinese population, and suggest an interaction between TGFβ1-509 genotypes and IL-10 promoter haplotype polymorphisms at positions -1082, -819, and -592 and the risk of aGVHD.

Response of 864 Patients to Steroids as Primary Therapy for Acute Gvhd at a Single Institution: Day 28 Response Is the Best Endpoint to Predict Transplant-Related Mortality.

Abstract 1134Poster Board I-156The optimal primary endpoint for acute GVHD treatment trials has not been established. In a retrospective analysis, we examined the response of 864 patients who received prednisone 60 mg/m2 for 14 days, followed by an 8 week taper, as initial therapy for acute GVHD from 1990-2007 at a single institution. Complete response (CR), partial response (PR), very good partial response (VGPR), and no response (NR) were scored at day 14, day 28 and day 56 after initiation of steroids. To determine the best endpoint, an index of concordance, the c-statistic (C), was performed to estimate the probability that patients with the better GVHD response will have lower transplant related mortality (TRM) than patients with a worse response. Median patient age was 32 (range, 0.2-69) years; 35% were <18 years old. Patients received grafts of HLA-matched sibling bone marrow (BM) or peripheral blood (PB, n=315), partially matched sibling BM or PB (n=24), unrelated donor (URD) BM or PB (n=313), single umbilical cord blood (sUCB, n=89) or double UCB (dUCB, n=123). Prior to initiation of steroid therapy, initial GVHD grades were grade I in 230 (27%), grade II in 504 (58%), grade III in 119 (14%), and grade IV in 11 (1%). Initial GVHD organ involvement was skin only (57%), gut only (17%), liver only (1%) or multiorgan (25%). Day 28 responses were similar to day 56 responses (p=0.14) and better than day 14 responses (p=0.03) in predicting TRM. In multiple regression analysis, patients with NR at day 28 were 2.77 times more likely to have TRM than patients with CR, VGPR or PR while any response favored lower TRM (table). Factors associated with significantly worse 2 year TRM in patients with acute GVHD include: NR to steroids, partially matched BM/PB, high risk disease, older age and skin only GVHD. Factors not associated with TRM include CMV serostatus, conditioning therapy, GVHD prophylaxis, days to steroid treatment, and initial grade of GVHD.Table:Factors associated with 2 year TRM: multiple regression analysisFactorRelative RiskP valueOverall P ValueDay 28 Response (% patients)..<0.001CR (53%)1.0.VGPR (7%)0.630.13PR (4%)1.220.45NR (31%)2.77<0.001Donor Type..<0.01MSD BM/PBSC1.0.URD well matched BM/PBSC1.350.17URD partial matched BM/PBSC1.540.03URD or sibling MM BM/PBSC1.77<0.001Single UCB1.060.83Double UCB0.790.36Disease Risk..0.02Standard1.0.High1.350.02Age1.00.020.02<18 years1.40318 yearsAffected Organs (skin only)..0.05Yes1.0.No1.360.05Grade at Start of Steroid Therapy..0.11I1.0.II1.080.60III-IV1.510.10These data suggest that responses at day 28 or 56 are equally effective endpoints for acute GVHD trials. Day 14 responses cannot as accurately predict TRM. As patients with NR require further therapy in a timely manner, early progression or response by day 28 is the best endpoint to assess efficacy of initial therapy for acute GVHD. Prospective trials are still required to determine the best therapy for different subgroups of patients with acute GVHD, especially those identified to have predictably poor responses and high TRM. DisclosuresNo relevant conflicts of interest to declare.

Promising approach for aggressive NK cell leukaemia with allogeneic haematopoietic cell transplantation

Aggressive natural killer cell leukaemia (ANKL) is a malignant disorder of mature NK cells with a poor prognosis, for which no effective therapeutic approach has been established. We investigated the role of allogeneic haematopoietic cell transplantion (allo-HCT) in ANKL. Three patients with ANKL received allo-HCT and seven did not. Epstein-Barr virus (EBV) viral load (VL) of the whole blood was measured with real-time quantitative polymerase chain reaction. We transplanted three patients using a myeloablative conditioning regimen with human leucocyte antigen (HLA) two-loci mismatched cord blood (n = 2), or HLA-matched sibling bone marrow (n = 1). In one patient, a second transplantation from the haploidentical mother was also performed at relapse. No patients were in complete remission (CR) at the time of conditioning. After allo-HCT, all three achieved and maintained CR. One died from sepsis and the other relapsed, received the second transplantation and achieved a second CR. EBV VL was quite high in all three at presentation and its significant reduction was observed after allo-HCT. Although their backgrounds were not different from those without allo-HCT, patients with allo-HCT had a better outcome. Allo-HCT might be a promising therapy for ANKL with curative potential.

Risk Factors and Outcome after Second HLA-Matched Sibling Donor Transplantation for Graft Failure after a First HLA-Matched Sibling Transplant in Severe Aplastic Anemia.

Graft failure rates after HLA matched sibling bone marrow (BM) transplants for severe aplastic anemia (SAA) are about 10%. We analyzed factors that may affect rates of hematopoietic recovery, graft-versus-host (GVHD) and overall survival after a second HLA-matched sibling donor transplant in 166 patients with SAA with graft failure after a first HLA-matched sibling donor transplant. Transplantations occurred between 1986 and 2004; median follow up of surviving patients is 8 years. One hundred and forty patients (84%) received their second transplant for secondary graft failure and 26 (16%), for primary graft failure. The median age at second transplantation was 17 years; 90% of patients were younger than 30 years. Sixty-seven percent had performance scores <90%. All patients received T-replete BM grafts for their first transplant; 16% received peripheral blood progenitor cells and 84% BM for their second transplant. Most (88%) second transplants used the original donor. Median time between first and second transplants was 7 months (range 1 – 114). Seventy-four percent received cyclophosphamide (CY) with or without anti-thymocyte globulin (ATG) conditioning for their first transplant. Forty-nine percent received this regimen for second transplant, 19% received CY and limited field irradiation, 10%, busulfan and CY, 11% melphalan and ATG, 4% other combinations of CY and 7% did not receive a second conditioning regimen. For both transplants, most patients (>95%) received GVHD prophylaxis regimen that included a calcineurin-inhibitor. Probabilities of neutrophil recovery at day 28 and platelet recovery at day 60 after second transplantation were 63% and, 62%. Rates of acute grades 2–4 GVHD at day 100 and chronic GVHD at 5 years were 9% and 16%, respectively. Early mortality rates were high, 30% at day-100. Risks of early mortality were lower when pre-transplant performance scores were 90–100% (relative risk [RR] 0.17, 95% CI 0.06–0.47, p=0.001) and when second transplant occurred >3 months from first transplant (RR 0.32, 95% CI 0.15–0.68, p=0.003). Similarly, risks of overall mortality were lower in patients with performance scores 90 – 100% (RR 0.53, 95% CI 0.30–0.95, p=0.033) and when second transplant occurred >3 months from first transplant (RR 0.47, 95% CI 0.29–0.76, p=0.002). Of the 47 patients who received their second transplant ≤ 3 months after their first transplant, 22 had primary graft failure after their first transplant and 25, early secondary graft failure. Fifteen of these 47 patients failed to achieve neutrophil recovery after their second transplant; 12 of 15 had primary graft failure after first transplant. Other factors such as use of a different donor, conditioning regimen, graft type and growth factor administration did not affect outcome after second transplantation. The 5-year probabilities of overall survival in patients with performance scores 90–100% whose second transplants occurred ≤ 3 months and >3 months after their first transplant were 56% and 76%, respectively. Corresponding rates for patients with performance scores <90 were 33% and 61%. We conclude that salvage with second transplantation after primary or early secondary graft failure is suboptimal. Better therapies are required to ensure sustained hematopoietic recovery in these patients.

Risk Factors for Graft Failure and Mortality after HLA-Matched Sibling Donor Transplant for Severe Aplastic Anemia in Brazil.

Higher rates of graft failure observed after conventional cyclophosphamide (Cy) at 200mg/kg and HLA-matched sibling bone marrow transplant (BMT) for severe aplastic anemia (SAA) in South America prompted the use of a different conditioning regimen: busulfan (Bu) at 12 mg/kg plus Cy at 120 mg/kg. This change was instituted to provide greater immunosuppression for heavily transfused patients (>15 blood transfusion units pre-BMT). We report transplant outcomes in 269 SAA patients who received their HLA-matched BMT at a single center in Brazil between 1990 and 2003. Median age at transplant was 19 years (range 2 – 45). Median time from diagnosis to transplant was 3 months; 78% were transplanted ≤ 6 months from diagnosis, 11%, 7–24 months and 11% > 24 months. 128 patients received Cy alone, 2, Cy plus anti-thymocyte globulin and 139, Bu plus Cy. Eighty-one patients (62%) who received Cy conditioning also received ≤15 blood transfusion units and 49 (38%) received >15 blood transfusion units pre- BMT; all patients who received Bu plus Cy conditioning received >15 blood transfusion units. All patients received T-cell replete bone marrow grafts and almost all patients received cyclosporine and short course methotrexate for graft-versus-host disease prophylaxis. Median follow-up of surviving patients after Cy is 9 years and after Bu plus Cy, 6 years. This reflects the change in practice after 1994, when Bu plus Cy was favored for patients who received >15 blood transfusion units pre-BMT. Most patients achieved neutrophil recovery; the day-60 probabilities of recovery were 95% and 86% after Cy conditioning (≤15 and >15 blood transfusion units, respectively) and 92% after Bu plus Cy. Corresponding day-100 probabilities of platelet recovery were 95%, 86% and 87%. Thirty-nine patients subsequently lost their graft; failure rates were similar after Bu plus Cy and Cy conditioning in patients who received ≤15 blood transfusion units (13% vs. 17%; RR 0.97, p=0.924). Though failure rates were higher (10 of 42, 24%) after Cy conditioning in patients who received >15 blood transfusion units this did not attain statistical significance when compared to those who received Bu plus Cy (16 of 128, 13%, p=0.077). This may be explained by limited numbers of patients in the heavily transfused Cy group. Younger age (≤10 years) was the only factor that was associated with higher rates of secondary graft failure (RR 2.91, p=0.001). As expected, the 8-year probability of overall survival was highest (87%) after Cy conditioning in patients who received ≤15 blood transfusion units. Mortality rates were higher after Bu plus Cy conditioning (RR 3.18, p<0.001) and Cy conditioning in patients who received > 15 blood transfusion units (RR 4.66, p<0.001). The corresponding 8-year probabilities of overall survival were 67% and 51% (p=0.059). The data suggest secondary graft failure rates are similar after Bu plus Cy conditioning in patients who received >15 blood transfusion units compared to those who received Cy conditioning and fewer transfusions. Though survival rates are generally lower in patients who receive >15 blood transfusion units, the use of Bu plus Cy appears to confer a survival advantage. Patients with SAA should be referred for transplantation as soon as the diagnosis is confirmed to avoid excess blood transfusion pre-BMT.

Gentuzumab Ozogamicin (GO:Mylotarg) Monotherapy for Relapsed AML after Hematopoietic Stem Cell Transplantation: from Morphological Target to Molecular Target.

Background: The treatment for acute myeloid leukemia patients with relapse after stem cell transplantation is limited to dose reduction of immunosuppressive agents, donor leukocyte infusion (DLI), and a second transplantation. The prognosis of such patient is very poor if these therapies cannot be tolerated or are unsuccessful. Gentuzumab ozogamicin(GO) is an antibody targeted chemotherapy consisting of a humanized anti-CD33 monoclonal antibody linked to calicheamycin. The CD33 antigen is expressed on most AML cells and myeloid progenitor cells, but is not expressed on lymphocytes which play an important role in GVL effect. Therefore, GO can potentially eradicate AML cells without harming these lymphocytes.Patients: We retrospectively studied 9 patients with AML, who relapsed following allogeneic stem cell transplantation (SCT) and had difficulty tolerating DLI. Their donor sources included one 6/6 HLA-matched sibling bone marrow cells, four 6/6 HLA-matched unrelated bone marrow stem cells, and four 4/6 HLA-matched unrelated cord blood. The status of leukemia at SCT was 1st complete remission (CR) in one patient, 2nd CR in one patient, and active disease in seven patients. Treatment protocol: GO was administered at 6 mg/m2 for 2 doses separated by 2 weeks. Treatment was initially performed at morphological relapse but after April 2006 patients received treatment at molecular relapse. The molecular relapse was diagnosed by the quantitative expression of WT1 (Wilms tumor gene). (Blood. 2003; 101:1698–1704)Results: Five patients were treated at morphological relapse (group A) and four patients were treated at molecular relapse (group B). Eight received both doses of GO. The period from SCT to relapse ranged from 36 days to 193 days (median: 85 days). The period from SCT to GO administration ranged from 54 days to 229 days (median: 98 days). Seven of 9 patients achieved a remission (3/5 in group A, 4/4 in group B). Three CR patients in group A relapsed (day 48, 95, and 106, respectively). All of the patients in group A died within 447 days. (at 42 days, 131 days, 158 days, 173 days and 447 days, respectively, after GO). Two of the 4 patients in group B relapsed, one on day 300 and one on day 350. One patient died in CR from multiple organ failure following CMV infection; the fourth patient is still in CR. Three patients in group B are alive at 276 days, 410 days, and 443 days. Three patients developed infusion-related fever, one patients nausea. All patients developed grade 4 neutropenia and thrombocytopenia. Febrile neutropenia was observed in four patients. Five patients developed elevation of ALT, grade 3 in 1 patient and grade 1 in 4 patients. Three patients developed grade 1 hyperbilirubinemia. Only one patient developed reversible VOD. VOD occurred on thirteenth day after the administration of GO. The period between SCT and GO administration was 77 days.Conclusion: The administration of GO is effective in inducing remission in relapsed AML patients after SCT. The ability of GO therapy to induce durable response may possibly be enhanced by early therapeutic intervention before the onset of hematologic relapse. This approach is feasible and well tolerated with minimal toxicity. Additional studies in a large group of patients will be required to adequately assess the safety and efficacy of this approach.

Elevated lactate dehydrogenase is an adverse predictor of outcome in HLA-matched sibling bone marrow transplant for acute myelogenous leukemia

Prognostic factors for survival following allogeneic BMT for AML include age, disease status and cytogenetic risk classification. Lactate dehydrogenase (LDH) levels have not been studied as a potential risk factor. We reviewed our experience with BMT for AML and included LDH at the time of admission in an analysis of prognostic factors for survival. We found that LDH >330 U/l (1.5 times the upper limit of normal at our institution), older age, active disease, peripheral stem cell graft and male-to-male transplant were significant adverse predictors of survival. After accounting for LDH, other factors such as disease status and cytogenetics were not significantly associated with the outcome of BMT. All but one patient with an LDH >330 U/l had active disease. However, when patients in CR were excluded, LDH >330 U/l remained a significant adverse predictor of overall survival (hazard ratio 2.70, 95% confidence interval 1.41-5.16, P=0.003). We conclude that LDH is an important adverse risk factor for survival and should be included in future studies of risk performed on larger patient cohorts.

60: A high lactate dehydrogenase (LDH) level predicts for shorter survival following HLA-matched sibling bone marrow transplant (BMT) for patients with acute myelogenous leukemia (AML)

Historically, the most important adverse risk factors for survival after BMT for AML are Active disease (ActDis), poor-risk cytogenetics, and older age. High serum LDH at the time of diagnosis is an adverse risk factor for survival for AML in the absence of BMT, but has not been explored as a risk factor in setting of BMT. We performed a multivariable analysis of these and other potential risk factors for overall and progression-free survival. From August 1992 to July 2005, we treated 87 patients with AML, who also had informative cytogenetic studies from the time of diagnosis, with high-dose busulfan-containing preparative regimens and an HLA-matched sibling BMT.

Lactate Dehydrogenase (LDH) Level Predicts the Outcome of Patients with Acute Myelogenous Leukemia (AML) Following HLA-Matched Sibling Bone Marrow Transplant (BMT).

Active disease (ActDis), poor-risk cytogenetics, and older age have historically been considered the most important adverse risk factors for survival after BMT for AML. We performed a multivariable analysis of these and other potential risk factors for overall and progression-free survival. From August 1992 to July 2005, we treated 87 patients with AML, who also had informative cytogenetic studies, with high-dose busulfan-containing preparative regimens and an HLA-matched sibling BMT. The median age was 43 years (range 19 to 62). The median LDH level at the time of BMT was 204 U/L (range 93–1555 U/L; normal 100–220 U/L). Forty-one patients were in either first (n= 30) or second complete remission (n=11; CR). 46 patients with ActDis were treated. The 87 patients were then classified according to the SWOG/ECOG (Blood 96:4075, 2000), MRC (Blood 92:2322, 1998), and CALGB (Blood 100:4325, 2002) cytogenetic classification systems. With a median follow-up of 56.0 months (range 4.5–107.8 months), the median relapse-free survival is 13.5 months for patients in CR1 and 4.1 months for patients in CR2. The relapse-free survival of patients with ActDis was 5.5 months. A Cox proportional hazards analysis that included gender, age, LDH, disease status, cytogenetic risk group, preparative regimen, source of stem cells, and CMV status was performed for overall and relapse-free survival. Significant risk factors for shorter survival in univariate analysis included male gender, LDH >330 U/L (but not LDH >220 U/L or per 100 U/L increase), and peripheral stem cells as a source of hematopoietic reconstitution (n = 7). Surprisingly, a male donor to a male recipient was also an adverse risk factor (p<0.001). However, in multivariable analysis, only LDH >330 U/L (p=0.002), source of stem cells (p=0.019), and male donor to male recipient (p<0.001) remained as significant adverse risk factors. In fact, patients with ActDis and an LDH ≤ 330 U/L had similar survival to patients treated in remission, while patients with ActDis and LDH > 330 U/L had significantly worse survival as shown below. We conclude that high LDH (>1.5X upper limit of normal) is a significant adverse risk factor for survival after BMT for AML and predicts outcome better than more traditional risk factors such as age, disease status, and cytogenetic risk profile. [Display omitted]