T-cell Replete Research Articles

HLA Mismatch Allogeneic Blood and Marrow Transplantation

A full haplotype mismatch or mismatched unrelated donor transplantation nowadays are well being focused on, as main alternative donor tools for acute leukemia patients in desperate need of allogeneic blood and marrow transplantation (BMT), the ability to overcome various posttransplant complications by adopting the T-cell replete technique in reality. Increasing numbers of allogeneic BMT in good clinical status are largely because it`s the best post-remission therapy especially for many patients with acute leukemias. Due to the problems of unavailable donors at appropriate clinical condition and the process of long duration of donor searching step with relatively much higher cost, some of physicians have indulged in haploidentical BMT rather than mismatched unrelated BMT. Both myeloablative and reduced intensity conditioning regimens for mismatched BMT with T-cell replete or T-cell depletion method have been exploited worldwide. Most of all, Asian countries have experienced lower rates of severe acute and chronic GvHD, graft failure, and impressively low transplant-related mortality with longer follow-up duration. Also, we need many future trials to compare outcomes between these two transplant modalities with cord blood transplant in various diseased patient populations. (Korean J Med 2014;86:1-13)

“Designed” grafts for HLA-haploidentical stem cell transplantation

Today human leukocyte antigen-haploidentical transplantation is a feasible option for patients with high-risk acute leukemia who do not have matched donors. Whether it is T-cell replete or T-cell depleted, it is still, however, associated with issues of transplant-related mortality and posttransplant leukemia relapse. After reports that adoptive immunotherapy with T-regulatory cells controls the alloreactivity of conventional T lymphocytes in animal models, tomorrow's world of haploidentical transplantation will focus on new "designed" grafts. They will contain an appropriate ratio of conventional T lymphocytes and T-regulatory cells, natural killer cells, γ δ T cells, and other accessory cells. Preliminary results of ongoing clinical trials show the approach is feasible. It is associated with better immune reconstitution and a quite powerful graft-versus-leukemia effect with a low incidence of graft-versus-host disease and no need for posttransplant pharmacological prophylaxis. Future strategies will focus on enhancing the clinical benefit of T-regulatory cells by increasing their number and strengthening their function.

Transplant Outcomes For Patients With AML/MDS Using Melphalan-Based Conditioning

IntroductionHaploidentical stem cell transplant (haplo-HCT) is a therapeutic option for patients without matched donors. We aimed to analyze outcomes of patients with AML/MDS treated with melphalan-based conditioning and different donors at our institution and determine the factors associated with survival. MethodsAll 246 patients receiving an allograft for AML/MDS between 01/2005 and 09/2012 were included in this retrospective analysis. Conditioning regimen consisted of melphalan 100 mg/m2 (Mel100) (N=37) or 140 mg/m2, (Mel140) (N=209) and fludarabine 120-240 mg/m2 +/- thiotepa (N=50). Graft versus host disease (GvHD) prophylaxis had consisted of tacrolimus and mini-methotrexate +/- ATG for matched transplants, and post-transplant cyclophosphamide (PTCy), tacrolimus and mycophenolate mofetil (MMF) for T-cell replete (TCR) haploidentical transplants. A small number of patients (N=19) received a T-cell depleted (TCD) haplo-HCT using CD34+ selected graft as previously described by us. We analyzed transplant outcomes and performed lymphocyte reconstitution on available samples from MRD, MUD and TCR-haplo recipients between day+30 and +365 post-transplant. Incidences in GvHD were assessed using Fisher's exact test. Differences in CD3+ T-cell counts were assessed using Kruskal-Wallis test. Kaplan-Meier survival curves were used to estimate OS, and PFS and the log-rank test was used to assess differences between groups; NRM was determined by the cumulative incidence (CI) function using the competing risks method. The competing risk included was relapse. Differences in cumulative incidence NRM between groups were assessed using Gray's test. ResultsMedian follow-up for survivors was 31 months. PFS for the entire cohort at 1 year was 44% and OS was 53%. No differences in outcomes (NRM, relapse, PFS) were noted for patients treated with ablative (140 mg/m2) or reduced dose (100mg/m2) of melphalan, both overall and for patients in remission(Fig.1A). To appreciate the impact of different donor type of transplant outcomes we analyzed outcomes of patients treated in remission (CR1+CR2) (N=78). Pre-transplant characteristics were well balanced for patients who received a MSD, MUD or haplo donor except TCR haplo patients received almost exclusively a bone marrow graft (95%) and TCD-haplo patients had a younger median age at transplant (27.5 years; P=0.0004). For patients in remission at transplant, 1 year PFS was 67% (Mel100) vs. 69% (Mel140) (P=0.97). Based on donor type, the 1-year PFS were 80% for MRD (N=25) recipients, 76% for MUD (N=26) recipients, 64% for TCR haplo (N=19) and only 13% for TCD-haplo recipients (N=8) (P=0.003) (Fig.1B). [Display omitted] In univariate and multivariable analyses for PFS, the only significant factors associated with worse survival were cytogenetic risk category and the use of a TCD haplo-HCT (Fig.1C). Using MUD donor as reference, no differences were detected in PFS when compared with recipients of MRD or TCR-haplodonors, while TCD-haplo group did significantly worse (multivariable analysis; P=0.006).The CI NRM rates for CR1+CR2 patients at 100 days were 0% (MRD), 5% (TCR-haplo), 4% (MUD), 38% (TCD-haplo), and at one year were 8% (MRD), 18% (TCR-haplo), 8% (MUD), and 75% (TCD-haplo) (P=0.0008).Incidence of severe aGvHD was 0% (TCR-haplo), 4% (MUD, MRD), and 50% (TCD-haplo) (P=0.0008). Overall chronic GvHD incidence was lowest in the TCR-haplo group (16%) and highest in the MRD group (48%). TCD-haplo and MUD had cGvHD rates of 25% and 34%, respectively (P=0.16).As shown in Fig.1D, TCR-haplo recipients reconstituted lymphocyte subsets with a kinetic trend similar to MUD and MRD recipients. All patients achieved normal CD3+ T-cell counts around day 180 post-transplant, with an early recovery of CD8+ T cells. TCR-haplo recipients did not have a significant inferior reconstitution for CD4+, CD8+, CD3-CD56+ and CD3-CD20+ cells at any time point between day 90 and day 365. ConclusionsOutcomes of patients with AML/MDS treated with melphalan-based conditioning are negatively influenced by cytogenetic risk category and the use of a TCDhaplo donor, while melphalan dose and the use of a TCR haplo-HCT vs. matched donor did not negatively impact survival. Disclosures:No relevant conflicts of interest to declare.

Outcomes Of Nonmyeloablative (NMA) Haploidentical Blood Or Marrow Transplantation (haploBMT) With High-Dose Posttransplantation Cyclophosphamide (PT/Cy) For Lymphoma

▪ BackgroundWith recent advances in GVHD prophylaxis, NMA haploBMT has become a viable option for pts who lack a fully matched donor. However, relatively few data are available on disease-specific outcomes following NMA haploBMT. This study evaluated the outcomes of NMA related haploBMT with PT/Cy in pts with lymphoma. Patients and methodsWe retrospectively analyzed 151 consecutive pts with poor-risk or advanced lymphoma who received NMA related haploBMT with PT/Cy at Johns Hopkins, without protocol-specified posttransplantation rituximab. Pts had a first-degree related haplo donor (allele or allele-group level typing at HLA-A, -B, -Cw, -DRB1, -DQB1), ECOG PS ≤ 1 or 2, LVEF ≥ 35%, adequate pulmonary and renal function, and in general ≥ PR for aggressive NHL, ≥ SD for Hodgkin lymphoma (HL). Conditioning consisted of Cy (14.5 mg/kg IV, days -6 and -5), fludarabine (30 mg/m2 IV, days -6 to -2), and TBI (200 cGy, day -1) in 98% of cases. Grafts were T-cell replete (bone marrow in 99%). GVHD prophylaxis consisted of high-dose PT/Cy (50 mg/kg IV) either once (day 3; 1 pt) or twice (days 3 and 4; 150 pts), mycophenolate mofetil, and tacrolimus. ResultsOf the 151 pts (median age 55, range 14-73 y), 52 (34%) had prior autologous BMT. By Disease Risk Index (DRI) categorization (Blood 2012;120(4):905), 38 pts (25%) were high-risk, 89 (59%) intermediate-risk, and 24 (16%) low-risk. There were 38 cases (25%) of HL; 53 cases (35%) of aggressive NHL including 28 B-cell, 24 T-cell, and 1 anaplastic nos; 20 cases (13%) of mantle cell lymphoma (MCL); 39 indolent histologies (17 CLL, 19 FL, 3 other); and 1 case of HL evolved from CLL. With a median follow-up of 3.8 (range 0.5 - 8) y in event-free pts, the 3-y probabilities of both progression-free survival (PFS) and disease-free survival were 40 (95% CI, 32-48)%, with a 3-y overall survival (OS) probability of 46 (39-55)% (figure A). The probability of neutrophil recovery was 88% at day 30 (median 17 days), and the probability of platelet recovery ≥ 20,000/µL was 86% at day 60 (median 26 days). Nonengraftment attributed to primary graft failure or to residual bone marrow malignancy occurred in 17/147 evaluable pts (12%), 8 with CLL. By competing-risk analysis, 1-y probabilities of nonrelapse mortality (NRM) and relapse were 16 (95% CI, 10-22)% and 31 (23-38)%, respectively. The probability of grade 2-4 acute GVHD was 32 (95% CI, 24-39)%, grade 3-4 acute GVHD was 5 (1-8)%, and chronic GVHD was 13 (7-18)%. Disease-specific cumulative incidences of relapse, estimated by competing-risk analysis, are shown in figure B. The 3-y probabilities of PFS and OS were 53 (95% CI, 39-72) and 67 (53-84)%, respectively, in HL; 35 (25-51)% and 38 (26-54)% in aggressive NHL; 23 (9-54) and 28 (13-62)% in MCL; and 42 (29-61)% and 48 (34-67)% in indolent NHL and CLL combined. On unadjusted landmark analyses, we found no statistically significant association between PFS and the development of grade 2-4 acute GVHD treated as a time-independent variable. On unadjusted analysis, the DRI category (low, intermediate, or high) was among the variables statistically significantly associated with PFS (p = 0.02; figure C), and remained independently associated with PFS on multivariate analysis adjusted for pt age (p = 0.002). [Display omitted] ConclusionsNMA related haploBMT with PT/Cy carries acceptable toxicities that parallel those of NMA matched transplants, while producing durable disease control in a clear subset of lymphoma pts. This approach facilitates the integration of new posttransplantation strategies that could reduce the risk of relapse. Disclosures:Off Label Use: posttransplant cyclophosphamide for GVHD prevention.

Overall and Disease-Specific Outcomes Following T-Cell Replete Haploidentical Transplants Using Post-Transplant Cyclophosphamide: An Analysis Of 115 Patients Transplanted At a Single Center

Many patients with hematologic malignancies who may benefit from the curative potential of allogeneic hematopoietic cell transplantation (allo-HCT) will lack a conventional matched sibling (MRD) or matched unrelated (MUD) donor. An HLA-haploidentical related donor is available for nearly all such patients. Attempts to use haploidentical donors that employ stringent ex-vivo T-cell depletion to abrogate GVHD are associated with poor immune reconstitution and high rates of graft rejection. In contrast, the recent use of T-cell replete grafts with post-transplant cyclophosphamide (haplo-ptCy) has resulted in effective control of alloreactivity with low rates of post-transplant infection, graft-rejection and non-relapse mortality using both non-ablative and ablative regimens (Luznik at al BBMT 2008, Solomon et al BBMT 2012.). We recently demonstrated similar outcomes for 53 haplo-PtCy to contemporaneous MRD and MUD transplants performed at our enter (Bashey et al JCO 2013). However there are limited data with respect to the outcome of specific hematologic malignancies using haplo-ptCy. For this study all consecutive patients who underwent haplo-ptCy as a first allogeneic transplant at our center between Oct 2005 and May 2013 (n=115) were included [median age 50 (20-74); M 57%, F 43%; diagnosis- AML(38), ALL(20), CLL(13), NHL(13) HL(10), CML+MPS (12), MDS (7) others (2); graft-BM(58%),PBSC(42%); prior autotranplant(18%); CIBMTR disease risk score high(35%), intermediate(32%) low(33%). Sorror Comorbidity Index-median =1(0-5)]. Preparative regimens used included non-myeloablative [fludarabine 30 mg/m2/d d -6 to -2; TBI 200cGy d-1, Cy 14.5 mg/kg/d on d-6,-5 and 50mg/kg/d on d+3,+4, n=73 ] and myeloablative [regimen 1- same as non-ablative except busulfan 110-130 mg/m2 /d i.v. on d-7 to-3 instead of TBI n=21; regimen 2- fludarabine 30 mg/m2/d d -7 to -5, TBI 150cGy bid x 8 doses (total dose =1200cGy) and Cy 50mg/kg/d d+3,+4 n=21]. Patient characteristics and outcome data were collected prospectively and obtained from our comprehensive database. Survival and disease-free survival (DFS) were estimated using the Kaplan-Meier method. Cumulative incidence of non-relapse mortality (NRM) was calculated using relapse as a competing risk. GVHD was assessed and documented prospectively by a dedicated GVHD nurse. Median CD34+ and CD3+cell doses infused were 4.21 x 10e6/kg (0.84-8.13) and 5.81 x 10e7/kg (1.4-59.5). median time to ANC > 500/mm3 and platelets > 20,000/mm3 were 16 and 26 d. Median % donor chimerism on d 30 were 100% and 100% for PB CD3+ and CD33+ cells respectively. With a median follow-up for living patients of 20 months, the 12 m and 24 m cumulative incidences (CI) of NRM were 10% and 18% and of relapse/progression were 25% and 25% respectively (Fig.1). CI of acute GVHD gd II-IV and gd III-IV at 6 m were 34% and 13% respectively, and of extensive and severe chronic GVHD at 12 m were 40% and 9% respectively. Estimated 12m and 24m probabilities of survival were 73% and 56% and of DFS were 65% and 57% respectively. On a Cox multivariate analysis assessing patient, disease and transplant related covariates, high risk CIBMTR disease score (HR 1.88, p=0.043) and acute GVHD gd 3-4 HR=2.54, p=0.0145) were the only factors significantly associated with survival. For the most frequently treated diagnoses - AML, ALL and mature lymphoid malignancies (CLL, NHL, HL) - the respective estimated 24 m probabilities of DFS were 61%, 58% and 50% respectively (Fig.2). These data demonstrate that haplo-ptCy transplants represent a safe and effective alternative for most patients who may benefit from allo-HCT but lack a conventional donor. They should be offered as standard of care in such patients. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Higher Prevalence But Similar Infectious Profile Overtime After Haploidentical Transplantation Compared With HLA-Identical Transplantation For Hematological Diseases

Introduction a major limitation of hematopoietic stem cell transplantation (HSCT) from haploidentical donor is the impaired immune reconstitution due to extensive immunosuppression necessary to overcome HLA disparity. Recently, a platform for T-cell repleted HSCT from haploidentical donor (haplo-HSCT) using post-transplant cyclophosphamide (CTX) has been reported, with low TRM and high reproducibility. However, little has been reported so far about immune reconstitution and, in particular, incidence of infections after this type of transplantation. Aims of the study to describe infectious complications after T-cell replete haplo-HSCT after NMA conditioning performed at our center and to compare them with HLA-identical transplantations performed at the same center. Patients and Methods data on patients with hematological malignancies who underwent haplo-HSCT were collected and compared with RIC/NMA-HSCT from HLA-identical donors. Transplants included were those performed up to 31st December 2012. Infections were classified as FUO, bacterial, micotic or viral and prevalence over five post-transplant intervals was estimated: days 0-30, 31-100, 101-180, 181-365, >365. Prevalence for each time period was defined as the number of infectious events/patients at risk. Results we identified a total of 72 and 40 patients transplanted from HLA-identical or haploidentical donor respectively. Median follow-up was longer in HLA-identical vs. haploidentical (34 vs. 15 months, p<0.0001). Among 38 out of 40 haplo-HSCT patients, a total of 96 infectious events occurred, with a median of 3 events/patient (range: 0-6). Etiologies were as follows: 39 bacterial, 6 fungal and 51 viral. Bacterial infections occurred mostly between day 0 and +30, whereas viral infections/reactivations between +30 and +100 (see Figure 1a). In the HLA-identical cohort, 166 events occurred among 64 out of 72 patients, with a median of 2 events/patient (range: 0-8); etiologies were: 84 bacterial, 9 fungal and 73 viral. FUO events were 19 and 34 among haplo- and HLA-identical transplants respectively. Prevalence of infections was lower in HLA-identical compared with haplo-HSCT group, but subdistribution of etiologies was similar overtime (see Figure 1b), with bacterial and FUO mostly before day+30 and viral events mostly between +30 and +100. Importantly, no fungal infections occurred beyond day +180 in haplo group, probably due to the low incidence of chronic GVH. Conversely, higher prevalence of bacterial events observed in HLA-identical group may be due to chronic GVH. Deaths due infection were 25% in haplo group (10/40, occuring between +13 and +152) and 11% (8/75) among HLA-identical transplants. Conclusion RIC haplo-SCT with post-transplant CTX shows a slightly higher rate of infectious complications compared with HLA-identical ones. Subdistribution of etiologies is similar, with the highest prevalence of viral infections between +30 and +100 and no fungal events after +180. Thus, in haplo-SCT, immunological recovery appears to be satisfactory after +180. Future comparisons with other alternative stem cell sources (i.e. cord blood) are warranted. Disclosures: No relevant conflicts of interest to declare.

Sequential Therapy Combining Clofarabine and HLA-Haploidentical Hematopoietic Stem Cell Transplantation In The Treatment Of Refractory and Advanced Lymphoma: Feasibility, Toxicity and Early Outcome

Allogeneic hematopoietic stem cell transplantation (HSCT) is a valuable treatment option for patients with relapsed or refractory lymphoma including patients with relapse after a first autologous HSCT. However, outcome in non-remission patients is still poor. Here we report the feasibility and efficacy of a protocol using the concept of sequential therapy with clofarabine induction chemotherapy followed by a HLA-haploidentical HSCT in the treatment of patients with advanced non-remission lymphoma. 16 adults (11 male, median age: 53 years, median comorbidity index: 3) with MCL (n=7), CLL (n=1), AITL (n=2), secondary DLBCL (n=2), DLBCL (n=2), follicular lymphoma (n=1), B- lymphoblastic lymphoma (n=1) were treated between September 2010 and February 2013. After induction-chemotherapy with clofarabine (5x30 mg/m² IV), followed by 3 days of rest, a reduced intensity conditioning (RIC) consisting of fludarabine/cyclophosphamide plus melphalan 110 mg/m2 IV was performed prior to a T-cell replete HLA-haploidentical HSCT. High dose cyclophosphamide (Cy) was administered for post-grafting immuno-suppression followed by mycophenolate mofetil and tacrolimus. The median number of immuno-chemotherapy attempts prior to haploidentical HSCT was 4 including 8 autologous HSCT. None of the patients were in complete remission (CR) prior to haploidentical HSCT. After salvage therapy and prior to haploidentical HSCT, progressive disease (PD) was documented in 9 patients with one patient being primarily refractory, while in 7 patients a partial remission (PR) was observed. Neutrophil engraftment was achieved in 16 patients (100%) within a median of 21 days (range 14-36) and platelet engraftment in 14 patients (88%) within a median of 30 days (range 18-115). No primary graft rejection occured. By day +30 CR was achieved in 4 patients (25%) and PR in 11 patients (69%), whereas 1 patient (6%) showed PD. Full donor chimerism on day +30 was detected in all 16 patients. By day +100, 8 of the 14 evaluated 14 patients (57%) achieved CR, 4 (29%) PR, and only 2 (14%) had relapsed. Full donor chimerism was detected in 13 (93%) patients. The rate of acute GvHD grade II-IV was 31%, while chronic GvHD occurred in 3 of 14 (21%) evaluable patients (21%). Non hematologic regimen-related grade III-IV toxicity was observed in 9 patients (56%), and included most commonly transient elevation of liver enzymes (38%), mucositis (19%), and nausea and vomiting (19%). Creatinine elevation (6%), hand-foot syndrome (6%) and haemorrhagic cystitis (6%) were rare. After a median follow up of 14.5 months (range 5.7-35) 4 patients had relapsed, and 4 patients had died, while death was lymphoma-associated only in one patient. Causes of non-relapse mortality (NRM) were haemorrhagic cerebral bleeding in one patient (day +101), and toxicity/infection in 2 patients (day +141; day +156). Cumulative incidence of NRM was 0% on day +100 and increased up to 20% (7-50) on day +360. Estimated one-year overall survival and progression-free survival were 75% (95 CI 46-90) and 56% (95 CI 30-76), respectively. Sequential therapy combining cloforabine induction-chemotherapy and HLA-haploidentical HSCT using RIC, a T-cell replete graft and high dose Cy post-transplant is feasible, shows a favourable toxicity profile and furthermore achieves significant anti-lymphoid activity in patients with advanced non-remission lymphoma. These early results are promising, but longer follow up is needed. Disclosures: Off Label Use: Clofarabine off label use in adults. Hausmann:Sanofi: Travel support Other. Tischer:Sanofi: Travel support Other.

The Use Of Donor Lymphocyte Infusion (DLI) For Relapse After Related T-Cell Replete HLA-Haploidentical Bone Marrow Transplantation (haploBMT) With Posttransplantation Cyclophosphamide (PTCy)

Background HaploBMT with PTCy has now been shown by multiple groups to produce results similar to that seen with matched sibling allogeneic BMT. The use of donor lymphocyte infusion (haploDLI) to treat relapse after haploBMT is not well documented due to theoretical concerns of inducing severe graft-versus-host-disease (GvHD). Here we report our experience of using DLI for relapse after haploBMT. Methods We identified all haploBMT recipients at Johns Hopkins University who received haploDLI for relapse between 6/2003 and 10/2012. Responses were evaluated by standard disease-specific criteria. GvHD was scored using the Keystone and Seattle criteria for acute (a) and chronic (c) GvHD. Duration of survival and response were calculated from date of first haploDLI administration. Patients (pts) were followed till 12/2012. Results Forty pts received 52 haploDLI doses for relapse after haploBMT (16 acute myeloid leukemia [AML], 3 acute lymphoid leukemia [ALL], 5 Hodgkin lymphoma [HL], 7 non-Hodgkin Lymphoma [NHL], 1 myelodysplastic syndrome [MDS], and 9 others). All pts received PTCy, tacrolimus and mycophenolate mofetil for GvHD prophylaxis after haploBMT. Median time from haploBMT to relapse was 183 days; 7 relapses diagnosed within 3 months (M) of haploBMT, 25 relapses within 1 year (yr). Chemotherapy was preadministered to 33 haploDLI doses in 28 pts. 35 pts received haploDLI for florid hematologic relapse, 4 for new minimal residual disease (MRD) relapse detected by cytogenetics or flow cytometry, and 1 for progressive loss of donor chimerism concerning for relapse. Median age at haploDLI administration was 48 yrs (3-70 yrs). No GvHD prophylaxis was administered after haploDLI. The first haploDLI dose received was 1X10^5 CD3+/kg of recipient ideal weight (IBW) in 5 pts, 1-5x10^6 in 31, and 1x10^7 in 4. Thirty-two pts received 1 dose of haploDLI while 8 pts received escalating doses of DLI. Median follow-up was 7M (0.5–98M). Ten pts (25%) developed aGvHD (6 pts had grade 3-4 and 8 pts had grade 2-4). Of 8 pts with grade 2-4 aGvHD, 5 pts received a dose of 1x10^6 and 2 pts received 1x10^7 CD3+/kg dose. 2 pts with GvHD (both grade 3) died within 6 weeks of DLI from sepsis. 3 pts developed cGvHD (2 extensive, 1 limited). Twelve pts responded to haploDLI (30%), all with complete responses (CR), with a median response of 13 M (1.5-96 M). 5 pts had AML, 1 ALL, 1 MDS, 1 HL, 3 NHL, and 1 prolymphocytic leukemia. 10 responders received haploDLI within 4 M of relapse. 10 responders received only 1 haploDLI. 9 pts responded to haploDLI dose of 1-5x10^6 CD3+/kg. 11 had pre-haploDLI chemotherapy or radiation. 3 of the 4 pts treated for MRD relapse responded (75%), while 9 of the 35 treated for florid hematologic relapse responded (26%). Eight CR occurred following the 30 haploDLI doses of 1x10^6 CD3+/kg (26.7%). The CR rate following haploDLI among AML pts was 31.3%. At end of follow-up, 8 of the 12 responders were still alive and in CR, including 5 pts beyond 1-yr post DLI. Five responders developed clinically significant GvHD post haploDLI (3 grade 2-4 aGvHD, 2 extensive cGvHD). Conclusions In our experience in a relatively small number of pts, haploDLI administration for relapse following T-cell replete haploBMT with PTCy is feasible, not associated with unacceptable toxicities, and can result in lasting favorable outcomes. HaploDLI dose of 1x10^6 CD3+/kg of recipient’s IBW appears to be a reasonable starting dose in this setting. Similar to DLI use in the HLA-matched setting, use of haploDLI for MRD relapse seems to result in better outcomes. The CR rate after haploDLI in AML was 31% (5 of 16 pts), similar to what is reported for DLI use in the HLA-matched setting. Small numbers preclude conclusions about disease-specific efficacy of haploDLI in other diseases. Prospective evaluation is required to confirm these findings. Disclosures: Off Label Use: entinostat for MDS. Luznik:Otsuka Pharmaceutical: Research Funding.

Case Report: Haploidentical Stem Cell Transplantation In a 78 Year-Old Patient

An older chronologic age has been a consistent predictor of poor outcomes in hematopoietic stem cell transplantation (HSCT), mainly due to non-relapse mortality (NRM). Therefore, non-curative treatment strategies are commonly adopted for these patients. However, mortality and treatment toxicity has decreased as a result of improved supportive measures, such as reduced intensity conditioning regimens and optimized infection management. T-cell replete haploidentical HSCT emerged as a feasible alternative for leukemia patients without substantial differences in outcomes when compared to fully matched related donor. We report an old adult woman treated with haploidentical HSCT.A 78 year-old female patient presented with anemia, leukocytosis, thrombocytopenia and blasts in the peripheral blood. Diagnosis of acute myelogenous leukemia was established. Conventional cytogenetic demonstrated chromosome eight trisomy, and FISH was negative for other common MDS/AML cytogenetic abnormalities. FLT3-ITD and NPM1 mutations were negative. Her medical history was negative except for heavy smoking. Considering the patients advanced age, the first attending physician chose not to administer intensive treatment and started on decitabine 20 mg/m2 for 5 days. She was refractory to the first-line treatment with persistent cytopenias and blasts in the peripheral blood four weeks after treatment was started. Comprehensive geriatric assessment was performed. She was considered independent for Basic Activities of Daily Living (ADL score 6) and Instrumental Activities of Daily Living (IADL score 27), without cognitive impairment in mini-mental state examination (MMSE score 30), at risk of malnutrition in mini nutritional assessment (MNA 9). As she was considered fit, we decided to perform high-dose chemotherapy with idarubicin and cytarabine, but, once more, the disease was refractory. A rescue regimen was attempted with high-dose cytarabine and mitoxantrone, again, with no response. After discussing pros and cons with the patient and the family, we decided to start Another regimen consisting of topotecan and high dose cytarabine immediately followed by allogeneic hematopoietic stem cell transplantation (HSCT). At day 14, she had 3% blasts in the BM aspirate a T-cell replete haploidentical HSCT using her 52 year-old son as donor and mobilized peripheral blood as stem cell source was performed. Conditioning regimen consisted of fludarabine, cyclophosphamide, TBI 2Gy and post-transplant cyclophosphamide. Graft versus host disease (GVHD) prophylaxis consisted of mycophenolate mofetil and cyclosporine. She had neutrophil engraftment with complete donor chimerism at day+15 and platelet engraftment at day+17. At day+48, she had mild (stage II) skin acute GVHD resolved with topical steroids. Cyclosporine was withdrawn at day+ 93. Due to high relapse risk, the patient was started on monthly post-transplant azacitidine 36 mg/m2. At day+100 the patient remained in complete remission, complete donor chimerism in peripheral blood and bone marrow. Functionality was preserved (ADL score 6 and IADL score 24), presented discrete cognitive impairment (MMSE 28) and malnoutrition (MNA 5). She is now at day+182, doing well and performing again all usual daily activities.To the best of our knowledge, this is the oldest patient treated with haploidentical HSCT. Post transplant cyclophosphamide as T cell depletion strategy in haploidentical HSCT is well tolerated and widely available, being therefore an excellent alternative for patients without conventional donors who require immediate transplant. Older adults with hematologic malignancies are a heterogeneous group and decisions based on chronological age alone are clearly inappropriate. Recently, geriatric assessment proved to be an important prognostic tool in acute leukemia and may be useful in HSCT. In experienced centers, haploidentical HSCT in older adults may be a safe procedure and more accurate pre-transplantation risk stratification tools should be developed. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

In Allogeneic Transplant Recipients Th17 Cells Originate From Donor Stem Cells and Reside In Target Organs of Chronic Graft-Versus-Host Disease

Graft-vs-host disease (GVHD) remains a major complication of allogeneic hematopoietic cell transplantation (HCT). Acute GVHD results from activated donor T cells that infiltrate and damage target organs, producing an inflammatory state. In contrast, the pathophysiology of chronic graft-vs-host disease (cGVHD) remains poorly understood. cGVHD can follow acute GVHD or emerge de novo (>d+100). The clinical picture varies and manifestations can resemble autoimmune disorders. Because IL-17 has emerged as a principal cytokine involved in autoimmunity, Th17 cells have attracted much attention in the transplant community. While IFNg-producing Th1 cells appear to drive acute GVHD, the role of Th17 cells in the pathophysiology of GVHD has not been fully clarified.Here, we used an established minor-antigen disparate mouse model of acute and chronic GVHD to examine the emergence of IL-17+CD4+ Th17 cells post-HCT. Lethally irradiated BALB.B mice received pure hematopoietic stem cells (HSC; cKIT+Thy1.1loSca1+Lin-) or HSC plus splenic T cells from C57BL/6 donors (HSC: GFP; TC: CD45.1+). At several time points lymphoid and GVHD target organs were analyzed for donor T cell infiltration and T cell IL-17 expression. In this model recipients of HSC + T cells developed acute GVHD with intestinal involvement (diarrhea, weight loss) and a mortality of ∼30%, while mice given pure HSC remained healthy. Survivors stabilized around d45, but developed clinically evident chronic GVHD after 6-12 mo manifested by sclerodermatous skin excoriations and liver fibrosis/cirrhosis. Donor T cell infiltration of tissues (spleen, lymph nodes (LN), liver, intestines) was high at 2 and 4 wks post-HCT, but there was no detectable IL-17 production by CD4 cells during acute GVHD. The degree of donor T cell infiltration decreased (as acute GVHD improved) in these tissues. However, at 2 mo post-HCT higher percentages CD4+IL-17+ cells were observed, first in intestines and mesenteric LN, followed by liver and skin. At all time points post-HCT proportions of Th17 cells were higher in HCT recipients (of HSC +/- T cells) as compared to normal wild-type (WT) tissues. To summarize, our key findings are: (i) In our model acute GVHD was driven by adoptively transferred mature (CD4+) T cells that acquired a Th1 phenotype, whereas IL-17 producing donor cells were not detectable during this period. IFNg and T-bet are negative regulators of RORgT, the master regulator of Th17. Thus, this observation is consistent with the idea that in the presence of donor Th1 cells the development of Th17 cells is suppressed. (ii) The effect of Th1-related suppression of Th17 persisted beyond the acute phase: recipients of T-cell replete grafts that survived acute GVHD but later developed chronic GVHD did not demonstrate increased CD4+IL-17+ cells. In these mice, organ-infiltrating donor T cells were primarily adoptively transferred T cells, supporting the postulation that no plasticity exists between committed Th1 and Th17 cells. (iii) Signs of chronic GVHD were observed in animals that had not suffered from severe acute GVHD. In particular, in groups without acute GVHD we observed CD4+IL-17+ cells starting at 2 mo, peaking around 6 mo and which stabilized >1 yr post-HCT. In spleen and peripheral LN of these mice only low levels of CD4+IL-17+ cells were detectable, but their proportion was high in GVHD target organs (liver, intestines, skin). The susceptibility of organs appeared to change post-HCT with high proportions of CD4+IL-17+ cells in the intestines at 2 mo post-HCT that decreased over time. In contrast, CD4+IL-17+ cells in the liver increased later in the time course (Figures). (iv) A centrally important observation was that CD4+IL-17+ cells primarily originated from donor HSC, even in recipients of mature donor T cells. Likewise, recipients of pure HSC showed increasing proportions of Th17 cells over time, and could also manifest signs of cGVHD.From our model we conclude that IL-17 does not contribute to acute inflammatory GVHD. However, IL-17 can be involved in an alternative pathophysiologic mode of chronic GVHD development in the absence of acute inflammation. Since CD4+IL-17+ cells derive from donor HSC and undergo maturation in the host this form of GVHD is delayed, and the emergence and activity of these cells appears to constitute a true autoimmune phenomenon. Our novel hypothesis may explain parts of the complex and obscure pathophysiology of chronic GVHD. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Impact Of Female Donor On Allogeneic Stem Cell Transplantation Outcome Of Male Recipient After T-Cell Depletion By Rabbit Antithymocyte Globulin

The female donor/male recipient combination (FM) increases the risks of graft-versus-host disease (GVHD) and non-relapse mortality (NRM) after allogeneic stem cell transplantation (allo-SCT), with a possible deleterious impact on overall survival (OS) [Gahrton G. Best Pract Res Clin Haematol. 2007 Jun;20(2):219-29]. Most patients in these studies received T-cell replete transplants. As a consequence, and because antithymocyte globulin (ATG) reduces the risk of GVHD, the impact of FM in the specific setting of allo-SCT with ATG remains poorly defined.To explore the impact of FM in the ATG setting, we undertook a retrospective analysis of male adult patients transplanted with rabbit ATG at our center between 01/01/2000 and 12/31/2012. Overall survival and disease-free survival (DFS) were calculated using the Kaplan-Meier estimate, with comparisons by the log-rank test. Cumulative incidences (CI) were used for NRM, relapse (REL), and GVHD in a competing risks setting, NRM being a competing event for REL, and death for GVHD. The Gray test was used to compare CI curves. For multivariate analysis, the variables with p value < 0.1 were entered into a Fine-Gray model where the least significant variables were excluded in sequential fashion until all remaining factors were significant at the p=0.05 level. The following variables were considered: recipient age (≥ vs < 56 years, median age), female donor (FD) vs male donor (MD), matched related (MRD) vs matched unrelated (MUD) donor, peripheral blood (PB) vs bone marrow (BM) graft, GVHD prophylaxis with cyclosporine (CsA)+metho vs others, myeloablative (MAC) vs reduced-intensity conditioning (RIC) regimen, CMV-seropositive vs seronegative recipient, early (CR1 or PR1 or chronic phase or untreated) vs advanced disease. Steroid-refractory (SR) acute (a) GVHD was defined as aGVHD progressing after 3 days of treatment, or unchanged after 7 days, or in incomplete response after 14 days. MUD were matched at the allele level for HLA-A, B, C, DRB1, DQB1.Two hundred and twelve male patients were identified and included in the present study. The median age was 56 years (18-67). Diseases were AML (n=61), ALL (n=16), NHL (n=36), Hodgkin's disease (n=10), myeloma (n=37), MDS (n=26), aplastic anemia (n=7), CLL (n=11), CML (n=1), and MPS (n=7). Status at transplant were CR1 or PR1 or chronic phase (n=74), > CR1 or PR1 (n=83), refractory (n=34), or untreated (n=21). Conditioning regimens were RIC (n=195) or MAC (n=17). Donors were MRD (n=110) or MUD (n=102). Eighty-eight patients were transplanted with a FD. Source of stem cells were PB (n=193), BM (n=18), missing data (n=1). Prophylaxis of GVHD consisted of CsA+metho for 84 patients.The median follow-up was 42 months (5-149). In univariate analysis, the 3-year OS and DFS in FD vs MD groups were 48% ± 6% vs 56% ± 5% (p=0.3) and 42% ± 5% vs 50% ± 5% (p=0.4), respectively. The 3-year NRM and REL in the same groups were 25% ± 5% vs 19.6% ± 4% (p=0.4) and 30% ± 5% vs 31% ± 4% (p=0.9), respectively. The CI of aGVHD II-IV, aGVHD III-IV, SR aGVHD, and extensive chronic GVHD in FD vs MD groups were 37.5% ± 5% vs 33% ± 4% (p=0.5), 22.7% ± 4% vs 17% ± 3% (p=0.3), 17.2% ± 4% vs 8.3% ± 3% (p=0.049), and 20% ± 4% vs 22.5% ± 4% (p=0.9), respectively. Other variables considered in univariate analysis for SR aGVHD were recipient age (p=0.9), recipient CMV status (p=0.7), disease status (p=0.9), RIC vs MAC (p=0.16), MRD vs MUD (p=0.09), PB vs BM graft (p=0.4), and GVHD prophylaxis (p=0.2). In multivariate analysis, the risk factors for SR aGVHD were FD (HR=3.1, 95%CI: 1.2-7.9, p=0.01) and MUD (HR=2.9, 95%CI: 1.1-7.1, p=0.02). The CI of SR aGVHD were 32.3% ± 9.7% in the FD + MUD group (n=29), 9.7% ± 3.8% in the MD + MUD group (n=73), 10.7% ± 4.1% in the FD + MRD group (n=59), and 6.5% ± 3.7% in the MD + MRD group (n=51); p=0.004.We conclude that FD was an independent risk factor for SR aGVHD after allo-SCT with rabbit ATG in male adult patients mostly transplanted with PB after RIC. There was no impact of FD on aGVHD II-IV or III-IV, chronic GVHD, NRM, REL or survival. Finally, the absence of impact of FD on NRM and survival should be interpreted with caution given the retrospective design of the study and because we cannot exclude a possible limiting effect of an insufficient number of patients. Disclosures:No relevant conflicts of interest to declare.

Post-Transplantation Cyclophosphamide (PT-CY) After Myeloablative Conditioning Regimen (MAC) In Unmanipulated Haploidentical Bone Marrow Transplantation (hBMT) Is Highly Effective As Gvhd Prophylaxis and Disease Free Survival In Pediatric and Adult Patients With High Risk Leukemia

Introduction BMT from HLA haploidentical family members (hBMT), using either T-cell depleted or T-cell replete grafts, is increasingly employed in patients who urgently need (but lack) a donor. After the promising results in hBMT obtained by the Baltimore group (Luznik et al., Biol Blood Marrow Transplant 2008, Blood 2010) introducing post-transplant high-dose cyclophosphamide (PT-CY) following a non-myeloablative conditioning regimen, the Genoa group (Raiola et al., Biol Blood Marrow Transplant 2013) has shown, in the haploidentical setting that a myeloablative conditioning (MAC) with PT-CY (on day +3 and +5), cyclosporine from day zero and mycophenolate mofetil (MMF) from day +1, is associated with a high rate of engraftment, acceptable TRM and GVHD, and induces durable remission with low incidence of relapse in a high proportion of patients with high-risk hematologic malignancies. We now report a series of 13 heavly pretreated high-risk leukemia patients who underwent a MAC protocol consisted of TBF regimen: Thiotepa (10 mg/kg), Busulfan (9,6 mg/kg) and Fludarabine (150 mg/mq). As graft versus host disease (GVHD) prophylaxis, 2 patients received a 5 drugs combination (ATG-Fresenius, CSA, MTX, MMF and Basiliximab) and stem cells source was G-CSF-primed haploidentical bone marrow (hBM) cells (Di Bartolomeo et al., Blood 2013). In 11 patients stem cells source was non-primed unmanipulated hBM cells, and GVHD prophylaxis consisted of PT-CY (50mg/kg) iv on day +3 and +4, CSA 2.5 mg/kg/day and MMF 45 mg/kg/day from day +4. Results From 2008 to 2013, 11 adult patients (M/F=8/3; median age 40 years, range 23 to 62) and 2 pediatric patients (M/F=1/1, age 4 and 7 years) with high risk ALL (1 pediatric; 2 adult), AML (1 pediatric; 8 adults) and one Richter evolution of CLL, underwent T replete hBMT. At time of transplant 10 patients were in CR (CR1=9, CR2=1), 1 in a good PR and 2 had refractory disease. Grafts contained a median of 5.68 x 108/kg nucleated BM cells (range 0.7-62.1), 2.14x106/kg CD34+ cells (range 0.55-7.09) and 34.7x106/kg CD3+ cells (range 16-93.4). 12 patients are evaluable for engraftment. This occurred in 100% for neutrophils and 93% for platelets, with a median time to neutrophil recovery (&gt; 0.5 x 109/L) of 22.5 days (range, 13-40) and to platelet recovery (&gt; 20.0 x 109/L) of 27.5 days (range, 17-49). All patients had full donor chimerism by day +30. Non relapse mortality (NRM) was 23%: 2 pt died for sepsis (one before engraftment), 1 for aGVHD. 4 patients had grade I and 3 grade II aGvHD, respectively. Only one patient had a grade III, and another had grade IV fatal GVHD. 3 patients had only limited chronic GvHD. Up to now, only 3 patients have relapsed and of these 2 have died. 8 patients (61.5%) are currently surviving, 7 of them are disease-free with median follow-up time of 165 days (range 32-896 days) from transplant. Conclusion Our preliminary results confirm that haplo-BMT following a MAC regimen, is a feasible treatment in pediatric and adult patients, and that PT-CY is highly effective as GVHD prophylaxis, producing a high rate of stable engraftment with encouraging non relapse mortality and relapse-free survival. Disclosures: No relevant conflicts of interest to declare.

T-Cell–Replete HLA-Haploidentical Hematopoietic Transplantation for Hematologic Malignancies Using Post-Transplantation Cyclophosphamide Results in Outcomes Equivalent to Those of Contemporaneous HLA-Matched Related and Unrelated Donor Transplantation

T-cell-replete grafts from haploidentical donors using post-transplantation cyclophosphamide may represent a solution for patients who require allogeneic hematopoietic cell transplantation (alloHCT) but lack a conventional donor. We compared outcomes of alloHCT using haploidentical donors with those of transplantation using conventional HLA-matched sibling donors (MRDs) and HLA-matched unrelated donors (MUDs). Outcomes of 271 consecutive patients undergoing T-cell-replete first alloHCT for hematologic malignancies performed contemporaneously at a single center (53 using haploidentical donors; 117, MRDs; 101, MUDs) were compared. Overall and disease-free survival (DFS) were adjusted for effects of significant patient-, disease-, and transplantation-related covariates using a stratified Cox model. Patient characteristics were similar between the three donor groups. For patients undergoing MRD, MUD, and haploidentical transplantation, 24-month cumulative incidences of nonrelapse mortality were 13%, 16%, and 7% and of relapse were 34%, 34%, and 33%, respectively (P not significant [NS]). Cumulative incidences of grades 3 to 4 acute graft-versus-host disease (GVHD) at 6 months were 8%, 11%, and 11%, respectively (P NS); extensive chronic GVHD occurred in 54%, 54%, and 38% of patients, respectively (P < .05 for those undergoing haploidentical donor v MRD or MUD transplantation). Adjusted 24-month probabilities of survival were 76%, 67%, and 64% and of DFS were 53%, 52%, and 60%, respectively; these were not significantly different among the three donor groups. Haploidentical transplantation performed using T-cell-replete grafts and post-transplantation cyclophosphamide achieves outcomes equivalent to those of contemporaneous transplantation performed using MRDs and MUDs. Such transplantation represents a valid alternative for patients who lack a conventional donor.

Effect of Graft Source and Transplant Conditioning Regimen Intensity On the Outcomes of Allogeneic Hematopoietic Cell Transplantation for Refractory Mantle Cell Lymphoma (MCL): A Cibmtr Analysis

AbstractAbstract ▪815▪This icon denotes a clinically relevant abstract Introduction:MCL is incurable with conventional chemotherapies and generally follows an aggressive clinical course. After first relapse, the prognosis of refractory MCL is poor with a median survival of approximately 1–2 years. The role of allogeneic hematopoietic cell transplantation (allo-HCT) and the optimal intensity of conditioning regimen for chemotherapy refractory MCL is not known. Methods:We report here the outcomes of allo-HCT in patients with chemorefractory MCL, according to the intensity of transplant conditioning regimens, using the CIBMTR database. The study population included all patients with chemorefractory MCL receiving an allo-HCT reported to the CIBMTR between 1998 and 2010. Patients with evidence of chemosensitive disease at the time of allo-HCT were excluded. Primary outcomes were non-relapse mortality (NRM), progression/relapse (P/R), progression-free survival (PFS), and overall survival (OS). The outcomes of patients undergoing myeloablative conditioning (MA) were compared with those of patients receiving reduced intensity/non-myeloablative conditioning (RIC/NST). Conditioning regimen intensity was defined according to CIBMTR criteria. Results:A total of 74 patients received MA, and 128 underwent RIC/NST. Median follow up of survivors for MA and RIC/NST groups was 35mos and 43mos, respectively. Completeness of follow up at 3 years was 80%. The RIC/NST cohort was older compared with MA cohort (median age 59 yrs vs. 54 yrs, respectively; p<0.001). No significant differences at baseline were observed between the MA and RIC/NST groups in terms of disease stage at diagnosis, B-symptoms, bone marrow or extranodal involvement, disease bulk, central nervous system involvement, disease status at transplantation (primary refractory disease vs. refractory at relapse) and graft type (bone marrow vs. peripheral blood). Significantly more patients in the RIC/NST group had a prior history of undergoing an autologous-HCT (33% vs. 13%; p=0.004), received rituximab therapy prior to transplantation (41% vs. 15%; p0.01) and underwent unrelated donor (URD) allo-HCT (68% vs. 32%; p<0.001) (Table 1). Patients in the RIC/NST group were also more heavily pretreated (p=0.02). Cumulative incidence of grade II-IV acute GVHD at day +100 was 36% and 37% in MA and RIC/NST groups (p=0.93), respectively. Cumulative incidence of chronic GVHD at 1 year post transplantation in similar order was 35% and 43%, respectively (p=0.35). On univariate analysis, at 3 years, comparing MA allo-HCT with RIC/NST allo-HCT no significant differences were found in terms of NRM (47% vs. 43%; p=0.68), R/P (33% vs. 32%; p=0.89), PFS (20% vs. 25%; p=0.53), and OS (25% vs. 30%; p=0.45), respectively. On multivariate analysis, receiving a bone marrow allograft (compared to a peripheral blood graft) and GVHD prophylactic strategies consisting of ex-vivo T-cell depletion or CD34+ selection (compared to tacrolimus-based GVHD prophylaxis) were associated with an increased risk of NRM and inferior PFS and OS. On multivariate analysis higher intensity conditioning was not associated with reduced risk of NRM, R/P or better PFS and OS. Conclusions:Despite a refractory disease state, a small subset of chemotherapy refractory MCL patients can attain durable remissions after allo-HCT. T-cell replete, peripheral blood products appear to be the optimal graft source in refractory MCL patients undergoing allo-HCT. Compared to a more heavily pretreated RIC/NST cohort, MA allo-HCT in refractory MCL patients, was not associated with a reduced risk of relapse or improved survival.Table 1Baseline Patient Characteristics.Myeloablative N=74 (%)RIC/NST N=128 (%)P-valueMedian Age (range)54 (27-69)59 (42-75)<0.001Male sex63 (85)99 (77)0.81KPS ≥9023 (31)56 (44)0.26No prior auto-HCT64 (86)86 (67)0.004Interval from diagnosis to transplant, months15 (4-184)29 (5-135)0.001Disease status37 (50)57 (45)0.45Primary-refractory37 (50)71 (55)Resistant relapseGraft type13 (18)20 (16)0.72Bone marrow61 (82)108 (84)Peripheral bloodHLA-identical sibling47 (64)37 (29)<0.001 Disclosures:No relevant conflicts of interest to declare.

Influence of Graft Versus-Host Disease Prophylaxis Regimen On T-Cell Repertoire Diversity Following Reduced-Intensity HLA-Matched Unrelated Donor Allogeneic Hematopoietic Stem Cell Transplantation.

AbstractAbstract 3054 Background:A clearly superior graft-versus-host disease (GVHD) prophylaxis regimen has not been established for patients undergoing reduced intensity allogeneic hematopoetic stem cell transplantation (HSCT) from matched unrelated donors (URD). Encouraging results have been reported with both the combination of alemtuzumab and cyclosporine (AC) and the regimen of tacrolimus, methotrexate, and sirolimus (TMS) in the URD setting. These two regimens work by biologically distinct mechanisms and may have markedly different effects on immune reconstitution. T-cell receptor (TCR) spectratyping analysis, which provides information on antigen receptor diversity, is a valuable method for monitoring post-transplant immune reconstitution. As part of a randomized pilot study, we prospectively assessed the effects of AC vs. TMS on TCR Vb repertoire diversity in patients undergoing reduced intensity HLA-matched unrelated donor transplantation. Methods:Twenty patients (median age 53 yrs; range 24–70 yrs) with hematologic malignancies received reduced intensity conditioning (fludarabine 30 mg/m2/day and cyclophosphamide 1200 mg/m2/day IV Day -6 to -3) followed by a 10/10 HLA-matched unrelated donor T-cell replete mobilized peripheral blood allograft. Patients were randomized to receive either: AC (n=10): alemtuzumab 20 mg/day IV over 8 hours Days -8 to -4 and cyclosporine starting at Day -1 with a 10% per week taper starting at Day +100 or TMS (n=10): tacrolimus and sirolimus starting at Day -3 with a 33% taper at Day +63 and Day +119 and methotrexate 5 mg/m2 IV, Days +1, +3, +6, and +11. Blood samples were collected from the donor and patient at baseline and the patient at 1, 3, 6 and 12 months post-transplant for TCR spectratyping analysis. All comparisons are based on an exact Wilcoxon rank sum test; p values < 0.01 were significant because of multiple comparisons. Results:Patients on the AC arm had significantly fewer T-cells on Day +14 compared with the TMS arm (median CD3+ = 1 cells/μl vs 356 cells/μl; CD4+ = 0 cells/μl vs 243 cells/μl; CD8+ = 0 cells/μl vs. 59 cells/μl; each p<0.0001); there was less disparity at Day +28 (median CD3+ = 45 cells/μl vs. 398 cells/μl; CD4+ = 36 cells/μl vs. 218 cells/μl; CD8+= 5 cells/μl vs 152 cells/μl; each p 0.002). By Day +100, lymphocyte recovery was not appreciably different between the two arms (median CD3+ = 242 cells/μl vs. 445 cells/μl (p = 0.095): CD4+ = 106 cells/μl vs. 212 cells/μl (p=0.28); CD8+ = 72 cells/μl vs. 135 cells/μl (p = 0.03). NK-cell recovery was slightly less in the AC vs. TMS arm at Day +14 (median NK = 27 cells/μl vs. 70 cells/μl; p = 0.01) and at Day +28 (median NK = 29 cells/μl vs. 150 cells/μl; p=0.02). There was no difference by Day +100 (median NK = 124 cells/μl vs. 88 cells/μl; p=0.31). B-cell reconstitution was negligible in both arms through Day +100. Assessment of CD4+ TCR Vb repertoire diversity by spectratyping demonstrated significantly lower diversity in patients receiving AC at 1 (p = 0.0003), 3 (p = 0.0003) and 6 (p=0.003) months post transplant compared with patients receiving TMS. CD8+ TCR spectratyping similarly revealed significantly reduced diversity in the AC arm at 3 (p = 0.001) and at 6 months (p = 0.003), and a trend toward significance at 12 months (p = 0.07). On each of the 2 arms, 2 of 10 patients developed acute Grade II-IV GVHD. Of the 5 patients on the AC arm who were seropositive for CMV, all 5 reactivated CMV by PCR within the first 60 days and reactivated 2–5 times in the first year. In contrast, only 3 of 5 seropositive patients reactivated CMV on the TMS arm and only one reactivated in the first 60 days. Conclusions:Two factors may have contributed to the loss of repertoire diversity in the AC arm. First, the alemtuzumab regimen may have severely depleted the infused donor T-cells. Second, stimulation by reactivating virus may have induced expansion of CMV-specific memory and effector T-cells, resulting in a skewed and oligoclonal T-cell repertoire. Especially in CD8+ T-cells, CMV has been shown to produce significant oligoclonal expansion (including CD4+: CD8+ ratio inversion). The loss of T-cell numbers and repertoire may in turn have contributed to the prevalence of early CMV reactivation. Thus, despite the similarities in frequency of acute GVHD in this small sample, it appears that these two commonly used GVHD prophylaxis regimens have very different effects on post-transplant immune reconstitution in the first 6 months after allogeneic HSCT. Disclosures:No relevant conflicts of interest to declare.

Mycophenolate Mofetil versus Methotrexate for Prevention of Acute Graft-Versus-Host Disease: Results of a Systematic Review Limited to Prosepective Randomized Controlled Studies

Abstract 4168 Background:Morbidity and mortality due to acute and subsequently chronic graft-versus-host disease (GVHD) remains a serious limitation to wider applicability of T-cell replete allogeneic HCT for otherwise incurable hematologic diseases. Developing active regimens for acute GVHD (aGVHD) prophylaxis is necessary due to current absence of effective treatments for severe aGVHD, particularly if refractory to corticosteroids. Both mycophenolate mofetil (MMF) and methotrexate (MTX) based regimens have been used clinically to prevent aGVHD. However, conflicting results have been noted when comparing, directly or indirectly, MMF-based against MTX-based regimens for prevention of aGVHD. Methods:A systematic literature search was performed using MEDLINE and Cochrane's CENTRAL databases. All prospective-randomized controlled trials (RCT) comparing MMF-based regimens versus MTX-based regimens for prevention of aGVHD were eligible for inclusion and analysis. Our primary outcomes were overall survival (OS) and incidence of grade II-IV aGVHD. Our secondary outcomes were time-to-neutrophil engraftment, time-to-platelet engraftment, incidence of chronic GVHD (cGVHD), incidence of severe mucositis, frequency of pain control requirement, frequency of total parenteral nutrition (TPN) use, relapse rate, and incidence of non-relapse mortality (NRM). Pooling of data from similar outcomes was done using the random-effects model. Results:Three studies enrolling 174 patients (MMF= 95; MTX= 79) were included in this systematic review. Pooled analysis shows that use of MMF, for aGVHD prophylaxis, results in significantly faster platelet engraftment (pooled hazard ratio (HR)= 0.87 (95%CI, 0.81,0.93; p<0.0001)) reported in 2 studies (129 patients), a lower incidence of severe mucositis (pooled risk ratio (RR)=0.48 (95%CI, 0.33, 0.71; p=0.0002)) reported in 3 studies (174 patients), and less use of TPN (pooled RR=0.48 (95%CI, 0.26, 0.90; p=0.02)) reported in 2 studies (129 patients) or narcotics for pain control (pooled risk ratio=0.76 (95%CI, 0.63, 0.91; p=0.002)) reported in 2 studies (129 patients) compared to MTX. There was no difference, however, between MMF and MTX in OS (pooled HR=0.73 (95%CI, 0.45, 1.17; p=0.19)) reported in 2 studies (129 patients), incidence of grade II-IV aGVHD (pooled RR=1.31 (95%CI, 0.85, 2.03; p=0.22)) reported in 3 studies (174 patients), incidence of cGVHD (pooled RR=0.92 (95%CI, 0.65, 1.30; p=0.62)) reported in 2 studies (129 patients), time to neutrophil engraftment (pooled HR=0.77 (95%CI, 0.51, 1.17; p=0.23)) reported in 2 studies (129 patients), relapse risk (pooled RR=0.84 (95%CI, 0.52,1.38; p=0.50)) reported in 2 studies (129 patients), or NRM (RR=1.21 (95%CI, 0.62, 2.36; p=0.57)) reported in one study (89 patients). Conclusion:Critical appraisal of available published evidence appears limited/weak to recommend one particular agent, MMF or MTX, to combine with a calcineurin inhibitor as the favored aGVHD prophylaxis regimen. A large randomized controlled trial that compares MMF and MTX is required to address this issue. But, identifying the most optimal dose(s) and schedule(s) of administration of MMF and MTX is required in advance. Disclosures:No relevant conflicts of interest to declare.

Pre-Transplant FDG-PET Scan Lacks Prognostic Value in Chemosensitive B-Cell Non-Hodgkin Lymphoma Patients Undergoing Non-Myeloablative Allogeneic Stem Cell Transplantation.

AbstractAbstract 3130▪▪This icon denotes a clinically relevant abstract Background:Allogeneic stem cell transplantation (alloSCT) remains the only curative therapy for patients with indolent B cell non-Hodgkin’s Lymphoma (B-NHL) as well as patients with aggressive B-NHL that have failed prior autologous stem cell transplants (ASCT). Non-myeloablative (NMA) alloSCT has been universally implemented for B-NHL given the extensive prior therapy and advanced age of the typical patient undergoing alloSCT for these diseases and resultant 40–50% incidence of transplant-related mortality (TRM) with myeloablative conditioning per registry series’. NMA alloSCT relies on graft-versus-lymphoma (GVL) effect for disease control. While the literature has suggested improved event-free survival (EFS) for B-NHL patients with a negative fluorine-18-deoxyglucose positron emission tomography (FDG-PET) scan prior to ASCT in chemosensitive patients, this has not been elucidated in a conventional NMA alloSCT treatment platform. Our hypothesis is that FDG avidity pre-NMA alloSCT is not prognostic to progression-free survival (PFS) in chemosensitive patients with B-NHL. Methods:This is a retrospective study of adult B-NHL patients with disease assessed by CT and FDG-PET prior to undergoing a T-cell replete NMA alloSCT from a 9/10 or 10/10 HLA matched related or unrelated donor conditioned with cyclophosphamide 50 mg/kg x1, fludarabine 25 mg/m2 daily over 5 days and 2 Gy total body irradiation, with or without peri-allo-SCT rituximab 375 mg/m2 administered approximately day (d) -8, d+21, d+28, d+25, d+42 as per an internal protocol. Patients receiving an unrelated donor graft received equine anti-thymocyte globulin 30 mg/kg administered daily d-3 and d-2. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus, sirolimus and methotrexate (n=51) or cyclosporin-A and mycophenolate mofetil (n=15). Event-free survival (EFS) was calculated using Kaplan-Meier method. An event is defined as progression of disease (PD) or death from any cause. Results:This analysis includes 66 patients with a median age of 54 (range 33–69) years at the time of allo-SCT. Diagnoses included: 16 CLL/SLL, 30 FL, 11 DLBCL/transformed B-NHL, 6 MCL and 3 other. Patients were previously treated with a median of 3 prior chemotherapy regimens (range 1–6) and 12 patients had undergone a previous ASCT. Fifty-one patients (77%) were chemosensitive at the time of alloSCT by CT criteria, as defined by either a complete or partial remission (Cheson et al, JCO 1999; Hallek et al, Blood 2005 for CLL/SLL). Of these 51 patients, 18 had FDG-avidity on FDG-PET at time of allo-SCT above liver background per Deauville criteria (Meignan et al, Leukemia and Lymphoma 2009). The median hematopoietic comorbidity index (HCT-CI) was 1 (range 0–8). Twenty-six patients received a graft from a 10/10 HLA matched related donor, 34 from a 10/10 HLA matched unrelated donor and 6 from a 9/10 HLA mismatched unrelated donor. Eighty-six percent of the patients received peri-alloSCT rituximab. The median follow-up for survivors is 29 (range 3–67) months. Of the 15 events, 10 were TRM (7 GVHD-related deaths) and 5 PD (3 chemosensitive patients and 2 chemorefractory patients pre-alloSCT). Only 1 event has occurred beyond 13 months. The estimated 2 year EFS is 77%. There was no difference in EFS according to: CR vs PR, graft source, number of previous lines of therapy, GVHD prophylaxis, peri-alloSCT rituximab, previous ASCT, or HCT-CI. The estimated EFS at 2 years for chemosensitive patients per CT criteria is 86% compared to 50% for patients without chemosensitivity pre-allo-HCT (figure 1, p<0.01). FDG-PET (+) was not prognostic in the chemosensitive patients prior to alloSCT (figure 2, p=ns). Only 2 of the 15 non-chemosensitive patients were FDG-PET (−) at time of alloSCT. Both of these patients had CLL/SLL and are event-free at 20 and 35 months post-alloSCT. Conclusions:Chemosensitivity prior to T-cell replete NMA alloSCT for B-NHL predicts outcome post-transplant. FDG-PET scan did not add prognostic value to patients deemed chemosensitive by traditional CT criteria in our dataset. The majority of the events were TRM, which needs to be taken into consideration when interpreting these results. Transplant related mortality, especially GVHD related, continues to greatly impact survival of B-NHL patients undergoing NMA alloSCT. [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Lineage–Specific Chimerism and Incidence of Graft-Failure Following T-Cell Replete Haploidentical Transplantation Using Post-Transplant Cyclophosphamide in Eighty-Nine Consecutive Patients From a Single-Center.

Abstract 3030T-cell replete HLA-haploidentical transplantation using post-transplant cyclophosphamide for prevention of GVHD and graft rejection (Haplo-PTCy) has recently emerged as a valid form of alternative-donor transplantation for patients who lack traditional matched-siblings (MSD) or matched-unrelated donors (MUD). We have demonstrated that patients undergoing Haplo-PTCy can have equivalent rates overall and disease-free survival and equivalent or lower cumulative incidences of GVHD and non-relapse mortality to patients transplanted contemporaneously from MSD and MUD at the same center (Bashey et al ASH 2011 abstract #833). In this study we assessed lineage-specific chimerism, together with incidence and outcome of graft-failure in 89 consecutive first Haplo-PTCy performed for hematologic malignancy in our center between Oct 2005 and Jun 2012. Patient characteristics: M 48, F 41; median age 48 (20–74); Diagnosis AML 28, ALL 16, CLL 11, NHL 9, HL 8, CML 8, MDS 7, MPS 2; median number of matched HLA loci were 5/10 (range 5/10 to 8/10); Median CD34+ and CD3+ cell dose infused were 4.01 × 106/kg (0.84–6.27) and 5.35 × 107/kg (1.4–53.82) respectively. Fifty-eight patients received a marrow graft and 31 received G-CSF mobilized PBSC. The preparative regimen was RIC/NST in 59 (fludarabine 30 mg/m2/d d -6 to -2, TBI 200cGy d-1, cyclophosphamide 14.5 mg/kg/d d-6 & -5, and 50 mg/kg/d d+3 & +4) and myeloablative in 30 (regimen A- fludarabine 30 mg/m2/d d -6 to -2, busulfan 110–130 mg/m2/d d-7 to -4, cyclophosphamide 14.5 mg/kg/d d-3 & -2, and 50 mg/kg/g d+3 & +4 [20 patients] and regimen B- fludarabine 30 mg/m2/d d -7 to -5, TBI 1200 cGy given in 8 fractions between days-4 to -1 and cyclophosphamide 50 mg/kg/d d +3 & +4 [10 patients]). The presence of pre-transplant anti-donor HLA antibodies were assessed using a solid phase assay (Panel Reactive Antibody, PRA, Clinimmune, CO) and by anti-donor cross-matching by flow cytometry (Clinimmune). All donors were selected to provide a negative cross-match using recipient serum and donor T-cells prior to transplant. Engraftment was determined using standard CIBMTR criteria. Lineage-specific chimerism was determined using PCR for short tandem repeats on peripheral blood mononuclear cells separated by CD3 and CD33 expression using immunomagnetic beads on d 30,60,90 and 180 following transplant. Median time to ANC > 500/mm3 was 16d (12–27d) and platelets > 20,000/mm3 was 26d (0–26d). Median T-cell (CD3) and myeloid (CD33) donor chimerisms were 100%, at all time-points assessed from d30–180 (Fig 1). All 30 patients who received a myeloablative Haplo-PTCy had full engraftment of T-cells and myeloid cells starting d +30. However six of 59 patients undergoing RIC/NST Haplo-PTCy had primary failure of T-cell engraftment -median CD3 chimerism (range) for these patients on d 30 and 60 were 0% (0–6%) and 0% (0–14%). Median CD33+ cell chimerism for the same patients on d 30 and 60 respectively were 86% (0–100%) and 45% (0–100%). Four of these patients underwent a second Haplo-PTCy, a median of 105d (range 8–123d) following the first transplant using a different haploidentical donor and the same preparative regimen. In each case the second Haplo-PTCy was successful (CD3+ donor chimerism 100% by d 30–60 in all cases). One patient who was too unwell for second Haplo-PTCy had spontaneous improvement in CD3 chimerism (6–14% d 30–90 improving to 100% d 180) and one patient died of progressive malignancy before a second Haplo-PTCy could be performed.These data demonstrate that full donor chimerism of T-cells and myeloid cells is usual following Haplo-PTCy from the earliest time-points assessed. Engraftment failure was not seen in any patient using the myeloablative regimens described above. Approximately 10% of patients conditioned with the RIC/NST regimen failed to undergo initial T-cell engraftment. However, re-transplantation was successful in all cases when attempted. Late spontaneous improvement of CD3 chimerism is also possible in patients with low level mixed chimerism early post-transplant. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Donor Lymphocyte Infusions (DLI) Following Haplo Bone Marrow Transplantation (hBMT) with High-Dose of Cyclophosphamide Post-Transplant As Gvhd Prophylaxis

AbstractAbstract 1950 Background:In the haploidentical setting, the use of donor lymphocyte infusions (DLI) is associated with a significant risk of acute and chronic graft vs host disease (GvHD): in one report, a median T-cell dose of 2.4 × 10⋀8/kg was administered to recipients of unmanipulated haploidentical stem cell transplants, and a cumulative incidence of chronic GVHD of 50% was reported (Huang X, BBMT 2009). It is possible that patients receiving high dose Cyclophosphamide post-transplant (PT-CY) may be able to receive DLI with a lower risk of GvHD Aim of the study:We tested the feasibility and occurrence of GVHD, following 32 DLI administered in sixteen patients, who relapsed after an unmanipulated haploidentical T-cell replete BMT, and PT-CY. Patients and Methods:All sixteen patients were transplanted from haploidentical related donor, after a myeloablative conditioning (n=10) or a non myeloablative conditioning (n=6) with PT-CY as GVHD prophylaxis, in association with CyA and micophenolate. The diagnosis was Hodgkin’s lymphoma (n 6), acute lymphoblastic B-cell leukemia (n=3), acute myeloid leukemia (n=5), pro-lymphocytic T-cell leukemia (n=1), chronic myeloid leukemia blast crisis (n=1). The median time of relapse was 211 days from transplant (range 45–697 days); the median time at DLI was 48 days from relapse (range 29–540 days) and 252 days from transplant (range 109–690). Ten patients had hematologic relapse, while six had molecular relapse.At time of first DLI all patients were off GVHD prophylaxis.The minimum dose of lymphocytes was 1 × 103′/kg (n=2); higher doses were as follows: 1 × 104′/kg (n=13), 1 × 105′/kg (n=11), 5 × 105′/kg (n=4), 1 × 106′/kg (n=2). The median number of DLI/patient, was 1 (range 1–5). In eleven cases DLI followed chemotherapy: gemcitabine or bendamustine in Hodgkin’s lymphoma and pro-lymphocytic leukemia; fludarabine, ara-C and antracycline containing regimens in acute leukemia. Median time of DLI was 12 days from chemotherapy (range 10–14 days), during the chemotherapy-induced nadir. Five patients received DLI alone. Results:The infusions were well tolerated and no major adverse effect was observed.The cumulative incidence of acute GvHD grade II-III, was 6%, and 0% for chronic GVHD. No aplasia related to haplo-DLI occurred.Five patients died with progressive disease; 11 patients are surviving (69%), 4 of them are disease-free, seven have active disease; two patients relapsed after 313 and 135 days from DLI, respectively. The median follow-up is 221 days (range 46–559 days). Conclusions:This study suggests that patients grafted with haplo-mismatched BMT and high dose post-transplant cyclophosphamide, can be treated with DLI at doses up to 1× 106′/kg, with a very low risk of developing acute or chronic GVHD. Disclosures:No relevant conflicts of interest to declare.

Achieving Graft-Versus-Tumor Effect in Brain Tumor Patients: From Autologous Progenitor Cell Transplant to Active Immunotherapy

Success in treating aggressive brain tumors like glioblastoma multiforme and medulloblastoma remains challenging, in part because these malignancies overcome CNS immune surveillance. New insights into brain tumor immunology have led to a rational development of immunotherapeutic strategies, including cytotoxic Tlymphocyte therapies and dendritic cell vaccines. However, these therapies are most effective when applied in a setting of minimal residual disease, so require prior use of standard cytotoxic therapies or cytoreduction by surgery. Myeloablative chemotherapy with autologous hematopoietic cell transplantation (autoHCT) can offer a platform upon which different cellular therapies can be effectively instituted. Specifically, this approach provides an inherent 'chemical debulking' through high-dose chemotherapy and a graft-versus-tumor effect through an autologous T-cell replete graft. Furthermore, autoHCT may be beneficial in 'resetting' the body's immune system, potentially 'breaking' tumor tolerance, and in providing a 'boost' of immune effector cells (NK cells or cytotoxic T lymphocytes), which could augment desired anti-tumor effects. As literature on the use of autoHCT in brain tumors is scarce, aspects of immunotherapies applied in non-CNS malignancies are reviewed as potential therapies that could be used in conjunction with autoHCT to eradicate brain tumors.