Limited Chronic GVHD Research Articles

Decitabine-Intensified Modified Busulfan/Cyclophosphamide Conditioning Regimen Improves Survival in Acute Myeloid Leukemia Patients Undergoing Related Donor Hematopoietic Stem Cell Transplantation: A Propensity Score Matched Analysis.

To identify the benefit of decitabine (Dec)-intensified myeloablative conditioning on the outcomes of patients with acute myeloid leukemia (AML) after related donor hematopoietic stem cell transplantation (HSCT), we performed a retrospective matched‐pair study from a pool of 156 patients to evaluate Dec [20 mg/m2/day intravenously (i.v.) on days −11 to −7]-intensified modified busulfan/cyclophosphamide (mBuCy) conditioning regimen vs. mBuCy regimen in 92 AML patients, with 46 patients in each cohort. The cumulative incidence of grade II–IV acute graft-versus-host disease (aGVHD) was lower in the Dec group (15.2% ± 0.3% vs. 32.6% ± 0.5%, P = 0.033). Compared with mBuCy group (15.5% ± 0.3%), a significantly higher proportion of limited chronic GVHD (cGVHD) in Dec group (35% ± 0.6%) was observed (P = 0.025). Dec-intensified mBuCy conditioning was associated with better 2-year overall survival (OS) and GVHD-free relapse-free survival (GRFS) (81% ± 6.2% vs. 59.4% ± 7.5%, P = 0.03; 58.7% ± 8.1% vs. 40.9% ± 7.3%, P = 0.042; respectively). Our results also elucidated that the Dec group had better 2-year OS and lower 2-year cumulative incidence of relapse (CIR) in patients acquiring haploidentical HSCT than that of the mBuCy group (84.8% ± 7.1% vs. 58.2% ± 10.3%, P = 0.047; 17.9% ± 0.8% vs. 40.0% ± 1.0%, P = 0.036; respectively), which did not increase the treatment-related mortality and regimen-associated toxicities. Dec-intensified myeloablative regimen and high-risk stratification were the variables associated with OS, leukemia-free survival (LFS), and GRFS in multivariate analysis. In high-risk patients, no differences were found in CIR, OS, LFS, and GRFS between the two groups. These data indicated that Dec-intensified mBuCy conditioning regimen was associated with better survival than mBuCy regimen in AML patients, especially in patients undergoing haploidentical HSCT.

The impact of GVHD on outcomes after adult single cord blood transplantation in European and Japanese populations.

The impact of GVHD and graft-versus-leukemia effect in unrelated cord blood transplantation (UCBT) is controversial. In the Eurocord/ALWP EBMT and JSTCT/JDCHCT collaborative study, we evaluated the impact of GVHD on UCBT outcomes in Japanese and European registries. A total of 3,690 adult patients with acute leukemia who received their first single UCBT were included. A multivariate analysis of overall survival (OS) revealed a positive impact of grade II acute GVHD compared with grade 0-I GVHD, in the Japanese cohort (hazard ratio (HR), 0.81; P = 0.001), and an adverse impact in the European cohort (HR, 1.37; P = 0.007). A negative impact of grade III-IV acute GVHD on OS was observed regardless of registries. In the analysis of relapse, a positive impact of grade II acutes GVHD compared with grade 0-I GVHD was observed only in the Japanese cohort, regardless of disease risk. The positive impact of limited chronic GVHD on OS was observed only in the Japanese cohort. In conclusion, a positive impact of mild GVHD after a single UCBT was observed only in the Japanese cohort. This could explain the ethnic difference in UCBT outcomes and might contribute to the preference usage of UCBT in Japan.

Silver Lining: Reduced Relapse with Chronic GVHD after Transplant for MDS.

Chronic GVHD following hematopoietic cell transplantation is associated with reduced relapse incidence in patients with leukemias. This impact has been investigated in myelodysplastic syndrome, showing a beneficial impact of limited chronic GVHD on transplant outcomes in a cohort of more than 3,000 patients.See related article by Konuma et al., p. 6483.

Augmented immunosuppression and PTCY-based haploidentical hematopoietic stem cell transplantation for thalassemia major.

Alternate donor HSCT for thalassemia major from a matched unrelated donor or haploidentical family donor is a feasible therapeutic option in children with no matched family donor. Aggressive pretransplant immunosuppression, reduced toxicity conditioning, and PTCY result in excellent thalassemia-free survival. We describe here our experience in this cohort. We performed a retrospective analysis of the data on children who underwent a haploidentical HSCT for thalassemia major with PTCY at our center from August 2017 to August 2019. All children received pretransplant immune suppression for 6weeks with fludarabine and dexamethasone, hypertransfusion and chelation with intravenous desferrioxamine. Conditioning included thiotepa, fludarabine, rabbit ATG, and cyclophosphamide, and GvHD prophylaxis included PTCY with tacrolimus. Twenty children were included and nineteen children engrafted. Acute hypertension occurred in five children, bacterial infection in eight children and viral respiratory infection in three children. Three children suffered from graft rejection. Reactivation of viruses namely CMV, adenovirus, and BK virus was seen in 60% of children. Grades 1-2 acute GvHD of the skin in four children (20%) and limited chronic GvHD of the skin in four children (20%). Immune cytopenia was documented in three children (15%). Haploidentical HSCT offers a therapeutic option for children with thalassemia major with no suitably matched family or unrelated donors. Our reduced toxicity regimen with PTCY offers a DFS of 75% and OS of 95% with low transplant-related mortality of 5%.

Targeted busulfan-based reduced-intensity conditioning and HLA-matched HSCT cure hemophagocytic lymphohistiocytosis

AbstractReduced-intensity/reduced-toxicity conditioning and allogeneic T-cell replete hematopoietic stem cell transplantation are curative in patients with hemophagocytic lymphohistiocytosis (HLH). Unstable donor chimerism (DC) and relapses are clinical challenges . We examined the effect of a reduced-intensity conditioning regimen based on targeted busulfan to enhance myeloid DC in HLH. The European Society for Bone and Marrow Transplantation–approved reduced-intensity conditioning protocol comprised targeted submyeloablative IV busulfan, IV fludarabine, and serotherapy comprising IV alemtuzumab (0.5-0.8 mg/kg) for unrelated-donor and IV rabbit anti–T-cell globulin for related-donor transplants. We assessed toxicity, engraftment, graft-versus-host disease (GHVD), DC in blood cell subtypes, and overall survival/event-free survival. Twenty-five patients from 7 centers were treated (median age, 0.68 year). The median total dose and cumulative area under the curve of busulfan was 13.1 mg/kg (6.4-26.4) and 63.1 mg/L × h (48-77), respectively. Bone marrow, peripheral blood stem cell, or cord blood transplants from HLA-matched related (n = 7) or unrelated (n = 18) donors were administered. Donor cells engrafted in all patients (median: neutrophils d+20/platelets d+28). At last follow-up (median, 36 months; range, 8-111 months), the median DC of CD15+ neutrophils, CD3+ T cells, and CD16+56+ natural killer cells was 99.5% (10-100), 97% (30-100), and 97.5% (30-100), respectively. Eight patients (32%) developed sinusoidal obstruction syndrome, resolving after defibrotide treatment. The 3-year overall survival and event-free survival rates were both 100%. None of the patients developed acute grade III to IV GHVD. Limited chronic GVHD was encountered in 4%. This regimen achieves excellent results with stable DC in patients with HLH.

Effect of graft-versus-host disease on outcomes after pediatric single cord blood transplantation.

The effect of GVHD on transplant outcomes after unrelated cord blood transplantation (UCBT) is not yet fully understood. Pediatric patients aged 0-15 years with acute leukemia or myelodysplastic syndrome who underwent their first UCBT (n = 740) were selected from the Japanese registry. Fifty percent of the patients received a UCB unit containing more than 5.0 × 107/kg total nucleated cells. The occurrence of grade III-IV acute GVHD was associated with a higher risk of non-relapse mortality (NRM, hazard ratio [HR] 4.07, P < 0.001) compared with no acute GVHD. Grade I-II acute GVHD was not associated with NRM. The occurrence of grade I-II or grade III-IV acute GVHD was not associated with a relapse risk. These findings showed that grade I-II acute GVHD carried no survival benefit and grade III-IV acute GVHD had an adverse effect (HR 1.68, P = 0.007). The occurrence of limited chronic GVHD was associated with a low risk of overall mortality (HR 0.60, P = 0.045). Severe acute GVHD should be prevented because of its association with high overall mortality and NRM in pediatric single UCBT. Mild acute GVHD provides no overall benefit. Mild chronic GVHD may be beneficial for survival.

Haploidentical transplantation and posttransplant cyclophosphamide for treating aplastic anemia patients: a report from the EBMT Severe Aplastic Anemia Working Party.

In the absence of an HLA-matched donor, the best treatment for acquired aplastic anemia patients refractory to immunosuppression is unclear. We collected and analyzed data from all acquired aplastic anemia patients who underwent a haploidentical transplantation with posttransplant cyclophosphamide in Europe from 2011 to 2017 (n = 33). The cumulative incidence of neutrophil engraftment was 67% (CI95%: 51-83%) at D +28 and was unaffected by age group, stem cell source, ATG use, or Baltimore conditioning regimen. The cumulative incidence of grades II-III acute GvHD was 23% at D +100, and limited chronic GvHD was 10% (0-20) at 2 years, without cases of grade IV acute or extensive chronic GvHD. Two-year overall survival was 78% (64-93), and 2-year graft-versus-host disease-free survival was 63% (46-81). In univariate analysis, the 2-year OS was higher among patients who received the Baltimore conditioning regimen (93% (81-100) versus 64% (41-87), p = 0.03), whereas age group, stem cell source, and ATG use had no effect. Our results using unmanipulated haploidentical transplantation and posttransplant cyclophosphamide for treating refractory AA patients are encouraging, but warrant confirmation in a prospective study with a larger number of patients and longer follow-up.

An Update of Australasian Trends in Allogeneic Stem Cell Transplantation for Myelofibrosis in the Molecular Era

An Update of Australasian Trends in Allogeneic Stem Cell Transplantation for Myelofibrosis in the Molecular Era

Excellent outcomes of combined umbilical cord blood and bone marrow grafts for allogeneic transplantation of pediatric patients from HLA-matched siblings. a single institution experience.

Background & Aim We hypothesized that combining cord blood (CB) and bone marrow (BM) grafts from HLA-identical siblings would improve the outcome of allogeneic transplantation in pediatric patients: the increased number of infused BM progenitor cells would expedite engraftment and the CB naive T cells would lower the risk of GvHD. Methods, Results & Conclusion Methods We reviewed the data of consecutive patients who received combined CB and BM grafts at our institution (MSKCC). Outcomes of interest were patient neutrophil engraftment, GVHD, donor chimerism and overall survival (OS) and donor safety. Results 15 patients (10 females, 5 males), with median age 5.9 (3.1-17.2) years, were included. Diagnoses were beta-thalassemia (N=8), sickle cell disease (N=1), Diamond Blackfan anemia (N=1), Fanconi anemia (N=2), acute lymphoblastic leukemia (N=2) and myelodysplastic syndrome (N=1). 12 patients had genetic diseases, and, in 6 cases, donors were via preimplantation genetic diagnosis. All sibling CB units were stored in private family banks. Donors’ age at transplant was 0.8-6.8 years (median 1.6 years). Patients’ weights were greater than donors’ in all cases with a ratio of 1.1-7.9:1 (median 1.7:1). All donors underwent bone marrow collection (median: 175ml; range: 100-375ml) and were discharged home on the same day. Most CB units underwent washing prior to infusion. No infusion related serious adverse events were noted. Median BM CD34+ cell dose was 7.3 × 10^6 (range: 1.6-11.4). Median CB infused viable CD34+ cell dose was low 0.34 × 10^5 (range: 0.01-2.0). Viable infused CB CD3 doses ranged 0.5-8.3 × 10^6 (median: 2.5). All 15 patients engrafted with median neutrophil engraftment (ANC ≥500) at day +14 (range: 11-19 days) and median platelet engraftment (Plts ≥50,000) at day +35 (range: 27-43 days). No patient developed acute GvHD, while one patient developed limited chronic GvHD that resolved. T-cell reconstitution occurred at 1-7 months post-transplant in 13 evaluable patients. Donor chimerism was 100% (n=10) and 81-99% (n=5). With a median follow-up of 5.2 years (range: 5-16.9 months), all 15 patients are alive, disease-free. SUMMARY When CB units from HLA identical siblings are available and donors are able to undergo BM collection, this combination of grafts for transplantation has shown excellent outcomes, and this approach is our current practice. A retrospective review is underway comparing this approach with BM or CB only grafts to confirm advantage of a combined grafting strategy.

Post Transplant Cyclophosphamide Following Myeloablative TBI As a Conditioning Regimen for High-Risk Patients with AML Who Relapse after Transplant with Busulfan-Containing Regimen

Introduction Allogeneic HSCT (alloHSCT) offers a potential cure for patients with AML; however, 40% of AML patients receiving alloHSCT will experience relapsed disease. Second alloHSCT can offer the best long-term survival but is associated with significant toxicity. Preliminary data suggests that TBI only preparative regimen with post-transplant HD Cy is associated with lower TRM compared to TBI/Cy. Methods We report on four patients with AML who experienced relapsed disease following alloHSCT with busulfan-containing preparative regimen. All patients received re-induction chemotherapy and 3 achieved remission. Two patients had significant pre-existing morbidities prior to transplant, and one patient had refractory disease. Each patient received a second alloHSCT transplant using a TBI only preparative regimen (1200-1320 cGy) and GVHD prophylaxis included HD Cy 50mg/kg/daily on Days +3 and +4 as well as tacrolimus and MMF starting on Day +5. MMF was discontinued at Day +30 post-transplant. Three patients received bone marrow from 10/10 HLA-matched unrelated donors. One patient received PBSC from an HLA matched parent donor. Results All four patients tolerated transplant with no transplant related mortality and no grade 3 toxicity. All patients achieved neutrophil and platelet engraftment at an average of 19.5 (range 14-25) and 19 (range 15-23) days post transplant, respectively. Fifty percent of the patients developed acute Grade I-II skin GVHD. One patient developed mild, limited chronic GVHD. All patients are currently alive and are at least one year post second-transplant. Three of the four (75%) patients are off immune suppression and remain in remission at 14, 15 and 20 months post HSCT. Conclusion TBI only preparative regimen with post transplant HD Cy may offer an alternative treatment option for AML patients who experience relapse following a prior busulfan-containing alloHSCT.

Myeloablative Conditioning with Alemtuzumab in Matched Related Donor Hematopoietic Cell Transplant for Sickle Cell Disease Prevents Graft-Versus-Host Disease without Compromising Engraftment

Introduction:Matched related donor (MRD) hematopoietic cell transplant (HCT) is an accepted treatment for sickle cell disease (SCD) despite risk of graft-versus-host disease and graft rejection. Alemtuzumab is a potent lymphocytic medication that can reduce the risk of GVHD; however, it is associated with mixed donor chimerism (MDC) and graft loss when used with submyeloablative conditioning. We explored the use of myeloablative chemotherapy in conjunction with alemtuzumab in MRD HCT for SCD as a method to concurrently prevent GVHD and promote durable engraftment.Methods:We retrospectively reviewed engraftment, GVHD and survival for patients that underwent MRD HCT for SCD at Texas Children's Hospital between 2003-2017. All patients received busulfan dose adjusted to achieve target area under the curve of 800-1200μM per minute with doses administered intravenously every 6 hours for 4 days and cyclophosphamide 50mg/kg daily for 4 days. GVHD prophylaxis included intravenous alemtuzumab daily for 3-4 doses starting on day -5 (5-15kg=3mg, 15-30kg=5mg, >30kg= 10mg daily), methotrexate and a calcineurin inhibitor.Donor chimerism was evaluated via short tandem repeats (STR) or fluorescent-in-situ hybridization (FISH) of nucleated cells from the peripheral blood. If MDC was detected, follow-up chimerism studies were obtained every 1-4 weeks until stabilization on 2 or more consecutive evaluations. Persistent MDC was defined by the presence of recipient cells on 2 consecutive evaluations without return to full donor chimerism at last follow-up.Results:Thirty-eight consecutive patients underwent MRD transplant (3 non-sibling and 35 sibling) with a median age at transplant of 8.6 yrs (range: 2.9-18.4yr). Stem cell source consisted of bone marrow grafts for all patients. Two patients concurrently received cord blood from the same donor to augment cell dose. Neutrophil engraftment was achieved in all patients at a median time of 19 days (range: 13-24 days). Incidence of persistent MDC was 62.8% with a median last chimerism of 94% donor cells (range: 24-100%). Three of 22 patients (13.6%) with persistent MDC had <50% donor cells. The single patient with severe MDC <25% stabilized at 24% at 2 yrs post-HCT with concurrent Hgb S <50% on electrophoresis reflective of sickle cell trait in the donor. Graft rejection and recurrence of SCD related symptoms (vaso-occlusive crises, acute chest syndrome, stroke) were not observed in any patient at last follow-up. No additional cell products were given to manage mixed chimerism in any patient. Overall incidence of acute GVHD and severe acute GVHD (grade II-IV) were 26.3% and 5.3%, respectively. One patient developed limited chronic GVHD. Overall survival was 94.7% with a median time to last follow-up of 2.9 yrs (range: 90-4627 days). Two deaths occurred secondary to transplant-related complications including 1 death <100 days from HCT due to disseminated Mycobacterium tuberculosis and 1 secondary to hemophagocytic syndrome of uncertain etiology on day +318 from HCT.Conclusions:Myeloablative conditioning was well tolerated in this patient population, and the addition of alemtuzumab minimized occurrence of severe GVHD. While MDC was observed, chimerism stabilized at >50% donor cells in most patients and no graft rejection or recurrence of SCD occurred with a median follow-up of 2.9 yrs. The use of this regimen may be a promising approach to achieve low rates of GVHD while maintaining low rates of transplant related complications for patients with SCD that can tolerate myeloablative chemotherapy. DisclosuresNo relevant conflicts of interest to declare.

Allogeneic haematopoietic cell transplantation offers the chance of cure for patients with transformed follicular lymphoma.

In patients with follicular lymphoma, secondary transformation to aggressive lymphoma (tFL) implies a poor prognosis. In principle, allogeneic haematopoietic cell transplantation (allo-HCT) offers a chance of cure for tFL but is rarely practiced. Aim of this retrospective multicenter study was to define the actual significance of allo-HCT in treatment of tFL. The database of the German Registry for Stem Cell Transplantation (DRST) was screened for patients who underwent allo-HCT for tFL 1998-2008. Confirmation of tFL-diagnosis by local and/or pathologists of the National NHL Board was mandatory for enrolment. Gaps in reported EBMT Minimum Essential Data datasets (MED-A) were filled by local DRST data managers. Relevant HCT outcome variables were evaluated by uni- and multivariate statistical analysis. Median age of enrolled 33 patients was 51years with a post allo-HCT median follow-up of 7.1years of surviving patients. At time of HCT 24/33 patients had chemosensitive disease. In 24/33 patients reduced intensity conditioning (RIC) was used. Estimated 1, 2, 5-year overall survival (OS) and event-free survival rates were 49/39/33, and 33/30/24%. Cumulative 100days non-relapse mortality was 25%. Chemosensitive disease, RIC, and limited chronic GvHD were identified as independent prognostic factors for OS. Allo-HCT offers the chance of cure for tFL.

Clonal Deletion Plays a Major Role to Achieve Immune Tolerance after Reduced Intensity Unrelated Donor Cord Blood Transplantation (UCBT)

Generation of tolerance to transplanted hematopoietic cells or organs is essential if elimination of immunosuppressive therapy (IST) is desired. Immune tolerance is the expected outcome after successful hematopoietic stem cell transplantation (HSCT). It is characterized byimmunocompetencewithout any alloreactivity (GVHD) in the absence of IST. However, the mechanism(s) required to prevent alloreactivity are not fully understood. Both central (clonal deletion) and peripheral (anergy, suppression byTreg, Tr1) mechanisms are suspected. In this study, we set up serial experiments to test for these mechanisms after unrelated donor cord blood transplant (CBT) in theGvHdirection. We also studied these mechanisms at the time of GVHD.Methods:Seven patients (age range from 1m to 9y) with non-malignant diseases were transplanted and studied for host-specific alloreactivity following reduced intensity conditioning (RIC) regimen (NCT01852370) that also utilizedAlemtuzumab(1.2mg/kg) ~ 2 weeks prior to UCBT. Five of the patients were off immunosuppression therapy when blood was drawn (6 -12 months after UCBT) while two were not and had either limited chronic GVHD or recently resolved acute GVHD. Donor T cellchimerismat the time of blood draw was a median 97% (range 87-100%). Purified T cell responses to host APC (EBV-LCL for EBV seronegative patients, or monocyte derived DC) were measured by mixed lymphocyte reaction (MLR) and cytotoxic lymphocyte (CTL) reaction after 5 or 7 days in culture, respectively. Th1/Th2/Th17 cytokines along with IL-10 secreted during MLR were quantified from day 5 supernatant by bio-plexassay. To track host-reactive T cell clones, TCRbrepertoire was monitored and quantitated using targeted amplification of rearranged TCR genes followed by high-throughput sequencing (Adaptive Biotechnologies®). The data was analyzed withImmunoSEQ® Analyzer Software. To further identify the key mechanism(s) of tolerance, we attempted to break tolerance by inhibiting or amplifying putative pathways using the following methods: Regulatory T cell (Treg) deletion was achieved byDenileukindiftitox(Ontak) treatment prior to MLR and CTL reactions. Involvement of Tr1 or anergy was examined either by blocking IL10R or by adding low dose IL2, respectively.Results and Discussion:Patients with clinical tolerance (n=5): There was no significant proliferative or cytotoxic T cell response towards recipient APC while T cells responded vigorously to 3rd party APC (Fig 1, 2). Similarly, Th1/Th2/Th17 cytokine profiles revealed recipient-specific non-responsiveness by both proliferation and cytokine secretion (Fig 1A,B) fulfilling a critical tenet of tolerance in three independent assays (MLR, CTL, cytokine secretion). In addition, tracking TCRb clonal profiles withImmunoSEQ® revealed the disappearance of recipient-specific T cell clones that were amplified from the cord blood graft itself by 7 days of stimulation with purified host APC (labeled pre-UCBT in Fig 1.C). There was no indication ofTreg or Tr1 involvement in sustaining tolerance since neither deletion ofTregs by IL-2 IT, nor IL-10R blockade had any impact on T cell hypo-reactivity in MLR, CTL, andbioplex assays. Interestingly, addition of IL-2 in MLR did enhance T cell proliferative responses in 1 out of 5 tolerant patients tested, but did not activate host-specific CTL responses. Nevertheless, here we can not exclude the possibility ofanergy playing some role in preventing host-specific alloreactivity.Patients with GvHD at time of examination: T cells isolated from patients with recently resolved or still active limited chrGVHD receiving some IST (n=2) did proliferate against recipient APC in MLR, but were not cytotoxic against host APC (Fig 3). IL-2 and IL-13 secretion towards host APC was detectable in both (data not shown).In summary, the rapid acquisition of immune tolerance in theGvH direction post-UCBT on our prospective RIC clinical trial is characterized by hypo-reactivity in all assays employed towards host APC. The proliferation, cytotoxicity, and TH1/TH2, TH17 cytokine secretion data suggest that host-specific clonal deletion is a significant mechanism of tolerance in most if not all patients. In one, there is possibility foranergy as exogenous low dose IL-2 was able to overcome absent proliferation by MLR, while having no impact on host-reactive CTL activity or TH1/TH2/Th17 cytokine secretion. DisclosuresNo relevant conflicts of interest to declare.

Reduced Non Relapse Mortality (NRM) and Survivable Acute Graft Versus Host Disease (GVHD) in the Current Era of Myeloablative Ex Vivo T-Cell Depleted (TCD) Transplantation

Introduction:Little is known about the lethality of acute GVHD (aGVHD) in T -cell depleted (TCD) allogeneic hematopoietic stem cell transplantation (HSCT). We examined the incidence of aGVHD and its relative contribution to non relapse mortality (NRM) in a cohort of consecutive TCD HSCT at a single institute.Methods:We report 132 consecutive subjects who had undergone TCD HLA-identical sibling HSCT between 2006 and 2016 for hematologic malignancies. All subjects received conditioning with Fludarabine 125mg/m2, Cytoxan 120 mg/kg and 1200 cGy total body irradiation (TBI) (<age 55 years) or 400-600 cGy (³age 55) followed by either a CD34+ selected (n=112) or CD3/19 depleted (n=20) peripheral blood stem cell graft with a T cell addback of 5-50x10e4CD3+/kg (Miltenyi CliniMACS, resulting in 3.5 to 4-log TCD). Low dose cyclosporine was used until day 21 for GVHD prophylaxis.Thirty-six subjects were over the age of 55 years, 66 were females and 66 were males. Transplant indications were acute leukemia (92), myelodysplastic / myeloproliferative syndromes (26), lymphoid malignancies (7) and chronic myelogenous or myelomonocytic leukemia (7). Fifty-three percent of subjects were at a high risk of relapse. The median follow-up post HSCT was 4.3 years.Results:The incidence of Grade 1-2 and 3-4 aGVHD were 51.6% and 19%, respectively. Of these, 15% of aGVHD was steroid refractory and was treated with infliximab/basiliximab or with mesenchymal stromal cells. Extensive or limited chronic GvHD was observed in 30% and 24% of subjects. 74% of those at risk developed cytomegalovirus (CMV) reactivation. The Kaplan-Meier (KM) estimate for overall survival (OS), NRM and cumulative incidence of relapse (CIR) for the entire cohort was 71%, 14.6% and 24% respectively at one year, and 52%, 32.5% and 39% at 5 years. We considered the impact of CMV reactivation, slow donor lymphoid chimerism and steroid refractory aGVHD on NRM. However there was no significant impact from CMV reactivation or slow (> 31 days) achievement of complete donor lymphoid chimerism. Significantly improved outcomes were noted for those transplanted beyond 2012: OS, NRM and CIR being 82%,6.2% and 20% at one year, and 68%, 6.2% and 41% at 3 years. Cox proportionate hazard modeling identified steroid refractory aGVHD (HR 4.0, P=0.007) and transplant prior to 2012 (HR 6.7, P=0.001) as significant factors impacting NRM.Conclusions:T cell addback after ex vivo TCD HSCT was associated with a significant burden of aGVHD. Steroid refractory aGVHD impacted NRM, but slow lymphoid engraftment, disease risk, CMV reactivation and age did not. Significant improvements in NRM in the current era suggest greatly improved salvage of steroid refractory aGVHD. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Family Mismatched Donor Transplantation for Myelofibrosis: A Retrospective Analysis of the EBMT Chronic Leukaemia Working Party

Background: Allogeneic stem cell transplantation is a treatment option for patients with advanced myelofibrosis. Problems encountered include an increased risk of delayed or poor engraftment and in the mismatched unrelated donor setting a higher rate of GVHD and particularly poor outcomes. As for other indications for allogeneic stem cell transplants, patients for whom either a matched sibling or matched unrelated donor is not available are considered for either a double umbilical cord blood, a mismatched unrelated donor or haploidentical stem cell transplant. Data on the latter option are limited and we reviewed registry data on all family mismatched donor transplants performed between 2001 and 2015 and reported to the EBMT registry.Results: Records retrieved 69 patients with myelofibrosis transplanted between November 2001 and November 2015. 44 (64%) were male. 50 (74%) had primary myelofibrosis,18 (27%) had secondary myelofibrosis (6 from ET, 5 from PRV and 7 others) and unknown 1(2%). Of 25 patients for whom the JAK2 V617F mutation status was known, 15 (22%) harboured the mutation. Patient Karnofsky performance status was > 70% in 98%.Of the mismatched family donors, 47 (68%) were male and 22 (31%) female. Donors were HLA mismatched at 1 locus in 12 (17%) and 2 or more loci in 48 (69%). Donor-recipient serology combinations were CMV -/- in 8 (12%), +/- in 4 (6%), -/+ in 15 (22%) and +/+ in 34 (49%) missing 8 (12%).Bone marrow was the stem cell source in 34 (49%) and peripheral blood in 35 (51%). The median total nucleated cell count (TNC) infused was 7.5x108/kg (range 2.3-21x108/kg) from data available in 17 patients. The median CD34+ cell dose was 6.9x106/kg (range 1.9-18.18x106/kg) from data available in 19 patients.Conditioning was myeloablative in 48 (70%) and RIC in 21 (30%) The conditioning regimes were varied but the predominant ones were Fludarabine, Busulphan, ATG (FBATG) and Thiotepa, Busulphan, Fludarabine (TBF). TBI was administered in 8 (12%) and in vivo T cell depletion in 22 (32%), ex-vivo T cell depletion in 5 (7%) patients. GVHD prophylaxis varied with post transplant Cyclophosphamide administered in 34/67 (49%) and ATG in 19/67 patients (28%).Neutrophil engraftment was established in 53 (82%) at a median of 20 days (range 11-83). Primary graft failure occurred in 8 (12%) and secondary graft failure in 4 (6%). This occurred at a median of 12 months (range 4.5-35 months). Eleven of these patients had a second allograft at a mean interval of 6.4 months. Responses to the first allograft (censoring for patients who had a second allograft) with data available in 45 patients, showed that complete remission was achieved in 35 patients (78%), 6 (13%) were never in CR and 4 (9%) were not evaluable.The cumulative incidence of grade II-IV acute GvHD at 100 days was 12% (95% CI 4-21%) and for grade III-IV acute GvHD at 100 days it was 5% (95% CI 3-11%). Data for chronic GVHD was valid in 49 patients. The cumulative incidence of chronic GvHD at 2 years was 62% (95% CI 47-76%). The cumulative incidence of limited cGvHD was 45% (95% CI 31-59%) whereas the cumulative incidence of extensive cGvHD was 10% (95% CI 2-19%).The median follow up was 24 months (95% CI 13-35 months). The 2-year OS was 51% (95% CI 37-76%) and the 5-year OS was 38% (95% CI 21-55%). The 2-year RFS was 44% (95% CI 30-59%) and the 5-year RFS was 31% (95% CI 15-48%). The 2 year cumulative incidence of relapse was 14% (95% CI 5-24%). The 2 year NRM was 41% (95% CI 28-55%), which increased to 54% (95% CI 37-72%) at 5 years.The main causes of death were infection (16, 24%), GVHD (7, 10%) organ damage or failure (3, 5%), relapse/disease progression (1, 2%) and secondary malignancy or PTLD (1, 2%). On univariate analysis there was no significant effect of recipient gender, donor gender, degree of HLA mismatch 1 vs >1 Ag MM, CMV matching between donor and recipient, primary or secondary MF, disease stage at transplant (chronic versus advanced phase), conditioning intensity, conditioning regimen, GVHD prophylaxis with ATG or post transplant cyclophosphamide or stem cell source on overall survival.Conclusion: Concerns regarding engraftment and secondary graft failure have excluded patients with myelofibrosis from clinical trials of mismatched related donor transplant. The data suggest that engraftment is feasible, and PFS and OS can be attained with limited severe chronic GVHD with family mismatched donors in this setting. DisclosuresCiceri:MolMed SpA: Consultancy.

Allo-HCT from MUD/MRD for Paroxysmal Nocturnal Hemoglobinuria - 12 Years of Experience

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired clonal abnormality of hematopoietic stem cell leading to lack of phosphatidylinositol glycoproteins, sensitizing cells to complement-mediated lysis. Despite the efficient symptomatic treatment of hemolytic PNH with eculizumab, allo-HCT is the only curative treatment for the disease, although outcomes presented in the past were controversial.Material and methods: We report 41 allo-HCTs: 37 from MUD and 4 from MRD performed for PNH in 2004-2016. Median age of recipients was 29(20-62) years and donors 30(19-53), median time from diagnosis to allo-HCT was 16(2-307) months. Median size of PNH clone was 80% granulocytes (0.5%-100%). Indication for allo-HCT was PNH with aplastic/hypoplastic bone marrow (19 pts), MDS (2 pts), overlapping MDS/aplasia (3 pts), severe course of PNH with hemolytic crises and transfusion-dependency without access to eculizumab (17 pts). Additional risk factors were Budd-Chiari syndrome and hepatosplenomegaly (1 pt), history of renal insufficiency requiring hemodialyses (2 pts), chronic hepatitis B (1 pt) and C (1 pt). The preparative regimen consisted of treosulfan 3x14 g/m2 plus fludarabine 5x30 mg/m2 (31 pts) or treosulfan 2x10 g/m2 plus cyclophosphamide 4x40 mg/kg (10 pts). Standard GVHD prophylaxis consisted of cyclosporine-A, methotrexate and pre-transplant ATG in MUD-HCT. 2 pts instead of cyclosporine-A received mycophenolate mofetil and tacrolimus. Source of cells was bone marrow (13 pts) or peripheral blood (28 pts) with median 6.3x108NC/kg, 5.7x106CD34+cells/kg, 24.7x107CD3+cells/kg. Myeloablation was complete in all pts with median 9(1-20) days of absolute agranulocytosis <0.1 G/l. Median number of transfused RBC and platelets units was 9(0-16) and 8(2-18).Results: All pts engrafted, median counts of granulocytes 0.5 G/l, platelets 50 G/l and Hb 10 g/dl were achieved on days 17.5(10-33), 16(9-39) and 19.5(11-34). Acute GVHD grade I,II and III was present in 16, 7 and 3 pt, limited and extensive chronic GVHD respectively in 11 and 3 pts. LDH decreased by 73%(5%-91%) in first 30 days indicating disappearance of hemolysis. 100% donor chimerism was achieved in all pts. In 1 patient donor chimerism decreased to 81% what was treated with donor lymphocytes infusion (DLI). 3 patients died, 1 previously hemodialysed pt died on day +102 due to nephrotoxicity complicating adenoviral/CMV hemorrhagic cystitis, two other SAA patients with PNH clone<10% died on days +56 due to severe pulmonary infection and +114 due to aGvHD-III and multi organ failure. Complications in survivors were FUO (10 pts), CMV reactivation (13), VOD (1), neurotoxicity (1), venal thrombosis (1), hemorrhagic cystitis (4) and mucositis (8). 38 pts (92.7%) are alive 4.2 (0.4-12) years post-transplant and are doing well without treatment. Complete disappearance of PNH clone was confirmed by flow cytometry in all surviving pts.Conclusions: Allo-HCT with treosulfan-based conditioning is effective and well tolerated curative therapy for PNH. DisclosuresNo relevant conflicts of interest to declare.

Ibrutinib for Bridging to Allogeneic Hematopoietic Stem Cell Transplantation (alloHCT) in Chronic Lymphocytic Leukemia (CLL) and Mantle Cell Lymphoma (MCL) Is Safe and Effective: First Results of a Survey By the Chronic Malignancy and the Lymphoma Working Parties of the EBMT

BACKGROUND: The advent of the Bruton's tyrosine kinase inhibitor ibrutinib has improved the outlook of patients with CLL and MCL failing chemoimmunotherapy (CIT). However, the impact of ibrutinib on the feasibility and safety of a subsequent alloHCT is unknown. Here we present results of the ibrutinib cohort of an ongoing EBMT survey on the outcome of alloHCT following prior exposure to pathway inhibitors (PI) in patients with CLL or lymphoma (EBMT study code LWP 2013-N-03/CMWP 44204425).DESIGN: Eligible were patients aged >18 years registered with the EBMT data office for a planned alloHCT for CLL or lymphoma after pre-exposure to ibrutinib at any time before transplant. Baseline patient, disease, and transplant data were collected from MED-A forms. Centers were requested to provide additional treatment and follow-up information. Statistical analysis used Gray’s test to assess the impact of baseline characteristics on the cumulative incidence of relapse (REL) in a competing risk framework.RESULTS: As of July 4, 2016, 38 patients (84% male) were evaluable in the ibrutinib cohort. Diagnosis was CLL in 28 patients, MCL in 9 patients, and follicular lymphoma (FL) in 1 patient. The median age was 51 (33-68) years and the median number of treatment lines prior to ibrutinib 2 (1-9). Eight of the 9 patients with MCL but none of the other patients had a prior autoHCT. Patients had been on ibrutinib for a median of 190 (39-432) days. In 2 patients, ibrutinib had been stopped because of disease progression >100d before transplant, whereas the interval between ibrutinib withdrawal and alloHCT was 15-100d in 30%, 4-14d in 51%, and 0-1d in 14% of the patients. Of the CLL patients, 43% had a TP53 lesion, and 87% and 79% met at least one of the 2007 and 2014 EBMT criteria for high-risk CLL, respectively, including PI failure in 29%. Disease status at alloHCT was sensitive in 78% of the CLL patients, and in 60% of the patients with lymphoma. Conditioning was reduced-intensity in 60% of the transplants and included in-vivo T cell depletion with ATG (71%) or alemtuzumab (11%) in the majority of cases. Donors were identical siblings in 26%, matched unrelated in 66%, and partially matched unrelated in 8%, with PBSC (89%) being the predominant stem cell source (bone marrow 8%, cord blood 3%). The median time to reach neutrophils of >0.5/nl and platelets of >20/nl was 17 (10-26) and 15 (10-46) d post transplant, respectively. Acute GVHD grade 2-4 (3-4) was observed in 37% (10%) of 30 evaluable patients, and limited and extensive chronic GVHD occurred in 24% and 16% of 25 patients at risk. With a median observation time of survivors of 8 (1-24) months, there were only 2 non-relapse deaths, translating into a 1-year non-relapse mortality (NRM) of 6% (95%CI 0-15%). 1-year REL, progression-free survival, and overall survival was 36%, 61%, and 73% for CLL, and 14%, 75%, and 75% for lymphoma. In the 25 evaluable patients with CLL, PI-sensitive compared to refractory disease status at alloHCT tended to be associated with a lower 1-y REL (29% vs 60%; p 0.071), whereas prior PI failure, TP53 status, duration of ibrutinib exposure, interval between ibrutinib withdrawal and alloHCT, and conditioning intensity had no significant impact on REL.CONCLUSIONS: Ibrutinib for bridging to alloHCT for CLL and MCL does not appear to adversely affect engraftment, GVHD risk, and NRM. Patients with CLL still responding to ibrutinib at the time of alloHCT might benefit from ibrutinib bridging as our preliminary results indicate that also after PI exposure sensitive disease translates into a lower risk of relapse. Therefore, ibrutinib may improve the perspective of CIT-refractory patients scheduled for alloHCT. The optimum timing of ibrutinib administration in the interrelation to alloHCT in CLL and MCL needs to be defined by additional studies. DisclosuresDreger:Gilead: Consultancy; Janssen: Consultancy; Novartis: Speakers Bureau; Gilead: Speakers Bureau; Novartis: Consultancy; Roche: Consultancy. Michallet:Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Astellas Pharma: Consultancy, Honoraria; MSD: Consultancy, Honoraria; Genzyme: Consultancy, Honoraria. Berg:Celgene: Other: Travel Funding; Astellas: Other: Travel Funding; Alexion: Other: Travel Funding. Niederwieser:Novartis Oncology Europe: Research Funding, Speakers Bureau; Amgen: Speakers Bureau. Montoto:Gilead: Research Funding; Roche: Honoraria. Schetelig:Sanofi: Honoraria.

Sequential Allogeneic Transplantation for Multiple Myeloma Patient in Early Relapse Post-Autograft

Multiple myeloma (MM) remains mostly incurable despite novel therapeutic approaches. Allogeneic stem cell transplantation (ASCT) in MM could be the only curative treatment but is associated with a high morbidity and mortality, and relapses remain, mainly in high risk (17p deletion, (4;14) translocation, plasma cell leukemia, extramedullary disease or early relapse post-autograft).In refractory or poor risk cytogenetic acute myeloid leukemia (AML), sequential conditioning, followed by prophylactic immunomodulation with donor lymphocyte infusion (DLI), seems improve the outcome, compared to conventional ASCT regimens.Based on this sequential approach ASCT, we developed a sequential conditioning for MM, with a systematic immunomodulation strategy. The conditioning included melphalan 100mg/m² at day-10, followed by FB2 conditioning (fludarabine 30mg/m²/d day-6, -5,-4, -3, -2, busulphan 3.2mg/kg/d day-5, -4 and horse antithymoglobulin 2.5mg/kg/d day-3, -2). Prophylaxis of GVHD included cyclosporine and methotrexate according to ABO compatibility. This schema was proposed for young patients with early relapse after autograft (<1 year). The aim of the study was to evaluate feasibility and safety.In the absence of GVHD, 2 cycles of bortezomib (1,3mg/m² day 1, 4, 8, 11) without steroids followed by 3 escalated doses of DLI.Four patients received this sequential conditioning. All were low risk cytogenetic but were in early relapse post-autograft. Patients' characteristics are shown in table1. One patient received 2 autologous transplantation (patient 3). They received 2 or 3 lines of combination chemotherapy before allograft including: bortezomib (n=4), lenalidomide (n=4), pomalidomide (n=1). All of them were in partial response at time of ASCT.All patients were grafted with peripheral blood stem cells (median dose = 8 CD34+/kg [5.44-8.15]). Only one patient received methotrexate in addition to cyclosporine for GVH prophylaxis for ABO minor incompatibility.Two patients presented grade 3-4 acute GVHD: 1 was steroid-resistant and responded secondary to ruxolitinib, but unfortunately he died of septic shock. Patient 4 was in sCR with MRD negative 6 months post ASCT but currently presents signs of disease evolution without treatment criteria at 10 month.Two patients didn't presented GVHD and received prophylactic schedule with bortezomib followed by escalated doses of DLI. Three doses of DLI were planned: first dose=5x106 CD3+/kg, second dose=1x107CD3+/kg and third dose=5x107CD3+/kg. Only 2 doses were administrated because patients relapsed before the third dose. Patient 3 presented limited chronic GVHD (oral lichen) after DLI2 but relapsed 11 months post ASCT. Patient 1 relapsed at 10 months: they were retreated with pomalidomide and are now alive.In conclusion, sequential conditioning for young patients with MM in early relapse post-autograft is feasible. The addition of melphalan to the classical FB2 is safe without early toxicity (no mortality related to transplantation at day +100). 2 patients however presented severe acute GVHD. Despite the post ASCT immunomodulation, this procedure was not capable to control the disease. The optimization of conditioning procedure, the post-allograft immunomodulation and a maintenance therapy may provide a benefit to patients and, thus, requires further study. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Successful Renal Transplant Tolerance Following a Haplo-Identical Allogenic Hematopoietic Stem Cell Transplant - a Case Report and Review of Literature

Background:Immune tolerance in solid organ transplantation is a continuing challenge because of the risks of acute and chronic rejection and severe adverse effects of extended exposure to immunosuppressive drugs (IsD). Therefore, the goal of transplant tolerance is to prevent both acute and chronic rejection without use of prolonged IsD. Owen [Science 1945] and Billingham [Nature 1953] demonstrated solid organ transplant tolerance by inducing stable donor:host chimerism with infusion of hematopoietic stem cells (HSCT). Subsequently, various animal studies and clinical trials demonstrated the ability ,of HSCT to induce solid organ transplant tolerance. Herein we present a case of an haplo-identical (HaploTx) HSC for the treatment of multiple myeloma (MM) followed thereafter by a renal transplant from the same donor. We discuss this case and results reported in the literature.Case Report:A 25-year-old male presented to the ER with complaints of fatigue, nausea, and intermittent vomiting for six months. Ultimately, he was diagnosed with kappa light chain multiple myeloma, International Staging System 3, with light chain cast nephropathy on renal biopsy (Table I). He initiated hemodialysis for worsening renal function and uncontrolled hypertension. He began chemotherapy with bortezomib, lenalidomide and dexamethasone (VRd). He responded well to chemotherapy achieving a partial remission. His free kappa light chains decreased from 2570 mg/L to 63 mg/L after 3 cycles of VRd. Considering his age, response to chemotherapy, and end stage renal disease requiring hemodialysis, the patient was offered an allogenic HSCT to be followed 1 year thereafter by a renal transplant from the same donor. Since he did not have any matched sibling donors, he underwent an HaploTx from his father after a conditioning regimen with fludarabine, cyclophosphamide and total body irradiation followed by infusion of bone marrow cells. The post-transplant IsD consisted of tacrolimus, mycophenolate mofetil and high dose cyclophosphamide (days 3 and 4). He achieved complete chimerism on d + 28 and maintained one-year post transplant. He did not develop acute GVHD but experienced limited chronic GVHD (eyes and mouth) 14-18 weeks after HSCT for which he was started on low dose prednisone and topical steroids. One year after HSCT he received renal allograft from his father. He continued to take tacrolimus post-transplant, which was tapered off by nine months. Two years following his renal transplant, his serum creatinine is 1.19mg/dl and his MM remains in complete remission (Figure I).Conclusion:Stem-cell-based therapies used in order to induce durable transplant tolerance are currently under development. Data from early trials suggest successful and durable IsD tapering in patients with combined kidney and HSCT associated with prolonged graft survival. Further, comorbidities associated with allografts have been decreased including hypertension, diabetes, and hyperlipidemia. Data from other case centers also report successful and durable IsD tapering in patients with combined kidney and HSCT associated with prolonged graft survival. However, patients with combined kidney and HSCT did develop more AKI post-transplant. Other concerns related to combined transplant are sudden death, GVHD and secondary malignancy. Ongoing clinical trials are being conducted to induce transplant tolerance to achieve either mixed chimerism and full chimerism. Results from the early clinical trials look promising, but more data is needed to assess long-term safety and efficacy. [Display omitted] [Display omitted] DisclosuresSiegel:Amgen: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; Takeda: Honoraria, Speakers Bureau; Celgene: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Merck: Honoraria. Richter:Takeda: Consultancy, Speakers Bureau; Jannsen: Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau. Biran:Novartis: Speakers Bureau; Celgene: Speakers Bureau; Takeda: Speakers Bureau; Amgen: Speakers Bureau. Skarbnik:Abbvie: Consultancy; Seattle Genetics: Speakers Bureau; Gilead Sciences: Speakers Bureau; Genentech: Speakers Bureau; Pharmacyclics: Consultancy. Vesole:Celgene: Speakers Bureau; Novartis: Speakers Bureau; Takeda: Speakers Bureau; Janssen: Speakers Bureau; Amgen: Speakers Bureau.

Allogeneic hematopoietic cell transplantation as curative therapy for non-transformed follicular lymphomas.

Allogeneic hematopoietic cell transplantation (HCT) offers the chance of cure for patients with non-transformed follicular lymphoma (FL), but is associated with the risk of non-relapse mortality (NRM). The aim of this study was to identify subgroups of FL patients who benefit from HCT. The European Society for Blood and Marrow Transplantation (EBMT) Minimum-Essential-A Data of 146 consecutive patients who received HCT for FL between 1998 and 2008 were extracted from the database of the German Registry 'DRST'. Diagnosis of FL was verified by contact with the reference pathologists. Estimated 1-, 2- and 5-year overall survivals (OS) were 67%, 60% and 53%, respectively. Day 100 NRM was 15%. Thirteen out of 33 patients (40%) with treatment-refractory disease (RD) at the time of transplantation survived long term. Univariate statistical analysis suggested limited chronic GvHD, donor age ⩽42 years and TBI-based conditioning in treatment refractory patients to correlate with favorable OS. Independent prognostic factors for OS were treatment-sensitive disease and limited chronic GvHD for the whole cohort, and additionally TBI-based conditioning for the treatment refractory subgroup. In contrast, patient age ⩾55 years had no impact on outcome. Thus, HCT for FL is associated with acceptable NRM, and offers a substantial chance of cure for patients with RD or advanced age. Donors ⩽42 years should be preferred if available.