Nonmyeloablative Allogeneic Stem Cell Transplantation Research Articles

Non-Myeloablative (NMA) Allogeneic Hematopoietic Stem Cell Transplant for the Treatment of Patients with Hematologic Malignancies Using Busulfan, Fludarabine and Total Body Irradiation (Bu/Flu/TBI) Conditioining: Results of a Phase II Trial

Non-Myeloablative (NMA) Allogeneic Hematopoietic Stem Cell Transplant for the Treatment of Patients with Hematologic Malignancies Using Busulfan, Fludarabine and Total Body Irradiation (Bu/Flu/TBI) Conditioining: Results of a Phase II Trial

Nonmyeloablative Allogeneic Hematopoietic Stem Cell Transplant in Patients with End Stage Renal Disease Requiring Dialysis – a Single Institution Experience

s / Biol Blood Marrow Transplant 20 (2014) S211eS256 S251 patients with biopsy-proven disease, 43% had lymphocytosis. 100% of patients with CMV viremia and no CMV gut disease were lymphopenic. There did not appear to be any association between CMV PCR copy number and absolute lymphocyte count (r1⁄40.016; p1⁄40.49). There was no apparent pattern or relationship between CMV PCR copy number and degree of cytopathic changes on intestinal biopsy. Conclusion: We hypothesized that all patients with gutassociated CMV disease would have corresponding CMV viremia. One patient with biopsy-proven disease had negative CMV PCR, so we are evaluating for potential sources of false positivity because gut-confined CMV (CMV disease without CMV viremia) is relatively uncommon in the HSCT setting. Our data support that a lack of CMV viremia does not rule out gut-associated CMV disease and that intestinal biopsy by EGD or colonoscopy is warranted in this patient population.

A Phase II Study of a Nonmyeloablative Allogeneic Stem Cell Transplant with Peritransplant Rituximab in Patients with B Cell Lymphoid Malignancies: Favorably Durable Event-Free Survival in Chemosensitive Patients

The aim of this prospective phase II trial was to determine the safety and efficacy of a nonmyeloablative conditioning program incorporating peritransplant rituximab in patients with CD20+ B cell non-Hodgkin lymphoma (B-NHL) receiving an allogeneic stem cell transplant (allo-SCT). Fifty-one adult B-NHL patients, with a median age of 54 years, were treated with cyclophosphamide, fludarabine, and 200 cGy of total body irradiation. Rituximab 375 mg/m2 was given on day −8 and in 4 weekly doses beginning day +21. Equine antithymocyte globulin was given to recipients of volunteer unrelated donor grafts. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and mycophenolate mofetil and tacrolimus, sirolimus, and methotrexate in 8 and 43 patients, respectively. Thirty-three patients received grafts from unrelated donors, and 18 received grafts from matched related donors. All patients engrafted. Full donor chimerism in bone marrow and peripheral T cells was seen in 92% and 89% of patients, respectively, at 3 months after allo-SCT. The cumulative incidence of grades II to IV acute GVHD at 6 months was 25% (95% confidence interval [CI], 13% to 38%) and grades III to IV was 11% (95% CI, 2% to 20%). The 2-year cumulative incidence of chronic GVHD was 29% (95% CI, 15% to 44%). The 2-year event-free and overall survival for all patients was 72% (95% CI, 59% to 85%) and 78% (95% CI, 66% to 90%), respectively. The 2-year event-free survival for chemosensitive patients was 84% (95% CI, 72% to 96%) compared with 30% (95% CI, 2% to 58%) for chemorefractory patients before allo-SCT (P < .001). This nonmyeloablative regimen, with peritransplant rituximab, is safe and effective in patients with B-NHL.

Outpatient Non-Myeloablative Allogeneic Stem Cell Transplantation For Myeloma Is Feasible, Efficacious and Associated With Low Transplant-Related Morbidity and Mortality

Aim/BackgroundReduced intensity/non-myeloablative allogeneic haemopoietic stem cell transplantation (allo HSCT) for myeloma following a myeloablative autologous stem cell transplant (ASCT), is associated with lower TRM rates than myeloablative allografting and has the potential to induce long term disease control through the well documented graft-versus-myeloma effect. Continuing attempts to reduce the procedure-related toxicity as well as resource utilisation are likely to result in the use of curative tandem auto-allo earlier in the disease course. We retrospectively reviewed the outcomes of 33 outpatient tandem autologous/non-myeloblative (NMA) conditioning allo HSCT referred to our institution. MethodsBetween May 2008 and December 2012, 33 patients were referred for tandem auto-allo procedures. Patients were transplanted either upfront (n=18) as part of their initial management or as a deferred procedure (n=15), usually as salvage following an initial autograft followed by maintenance/consolidation. Patients were transplanted upfront if they had one or more of the following high risk features: t(4;14) or t(14;16) translocations, 1q amplification, 1p and 17p deletion on cytogenetics/FISH; elevated LDH; stage III ISS disease or less than a PR with a novel agent-containing induction regimen. Patients were eligible for tandem auto-allo if they had achieved at least a PR to the latest therapy, had no significant co-morbidity and were less than 70 years of age. All autografts were conditioned with melphalan 200mg/m2 and an outpatient NMA allo HSCT timed to occur 3 months later using oral fludarabine 48mg/m2 on days -4 to -2 and 2Gy TBI on day 0 as conditioning. A target cell dose of 2 x 106/kg CD34+ donor stem cells were infused on day 0. Graft versus host disease prophylaxis consisted of cyclosporine and mycophenolate mofetil. ResultsThe median age for the entire cohort was 52 (range 39-65), 19 males and 15 females and the median follow up was 719 days (50-1733). The overall response rate post-allo HSCT was 26/33 (79%) with a significantly higher proportion of CR/VGPRs seen in those transplanted upfront rather than deferred (15/18 v 7/15; p=0.03). The majority of patients were transplanted as outpatients (29/33) and only 4 were admitted for social reasons. Transplant complications requiring admission in the first 30 days occurred in 15/33 (45%) of patients, with a median length of stay of 1.5 days, and only 4 patients were hospitalised for more than 7 days. Median nadir neutrophil and platelet counts were 0.5 x 109/L (range 0.1-1.1) and 94 x 109/L ( range 23-143) respectively across the entire cohort and no patient experienced graft failure. Acute GVHD occurred in 14 (44%) of patients, was mild in the majority of cases and only 3 (9%) developing severe GII-IV aGVHD. Manageable chronic GVHD occurred in 19/31 (61%) evaluable patients, there were no transplant-related deaths by day 100 and 2 patients died of infection (microbiologically-unconfirmed sepsis at day 240 and disseminated nocardia infection at day 1025), resulting in a TRM of 6%. At the time of analysis, 26 (79%) patients were alive including 15 (45%) in ongoing CR. The median OS for the entire cohort has not been reached and the median PFS for all patients is 2.8years. Patients allografted upfront had significantly longer PFS compared to those recipients of a deferred transplant procedure (median NR versus 1.2 years respectively; p=0.03) but there was no significant difference in OS at 2 years follow up. ConclusionTandem autologous/NMA allo HSCT for myeloma, when performed in the ambulatory setting, is feasible, well tolerated and associated with minimal toxicity and low TRM. Our results with outpatient tandem auto-allo compare favourably with ASCT and suggests allo HSCT may benefit selected patients earlier in their disease course. Disclosures:Spencer:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Incidence and Kinetics Of Full Donor Chimerism and The Impact Of Minimal Residual Disease Status Following Outpatient Non-Myeloablative Allogeneic Stem Cell Transplantation For Myeloma

BackgroundChimerism analysis is routinely performed following allogeneic haemopoietic stem cell transplantation (allo HSCT) as a means of monitoring donor engraftment and relapse risk, although its role in the management of allografted myeloma patients is controversial. Multiparameter flow cytometry (MFC) assessment of minimal residual disease has been demonstrated to predict outcome following myeloblative autologous stem cell transplantation (ASCT) in multiple myeloma (MM). Relapse and disease progression is the principle cause of allograft failure and the detection of minimal residual disease (MRD) following tandem autologous/non-myeloablative(NMA) allo HSCT may potentially identify patients at risk of early relapse and provide a platform for early post-allograft therapy designed to further cytoreduce or enhance alloreactive T cell function and graft versus myeloma effect. AimTo evaluate the impact of MRD assessment performed at 3 months post-allo HSCT on PFS and OS and document the incidence and kinetics of full donor chimerism (FDC) in a cohort of myeloma patients undergoing tandem ASCT/outpatient non-myeloablative (NMA) allogeneic HSCT for MM. MethodsRetrospective analysis of 33 MM patients referred to our centre for tandem ASCT/outpatient NMA HSCT between May 2008 and December 2012. Patients were transplanted as part of their front line management (upfront) (n=18) if they had one or more high risk disease features (poor prognosis cytogenetics/FISH abnormalities, elevated LDH, stage III disease or less than a PR following a novel agent-containing induction regimen) or as a ‘deferred' procedure (n=15), if relapsing/progressing after an initial ASCT and maintenance/consolidation. Allo HSCT was undertaken as an ambulatory procedure and conditioned with oral fludarabine 48mg/m2 on days -4 to -2 and 2Gy TBI on day 0 followed by donor stem cell infusion, with a target CD34 dose of 2 x 106/kg and T cell dose of 3 x 108/kg. Sequential peripheral blood monitoring of CD3+ and CD33+ donor-specific chimerism was performed on days 30, 60, 90, 180 and 365 following allo HSCT. Bone marrow samples were collected for MRD analysis using MFC incorporating a CD56/CD19/CD45 panel following CD38/CD138 gating on plasma cells. MRD assessment was performed every 3 months during the first 12 months, 6 monthly during the second year and annually thereafter. ResultsThe median age for the entire cohort (M 19, F 14) was 52 years (range 39-65) and the analysis performed after a median follow up of 719 days (50-1733). All patients were transplanted using matched sibling (20/33) or unrelated donors (13/33). Non-relapse mortality was 0% at 1 year and 6% overall. At the time of analysis, 26 (79%) patients were alive including 15 (45%) in CR. The median PFS for all patients was 2.8 years and although the median OS for the entire cohort has not been reached, the estimated probability of overall survival at 4 years is 67% (95% CI: 38-85%). 29/33 (88%) patients had MRD assessments performed at least once post-allo HSCT and 4 patients progressed within 3 months prior to MRD evaluation. At the first 3 month assessment, 11/29 (38%) were MRD +, 12/29 (41%) were MRD – , results were unavailable in 3/29 (10.5%) and 3 (10.5%) patients had morphological evidence of disease. Patients achieving MRD negativity at 3 months had superior PFS in comparison to those who remained MRD positive (median 2.81 years v 1.02 years; p=0.01) but this has yet to translate into an OS advantage. The MRD + patients transplanted as a deferred procedure (n=6) had a median PFS of less than 6 months (0.47 years), suggesting this subset of patients have a particularly poor outcome, although overall numbers are insufficient to directly compare outcome according to MRD status and transplant timing. 30 (91%) patients achieved FDC (16 and 14 in the upfront and deferred groups respectively) with 2 patients not assessed. The median time to FDC for the entire cohort was 180 days (range 30-730) and there was no significant difference according to transplant timing or relationship between FDC and MRD status, GVHD, PFS or PS. ConclusionThe majority of patients undergoing outpatient-based tandem ASCT/NMA allo HSCT for myeloma achieve FDC. MRD status as assessed by MFC at 3 months post-allo HSCT appears to predict PFS and may be a useful early trigger for additional post-allograft therapy, particularly in patients with high risk disease or those transplanted later in their disease course. Disclosures:Spencer:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Thalidomide, Lenalidomide and Pomalidomide Disrupt Epstein-Barr Virus (EBV) Latency: Clinical Implications

IntroductionThalidomide (THAL), and the IMiDs® immunomodulatory agents lenalidomide (LEN), and pomalidomide (POM) are all approved for use in multiple myeloma (MM) either as single agents, or in combination with dexamethasone (DEX). Despite the enhanced efficacy of these novel agents, concern has arisen as to the increased incidence of secondary primary malignancies (SPM). For example, the IFM 2005-002 trial reported cases of lymphoblastic leukemia and Hodgkin's disease (HD) following LEN use (Attal, Lauwers-Cances et al. 2012) in MM patients on maintenance therapy. Also, a recent case report described a MM patient who developed HD who had been treated with salvage therapy containing THAL(Chim, Choi et al. 2013), and two publications reported EBV reactivation in MM patients treated with LEN (Kneppers, van der Holt et al. 2011; Kroger, Zabelina et al. 2013). As HD is causally linked to EBV, this raises the question as to whether the IMiDs reactivate latent EBV infection in normal memory B-cells, and thereby increase the risk of EBV-related malignancies. To this end, we have investigated the ability of the IMiD's to induce reactivation of latently infected B-cell lines. MethodsA panel of latently infected EBV-positive B-cell lines including Burkitt's lymphoma (BL) cells and lymphoblastoid cell lines (LCL) were treated with either LEN, THAL or POM, and the status of the EBV lytic cycle was evaluated using in vitro and in vivo models. ResultsTreatment of BL and LCL cell lines with physiological concentrations of IMiDs (1-5 μM) induced the immediate early gene BZLF1 and the early gene BMRF1. Interestingly, the ability to induce EBV reactivation was in their potency order (i.e. POM>LEN>THAL). The IMiD's also induced lytic cell death, as an LCL carrying a BZLF1-deleted EBV, which is incapable of undergoing a lytic cycle, showed no change in cell viability, compared to wild-type cells which had increased cell death. The addition of the nucleoside analogue ganciclovir (GCV) enhanced the cytotoxic effect of LEN and POM alone in BL cells lines. An in vivo xenograft model of BL demonstrated that the combination of LEN and GCV was highly efficacious at suppressing tumor cell growth, thus confirming the ability of LEN to stimulate the EBV-lytic life cycle. The ability to induce EBV reactivation was directly related to the stimulation of phosphatidylinositol-3 kinase (PI3K) signaling, which was completely blockaded by the PI3K-δ inhibitor, CAL101. The combination of LEN with either, DEX or rituximab, induced increased BMRF1 compared to the LEN alone. ConclusionsThe IMiD class of drugs has a potent ability to reactivate the lytic cycle in B-cells latently infected with EBV. We hypothesize that the IMiD's reactivate latently infected resting memory B cells through enhancing PI3K signaling. This reactivation may be further potentiated when the IMiDs are used in combination with rituximab or DEX, which may simultaneously enhance the EBV lytic cycle and suppress the host immune response. These findings suggest the possibility that immunocompromised patients who receive IMiDs should be monitored for evidence of EBV reactivation. Also, this may suggest a mechanism by which patients may develop EBV-associated SPM, an effect which is similar to the methotrexate induced EBV-positive lymphomas seen in rheumatoid arthritis patients (Feng, Cohen et al. 2004).ReferencesAttal, M., V. Lauwers-Cances, et al. (2012). “Lenalidomide maintenance after stem-cell transplantation for multiple myeloma.” The New England journal of medicine 366(19): 1782-1791.Chim, C. S., P. T. Choi, et al. (2013). “Hodgkin's lymphoma as a second cancer in multiple myeloma never exposed to lenalidomide.” Annals of hematology 92(6): 855-857.Feng, W. H., J. I. Cohen, et al. (2004). “Reactivation of latent Epstein-Barr virus by methotrexate: a potential contributor to methotrexate-associated lymphomas.” Journal of the National Cancer Institute 96(22): 1691-1702.Kneppers, E., B. van der Holt, et al. (2011). “Lenalidomide maintenance after nonmyeloablative allogeneic stem cell transplantation in multiple myeloma is not feasible: results of the HOVON 76 Trial.” Blood 118(9): 2413-2419.Kroger, N., T. Zabelina, et al. (2013). “Toxicity-reduced, myeloablative allograft followed by lenalidomide maintenance as salvage therapy for refractory/relapsed myeloma patients.” Bone marrow transplantation 48(3): 403-407. Disclosures:Orlowski:Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: The Takeda Oncology Company: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Resverlogix: Research Funding; Array Biopharma: Honoraria, Membership on an entity's Board of Directors or advisory committees; Genentech: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees.

Signal One and Two Blockade Are Both Critical for Non-Myeloablative Murine HSCT across a Major Histocompatibility Complex Barrier

Non-myeloablative allogeneic haematopoietic stem cell transplantation (HSCT) is rarely achievable clinically, except where donor cells have selective advantages. Murine non-myeloablative conditioning regimens have limited clinical success, partly through use of clinically unachievable cell doses or strain combinations permitting allograft acceptance using immunosuppression alone. We found that reducing busulfan conditioning in murine syngeneic HSCT, increases bone marrow (BM):blood SDF-1 ratio and total donor cells homing to BM, but reduces the proportion of donor cells engrafting. Despite this, syngeneic engraftment is achievable with non-myeloablative busulfan (25 mg/kg) and higher cell doses induce increased chimerism. Therefore we investigated regimens promoting initial donor cell engraftment in the major histocompatibility complex barrier mismatched CBA to C57BL/6 allo-transplant model. This requires full myeloablation and immunosuppression with non-depleting anti-CD4/CD8 blocking antibodies to achieve engraftment of low cell doses, and rejects with reduced intensity conditioning (≤75 mg/kg busulfan). We compared increased antibody treatment, G-CSF, niche disruption and high cell dose, using reduced intensity busulfan and CD4/8 blockade in this model. Most treatments increased initial donor engraftment, but only addition of co-stimulatory blockade permitted long-term engraftment with reduced intensity or non-myeloablative conditioning, suggesting that signal 1 and 2 T-cell blockade is more important than early BM niche engraftment for transplant success.

Current state of art for transplantation paradigms in peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCLs) are a rare and aggressive lymphoproliferative disorder characterized, with few exception, by poor prognosis. A correct diagnosis is still hampered by the heterogeneity and rarity of disease. Historically, PTCLs were treated like aggressive B-cell lymphoma with anthracycline-based combination chemotherapy with disappointing results. Neither dose intensification nor dose escalation of chemotherapy has been successful in prolonging the survival of PTCL patients. Due to this discouraging scenario, new therapeutic strategies have been tested. A therapeutic program including hematopoietic stem-cell transplantation (SCT) may represent an interesting strategy for high-risk patients. Although no randomized trials are available, autologous SCT may offer a chance of cure in chemosensitive disease. Nonmyeloablative allogeneic SCT has shown a curative potential with limited toxicity, and it is actively being investigated. We will review the role of the current therapeutic approach to PTCL focusing on the most recent advances in SCT.

Deep Vein Thrombosis Following Non-myeloablative Allogeneic Stem Cell Transplantation: Presentation of Three Cases and Literature Review

The incidence of deep vein thrombosis (DVT) after non-myeloablative (NMA) allogeneic stem cell transplantation (allo-SCT) is unknown. In addition, very few studies on the predisposing factors for DVT post SCT have been published. The incidence of DVT among patients that underwent NMA allo-SCT at our hospital was 4.1% (3 of 73) over the course of last 8 years, and to the best of our knowledge this is the first study to report the incidence of DVT following NMA allo-SCT. The present findings show that NMA allo-SCT patients may have multiple risk factors for DVT. Herein we present 3 cases of DVT following NMA allo-SCT and a literature review. Conflict of interest:None declared.

Different changes of serum cytokines following HLA-identical and HLA haploidentical non-myeloablative allogeneic hematopoietic stem cell transplantation

This study was aimed to investigate the expression difference of serum cytokines in 20 patients receiving HLA-identical nonmyeloablative allogeneic hematopoietic stem cell transplantation (iNAHSCT) and HLA-haploidentical nonmyeloablative allogeneic hematopoietic stem cell transplantation (hiNAHSCT). IL-2, IL-4, IL-6, IL-10, TNF-α, γ-IFN and IL-17 were detected by flow cytometric bead array before and on week 1, 2, 4 after transplantation respectively. The results showed that the IL-2 level was found to be up-regulated at week 1 and 2 after transplantation in iNAHSCT group and in hiNAHSCT group respectively, but there was no difference between these two groups (P > 0.05). The γ-IFN levels was up-regulated at week 4 after transplantation in above-mentioned two groups, but no difference was found between these two groups. The IL-4 level increased at week 2 and 1 after transplantation in iNAHSCT and hiNAHCT groups respectively, but the IL-4 level in iNAHSCT group was higher than that in hiNAHSCT group. The IL-6 level rose at week 1 and 2 after transplant in above mentioned groups respectively, and reached to peak level at week 4 after transplantation, but IL-6 level in hiNAHSCT was higher than that in iNAHSCT group (P < 0.02). The IL-10 level was up-regulated at week 1 and 2 in iNAHSCT and hiNAHSCT groups respectively, but the IL-10 level in iNAHSC was higher than that in hiNAHSCT group. The TNF-α level was up-regulated at week 1 in hiNAHSCT group, but at week 2 in iNAHSCT group after transplantation. The TNF-α level in hiNHASCT group was higher than that in iNAHSCT group (P < 0.01). The IL-17 level was up-regulated at week 1 and week 4 after transplantation in hiNAHSCT and iNAHSCT groups respectively, the IL-17 level in hiNAHSCT group was high as compared with that in iNAHSCT group. It is concluded that the serum cytokine levels are obviously up-regulated in iNAHSCT and hiNHASCT groups, and reach to peak level at week 4 after transplantation. The IL-6, TNF-α and IL-17 level up-regulated significantly in hiNAHSCT group, but the IL-4 and IL-10 level up-regulated significantly in iNAHSCT.

In vivo protection of activated Tyr22‐dihydrofolate reductase gene‐modified canine T lymphocytes from methotrexate

Nonmyeloablative allogeneic hematopoietic stem cell (HSC) transplantation can cure malignant and nonmalignant diseases affecting the hematopoietic system, such as severe combined immunodeficiencies, aplastic anemia and hemoglobinopathies. Although nonmyeloablative is favored over myeloablative transplantation for many patients, graft rejection remains problematic. One strategy for decreasing rejection is to protect donor activated T cells in the graft from methotrexate (MTX) by genetically modifying the cells to express MTX-resistant dihydrofolate reductase (Tyr22-DHFR), leaving the immunosuppressive effects of MTX to act solely on activated host T lymphocytes, shifting the balance to favor allogeneic engraftment. To evaluate MTX resistance of Tyr22-DHFR(+) T lymphocytes in vivo, we transplanted dogs with autologous CD34(+) cells modified with yellow fluorescent protein (YFP) and DHFR-green fluorescent protein (GFP) lentivirus vectors. Dogs were then treated with a standard MTX regimen days 1, 3, 6 and 11) following immune activation with a foreign antigen as a surrogate assay to mimic early transplantation. DHFR-GFP(+) gene marking was maintained in CD3(+) CD25(+) and CD4(+) T lymphocytes after MTX treatment, whereas the level of T lymphocytes that expressed only a fluorescent reporter (YFP(+) ) decreased. These data show that Tyr22-DHFR expression protects T lymphocytes from MTX toxicity in dogs, highlighting a clinically relevant application for preserving donor T lymphocytes during post-transplantation immunosuppression. The findings of the present study have implications for the clinical translation of MTX-resistant T cells to facilitate engraftment of allogeneic cells following nonmyeloablative conditioning and to minimize the risk of rejection. In summary, Tyr22-DHFR expression in T lymphocytes provides chemoprotection from MTX-mediated elimination in the context of immune activation in vivo.

O-014 Azacitidine versus best supportive care before non-myeloablative allogeneic stem cell transplantation for MDS: A study by the SFGM-TC

O-014 Azacitidine versus best supportive care before non-myeloablative allogeneic stem cell transplantation for MDS: A study by the SFGM-TC

Haploidentical nonmyeloablative allogeneic peripheral blood stem cell transplantation for treatment of refractory or relapsed leukemia: long-term follow-up

To observe the therapeutic effect and major complications of haploidentical nonmyeloablative allogeneic peripheral blood stem cell transplantation (NST) for refractory or relapsed leukemia. The results of 30 patients, including 14 cases of acute myeloid leukemia (AML), 11 cases of acute lymphoblastic leukemia (ALL), 5 case of chronic myelogenous leukemia (CML) (accelerated and blastic phase) with refractory or relapsed leukemia (RF/RL) who underwent haploidentical NST from August 2000 to April 2009 were analyzed. The conditioning regimen consisted of fludarabine (flu), antithymocyte globulin (ATG), cyclophosphamide (CTX), total body irradiation (TBI) and cytarabine (Ara-C) or myleran (Bu). Graft-versus-host disease (GVHD) prevention programmes consisted of Cyclosporine (CsA), mycophenolate mofetil (MMF), CD25 monoclonal antibody combined with mesenchymal stem cells (MSC). Twenty six cases of patients were full donor engraftment and 4 cases mixed chimerism into full donor chimerism. The average duration of neutrophil >0.5×10⁸/L after NST was 11 (9-16) days, and platelet >20×10⁸/L 17 (12-60) days. Upon follow-up of 16 to 120 months, 12-month transplant-related mortality (TRM) was 46.7%, acute Ⅱ-Ⅳgraft-versus-host disease (aGVHD) incidence was 40.0%. The probability of 3-year disease relapse, EFS and overall survival (OS) rates were 16.7%, 46.2% and 50.0% respectively. Haploidentical NST could improve OS and EFS of refractory or relapsed leukemia and reducce TRM to some extent.

Acute colonic pseudo-obstruction following allogeneic stem cell transplantation successfully treated by neostigmine

Acute colonic pseudo-obstruction (ACPO), also known as Ogilvie's syndrome, is a rare clinical syndrome of massive large bowel dilatation without mechanical obstruction, which may cause significant morbidity and mortality. Treatment focuses on decompressing a severely dilated colon. The proposed theory that this severe ileus results from an imbalance in the autonomous regulation of colonic movement supports the rationale for using neostigmine, a reversible acetylcholinesterase inhibitor, in patients who failed conservative care. Although gastrointestinal complications are frequent following allogeneic stem cell transplantation (SCT), the incidence of ACPO in a transplant setting is unknown and, if not vigilant, this adynamic ileus can be underestimated. We describe the case of a patient with myelodysplastic syndrome undergoing non-myeloablative allogeneic SCT from a partially human leukocyte antigen-mismatched sibling donor, and whose clinical course was complicated by ACPO in the early post-engraftment period. The ileus was not associated with gut graft-versus-host disease or infectious colitis. After 3 days of conservative care, intravenous neostigmine (2 mg/day) was administered for 3 consecutive days. Symptoms and radiologic findings began to improve 72 hours after the initial injection of neostigmine, and complete response without any associated complications was achieved within a week. Thus, neostigmine can be a safe medical therapy with successful outcome for patients who develop ACPO following allogeneic SCT.

Improved Clinical Outcomes in Chronic Lymphocytic Leukemia Patients with 17p Deletion (CLL 17p-) Who Are Able to Proceed with a Nonmyeloablative Allogeneic Stem Cell Transplantation (NST) Following an Initial Consultation with the Transplant Service: A Single Centre Experience

Abstract 1977▪▪This icon denotes a clinically relevant abstract Background:17p- is a principle predictor of poor outcome in CLL patients after conventional chemotherapy. Since 2007, the MD Anderson Leukemia Service initiated a concerted effort to refer CLL17p- patients for NST consideration at the time of their first presentation. While studies have suggested NST to be able to overcome this adverse prognostic impact, the applicability of this NST for the majority of patients and potential selection bias remains unclear. Purpose:We retrospectively reviewed outcomes of CLL 17p- patients to determine how often patients underwent NST(NST+), the reasons they did not (NST-), and whether any characteristics, including survival, differed between the two groups. Patients and Methods:52 CLL17p- patients were referred to the Transplant Service between 2007–2010. Wilcoxon rank-sum and Fisher’s exact tests were used to compare clinical variables of interest by NST status. Kaplan-Meier survival curves and Cox proportional hazards regression were used to estimate survival. Results:20 (38%) of the 52 referred patients underwent NST. The remaining 32 patients (62%) were not transplanted for the following reasons: death due to pre-NST salvage treatment/or disease related complications (n=15, 47%); physician/patient preference in chemosensitive patients (n=10, 31%); lost to follow up (n=4, 12.5%); no available donors (n=3, 9%). 21(40%) were previously untreated, while 31 (60%) had received a median of 4 lines of treatments at other centers. No significant difference was observed in age at referral between the two groups (median 54 years for NST+ vs 60 years for NST-, p=0.2). In addition, no significant differences were observed for several other patient characteristics, including gender, beta2-microglobulin, associated myelodysplasia, number of prior treatments, ZAP-70+, unmutated heavy chain, or presence of additional cytogenetic abnormalities. Although more patients in the NST- group had elevated lactate dehydrogenase level than in the NST+ group (84% vs 45%, p= 0.0049), there was no significant difference observed in documented Richter’s (25% vs 15%, p=0.5). Median follow up from the time of diagnosis and referral was 5.3 years (range 0.7–22 years) and 1.5 years (range 0.1–4.8 years) respectively. The 2-year post-referral PFS rates were 50% and 8% in the NST+ and NST- groups, respectively. 2-year post-referral OS rates were 64% and 25%, respectively (Fig 1A). More importantly, the OS benefit for the NST+ group remained significant even when analysis was restricted to the chemosensitive patients who received NST and those with chemosensitive disease who opted, per patient or physician preference, not to receive NST. The 2-year OS rates for the two groups were 88% and 43%, respectively (Fig 1B). Treatment-related mortality in the NST+ group was 21% at 1-year. Significant univariate determinants of PFS following NST included refractory disease status (p=0.043), number of prior chemotherapies (0.045), and lymph node size >5 cm (p=0.010) at the time of transplant. Lymph node size >5 cm (p=0.031), number of prior therapies (p=0.019), age at transplant (p=0.047), beta-2 microglobulin >4 mg/L (p=0.016), and CD34+ infused (p=0.022) were significant predictors of OS. There was a strong correlation between beta-2 microglobulin level and lymph node size (Spearman rho=0.68, p=0.0018). Multivariate analysis could not be performed due to the sample size. Conclusions:Our study demonstrates that for CLL 17p- patients, allogeneic NST has been associated with a superior outcome to conventional chemotherapy even amongst patients with chemosensitive disease. Our findings provide rationale for consideration of NST in the upfront setting for this subset of patients. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Lenalidomide and Low Dose Dexamethasone As First Line Therapy for Newly Diagnosed Patients with Primary Plasma Cell Leukemia

AbstractAbstract 729 Introduction:The prognosis of primary plasma cell leukemia (PPCL) remains poor. The “novel agents” have recently shown promising results in PPCL patients in case reports or small retrospective series. Here we describe the first prospective, multicenter, phase II clinical trial of PPCL, where lenalidomide in combination with low dose dexamethasone (Ld) was tested as initial therapy in newly diagnosed patients fulfilling the IMWG diagnostic criteria of PPCL. Patients and methods:Ld regimen consisted of lenalidomide 25 mg/d for 21 days and oral dexamethasone 40 mg on days 1, 8, 15, and 22 for each 28-day cycle. After 4 cycles, responding patients not eligible for stem cell transplantation (SCT) continued until 8 cycles of full-dose Ld, followed by a maintenance dose of single agent lenalidomide equal to 10 mg/d on days 1–21 of each 28-day cycle. Patients responding after 4 cycles and eligible for SCT proceeded according to the treatment centre’s transplant policy. Patients not responding after 4 cycles or progressing during this treatment were considered off-study. Appropriate dose reductions (in particular for patients with reduced renal function at baseline), double contraception methods and anti-thrombotic/anti-infective prophylaxis were recommended. The primary end-point was early response rate according to IMWG uniform response criteria. Secondary end-points were PFS, OS, feasibility and efficacy of SCT, safety. Results:According to the Simon optimal two-stage adaptive design, twenty-three patients were enrolled in between March 2009 and May 2011. The male/female ratio was 1.1, and median age was 60 years (range 44–80). The median absolute number and percentage of circulating plasma cells were 4.280/μl (range 1.500–114.660) and 34% (range 21–90) respectively. Fifteen patients (65.2%) had abnormal renal function at presentation. Twenty-one patients (91.3%) were tested by FISH analysis and cytogenetic abnormalities were detected in all of them, del13q being the most frequently found (16 patients). Seventeen patients showed multiple chromosomal lesions. Involvement of chromosome 14 was observed in 18 patients, three of whom showed t(4;14). Chromosome 1q gain and del17p were detected in 10 and 7 patients, respectively. In the intention-to-treat (ITT) population, overall response rate (ORR) after at least one Ld cycle was 73.9% (17/23), with 8 patients (34.7%) achieving partial remission (PR), 5 (21.7%) very good PR (VGPR), 3 (13%) complete response (CR), and 1(4.3%) near CR (nCR) (VGPR or better: 39%). In the efficacy-evaluable (EE) population, 14 out of 15 patients who received the initially planned 4 Ld cycles (65.2% of the ITT population) responded (ORR 93.3%), achieving 5 PR (33.3%), 5 VGPR (33.3%), 1 near-CR (6.6%) and 3 CR (20%) (VGPR or better: 59.9%). The maintenance phase was reached and safely performed in 4 responding patients not eligible for SCT, 3 of whom relapsed after 2, 8 and 22 months, respectively. After Ld induction therapy, 8 patients received single (n. 4) or double (n. 4) autologous SCT (ASCT); another patient underwent a sequence of ASCT followed by non-myeloablative allogeneic SCT (AlloSCT). Six eligible patients did not receive ASCT frontline, due to initial Ld failure or adverse events; three of them underwent single ASCT (n. 2) or tandem ASCT/non-myeloablative AlloSCT (n. 1) after a bortezomib-based salvage therapy, achieving 2 CR and 1 PR. After a median follow-up of 23 months, median OS and PFS in ITT population were not reached and 22 months, respectively. All transplanted patients remained alive, although three of them relapsed and started salvage treatments; OS was 12 months in the 11 patients who did not receive ASCT (p < 0.001). The correspondent figures for PFS were 29 and 16 months, respectively (p < 0.01). Considering ITT population, multivariate analyses showed that SCT was positively correlated to both OS and PFS. There were 17 episodes of grade 3/4 non hematological toxicity, which occurred in 13 patients (5 infections, 3 renal, 3 metabolic, 2 gastro-intestinal, 2 skin, 1 fatigue, 1 thromboembolic), causing early interruption of Ld treatment in 4 patients. Grade 3/4 hematological toxicity (mainly neutropenia) occurred in 11 patients (47.8%). Conclusions:Ld may be a feasible and effective initial therapeutic option for PPCL, particularly in patients who receive ASCT after a short course of induction treatment. Disclosures:Musto:Celgene: Honoraria, Research Funding. Off Label Use: Lenalidomide as first line therapy of plasma cell leukemia. Petrucci:Celgene: Honoraria. Cascavilla:Celgene: Honoraria. Di Raimondo:Celgene: Honoraria. Caravita:Celgene: Honoraria. Morabito:Celgene: Honoraria. Offidani:Celgene: Honoraria. Bringhen:Celgene: Honoraria. Boccadoro:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Palumbo:Celgene: Consultancy, Honoraria.

Sirolimus, Tacrolimus and Low-Dose Methotrexate Based Graft-Versus-Host Disease (GVHD) Prophylaxis After Non-Ablative or Reduced Intensity Conditioning in Related and Unrelated Donor Allogeneic Stem Cell Transplantation: Decreased Severe Early aGVHD but Persistence of Late Acute Gvhd

AbstractAbstract 4194 Background:The morbidity and mortality associated with acute and chronic graft-versus-host disease (GVHD) remain significant after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Encouraging results have been reported with the combination of sirolimus, tacrolimus, and low-dose methotrexate after non-myeloablative allogeneic peripheral blood stem cell transplantation (PBSCT) (Alyea EP et al, Biol Blood Marrow Transplant 2008). We conducted a retrospective analysis of 74 patients with hematologic malignancies who underwent a non-myeloablative (NMA) or reduced intensity (RIC) allo-HSCT using sirolimus, tacrolimus, and low-dose methotrexate for GVHD prophylaxis. Methods:Between April 2008 and June 2011, 74 patients (M/F: 45/29), median age 51 years (range: 23–69) were transplanted for non-Hodgkin’s lymphoma (63%), chronic lymphocytic leukemia/small lymphocytic lymphoma (20%), Hodgkin lymphoma (12%) and acute lymphoblastic leukemia or myelodysplasia (3%). At transplantation, 36 patients (49%) were in complete remission and 38 patients (51%) had chemotherapy sensitive active disease. Conditioning regimen was NMA in 59 patients and RIC in 15 patients. Donors were HLA-matched related (MRD, n = 30, 41%), matched unrelated (MUD, n = 37, 50%) or 9/10 HLA-mismatched unrelated (MMUD, n = 7). All patients received peripheral blood mobilized grafts. GVHD prophylaxis consisted of sirolimus and tacrolimus that were started on day -3 and doses were adjusted to maintain target serum trough levels of 3–12 ng/mL and 5–10 ng/mL, respectively, followed by methotrexate 5 mg/m2 on days +1, 3, 6. Tapering of sirolimus and tacrolimus began at day 60 in the absence of GVHD or relapse, with the goal of complete discontinuation of immunosuppressants by 6 months or earlier if patients were not in CR at transplant. Recipients of MUD (31 of 37) or MMUD (7 of 7) grafts were given 2 doses of anti-thymocyte globulin (ATG) on days −3, and −2. Forty-eight patients with CD20+ malignancies (65%) received rituximab at day -8 and +21, 28, 35, 42. Acute GVHD (aGVHD) was scored by IBMT Severity Index and chronic GVHD (cGVHD) based on NIH consensus criteria. Results:The cumulative incidence of Grade B-D and C-D classic aGVHD at day +100 were 14.9% and 2.7%, respectively. The cumulative incidence of aGVHD at 1-year was 31.1 % for grade B-D and 5.4 % for grade C-D, due to late-onset Grade B-D and Grade C-D aGVHD rates of 16.2% and 2.7%, respectively. The incidence of cGVHD at 1 and 2 years was 15% and 28%, respectively. The use of peri-transplant rituximab did not affect the incidence of Grade B-D aGVHD (p=0.55) or cGVHD (p=0.94). There was no difference in the incidence of Grade B-D aGVHD at day 100 between ATG (13.9%) and no ATG (15.8%) cohorts. There was a trend towards a modestly higher 2-year incidence of cGVHD in patients who did not receive ATG, despite the fact that these were predominantly recipients of MRD (37% vs. 21% in ATG cohort, p=0.12). Two patients (2.7%) developed thrombotic microangiopathy and 4 patients (5.4%) had renal toxicity, requiring modification of the immunosuppressant treatment. No sinusoidal obstructive sydrome was reported. To date, 15 patients have died; causes of death include disease recurrence (n=9) and GVHD (n=6). The cumulative incidence of non-relapse mortality and relapse at 1 year were 4% and 27%, respectively. The 1-year relapse rate in the ATG and no ATG cohorts was 11% and 28%, respectively (p=0.10). With a median follow up 2.6 (range: 0.8–3.9) years, progression-free and overall survival at 2 years were 64 % and 77 %, respectively. Conclusions:As previously reported this GVHD prophylaxis regimen is safe and effective, providing lower rates of acute GVHD compared to historical data. The incidence of chronic GVHD by NIH criteria was low due to an increase in late-onset acute GVHD. Rituximab therapy did not affect the incidence of acute and chronic GVHD. The addition of ATG in MUD and MMUD recipients resulted in a trend toward lower rates of chronic GVHD with no increase in the rate of relapse. Future strategies will need to focus on decreasing the incidence of late onset acute and chronic GVHD without increasing the risk of relapse. Disclosures:No relevant conflicts of interest to declare.

The combination of sirolimus plus tacrolimus improves outcome after reduced-intensity conditioning, unrelated donor hematopoietic stem cell transplantation compared with cyclosporine plus mycofenolate

Different types of graft-versus-host disease prophylaxis have been proposed in the setting of reduced intensity and non-myeloablative allogeneic stem cell transplantation. An alternative combination with sirolimus and tacrolimus has recently been tested although comparative studies against the classical combination of a calcineurin inhibitor and mycophenolate mofetil or methotrexate are lacking. We describe the results of a prospective, multicenter trial using sirolimus + tacrolimus as immunoprophylaxis, and compare this approach with our previous experience using cyclosporine + mycophenolate in the setting of unrelated donor transplantation setting after reduced-intensity conditioning. Forty-five patients received cyclosporine + mycophenolate between 2002 and mid-2007, while the subsequent 50 patients, who were transplanted from late 2007, were given sirolimus + tacrolimus. No significant differences were observed in terms of hematopoietic recovery or acute graft-versus-host disease overall, although gastrointestinal acute graft-versus-host disease grade ≥ 2 was more common in the cyclosporine + mycophenolate group (55% versus 21%, respectively, P=0.003). The 1-year cumulative incidence of chronic graft-versus-host disease was 50% versus 90% for the patients treated with the sirolimus- versus cyclosporine-based regimen, respectively (P<0.001), while the incidence of extensive chronic disease was 27% versus 49%, respectively (P=0.043). The 2-year non-relapse mortality rate was 18% versus 38% for patients receiving the sirolimus- versus the cyclosporine-based regimen, respectively (P=0.02). The event-free survival and overall survival at 2 years were 53% versus 29% (P=0.028) and 70% versus 45% (P=0.018) among patients receiving the sirolimus- versus the cyclosporine-based regimen, respectively. In conclusion, in the setting of reduced intensity transplantation from an unrelated donor, promising results can be achieved with the combination of sirolimus + tacrolimus, due to a lower risk of chronic graft-versus-host disease and non-relapse mortality, which translates into better event-free and overall survival rates, in comparison with those achieved with cyclosporine + mycophenolate.

Mini Test Dose of Intravenous Busulfan (Busulfex®) in Allogeneic Non-Myeloablative Stem Cell Transplantation, Followed by Liquid Chromatography Tandem-Mass Spectrometry

Busulfan (Bu) has been used for almost 3 decades in the conditioning of hematopoietic stem cell transplant. Bu has a very diverse gastrointestinal absorption which in association with its emetic effect in high doses makes inter- and intra-individual oral bioavailability and thus systemic exposure very variable and difficult to predict (1, 2, 3). If the systemic exposure is below the therapeutic window there is an increased risk of lack of engraftment (4) and, in chronic myelogenous leukemia (CML) patients, disease relapse (5), while overexposure results in an increased incidence of high-dose related toxicities like hepatic veno-occlusive disease (6, 7). It is important to note that “busulfan concentration-response relationships are regimen-, age- and disease-dependent”, as emphasized by McCune et al (8). Therapeutic dose monitoring (TDM) gained an important role in the setting of oral Bu dose as it became clear that the level of systemic exposure influenced the toxicity, engraftment and relapse rates. To give an idea of the importance of TDM, a test dose prior to starting the conditioning regimen with home-administered oral Bu in 153 patients evidenced that as many as 68% of them would have drug exposures out of the therapeutic window (900–1,500 μM·min) with the standard dose of 1mg/kg of ideal body weight every 6 hours (9). An intravenous (i.v.) formulation was developed to overcome these issues and avoid the utilization of TDM, However, in a series of 6 studies using intravenous Bu in adults, 72 to 91% of the patients achieved the target AUC without dose changes, while 10 to 82% of children achieved it in a series of 5 studies with the intravenous drug (10). Clearly, a need for TDM even when i.v. is used still persists. Many different strategies using single or repeated sampling in different points of the therapy were proposed to improve TDM results (10). However, since TDM can only be useful if Bu determinations are timely delivered and many transplant centers do not have a facility to perform Bu determination, new approaches using pharmacokinetic analysis of a sub-therapeutic test dose administered a few days earlier to predict the ideal dose were proposed. In one such study, 7 patients received a test dose of 0.8 mg/kg, followed by 0.8 mg/kg/dose every 6 hours for 15 doses (11). Bu concentrations were obtained and mean drug clearance was determined after the test, first and 13th doses. The utilization of a test dose demonstrated bioequivalence ( 20% variability). However, when the same 0.8 mg/kg test dose assay was compared to the intravenous Bu in continuous infusion for 90 hours in other 7 patients, they showed similar clearances (12). The next step was to examine the ability of the test dose clearance to base the calculation of the 90 hour continuous infusion dose (13). All 4 patients tested had AUCs within the desired range and no adjustments were required after 18 hours. More recently, Beri et al. (14) used a 0.8 mg/kg i.v. test dose (1/4 of the standard daily dose). Without the test dose, 23% of the 17 patients would have fallen below and 12% above the therapeutic range. With the test dose, no patients had a sub-therapeutic AUC and only 12% had an AUC above the therapeutic window. In this work, in order to further reduce the unnecessary exposure and adverse effects of the test dose process, we investigated bioequivalence of a very low sub-therapeutic test dose (1/10 of the standard daily dose) of i.v. Bu (Busulfex®). For this purpose we developed a sensitive and fast liquid chromatography tandem-mass spectrometry (LC-MS/MS) method which allowed us to measure Bu in a wide concentration range required in the study.

Rituximab in combination with high-dose dexamethasone for the treatment of relapsed/refractory chronic lymphocytic leukemia

BackgroundHigh-dose methylprednisolone is active in treatment of relapsed/refractory chronic lymphocytic leukemia (CLL) but infectious toxicity is serious. The aim of this project was to retrospectively assess efficacy and safety of high-dose dexamethasone combined with rituximab (R–dex) in this setting. Patients and methodsWe treated 54 patients (pts) with relapsed/refractory CLL using R–dex regimen at two tertiary centers. Two schedules of rituximab were used (not randomized – based on the choice of the center): group 1, rituximab 500mg/m2day 1, 8, 15, 22 (375mg/m2 in 1st dose) every 4 weeks (n=29); group 2, 500mg/m2day 1 (375mg/m2 in 1st cycle) repeated every 3 weeks (n=25). The target dose of dexamethasone was 40mg on days 1–4 and 10–13 or 15–18. Rai III/IV stages were present in 82%, unmutated IgVH genes in 82%, del 11q in 38% and del 17p in 19% pts; 46% had bulky lymph nodes; 82% were pretreated with fludarabine and 29% with alemtuzumab. ResultsOverall response rate/complete remissions were 62/21% (Group 1) and 72/4% (Group 2). In three patients, R–dex was successfully used for debulking before nonmyeloablative allogeneic stem cell transplantation. R–dex was particularly effective in improvement of anemia and thrombocytopenia (p=0.0055 and p=0.0036); B-symptoms resolved after treatment in 11/17 pts. Hematological toxicity was mild. Serious infections occurred in 32% pts. At the median follow-up of 9 and 10 months, median progression-free survival was 6 months in Group 1 and 6.9 months in Group 2 (p=ns); median overall survival was 14.1 months in Group 1 vs. not reached in Group 2 (p=ns). ConclusionsR–dex appears to be an active and feasible treatment for relapsed/refractory CLL. Infectious toxicity remains an important issue. Further investigation of this regimen in larger studies appears fully warranted.