Allogeneic PBSCT Research Articles

Low-Dose ATG Has the Same Risk of CMV Reactivation after Allogeneic PBSCT As Ptcy, but Letemovir Is Effective in Preventing CMV Reactivation

[Introduction] Allogeneic peripheral blood stem cell transplantation (allo-PBSCT) is a curative treatment for hematological malignancies but has a risk of a chronic graft-versus-host disease (GVHD) compared to other donor sources. Post-transplant cyclophosphamide (PTCY) has been spread rapidly worldwide from HLA haploidentical-SCT (Haplo-SCT) to HLA matched-SCT. Although PTCY was theoretically thought to preserve non-alloreactive T cells which can contribute to fight infection, recent studies showed that PTCY was associated with the increased incidence of cytomegalovirus (CMV) infection. Letermovir (LTV), a novel anti-CMV agent, was useful for the prevention of CMV reactivation after SCT including Haplo-SCT using PTCY. On the other hand, low-dose antithymocyte globulin (ATG) is an alternative and useful option for GVHD prophylaxis in allo-PBSCT and often used in Japan. However, the risk of post-transplant CMV reactivation and the protective effect of LTV when using low-dose ATG remain to be elucidated. [Methods] We retrospectively analyzed 222 recipients who received allo-PBSCT using PTCY or low-dose ATG at Hokkaido University Hospital from January 2013 to July 2021. Of the 121 patients who underwent PBSCT with PTCY, 69 (all patients underwent Haplo-PBSCT) were without LTV prophylaxis and 52 (34 patients, Haplo-PBSCT) were with LTV. On the other hand, of the 101 patients who underwent PBSCT with low-dose ATG, 66 (12 patients, Haplo-PBSCT) were without LTV and 35 (2 patients, Haplo-PBSCT) were with LTV. LTV was administered on the day 0 at a dosage of 480 mg daily. All patients were monitored for CMV reactivation by using the anti-CMV pp65 monoclonal antibody HRP-C7 assay at least weekly from neutrophil engraftment to discharge and after discharge monthly until day 180 after SCT. CMV reactivation was defined as the start of CMV preemptive therapy, generally initiated when there are 2 or more CMV antigen positive cells per 50000 white blood cells. Moreover, CMV disease was defined by organ dysfunction attributable to CMV. [Results] Baseline characteristics of the patients are summarized in Table 1. Although more patients in ATG group compared to PTCY group received myeloablative conditioning regimen significantly, there was no significant difference between the groups in terms of sex, age, underlying disease, disease risk at SCT, and CMV serostatus. GVHD prophylaxis in PTCY consisted of CY (40-50 mg/kg on day 3 and 4), tacrolimus (from day 5), and mycophenolate mofetil (from day 5), whereas that in ATG consisted of ATG at a total dose of 2-3 mg/kg around day -2, tacrolimus (from day -1) and short-term methotrexate. LTV prophylaxis significantly reduced the cumulative incidence of CMV reactivation at 180 days after SCT in PTCY group (69.6% without LTV vs. 22.4% with LTV, p<0.001) and ATG group (62.6% without LTV vs. 18.9% with LTV, p<0.001; Figure 1.). Importantly, although CMV disease were occurred in 2 patients in PTCY (1 gastritis and 1 retinitis) and 8 focuses in 7 patients (3 pneumoniae, 3 enteritis, 1 retinitis, and 1 glossitis) in ATG without LTV prophylaxis, none of the patients receiving LTV developed CMV disease in both group. Moreover, LTV did not affect overall survival, the cumulative incidence of non-relapse mortality, relapse, acute GVHD, and engraftment of neutrophil and platelet. Interestingly, the cases of early CMV reactivation within 100 days after SCT under LTV prophylaxis was significantly more frequent in ATG than in PTCY (p=0.0345). [Conclusion] CMV reactivation occurred with similar frequency after allo-PBSCT with low-dose ATG as after that with PTCY. LTV was effective for prevention of CMV reactivation in both GVHD prophylaxis methods. CMV breakthrough reactivation may be likely to occur in PBSCT with low-dose ATG compared to that with PTCY even under LTV prophylaxis, and careful CMV monitoring may be required.

High Risk of Recurrence of Malignancy Noted in Four-day rATG Regimen After Allogeneic PBSCT From Matched Sibling Donors

Hitherto, the optimal timing of rabbit anti-thymocyte globulin (rATG) in matched sibling donor peripheral blood stem cell transplantation (MSD-PBSCT) remains to be elucidated. We wanted to evaluate the effect of a new timing strategy of rATG in MSD-PBSCT patients on transplantation outcomes. In this prospective single-arm phase 2 clinical trial, 45 consecutive MSD-PBSCT patients were enrolled from February 1, 2019, to January 31, 2021. The rATG was administered intravenously at a total dose of 5 mg/kg from day −5 to day −2 before graft infusion (4d-ATG group). Thirty-seven MSD-PBSCT patients receiving rATG at the same total dose of 5 mg/kg from day −5 to day −4 before graft infusion from December 1, 2014, to January 31, 2019 served as historical control (2d-ATG group). No graft failure occurred in either group. In the 4d-ATG group, median timing to neutrophil and platelet engraftment was 12 days. The cumulative incidences (CI) of grade 2-4 and grade 3-4 acute graft-versus-host disease (GVHD) at day 100 were 37.8% and 4.4%. The 2-year CIs of severe chronic GVHD and extensive chronic GVHD were 2.2% and 9.6%. The rates of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) reactivation at day 180 were 24.4% and 37.8%, respectively. No patients died of non-relapse causes. Twenty-one patients relapsed at a median of 203 days after transplantation, and the 2-year cumulative incidence of relapse (CIR) was 51.4%. The 2-year probabilities of overall survival (OS), disease-free survival (DFS), and GVHD-free and relapse-free survival (GRFS) were 72.4%, 48.6%, and 40.8%, respectively. There were no significant differences between the 4d-ATG group and 2d-ATG group with regard to timing of neutrophil and platelet engraftment, incidences of CMV reactivation, EBV reactivation, acute GVHD, chronic GVHD, probabilities of OS, and GRFS. The 2-year CIR was significantly increased, and the 2-year DFS was significantly reduced in 4d-ATG group compared with the control group (CIR: 51.4% versus 13.5%, P < .001; DFS: 48.6% versus 75.7%, P = .014). High CIR and worse DFS were noted in MSD-PBSCT receiving 4d-ATG regimen compared with historical control (2d-ATG regimen). Inappropriate rATG timing may increase the risk of relapse after MSD-PBSCT in patients with hematologic malignancies.© 2023 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Brachial Plexopathy Following High-Dose Melphalan and Autologous Peripheral Blood Stem Cell Transplantation for AL Amyloidosis

Brachial plexopathy (also known as neuralgic amyotrophy or Parsonage-Turner syndrome) is a rare, self-limited condition characterized by bilateral or unilateral shoulder pain followed by weakness. The pathogenesis is unknown, but is believed to be an immune-mediated disorder that is treated conservatively with analgesics and physical therapy (PT). It has been described following viral infections, surgeries, and immunosuppression. There has never been a reported case following high dose melphalan and stem cell transplantation (HDM/SCT) for immunoglobulin light chain (AL) amyloidosis.Here we report two cases of brachial plexopathy following HDM/SCT for AL amyloidosis. These cases were prospectively identified from a population of 42 patients who underwent HDM/SCT at Boston Medical Center between January 2014 and June 2017.The first patient was a 68-year-old woman with AL amyloidosis with renal involvement with a lambda clonal plasma cell dyscrasia. She was diagnosed with AL amyloidosis three months prior to HDM/SCT. She had no history of peripheral neuropathy or other neurologic disorder. Neutrophil engraftment post-SCT occurred on day +9. On day +12, she developed acute onset bilateral shoulder pain and weakness, left greater than right. Neurologic evaluation at the time was notable for 4/5 strength in the left deltoid, triceps, and biceps muscles. Sensation to pinprick was decreased on the dorsum of the left hand. Deep tendon reflexes were normal. These deficits were consistent with C5-8 motor and sensory dysfunction. Magnetic resonance imaging (MRI) of the cervical spine and brachial plexus and electromyography/nerve conduction study were consistent with bilateral brachial plexopathy. Doppler ultrasounds of the upper extremities were negative for deep venous thrombosis. Lyme disease and West Nile virus testing were negative. She began treatment with PT and her symptoms completely resolved at two years following HDM/SCT.The second patient was a 58-year-old woman with Waldenström's macroglobulinemia (WM) and associated AL amyloidosis with renal involvement with an underlying lambda clonal plasma cell dyscrasia. She was initially diagnosed with WM eight years prior to her diagnosis of AL amyloidosis. She received eight cycles of rituximab, cyclophosphamide, vincristine, and prednisone for treatment of WM, and then four cycles of rituximab, bortezomib, and dexamethasone after diagnosis of AL amyloidosis. She then underwent HDM/SCT. She had a history of lower extremity peripheral neuropathy secondary to prior treatments, but had no other neurologic symptoms. Neutrophil engraftment occurred on day +10 post-SCT. On day +13, she developed acute onset left shoulder pain and weakness. MRI of the cervical spine and left brachial plexus was consistent with brachial plexopathy. Her symptoms completely resolved by one year post-SCT with PT.These two cases of brachial plexopathy following HDM/SCT are, to our knowledge, the first reported cases in association with AL amyloidosis. Previously, a handful of cases of brachial plexopathy with similar time courses have been described after both autologous and allogeneic PBSCT in association with multiple myeloma, non-Hodgkin's lymphoma, myelodysplastic syndrome, diffuse large B-cell lymphoma, and multiple sclerosis.1-3 An autoimmune process has been postulated, especially given the known phenomenon of immune dysregulation following SCT with immune reconstitution. Direct trauma was not a contributing factor in these cases, and both patients had an internal jugular tunneled venous catheter on the right side. We conclude that brachial plexopathy is an uncommon, but potential early complication of HDM/SCT for AL amyloidosis that should be considered in patients with new onset shoulder pain or weakness. PT may be beneficial to patients with this self-limited disorder.

A Prospective Phase II Clinical Trial of CD26/Dipeptidyl Peptidase (DPP)-IV Inhibition for Prevention of Acute Graft Versus Host Disease (aGVHD) Following Myeloablative Allogeneic Peripheral Blood Stem Cell (PBSC) Transplantation.

<h3>Introduction</h3> DPP-IV is a homodimeric type II transmembrane receptor identical to the leucocyte surface antigen CD26. The interaction of CD26/DPP-IV on T cells with its ligand caveolin-1 on antigen-presenting cells (APC) enhances T cell activation, proliferation, and cytokine production. It also upregulates CD86 on APC resulting in co-stimulation. In a xenograft mouse model, reducing CD26 expression by a monoclonal antibody prevented aGVHD and preserved graft-versus-tumor effects (Hatano et al. <i>BJH</i> 2013). In a pilot trial testing sitagliptin for enhancement of cord blood engraftment, we observed a lower than expected rate of aGVHD (Farag et al. <i>Stem Cell Dev</i> 2013) and hypothesized that CD26/DPP-IV inhibition with sitagliptin may prevent aGVHD following allogeneic PBSC transplants. <h3>Objective</h3> Conduct a prospective phase II trial to test if sitagliptin can reduce the rate of grade II-IV aGVHD by day +100 following myeloablative allogeneic PBSC transplants (ClinicalTrials.gov, NCT02683525). The primary endpoint was grade II-IV aGVHD by day +100. <h3>Methods</h3> Patients received thiotepa (15 mg/kg) and cyclophosphamide (120 mg/kg), followed by G-CSF mobilized PBSC from matched related (6/6 HLA match) or unrelated (10/10 HLA match) donors. Sitagliptin (600 mg q12 hours) was given on days -1 to day +14, together with tacrolimus and sirolimus through day +100, then tapering until day +180. In a Simon two-stage design, <8 of a total of 36 patients developing grade II-IV aGVHD by day +100 would demonstrate a reduction of aGVHD from a historical rate of 30% to <15% with 80% power and type 1 error = 0.1. <h3>Results</h3> Thirty-six (17 M; 19 F) patients of median age 46 (20-59) years were enrolled. Patients had AML (n=19), ALL (n=9), MDS (n=4), and CML (n=4). Transplants were from matched related (13 patients) or unrelated (23 patients) donors. Acute GVHD occurred in 2 of 36 patients by day +100 (1 grade II; 1 grade IV), for cumulative incidences of 5.6% (95% confidence interval [CI], 0% - 13.2%) and 2.8% (95% CI, 0% - 8.2%) for grade II-IV aGVHD and grade III-IV aGVHD at day +100, respectively (Fig 1). An additional patient developed late-onset grade II aGVHD at day +140 following abrupt stopping of immunosuppression on day +100 for low donor chimerism in absence of relapse. Significant toxicities though day +30 included grades III-IV mucositis (n=15), acute kidney injury (4 with high tacrolimus levels, 1 sepsis), viral reactivation/infection (4 CMV, 2 BK, 1 EBV, 1 HHV6), and passenger lymphocyte syndrome (n=2). Non-relapse mortality was 0% at 12 months. With median follow-up of 699 (118-1312) days, the relapse-free survival was 77.2% (95% CI, 63.2% - 91.1%) and overall survival was 94.3% (95% CI, 86.7% - 100%) at 12 months (Fig 2a-b). <h3>Conclusion</h3> CD26/DPP-IV inhibition with sitagliptin is well-tolerated and significantly reduced the rate of aGVHD by day +100 in patients undergoing myeloablative allogeneic PBSCT transplantation.

Efficacy of G-CSF Primed DLI Using Cells Reserved at the Time of Harvest in Patients with Hematologic Malignancies Who Lately Relapsed after Allogeneic PBSCT

IntroductionThere is no standard therapeutic approach for the relapse after allogeneic hematopoietic cell transplantation (allo-HCT). The aim of this paper is to confirm the role of granulocyte colony-stimulating factor (G-CSF) primed donor lymphocyte infusion (DLI) according to the timing of relapse after allo-HCT with limited CD34+ cell dose (<6x106/kg)MethodsOne hundred ten patients who had relapsed after allo-HCT at Kyungpook National University Hospital from November 2001 to December 2014, including 40 patients who received DLI from cryopreserved cells derived from the original G-CSF primed graft, were retrospectively reviewed. The patients were classified into early relapse or late relapse group by the median time of relapse after transplant.ResultsThe median age at transplant was 38.5 years (range, 17-67 years) and male was 69 patients (62.2%). Primary diseases for allo-HCT included AML/MDS (n=63, 57.3%), ALL (n=32, 29.1%), CML (n=8, 7.3%), and NHL (n=7, 6.4%). Fifty four patients (49.1%) were in CR1 (complete remission), 16 (14.5%) in CR2, and 40 (36.4%) in relapsed and refractory status at the time of HCT. Sixty nine patients (62.2%) received myeloablative conditioning regimen. The median dose of CD34+ cells was 5.06x106/kg (range, 1~20.6x106/kg). Ninety nine percent of patients achieved the neutrophil recovery (> 500x103/mm3 for 3 days) at a median time of 13 days (range 9-24 days). The median time from HCT to relapse was 139 days (range, 21~1801 days). The median relapse free survival (RFS) since HCT was not significantly different according to the dose of CD34+ cells: median 147 days (range, 122-171) and 157 days (range, 87-227) in CD34+ < 6x106/kg and > 6x106/kg, respectively (p=0.249). The median overall survival (OS) since HCT was not significantly different according to the dose of CD34+ cells: median 324 days (range, 272-375) and 262 days (range, 235-288) in CD34+ < 5.06x106/kg and > 5.06x106/kg, respectively (p=0.554).The incidence of chronic GVHD was more frequent in higher CD34+ group (32.9% vs. 48.2%, P=0.042). After relapse, 57 patients (51.8%) were treated with salvage chemotherapy, 13 patients (11.8%) with second allo-HCT, and 40 patients (36.4%) with G-CSF primed DLI. The median number of CD3+T cell was 2.95x107/kg (range, 0.1~5.43x107/kg). Fourteen patients (23.6%) achieved DLI-induced CR, 20 patients progressed, and 6 patients were not evaluable for response. DLI-induced acute GVHD was observed in 25 patients (62.5%) and chronic GVHD developed in 4 patients (10%). The 1-year overall survival (OS) since relapse was not significantly different according to the use of DLI in early relapse group (11.7 +/- 5.3% and 10.0 +/- 6.7%, p=0.663), but in late relapse group, significantly higher in DLI than non-DLI (43.3 +/- 11.3% and 17.1 +/- 6.9%, p=0.021). The patients treated with DLI showed significantly higher RFS in late relapse group (286 days vs. 165 days, p=0.004). The incidence of DLI-induced GVHD did not differ between two groups.ConclusionsG-CSF primed DLI after allo-HCT with limited CD34+ cell dose can be feasible and effective option in terms of response, donor convenience and its cost. In the late relapse group, it may replace the second transplantation for the patients with hematologic malignancies lately relapsed after first allo-HCT. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

T- Cell Depleted Peripheral Blood Stem Cell (TCD-PBSC) Transplants Secure Consistent Engraftment with Low Risk of Acute or Chronic Gvhd and Favorable Disease Free Survival (DFS) and Overall Survival (OS) for Pediatric Patients (

Higher cGVHD, TRM and treatment failure following sibling donor unmanipulated allogeneic PBSCT compared to BMT in children and adolescents has been reported by the IBMTR (Eapen M et al, J Clin Oncol, 2004). To determine the effect of T cell depletion (TCD) of PBSC on outcome for pediatric patients with AML or MDS, we reviewed our results with 49 patients (pts) with AML-1CR (n=18), AML-CR2 (n=11), MDS (n=10) and tAML/MDS (n=8/2) following allogeneic TCD-PBSCT transplanted between June 2003 and January 2015. Median age in this cohort was 13.9yrs (range 1.9 - 20.4) with 27 males and 19pts CMV seropositive at time of PBSCT. Donors were related HLA identical (14siblings, 1uncle), unrelated HLA 10/10 matched (n=14) or unrelated HLA mismatched (n=20: 9/10 n=12: 8/10 n=8). Cytoreduction consisted of a HFTBI containing regimen (n=14) with thiotepa and cyclophosphamide (n=12) or thiotepa and fludarabine (n=2). Alternatively, 35 pts received chemotherapy alone: BU/MEL/FLU (n=31) or other (n=4). ATG provided graft rejection prophylaxis for 43 pts either pre (n=37) or post (n=6) infusion. Six young pts with sibling donors did not receive ATG. No pt received additional GVHD prophylaxis. PBSC were CD34+ selected using ISOLEX 300i Magnetic Cell Selection System, followed by sheep erythrocyte rosetting (n=25) or CD34+ selected with Miltenyi CliniMACS device (n=24). The median CD34+ cells/Kg was 10.5x106 (range 3.3 - 33.4x106) and CD3+ cells/kg was 2.4x103 (range 0 - 29x103).All pts engrafted neutrophils and platelets at a median of 11 days (range 9 - 14 days) and 26 days (range 13 - 182 days), respectively. 42pts had platelet recovery by day 40. One patient who had late graft failure (GF) at 3.5 mos engrafted with a subsequent unmanipulated PBSCT. Seven pts developed Grade II or III aGVHD of skin or GI. No pt had Gr IV aGVHD. Six pts responded to treatment. Only 1pt developed limited cGVHD of the skin. No pt who was CMV seronegative developed CMV viremia. 7 of 19 CMV seropositive pts developed CMV viremia. Nine pts received rituximab for EBV viremia. No pt died of CMV disease or EBV-LPD. Five pts received defibrotide for treatment of VOD. Table 1N1o GF2o GFaGVHD (Gr 2-3)cGVHD (limited)CMV-CTLEBV-CTLRelapseAlive in CR p2nd SCT for GF/rel3 yrs DFS3 yr OSEntire Cohort4901(2%)6(12%)1 (2%)1(2%)1(2%)11(22%)5(4rel,1GF)72.3%87.7%AML-CR11800210043(3rel)75.6%94.4AML-CR2110020114056.0%66.7MDS1001000022(1GF,1rel)78.8%100%tAML/MDS100020001080.0%88.9%With a median follow-up of 36.3 mos the DFS and OS at for the entire cohort at 3 yrs is 72.3% and 87.7%, respectively. Although the DFS for pts with AML-CR1 is 75.6%, 3 of 4 pts are in CR2 post a second BMT for OS of 94.4%. The 4 pts with AML-CR2 who relapsed died of disease. In this series of 49 pts, 6pts died of disease, 1 pt died of aGVHD and 1 pt (Down Syndrome) died of MOF (VOD). Thus, in young pts (< 21 yrs) TCD-PBSCT is associated with low risk of acute and chronic disease, no increment in relapse and a highly favorable DFS and OS. The data support the inclusion of pediatric pts in BMT CTN 1301 trial (NCT02345850): a Randomized, Multi-Center, Phase III Trial of Calcineurin Inhibitor-Free Interventions for Prevention of Graft-versus-Host Disease. DisclosuresKernan:Gentium S.p.A.: Research Funding. Hasan:Atara Biotherapeutics: Research Funding. O'Reilly:Atara Biotherapeutics: Research Funding.

Early Clinical Experience of aAPC Activated NK-DLI Following Allogeneic PBSCT in Pediatric Solid Tumor Patients.

AbstractAbstract 3013 Background:Allogeneic Hematopoietic Stem Cell Transplant (alloHSCT) is effective in some hematologic malignancies and studies of alloHSCT for ultra high-risk pediatric solid tumors have shown some promise. Preclinical data demonstrates that activated NK cells readily kill pediatric solid tumors and leukemias, large numbers of activated NK cells can be generated ex vivo using artificial APCs (aAPCs) and the post-transplant period may be favorable for expansion and survival of adoptively transferred NK cells. Methods:We initiated a Phase I trial to assess feasibility and toxicity of escalating doses of donor-derived activated NK cell donor lymphocyte infusions (NK-DLI) on days 7 and 35 days following HLA-matched T cell depleted PBSCT in children and young adults with ultra-high risk solid tumors and leukemias. Donors underwent a single apheresis for filgrastim mobilized PBSC. The product was T cell depleted and CD34 and CD56 selected prior to cryopreservation, and the CD56+ fraction was cultured for 9–11 days with a K562 based aAPC expressing 4-1BBL and IL-15Ra plus rhIL-15 to generate the NK-DLI. NK-DLI consistently expressed high levels of natural cytotoxicity receptors NKp44 and NKp46 and mediated potent cytotoxicity ex vivo. T cell addback to the CD34 selected graft was performed to administer a T cell dose of 0.8–1.4 × 10e4 T cells/kg. Except for two pilot patients where NK-DLI was infused following engraftment, NK-DLI were administered ∼Day 7 and 35 post-transplant. Patients received a reduced intensity preparative regimen (fludarabine 30 mg/m2 and cyclophosphamide, 1200 mg/m2 on days –6 to -3; and melphalan 100 mg/m2 on day -2), and no prophylactic immunosuppression. Results:Seven patients with sarcomas were transplanted with NK-DLI infusion (1×10e5 CD56+ cells/kg/dose). Engraftment was brisk (median platelet recovery at 8d and neutrophil recovery at 9d). Patients had full donor myeloid chimerism by day 14 and all but one had >80% lymphoid chimerism by day 28. Patient #1 received NK-DLI on day +24 following alloHSCT and experienced aGVHD within 24 hours of NK-DLI with bullous skin rash and voluminous diarrhea. Prior to infusion the patient had what appeared to be a viral rash and fevers (skin biopsy negative for GVHD), but in retrospect likely GVHD, which was exacerbated by NK-DLI. Patient #2 received NK-DLI on Day +15 with no adverse effects. Subsequent patients enrolled onto cohort 1 with planned NK-DLI at days 7 and 35 (+7). Two patients developed aGVHD (rash and diarrhea), one with a cytokine-type reaction (fevers, hypotension) within 48 hours of NK-DLI infusion and one with aGVHD starting 21 days post NK-DLI. All 3 patients with matched unrelated donors experienced aGVHD after NK-DLI, whereas the 5 patients with matched sibling donors had no apparent adverse reactions nor GVHD. Persistence/engraftment of infused NK-DLI cannot be definitively determined, however, mean NK cell counts measured pre-alloHSCT and day +28 are 165/mm3 and 668/mm3 in the present cohort (n=6) compared to 149/mm3 and 395/mm3 in a historical alloHSCT population that did not receive NK-DLI (n=24). Antitumor effects via PET imaging were observed in patients with measurable disease and those without disease at the time of transplant have remained NED. Conclusions:Ex-vivo, aAPC expanded NK-DLIs do not interfere with stem cell engraftment but may contribute to or induce aGVHD, particularly in patients with matched, unrelated donors. Preliminary results suggest that aAPC NK-DLI expand in vivo and mediate antitumor effects following allogeneic PBSCT.Table:PatientAge/GenderDiseaseNK Cell DoseDay of NK Infusion (post-HSCT)DonorLikely NK Related ToxicitiesAnti-tumor EffectsStatusPre-HSCT NK CountPost-HSCT/NK1 Count (day 28-35)134 y FDSRCT1 × 105/kgDay 24MUDGrade IV GVHDPET and CT responseDoD-day + 190861883233 y MEwing's1 × 105/kgDay 14MSDNonePET responseDoD-day + 17122257322 y MDSRCT1 × 105/kgDay 9MUDFever, Grade II GVHDCRNED298762416 y MEwing's1 × 105/kgDay 8, Day 33MUDFever, Grade III GVHDRemains NEDNED179180524 y MDSRCT1 × 105/kgDay 8, Day 35MSDNonePR/CRMRD/NED119428618 y MARMS1 × 105/kgDay 8, Day 36MSDNoneRemains NEDNED85698714 y MEwing's1 × 105/kgtoo earlyMSDtoo earlytoo earlyNEDMEAN165668 Disclosures:No relevant conflicts of interest to declare.

Thrombopoietic Agonists Show Efficacy in ITP Related to Allogeneic Stem Cell Transplantation,

Abstract 3292▪▪This icon denotes a clinically relevant abstractPatients with refractory immune thrombocytopenia (ITP) have limited therapeutic options, with morbidity and mortality as often from infection as from bleeding. Thrombopoietin (TPO) mimetics allow an increase in the platelet count without causing immunosuppression. These agents may be especially useful in patients with secondary forms of ITP. We report three patients treated with TPO agonists for ITP post Allogeneic Stem Cell Transplants (SCT).Patient 1: MC, 37yrs, developed refractory ITP after a myeloablative allogeneic SCT for Accelerated Phase CML. He was unresponsive to standard treatments (figure 1a), requiring platelet transfusions 3x weekly for active bleeding. He started Eltrombopag 50mg/day in July 2009. He had a clinically significant increase in his platelet count (supported count increased to 40) so platelet transfusions were reduced to 2x weekly. Eltrombopag was increased to 75mg in November with a subsequent platelet increase to 90 and by December 2009 he was platelet independent, maintaining a platelet count 90–120 on Eltrombopag alone, 25mg/day, 5 days week. [Display omitted] Patient 2: BT, 4yrs(12kg), underwent a myeloablative allogeneic PBSCT in September 2009 for JIA/HLH. She became thrombocytopenic in June 2010, presumed to be ITP. She had no response to prednisolone or rituximab and a only a minimal response to IVIG; requiring platelets 1x weekly. She started Eltrombopag 7mg OD in November 2010, escalated to 12mg by February 2011. This had a synergistic effect with IVIG and she became platelet independent after one month of Eltrombopag and IVIG, maintaining platelet counts 50–200 (figure1b).Patient 3: MG, 62yrs, underwent a reduced intensity allogeneic SCT in March 2010 for stage 3 Sezary syndrome. Post SCT he developed pancytopenia associated with EBV reactivation. He received daily GCSF, regular blood and weekly platelet transfusions. In July he developed GI bleeding from HSV colitis and his platelet transfusion requirements increased to alternate days. In October 2010 he was started on Romiplostim 250mcg, increased to 350mcg weekly, erythropoetin and GCSF. He had a clinically significant rise in his platelet counts and a reduction in his platelet requirements to 1x weekly within weeks of starting romiplostim. By December he was platelet independent, with counts persistently over 50, and romiplostim was stopped (figure1c).All three patients remain in remission at the time of submission of the abstract.Immune cytopenias are well-recognised post myeloablative allografts occurring in 5–37% of SCT recipients. The occurrence of ITP in SCT recipients has been reported, in which GVHD or the production of anti-platelet alloantibodies of recipient origin was considered to play major roles. Although small numbers, these case studies show efficacy of thrombopoietic agents (recently licensed for use in chronic ITP) in patients with thrombocytopenia post SCT refractory to standard therapies, with an early reduction and subsequent cessation in platelet transfusion requirements in all three patients. The lack of immune suppression with these agents may be particularly relevant in patients post SCT, in whom immune reconstitution is vital not only in preventing infections, but also in preventing rejection of the graft and in establishing a graft versus leukaemia effect. Given that TPO receptors are present on haematopoietic stem cells at all stages of development and that TPO provides a growth factor for stem cells, the use of these agents in patients treated for leukaemia requires caution. There was no evidence of progression of disease in these patients and TPO agents were only required for a period of time (patient 3 is off therapy and the others only receive minimal doses). Formal evaluation of these agents in allogeneic SCT is warranted. Disclosures:Cooper:GSK: Honoraria; Amgen: Honoraria.

Induction of graft versus malignancy effect after unrelated allogeneic PBSCT using donor lymphocyte infusions derived from frozen aliquots of the original graft

To evaluate safety and efficacy of donor lymphocyte infusions (DLI), derived from frozen aliquots of the original G-CSF-stimulated graft after allogeneic PBSCT from unrelated donors, data of 121 patients with hematological malignancies treated with DLIs were retrospectively analyzed. Indications for PBSCT were AML/myelodysplastic syndrome (n=63/8), ALL (n=17), lymphoma (n=13), multiple myeloma (n=10) and myeloproliferative syndrome (n=10). Reasons for DLI were hematological relapse (n=81), molecular and/or cytogenetic relapse (n=5), mixed chimerism (n=22) and prophylactic DLI in high-risk patients (n=13). DLIs were well tolerated with no acute adverse reactions. DLI-induced acute-type GvHD (aGvHD) was observed in 19 patients and chronic-type GvHD (cGvHD) developed in 14 patients. Three patients died of GvHD complications. DLI induced CR, complete chimerism or PR in 34 patients; 24 patients had stable disease, 50 patients progressed and 13 patients were not evaluable for response. Objective response was more obvious for molecular relapse (5/5) or mixed chimerism (14/22) compared with hematological relapse (13/81). Median survival after first DLI was 10.4 months (95% confidence interval: 4.4-26.0). Cryopreserved G-CSF-stimulated DLI, derived from allogeneic grafts are safe and immunoreactive, and can be applied early in case of mixed chimerism and molecular or cytogenetic relapse.

Successful Haploidentical Stemcell Transplantation In a Patient with Fanconi Anemia and AML.

AbstractAbstract 4586Allogeneic hematopoetic transplantation is the only curative treatment in patients with fanconi anemia indicated as soon transfusion dependency occurs and a matched family or unrelated donor is available. Overall survival for matched or nearly (5/6) matched unrelated donor transplantation improved since the introduction of fludarabine-based conditioning regimens from 30% to 53%. Transplantation after malignant transformation, in heavily pretransfused patients or from alternative donors is associated with a dismal outcome. We report the case of a 7 year old girl with fanconi anemia who developed AML-M4 (monosomy 7 and gain on chromosome 3) with 24% peripheral blasts during donor search for HCT. Remission was acchieved with a mild chemotherapeutic regimen consisting of a single dose of intravenous (300mg/m2) and intrathecal (40mg) cytarabine and daily oral thioguanine (cumulative dose: 930mg/m2). 4 weeks after diagnosis of AML, the girl was transferred for allogeneic PBSCT (CD3/19 depleted) from an unrelated mismatched (7/10) donor. Conditioning regimen consisted of Fludarabine, Busulfex, ATG and OKT-3. Unfortunately, mixed chimerism was observed and on day +21 graft rejection was diagnosed. The patient underwent a second PBSCT from the same donor after conditioning with Fludarabine, Alemtuzumab and Cyclophosphamide and 12 days later received a stem-cell-boost due to poor hematological regeneration. Prolonged aplasia under treatment with G-CSF was suspicious for non-engraftment. The indication for a third PBSCT with her haploidentical father as donor was set. Conditioning in the aplastic patient with elevated autologous T-Lymphocytes consisted of ATG only for 3 days. Full engraftment was achieved on day +11. CMV-reactivation was effectively treated with a combination therapy of valganciclovir and foscavir. One year after the third PBSCT, the patient is in continuing morphologic remission with normal Cytogenetics and complete donor chimerism. Mild Graft vs. Host Disease (Grade I, Skin) dissolved after short term therapy with Prednison. Still she suffers under minor restrictions in her every day life. We demonstrate here the case of a CMV-positive patient with fanconi anemia and AML, polytransfused (27 red-cell-packs and 94 platelet-transfusions) who survived mismatched PBSCT of her CMV-positive father after two failed PBSCT from an alternative 7/10-mismatched donor. To our knowledge this is the first patient with fanconi anemia and AML, successfully transplanted from an haploidentical donor. Disclosures:No relevant conflicts of interest to declare.

Reduction of infection-related mortality after allogeneic PBSCT from HLA-identical siblings: longitudinal analysis from 1994 to 2008 at a single institution

Infection-related mortality (IRM) is responsible for a major proportion of all cases of non-relapse mortality (NRM) after allogeneic PBSCT (alloPBSCT). We analyzed 580 consecutive adults who received a first alloPBSCT from an HLA-identical sibling from 1994 to 2008 at a single institution to describe the severe infections and report the incidence, causes and risk factors for IRM and NRM. Both IRM and NRM decreased with time; within the period of 1994-2000, the 2-year incidence of IRM and NRM was 22 and 31%, respectively, vs 11 and 16% within the period of 2001-2008 (P<0.05 for both comparisons). In multivariate analysis, the variables that increased IRM were within the earlier period of 1994-2000 (P<0.01), poor performance status (P<0.01), grade II-IV acute GVHD (P<0.001) and invasive fungal infection (IFI) (P<0.001) or CMV disease (P<0.001) after transplant. With respect to NRM, earlier time period was also identified as a risk factor (P<0.001), as well as IFIs (P<0.001) and CMV disease (P<0.001). The intensity of the conditioning regimen had no effect on IRM and NRM. These results showed a significant reduction in IRM and NRM over a period of 15 years. The development of IFIs and CMV disease continue to have an impact on NRM.

Liver function tests and absolute lymphocyte count at day +100 are predictive factors for extensive and severe chronic graft‐versus‐host disease after allogeneic peripheral blood stem cell transplant

Chronic graft-versus-host disease (cGVHD) is the major late complication after allogeneic hematopoietic stem cell transplant [1,2]. In this article, we have analyzed the value of noninvasive day +100 tests as predictors of severe cGVHD development in 165 patients undergoing allogeneic peripheral blood stem cell transplant (allo-PBSCT) from a matched related donor. The cumulative incidence of overall, extensive, and severe cGVHD was 67, 56, and 23%, respectively, among patients surviving >100 days after transplant. In univariate analysis, patients displaying an abnormal liver function tests (LFTs) (total bilirubin, alkaline phosphatase, and GGT > 2 times above the upper normal limit) and a low absolute lymphocyte count (ALC) (<percentile 25: 0.750 x 10 9 /L) had a significantly higher risk of overall, extensive, and severe cGVHD. In multivariate analysis, the combination of abnormal LFT and low ALC allowed to predict the risk of overall [HR = 3.35 (95% CI: 1.65-6.83), P < 0.001], extensive [HR = 4.22 (95% CI: 1.96-9.12), P < 0.001], and severe cGVHD [HR = 8.17 (95% CI: 2.55-26.17), P = 0.002]. Our findings show that an increased total bilirubin, alkaline phosphatase, and GGT levels together with the ALC at day +100 are noninvasive, simple, fast, and efficient predictors of severe cGVHD development after allogeneic PBSCT.

Pentostatin and Alemtuzumab: An Immunosuppressive Nonmyeloablative Preparative Regimen for Allogeneic Peripheral Blood Stem Cell Transplantation (PBSCT).

Abstract 4312 IntroductionCurrent nonmyeloablative and reduced-intensity preparative regimens for allogeneic (allo) PBSCT are associated with significant myelosuppression and neutropenia. We evaluated a novel, purely immunosuppressive preparative regimen of continuous-infusion pentostatin (PEN) plus alemtuzumab (ALEM) in patients (pts) undergoing related and unrelated allo PBSCT for high-risk hematological malignancies. Patients and Methods12 pts (median age, 58.5 yr; range, 23-69 yr; 7 male, 5 female) with high-risk, relapsed or refractory acute myelogenous leukemia (AML; 5 pts), Hodgkin's disease (HD; 2 pts), multiple myeloma (MM; 2 pts), chronic lymphocytic leukemia (CLL; 1 pt), low-grade non-Hodgkin's lymphoma (NHL; 1 pt) or myelodysplastic syndrome (1 pt) were enrolled on this study; 6 pts had failed previous autologous PBSCT. The median interval between most recent conventional chemotherapy and allo PBSCT was 3.5 months (range, 1.5-19.5 months). Pts received continuous-infusion PEN (12 mg/m2 over 72 hr, days -8 through -6) and ALEM (20 mg/day, days -5 through -1) followed by allo PBSCT from 8/8 HLA-matched related (3 pts) or unrelated (9 pts) donors. All pts received single-agent cyclosporine (CSP) for prophylaxis of acute graft-versus-host disease (GVHD). ResultsMedian cell doses were 5.45 (range, 1.86-7.90) x 106 CD34+ cells/kg and 2.71 (range, 1.40-4.46) x 108 CD3+ cells/kg. Ten pts had asymptomatic transient elevations of AST and ALT (CTCAE grade 2-3) between days -6 and +21. No pts developed mucositis. Median duration of post-PBSCT hospitalization was 7 days (range, 3-62 days). The median nadir of the absolute neutrophil count (ANC) was 1.24 (range, 0.55–5.11) x 109/L at day +15, and the median nadir of the platelet count was 70 (range, 16-244) x 109/L at day -1. In contrast, the median nadir of the absolute lymphocyte count (ALC) was zero (range, 0-0.72) x 109/L at day -4. ALC remained low at day +28 (median, 0.09 × 109/L; range, 0.05-0.91 × 109/L) and increased by day +100 to a median of 0.34 × 109/L (range, 0.23-2.63 × 109/L). One pt developed grade 2 acute GVHD at day +21. No pts developed chronic GVHD. Evaluation of chimerism in bone marrow at day +28 showed that 3 pts had zero donor DNA and 9 pts had a median of 17% (range, 3-68%) donor DNA. At day +100, 2 of 8 evaluable pts (one with zero and one with 13% donor DNA at day +28) had zero donor DNA in bone marrow, and 6 pts had a median of 64% (range, 21.3-100%) donor DNA. Cumulative actuarial probability of sustained engraftment (defined as at least 50% donor DNA in bone marrow) is 53.4%. Doses of infused CD34+ cells or CD3+ cells were not statistically significantly different in pts with or without allogeneic engraftment (P=0.34, Mann-Whitney test). Three pts had asymptomatic reactivation of cytomegalovirus at 5, 11, and 35 days, respectively, after allo PBSCT. Two pts developed disseminated toxoplasmosis, which was fatal in 1 pt. One pt developed Mucor sinusitis and died with Enterococcus sepsis. One pt developed nonfatal Nocardia pneumonitis and sepsis at 175 days after allo PBSCT. Relapses occurred in 5 pts (1 AML, 1 CLL, 1 HD, 2 MM) at a median of 106 days (range, 28-360 days) after allo PBSCT; 1 of these pts had had engraftment failure and autologous hematopoietic recovery. The actuarial probability of relapse is 56.4%. Seven pts died at a median of 60 days (range, 44-347 days) after allo PBSCT: 1 relapse of HD, 2 infection (1 toxoplasmosis, 1 Enterococcus sepsis), 1 pulmonary hemorrhage with multiorgan failure, and 3 refractory acute GVHD that occurred following treatment of relapse with donor lymphocyte infusion (1 pt), withdrawal of CSP (1 pt) or second allo PBSCT (1 pt). Four subjects (2 AML, 1 HD, 1 NHL) are alive in remission at a median of 513 days (range, 267-787 days) after allo PBSCT. Actuarial probabilities of overall survival and event-free survival are 40.0% and 31.3%, respectively. ConclusionsA preparative regimen of continuous-infusion PEN plus ALEM can allow engraftment of HLA-matched allogeneic PBSCs without significant myelosuppression. However, engraftment failure is greater after this purely immunosuppressive regimen than with standard nonmyeloablative or reduced-intensity regimens. Relapsed or refractory disease at time of allo PBSCT, the absence of cytoreduction with this preparative regimen, and potentially a decrease in graft-versus-tumor effect as a result of profound and prolonged immunosuppression are factors that contribute to the relapse rate observed in this study. Disclosures:Off Label Use: Pentostatin administered as a continuous infusion according to FDA IND #67,067.

Use of the Propensity Score Matching Method to Reduce Recruitment Bias in Observational Studies: Application to the Estimation of Survival Benefit of Non-Myeloablative Allogeneic Transplantation In Patients with Multiple Myeloma Relapsing after a First Autologous Transplantation.

Despite recent advances in the treatment including Autologous Stem Cell Transplantation (A-PBSCT) and new drugs, Multiple Myeloma (MM) is still an incurable disease and the outcome of relapsing patients is still extremely grim. The use of conventional allogeneic hematopoietic SCT is limited by a high transplantation-related mortality (TRM). Allografting with nonmyeloablative conditioning (NMA-C) has therefore been considered to improve survival. We retrospectively studied a series of 23 consecutive patients with relapsing MM who underwent allogeneic transplantation after NMA-C and compared their outcome with those of patients who relapsed but were not allografted. Owing to these non-randomized available data, there was a need to correct for potential recruitment bias. The propensity score (PS) methodology allows coping with the presence of such a bias (Rosenbaum PR, Rubin DB. The central role of the propensity score in observational studies for causal effects. Biometrika 1983; 70:41–55). The idea was to model, for each patient with MM alive at 6 months after relapse, the probability of receiving NMA-C transplantation, according to a set of baseline characteristics (namely, baseline age, serum beta2 microglobulin level (b2M), and time to progression (TTP) after the first A-PBSCT). This PS was estimated using logistic regression. It was then used to match 1:1 patients with similar propensity to receive allograft, based on nearest neighbor matching using calipers of width 0.2. Data of patients treated in the MAG-95 and MAG-2002 trials were used. Standardized differences in covariates between subjects in the matched sample were computed, with imbalances tested by paired t tests. A random effects model was finally fitted in order to account for the matched nature of the data. 23 patients with MM in first (n=21) or second (n=2) relapse were treated with high dose therapy (melphalan 200 mg/m2 followed by A-PBSCT) preceding allogeneic PBSCT with a 2 Gy TBI NMA-C. Donors were HLA-identical siblings in 13 (56 %) patients. Six patients (26%) had a high b2M (>3 mg/L). Median age at allograft was 50 years (29–59 years). Median follow-up after allograft was 27.4 months (1.8–61.8 months). Post-allograft response was CR in 9 patients, VGPR in 8, PR in 4 and progressive disease (PD) in 2. TRM at one year was 13 % (1 severe GvHD, 2 infections). Two patients died from PD at 2 and 9 months after allograft respectively. Acute GvHD occurred in 19 patients (15 grade I/II, 4 grade III/ IV) and 11 developed chronic GvHD. Among the 10 patients (41.6%) who relapsed with a median of 10,7 months, 6 are alive with a median survival of 38.3 months. So far, 8 patients (34,7%) including 5 in CR and 3 in VGPR are still alive without relapse with a median follow-up of 36.8 months. From the 23 allografted patients, 21 matched pairs were successfully constituted. Expectedly, the distribution of age (mean difference: −0.97, p= 0.54), b2M (p=1.00), and TTP (mean difference: 3.2 months, p= 0.37) were not different between treated by allograft and untreated subjects. Based on these matched pairs, the estimated hazard ratio of death was 0.35 (95% confidence interval: 0.14–0.88, p=0.027) for allografted patients compared with non allografted. In conclusion, the PS is a useful tool for the analysis of observational data. Applied to MM data, it suggests that NMA-C allograft in MM patients in first relapse provides a high and durable response rate with a low TRM. These promising results must be further evaluated in clinical trials.

Adoptive Transfer and Consequential Selective Reconstitution of Streptamer-Selected Cytomegalovirus-Specific CD8+ T Cells Leads to Enduring Virus Clearance in Patients after Allogeneic Stem Cell Transplantation

Background: Cytomegalovirus (CMV) disease constitutes a serious complication after allogeneic peripheral blood stem cell transplantation (allo-PBSCT). For the clearance of CMV, CD8+ T cells are pivotal. Patients after allo-PBSCT with recurrent CMV reactivation usually lack such CMV specific T cells. Conventional antiviral therapy of CMV reactivation characteristically results in myelosuppression and further suppression of CMV specific T cells. Adoptive transfer of CMV specific T cells may help to overcome this problem. A novel technology designated “streptamers” allows the selection of CMVpp65 specific CD8+ T cell up to 98% purity without altering the functional properties of the selected T cells and without requiring cumbersome and time consuming T cell cultures.Materials and Methods: Here, the novel streptamer technology was used for adoptive transfer of CMV specific T cells into two acute leukemia patients with recurrent high CMV antigenemia after allo-PBSCT. Standard peripheral blood mononuclear cell apheresis was performed on the former stem cell donors of two patients with acute leukemia. Isolation of CMV specific donor lymphocytes was performed using a Good Manufacturing Product (GMP)-grade Streptamer selection kit on a CliniMacs™ device. Briefly, MHC-Streptamers (CMVpp65/HLA-B7 for patient 1; CMVpp65/HLA-A2 for patient 2) were labeled with beads overnight to obtain MHC-streptamer-bead complexes. Subsequently CMV specific T-lymphocytes were immunomagnetically labeled by incubating mononuclear cells with MHC-Streptamer-bead complexes. Cells were run on a CliniMacs™ device. The positive fraction was then incubated with biotin to detach the steptamers from the T cells.Results: A single specific donor lymphocyte infusion (sDLI) of 0.4 or 2.2 ×105 CMVpp65 specific T cells per kg body weight was performed in an AML or ALL patient respectively, after allogeneic PBSCT developing a CMVpp65 antigenemia with a maximum of 959 or 716 CMVpp65 positive/500,000 cells and treatment with foscarnet, ganciclovir and valganciclovir. After sDLI, the CMV antigenemia was cleared and remained persistently controlled even after discontinuation of valganciclovir therapy in both patients. No acute or chronic toxic side effect, particularly no aggravation of graft-versus-host disease (GvHD) was observed. A strong and sustained increase of the absolute count of CMV-specific CD8+ T cells in concordance with the increase of CD3+CD8+ T cells up to 440/μl was detected. CMV-specific CD8+ T cells showed no significant expression of CCR7, CD62L or CD107, but stained increasingly positive for CD45RA, indicating a preferential effector T cell phenotype. Results from stimulation experiments of CD3+ T cells with HLA-B7 versus HLA-A2 restricted CMVpp65 derived peptides demonstrate late reconstitution of HLA-A2-restricted CMV-specific T cells, whereas the adoptively transferred HLA-B7-restricted CMV-specific T-cell response augmented very early und was maintained over time.The chimerism analysis of the in vivo expanded CMV-specific CD8+ T cells demonstrated a 100% donor chimerism. T cell receptor excision circle (sjTRECs) analysis revealed a frequency of sjTRECs two logs lower than expected, indicating peripheral expansion rather than thymic proliferation of CMV specific CD8+ T cells. cDNA generated from FACS-purified donor-derived CMV B7 pp65-specific CD8+ T cells was probed with the indicated 5′ Vß14-specific and 3′ CDR3-specific primers for the presence of clonotypic T cells. The respective CDR3 region sequence was identical for both donor T cells and CMVpp65 specific T cells in the patients at different time points after the adoptive T cell transfer, thus clearly indicating that the expanded CMV specific T cell were of clonogenic donor origin.Conclusion: Streptamer technology offers the advantage of selecting CMV specific CD8+ T cells at GMP level for adoptive T cell transfer. Two CMVpp65 specific T cell transfers resulted in a marked increase of CMV-specific CD8+ T cells and induced long-lasting CD8+ T cell responses, which allowed the patients to discontinue toxic antiviral drug therapy without further high level reactivation of CMV.

Azacitidine in the Treatment of Elderly Patients with Acute Myelogenous Leukemia

BACKGROUND: Effective treatment of the elderly patient with acute myelogenous leukemia (AML) remains a challenging task. Elderly patients with AML usually respond poorly to standard induction chemotherapy. Response rates in elderly patients are in the range of 30–50% compared to 80–90% in younger patients. Moreover, prolonged hospitalization with treatment related mortality as high as 30% is typical in this older population. In a prior retrospective analysis done at our institution, azacitidine showed an overall response rate of 60% with limited toxicity when administered to patients older than 55 years of age with AML. We present an interim analysis of the first 8 patients enrolled in our prospective, phase II open label study using single agent azacitidine for elderly patients with AML.METHODS: This is a prospective, phase II open label study using azacitidine in patients ≥ 60 years with AML. Inclusion criteria: Newly diagnosed AML (de novo or secondary, WHO criteria) and ECOG ≤ 2. Promyelocytic (M3) phenotype was excluded. Patients with circulating blast count ≥ 30,000/mcl were treated with hydroxyurea until < 30,000/mcl. Azacitidine was given at a dose of 100 mg/m2 subcutaneously for 5 consecutive days every 28 days until disease progression or significant toxicity. G-CSF was given to patients with neutropenia (ANC < 1000/mcl) during all cycles excluding cycle one.RESULTS: Eight patients have been enrolled to date. The mean age of patients is 74 (range: 64–82 years). The mean baseline ECOG performance score was 1 with a mean during treatment of 1. Mean baseline bone marrow blast count was 53% (range: 21–92%). Overall response rate using the NCI response criteria was 75% (6/8): complete response (CR; n=2; 25%) and partial response (PR; n=4; 50%). The mean number of days on treatment was 117 (range: 4–247 days). The mean number of days hospitalized during therapy was 18 (range: 7–51 days) with the majority of therapy being given in the outpatient setting. The mean overall survival time from diagnosis for all patients was 180 days (range: 23–403). The mean overall survival time for responders was 200 days (range: 36–403). Three patients continue on therapy at 146 (PR), 153 (CR) and 247 (PR) days. Of the other responders, one went on to receive an allogeneic PBSCT, one died at 36 days from complications of a strangulated hernia, and one removed himself from study at 82 days (unconfirmed CR) to receive treatment closer to home. All patients were red blood cell (RBC) transfusion dependent at the start of the therapy. To date, two of the six responders (33%) became independent of RBC transfusion. Four patients were transfusion dependent for platelets at the start of therapy with two being non-responders and two achieving a PR. Non-hematological toxicity was limited to mild injection site skin reaction and fatigue in 63% (5/8) each. No treatment related deaths were observed. The dose and schedule of therapy remained constant in all patients except one who required a 25% dose reduction after cycle 3 due to drug induced marrow suppression.CONCLUSION: This interim analysis suggests that the administration of subcutaneous azacitidine in an accelerated dosing schedule to elderly patients with acute myelogenous leukemia is a feasible and well-tolerated alternative to standard induction chemotherapy.

Plasmacytoid Dendritic Cell Count on Day 28 in HLA-Matched Related Allogeneic Peripheral Blood Stem Cell Transplant Predicts the Incidence of Acute and Chronic GVHD

Dendritic cells (DC) are antigen-presenting cells involved in induction and regulation of immune responses. We investigated the impact of the number of infused and day 28 dendritic cells on the development of acute and chronic GVHD (aGVHD, cGVHD). Monocytoid (MC) and plasmacytoid (PC) dendritic cells were characterized as lin −HLA-DR +CD11c + and lin −HLA-DR +CD123 +, respectively. Sixty-eight consecutive patients who underwent HLA matched related granuloyte-colony stimulating factor (G-CSF) mobilized allogeneic PBSCT, from February 2005 to May 2006, were included in the analysis. Twenty-three patients developed aGVHD (grade II-IV) and 21 patients had cGVHD. On a univariate analysis the day 28 total DC and the day 28 MC and PC dendritic cells as continuous variables were significantly associated with development of aGVHD and cGVHD. Using an ROC plot analysis a cutoff value for total DC = 10.7/μL, MC = 9.7/μL, and PC = 4.5/μL on day 28 gave the highest likelihood ratios for aGVHD (2.7, 2.14, and 3.29, respectively). On a multivariate analysis, a low day 28 PC (≤4.5/μL) together with patient age retained their risk for aGVHD (hazard ratio [HR] = 65.1 and 1.0, P-values .000 and .036, respectively), whereas for cGVHD only a low day 28 PC remained significant (HR = 11.8, P = .008). These results suggest that the PC dendritic cell count in the peripheral blood on day 28 is a strong predictor for development of GVHD in recipients of an allogeneic matched related PBSCT.

Successful treatment of refractory Langerhans cell histiocytosis by allogeneic peripheral blood stem cell transplantation

We describe a six-yr-old boy who exhibited typical signs and symptoms of LCH with EBV-associated hemophagocytic syndrome from the age of 15 months. Multiple courses of conventional chemotherapy achieved only marginal improvement over the ensuring five yr. During this period, this boy experienced recurrent episodes of hemophagocytic syndrome associated with CMV infection. Five yr after the first diagnosis of LCH, the patient was treated with allogeneic PBSCT from his HLA-identical eight-yr-old brother. PBSCT was performed using a TBI-incorporating conditioning regimen comprising TBI, busulfan, and cyclophosphamide. Diabetes insipidus, typically a permanent consequence of LCH, was well controlled by DDAVP therapy. At the time of writing, this boy is alive and well, and had been disease-free for more than two yr after the PBSCT.

Late Onset Eosinophilia (beyond Day 100), Rather Than Early Onset Eosinophilia, Has a Significant Prognostic Impact on Transplant Outcomes after Allogeneic Peripheral Blood Stem Cell Transplantation (PBSCT).

Background: The significance of eosinophilia after allogeneic stem cell transplantation (SCT) is presently unknown. The eosinophil activation pathway involves Th2 cytokines and thus eosinophilia after PBSCT may reflect Th2 pathway activation. Previous data suggest that blood eosinophilia precedes or coincides with the development of acute or chronic graft-verus-host disease (aGVHD or cGVHD). In a recent report, Aisa et al reported that patients with peripheral eosinophilia within 100 days post-SCT had a superior overall survival (OS) and transplant-related mortality (TRM) along with a lower incidence of cGVHD compared to those who did not (Transplant Int 2007). Methods: A retrospective analysis of 237 recipients who received allogeneic PBSC from related donors at PMH was performed (myeloablative:reduced intensity conditioning 162:75). The present study evaluated the impact of early (before day 100: EEo) or late onset (beyond day 100: LEo) eosinophilia (≥0.5x109/L in peripheral blood) on transplant outcomes after allogeneic PBSCT. The patient population included 237 recipients of allogeneic PBSC from related donors (male:female 137:100, median age 51 years-old). Results: Biphasic pattern of eosinophilia with 2 peaks before day 100 and beyond day 100 was observed after PBSCT. The cumulative incidence of early onset eosinophilia was 43% at day 100. EEo was not associated with the development of grade 3–4 aGVHD (p=0.1), but there was a trend in the development of grade 2–4 aGVHD (p=0.053). In univariate analyses, the group with EEo showed favorable OS (p=0.002), TRM (p=0.05) and a lower relapse incidence (p=0.05) compared to those without EEo but did not have improved GVHD-specific survival (GSS). EEo did not predict the grade of aGVHD or response to steroid therapy for aGVHD. EEo was significantly associated with the development of late onset eosinophilia (p=0.000004 by chi-square test, p=0.00007 by McNemar test). The cumulative incidence of LEo was 62% at 2 years with median onset of 1 year after SCT. There was an association with the onset of cutaneous (p=0.001), oral (p=0.04), ocular (p=0.02) or pulmonary cGVHD (p=0.03). In univariate analyses, with median follow-up durations of 773 days (patients with LEo) and 679 days (patients without LEo), significant differences were observed in favor of those with LEo in terms of 3 year OS (86% vs 41%, p=0.00000000005), TRM at 3 years (10% vs 37%, p=0.000003), 3 year relapse rate (11% vs 31%, p=0.00003) and 3-year GSS (90% vs 64%, p=0.00001). In multivariate analyses, the LEo, rather than EEo, was identified as a significant favorable prognostic factor for OS (p=0.000006, hazard ratio [HR] 0.21), TRM (p=0.0006, HR 0.24), relapse incidence (p=0.003, HR 0.28) and GSS (p=0.001, HR 0.26). Conclusion: The late onset eosinophilia (beyond day 100), not EEo, seemed to have an important prognostic implication for outcome after allogeneic PBSCT. Further studies are warranted to validate its prognostic impact on SCT outcomes. Figure 1. Comparisonof overall survival (A) and GVHD-specific survival (B) between patients with and without late onset eosinophilia after allogeneic PBSCT Figure 1. Comparisonof overall survival (A) and GVHD-specific survival (B) between patients with and without late onset eosinophilia after allogeneic PBSCT

The Impact of Transfusion-Dependency on the Outcome of Patients with Myelodysplastic Syndromes (MDS) Receiving Allogeneic Peripheral Blood Stem Cell Transplantation after Myeloablative Conditioning.

Introduction: The majority of MDS patients become red blood cell transfusion-dependent during their clinical course. In fact, the presence or absence as well the extent of red blood cell transfusion-dependency (RBC-TD) has been recently shown to add significant prognostic information for an individual MDS patient treated with supportive care (BSC) only. Given the fact that allogeneic hematopoietic cell transplantation (HCT) is the only curative option for MDS patients, the aim of this study was to elucidate the role of RBC-TD on patient outcome.Methods: We report results of a retrospective multicenter German-Austrian study investigating 100 patients with MDS (RA(RS) n=33, RAEB n=33, RAEB-t n=19, CMMOL n=11, MDS/AML n=4) with either IPPS LOW (n=2), INT-1 (n=31), INT-2 (n=37) or HIGH (n=30) undergoing allogeneic myeloablative conditioning followed by peripheral blood stem cells (PBSC) from related (n=39) or unrelated donors (n=61). The median age of the patients was 50 years (range 18–68).Results: With a median follow-up of 32 months the 2-year overall survival (OS) was 48% for all patients and 64%, 50% and 34% for patients according to IPSS INT-1, INT-2 or HIGH, respectively (p=0.03 for INT-1 vs. HIGH). The 2-year OS of all patients was not different when comparing 68 patients displaying vs. 24 not displaying RBC-TD prior to PBSCT (46% vs. 55%, p=0.67). This holds also true when analyzing INT-1/INT-2 (n=62) as well as HIGH (n=27) patients separately. In a multivariate analysis only FAB classification (p=0.03) but not prior induction chemotherapy (n=18), presence of fibrosis (n=18), IPSS LOW/INT-1 vs. INT-2/HIGH, RBC-TD as well as ferritin level lower or above the median 973 μg/l (range 19–7000) had an impact on OS.Conclusion: These data suggest that the negative prognostic impact of RBC-TD in MDS patients receiving BSC can be overcome by myeloablative allogeneic PBSCT.