ALBERT

Description: Abstract 3540 Historically, allogeneic hematopoietic cell transplantation (HCT) has been offered only to patients with good performance status and below the age of 60. However, the peak incidence of most hematologic malignancies is above 60 years of age. The introduction of reduced intensity conditioning (RIC) regimens enabled successful allogeneic HCT in patients with considerable comorbidities and older than 60 years. The impact of age on outcome of allogeneic HCT in patients ≥60 years has not been evaluated extensively. We retrospectively analyzed 109 consecutive patients (f=43, m=66) aged≥60 who received allogeneic HCT 2000–2010 at our institution. Median age of the patients was 65 years (range, 60–76). Patients were grouped in two cohorts depending on age: group 1 aged 60–65 years (n=60, median age=63) and group 2 aged 66–76 years (n=49, median age=68). Diagnoses were acute leukemia (AML n=65, ALL n=1), myelodysplastic syndrome (n=14), osteomyelofibrosis (n=7), non-Hodgkin lymphoma (n=9), multiple myeloma (n=8), aplastic anemia (n=1), chronic myeloid leukemia (n=2) and chronic lymphatic leukemia (n=2). At time of HCT, 41 of the patients were in complete remission (CR), 68 in partial remission (PR) (group 1: CR 21, PR 39; group 2: CR 20, PR 29) and 18 patients had a preceding HCT, 14 in group 1. Conditioning regimens were grouped in high (TBI/Bu+Cy, n=5, all group 1), intermediate (FLAMSA, Flu/Mel/BCNU, n=28, group 1=11, group 2=17), low (FLU+alkylans, n=48, group 1=32, group 2=16) and minimal (2GyTBI/Flu, n=28, group 1=12, group 2=16) intensity. Intermediate intensity conditioning was particularly used for high risk patients in PR (25/28). 22 patients were transplanted from matched related (MRD), 46 from matched unrelated (MUD) and 41 from mismatched unrelated donors (MMUD). Kaplan-Meier-estimated 3-year overall survival (OS) was 45% for all patients, 32% for group 1 and 62%, for group 2, respectively (p=0.02), with more patients with high risk constellation in group 1. 3-year OS for patients transplanted with MUD was 57%, with MMUD 46% vs. with MRD 0% (p=0.01). Non-relapse-mortality was 28% for all patients, 40% in group 1 and 12% in group 2, probably due to the higher intensity in conditioning in group 1. The outcomes with intermediate, low and minimal intensity conditioning were comparable, while all patients after high intensity conditioning died. Table 1 describes Kaplan-Meier estimated 3-year-OS and statistical univariate analysis by log-rank test in the different subgroups. Table 1. 3-year OS (in%) All Group 1 Age 60–65 Group 2 Age 66–76 Remission CR 52 p=0.25 31 p=0.76 77 p=0.15 PR 40 32 50 Conditioning high 0 p=0.5 0 p=0.08 – p=0.38 intermediate 52 50 53 low 48 43 57 minimal 45 17 67 Donor MRD 0 p=0.01 0 p=0.06 73 p=0.45 MUD 57 53 65 MMUD 46 40 33 GVHD acute no 18 p=0.003 13 p=0.008 33 p=0.27 ≥II 43 53 58 chronic no 39 p=0.25 36 p=0.70 52 p=0.08 limited 52 30 100 extensive 50 30 67 In group 1 the outcome of minimal conditioning was inferior compared to intermediate and low conditioning while patients in group 2 had a better outcome with minimal vs. low and intermediate conditioning. Incidences of acute GVHD ≥II, limited and extensive chronic GVHD (cGVHD) were 10%, 28% and 13%, respectively. In group 1, acute GVHD ≥II occurred in 13% and cGVHD in 35%, in group 2 in 5% and 41% of the patients, respectively. Acute GVHD ≥II was associated with inferior outcome (3-year OS of 18% vs. 43%, p=0.003) while cGVHD had a positive impact on OS. In group 2 patients with limited cGVHD showed better 3-year OS than patients without cGVHD (67% vs. 52%, p=0.12). Age alone had no major impact on outcome of allogeneic HCT. Patients aged ≥60 seemed to benefit from the use of MUD rather than an older MRD. Chronic GVHD had a positive influence on survival. Our data indicate that the regimen used should be tailored to disease risk and patient performance status. Disclosures: No relevant conflicts of interest to declare.

Description: Abstract 3319 Poster Board III-207 After hematopoietic stem cell transplantation (HCT) a high incidence of taste and smell alterations is observed which might be associated with delayed physical recovery, general wasting and decreased quality of life. Insufficient nutritional intake can even impair host defense and increase susceptibility to infections. So far, only few systematic evaluations of taste disturbances after HCT have been conducted. We therefore retrospectively analyzed this question using a new standardized questionnaire covering aspects of the dietary pattern and changes in the perception of taste and smell. Clinical data were gathered from patient's charts, and the study was approved by our institutional review board. 181 patients (71 female, 110 male) treated in our institution with a median age of 52 years (range 20-79) were included in the study. The patients completed the questionnaire after a median of 25 months from HCT (range, 1-292). Indications for HCT included acute leukemia =72, myeloproliferative disease =32, lymphoma =29, MDS =10 and other =38. 148 patients received an allogeneic graft after myeloablative conditioning (MAC) (n=87) or reduced-intensitiy-conditioning (RIC) (n=61) and 33 patients were treated with an autologous HCT. 71% of the patients reported moderate to severe changes in taste perception on a semiquantitative visual analogue scale during the acute phase of HCT with no significant differences between the three groups (MAC 74%, RIC 66%, autologous SCT 73%). Changes in smell perception were documented in 54% of patients with a median of 33.5 days (range, 2-365) to improvement. 30% of these patients reported a reduction in smell perception, while 21% described intensification with persistence of these changes in 62% of the patients. In univariate analysis using chi square-tests we examined the difference between autologous and allogeneic transplantation as well as the influence of GvHD or immunosuppression on taste disturbances and loss of weight. Changes in taste perception were significantly associated with loss of body weight 〉 5kg (69.2% vs. 45.6%, p= 0.002). Alterations in body weight and changes in taste perception tended to be more prevalent after allogeneic SCT compared to after autologous HCT with 45.9% vs. 30.3% and 58.1% vs. 45.5%, respectively. A complete recovery at the time of the survey was reported by 29% of the patients, whereas 26% still suffered from ongoing moderate to severe taste alterations. We observed a significant difference in time to recovery with a subjective improvement of symptoms after a median of 60 days (range, 3-365) after autologous HCT vs. 120 days after allogeneic HCT (range, 30-600) (p= 0.03). The incidence of chronic GVHD was 79/148 (53%) in the patients receiving allogeneic HCT. In patients with cGVHD significantly more patients reported changes in taste perception (64.6% vs. 49.0%, p= 0.04) and loss of body weight 〉 5kg (55.7% vs 33.3%, p= 0.004). There was a significant association between the use of immunosuppression and taste alterations using tacrolimus (67.2% vs. 50.0%, p= 0.04) or steroids (72.7% vs. 48.4%, p= 0.03) as well as a loss of weight 〉 5kg using mycophenolatmofetil (53.8% vs. 34.7%, p= 0.01). In conclusion taste and smell disturbances are common events in the early course after HCT. The symptoms persist in one quarter of the patients receiving allogeneic grafts. Interestingly, after allogeneic HCT, no differences between MAC and RIC conditioning but a major impact of GVHD and immunosuppression are observed. Disclosures No relevant conflicts of interest to declare.

Description: Several studies have shown that a single dose of pegylated G-CSF (pegfilgrastim, Neulasta®) administered after chemotherapy allows sufficient collection of hematopoietic progenitor cells (HPC) for autologous transplantation. Pegfilgrastim has not been approved for HPC mobilization, but the decision for stem cell harvesting may be made after pegG-CSF has already been given. In this case, particular kinetics of circulating HPC after pegG-CSF must be taken into account to guide stem cell harvesting. In an intra-individual analysis, we compared mobilization of HPC in 12 lymphoma patients undergoing two identical cycles of salvage chemotherapy (etoposide, ifosfamide, cisplatin, ± epirubicin, ± rituximab) within a clinical trial (ClinicalTrials.gov: NCT00306111). G-CSF (filgrastim, Neupogen® 5 ug/kg/d) was given daily after the 1st cycle starting at day 3, while a single dose of pegfilgrastim (Neulasta®, 6 mg) was administered after the 2nd cycle. Circulating HPC were analyzed by flow cytometry and colony assays. We found that neutrophil recovery was remarkably pronounced after pegG-CSF resulting in a significant higher white blood count at day 12 compared with filgrastim (WBC: 6.8 ± 1.9 G/l vs. 3.2 ± 0.8 G/l, mean ± SEM), but a similar WBC at day 14 and day 16. However, kinetics of circulating HPC were markedly different: A trend to higher numbers of CD34+ progenitors was observed after pegfilgrastim at day 12 compared to filgrastim, followed by a sharp drop at day 14: 25 ± 12 /μl (pegfilgrastim) vs. 69 ± 22 /μl (filgrastim). Particularly the number of more primitive CD34+CD38- progenitors was significantly reduced at day 14: 3.7 ± 3.0 /μl (pegfilgrastim) vs. 11.7 ± 6.3 /μl (filgrastim). Similar results were found for the more primitive CD34+CD133+ und CD34+CD90+ populations. The colony formation (cloning efficiency) of the HPC was not different. Also, coexpression of homing-related receptors (CXCR4, CD62L/L-selectin) was similar in both groups. We conclude that after chemotherapy and pegG-CSF, sufficient numbers of HPC are circulating which allows for HPC collection during the early recovery phase. However, the HPC count is rapidly dropping once the WBC has recovered, in line with the known elimination of pegGCSF by binding to neutrophils. Thus, when a stem cell harvest is scheduled after neutrophil recovery in these patients, daily addition of non-pegylated G-CSF should be considered. Disclosures: Kanz: Amgen GmbH: Research Funding. Möhle:Amgen GmbH: Research Funding. Off Label Use: Pegfilgrastim is not approved for stem cell mobilization.

Description: Haploidentical hematopoietic cell transplantation (HHCT) after high dose conditioning with a megadose of CD34-selected stem cells has been complicated by regimen related toxicities, slow engraftment and delayed immune reconstitution leading to high treatment related mortality (TRM). A new regimen using reduced intensity conditioning (RIC) and immunomagnetic CD3/CD19 graft depletion may allow HHCT with lower toxicity and faster engraftment. CD3/CD19 depleted grafts not only contain CD34+ stem cells but also graft-facilitating cells, CD34- progenitors, dendritic and natural killer cells which may allow stable engraftment even without a megadose of CD34+ cells. A multicenter phase I/II study of HHCT using RIC with fludarabine (150–200 mg/m2), thiotepa (10 mg/kg), melphalan (120 mg/m2), OKT-3 (5 mg/day, day -5 to +14) and CD3/CD19 graft depletion has been initiated. No post grafting immunosuppression was applied if the graft contained 500 granulocytes/μL of 12 days (range, 9–50) and to 〉20000 platelets/μL of 11 days (range, 7–38). Full donor chimerism was reached after 2–4 weeks in all but four patients (median of 14 days (range, 7–215)). Four patients experienced rejection/non-engraftment, two were rescued by a second CD3/CD19 depleted graft from another haploidentical donor. Incidence of grade II-IV acute GVHD was 51% with grade II=16, III=6 and IV=4. So far there are six cases of limited chronic GVHD and one case of extensive chronic GVHD. TRM in the first 100 days was 11/51 (22%) and overall 20/51 (39%). Overall survival is 17/51 patients (33%) with deaths due to relapse (n=14), infection (n=15), PML (n=2), GVHD (n=2) and cardiac failure (n=1), with a median follow-up of alive patients of 397 days (range, 62–1180). This results in a Kaplan-Meier estimate 1-year survival of 37%. So far, we did not observe a statistical significant survival advantage for patient transplanted from a KIR-mismatched donor (28/51 patients). This regimen with low toxicity as well as fast and sustained engraftment is promising in high risk patients lacking a suitable donor. To investigate the treatment protocol earlier in course of disease a new study for high-risk patients with acute leukemia in first complete remission is in preparation.

Description: Abstract 3539 The introduction of reduced intensity conditioning (RIC) regimens in allogeneic hematopoietic cell transplantation (HCT) allows the use of this treatment option even in older, comorbid or heavily pretreated patients. The impact of donor source and match on outcome of HCT after RIC remains to be evaluated. We retrospectively analyzed 254 consecutive adult patients (f=104, m=150) who received allogeneic HCT using RIC treated at our institution between 2000–2010. Median age of patients was 58 years (range, 18–76). Diagnoses were acute leukemia (AML, n=127, ALL, n=9), Non-Hodgkin lymphoma (n=30), multiple myeloma (n=29), myelodysplastic syndrome (n=27), osteomyelofibrosis (n=19), chronic myeloid leukemia (n=5), chronic lymphatic leukemia (n=5) and Hodgkin lymphoma (n=3). 91 patients were transplanted in complete remission (CR), 163 in partial remission (PR). 49 patients were transplanted from a matched related donor (MRD), 93 from a matched unrelated donor (MUD), 68 from a mismatched unrelated donor (MMUD, up to 2 allel/antigen mismatches), 3 from a mismatched related donor and 41 from a haploidentical donor (haplo). Remission status at time of HCT in patients transplanted from haplo donors (21 CR, 20 PR) was balanced, whereas patients transplanted from MRD (10 CR, 39 PR), MUD (36 CR, 57 PR) or MMUD (24 CR, 47 PR) were predominantly in PR. 82 of the patients were high-risk because of preceding autologous or allogeneic HCT (MRD=19, MUD=27, MMUD=11, haplo=25). Kaplan-Meier estimated 3-year overall survival (OS) for all patients was 45%, 47% with MRD, 46% with MUD, 53% with MMUD and 29% with haplo (p=0.07). Kaplan Meier estimated 3-year-OS and statistical analysis by univariate log-rank test in different subgroups are described in table 1. Table 1 3-year OS (in %) MRD p MUD p MMUD p Haplo p Remission CR 39 49 62 29 0.30 PR 49 45 49 28 0.19 NRM 22 34 28 39 0.24 aGVHD 3II 100 0.49 13 0.001 53 0.91 25 0.91 no aGVHD 3II 40 51 50 23 cGVHD no 48 0.97 40 0.07 56 0.93 16 0.03 limited 75 39 50 50 extensive 35 66 57 53 Donor source and match had no significant impact on OS in the different subgroups. Non-relapse mortality was 31% without a difference between different donors. 3-year OS in the biggest diagnostic group AML was 47% with MUD, 51% with MMUD, 30% with MRD and 31% with haplo, respectively (p=0.38). Incidence of acute GVHD (aGVHD) ≥II was 14% (4% with MRD, 15% with MUD, 15% with MMUD and 17% with haplo) with a lower incidence of acute GVHD with MRD compared to haplo (p=0.02). Incidence of chronic GVHD (cGVHD) was 37% (33% with MRD, 45% with MUD, 33% with MMUD and 34% with haplo). Presence of aGVHD ≥II was associated with an inferior outcome (3-year OS 30 vs. 45%, p=0.02) while presence of limited or extensive cGVHD was associated with an improved OS (52% and 50% vs. 39% without cGVHD, p= 0.25). cGVHD had a positive impact on OS especially after HCT with MUD (p=0.07) or haplo (p=0.03) Thus, RIC for allogeneic HCT in elderly or heavily pretreated patients shows promising results irrespective of donor source. The lack of a MRD should not preclude MUD or MMUD allogeneic HCT using RIC in elderly patients. Disclosures: No relevant conflicts of interest to declare.

Description: Abstract 1938 Introduction: Patients with relapsed or primary refractory AML have a dismal prognosis. Even salvage therapy with allogeneic hematopoietic cell transplantation (HCT) could not improve outcome due to high incidence of relapse and high non-relapse mortality (NRM). Recently, promising results in patients with unfavorable karyotype or treatment refractory AML have been reported using a sequential treatment with aplasia inducing chemotherapy consisting of Fludarabine, Ara-C and Amsacrine (FLAMSA) followed within 3 days by reduced intensity conditioning (RIC) for allogeneic HCT (Schmid et al., Blood 2006 Aug 1;108(3):1092–9). Methods: We report a retrospective analysis of our single center experience with FLAMSA-RIC in primary refractory or relapsed AML patients. We searched our database for patients receiving FLAMSA-RIC in the past 10 years. Details on characteristics and clinical course of the patients were confirmed by retrospective chart review. Results: We retrospectively identified and analyzed 51 consecutive patients (f=22, m=29) transplanted after FLAMSA-RIC at our institution from 2006–2011. At time of HCT patients were refractory after chemotherapy (n=22) or had an untreated relapse (n=29). Data on molecular and cytogenetic markers were available in 36 and 44 patients, respectively. 34 were initially high-risk because of unfavorable karyotype (n=25) or molecular genetic alterations (n=9). Median age of patients was 56 years (range, 20–72) and diagnosis of all patients was acute myeloid leukemia (de-novo AML, n=27, secondary AML, n=24). FLAMSA (Fludarabine 30 mg/m2 day −12 to −9, AraC 2000 mg/m2 day −12 to −11 and Amsacrine 100 mg/m2 day −12 to −9) was used as salvage therapy followed by RIC (Fludarabine 30 mg/m2 day −5 to −4/Busulfan 0.8 mg/kg day −6 to −4, n=10; TBI 4Gy on day −5/Cyclophosphamide 60 mg/kg on day −4 to −3, n=28; Busulfan 0.8 mg/kg day −6 to −4/Cyclophosphamide 60 mg/kg for matched and mismatched unrelated donors (MUD/MMUD) or 40 mg/kg for matched related donors (MRD) on day −3 to −2, n=13). As GVHD prophylaxis calcineurin inhibitor combined with mycophenolate mofetil and anti-thymocyte globuline (ATG-Fresenius®, 10 mg/kg for MRD and 20 mg/kg for MUD/MMUD) was used. 10 patients were transplanted from MRD, 16 from MUD, 21 from a MMUD and 4 from a MMRD. 14 patients received DLI (2 × 106 - 1 × 108 /kg after a median of 186 days, range 72–922) in absence of GVHD in case of mixed chimerism or relapse after HCT. Current overall survival (OS) was 18/51 patients with a median follow-up of 410 days (range, 179–1557) of patients alive resulting in a Kaplan-Meier estimated 2-year OS and event-free-survival (EFS) of 34% and 29%, respectively. There was no significant difference between the different RIC regimens with 50% Fludarabine / Busulfan vs. 26% TBI 4Gy / Cyclophosphamide and 40% Fludarabine / Busulfan (p=0.37). Causes of death were relapse (n=19), infections (n=5), GVHD (n=2), multi-organ-failure (n=5), cerebral hemorrhage (n=1) and progressive multifocal leukencephalopathy (n=1). Cumulative incidence of relapse at 2 years with death due to NRM as competing risk was 40% and cumulative incidence at 2 years of NRM with death due to relapse as competing risk was 27%. 2-year OS was inferior in patients with secondary AML compared to patients with de-novo AML (28% vs. 38% p=0.79). The outcome in the elderly subgroup defined by age ≥60 years (median age 67, n=22) was similar to the group of younger patients (median age 46, n=29) with 2-year OS of 31% vs. 37% (p=0.87). Patients with a blast count 〈 10% in the bone marrow at time of HCT had a better outcome with 64% vs. 25% OS (p=0.09). 2-year-OS was inferior in patients being refractory after chemotherapy (25% vs 38%, p=0.78). Incidence of acute GVHD (aGVHD) ≥II and chronic GVHD (cGVHD, limited, n=11, extensive, n=3) was 22% and 27%, respectively. Presence of aGVHD did not influence survival while presence of cGVHD was associated with an improved overall survival after HCT (58% vs 24%, p=0.009). Conclusion: FLAMSA-RIC followed by allogeneic HCT enables long-term disease free survival, even in primary refractory or relapsed AML patients. The sequential approach of this regimen seems to overcome the dismal prognosis of these patients. Its moderate toxicity allows the application of this curative salvage therapy option even in an elderly patient population. Disclosures: Off Label Use: The use of some agents in the conditioning is off-label.

Description: Abstract 1203 Poster Board I-225 HHCT using reduced intensity conditioning (RIC) and immunomagnetic CD3/CD19 graft depletion is of low toxicity and enables fast engraftment even with grafts of low CD34 content. Immune reconstitution may be improved compared to graft CD34 selection due to the cotransplantation of facilitating cells, CD34- progenitors, dendritic cells and natural killer (NK)-cells. A prospective multicenter phase II study of HHCT using CD3/CD19-depleted grafts after RIC with fludarabine (150-200 mg/m2), thiotepa (10 mg/kg), melphalan (120 mg/m2), OKT-3 (5 mg/day, day -5 to +14) was initiated. No post grafting immunosuppression was applied if the graft contained 500 granulocytes/μL (range, 9-50) and 11 days to 〉20.000 platelets/μL (range, 7-38). Incidence of grade II-IV acute GVHD and chronic GvHD (cGvHD) was 47% and 15%, respectively. Non-relapse-mortality on day 100 was 25% and 44% for the whole study period. Current overall survival (OS) is 18 of 60 patients (30%) with median follow-up of 525 days (range, 21-1542) of patients alive resulting in a Kaplan-Meier estimate 1-year OS of 41% and 2-year OS of 24%. Kaplan-Meier estimate 1-year OS was 40 % in AML, 38 % in ALL and 67% in NHL patients. No positive impact of KIR-mismatch on survival even in the subgroup of patients with AML was observed. Patients with cGVHD had a trend toward better survival with 56% vs. 39% (p=0.09). 14 patients died because of infections. Detailed immune reconstitution was analyzed in 24 patients. NK-cell engraftment was fast with median of 248 CD16+56+CD3- cells/μl (range, 1-886) on day 20. Increased natural cytotoxicity receptors (NKP30, NKP44, NKP46) and NKG2A, but decreased NKG2D and KIR-expression was observed on NK-cells in the first 3 months. T-cells regenerated delayed with median of 191 CD3+ cells/μl (range, 38-799) on day 100. A slow reconstitution of CD8+ and CD4+ T-cells with median of 66 CD8+ (range, 8-170) vs. 70 CD4+ cells/μl (range, 12-301) on day 100 and 157 (range, 32-379) vs. 181 cells/μl (range, 19-980) on day 400 was observed. The subset of memory T-cells regenerated faster compared to naïve T-cells with median of 25 CD4+45RA+ (range, 4-109) vs. 80 CD4+45RO+ cells/μl (range, 0 to 255) and 46 (range 7-191) vs. 164 cells/μl (range, 66-323) on days 80 and 250, respectively. T-cell repertoire was skewed with oligoclonal T-cell expansion to day 100 and normalization after day 200. B-cell reconstitution was slow with median of 8 (range, 0-407) CD19+20+ cells/μl on day 100. 6 of these 24 patients received donor-lymphocyte-infusions for relapse or mixed chimerism resulting in acceleration of immune recovery in T- and NK-cells. In conclusion, HHCT using RIC and CD3/CD19 depleted grafts is of low toxicity and allows fast engraftment even with low doses of CD34 cells. Overall survival seems promising in a high risk patient cohort. Recovery of NK cells occurs early and fast. KIR receptor expression remains low in the first 3 months. T- and B-cell reconstitution is delayed but seems faster compared to published data after CD34 selection. To evaluate the treatment protocol earlier during the course of disease a new study has just been initiated. Disclosures: Off Label Use: The use of Fludarabine, Thiotepa, Melphalan and OKT-3 in the conditioning is off-label-use.

Description: Abstract 4482 Introduction: Allogeneic hematopoietic cell transplantation (HCT) following reduced-intensity conditioning (RIC) including radioimmunotherapy (RIT) with yttrium-90 ibritumomab tiuxetan is a potential salvage treatment for patients with advanced high-risk B-cell lymphoma. The influence of RIT combined with RIC on immune reconstitution after allogeneic HCT has not been evaluated. Methods: We compared data on immune reconstitution of 14 patients receiving allogeneic HCT after RIT-RIC at our institution from 2006 to 2008. Yttrium-90 ibritumomab tiuxetan as RIT and RIC with either fludarabine (30 mg/m2, day −8 to −4)/melphalan (140 mg/m2, day −3)/alemtuzumab (20 mg for related donors and 30 mg for unrelated donors, day −3 and −2) (n=7, FLU/MEL/AL-RIT group) or fludarabine (30 mg/m2, day −4 to −2)/2 Gy total body irradiation (day 0) (n=7, FLU/TBI-RIT group) were used. Immunosuppression consisted of cyclosporine A alone (FLU/MEL/AL-RIT group) or cyclosporine A combined with mycophenolate mofetil (FLU/TBI-RIT group). The results were compared to 14 patients in a concurrent control group with similar conditioning regimens without RIT (n=7, FLU/MEL (without alemtuzumab); n=7, FLU/TBI). Differences in engraftment and immune reconstitution were evaluated. Results: Diagnoses in the RIT groups were high-grade NHL (n=6), low-grade NHL (n=6) and CLL (n=2). In the control groups diagnoses were high-grade NHL (n=4), acute leukemia (n=6), MDS (n=1), multiple myeloma (n=1), Hodgkin's lymphoma (n=1) and CLL (n=1). Neutrophil engraftment (〉500/μl) was observed after a median of 20 days (range 13–26) in the FLU/MEL/AL-RIT-group compared to 15 days (range 11–21) in the control group (p=0.11). After a median of 13 days (range 7–17) and 12 days (range 8–27) neutrophil engraftment was noted in the FLU/TBI-RIT group and control group, respectively (p=0.40). Median time to thrombocyte engraftment (〉20,000/μl) was 11 days (range 8–42) in the FLU/MEL/AL-RIT-group and 21 days (range 5–29) in the control group (p=0.81). After a median of 10 days (range 7–16) and 11 days (range 10–35) thrombocyte engraftment was noted in the FLU/TBI-RIT group and control group, respectively (p=0.23). Immune reconstitution in the four groups is shown in Table 1: Regeneration of CD3+8+ T-cells on day +100 and day +500 was significantly (p

Description: Abstract 3101 Natural killer (NK) cell alloreactivity, after allogeneic hematopoietic cell transplantation (HCT) is influenced by the interaction of killer-cell immunoglobulin-like receptors (KIRs) on donor NK cells and human leukocyte antigen (HLA) class I ligands on recipient cells. Recently, a positive influence of KIR haplotype B versus haplotype A donors on the outcome of HLA-matched allogeneic HCT was demonstrated (Cooley et al., Blood 2010). Previously, Ruggeri et al. (Science 2002) reported the positive influence of KIR-ligand mismatch (MM) on outcome of haploidentical HCT (HHCT). Here we investigated the influence of the donor KIR haplotype and KIR-ligand MM on relapse of 57 patients with hematologic malignancies receiving HHCT after reduced intensity conditioning and graft CD3/CD19 depletion. 36 patients with AML, eight with ALL, four with multiple myeloma, four with NHL and one with MCL, CML, CMML, MDS, CLL, respectively (median age 45 years, range 19–61 years) were evaluated. Patients were “high risk” because of relapse (n=8), prior HCT (n=23), refractory disease (n=20) or cytogenetic risk (n=6). At HHCT, 29 patients were in complete remission (CR) and 28 in partial remission (PR). 15 KIR genes were determined by real-time PCR as described (Vilches et al., Tissue Antigens 2007, Alves et al., Tissue Antigens 2009), and donors were assigned the A/A or B/x haplotype. Patients and donors were HLA-typed by high-resolution molecular methods. Of the 57 donors, 17 had KIR haplotype A (29.8%) and 40 KIR haplotype B (70.2%). A KIR-ligand MM was found in 34 of 57 patients (59.6%). Cumulative incidence adjusted for competing risk showed no difference between KIR haplotype A or B patients regarding non-relapse mortality (NRM) (Gray's test: p=0.200), but a significantly reduced incidence of relapse for patients with a haplotype B donor (p=0.001). In particular, patients in PR benefited more from a haplotype B graft (p=0.008) than patients in CR (p=0.297). This resulted in a trend in the Kaplan-Meier estimated event free (EFS) at 3 years of 26.8 % for KIR haplotype B and 11.7 % for KIR haplotype A (HR=1.33 [CI=0.66–2.70], log rank test: p=0.422). In detail, all patients in PR died within 1.2 years when haplotype A donor cells were transplanted whereas 25% of haplotype B recipients were still alive after 3 years (HR=1.27 [CI=0.49–3.30], p=0.631). In comparison, 16.6% of haplotype A and 28.1% of haplotype B recipients in CR survived for more than 3 years (HR=1.46 [CI=0.54–3.94], p=0681). Surprisingly, KIR-ligand MM cumulative incidence curves were not statistically different for relapse (p=0680) or NRM (p=0.579). In addition, KIR-ligand MM resulted in a trend for decreased EFS rate for MM patients (17.6%) in contrast to matched patients (33.7%; HR=1.47 [CI=0.89–2.75], p=0.230). These effects were even more pronounced when analyzing the patient cohort with AML. Of the 36 donors, 10 showed KIR haplotype A (27.8%), 26 KIR haplotype B (72.2%) and KIR-ligand MM was present in 25 patients (69.4%). EFS at 3 years was prolonged for KIR haplotype B graft recipients (EFS: HR=2.29 [CI=0.88–5.96], p=0.087). In addition, cumulative incidence adjusted for competing risk analysis revealed a reduced incidence of relapse for patients with a haplotype B donor (all AML patients: p=0.079, AML in PR: p=0.049), but not for NRM (all AML patients: p=0.806, AML in PR: p=0.674). Again, KIR-ligand MM cumulative incidence curves were not significantly different for both relapse (p=0.126) and NRM (p=0.535). In line, KIR-ligand MM led to decreased EFS rate for MM patients (16.0%) in contrast to matched patients (53.0%; HR=2.27 [CI=1.08–5.06], p=0.045). Taken together, in the setting of RIC and CD3/CD19 depleted HHCT we could not confirm the positive data with KIR-ligand MM but observed a significant lower risk of relapse with a KIR haplotype B donor. We therefore conclude from our results that a donor KIR B haplotype should be favored as donor for HHCT using RIC and CD3/CD19 depletion in patients with hematological malignancies, particularly if no complete remission has been achieved prior to HHCT. Disclosures: Off Label Use: off lable use of drugs for conditioning.