Risk assessment with low-pass whole-genome sequencing of cell-free DNA before CD19 CAR T-cell therapy for large B-cell lymphoma.

Patients with relapsed or refractory large B-cell lymphomas (rrLBCL) can achieve long-term remission after CD19 chimeric antigen receptor T-cell therapy (CART19). However, more than half of recipients will experience treatment failure. Thus, approaches are needed to identify high-risk patients who may benefit from alternative or consolidative therapy. We evaluated low-pass whole-genome sequencing (lpWGS) of cell-free DNA (cfDNA) before CART19 as a new approach for risk stratification. We performed lpWGS on pretreatment plasma samples from 122 patients at time of leukapheresis who received standard-of-care CART19 for rrLBCL to define DNA copy number alterations (CNAs). In multivariable selection, high focal CNA score (FCS) denoting genomic instability was the most significant pretreatment variable associated with inferior 3-month complete response rates (28% vs 56%, P = .0029), progression-free survival (PFS; P = .0007; hazard ratio, 2.11), and overall survival (OS; P = .0026; hazard ratio, 2.10). We identified 34 unique focal CNAs in 108 (89%) patients; of these, deletion 10q23.3 leading to loss of FAS death receptor was the most highly associated with poor outcomes, leading to inferior PFS (P < .0001; hazard ratio, 3.49) and OS (P = .0027; hazard ratio, 2.68). By combining FCS with traditional markers of increased tumor bulk (elevated lactate dehydrogenase and >1 extranodal site), we built a simple risk model that could reliably risk stratify patients. Thus, lpWGS of cfDNA is a minimally invasive assay that could rapidly identify high-risk patients and may guide patient selection for and targeted therapies to evaluate in future clinical trials.

Prognostic impact of corticosteroids on efficacy of chimeric antigen receptor T-cell therapy in large B-cell lymphoma.

Corticosteroids are commonly used for the management of severe toxicities associated with chimeric antigen receptor (CAR) T-cell therapy. However, it remains unclear whether their dose, duration, and timing may affect clinical efficacy. Here, we determined the impact of corticosteroids on clinical outcomes in patients with relapsed or refractory large B-cell lymphoma treated with standard of care anti-CD19 CAR T-cell therapy. Among 100 patients evaluated, 60 (60%) received corticosteroids for management of CAR T-cell therapy-associated toxicities. The median cumulative dexamethasone-equivalent dose was 186 mg (range, 8-1803) and the median duration of corticosteroid treatment was 9 days (range, 1-30). Corticosteroid treatment was started between days 0 and 7 in 45 (75%) patients and beyond day 7 in 15 (25%). After a median follow-up of 10 months (95% confidence interval, 8-12 months), use of higher cumulative dose of corticosteroids was associated with significantly shorter progression-free survival. More importantly, higher cumulative dose of corticosteroids, and prolonged and early use after CAR T-cell infusion were associated with significantly shorter overall survival. These results suggest that corticosteroids should be used at the lowest dose and for the shortest duration and their initiation should be delayed whenever clinically feasible while managing CAR T-cell therapy-associated toxicities.

Allogeneic cord blood regulatory T cells can resolve lung inflammation.

BACKGROUND AIMS: CD4+CD25+CD127lo regulatory T cells (Tregs) are responsible for maintaining immune homeostasis. Tregs can be rendered defective and deficient as a result of the immune imbalance seen in lung injury, and such dysfunction can play a major role in continued tissue inflammation. The authors hypothesized that adoptive therapy with healthy allogeneic umbilical cord blood (UCB)-derived Tregs may be able to resolve inflammation. RESULTS: Ex vivo-expanded UCB Tregs exhibited a unique phenotype with co-expression of CD45RA+CD45RO+ >80% and lung homing markers, including CD49d. UCB Tregs did not turn pathogenic when exposed to IL-6. Co-culture with increasing doses of dexamethasone led to a synergistic increase in UCB Treg-induced apoptosis of conventional T cells (Tcons), which translated into significantly higher suppression of proliferating Tcons, especially at a lower Treg:Tcon ratio. Multiple injections of UCB Tregs led to their preferential accumulation in lung tissue in an immune injury xenogenic model. A significant decrease in lung resident cytotoxic CD8+ T cells (P = 0.0218) correlated with a sustained decrease in their systemic distribution compared with controls (P < 0.0001) (n = 7 per arm) as well as a decrease in circulating human soluble CD40 ligand level (P = 0.031). Tissue architecture was preserved in the treatment arm, and a significant decrease in CD3+ and CD8+ burden was evident in immunohistochemistry analysis. CONCLUSIONS: UCB Treg adoptive therapy is a promising therapeutic strategy for treatment of lung injury.

Improved outcomes of high-risk relapsed Hodgkin lymphoma patients after high-dose chemotherapy: a 15-year analysis.

High-dose chemotherapy and autologous stem-cell transplant (HDC/ASCT) is standard treatment for chemosensitive relapsed classical Hodgkin lymphoma, although outcomes of high-risk relapse (HRR) patients remain suboptimal. We retrospectively analyzed all HRR classical Hodgkin lymphoma patients treated with HDC/ASCT at our institution between 01/01/2005 and 12/31/2019. HRR criteria included primary refractory disease/relapse within 1 year, extranodal extension, B symptoms, requiring more than one salvage line, or positron emission tomography (PET)-positive disease at ASCT. All patients met the same ASCT eligibility criteria. We treated 501 patients with BEAM (n=146), busulphan/melphalan (BuMel) (n=38), gemcitabine( Gem)/BuMel (n=189) and vorinostat/Gem/BuMel (n=128). The Gem/BuMel and vorinostat/Gem/BuMel cohorts had more HRR criteria and more patients with PET-positive disease at ASCT. Treatment with brentuximab vedotin (BV) or anti-PD1 prior to ASCT, PET-negative disease at ASCT, and maintenance BV increased over time. BEAM and BuMel predominated in earlier years (2005-2007), GemBuMel and BEAM in middle years (2008-2015), and vorinostat/GemBuMel and BEAM in later years (2016-2019). The median follow-up is 50 months (range, 6-186). Outcomes improved over time, with 2-year progressionfree survival (PFS)/overall survival (OS) rates of 58%/82% (2005-2007), 59%/83% (2008-2011), 71%/94% (2012-2015) and 86%/99% (2016- 2019) (P<0.0001). Five-year PFS/OS rates were 72%/87% after vorinostat/ GemBuMel, 55%/75% after GemBuMel, 45%/61% after BEAM, and 39%/57% after BuMel (PFS: P=0.0003; OS: P<0.0001). These differences persisted within the PET-negative and PET-positive subgroups. Prior BV and vorinostat/GemBuMel were independent predictors of more favorable outcome, whereas primary refractory disease, ≥2 salvage lines, bulky relapse, B symptoms and PET-positivity at ASCT correlated independently with unfavorable outcomes. In conclusion, post-HDC/ASCT outcomes of patients with HRR classic Hodgkin lymphoma have improved over the last 15 years. Pre-ASCT BV treatment and optimized synergistic HDC (vorinostat/GemBuMel) were associated with this improvement.

Cytogenetics and Blast Count Determine Transplant Outcomes in Patients with Active Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) patients not in remission and beyond first or second complete remission are considered allogeneic stem cell transplant (SCT) candidates. We present 361 patients who underwent SCT from matched related or unrelated donors between 2005 and 2013. The purpose was to identify a subgroup of patients with active disease at the time of transplant that benefit. Cox proportional hazards regression analysis was used for univariate and multivariate analyses to predict overall survival (OS). Variables considered were age, sex, SWOG cytogenetic risk group, bone marrow (BM) and peripheral blood (PB) blast percentage, regimen intensity, and type of AML. At a median of 26 months after transplantation, OS, progression-free survival (PFS), non-relapse mortality, and relapse rates were 26, 24, 23, and 48%, respectively. In a univariate analysis, risk cytogenetics (p < 0.001) and BM blasts >4% (p = 0.006) or any blasts in PB (p < 0.001) indicated worse OS. In a multivariate analysis, patients with <5% BM blasts or absence of circulating blasts and good or intermediate risk cytogenetics had significantly superior OS (46%), PFS (44%), and disease progression at 3 years. Based on these findings, patients not in remission with good or intermediate risk cytogenetics and low blast counts should be considered for SCT.

Comparison of Outcomes of Allogeneic Hematopoietic Cell Transplantation for Multiple Myeloma Using Three Different Conditioning Regimens.

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative therapy for patients with multiple myeloma, as it provides a graft-versus-myeloma effect alongside a myeloma-free graft. Although reduced-intensity conditioning regimens decrease nonrelapse mortality (NRM), there is a paucity of data with regard to the ideal conditioning regimen in myeloma. We conducted a retrospective comparison of 3 different preparative regimens used for allo-HCT for multiple myeloma at our institution in recent clinical trials: busulfan/fludarabine (BuFlu), fludarabine/melphalan 100 mg/m2 (FM100), and fludarabine/melphalan 140 mg/m2 (FM140). NRM, progression-free survival (PFS) at 3 years, and overall survival (OS) at 3 years were the primary endpoints. Secondary endpoints included time to engraftment, and the incidence of grades II through IV acute graft-versus-host disease and chronic graft-versus-host disease. A total of 73 patients received allo-HCT with these regimens. NRM at 3 years was seen in 3 (21%), 5 (28%), and 6 (24%) patients in the BuFlu, FM100, and FM140 groups, respectively. Three-year PFS in the BuFlu, FM100, and FM140 groups was 16% (hazard ratio [HR], 1.2; 95% confidence interval [CI], 0.6 to 2.1), 26% (HR, 0.6; 95% CI, 0.3 to 1.2), and 11% (reference), respectively. Three-year OS in the BuFlu, FM100, and FM140 groups was 39% (HR, 1.1; 95% CI, 0.5 to 2.2), 43% (HR, 0.7; 95% CI, 0.3 to 1.4), and 32% (reference), respectively. High-risk cytogenetics and relapsed disease prior to allo-HCT were found to be independent predictors of inferior OS on multivariate analysis, with a HR of 2.1 (P = .02) and 2.6 (P = .004), respectively. In contrast, the preparative regimen did not emerge as a predictor of PFS or OS. Durable clinical remission can be achieved in 11% to 25% of patients with multiple myeloma with the use of allo-HCT without any significant difference in the safety or efficacy of the conditioning regimen. High-risk cytogenetics and relapsed disease prior to transplant were associated with inferior PFS and OS.

Impact of Donor Type and Melphalan Dose on Allogeneic Transplantation Outcomes for Patients with Lymphoma.

We analyzed 186 patients with lymphoma who underwent allogeneic stem cell transplantation (ASCT) with fludarabine-melphalan (FM) conditioning and different types of donors (25 haploidentical [HD], 98 matched unrelated [MUD], and 63 matched related [MRD]) at our institution between September 2009 and January 2018. Patients received fludarabine 160 mg/m2 (40 mg/m2/day for 4 days) in combination with 1 dose of melphalan 140 mg/m2 (FM140) or 100 mg/m2 (FM100). Engraftment was similar among the 3 groups (92%, 89%, and 98%, respectively; P = .7). The 6-month cumulative incidence of grade III-IV acute graft-versus-host disease (GVHD) was 4% in the HD group, 14% in the MUD group, and 8% in the MRD group (P not significant), and the respective 3-year cumulative incidence of chronic GVHD was 5%, 16%, and 26% (P not significant). The respective 3-year nonrelapse mortality and relapse rates were 31%, 32%, and 10% (HD versus MUD, P = .9; HD versus MRD, P = .02) and 15%, 21%, and 39% (HD versus MUD, P = .4; HD versus MRD, P = .04). At 3 years, progression-free survival (PFS) was 59%, 44%, and 46% (P not significant); overall survival (OS) was 52%, 54%, and 67% (P not significant); and GVHD-free, relapse-free survival was 39%, 31%, and 24% (P not significant). No differences in the 3-year PFS (57% versus 43%; P = .3) and OS (64% versus 58%; P = .7) were seen between patients receiving FM100 and those receiving FM140. Our data demonstrate that in patients with lymphoma, ASCT with HD transplants have similar outcomes as ASCT with HLA-matched transplants, and the FM100 conditioning regimen appears to be at least as effective as the FM140 regimen.

Impact of Induction Therapy on the Outcome of Immunoglobulin Light Chain Amyloidosis after Autologous Hematopoietic Stem Cell Transplantation.

With the availability of immunomodulatory imide drugs (IMiDs) and proteasome inhibitors (PI), most patients with immunoglobulin light chain amyloidosis (AL) receive induction therapy before autologous hematopoietic stem cell transplantation (auto-HCT). In this study we evaluated the type of induction therapy and its impact on the outcome of auto-HCT in AL. We identified 128 patients with AL who underwent high-dose chemotherapy and auto-HCT at our institution between 1997 and 2013. Patients were divided into 3 groups: no induction, conventional chemotherapy (CC)-based induction (melphalan, steroids), and IMiD/PI-based induction (thalidomide, lenalidomide, or bortezomib). The hematologic response (HR) and organ response were defined according to the established criteria. Median age at auto-HCT was 58 years (range, 35 to 75). Twenty patients (15.5%) received no induction, 25 (19.5%) received CC, and 83 (65%) received IMiDs/PIs. One, 2, or 3 or more organs were involved in 90 (70%), 20 (16%), and 18 (14%) patients, respectively. After auto-HCT 12 of 20 (60%), 15 of 24 (62%), and 72 of 83 (87%) assessable patients achieved HR at 100 days in no induction, CC, and IMiD/PI groups, respectively (P = .001). Organ response at 1 year after auto-HCT was seen in 7 of 18 (39%), 14 of 24 (58%), and 37 of 79 (47%) assessable patients in no induction, CC, and IMiD/PI groups, respectively (P = .3). Achieving a hematologic complete response was associated with a significantly higher probability of achieving an organ response (P = .02). After a median follow-up of 26 months, rates of 2-year progression-free survival were 67%, 56%, and 73% in no induction, CC, and IMiD/PI groups, respectively (P = .07; hazard ratio, .5; 95% confidence interval [CI], .3 to 1.1). Rates of 2-year overall survival were 73%, 76%, and 87% in no induction, CC, and IMiD/PI groups, respectively (P = .05; hazard ratio, .4; 95% CI, .2 to .9). On multivariate analysis a low ß2-microglobulin (P = .01; hazard ratio, .3; 95% CI, .1 to .7) and induction therapy with IMiD/PI (P = .01; hazard ratio, .3; 95% CI, .1 to .7) were associated with a better overall survival. Induction therapy with either CC or IMiDs/PIs is safe and feasible in selected patients with AL. IMiD/PI-based induction is associated with a longer overall survival compared with patients who received no induction or CC before auto-HCT.

Haploidentical Transplantation for Older Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome.

Allogeneic stem cell transplantation with HLA-matched donors is increasingly used for older patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). It remains unclear if haploidentical stem cell transplantation (haploSCT) is a suitable option for older patients with this disease. We analyzed 43 patients with AML/MDS (median age, 61 years) who underwent a haploSCT at our institution. All patients received a fludarabine-melphalan-based reduced-intensity conditioning regimen and post-transplant cyclophosphamide-based graft-versus-host disease (GVHD) prophylaxis. Except for 1 patient who had early death, the remaining 42 patients (98%) engrafted donor cells. The cumulative incidences of grades II to IV and III to IV acute GVHD at 6 months were 35% and 5%, respectively, and chronic GVHD at 2 years was 9%. After a median follow-up of 19 months, 2-year overall survival, progression-free survival (PFS), and relapse incidence were 42%, 42%, and 24%, respectively. Best PFS (74% at 2 years) was seen in patients with intermediate-/good-risk cytogenetics, in first or second remission (hazard ratio, .4; P = .05), and with a younger donor (≤40 years; hazard ratio, .2; P = .01). In conclusion, these data suggest that haploidentical transplantation is safe and effective for older AML/MDS patients. Disease status, cytogenetics, and younger donor age are predictors for improved survival in older patients receiving a haploidentical transplant.

Specific combinations of donor and recipient KIR-HLA genotypes predict for large differences in outcome after cord blood transplantation.

The ability of cord blood transplantation (CBT) to prevent relapse depends partly on donor natural killer (NK) cell alloreactivity. NK effector function depends on specific killer-cell immunoglobulin-like receptors (KIR) and HLA interactions. Thus, it is important to identify optimal combinations of KIR-HLA genotypes in donors and recipients that could improve CBT outcome. We studied clinical data, KIR and HLA genotypes, and NK-cell reconstitution in CBT patients (n = 110). Results were validated in an independent cohort (n = 94). HLA-KIR genotyping of recipient germline and transplanted cord blood (CB) grafts predicted for large differences in outcome. Patients homozygous for HLA-C2 group alleles had higher 1-year relapse rate and worse survival after CBT than did HLA-C1/C1 or HLA-C1/C2 (HLA-C1/x) patients: 67.8% vs 26.0% and 15.0% vs 52.9%, respectively. This inferior outcome was associated with delayed posttransplant recovery of NK cells expressing the HLA-C2-specific KIR2DL1/S1 receptors. HLA-C1/x patients receiving a CB graft with the combined HLA-C1-KIR2DL2/L3/S2 genotype had lower 1-year relapse rate (6.7% vs 40.1%) and superior survival (74.2% vs 41.3%) compared with recipients of grafts lacking KIR2DS2 or HLA-C1 HLA-C2/C2 patients had lower relapse rate (44.7% vs 93.4%) and better survival (30.1% vs 0%) if they received a graft with the combined HLA-C2-KIR2DL1/S1 genotype. Relapsed/refractory disease at CBT, recipient HLA-C2/C2 genotype, and donor HLA-KIR genotype were independent predictors of outcome. Thus, we propose the inclusion of KIR genotyping in graft selection criteria for CBT. HLA-C1/x patients should receive an HLA-C1-KIR2DL2/L3/S2 CB graft, while HLA-C2/C2 patients may benefit from an HLA-C2-KIR2DL1/S1 graft.

Ex Vivo Mesenchymal Precursor Cell-Expanded Cord Blood Transplantation after Reduced-Intensity Conditioning Regimens Improves Time to Neutrophil Recovery.

We previously showed the safety of using cord blood (CB) expanded ex vivo in cocultures with allogeneic mesenchymal precursor cells (MPC) after myeloablative conditioning with faster recovery of neutrophils and platelets compared with historical controls. Herein, we report the transplantation outcomes of 27 patients with hematologic cancers who received 1 CB unit expanded ex vivo with MPCs in addition to an unmanipulated CB (MPC group) after reduced-intensity conditioning (RIC). The results in this group were compared with 51 historical controls who received 2 unmanipulated CB units (control group). The analyses were stratified for 2 RIC treatment groups: (1) total body irradiation 200 cGy + cyclophosphamide + fludarabine) (TCF), and (2) fludarabine + melphalan (FM). Coculture of CB with MPCs led to an expansion of total nucleated cells by a median factor of 12 and of CD34+ cells by a median factor of 49. In patients in whom engraftment occurred, the median time to neutrophil engraftment was 12 days in the MPC group, as compared with 16 days in controls (P = .02). The faster neutrophil engraftment was observed in both RIC groups. The cumulative incidence of neutrophil engraftment on day 26 was 75% with expansion versus 50% without expansion in patients who received FM as the RIC regimen (P = .03). Incidence of neutrophil engraftment was comparable in MPC and control groups if treated with TCF (82% versus 79%, P = .40). Transplantation of CB units expanded with MPCs is safe and effective with faster neutrophil engraftment even after RIC regimens.

Outcome of autologous hematopoietic stem cell transplantation in refractory multiple myeloma.

BACKGROUND: Despite the introduction of effective, novel agents, the outcome of patients with refractory multiple myeloma remains poor, particularly those who are refractory to both proteasome inhibitors (PIs) and immunomodulatory agents (IMiDs). Limited data are available on the role of autologous hematopoietic stem cell transplantation in this population. METHODS: Patients with refractory myeloma who underwent first autologous hematopoietic stem cell transplantation (auto-HCT) between March 2000 and October 2015 were retrospectively analyzed. Those who had primary refractory disease and those with relapsed and refractory disease were included. Disease that was refractory to at least 1 PI and at least 1 IMiD was classified as double-refractory multiple myeloma (DR-MM). RESULTS: In total, 233 patients were identified, including 105 (45%) classified with DR-MM and 128 (55%) classified with nondouble-refractory myeloma (NDR-MM). At a median follow-up of 42 months for surviving patients, at least a partial response was observed in 188 patients (81%; 83 patients in the DR-MM group [79%] and 105 patients in the NDR-MM [82%]; P = .77). A near complete response or better was observed in 52 patients (22%; 25 patients in the DR-MM group [24%] and 27 patients in the NDR-MM group [21%]; P = .77). The median progression-free survival was 17.6 months (14.4 months in the DR-MM group and 18.2 months in the NDR-MM group), and the 2-year progression-free survival rate was 38% (35% in the DR-MM group and 40% in the NDR-MM group; P = .40). The median overall survival was 48 months (38.9 months in the DR-MM group and 56.6 months in the NDR-MM group), and the 2-year overall survival rate was 74% (71% in the DR-MM group and 76% in the NDR-MM group; P = .27). CONCLUSIONS: The current findings indicate that auto-HCT is an effective and safe therapy in patients with refractory multiple myeloma, including those who are refractory to IMiDs and PIs. Cancer 2017;123:3568-75. © 2017 American Cancer Society.

Long-term follow-up of patients receiving allogeneic stem cell transplant for chronic lymphocytic leukaemia: mixed T-cell chimerism is associated with high relapse risk and inferior survival.

There is limited information regarding the immunological predictors of post-allogeneic stem cell transplant (alloSCT) outcome in chronic lymphocytic leukaemia (CLL), such as mixed T-cell chimerism. We analysed 143 consecutive patients with relapsed/refractory CLL, transplanted between 2000 and 2012, to determine the prognostic relevance of mixed chimerism post-alloSCT and the ability of post-transplant immunomodulation to treat relapse. Mixed T-cell chimerism occurred in 50% of patients at 3 months and 43% at 6 months post-alloSCT; upon 3- and 6-month landmark analysis, this was associated with inferior progression-free survival (PFS) [Hazard ratio (HR) 1·93, P = 0·003 and HR 2·58, P < 0·001] and survival (HR 1·66, P = 0·05 and HR 2·17, P < 0·001), independent of baseline patient characteristics, and a lower rate of grade II-IV acute graft-versus-host disease (GHVD) (16% vs. 52%, P < 0·001). Thirty-three patients were treated with immunomodulation for relapse post-alloSCT (immunosuppression withdrawal, n = 6, donor lymphocyte infusion, n = 27); 17 achieved complete response (CR), which predicted superior PFS (53 months vs. 10 months, P < 0·001) and survival (117 months vs. 30 months, P = 0·006). Relapsed patients with mixed chimerism had inferior response to immunomodulation; conversion to full donor chimerism was highly correlated both with CR and with the development of severe acute GVHD, which was fatal in 3/8 patients. Novel therapeutic strategies are required for patients with mixed T-cell chimerism post-alloSCT for CLL.

Phase I study of cord blood-derived natural killer cells combined with autologous stem cell transplantation in multiple myeloma.

Multiple myeloma (MM) is a disease with known immune dysregulation. Natural killer (NK) cells have shown preclinical activity in MM. We conducted a first-in-human study of umbilical cord blood-derived (CB) NK cells for MM patients undergoing high dose chemotherapy and autologous haematopoietic stem cell transplantation (auto-HCT). Patients received lenalidomide (10 mg) on days -8 to -2, melphalan 200 mg/m2 on day -7, CB-NK cells on day -5 and auto-HCT on day 0. Twelve patients were enrolled, three on each of four CB-NK cell dose levels: 5 × 106 , 1 × 107 , 5 × 107 and 1 × 108 CB-NK cells/kg. Ten patients had either high-risk chromosomal changes or a history of relapsed/progressed disease. There were no infusional toxicities and no graft-versus-host disease. One patient failed to engraft due to poor autologous graft quality and was rescued with a back-up autologous graft. Overall, 10 patients achieved at least a very good partial response as their best response, including eight with near complete response or better. With a median follow-up of 21 months, four patients have progressed or relapsed, two of whom have died. CB-NK cells were detected in vivo in six patients, with an activated phenotype (NKG2D+ /NKp30+ ). These data warrant further development of this novel cellular therapy.

Ex vivo fucosylation of third-party human regulatory T cells enhances anti-graft-versus-host disease potency in vivo.

Adoptive therapy with regulatory T cells (Tregs) to prevent graft-versus-host disease (GVHD) would benefit from a strategy to improve homing to the sites of inflammation. We hypothesized that adding fucose to human Tregs, forming the Sialyl Lewis X moiety on P-selectin glycoprotein ligand-1, would improve their trafficking pattern. The selectin pathway recruiter, α-1,3-fucosyltransferase-VI enzyme, significantly increased Treg surface fucosylation (66% vs 8%). In a xenogenic GVHD mouse model, fucosylated Tregs showed prolonged periods of in vivo persistence. When given at a lower dose compared with the untreated Tregs, the murine recipients of fucosylated Tregs maintained weight, had ameliorated clinical GVHD, and improved survival (70% vs 30%; P < .0001). These preclinical data indicate that fucosylated human Tregs is an effective strategy for prevention of GVHD and, as such, warrants consideration for future clinical trials.

Enforced fucosylation of cord blood hematopoietic cells accelerates neutrophil and platelet engraftment after transplantation.

Delayed engraftment is a major limitation of cord blood transplantation (CBT), due in part to a defect in the cord blood (CB) cells' ability to home to the bone marrow. Because this defect appears related to low levels of fucosylation of cell surface molecules that are responsible for binding to P- and E-selectins constitutively expressed by the marrow microvasculature, and thus for marrow homing, we conducted a first-in-humans clinical trial to correct this deficiency. Patients with high-risk hematologic malignancies received myeloablative therapy followed by transplantation with 2 CB units, one of which was treated ex vivo for 30 minutes with the enzyme fucosyltransferase-VI and guanosine diphosphate fucose to enhance the interaction of CD34(+) stem and early progenitor cells with microvessels. The results of enforced fucosylation for 22 patients enrolled in the trial were then compared with those for 31 historical controls who had undergone double unmanipulated CBT. The median time to neutrophil engraftment was 17 days (range, 12-34 days) compared with 26 days (range, 11-48 days) for controls (P = .0023). Platelet engraftment was also improved: median was 35 days (range, 18-100 days) compared with 45 days (range, 27-120 days) for controls (P = .0520). These findings support ex vivo fucosylation of multipotent CD34(+) CB cells as a clinically feasible means to improve engraftment efficiency in the double CBT setting. The trial is registered to www.clinicaltrials.gov as #NCT01471067.

Inpatient vs outpatient autologous hematopoietic stem cell transplantation for multiple myeloma.

BACKGROUND: High-dose chemotherapy and autologous hematopoietic stem cell transplantation (auto-HCT) are commonly performed for multiple myeloma (MM) patients and may be as safe in the outpatient setting as in the inpatient setting. METHODS: We performed a single-center retrospective analysis of all MM patients undergoing auto-HCT between January 2008 and December 2012. We categorized patients as outpatient vs inpatient auto-HCT and compared clinical characteristics and outcomes between the groups. RESULTS: One thousand and forty-six patients were included (669 inpatients, 377 outpatients). Patients transplanted as outpatients were significantly younger (58 [34-78] vs 62 [31-82], P < .001) and more likely to have an hematopoietic stem cell comorbidity index (HCT-CI) score <2 (P = .003) and creatinine <2 (P < .001). There were no differences in treatment-related mortality (TRM) but the inpatient group experienced significantly more grade 2-5 (P = .003) and grade 3-5 (P = .003) adverse events (AEs). 2 year progression-free survival (PFS) was significantly longer in the outpatient group (60% vs 50%, HR =HR 0.7, 95% CI 0.6-0.9, P = .005). 2 year OS was also longer in the outpatient group (83% vs 77%, HR 0.6, 95% CI 04-0.9, P = .01). CONCLUSION: Outpatient auto-HCT can be safely performed for selected patients with MM. Differences in outcomes are likely related to baseline clinical characteristics rather than choice of treatment setting.

Clinical outcomes in adult patients with aplastic anemia: A single institution experience.

Newer treatment modalities are being investigated to improve upon historical outcomes with standard immunosuppressive therapy (IST) in aplastic anemia (AA). We analyzed outcomes of adult patients with AA treated with various combinatorial anti-thymoglobulin-based IST regimens in frontline and relapsed/refractory (R/R) settings. Pretreatment and on-treatment clinical characteristics were analyzed for relationships to response and outcome. Among 126 patients reviewed, 95 were treatment-naïve (TN) and 63, R/R (including 32 from the TN cohort); median ages were 49 and 50 years, respectively. Overall survival (OS) was superior in IST responders (P < .001). Partial response to IST was associated with shorter relapse-free survival (RFS), as compared with complete response (P = .03). By multivariate analysis, baseline platelet and lymphocyte count predicted for IST response at 3 and 6 months, respectively. While additional growth factor interventions led to faster count recovery, there were no statistically significant differences in RFS or OS across the various frontline IST regimens (i.e., with/without G-CSF or eltrombopag). While marrow cellularity did not correlate with peripheral-blood counts at 3 months, cytomorphological assessment revealed dyspoietic changes in all nonresponders with hypercellular-marrow indices. Covert dysplasia, identified through early bone marrow assessment, has implications on future therapy choices after IST failure. Salvage IST response depended upon prior response to ATG: prior responders (46%) vs. primary refractory (0%) (P < .01). In the R/R setting, there was no survival difference between IST and allogeneic stem cell transplant groups, with a trend toward superior OS in the former. Transplant benefits in the R/R setting may be underrealized due to transplant-related mortality.

Pure Red Cell Aplasia in Major ABO-Mismatched Allogeneic Hematopoietic Stem Cell Transplantation Is Associated with Severe Pancytopenia.

In major ABO-mismatched allogeneic hematopoietic stem cell transplantation (HSCT) persistence of antidonor isohemagglutinins leads to pure red cell aplasia (PRCA). To investigate severe pancytopenia noted in a previous study of PRCA, we analyzed all major ABO-mismatched HSCT between January 2003 and December 2012. Of 83 PRCA patients, 13 (16%) had severe pancytopenia. Severe pancytopenia was defined as an absolute neutrophil count (ANC) < 1.5 K/µL or requiring granulocyte colony-stimulating factor, platelets < 50 K/µL or transfusion dependent, and PRCA with RBC transfusion dependence at post-transplant day 90. In 6 patients (46%) severe pancytopenia resolved after PRCA resolution. Two patients (15%) received a second transplant because of persistent pancytopenia/secondary graft failure, 1 (8%) died from secondary graft failure despite a stem cell boost, 1 (8%) did not recover his platelet counts despite RBC/ANC recovery, and 3 patients (23%) died from disease relapse. We found that severe pancytopenia is frequently associated with PRCA in 16% of major ABO-incompatible HSCT with a higher incidence in males and pancytopenia resolved with resolution of PRCA in 46% of patients.

Prolonged survival with a longer duration of maintenance lenalidomide after autologous hematopoietic stem cell transplantation for multiple myeloma.

BACKGROUND: Although lenalidomide maintenance therapy has demonstrated improved outcomes after autologous hematopoietic stem cell transplantation (auto-HCT) for patients with multiple myeloma (MM), the impact of the duration of this therapy is not clearly known. METHODS: This study retrospectively analyzed all MM patients who were placed on maintenance lenalidomide after auto-HCT between January 2007 and December 2013. Progression-free survival (PFS) and overall survival (OS) were analyzed in multivariate Cox proportional hazards regression models that included the duration of maintenance as a time-dependent covariate. RESULTS: Of the 464 patients identified, 46% initiated therapy early (<4 months after auto-HCT). The median PFS and OS were 38 and 78 months, respectively. Improvements in PFS (hazard ratio [HR], 0.13; 95% confidence interval [CI], 0.04-0.38; P < .001) and OS (HR, 0.09; 95% CI, 0.03-0.26; P < .001) were seen for those on maintenance for >2 years versus those on maintenance for ≤2 years. For those on maintenance for >3 versus those on maintenance for ≤3 years, this trend continued with improvements seen in PFS (HR, 0.02; 95% CI, 0.00-0.44; P = .012) and OS (HR, 0.05; 95% CI, 0.00-0.83; P = .037). The incidence of second primary malignancies (SPMs) in the entire cohort was 3%. No differences were seen in survival between early and late initiators of maintenance lenalidomide. CONCLUSIONS: A longer duration of maintenance therapy was associated with longer survival. The incidence of SPMs was low, and they were not associated with the duration of maintenance. The timing of the initiation of maintenance had no effect on survival. Cancer 2016;122:3831-3837. © 2016 American Cancer Society.