Chimeric antigen receptor and bispecific T-cell engager therapies in multiple myeloma patients with prior allogeneic transplantation.

Chimeric antigen receptor T-cell (CAR-T) therapy and bispecific T-cell engagers (BsAb) have emerged as promising immunotherapeutic modalities in patients with relapsed and/or refractory multiple myeloma (RRMM). However, there is limited data on the safety and efficacy of CAR-T and BsAb therapies in MM patients with a prior history of allogeneic transplantation (allo-HCT). Thirty-three MM patients with prior allo-HCT received CAR-T (n = 24) or BsAb (n = 9) therapy. CAR-T therapy demonstrated an ORR of 92% (67% ≥ CR), and 73% were MRD negative. BsAb therapy resulted in an ORR of 44% (44% ≥ CR) and 44% MRD negative. Safety analysis showed grade ≥3 AEs in 92% of CAR-T and 56% of BsAb patients. Cytokine release syndrome (CRS) occurred in 83% of CAR-T and 78% of BsAb recipients, while immune effector cell-associated neurotoxicity syndrome (ICANS) was observed in three CAR-T patients. Infections of grade ≥3 were reported in 50% of CAR-T and 44% of BsAb recipients. No exacerbation of graft-versus-host disease occurred except in one BsAb recipient. CAR-T and BsAb therapies appear to be feasible, safe and provide deep and durable responses in MM patients with prior allo-HCT.

HLA-haploidentical vs matched unrelated donor transplants with posttransplant cyclophosphamide-based prophylaxis.

Posttransplant cyclophosphamide (PTCy) graft-versus-host disease (GVHD) prophylaxis has enabled haploidentical (Haplo) transplantation to be performed with results similar to those after matched unrelated donor (MUD) transplantation with traditional prophylaxis. The relative value of transplantation with MUD vs Haplo donors when both groups receive PTCy/calcineurin inhibitor/mycophenolate GVHD prophylaxis is not known. We compared outcomes after 2036 Haplo and 284 MUD transplantations with PTCy GVHD prophylaxis for acute leukemia or myelodysplastic syndrome in adults from 2011 through 2018. Cox regression models were built to compare outcomes between donor types. Recipients of myeloablative and reduced-intensity regimens were analyzed separately. Among recipients of reduced-intensity regimens, 2-year graft failure (3% vs 11%), acute grades 2 to 4 GVHD (hazards ratio [HR], 0.70; P = .022), acute grades 3 and 4 GVHD (HR, 0.41; P = .016), and nonrelapse mortality (HR, 0.43; P = .0008) were lower after MUD than with Haplo donor transplantation. Consequently, disease-free (HR, 0.74; P = .008; 55% vs 41%) and overall (HR, 0.65; P = .001; 67% vs 54%) survival were higher with MUD than with Haplo transplants. Among recipients of myeloablative regimens, day-100 platelet recovery (95% vs 88%) was higher and grades 3 and 4 acute (HR, 0.39; P = .07) and chronic GVHD (HR, 0.66; P = .05) were lower after MUD than with Haplo donor transplantation. There were no differences in graft failure, relapse, nonrelapse mortality, and disease-free and overall survival between donor types with myeloablative conditioning regimens. These data extend and confirm the importance of donor-recipient HLA matching for allogeneic transplantation. A MUD is the preferred donor, especially for transplantations with reduced-intensity conditioning regimens.

Association between the choice of the conditioning regimen and outcomes of allogeneic hematopoietic cell transplantation for myelofibrosis.

Allogeneic hematopoietic cell transplantation (allo-HCT) remains the only curative treatment for myelofibrosis. However, the optimal conditioning regimen either with reduced-intensity conditioning (RIC) or myeloablative conditioning (MAC) is not well known. Using the Center for International Blood and Marrow Transplant Research database, we identified adults aged ≥18 years with myelofibrosis undergoing allo-HCT between 2008-2019 and analyzed the outcomes separately in the RIC and MAC cohorts based on the conditioning regimens used. Among 872 eligible patients, 493 underwent allo-HCT using RIC (fludarabine/ busulfan n=166, fludarabine/melphalan n=327) and 379 using MAC (fludarabine/busulfan n=247, busulfan/cyclophosphamide n=132). In multivariable analysis with RIC, fludarabine/melphalan was associated with inferior overall survival (hazard ratio [HR]=1.80; 95% confidenec interval [CI]: 1.15-2.81; P=0.009), higher early non-relapse mortality (HR=1.81; 95% CI: 1.12-2.91; P=0.01) and higher acute graft-versus-host disease (GvHD) (grade 2-4 HR=1.45; 95% CI: 1.03-2.03; P=0.03; grade 3-4 HR=2.21; 95%CI: 1.28-3.83; P=0.004) compared to fludarabine/busulfan. In the MAC setting, busulfan/cyclophosphamide was associated with a higher acute GvHD (grade 2-4 HR=2.33; 95% CI: 1.67-3.25; P<0.001; grade 3-4 HR=2.31; 95% CI: 1.52-3.52; P<0.001) and inferior GvHD-free relapse-free survival (GRFS) (HR=1.94; 95% CI: 1.49-2.53; P<0.001) as compared to fludarabine/busulfan. Hence, our study suggests that fludarabine/busulfan is associated with better outcomes in RIC (better overall survival, lower early non-relapse mortality, lower acute GvHD) and MAC (lower acute GvHD and better GRFS) in myelofibrosis.

Promise and pitfalls of allogeneic chimeric antigen receptor therapy in plasma cell and lymphoid malignancies.

Chimeric antigen receptor (CAR) T-cell therapy is a promising immunotherapy in haematological malignancies. However, the currently approved products are generated from autologous T cells that require orchestration of several logistically complex steps, which include patient eligibility, apheresis capability, complex manufacturing processes and shipping logistics. Use of third-party donor-derived (allogeneic) effector cells that allows the generation of 'off-the-shelf" CAR T cells (allo-CAR) could circumvent many of the problems associated with autologous CAR T-cell therapy. Several allogeneic products are entering clinical trials, and though early, the results look promising. The recognised potential benefits of allo-CAR do not come without significant challenges, that must be overcome for their widespread use. Alloreactivity, i.e. graft-versus-host disease (GVHD), and rejection of donor T cells is one of the major barriers, while other potential barriers include immunogenicity, unknown in vivo persistence, and CAR T-cell yield. In the present review, we provide a comprehensive review of the challenges associated with autologous CAR, the benefits and potential challenges associated with allo-CAR. Finally, we review the available platforms for allo-CAR for B-cell and plasma cell malignancies.

Does recipient body mass index inform donor selection for allogeneic haematopoietic cell transplantation?

It is not known whether obesity has a differential effect on allogeneic haematopoietic cell transplantation outcomes with alternative donor types. We report the results of a retrospective registry study examining the effect of obesity [body mass index (BMI) > 30] on outcomes with alternative donors (haploidentical related donor with two or more mismatches and receiving post-transplant cyclophosphamide [haplo] and cord blood (CBU)] versus matched unrelated donor (MUD). Adult patients receiving haematopoietic cell transplantation for haematologic malignancy (2013-2017) (N = 16 182) using MUD (n = 11 801), haplo (n = 2894) and CBU (n = 1487) were included. The primary outcome was non-relapse mortality (NRM). The analysis demonstrated a significant, non-linear interaction between pretransplant BMI and the three donor groups for NRM: NRM risk was significantly higher with CBU compared to haplo at BMI 25-30 [hazard ratio (HR) 1.66-1.71, p < 0.05] and MUD transplants at a BMI of 25-45 (HR, 1.61-3.47, p < 0.05). The results demonstrated that NRM and survival outcomes are worse in overweight and obese transplant recipients (BMI ≥ 25) with one alternative donor type over MUD, although obesity does not appear to confer a uniform differential mortality risk with one donor type over the other. BMI may serve as a criterion for selecting a donor among the three (MUD, haplo and CBU) options, if matched sibling donor is not available.

Randomized multicenter trial of sirolimus vs prednisone as initial therapy for standard-risk acute GVHD: the BMT CTN 1501 trial.

Clinical- and biomarker-based tools may identify a lower-risk acute graft-versus-host disease (GVHD) population amenable to novel, reduced-intensity treatments. Previous data suggest sirolimus may rival standard of care prednisone. We conducted a National Heart, Lung, and Blood Institute/National Cancer Institute-funded Blood and Marrow Transplant Clinical Trials Network multicenter, open-label, randomized phase 2 trial to estimate the difference in day 28 complete response (CR)/partial response (PR) rates for sirolimus vs prednisone as initial treatment of patients with standard risk (SR) acute GVHD as defined by the Minnesota (MN) GVHD Risk Score and Ann Arbor (AA1/2) biomarker status. A total of 127 MN-SR patients were randomized (1:1), and 122 were AA1/2 (sirolimus, n = 58; prednisone, n = 64). Others were AA3 (n = 4), or AA status missing (n = 1). The day 28 CR/PR rates were similar for sirolimus 64.8% (90% confidence interval [CI], 54.1%-75.5%) vs 73% (90% CI, 63.8%-82.2%) for prednisone. The day 28 rate of CR/PR with prednisone ≤0.25 mg/kg/day was significantly higher for sirolimus than prednisone (66.7% vs 31.7%; P < .001). No differences were detected in steroid-refractory acute GVHD, disease-free survival, relapse, nonrelapse mortality, or overall survival. Sirolimus was associated with reduced steroid exposure and hyperglycemia, reduced grade 2 to 3 infections, improvement in immune suppression discontinuation and patient-reported quality of life, and increased risk for thrombotic microangiopathy. For patients with clinical- and biomarker-based SR acute GVHD, sirolimus demonstrates similar overall initial treatment efficacy as prednisone. In addition, sirolimus therapy spares steroid exposure and allied toxicity, does not compromise long-term survival outcomes, and is associated with improved patient-reported quality of life. This trial was registered at www.clinicaltrials.gov as #NCT02806947.

Impact of autologous hematopoietic cell transplantation on disease burden quantified by next-generation sequencing in multiple myeloma treated with quadruplet therapy.

The incremental impact of autologous hematopoietic cell transplantation (AHCT) on disease burden with quadruplet induction in newly diagnosed multiple myeloma (NDDM) can be reappraised with the serial assessment of minimal residual disease (MRD). We describe the impact of AHCT on MM burden assessed by next-generation sequencing (NGS) for patients enrolled in a clinical trial utilizing quadruplet induction, AHCT, followed by MRD-adapted consolidation. We describe quantitative changes in MRD burden with AHCT and explore patient and disease features influencing the magnitude of MRD reduction with AHCT. Among 123 included patients, 109 underwent AHCT and had MRD assessment pre and post AHCT. Forty percent achieved MRD < 10-5 post-induction, increasing to 70% after AHCT. Of the 65 patients (60%) who remained MRD positive post-induction, 54 (83%) had a reduction in MRD burden with AHCT. The median reduction in MRD with AHCT was 1.10 log10 (range, -1.26 to 3.41). Patients with high-risk cytogenetic abnormalities (HRCA) had greater reduction in MRD burden (p = .02) after AHCT. Median relative reduction was 0.91 log10 (range, -0.75 to 2.14), 1.26 log10 (range, -0.21 to 3.26) and 1.34 log10 (range, -1.28 to 3.41) for patients with 0, 1 and 2+ HRCA, respectively. The presence of HRCA was the only factor associated with greater than 1 log10 reduction in MRD burden with AHCT. Serial NGS MRD demonstrates the incremental effect of AHCT in MM marrow burden in the context of quadruplet induction, particularly in high-risk MM.

Monoclonal gammopathy of renal significance (MGRS): Real-world data on outcomes and prognostic factors.

Monoclonal gammopathy of renal significance (MGRS) is a recognized clinical entity. Literature regarding treatment and its outcomes in MGRS is sparse due to the rarity and misdiagnosis of MGRS. We retrospectively analyzed 280 adults with an MGRS diagnosis from 2003 to 2020 across 19 clinical centers from 12 countries. All cases required renal biopsy for the pathological diagnosis of MGRS. Amyloidosis-related to MGRS (MGRS-A) was present in 180 patients; nonamyloidosis MGRS (MGRS-NA), including a broad spectrum of renal pathologies, was diagnosed in 100 patients. The median overall survival in the studied cohort was 121.0 months (95% CI: 105.0-121.0). Patients with MGRS-A had a shorter overall survival than patients with MGRS-NA (HR = 0.41, 95%CI: 0.25-0.69; p = 0.0007). Both hematologic and renal responses were associated with longer survival. Achievement of ≥VGPR was generally predictive of a renal response (OR = 8.03 95%CI: 4.04-115.96; p < 0.0001), one-fourth of patients with ≥VGPR were renal nonresponders. In MGRS-A, factors associated with poor prognosis included elevated levels of creatinine, beta-2-microglobulin, and hemodialysis at diagnosis. In MGRS-NA, only age >65 years was associated with increased risk of death. Treatments provided similar hematologic response rates in both types of MGRS. Autologous stem cell transplantation led to better response than other treatments. This multicenter and international effort is currently the largest report on MGRS.

Exploring health behaviors and the feasibility of a lifestyle intervention for patients with multiple myeloma.

PURPOSE: Multiple myeloma (MM) is the second most common hematologic malignancy in the USA, with higher rates observed in older adults and African Americans (AA). Survivors experience fatigue, bone pain, reduced functioning, and obesity, highlighting the value of developing lifestyle interventions for this diverse group. This study explores lifestyle behaviors and supportive care needs to inform future programs tailored to the MM community. METHODS: MM survivors, ≥ 100 days post autologous stem cell transplant (ASCT) with a BMI ≥ 20 kg/m2, were recruited from two university hospitals. Diet, physical activity, and quality of life (QOL) were measured using validated measures. Qualitative interviews gathered information on survivorship needs and interests related to supportive interventions. Quantitative data was analyzed using descriptive statistics; qualitative data were analyzed using deductive strategies. RESULTS: Seveny-two MM survivors participated (65% white, 35% black). Participants were 62.5 ± 15.8 years of age. Fifty percent were classified as obese and 65% were insufficiently active. Participants reported diets high in added sugars and saturated fats. QOL measures indicated clinically significant challenges in physical and sexual function. Most (87%) were interested in a lifestyle program. Predominant themes regarding survivors' desires for a lifestyle program included social support, guided exercise, meal preparation support, and disease management information. CONCLUSION: This study demonstrates the need for and interest in lifestyle change support among a racially diverse sample of MM survivors. Interventions that are group-based, target knowledge gaps, social connections, accountability, and provide structured framework with professional instruction will best address the needs of this survivor population.

Rap1A, Rap1B, and ß-Adrenergic Signaling in Autologous HCT: A Randomized Controlled Trial of Propranolol.

Successful hematopoietic cell transplantation (HCT) depends on rapid engraftment of the progenitor and stem cells that will reestablish hematopoiesis. Rap1A and Rap1B are two closely related small GTPases that may affect platelet and neutrophil engraftment during HCT through their roles in cell adhesion and migration. ß-adrenergic signaling may regulate the participation of Rap1A and Rap1B in engraftment through their inhibition or activation. We conducted a correlative study of a randomized controlled trial evaluating the effects of the nonselective ß-antagonist propranolol on expression and prenylation of Rap1A and Rap1B during neutrophil and platelet engraftment in 25 individuals receiving an autologous HCT for multiple myeloma. Propranolol was administered for 1 week prior to and 4 weeks following HCT. Blood was collected 7 days (baseline) and 2 days (Day -2) before HCT, and 28 days after HCT (Day +28). Circulating polymorphonuclear cells (PMNC) were isolated and analyzed via immunoblotting to determine levels of prenylated and total Rap1A versus Rap1B. Twelve participants were randomized to the intervention and 13 to the control. Rap1A expression significantly correlated with Rap1B expression. Rap1B expression significantly correlated with slower platelet engraftment; however, this association was not observed in the propranolol-treated group. There were no significant associations between neutrophil engraftment and Rap1A or Rap1B expression. Post hoc exploratory analyses did not reveal an association between social health variables and Rap1A or Rap1B expression. This study identifies a greater regulatory role for Rap1B than Rap1A in platelet engraftment and suggests a possible role for ß-adrenergic signaling in modulating Rap1B function during HCT.

African Americans with translocation t(11;14) have superior survival after autologous hematopoietic cell transplantation for multiple myeloma in comparison with Whites in the United States.

BACKGROUND: Multiple myeloma (MM) with the translocation t(11;14) may have inferior outcomes in comparison with other standard-risk MM, and it has been suggested to portend a worse prognosis in African Americans in comparison with Whites. This study used the Center for International Blood and Marrow Transplant Research (CIBMTR) database to examine the impact of t(11;14) on the clinical outcomes of patients with MM of African American and White descent. METHODS: This study evaluated 3538 patients who underwent autologous hematopoietic cell transplantation (autoHCT) for MM from 2008 to 2016 and were reported to the CIBMTR. Patients were analyzed in 4 groups: African Americans with t(11;14) (n = 117), African Americans without t(11;14) (n = 968), Whites with t(11;14) (n = 266), and Whites without t(11;14) (n = 2187). RESULTS: African Americans with t(11;14) were younger, had lower Karnofsky scores, and had more advanced stage MM with a higher Hematopoietic Cell Transplantation-Comorbidity Index (HCT-CI). Fewer African Americans with t(11;14) (21%) had a coexistent high-risk marker in comparison with Whites with t(11;14) (27%). In a multivariate analysis, race and t(11;14) had no association with progression-free survival. However, overall survival was superior among African Americans with t(11;14) in comparison with Whites with t(11;14) (hazard ratio, 0.53; 95% confidence interval, 0.30-0.93; P = .03). Survival was also associated with female sex, stage, time from diagnosis to transplant, a low HCT-CI, and receipt of maintenance. CONCLUSIONS: Race may have a differential impact on the survival of patients with t(11;14) MM who undergo autoHCT and needs to be further studied.

The Effect of Granulocyte Colony-Stimulating Factor Use on Hospital Length of Stay after Allogeneic Hematopoietic Cell Transplantation: A Retrospective Multicenter Cohort Study.

Granulocyte colony-stimulating factor (G-CSF) is administered after allogeneic hematopoietic cell transplantation (HCT) to aid neutrophil recovery. We compared the effect of empiric G-CSF administration on the duration of index inpatient hospitalization stay after HCT for patients aged ≥18 years with a hematologic malignancy. G-CSF was considered empiric if administered between day -3 and day +6 in relation to graft infusion. We studied 3562 HCTs (1487 HLA-matched sibling donor HCTs and 2075 HLA-matched unrelated donor HCTs) between 2007 and 2016. Three hundred and thirteen (21%) recipients of HLA-matched sibling donor HCT and 417 (20%) recipients of HLA-matched unrelated donor HCT received empiric G-CSF therapy. The effect of G-CSF therapy on the index hospitalization stay was examined in generalized linear models (GLMs) with adjustment for other patient, disease, and transplantation characteristics and acute graft-versus-host disease and infection post-transplantation. The duration of index hospitalization by treatment group did not differ for HLA-matched sibling donor HCT but was shorter with G-CSF for HLA-matched unrelated donor HCT (15 days versus 19 days; P < .001). Our GLMs confirmed shorter hospitalization with the use of G-CSF therapy for HLA-matched unrelated donor HCT (P = .01). G-CSF therapy was not associated with early survival for either donor type, and there was no benefit or disadvantage of giving G-CSF to promote neutrophil recovery.

Propylene Glycol-Free Melphalan versus PG-Melphalan as Conditioning for Autologous Hematopoietic Cell Transplantation for Myeloma.

High-dose melphalan (Mel) conditioning before autologous hematopoietic cell transplantation (autoHCT) is standard of care for patients with transplantation-eligible multiple myeloma. The traditional lyophilized Mel formulation has inadequate solubility and stability after reconstitution, leading to the use of propylene glycol (PG) as a solubilizing agent. A newer PG-free Mel preparation (Evomela) uses beta cyclodextrin captisol as a solubilizing agent and was approved by the United States Food and Drug Administration as a conditioning agent based on a single-phase IIb study showing bioequivalence. We compared the outcomes of consecutive patients with myeloma undergoing autoHCT using the 2 formulations of Mel for conditioning as our center switched from using the older formulation (PG-Mel) to the newer one (PGF-Mel). Of 294 autoHCT recipients, 162 received PG-Mel conditioning and 132 received PGF-Mel conditioning. The PGF-Mel group was older and had a lower average Karnofsky Performance Status score. PGF-Mel was associated with faster neutrophil recovery (median, 12 days versus 13 days; P < .001), fewer grade 3-4 infections within 30 days of autoHCT (1.5% versus 8.0%; P = .048), and a lower 30-day rehospitalization rate (6.8% versus 17.9%; P = .04), as confirmed by propensity-weighted analysis. No significant between-group differences were detected in mucositis, organ toxicity, myeloma response, or 100-day mortality.

Utilization and Cost Implications of Hematopoietic Progenitor Cells Stored for a Future Salvage Autologous Transplantation or Stem Cell Boost in Myeloma Patients.

Autologous hematopoietic cell transplantation (autoHCT) is a standard initial treatment for multiple myeloma (MM). Consensus guidelines recommend collecting sufficient hematopoietic progenitor cells (HPCs) for 2 autoHCTs in all eligible patients. Despite a lack of published data on the utilization of HPCs stored for future use, it is common practice across transplantation programs to collect enough HPCs for 2 autoHCTs in MM patients. In this single-center retrospective study, we analyzed the utilization of HPCs collected and stored at the time of first autoHCT in patients with MM, along with the cost implications of HPC collection targets sufficient for 2 transplantations. In a cohort of 400 patients (median age, 63 years; range, 22 to 79 years), after a median follow-up of 50.4 months, 197 patients had relapsed and 36 had received HPC infusion as salvage autoHCT (n = 29) and/or HPC boost (n = 8). In this cohort, a median CD34+ cell dose of 4.3 × 106/kg (range, 1.1 to 12.94.3 × 106/kg) was used for first autoHCT, and a median of 4.4 × 106/kg (range, 1.0 to 20.2× 106/kg) CD34+ cells were stored for future use. At 6 years after the first autoHCT, the estimated cumulative incidence of salvage autoHCT was 12.0% without HPC boost and 13.9% with HPC boost. HPC utilization was significantly higher in the 60- to 64-year age group, whereas no patients who were age ≥70 years at the time of first autoHCT received salvage autoHCT. Using the CD34+ cell dose infused during the first autoHCT as the cutoff for individual patients, the estimated mean additional cost of HPC collection intended for subsequent use (over and above the HPCs used for first autoHCT) was $10,795 ($4.32 million for the entire cohort), an estimated 14% of which (ie, $583,600) was actually used up in salvage autoHCT by 6 years from first autoHCT. In conclusion, our results suggest the need for reappraisal of HPC collection targets for salvage autoHCT and argue against HPC collection and storage for salvage autoHCT in patients age ≥70 years at the time of first autoHCT.

Relapse after Allogeneic Hematopoietic Cell Transplantation for Multiple Myeloma: Survival Outcomes and Factors Influencing Them.

Many patients with multiple myeloma (MM) eventually relapse even after allogeneic hematopoietic cell transplantation (alloHCT) for curative intent. Over the past decade, outcomes for patients with MM have improved significantly with the availability of new therapies, including next-generation proteasome inhibitors, immunomodulatory agents, and, more recently, monoclonal antibodies. Although several published studies have evaluated the outcomes of alloHCT for MM, the data on survival outcomes in patients with MM experiencing disease relapse following alloHCT are limited. In addition, the predictors for postrelapse survival in these patients are not known. In this study, we examined the outcomes of a single-center cohort of 60 patients with MM who experienced relapse or progression after alloHCT. In addition, we evaluated the use of salvage regimens for treatment of relapsed MM and analyzed the predictors for improved postrelapse survival. After a median follow-up of 2.2 years from the time of relapse, the median duration of postrelapse survival was 1.8 years (95% confidence interval [CI], 1.2 to 5.0 years). Patients received a median of 3 lines of therapy (range, 0 to 10) for treatment of MM beyond the post-alloHCT relapse/progression. Multivariate analysis identified cytogenetic risk (standard risk versus high risk; hazard ratio [HR], .34; P = .01), time to relapse after alloHCT (>12 months versus ≤12 months: HR, .41; P = .04), and occurrence of acute graft-versus-host disease (GVHD) before relapse (GVHD versus no GVHD: HR, 2.89; P = .01) significantly affected postrelapse survival. These data illustrate that long-term myeloma control and survival is attainable in those relapsing/progressing after alloHCT and suggest that the synergism between novel therapies and the allogeneic immune platform is the key to improved survival in this high-risk patient population.

Graft Cryopreservation Does Not Impact Overall Survival after Allogeneic Hematopoietic Cell Transplantation Using Post-Transplantation Cyclophosphamide for Graft-versus-Host Disease Prophylaxis.

The COVID-19 pandemic has created significant barriers to timely donor evaluation, cell collection, and graft transport for allogeneic hematopoietic stem cell transplantation (allo-HCT). To ensure availability of donor cells on the scheduled date of infusion, many sites now collect cryopreserved grafts before the start of pretransplantation conditioning. Post-transplantation cyclophosphamide (ptCY) is an increasingly used approach for graft-versus-host disease (GVHD) prophylaxis, but the impact of graft cryopreservation on the outcomes of allo-HCT using ptCY is not known. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared the outcomes of HCT using cryopreserved versus fresh grafts in patients undergoing HCT for hematologic malignancy with ptCY. We analyzed 274 patients with hematologic malignancy undergoing allo-HCT between 2013 and 2018 with cryopreserved grafts and ptCY. Eighteen patients received bone marrow grafts and 256 received peripheral blood stem cell grafts. These patients were matched for age, graft type, disease risk index (DRI), and propensity score with 1080 patients who underwent allo-HCT with fresh grafts. The propensity score, which is an assessment of the likelihood of receiving a fresh graft versus a cryopreserved graft, was calculated using logistic regression to account for the following: disease histology, Karnofsky Performance Score (KPS), HCT Comorbidity Index, conditioning regimen intensity, donor type, and recipient race. The primary endpoint was overall survival (OS). Secondary endpoints included acute and chronic graft-versus-host disease (GVHD), non-relapse mortality (NRM), relapse/progression and disease-free survival (DFS). Because of multiple comparisons, only P values <.01 were considered statistically significant. The 2 cohorts (cryopreserved and fresh) were similar in terms of patient age, KPS, diagnosis, DRI, HCT-CI, donor/graft source, and conditioning intensity. One-year probabilities of OS were 71.1% (95% confidence interval [CI], 68.3% to 73.8%) with fresh grafts and 70.3% (95% CI, 64.6% to 75.7%) with cryopreserved grafts (P = .81). Corresponding probabilities of OS at 2 years were 60.6% (95% CI, 57.3% to 63.8%) and 58.7% (95% CI, 51.9% to 65.4%) (P = .62). In matched-pair regression analysis, graft cryopreservation was not associated with a significantly higher risk of mortality (hazard ratio [HR] for cryopreserved versus fresh, 1.05; 95% CI, .86 to 1.29; P = .60). Similarly, rates of neutrophil recovery (HR, .91; 95% CI, .80 to 1.02; P = .12), platelet recovery (HR, .88; 95% CI, .78 to 1.00; P = .05), grade III-IV acute GVHD (HR, .78; 95% CI, .50 to 1.22; P = .27), NRM (HR, 1.16; 95% CI, .86 to 1.55; P = .32) and relapse/progression (HR, 1.21; 95% CI, .97 to 1.50; P = .09) were similar with cryopreserved grafts versus fresh grafts. There were somewhat lower rates of chronic GVHD (HR, 78; 95% CI, .61 to .99; P = .04) and DFS (HR for treatment failure, 1.19; 95% CI, 1.01 to 1.29; P = .04) with graft cryopreservation that were of marginal statistical significance after adjusting for multiple comparisons. Overall, our data indicate that graft cryopreservation does not significantly delay hematopoietic recovery, increase the risk of acute GVHD or NRM, or decrease OS after allo-HCT using ptCY.

Severity of Cytokine Release Syndrome and Its Association with Infections after T Cell-Replete Haploidentical Related Donor Transplantation.

An increased risk of infections has been described after T cell-replete haploidentical cell transplantation (haploHCT). Cytokine release syndrome (CRS) after haploHCT is a known phenomenon, but the impact of CRS severity on the risk of infections remains unexplored. We retrospectively evaluated 78 consecutive adult haploHCT recipients from 2012 to 2018 for the development of CRS (graded based on the criteria of Lee et al) and examined the incidence and mortality due to infections in correlation with CRS severity. In our study cohort, which was stratified into 3 groups by severity of CRS, 80% of the patients developed infections within 180 days of HCT. Significantly higher proportions of patients with CRS grade 2 (89%) and grade ≥3 (90%) than patients with CRS grade 0-1 (68%) had at least 1 infection in the first 100 days (P = .04). Bloodstream infections (BSIs) were seen more frequently in patients with CRS grade 2 and grade ≥3 in the first 6 months. Multivariable analysis for time to infection showed that CRS grade ≥3 was independently associated with an elevated risk of any infection compared with CRS grade 0-1 (hazard ratio [HR], 3.05; P = .007). CRS grade ≥3 was also associated with a higher hazard of viral (HR, 3.42; P = .04) and bacterial infections (HR, 2.83; P = .03) compared with CRS grade 0-1. After adjusting for time to neutrophil engraftment as a time-dependent covariate, CRS grade ≥3 still had a significant effect on viral infections (HR, 2.49; P = .03), but not on bacterial infections (HR, 1.32; P = .57). CRS grade was also a significant predictor for infection density (overall, bacterial, and viral). The incidence of infection-related mortality by day +100 was higher in patients with severe CRS. Severe CRS developing after post-transplantation cyclophosphamide-based haploHCT is independently associated with viral infections and an increased risk of bacterial infections, likely through delayed neutrophil engraftment.

Fludarabine/Busulfan Conditioning-Based Allogeneic Hematopoietic Cell Transplantation for Myelofibrosis: Role of Ruxolitinib in Improving Survival Outcomes.

Allogeneic hematopoietic cell transplantation (allo-HCT) is the only curative treatment modality for primary myelofibrosis (MF) and related myeloproliferative neoplasms. Older age at diagnosis and age-related comorbidities make most patients ineligible for allo-HCT, given concerns for nonrelapse mortality (NRM). Here we report the outcomes of 37 consecutive recipients of allo-HCT for MF performed at a single center between 2009 and 2018 with a standardized institutional protocol. Most patients received ruxolitinib before HCT (n = 32), and those with splenomegaly >22 cm received pretransplantation splenic irradiation. The median age at HCT was 60 years (range, 40 to 74 years), and 68% of the cohort carried a JAK2 driver mutation. All patients received fludarabine/busulfan-based conditioning; 22 patients (59%) received a reduced-intensity conditioning regimen. All patients received peripheral blood grafts, from a matched sibling donor in 16 patients (43%), an unrelated donor in 20 patients, and a haploidentical-related donor in 1 patient. Sixty-one percent had a Hematopoietic Cell Transplantation Comorbidity Index ≥3, 40% had a Karnofsky Performance Status score <90, and 24% had a high-risk DIPSS Plus score. With a median follow-up of 40.2 months (range, 16.9 to 115 months), the 3-year overall survival and relapse-free survival were 81.1% (95% confidence interval [CI], 64.4% to 90.5%) and 78.4% (95% CI, 61.4% to 88.5%), respectively. Only 2 patients relapsed/progressed after transplant. NRM at 2 years was 16.2% (95% CI, 6.5% to 29.9%). All patients engrafted. Sixteen patients were treated with ruxolitinib post-transplantation for graft-versus-host disease, graft rejection/relapse, or persistent MF. These results suggest that pretransplantation ruxolitinib, fludarabine/busulfan-based conditioning, and splenic management are keys to improved transplantation outcomes in patients undergoing allo-HCT for MF.

Ixazomib for Chronic Graft-versus-Host Disease Prophylaxis following Allogeneic Hematopoietic Cell Transplantation.

Chronic graft-versus-host disease (cGVHD) is major cause of morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Ixazomib is an oral, second-generation, proteasome inhibitor that has been shown in preclinical models to prevent GVHD. We conducted a phase I/II trial in 57 patients to evaluate the safety and efficacy of ixazomib administration for cGVHD prophylaxis in patients undergoing allogeneic HCT. Oral ixazomib was administered on a weekly basis for a total of 4 doses, beginning days +60 through +90, to recipients of matched related donor (MRD, n = 25) or matched unrelated donor (MUD, n = 26) allogeneic HCT in phase II portion of the study, once the recommended phase II dose of 4 mg was identified in phase I (n = 6). All patients received peripheral blood graft and standard GVHD prophylaxis of tacrolimus and methotrexate. Ixazomib administration was safe and well tolerated, with thrombocytopenia, leukopenia, gastrointestinal complaints, and fatigue the most common adverse events (>10%). In phase II (n = 51), the cumulative incidence of cGVHD at 1 year was 36% (95% confidence interval [CI], 19% to 54%) in the MRD cohort and 39% (95% CI, 21% to 56%) in the MUD cohort. One-year cumulative incidence of nonrelapse mortality (NRM) and relapse was 0% and 20% (95% CI, 8% to 36%) in the MRD cohort, respectively. In the MUD cohort, the respective NRM and relapse rates were 4% (0% to 16%) and 34% (17% to 52%). The outcomes on the study were compared post hoc with contemporaneous matched Center for International Blood and Marrow Transplant Research (CIBMTR) controls. This post hoc analysis showed no significant improvement in cGVHD rates in both the MRD (hazard ratio [HR] = 0.85, P = .64) or MUD cohorts (HR = 0.68, P = .26) on the study compared with CIBMTR controls. B cell activating factor plasma levels were significantly higher after ixazomib dosing in those who remained cGVHD free compared with those developed cGVHD. This study shows that the novel strategy of short-course oral ixazomib following allogeneic HCT is safe but did not demonstrate significant improvement in cGVHD incidence in recipients of MRD and MUD transplantation compared with matched CIBMTR controls. This study is registered at www.clinicaltrials.gov as NCT02250300.

Optimal Donor for African Americans with Hematologic Malignancy: HLA-Haploidentical Relative or Umbilical Cord Blood Transplant.

Although hematopoietic cell transplantation from an HLA-matched unrelated donor is potentially curative for hematologic malignancies, survival is lower for African Americans compared with Caucasians. Because only approximately 20% of African Americans will have an HLA-matched unrelated donor, many of these patients undergo HLA-haploidentical relative or umbilical cord blood transplantation. In this study, we analyzed outcomes after HLA-haploidentical related donor (n = 249) and umbilical cord blood (n = 118) transplantations in African American patients with hematologic malignancy between 2008 and 2016. The predominant disease was acute myelogenous leukemia for recipients of both types of donor grafts. The incidences of grade II-IV and III-IV acute graft-versus-host disease were higher after umbilical cord blood transplantation compared with HLA-haploidentical relative transplantation (56% and 29%, respectively, versus 33% and 11%, respectively; P < .0001). The 2-year incidence of transplantation-related mortality adjusted for age and conditioning regimen intensity was higher after umbilical cord blood transplantation compared with HLA-haploidentical related donor transplantation (31% versus 18%; P = .008); however, there were no between-group differences in the 2-year adjusted incidence of relapse (30% versus 34%; P = .51), overall survival (54% versus 57%; P = .66), or disease-free survival (43% versus 47%; P = .46). Our findings show that the use of HLA-haploidentical and umbilical cord blood transplants expands the access to transplantation with comparable leukemia-free and overall survival for African Americans with hematologic malignancies.