JAK2/mTOR Inhibition Fails to Prevent Acute GVHD Despite Reduced Th1/Th17 cells: Final Phase II Trial Results.

Our phase I graft-versus-host disease (GVHD) prevention trial of JAK2 inhibitor, pacritinib, (recommended phase II dose: 100mg po BID day 0 to +70) plus sirolimus and tacrolimus (PAC/SIR/TAC) demonstrated the regimen was safe and free of pan-JAK myelosuppression after allogeneic hematopoietic cell transplantation (alloHCT). PAC inhibits IL-6 receptor activity and pathogenic Th1/Th17 differentiation in preclinical models and the phase I trial. Herein we report on our completed phase II trial of PAC/SIR/TAC after 8/8-HLA matched alloHCT. This single-arm phase II trial (NCT02891603) was powered to determine if PAC/SIR/TAC suppressed %pSTAT3+ CD4+ T cells at day +21 (primary endpoint: %pSTAT3+ CD4+ T cells ≤ 35%) and estimated grade II-IV acute GVHD by day +100. The impact of PAC/SIR/TAC on T cell subsets, CD28 (pS6 and pH3ser10), and IL-2 receptor (pSTAT5) signal transduction was also evaluated. Eligible patients (n=28) received alloHCT for hematologic malignancies or myeloproliferative neoplasms. Reduced or myeloablative intensity conditioning was permitted. PAC/SIR/TAC met the primary endpoint, reducing %pSTAT3+ CD4+ T cells to 9.62% at day +21. Th1/Th17 cells were decreased at day +21, increasing the ratio of Tregs to Th1 and Th17 cells with PAC/SIR/TAC at RP2D PAC compared to dose level 1 PAC. The cumulative incidence of grade II-IV acute GVHD by day +100 with PAC/SIR/TAC was similar to historic SIR/TAC values (46 v 43%). While PAC/SIR/TAC suppressed pSTAT3 and Th1/Th17 cells, the regimen did not improve acute GVHD prevention.

Tumor interferon signaling and suppressive myeloid cells are associated with CAR T-cell failure in large B-cell lymphoma.

Axicabtagene ciloleucel (axi-cel) is a chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory large B-cell lymphoma (LBCL). This study evaluated whether immune dysregulation, present before CAR T-cell therapy, was associated with treatment failure. Tumor expression of interferon (IFN) signaling, high blood levels of monocytic myeloid-derived suppressor cells (M-MDSCs), and high blood interleukin-6 and ferritin levels were each associated with a lack of durable response. Similar to other cancers, we found that in LBCL tumors, IFN signaling is associated with the expression of multiple checkpoint ligands, including programmed cell death-ligand 1, and these were higher in patients who lacked durable responses to CAR-T therapy. Moreover, tumor IFN signaling and blood M-MDSCs associated with decreased axi-cel expansion. Finally, patients with high tumor burden had higher immune dysregulation with increased serum inflammatory markers and tumor IFN signaling. These data support that immune dysregulation in LBCL promotes axi-cel resistance via multiple mechanistic programs: insufficient axi-cel expansion associated with both circulating M-MDSC and tumor IFN signaling, which also gives rise to expression of immune checkpoint ligands.

Dual JAK2/Aurora kinase A inhibition prevents human skin graft rejection by allo-inactivation and ILC2-mediated tissue repair.

Prevention of allograft rejection often requires lifelong immune suppression, risking broad impairment of host immunity. Nonselective inhibition of host T cell function increases recipient risk of opportunistic infections and secondary malignancies. Here we demonstrate that AJI-100, a dual inhibitor of JAK2 and Aurora kinase A, ameliorates skin graft rejection by human T cells and provides durable allo-inactivation. AJI-100 significantly reduces the frequency of skin-homing CLA+ donor T cells, limiting allograft invasion and tissue destruction by T effectors. AJI-100 also suppresses pathogenic Th1 and Th17 cells in the spleen yet spares beneficial regulatory T cells. We show dual JAK2/Aurora kinase A blockade enhances human type 2 innate lymphoid cell (ILC2) responses, which are capable of tissue repair. ILC2 differentiation mediated by GATA3 requires STAT5 phosphorylation (pSTAT5) but is opposed by STAT3. Further, we demonstrate that Aurora kinase A activation correlates with low pSTAT5 in ILC2s. Importantly, AJI-100 maintains pSTAT5 levels in ILC2s by blocking Aurora kinase A and reduces interference by STAT3. Therefore, combined JAK2/Aurora kinase A inhibition is an innovative strategy to merge immune suppression with tissue repair after transplantation.

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.

Targeting JAK2 reduces GVHD and xenograft rejection through regulation of T cell differentiation.

Janus kinase 2 (JAK2) signal transduction is a critical mediator of the immune response. JAK2 is implicated in the onset of graft-versus-host disease (GVHD), which is a significant cause of transplant-related mortality after allogeneic hematopoietic cell transplantation (allo-HCT). Transfer of JAK2-/- donor T cells to allogeneic recipients leads to attenuated GVHD yet maintains graft-versus-leukemia. Th1 differentiation among JAK2-/- T cells is significantly decreased compared with wild-type controls. Conversely, iTreg and Th2 polarization is significantly increased among JAK2-/- T cells. Pacritinib is a multikinase inhibitor with potent activity against JAK2. Pacritinib significantly reduces GVHD and xenogeneic skin graft rejection in distinct rodent models and maintains donor antitumor immunity. Moreover, pacritinib spares iTregs and polarizes Th2 responses as observed among JAK2-/- T cells. Collectively, these data clearly identify JAK2 as a therapeutic target to control donor alloreactivity and promote iTreg responses after allo-HCT or solid organ transplantation. As such, a phase I/II acute GVHD prevention trial combining pacritinib with standard immune suppression after allo-HCT is actively being investigated (https://clinicaltrials.gov/ct2/show/NCT02891603).

Sole Upfront Therapy with Beclomethasone and Budesonide for Upper Gastrointestinal Acute Graft-versus-Host Disease.

Systemic glucocorticoids remain the standard treatment for gastrointestinal (GI) acute graft-versus-host disease (aGVHD) despite their toxicity and incomplete efficacy. Controlled trials have tested poorly absorbable steroids as adjuncts with systemic glucocorticoids, but only small case series have reported treatment with poorly absorbed beclomethasone dipropionate (BDP) and budesonide (BUD) alone. Our team has adopted the practice of administering BDP or BDP+BUD without systemic glucocorticoids as first-line therapy for isolated upper GI (UGI) aGVHD. We report results in 76 patients treated with BDP alone and in 81 patients treated with BDP+BUD, with allocation by physician choice. Almost all patients received peripheral blood stem cells (92%) from a fully HLA-matched related or unrelated donor (80%) after myeloablative conditioning (76%) for acute leukemia (49%), myelodysplastic syndrome (17%), non-Hodgkin lymphoma (14%), or another hematopoietic disorders (20%). After 28 days of treatment with BDP, 46% of the patients had a complete response (CR) and 10% had a partial response (PR); after 200 days, 61 (80%) patients were alive, 34% maintained a CR, and 3% maintained a PR, whereas 53% required additional immunosuppression (IS). After 28 days of treatment with BDP+BUD, 67% had a CR and 10% a PR; after 200 days, 74 (91%) patients were alive, 46% maintained a CR, and 2% maintained a PR, whereas 43% required additional IS. Among the entire cohort of 157 patients, 66 (42%) were treated successfully without systemic glucocorticoids. This study reports the efficacy of poorly absorbable steroids alone for patients with isolated UGI aGVHD. Prospective trials should test for the potential advantages of BDP and BUD use over systemic glucocorticoids.

Defining Competency to Empower Blood and Marrow Transplant and Cellular Immunotherapy Quality Management Professionals in Healthcare.

Blood and marrow transplant (BMT) programs worldwide frequently employ a quality management professional who is charged with securing quality and maintaining regulatory requirements. Although many BMT programs employ an individual to oversee quality management, there are no standard definitions of the education, training, and core competencies needed to successfully perform this role. The goal of this article is to propose the required qualifications and responsibilities of the BMT professional who oversees quality management and to elicit discussion to standardize such a role in BMT and cellular immunotherapy programs. Our results could serve as a model for quality managers in other complex healthcare environments. The recommendation and findings are primarily limited to cell therapy centers in North America.

Harmonization of Busulfan Plasma Exposure Unit (BPEU): A Community-Initiated Consensus Statement.

Busulfan therapeutic drug monitoring (TDM) is often used to achieve target plasma exposures. Variability in busulfan plasma exposure units (BPEU) is a potential source for misinterpretation of publications and protocols and is a barrier to data capture by hematopoietic cell transplantation (HCT) registry databases. We sought to harmonize to a single BPEU for international use. Using Delphi consensus methodology, iterative surveys were sent to an increasing number of relevant clinical stakeholders. In survey 1, 14 stakeholders were asked to identify ideal properties of a BPEU. In survey 2, 52 stakeholders were asked (1) to evaluate BPEU candidates according to ideal BPEU properties established by survey 1 and local position statements for TDM and (2) to identify potential facilitators and barriers to adoption of the harmonized BPEU. The most frequently used BPEU identified, in descending order, were area under the curve (AUC) in µM × min, AUC in mg × h/L, concentration at steady state (Css) in ng/mL, AUC in µM × h, and AUC in µg × h/L. All respondents conceptually agreed on the ideal properties of a BPEU and to adopt a harmonized BPEU. Respondents were equally divided between selecting AUC in µM × min versus mg × h/L for harmonization. AUC in mg × h/L was finally selected as the harmonized BPEU, because it satisfied most of the survey-determined ideal properties for the harmonized BPEU and is read easily understood in the clinical practice environment. Furthermore, 10 major professional societies have endorsed AUC in mg × h/L as the harmonized unit for reporting to HCT registry databases and for use in future protocols and publications.

Allogeneic hematopoietic stem cell transplantation for MDS and CMML: recommendations from an international expert panel.

An international expert panel, active within the European Society for Blood and Marrow Transplantation, European LeukemiaNet, Blood and Marrow Transplant Clinical Trial Group, and the International Myelodysplastic Syndromes Foundation developed recommendations for allogeneic hematopoietic stem cell transplantation (HSCT) in myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). Disease risks scored according to the revised International Prognostic Scoring System (IPSS-R) and presence of comorbidity graded according to the HCT Comorbidity Index (HCT-CI) were recognized as relevant clinical variables for HSCT eligibility. Fit patients with higher-risk IPSS-R and those with lower-risk IPSS-R with poor-risk genetic features, profound cytopenias, and high transfusion burden are candidates for HSCT. Patients with a very high MDS transplantation risk score, based on combination of advanced age, high HCT-CI, very poor-risk cytogenetic and molecular features, and high IPSS-R score have a low chance of cure with standard HSCT and consideration should be given to treating these patients in investigational studies. Cytoreductive therapy prior to HSCT is advised for patients with ≥10% bone marrow myeloblasts. Evidence from prospective randomized clinical trials does not provide support for specific recommendations on the optimal high intensity conditioning regimen. For patients with contraindications to high-intensity preparative regimens, reduced intensity conditioning should be considered. Optimal timing of HSCT requires careful evaluation of the available effective nontransplant strategies. Prophylactic donor lymphocyte infusion (DLI) strategies are recommended in patients at high risk of relapse after HSCT. Immune modulation by DLI strategies or second HSCT is advised if relapse occurs beyond 6 months after HSCT.

Hypoalbuminemia at Day +90 Is Associated with Inferior Nonrelapse Mortality and Overall Survival in Allogeneic Hematopoietic Cell Transplantation Recipients: A Confirmatory Study.

Prognostic biomarkers in allogeneic hematopoietic cell transplantation (allo-HCT) are needed to improve risk assessment and help guide therapeutic and surveillance strategies to mitigate the risk of death from the procedure. We previously identified hypoalbuminemia at day +90 post-transplantation as an independent predictor of increased nonrelapse mortality (NRM) and inferior overall survival (OS) in patients with acute myelogenous leukemia and myelodysplastic syndrome who were treated with an allo-HCT. Here, we aim to confirm the prognostic significance of day +90 hypoalbuminemia in 783 patients, median age 52 years (range, 18 to 76), who received an allo-HCT for various hematologic malignancies and bone marrow failure syndromes. Multivariate analysis for NRM demonstrated a negative effect of low serum albumin levels (<3.0 versus 3.0 to 3.5 versus >3.5 g/dL) at day +90 post-transplantation (hazard ratios, 8.03 [95% CI, 3.59 to 17.97] versus 2.84 [95% CI, 1.59 to 5.08] versus reference; P < .0001). This was also the case for OS (hazard ratios, 6.86 [95% CI, 4.24 to 11.10] versus 1.52 [95% CI, 1.05 to 2.20] versus reference; P < .0001). Patients with hypoalbuminemia at day +90 post-transplantation are more likely to die from causes other than relapse, particularly infections. This large study confirms the ability of day +90 serum hypoalbuminemia to predict worse NRM and inferior OS. Presence of hypoalbuminemia at day +90 should drive a more rigorous real-time surveillance strategy considering the anticipated high-risk of NRM and poor survival in these patients. Future studies should consider incorporating day +90 serum albumin levels in prognostic models of NRM and OS.

Intravenous Busulfan Compared with Total Body Irradiation Pretransplant Conditioning for Adults with Acute Lymphoblastic Leukemia.

Total body irradiation (TBI) has been included in standard conditioning for acute lymphoblastic leukemia (ALL) before hematopoietic cell transplantation (HCT). Non-TBI regimens have incorporated busulfan (Bu) to decrease toxicity. This retrospective study analyzed TBI and Bu on outcomes of ALL patients 18-60 years old, in first or second complete remission (CR), undergoing HLA-compatible sibling, related, or unrelated donor HCT, who reported to the Center for International Blood and Marrow Transplant Research from 2005 to 2014. TBI plus etoposide (25%) or cyclophosphamide (75%) was used in 819 patients, and intravenous Bu plus fludarabine (41%), clofarabine (30%), cyclophosphamide (15%), or melphalan (13%) was used in 299 patients. Bu-containing regimens were analyzed together, since no significant differences for patient outcomes were noted between them. Bu patients were older, with better performance status; took longer to achieve first CR and receive HCT; were treated more recently; and were more likely to receive peripheral blood grafts, antithymocyte globulin, or tyrosine kinase inhibitors. With median follow-up of 3.6 years for Bu and 5.3 years for TBI, adjusted 3-year outcomes showed treatment-related mortality Bu 19% versus TBI 25% (P = .04); relapse Bu 37% versus TBI 28% (P = .007); disease-free survival (DFS) Bu 45% versus TBI 48% (P = .35); and overall survival (OS) Bu 57% versus TBI 53% (P = .35). In multivariate analysis, Bu patients had higher risk of relapse (relative risk, 1.46; 95% confidence interval, 1.15 to 1.85; P = .002) compared with TBI patients. Despite the higher relapse, Bu-containing conditioning led to similar OS and DFS following HCT for ALL.

Recipient single nucleotide polymorphisms in Paneth cell antimicrobial peptide genes and acute graft-versus-host disease: analysis of BMT CTN-0201 and -0901 samples.

Host genetics shape the gut microbiota, and gut dysbiosis increases the risk of acute graft-versus-host disease (aGVHD). Paneth cells and microbiota have interactions that contribute to immune regulation. α-defensin-5 (HD5) and regenerating islet-derived protein 3 alpha (Reg3A) are the most abundant Paneth cell antimicrobial peptides (AMPs). We hypothesized that single nucleotide polymorphisms (SNPs) in the genes for HD5 (DEFA5) and Reg3A (REG3A) predict aGVHD risk. We analysed pre-transplant recipient peripheral blood mononuclear cell samples from randomized Blood and Marrow Transplant Clinical Trials Network (BMT CTN) studies 0201 (94 patients with bone marrow and 93 with peripheral blood grafts) and 0901 (86 patients with myeloablative and 77 with reduced-intensity conditioning; all using peripheral blood grafts). In multivariable analysis (with a SNP × graft source interaction term in CTN-0201 and a SNP × conditioning intensity term in CTN-0901), DEFA5 rs4415345 and rs4610776 were associated with altered incidence of aGVHD grade II-IV [rs4415345 G vs. C: hazard ratio (HR) 0·58, 95% confidence interval (95% CI) 0·37-0·92, P = 0·02; rs4610776 T vs. A: HR 1·53, 95% CI 1·01-2·32, P = 0·05] in CTN-0201, but not CTN-0901, suggesting a stronger effect in bone marrow allografts. REG3A SNP was not associated with aGVHD. Host genetics may influence aGVHD risk by modulating Paneth cell function.

Hypoalbuminaemia segregates different prognostic subgroups within the refined standard risk acute graft-versus-host disease score.

Hypoalbuminaemia has been previously described to predict worse non-relapse mortality (NRM) and inferior overall survival (OS) in allogeneic haematopoietic cell transplant (allo-HCT) recipients. Here, we evaluate the role of hypoalbuminaemia (<35 g/l) at time of onset of acute graft-versus-host disease (aGVHD) when incorporated into the refined aGVHD score. The study population consisted of 522 patients, median age 53 (18-75) years, who underwent an allo-HCT mostly for haematological malignancies. Standard risk (SR) aGVHD comprised 467 patients (89%) and the number of high risk (HR) cases was 55 (11%). Median follow-up for all surviving patients was 26 (3-55) months. Two-year OS was significantly better in patients with SR aGVHD with a serum albumin ≥35 g/l compared to SR with albumin <35 g/l [70% (95% CI = 64-76%) vs. 49% (95% CI = 42-56%), P < 0·0001]. Also, patients with SR aGVHD and a serum albumin level of ≥35 g/l had a significantly lower NRM at 1-year post-transplantation [6% (95% CI = 3-10%) vs. 25% (95% CI = 20-32%), P < 0·0001]. After our findings are validated in a large cohort of patients, we propose that hypoalbuminaemia should be incorporated into the refined aGVHD risk score to further its ability to predict outcomes within this group.

The effect of donor characteristics on survival after unrelated donor transplantation for hematologic malignancy.

There are >24 million registered adult donors, and the numbers of unrelated donor transplantations are increasing. The optimal strategy for prioritizing among comparably HLA-matched potential donors has not been established. Therefore, the objective of the current analyses was to study the association between donor characteristics (age, sex, parity, cytomegalovirus serostatus, HLA match, and blood group ABO match) and survival after transplantation for hematologic malignancy. The association of donor characteristics with transplantation outcomes was examined using either logistic or Cox regression models, adjusting for patient disease and transplantation characteristics associated with outcomes in 2 independent datasets: 1988 to 2006 (N = 6349; training cohort) and 2007 to 2011 (N = 4690; validation cohort). All donor-recipient pairs had allele-level HLA typing at HLA-A, -B, -C, and -DRB1, which is the current standard for selecting donors. Adjusting for patient disease and transplantation characteristics, survival was better after transplantation of grafts from young donors (aged 18-32 years) who were HLA matched to recipients (P < .001). These findings were validated for transplantations that occurred between 2007 and 2011. For every 10-year increment in donor age, there is a 5.5% increase in the hazard ratio for overall mortality. Increasing HLA disparity was also associated with worsening survival. Donor age and donor-recipient HLA match are important when selecting adult unrelated donors. Other donor characteristics such as sex, parity, and cytomegalovirus serostatus were not associated with survival. The effect of ABO matching on survival is modest and must be studied further before definitive recommendations can be offered.

In vivo IL-12/IL-23p40 neutralization blocks Th1/Th17 response after allogeneic hematopoietic cell transplantation.

T-helper 1 and T-helper 17 lymphocytes mediate acute graft-versus-host disease (GvHD). Interleukin 12 is critical for T-helper 1 differentiation and interleukin 23 for T-helper 17 maintenance. Interleukin 12 and 23 are heterodimeric cytokines that share the p40 subunit (IL-12/IL-23p40). In a randomized, blinded, placebo-controlled trial, we examined the biological impact and clinical outcomes following IL-12/IL-23p40 neutralization using ustekinumab. Thirty patients received peripheral blood mobilized hematopoietic cell transplantation (HCT) from HLA-matched sibling or unrelated donors, received sirolimus plus tacrolimus as GvHD prophylaxis, and were randomized to ustekinumab versus placebo with 1:1 allocation after stratification by donor type. The primary end point of the trial was the mean percentage (%) T-regulatory (Treg) cells on day 30 post HCT. Ustekinumab was delivered by subcutaneous injection on day -1 and day +20 after transplantation. On day 30 post transplant, no significant difference in % Treg was observed. Ustekinumab suppressed serum IL-12/IL-23p40 levels. Host-reactive donor alloresponse at days 30 and 90 after transplantation was polarized with significant reduction in IL-17 and IFN-α production and increase in IL-4. No toxicity attributed to ustekinumab was observed. Overall survival and National Institute of Health moderate/severe chronic GvHD-free, relapse-free survival were significantly improved among ustekinumab-treated patients. No significant improvements were observed in acute or chronic GvHD, relapse, or non-relapse mortality. These data provide first evidence that IL-12/IL-23p40 neutralization can polarize donor anti-host alloresponse in vivo and provide initial clinical efficacy evidence to be tested in subsequent trials. (Trial registered at clinicaltrials.gov identifier: 01713400).

T-bet Promotes Acute Graft-versus-Host Disease by Regulating Recipient Hematopoietic Cells in Mice.

Beyond its critical role in T cells, T-bet regulates the functions of APCs including dendritic cells and B cells, as well as NK cells. Given that recipient APCs are essential for priming allogeneic T cells and recipient NK or T cells are able to reject allogeneic donor cells, we evaluated the role of T-bet on the host in acute graft-versus-host disease (GVHD) using murine models of allogeneic bone marrow transplantation. T-bet(-/-) recipients developed significantly milder GVHD than their wild type counterparts in MHC-mismatched or CD4-dependent minor histocompatibility Ag-mismatched models. Allogeneic donor T cells, in particular, CD4 subset, significantly reduced IFN-γ production, proliferation and migration, and caused less injury in liver and gut of T-bet(-/-) recipients. We further observed that T-bet on recipient hematopoietic cells was primarily responsible for the donor T cell response and pathogenicity in GVHD. T-bet(-/-) dendritic cells expressed higher levels of Trail, whereas they produced lower levels of IFN-γ and IL-12/23 p40, as well as chemokine CXCL9, resulting in significantly higher levels of apoptosis, less priming, and infiltration of donor T cells. Meanwhile, NK cells in T-bet(-/-) hosts partially contribute to the decreased donor T cell proliferation. Furthermore, although T-bet on hematopoietic cells was required for GVHD development, it was largely dispensable for the graft-versus-leukemia effect. Taken together with our previous findings, we propose that T-bet is a potential therapeutic target for the control of GVHD through regulating donor T cells and recipient hematopoietic cells.

Identification of DPB1 Permissive Unrelated Donors Is Highly Likely.

HLA-DPB1 permissive matching based on T cell epitope (TCE) groups should be considered when selecting among equally matched HLA-A, -B, -C, -DRB1 unrelated hematopoietic stem cell donors to improve patient survival. Previous studies have defined 3 TCE groups based on functional assays of alloreactivity. Combinations of donor and recipient DPB1 alleles with low immunogenic potential identify permissive donors, who provide no increased risk of mortality compared with DPB1-matched donors. To determine the likelihood of identifying a DPB1 permissive-matched (includes both allele-matched and DPB1-permissive mismatched) unrelated donor for patients with high-resolution matches at 10/10 HLA-A, -B,- C, -DRB1, and -DQB1 in the Be The Match Registry, preliminary search requests from United States' transplant centers for 595 DPB1-typed patients were evaluated for existence of a DPB1 permissive-matched donor, identified either among already typed donors or by prospective DPB1 typing. The baseline DPB1 permissive match rate was 69% and improved to 80% after additional donor DPB1 typing (median, 4 donors per patient). When seeking a 10/10-matched, young (18- to 32-year-old) donor in the registry, the probability of finding a DPB1 permissive-matched donor started lower at 59% and improved to 70% after additional DPB1 testing. Our results show that most patients with a 10/10 match can find a DPB1 permissive-matched donor.

The Role of Age in Neurocognitive Functioning among Adult Allogeneic Hematopoietic Cell Transplant Recipients.

Improvements in supportive care have enabled allogeneic hematopoietic cell transplantation (HCT) to be performed in increasingly older patients. HCT is associated with neurocognitive impairment, which may be exacerbated in older adults due to normal neurocognitive decline associated with aging. The goal of this study was to evaluate whether increasing age of allogeneic HCT recipients is associated with worse neurocognitive outcomes over time relative to a matched sample of individuals without cancer. Patients (n = 140; 42% female; M age, 51 years; range, 20 to 76 years; 31% with acute myelogenous leukemia) completed neurocognitive assessments before transplantation and 3 months and 1 year after transplantation. Controls (n = 75; 56% female; M age, 53 years; range, 21 to 74 years) completed assessments at comparable time intervals. Linear mixed models revealed that regardless of age, patients demonstrated worse performance than controls before transplantation in verbal memory, visual memory, and total neuropsychological performance, and over time in executive functioning. In addition, older age was associated with worse performance in verbal memory (P = .02) and verbal fluency (P = .05) over time in patients compared with controls. Specifically, older (65+ years) patients had worse verbal memory and verbal fluency than older and younger (<65 years) controls post-transplantation (Cohen's d = .22 to .39). These data indicate that age may be a risk factor for worse neurocognitive outcomes after allogeneic HCT. If replicated, our results suggest that older candidates for allogeneic HCT should be counseled regarding the risk of cognitive problems after transplantation.