TRBC1-targeting antibody-drug conjugates for the treatment of T cell cancers.

Antibody and chimeric antigen receptor (CAR) T cell-mediated targeted therapies have improved survival in patients with solid and haematologic malignancies1-9. Adults with T cell leukaemias and lymphomas, collectively called T cell cancers, have short survival10,11 and lack such targeted therapies. Thus, T cell cancers particularly warrant the development of CAR T cells and antibodies to improve patient outcomes. Preclinical studies showed that targeting T cell receptor ß-chain constant region 1 (TRBC1) can kill cancerous T cells while preserving sufficient healthy T cells to maintain immunity12, making TRBC1 an attractive target to treat T cell cancers. However, the first-in-human clinical trial of anti-TRBC1 CAR T cells reported a low response rate and unexplained loss of anti-TRBC1 CAR T cells13,14. Here we demonstrate that CAR T cells are lost due to killing by the patient's normal T cells, reducing their efficacy. To circumvent this issue, we developed an antibody-drug conjugate that could kill TRBC1+ cancer cells in vitro and cure human T cell cancers in mouse models. The anti-TRBC1 antibody-drug conjugate may provide an optimal format for TRBC1 targeting and produce superior responses in patients with T cell cancers.

Alternative donor BMT with posttransplant cyclophosphamide as initial therapy for acquired severe aplastic anemia.

Severe aplastic anemia (SAA) is a marrow failure disorder with high morbidity and mortality. It is treated with bone marrow transplantation (BMT) for those with fully matched donors, or immunosuppressive therapy (IST) for those who lack such a donor, which is often the case for underrepresented minorities. We conducted a prospective phase 2 trial of reduced-intensity conditioning HLA-haploidentical BMT and posttransplantation cyclophosphamide (PTCy)-based graft-versus-host (GVHD) prophylaxis as initial therapy for patients with SAA. The median patient age was 25 years (range, 3-63 years), and the median follow-up time was 40.9 months (95% confidence interval [CI], 29.4-55.7). More than 35% of enrollment was from underrepresented racial/ethnic groups. The cumulative incidence of grade 2 or 4 acute GVHD on day 100 was 7% (95% CI, not applicable [NA]-17), and chronic GVHD at 2 years was 4% (95% CI, NA-11). The overall survival of 27 patients was 92% (95% CI, 83-100) at 1, 2, and 3 years. The first 7 patients received lower dose total body irradiation (200 vs 400 cGy), but these patients were more likely to have graft failure (3 of 7) compared with 0 of 20 patients in the higher dose group (P = .01; Fisher exact test). HLA-haploidentical BMT with PTCy using 400 cGy total body irradiation resulted in 100% overall survival with minimal GVHD in 20 consecutive patients. Not only does this approach avoid any adverse ramifications of IST and its low failure-free survival, but the use of haploidentical donors also expands access to BMT across all populations. This trial was registered at www.clinicaltrials.gov as NCT02833805.

NCCN Guidelines® Insights: Central Nervous System Cancers, Version 2.2022.

The NCCN Guidelines for Central Nervous System (CNS) Cancers focus on management of the following adult CNS cancers: glioma (WHO grade 1, WHO grade 2-3 oligodendroglioma [1p19q codeleted, IDH-mutant], WHO grade 2-4 IDH-mutant astrocytoma, WHO grade 4 glioblastoma), intracranial and spinal ependymomas, medulloblastoma, limited and extensive brain metastases, leptomeningeal metastases, non-AIDS-related primary CNS lymphomas, metastatic spine tumors, meningiomas, and primary spinal cord tumors. The information contained in the algorithms and principles of management sections in the NCCN Guidelines for CNS Cancers are designed to help clinicians navigate through the complex management of patients with CNS tumors. Several important principles guide surgical management and treatment with radiotherapy and systemic therapy for adults with brain tumors. The NCCN CNS Cancers Panel meets at least annually to review comments from reviewers within their institutions, examine relevant new data from publications and abstracts, and reevaluate and update their recommendations. These NCCN Guidelines Insights summarize the panel's most recent recommendations regarding molecular profiling of gliomas.

NCCN Guidelines® Insights: B-Cell Lymphomas, Version 6.2023.

Novel targeted therapies (small molecule inhibitors, antibody-drug conjugates, and CD19-directed therapies) have changed the treatment landscape of relapsed/refractory B-cell lymphomas. Bruton's tyrosine kinase (BTK) inhibitors continue to evolve in the management of mantle cell lymphoma (MCL), in both the relapsed/refractory and the frontline setting. Anti-CD19 CAR T-cell therapies are now effective and approved treatment options for relapsed/refractory follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), and MCL. Bispecific T-cell engagers represent a novel immunotherapeutic approach for relapsed FL and DLBCL after multiple lines of therapies, including prior CAR T-cell therapy. These NCCN Guideline Insights highlight the significant updates to the NCCN Guidelines for B-Cell Lymphomas for the treatment of FL, DLBCL, and MCL.

NCCN Guidelines® Insights: B-Cell Lymphomas, Version 5.2021.

In the last decade, a better understanding of the molecular pathogenesis of B-cell non-Hodgkin lymphomas has resulted in the development of novel targeted therapies, such as small molecule inhibitors of select kinases in the B-cell receptor pathway, antibody-drug conjugates, and small molecules that target a variety of proteins (eg, CD-19, EZH2, and XPO-1-mediated nuclear export). Anti-CD19 CAR T-cell therapy, first approved for relapsed/refractory (R/R) diffuse large B-cell lymphoma, has also emerged as a novel treatment option for R/R follicular lymphoma and mantle cell lymphoma. These NCCN Guideline Insights highlight the new targeted therapy options included in the NCCN Guidelines for B-Cell Lymphomas for the treatment of R/R disease.

Non-Myeloablative Allogeneic Transplantation with Post-Transplant Cyclophosphamide after Immune Checkpoint Inhibition for Classic Hodgkin Lymphoma: A Retrospective Cohort Study.

: Immune checkpoint inhibitors (ICIs) are approved in relapsed classic Hodgkin lymphoma (cHL). The safety and effectiveness of allogeneic blood or marrow transplantation (alloBMT) in ICI-pretreated patients with cHL remain unclear. The aim of this study is to assess outcomes of patients with cHL receiving ICIs before alloBMT using post-transplantation cyclophosphamide (PTCy) graft-versus-host-disease (GVHD) prophylaxis.  : We performed a retrospective study of relapsed/refractory patients with cHL undergoing alloBMT with PTCy at Johns Hopkins between November 2004 and September 2019. Engraftment, GVHD incidence, nonrelapse mortality, progression-free survival (PFS), and overall survival (OS) were compared between patients receiving pre-alloBMT ICI or standard salvage chemotherapy.  : We identified 105 consecutive relapsed/refractory patients with cHL, of whom 37 (35.2%) received ICIs and 68 (64.7%) received chemotherapy without ICIs (no-ICI) before alloBMT. ICI and no-ICI patients experienced a 3-year estimated OS of 94% versus 78% (hazard ratio [HR], 0.35; 95% confidence interval [CI], 0.08 to 1.56; P = .17) and a 3-year estimated PFS of 90% and 65% (HR, 0.3; 95% CI, 0.09 to 1; P = .05), respectively. We observed no statically significant difference in the 12-month cumulative incidence of acute grade II to IV GVHD or in the 24-month incidence of chronic GVHD.  : ICIs do not increase acute or chronic GVHD incidence compared with salvage chemotherapy. Patients with cHL receiving ICIs prior to alloBMT experienced outstanding PFS and OS. Thus, ICI therapy is safe in patients with cHL when undergoing alloBMT with PTCy and may improve post-alloBMT disease progression and survival.

Shortened-Duration Immunosuppressive Therapy after Nonmyeloablative, Related HLA-Haploidentical or Unrelated Peripheral Blood Grafts and Post-Transplantation Cyclophosphamide.

With post-transplantation cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis, nonmyeloablative (NMA) HLA-haploidentical (haplo) and HLA-matched blood or marrow transplantation (BMT) have comparable outcomes. Previous reports have shown that discontinuation of immunosuppression (IS) as early as day 60 after infusion of a bone marrow (BM) haplo allograft with PTCy is feasible. There are certain diseases in which peripheral blood (PB) may be favored over BM, but given the higher rates of GVHD with PB, excessive GVHD is of increased concern. We report a completed, prospective single-center trial of stopping IS at days 90 and 60 after NMA PB stem cell transplantation (PBSCT). Between 12/2015-7/2018, 117 consecutive patients with hematologic malignancies associated with higher rates of graft failure after NMA conditioned BMT and PTCy, received NMA PB allografts on trial. The primary objective of this study was to evaluate the safety and feasibility of reduced-duration IS (from day 5 through day 90 in the D90 cohort and through day 60 in the D60 cohort). Of the 117 patients (median age, 64 years; range, 22 to 78 years), the most common diagnoses were myelodysplastic syndrome (33%), acute myelogenous leukemia (with minimal residual disease or arising from an antecedent disorder) (32%), myeloproliferative neoplasms (19%), myeloma (9%), and chronic lymphoblastic leukemia (7%). Shortened IS was feasible in 75 patients (64%) overall. Ineligibility for shortened IS resulted most commonly from GVHD (17 patients), followed by early relapse (11 patients), nonrelapse mortality (NRM) (7 patients), patient/ physician preference (4 patients) or graft failure (3 patients). Of the 57 patients in the D90 cohort, 33 (58%) stopped IS early as planned, and among the 60 patients in the D60 cohort, 42 (70%) stopped IS early as planned. The graft failure rate was 2.6%. After IS cessation, the median time to diagnosis of grade II-IV acute GVHD was 21 days in the D90 cohort and 32 days in the D60 cohort, with almost all cases developing within 40 days. Approximately one-third of these patients resumed IS. All outcome measures were similar in the 2 cohorts and our historical outcomes with 180 days of IS. The cumulative incidence of grade III-IV acute GVHD was low, 2% in the D90 cohort and 7% in the D60 cohort. The incidence of severe chronic GVHD at 2 years was 9% in the D90 cohort and 5% in the D60 cohort. The 2-year overall survival was 67% for both the D90 and D60 cohorts. The 2-year progression-free survival was 47% for the D90 cohort and 52% for the D60 cohort, and the GVHD-free, relapse-free survival was <35% for both cohorts. These data suggest that reduced-duration IS in patients undergoing NMA PBSCT with PTCy is feasible and has an acceptable safety profile. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Thrombotic Microangiopathy after Post-Transplantation Cyclophosphamide-Based Graft-versus-Host Disease Prophylaxis.

Transplant-associated thrombotic microangiopathy (taTMA) is a systemic vascular illness associated with significant morbidity and mortality, resulting from a convergence of risk factors after allogeneic blood or marrow transplantation (alloBMT). The diagnosis of taTMA has been a challenge, but most criteria include an elevated lactate dehydrogenase (LDH), low haptoglobin, and schistocytes on peripheral blood smear. We performed a retrospective review of the 678 consecutive adults who received high-dose post-transplantation cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis between January 1, 2015, and August 31, 2018. In April 2016, we initiated a monitoring program of weekly LDH and haptoglobin measurements and blood smears when those 2 parameters were both abnormal on all of our adult patients undergoing alloBMT for hematologic malignancies. During the entire period, the 1-year cumulative incidence of taTMA was 1.4% (95% confidence interval, 0.5% to 2.3%). Eight patients were taking tacrolimus at the time of diagnosis, and 1 was not on any immunosuppression. Eight of 9 patients (89%) were hypertensive. Four patients had invasive infections at the time of diagnosis, 4 patients required renal replacement therapy, and 5 of 9 patients were neurologically impaired. Eculizumab was given to 6 patients (0.9%), of whom 2 died and 4 recovered with resolution of end-organ dysfunction. The paucity of events made the determination of risk factors difficult; however, the low incidence of taTMA in this cohort may be related to the limited use of myeloablative conditioning regimens, low incidence of severe GVHD, and use of PTCy. PTCy-based GVHD prophylaxis appears to be associated with a low incidence of severe taTMA.

Allogeneic Haploidentical Blood or Marrow Transplantation with Post-Transplantation Cyclophosphamide in Chronic Lymphocytic Leukemia.

Allogeneic blood or marrow transplantation (allo-BMT) remains the only treatment for chronic lymphocytic leukemia (CLL) with curative potential. Although post-transplantation cyclophosphamide (PTCy) reduces allo-BMT toxicity by decreasing the risk of graft-versus-host disease (GVHD), its effect on CLL allo-BMT outcomes is unknown. We studied 64 consecutive patients with CLL who underwent nonmyeloablative (NMA) haploidentical allo-BMT at Johns Hopkins Sidney Kimmel Comprehensive Cancer Center. In this cohort, the 4-year overall survival was 52% (95% confidence interval [CI], 40% to 68%), and progression-free survival was 37% (95% CI, 26% to 54%). Six patients experienced engraftment failure. PTCy prophylaxis was associated with a modest cumulative incidence of 1-year grade II-IV acute GVHD (27%; %95% CI, 15% to 38%) and %%%2-year chronic GVHD (17%; 95% CI, 7% to 26%). We demonstrate that NMA haploidentical allo-BMT with PTCy is a safe and effective treatment option.

Challenges in the Treatment of Newly Diagnosed and Recurrent Primary Central Nervous System Lymphoma.

Primary central nervous system lymphomas (PCNSLs) are rare cancers of the central nervous system (CNS) and are predominantly diffuse large B-cell lymphomas of the activated B-cell (ABC) subtype. They typically present in the sixth and seventh decade of life, with the highest incidence among patients aged >75 years. Although many different regimens have demonstrated efficacy in newly diagnosed and relapsed or refractory PCNSL, there have been few randomized prospective trials, and most recommendations and treatment decisions are based on single-arm phase II trials or even retrospective studies. High-dose methotrexate (HD-MTX; 3-8 g/m2) is the backbone of preferred standard induction regimens. Various effective regimens with different toxicity profiles can be considered that combine other chemotherapies and/or rituximab with HD-MTX, but there is currently no consensus for a single preferred regimen. There is controversy about the role of various consolidation therapies for patients who respond to HD-MTX-based induction therapy. For patients with relapsed or refractory PCNSL who previously experienced response to HD-MTX, repeat treatment with HD-MTX-based therapy can be considered depending on the timing of recurrence. Other more novel and less toxic regimens have been developed that show efficacy in recurrent disease, including ibrutinib, or lenalidomide ± rituximab. There is uniform agreement to delay or avoid whole-brain radiation therapy due to concerns for significant neurotoxicity if a reasonable systemic treatment option exists. This article aims to provide a clinically practical approach to PCNSL, including special considerations for older patients and those with impaired renal function. The benefits and risks of HD-MTX or high-dose chemotherapy with autologous stem cell transplantation versus other, better tolerated strategies are also discussed. In all settings, the preferred treatment is always enrollment in a clinical trial if one is available.

Central Nervous System Cancers, Version 3.2020, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Guidelines for Central Nervous System (CNS) Cancers focus on management of adult CNS cancers ranging from noninvasive and surgically curable pilocytic astrocytomas to metastatic brain disease. The involvement of an interdisciplinary team, including neurosurgeons, radiation therapists, oncologists, neurologists, and neuroradiologists, is a key factor in the appropriate management of CNS cancers. Integrated histopathologic and molecular characterization of brain tumors such as gliomas should be standard practice. This article describes NCCN Guidelines recommendations for WHO grade I, II, III, and IV gliomas. Treatment of brain metastases, the most common intracranial tumors in adults, is also described.

Development of Grade II Acute Graft-versus-Host Disease Is Associated with Improved Survival after Myeloablative HLA-Matched Bone Marrow Transplantation using Single-Agent Post-Transplant Cyclophosphamide.

Post-transplant cyclophosphamide (PTCy) can be used as the sole immunosuppression after myeloablative conditioning (MAC) for HLA-matched bone marrow transplantation (BMT). However, the effects of graft-versus-host disease (GVHD) with this platform are undefined. We retrospectively analyzed 298 consecutive adult patients with hematologic malignancies who engrafted after MAC HLA-matched sibling donor (MSD; n = 187) or HLA-matched unrelated donor (MUD; n = 111) T-cell-replete BMT with PTCy 50 mg/kg on days +3 and +4. After MSD and MUD BMT, 35% and 57% of patients, respectively, developed grade II acute GVHD (aGVHD) by 100 days, 11% and 14% grade III to IV aGVHD by 100 days, and 9% and 16% chronic GVHD (cGVHD) by 1 year. In landmark analyses at 100 days after HLA-matched BMT, 4-year overall survival (OS) and progression-free survival (PFS) were 57% (95% confidence interval [CI], .49 to .67) and 40% (95% CI, .31 to .51) in patients without grades II to IV aGVHD, and 68% (95% CI, .59 to .78) and 54% (95% CI, .44 to .65) in patients with grade II aGVHD. In adjusted time-dependent multivariable analyses, grade II aGVHD was associated with improved OS (hazard ratio, .58; 95% CI, .37 to .89; P = .01) and PFS (hazard ratio, .50; 95% CI, .34 to .74; P < .001) after HLA-matched BMT with PTCy. The ability of PTCy to limit grades III to IV aGVHD and cGVHD while maintaining grade II aGVHD may contribute to its effectiveness, and further attempts to reduce aGVHD may be detrimental.

Severe Cytokine Release Syndrome after Haploidentical Peripheral Blood Stem Cell Transplantation.

Inflammatory cytokines released by activated lymphocytes and innate cells in the context of cellular therapy can cause fever, vasodilatation, and end-organ damage, collectively known as cytokine release syndrome (CRS). CRS can occur after allogeneic blood or marrow transplantation, but is especially prevalent after HLA-haploidentical (haplo) peripheral blood transplantation (PBT). We reviewed charts of all patients who underwent haplo-PBT between October 1, 2013, and September 1, 2017 and graded CRS in these patients. A total of 146 consecutive patients who underwent related haplo-PBT were analyzed. CRS occurred in 130 patients (89%), with most cases of mild severity (grade 0 to 2). Severe CRS (grade 3 to 5) occurred in 25 patients (17%). In this group with severe CRS, 13 patients had encephalopathy, 12 required hemodialysis, and 11 were intubated. Death from the immediate complications of CRS occurred in 6 patients (24% of the severe CRS group and 4% of the entire haplo-PBT cohort). The cumulative probability of nonrelapse mortality (NRM) was 38% at 6 months for the patients with severe CRS and 8% (121 of 146) in patients without severe CRS. In conclusion, CRS occurs in nearly 90% of haplo-PBTs. Older haplo-PBT recipients (odds ratio [OR], 2.4; 95% confidence interval [CI], .83 to 6.75; P = .11) and those with a history of radiation therapy (OR, 3.85; 95% CI, 1.32 to 11.24; P = .01) are at increased risk of developing severe CRS. Although most recipients of haplo-PBT develop CRS, <20% experience severe complications. The development of severe CRS is associated with a significantly increased risk of NRM.

Low immunosuppressive burden after HLA-matched related or unrelated BMT using posttransplantation cyclophosphamide.

The intensive and prolonged immunosuppressive therapy required to prevent or treat graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT) puts patients at substantial risk for life-threatening infections, organ toxicity, and disease relapse. Posttransplantation cyclophosphamide (PTCy) can function as single-agent GVHD prophylaxis after myeloablative, HLA-matched related (MRD), or HLA-matched unrelated (MUD) donor T-cell-replete bone marrow allografting, obviating the need for additional prophylactic immunosuppression. However, patients who develop GVHD require supplemental treatment. We assessed the longitudinal requirement for immunosuppressive therapy in 339 patients treated with this transplantation platform: 247 receiving busulfan/cyclophosphamide (BuCy) conditioning (data collected retrospectively) and 92 receiving busulfan/fludarabine (BuFlu) conditioning (data collected prospectively). Approximately 50% of MRD patients and 30% of MUD patients never required immunosuppression beyond PTCy. In patients requiring further immunosuppression, typically only 1 to 2 agents were required, and the median durations of systemic pharmacologic immunosuppression for the BuCy MRD, BuFlu MRD, BuCy MUD, and BuFlu MUD groups all were 4.5 to 5 months. For these 4 groups, 1-year probabilities of being alive and off all systemic immunosuppression were 61%, 53%, 53%, and 51% and 3-year probabilities were 53%, 48%, 49%, and 56%, respectively. These data suggest that PTCy minimizes the global immunosuppressive burden experienced by patients undergoing HLA-matched alloBMT.

NCCN Guidelines Insights: B-Cell Lymphomas, Version 3.2019.

Diffuse large B-cell lymphomas (DLBCLs) and follicular lymphoma (FL) are the most common subtypes of B-cell non-Hodgkin's lymphomas in adults. Histologic transformation of FL to DLBCL (TFL) occurs in approximately 15% of patients and is generally associated with a poor clinical outcome. Phosphatidylinositol 3-kinase (PI3K) inhibitors have shown promising results in the treatment of relapsed/refractory FL. CAR T-cell therapy (axicabtagene ciloleucel and tisagenlecleucel) has emerged as a novel treatment option for relapsed/refractory DLBCL and TFL. These NCCN Guidelines Insights highlight important updates to the NCCN Guidelines for B-Cell Lymphomas regarding the treatment of TFL and relapsed/refractory FL and DLBCL.

Correction to: White matter changes in primary central nervous system lymphoma patients treated with high-dose methotrexate with or without rituximab.

The following discrepancies and errors were found in the original publication.

White matter changes in primary central nervous system lymphoma patients treated with high-dose methotrexate with or without rituximab.

PURPOSE: White matter changes (WMCs) can develop following systemic chemotherapy in patients with primary central nervous system lymphomas (PCNSLs), but the frequency and extent of these changes is not well characterized. This single center retrospective semi-quantitative study was performed to determine the rate, timing and grade of WMC on MRI in adult patients with newly-diagnosed radiotherapy-naïve PCNSL undergoing treatment with high-dose methotrexate (HD-MTX) with or without the addition of rituximab (-R). METHODS: Serial MRI scans of consecutive adult PCNSL patients treated with HD-MTX ± R were assessed for WMC comparing the pre-treatment to post-treatment scans utilizing a 0-to-8-point severity scoring system. RESULTS: Forty-seven PCNSL patients treated with either HD-MTX-R (n = 34; median age 66, 50% male) or HD-MTX (n = 13; median age 53, 54% male) were included in the analysis. WMC were detected in 62% (95% CI 46-76%) overall, in 68% of the HD-MTX-R, and in 46% of the HD-MTX group. Among patients with WMC (n = 29), WMC were first detected at an average of 2.8 months from beginning of therapy in the HD-MTX-R versus at 10.7 months in the HD-MTX group. Average WMC non-zero scores when first detected following the start of treatment were 2.5 (± 1.1) in HD-MTX-R and 1.5 (± 0.6) in HD-MTX. CONCLUSIONS: Development of WMC in PCNSL patients treated with MTX and MTX-R is common. WMC changes appear to be more frequent, occur earlier and are more extensive in patients treated with HD-MTX-R compared to HD-MTX. Prospective studies are required to determine whether WMC correlate with survival or neurocognitive outcomes.

Shortened-Duration Tacrolimus after Nonmyeloablative, HLA-Haploidentical Bone Marrow Transplantation.

With post-transplantation cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis, nonmyeloablative HLA-haploidentical (NMA haplo) and HLA-matched blood or marrow transplantation (BMT) have comparable outcomes. Early discontinuation of immunosuppression may reduce the risk of relapse and improve immune reconstitution, but may increase the risk of GVHD. We conducted a prospective trial of NMA haplo BMT for patients with hematologic malignancies (median age, 61 years), evaluating the safety of early discontinuation of tacrolimus. All patients received T cell-replete bone marrow followed by high-dose PTCy, mycophenolate mofetil, and tacrolimus. Tacrolimus was prespecified to stop without taper at day +90, +60, or +120, contingent on having ≥5% donor T cells, no relapse, and no grade II-IV acute or significant chronic GVHD. Safety stopping rules were based on ≥5% graft failure, ≥10% nonrelapse mortality (NRM), or a ≥20% combined incidence of severe acute and chronic GVHD from the tacrolimus stop date through day +180. Of the 47 patients in the day +90 arm, 23 (49%) stopped tacrolimus as planned. Of the 55 patients in the day +60 arm, 38 (69%) stopped as planned. Safety stopping criteria were not met. In both arms, at day +180, the probability of grade II-IV acute GVHD was <40%, that of grade III-IV acute GVHD was <8%, and that of NRM was <5%. The 1-year probabilities of chronic GVHD and NRM were <15% and <10%, respectively, in both arms. The 1-year GVHD-free relapse-free survival was higher in the day 60 arm. Thus, stopping tacrolimus as early as day +60 is feasible and carries acceptable risks after NMA haplo BMT with PTCy. This approach may facilitate post-transplantation strategies for relapse reduction.

Early Fever after Haploidentical Bone Marrow Transplantation Correlates with Class II HLA-Mismatching and Myeloablation but Not Outcomes.

Noninfectious fevers are common early after T cell-replete HLA haploidentical (haplo) peripheral blood transplants and have been associated with cytokine release syndrome and overall mortality. However, less is known regarding the incidence and associations of early fever after bone marrow transplantation (BMT) with post-transplant cyclophosphamide (PTCy). We hypothesized that early fever would be associated with myeloablative conditioning (MAC), because of its relative increase in tissue damage augmenting antigen presentation and class II HLA-mismatching because of recognition of antigen-presenting cells by CD4+ T cells. In 672 recipients of MAC HLA-matched related donor (MRD) (n = 183), MAC HLA-matched unrelated donor (MUD) (n = 115), MAC haplo (n = 79), or nonmyeloablative (NMA) haplo (n = 295) T cell-replete BMT with PTCy, we retrospectively analyzed early noninfectious fever defined as temperature of ≥38.3°C once or ≥38.0°C twice or more on days 1 to 6. Fever occurred in 13% after MAC MRD, 23% after MAC MUD, 44% after NMA haplo, and 84% after MAC haplo BMT (P < .0001). Survival outcomes did not differ between patients with and without early fever. In NMA haplo BMT, mismatch in the graft-versus-host direction at HLA-DRB1 or -DPB1 (but not HLA-A, -B, -Cw, or -DQB1) was associated with early fever compared with no mismatches at these loci (P < .0001 and P = .02, respectively). In multivariable modeling, -DRB1 or -DPB1 mismatch and higher CD3+ graft cell dose were significantly associated with early fever. Early fever is more common after haplo compared with HLA-matched BMT. Fever is associated with myeloablation, -DRB1 or -DPB1 mismatching, and higher CD3+ graft cell dose but not survival.

Haploidentical Bone Marrow Transplantation with Post-Transplant Cyclophosphamide Using Non-First-Degree Related Donors.

Outcomes of nonmyeloablative (NMA) haploidentical (haplo) blood or marrow transplant (BMT) with post-transplantation cyclophosphamide (PTCy) using non-first-degree relatives are unknown. We evaluated 33 consecutive adult patients (median age, 56 years) with hematologic malignancies who underwent NMA haplo T cell-replete BMT with PTCy at Johns Hopkins using second- or third-degree related donors. Donors consisted of 10 nieces (30%), 9 nephews (27%), 7 first cousins (21%), 5 grandchildren (15%), and 2 uncles (6%). Thirty-one patients (94%) reached full donor chimerism by day 60. The estimated cumulative incidence (CuI) of grades II to IV acute graft-versus-host disease (aGVHD) at day 180 was 24% (90% confidence interval [CI], 9% to 38%). Only 1 patient experienced grades III to IV aGVHD. At 1 year the CuI of chronic GVHD was 10% (90% CI, 0% to 21%). The CuI of nonrelapse mortality at 1 year was 5% (90% CI, 0% to 14%). At 1 year the probability of relapse was 31% (90% CI, 12% to 49%), progression-free survival 64% (90% CI, 48% to 86%), and overall survival 95% (90% CI, 87% to 100%). The 1-year probability of GVHD-free, relapse-free survival was 57% (90% CI, 41% to 79%). NMA haplo BMT with PTCy from non-first-degree relatives is an acceptably safe and effective alternative donor platform, with results similar to those seen with first-degree relatives.