The immune response to Covid-19 mRNA vaccination among Lymphoma patients receiving anti-CD20 treatment.

The monoclonal antibody rituximab improves clinical outcome in the treatment of CD20-positive lymphomatous neoplasms, and it is an established drug for treatment of these cancers. Successful mRNA COVID-19 (SARS-CoV-2) vaccination is extremely important for lymphoma patients because they tend to be elderly with comorbidities which leaves them at increased risk of poor outcomes once infected by Coronavirus. Anti-CD20 therapies such as rituximab, deplete B-cell populations and can affect vaccine efficacy. Therefore, a knowledge of the effect of COVID-19 vaccination in this group is critical. We followed a cohort of 28 patients with CD20-positive lymphomatous malignancies treated with rituximab that started prior to their course of COVID-19 vaccination, including boosters. We assayed for vaccine "take" in the humoral (IgG and IgA) and cellular compartment. Here, we show that short-term and long-term development of IgG and IgA antibodies directed toward COVID-19 spike protein are reduced in these patients compared to healthy controls. Conversely, the robustness and breath of underlying T-cell response is equal to healthy controls. This response is not limited to specific parts of the spike protein but spans the spike region, including response to the conserved Receptor Binding Domain (RBD). Our data informs on rational vaccine design and bodes well for future vaccination strategies that require strong induction of T-cell responses in these patients.

Less is more: An analysis of venetoclax and hypomethylating agent post-induction treatment modifications in AML.

Venetoclax (Ven) combined with a hypomethylating agent (HMA) enhances survival in elderly/unfit acute myeloid leukemia (AML) patients, yet often necessitates regimen modifications due to intolerance. However, it is unclear how these modifications affect patient outcome. This retrospective cohort study evaluates the impact of post-induction HMA/Ven regimen modifications on disease progression and survival. This study reviewed 142 AML patients treated with HMA/Ven within the Northwell Health System from January 2019 to December 2022. To assess the impact of post-induction regimen modifications, patients were grouped according to median days between cycles (≤34 or ≥35 days cycle intervals) and median Ven days per cycle (≤14 or ≥15 days/cycle) based on only cycle 3 and beyond. Kaplan-Meier and Cox proportional hazard regression analyses were employed for univariate and multivariate assessments, respectively. There was no significant difference in median progression-free survival (mPFS)(11.6 vs 11.8 months, p = 0.73) or median overall survival (mOS)(15.1 vs 21.8 months, p = 0.16) between cycle interval groups. However, there was a clinically and statistically significant advantage in mPFS (15.8 vs 8.7 months, p = 0.01) and mOS (24.7 vs 11.3 months, p = 0.006) for patients with a median of ≤14 Ven days/cycle compared to ≥15 Ven days/cycle. Multivariate analysis demonstrated that ≤14 days of Ven for cycle 3 and beyond was an independent predictor of decreased mortality (HR 0.18, CI 0.07-0.48, p = 0.0007). Extended cycle intervals did not adversely affect mortality while reduced Ven duration per cycle post-induction was associated with improved survival in elderly AML patients.

Immune-related encephalitis after immune checkpoint inhibitor therapy.

BACKGROUND: Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment but can trigger immune-related encephalitis. We report one of the largest case series of patients with immune-related encephalitis and review of the literature. METHODS: Retrospective series of patients with immune-related encephalitis and literature review. RESULTS: Fourteen patients with cancer treated with ICI (50% combination therapy) developed immune-related encephalitis. Diagnostic testing revealed cerebral spinal fluid (CSF) lymphocytic pleocytosis (85%) and elevated protein (69%), abnormal brain magnetic resonance imaging(MRI) (33%) or brain FDG-PET (25%), electroencephalogram (EEG) abnormalities (30%), and autoantibodies (31%). Encephalitis treatment included: corticosteroids (86%), intravenous immunoglobulin (IVIg) (36%), plasmapheresis (7%), and rituximab (29%). There were no deaths and 12 patients had significant recovery, although long-term complications were observed. All patients discontinued ICI. Longitudinal follow-up demonstrated anti-cancer response to ICI at 3 months (85%) and 6 months post-ICI initiation (77%). A literature review identified 132 patients with immune-related encephalitis. Most were treated with PD-1 inhibitors (18% combination). Common abnormalities included elevated CSF protein (84%) or pleocytosis (77%), abnormal brain MRI (65%), or autoantibodies (47%). Nearly all were treated with corticosteroids, many required additional therapy with IVIg (26%) or rituximab (12%). Most patients had clinical improvement (81%) but a minority (10%) had a clinical relapse after completing corticosteroid taper. ICIs were resumed in 7 patients (5%), with relapse in 3. CONCLUSIONS AND RELEVANCE: Immune-related encephalitis is treatable and improves with corticosteroids in most cases but may require additional immunosuppression. Re-emergence of encephalitis is rare and does not typically result in adverse outcomes, and this should be considered in neurological immune-related adverse event management guidelines.

Kidney and urinary tract involvement in systemic mastocytosis.

Systemic mastocytosis (SM) is a disorder of excessive mast cell accumulation in tissues due to a somatic gain-of-function mutation, commonly in the KIT gene, which prevents apoptosis of mast cells. Whereas bone marrow, skin, lymph nodes, spleen and gastrointestinal tract are commonly involved, kidneys are rarely involved directly by SM. However, there are increasing reports of indirect kidney involvement in patients with SM. Novel anti-neoplastic agents to treat advanced forms of SM include non-specific tyrosine kinase inhibitors, which are reported to be associated with kidney dysfunction in some patients. SM is also associated with immune-mediated glomerulonephritis (GN) such as mesangioproliferative GN, membranous nephropathy and diffuse proliferative GN. Kidney injury, in the form of monoclonal deposition disease and primary light chain amyloidosis, is reported in SM associated with plasma cell dyscrasia. In this narrative review we discuss the various ways kidneys (and the urinary tract) are involved in patients with SM.

Allogeneic Blood or Marrow Transplantation with High-Dose Post-Transplantation Cyclophosphamide for Acute Lymphoblastic Leukemia in Patients Age ≥55 Years.

Patients age ≥55 years with acute lymphoblastic leukemia (ALL) fare poorly with conventional chemotherapy, with a 5-year overall survival (OS) of ∼20%. Tyrosine kinase inhibitors and novel B cell-targeted therapies can improve outcomes, but rates of relapse and death in remission remain high. Allogeneic blood or marrow transplantation (alloBMT) provides an alternative consolidation strategy, and post-transplantation cyclophosphamide (PTCy) facilitates HLA-mismatched transplantations with low rates of nonrelapse mortality (NRM) and graft-versus-host disease (GVHD). The transplantation database at Johns Hopkins was queried for patients age ≥55 years who underwent alloBMT for ALL using PTCy. The database included 77 such patients. Most received reduced-intensity conditioning (RIC) (88.3%), were in first complete remission (CR1) (85.7%), and had B-lineage disease (90.9%). For the entire cohort, 5-year relapse-free survival (RFS) and overall survival (OS) were 46% (95% confidence interval [CI], 34% to 57%) and 49% (95% CI, 37% to 60%), respectively. Grade III-IV acute GVHD occurred in only 3% of patients, and chronic GVHD occurred in 13%. In multivariable analysis, myeloablative conditioning led to worse RFS (hazard ratio [HR], 4.65; P = .001), whereas transplantation in CR1 (HR, .30; P = .004) and transplantation for Philadelphia chromosome-positive (Ph+) ALL versus T-ALL (HR, .29; P = .03) were associated with improved RFS. Of the 54 patients who underwent RIC alloBMT in CR1 for B-ALL, the 5-year RFS and OS were 62% (95% CI, 47% to 74%) and 65% (95% CI, 51% to 77%), respectively, with a 5-year relapse incidence of 16% (95% CI, 7% to 27%) and an NRM of 24% (95% CI, 13% to 36%). RIC alloBMT with PTCy in CR1 represents a promising consolidation strategy for B-ALL patients age ≥55 years.

Consensus opinion from an international group of experts on measurable residual disease in hairy cell leukemia.

A significant body of literature has been generated related to the detection of measurable residual disease (MRD) at the time of achieving complete remission (CR) in patients with hairy cell leukemia (HCL). However, due to the indolent nature of the disease as well as reports suggesting long-term survival in patients treated with a single course of a nucleoside analog albeit without evidence of cure, the merits of detection of MRD and attempts to eradicate it have been debated. Studies utilizing novel strategies in the relapse setting have demonstrated the utility of achieving CR with undetectable MRD (uMRD) in prolonging the duration of remission. Several assays including immunohistochemical analysis of bone marrow specimens, multi-parameter flow cytometry and molecular assays to detect the mutant BRAF V600E gene or the consensus primer for the immunoglobulin heavy chain gene (IGH) rearrangement have been utilized with few comparative studies. Here we provide a consensus report on the available data, the potential merits of MRD assessment in the front-line and relapse settings and recommendations on future role of MRD assessment in HCL.

CD34+ cell of origin for immunoglobulin heavy chain variable region unmutated, but not mutated, chronic lymphocytic leukemia.

The clinical course of chronic lymphocytic leukemia (CLL) is highly variable. Immunoglobulin heavy chain variable region (IgHV) mutation status is among the most important prognostic factors, with unmutated IgHV associated with inferior outcomes. CLL presumably arises from mature B cells. However, we hypothesized that IgHV unmutated CLL could arise early in B cell differentiation. We prospectively studied 29 patients with mutated and 88 with unmutated IgHV CLL for the presence of CD34+CD19+ cells harboring CLL chromosomal abnormalities. CD34+CD19+ cells were never detected in mutated CLL. In contrast, a small but distinct population of CD34+CD19+ cells harboring the CLL chromosomal abnormality was present in 86/88 patients with unmutated IgHV across all cytogenetic subtypes. Moreover, the CD34+CD19+ cells generated a 3.8 ± 0.7 fold CLL cell expansion over 3-4 weeks in cultures containing IL-3 and IL-2. Unmutated IgHV CLL appears to arise in CD34+ B cells, which perhaps contributes to its poorer prognosis.

Post-Transplantation Cyclophosphamide-Based Graft- versus-Host Disease Prophylaxis with Nonmyeloablative Conditioning for Blood or Marrow Transplantation for Myelofibrosis.

We describe outcomes after post-transplantation cyclophosphamide and nonmyeloablative conditioning-based allogeneic blood or marrow transplantation for myelofibrosis using matched or mismatched related or unrelated donors. The conditioning regimen consisted of fludarabine, cyclophosphamide, and total body irradiation. Forty-two patients were included, with a median age of 63 years, of whom 19% had Dynamic International Prognostic Scoring System (DIPSS)-plus intermediate-1 risk, 60% had intermediate-2 risk, and 21% had high-risk disease, and 60% had at least 1 high-risk somatic mutation. More than 90% of patients engrafted neutrophils, at a median of 19.5 days, and 7% experienced graft failure. At 1 year and 3 years, respectively, overall survival was 65% and 60%, relapse-free survival was 65% and 31%, relapse was 5% and 40%, and nonrelapse mortality was 30% and 30%. Acute graft-versus-host disease grade 3-4 was seen in 17% of patients at 1 year, and chronic graft-versus-host disease requiring systemic therapy in occurred in 12% patients. Spleen size ≥17 cm or prior splenectomy was associated with inferior relapse-free survival (hazard ratio [HR], 3.50; 95% confidence interval [CI], 1.18 to 10.37; P = .02) and higher relapse rate (subdistribution HR [SDHR] not calculable; P = .01). Age >60 years (SDHR, 0.26; 95% CI, 0.08 to 0.80, P = .02) and receipt of peripheral blood grafts (SDHR, 0.34; 95% CI, 0.11 to 0.99; P = .05) were associated with a lower risk of relapse. In our limited sample, the presence of a high-risk mutation was not statistically significantly associated with an inferior outcome, although ASXL1 was suggestive of inferior survival (SDHR, 2.36; 95% CI, 0.85 to 6.6; P = .09). Overall, this approach shows outcomes comparable those of to previously reported approaches and underscores the importance of spleen size in the evaluation of transplantation candidates.

Nonmyeloablative Allogeneic Transplantation With Post-Transplant Cyclophosphamide for Acute Myeloid Leukemia With IDH Mutations: A Single Center Experience.

INTRODUCTION: Mutations in the IDH1 or IDH2 genes are detected in approximately 20% of cases of acute myeloid leukemia (AML). Few studies have examined the impact of IDH mutations in AML on allogeneic bone marrow transplant (alloBMT) outcomes. PATIENTS AND METHODS: In this single center study, alloBMT outcomes for 61 patients with IDH-mutated (mIDH) AML were compared to those for 146 patients with IDH-wildtype (wtIDH) AML. RESULTS: Patients with mIDH AML had a 2-year overall survival (OS) of 85% (95% CI 76%-95%), 2-year relapse free survival (RFS) of 71% (95% CI 59%-85%), 1-year cumulative incidence of relapse (CIR) of 14% (95% CI 5%-23%) and a 1-year cumulative incidence of transplant related mortality (CITRM) of 3% (95% CI 0%-8%). Patients with wtIDH had a 2-year OS of 61% (95% CI 53%-70%), 2-year RFS of 58% (95% CI 50%-67%), 1-year CIR of 27% (95% CI 20%-35%), and a 1-year CITRM of 9% (95% CI 5%-14%). In a univariate analysis cox-proportional hazard model, mIDH was associated with significantly better OS (HR 0.52, 95% CI 0.29-0.96) and a trend toward better RFS (HR 0.60, 95% CI 0.35-1.01). After controlling for donor age, diagnosis, and ELN risk category, mIDH was associated with a nonsignificantly improved OS (HR 0.54, 95% CI 0.29-1.01) and RFS (HR 0.67, 95% CI 0.39-1.15). CONCLUSION: Among patients with mIDH AML, patients who received a peritransplant IDH inhibitor had improved OS (P = .03) compared to those who did not, but there was no detectable difference for RFS (P = .29).

Allogeneic Blood or Marrow Transplantation with Nonmyeloablative Conditioning and High-Dose Cyclophosphamide-Based Graft-versus-Host Disease Prophylaxis for Secondary Central Nervous System Lymphoma.

Secondary central nervous system (CNS) lymphoma is a rare and often fatal complication of non-Hodgkin lymphoma (NHL). Treatment options include radiation therapy, high-dose systemic chemotherapy, intrathecal chemotherapy, and high-dose chemotherapy with autologous stem cell rescue, but outcomes remain poor. Allogeneic blood or marrow transplantation (alloBMT) is widely used in patients with relapsed/refractory systemic NHL. We sought to understand whether a graft-versus-lymphoma effect could maintain remission in CNS disease. We reviewed outcomes in 20 consecutive patients with secondary CNS lymphoma who underwent alloBMT with nonmyeloablative conditioning using fludarabine, cyclophosphamide, and 200 cGy total body irradiation. For graft-versus-host disease prophylaxis, all patients received post-transplantation cyclophosphamide, mycophenolate mofetil, and a calcineurin inhibitor. With a median follow up of 4.1 years, the median overall survival for the entire cohort was not reached. Median progression-free survival was 3.8 years (95% confidence interval [CI], 5.3 months to not reached). The cumulative incidence of relapse was 25% (95% CI, 5% to 45%), and nonrelapse mortality was 30% (95% CI, 5% to 54%) at 4 years. Of the 5 patients who relapsed, 2 were CNS only, 1 was systemic only, and 2 were combined CNS/systemic. The use of alloBMT in CNS lymphoma merits further investigation.

Hairy cell leukemia and COVID-19 adaptation of treatment guidelines.

Standard treatment options in classic HCL (cHCL) result in high response rates and near normal life expectancy. However, the disease itself and the recommended standard treatment are associated with profound and prolonged immunosuppression, increasing susceptibility to infections and the risk for a severe course of COVID-19. The Hairy Cell Leukemia Foundation (HCLF) has recently convened experts and discussed different clinical strategies for the management of these patients. The new recommendations adapt the 2017 consensus for the diagnosis and management with cHCL to the current COVID-19 pandemic. They underline the option of active surveillance in patients with low but stable blood counts, consider the use of targeted and non-immunosuppressive agents as first-line treatment for cHCL, and give recommendations on preventive measures against COVID-19.

Moxetumomab pasudotox in heavily pre-treated patients with relapsed/refractory hairy cell leukemia (HCL): long-term follow-up from the pivotal trial.

BACKGROUND: Moxetumomab pasudotox is a recombinant CD22-targeting immunotoxin. Here, we present the long-term follow-up analysis of the pivotal, multicenter, open-label trial (NCT01829711) of moxetumomab pasudotox in patients with relapsed/refractory (R/R) hairy cell leukemia (HCL). METHODS: Eligible patients had received ≥ 2 prior systemic therapies, including ≥ 2 purine nucleoside analogs (PNAs), or ≥ 1 PNA followed by rituximab or a BRAF inhibitor. Patients received 40 µg/kg moxetumomab pasudotox intravenously on Days 1, 3, and 5 of each 28-day cycle for up to six cycles. Disease response and minimal residual disease (MRD) status were determined by blinded independent central review. The primary endpoint was durable complete response (CR), defined as achieving CR with hematologic remission (HR, blood counts for CR) lasting > 180 days. RESULTS: Eighty adult patients were treated with moxetumomab pasudotox and 63% completed six cycles. Patients had received a median of three lines of prior systemic therapy; 49% were PNA-refractory, and 38% were unfit for PNA retreatment. At a median follow-up of 24.6 months, the durable CR rate (CR with HR > 180 days) was 36% (29 patients; 95% confidence interval: 26-48%); CR with HR ≥ 360 days was 33%, and overall CR was 41%. Twenty-seven complete responders (82%) were MRD-negative (34% of all patients). CR lasting ≥ 60 months was 61%, and the median progression-free survival without the loss of HR was 71.7 months. Hemolytic uremic and capillary leak syndromes were each reported in ≤ 10% of patients, and ≤ 5% had grade 3-4 events; these events were generally reversible. No treatment-related deaths were reported. CONCLUSIONS: Moxetumomab pasudotox resulted in a high rate of durable responses and MRD negativity in heavily pre-treated patients with HCL, with a manageable safety profile. Thus, it represents a new and viable treatment option for patients with R/R HCL, who currently lack adequate therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01829711; first submitted: April 9, 2013. https://clinicaltrials.gov/ct2/show/NCT01829711.

Allogeneic transplantation for Ph+ acute lymphoblastic leukemia with posttransplantation cyclophosphamide.

Allogeneic blood or marrow transplantation (alloBMT) is standard of care for adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) in first complete remission (CR1). The routine pretransplant and posttransplant use of tyrosine kinase inhibitors (TKIs) has dramatically improved outcomes, but the optimal conditioning regimen, donor type, and TKI remain undefined. The bone marrow transplant database at Johns Hopkins was queried for adult patients with de novo Ph+ ALL who received alloBMT using posttransplantation cyclophosphamide (PTCy) as a component of graft-versus-host disease (GVHD) prophylaxis from 2008 to 2018. Among transplants for Ph+ ALL, 69 (85%) were performed in CR1, and 12 (15%) were performed in second or greater remission (CR2+). The majority of transplants (58%) were HLA haploidentical. Nearly all patients (91.4%) initiated TKI posttransplant. For patients in CR1, the 5-year relapse-free survival (RFS) was 66%. The use of nonmyeloablative conditioning, absence of measurable residual disease (MRD) according to flow cytometry at transplant, and the use of dasatinib vs imatinib at diagnosis were associated with improved overall survival (OS) and RFS. Neither donor type nor recipient age ≥60 years affected RFS. When analyzing all transplants, alloBMT in CR1 (vs CR2+) and the absence of pretransplant MRD were associated with improved RFS. Most relapses were associated with the emergence of kinase domain mutations. The cumulative incidence of grade 3 to 4 acute GVHD at 1 year was 9%, and moderate to severe chronic GVHD at 2 years was 8%. Nonmyeloablative alloBMT with PTCy for Ph+ ALL in an MRD-negative CR1 after initial treatment with dasatinib yields favorable outcomes.

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.

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.

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.