Background Chimeric antigen receptor (CAR) T cells targeting CD30 are safe and have promising activity when preceded by lymphodepleting chemotherapy. We aimed to determine the safety of anti-CD30 CAR T cells as consolidation after autologous haematopoietic stem-cell transplantation (HSCT) in patients with CD30 + lymphoma at high risk of relapse. Methods This phase 1 dose-escalation study was performed at two sites in the USA. Patients aged 3 years and older, with classical Hodgkin lymphoma or non-Hodgkin lymphoma with CD30 + disease documented by immuno histo chemistry, and a Karnofsky performance score of more than 60% planned for autologous HSCT were eligible if they were considered high risk for relapse as defined by primary refractory disease or relapse within 12 months of initial therapy or extranodal involvement at the start of pre-transplantation salvage therapy. Patients received a single infusion of CAR T cells (2 x 10(7) CAR T cells per m(2) , 1 x 10(8) CAR T cells per m(2) , or 2 x 10(8) CAR T cells per m(2) ) as consolidation after trilineage haematopoietic engraftment (defined as absolute neutrophil count >= 500 cells per mu L for 3 days, platelet count >= 25 x 10(9) platelets per L without transfusion for 5 days, and haemoglobin >= 8 g/dL without transfusion for 5 days) following carmustine, etoposide, cytarabine, and melphalan (BEAM) and HSCT. The primary endpoint was the determination of the maximum tolerated dose, which was based on the rate of dose-limiting toxicity in patients who received CAR T-cell infusion. This study is registered with ClinicalTrials.gov (NCT02663297) and enrolment is complete. Findings Between lune 7, 2016, and Nov 30, 2020, 21 patients were enrolled and 18 patients (11 with Hodgkin lymphoma, six with T-cell lymphoma, one with grey zone lymphoma) were infused with anti-CD30 CAR T cells at a median of 22 days (range 16-44) after autologous HSCT. There were no dose-limiting toxicities observed, so the highest dose tested, 2 x 10(8) CAR T cells per m 2 , was determined to be the maximum tolerated dose. One patient had grade 1 cytokine release syndrome. The most common grade 3-4 adverse events were lymphopenia (two [11%] of 18) and leukopenia (two [11%] of 18). There were no treatment-related deaths. Two patients developed secondary malignancies approximately 2 years and 25 years following treatment (one stage 4 non-small cell lung cancer and one testicular cancer), but these were judged unrelated to treatment. At a median follow-up of 482 months (IQR 275-607) postinfusion, the median progression-free survival for all treated patients (n=18) was 323 months (95% CI 46 months to not estimable) and the median progression-free survival for treated patients with Hodgkin lymphoma (n=11) has not been reached. The median overall survival for all treated patients has not been reached. Interpretation Anti-CD30 CAR T-cell infusion as consolidation after BEAM and autologous HSCT is safe, with low rates of toxicity and encouraging preliminary activity in patients with Hodgkin lymphoma at high risk of relapse, highlighting the need for larger studies to confirm these findings.

Thomas C. Shea, MD, is a retired hematologist-oncologist, researcher, and teacher at the University of North Carolina School of Medicine and UNC Lineberger Comprehensive Cancer Center. He discusses innovations and improved outcomes in cancer care in our state with NCMJ Editor-in-Chief Peter J. Morris, MD.

Our group has recently demonstrated that chimeric antigen receptor T-cell therapy targeting the CD30 antigen (CD30.CAR-T) is highly effective in patients with relapsed and refractory (r/r) classical Hodgkin lymphoma (cHL). Despite high rates of clinical response, relapses and progression were observed in a subset of patients. The objective of this study was to characterize clinical and correlative factors associated with progression-free survival (PFS) after CD30.CAR-T cell therapy. We evaluated correlatives in 27 patients with r/r cHL treated with lymphodepletion and CD30.CAR-T cells. With a median follow-up of 9.5 months, 17 patients (63%) progressed, with a median PFS of 352 days (95% confidence interval: 116-not reached), and 2 patients died (7%) with a median overall survival of not reached. High metabolic tumor volume (MTV, >60 mL) immediately before lymphodepletion and CD30.CAR-T cell infusion was associated with inferior PFS (log rank, P = .02), which persisted after adjusting for lymphodepletion and CAR-T dose (log rank, P = .01 and P = .006, respectively). In contrast, receiving bridging therapy, response to bridging therapy, CD30.CAR-T expansion/persistence, and percentage of CD3+PD-1+ lymphocytes over the first 6 weeks of therapy were not associated with differences in PFS. In summary, this study reports an association between high baseline MTV immediately before lymphodepletion and CD30.CAR-T cell infusion and worse PFS in patients with r/r cHL. This trial was registered at www.clinicaltrials.gov as #NCT02690545.

Abstract Background: Chimeric antigen receptor (CAR)-T cell therapy targeting the CD19 antigen has been effective in treating B-cell acute lymphoblastic leukemia. As CAR-T cells targeting new antigens are being explored for the treatment of other cancers in adults, parallel studies are warranted for pediatric cohorts. We have previously shown the safety and efficacy in adults of CAR-T cells targeting CD30, which is expressed in classical Hodgkin Lymphoma (HL) and in some Non-Hodgkin Lymphoma (NHL). We have therefore sought to study the feasibility and the safety of CD30.CAR-T cells in pediatric patients with relapsed/refractory CD30-expressing HL and Anaplastic Large Cell Lymphoma (ALCL). Design/Methods: Six pediatric patients (ages 9 to 17 years) with CD30+ HL (4) and NHL (2) were enrolled on two trials at the University of North Carolina. One NHL patient with ALK+ ALCL was enrolled on both trials. Two patients, one HL and one NHL, were enrolled on a phase I study and received 2x10 7 CD30.CAR-T cells/m 2 as consolidation for high-risk of relapse after autologous stem cell transplant (ASCT, NCT02663297). Five patients, 3 HL and 2 NHL, were enrolled on a phase Ib/II study and received 1x10 8 CD30.CAR-T cells/m 2, as treatment for relapsed disease, after lymphodepletion with bendamustine and fludarabine (NCT02690545). HL patients had failed multiple lines of therapies (5-6), including 2 with prior pembrolizumab, 2 with prior ASCT, and all 3 with prior brentuximab vedotin (BV) and radiation therapy. The two NHL patients both had ALCL, one was ALK positive and one was ALK negative. Both had been treated with prior BV. The ALK negative patient had been treated with 3 prior lines of therapy and the ALK positive patient had been treated with 6 lines of prior therapy including ASCT and two ALK inhibitors, crizotinib and brigatinib. The brigatinib was stopped 3 weeks prior to starting lymphodepletion. Results: CD30.CAR-T cells were successfully manufactured for all 7 patients and no differences were observed as compared to products manufactured for adults, based on cell number, transduction, potency or immunophenotype. For all patients, infusions were well-tolerated and no neurotoxicity experienced. On the post-ASCT study, 1 patient with HL and 1 with ALCL were treated. All adverse events (AE) were less than grade 4. The patient with HL remains in complete remission (CR) 41 months following therapy, while the patient with ALCL progressed. Five patients with relapsed/refractory disease (3 HL and 2 ALCL) were treated on the post-lymphodepletion study. Most grade 3 or higher AEs were anticipated hematologic toxicity secondary to lymphodepletion. The youngest HL patient on the study developed symptoms consistent with grade 2 cytokine release syndrome (CRS) and a concomitant pneumonia based on imaging, accompanied by a marked inflammatory response based on labs with maximum ferritin 9,920 ng/mL and CRP 150.7 mg/L. He responded to antibacterial agents and two doses of tocilizumab, as well as brief supplemental oxygen by nasal cannula. He did not require vasopressors. One patient with ALK+ ALCL had symptoms compatible with CRS and macrophage activation syndrome (maximum ferritin >100,000 ng/mL and CRP 39.7 mg/L), which were ultimately determined to be secondary to progressive disease, confirmed at autopsy 5 weeks post therapy. The other four patients (3 HL and 1 ALCL) achieved CR and remain in CR 4 to 27 months post CAR-T cell infusion. Of note, 2 of the HL patients chose to come off study while in CR to receive treatment with checkpoint inhibitor therapy. Conclusion: Our studies show that CD30.CAR-T cells are well tolerated in pediatric patients. CRs were observed in all heavily pre-treated and refractory HL patients, highlighting the potential of this strategy. All patients treated on both studies had previously received BV, which suggests CD30.CAR-T cells are effective even post BV progression. We continue to investigate how to better tailor CD30.CAR-T cells in NHL given the need for better therapies in ALCL, which is often aggressive at relapse. One patient with ALK negative ALCL remains in CR while the patient with ALK+ ALCL had rapid relapse. After study initiation, UNC entered into a research collaboration with Tessa Therapeutics. Disclosures Savoldo: Tessa: Patents & Royalties: Approach for CD30.CAR-T Cells for Hodgkin Lymphoma. Dotti: Tessa: Patents & Royalties: Approach for CD30.CAR-T Cells for Hodgkin Lymphoma. Grover: Tessa: Consultancy; Kite: Other: Advisory Board; Novartis: Consultancy; Genentech: Research Funding; ADC: Other: Advisory Board. Morrison: Vesselon: Consultancy. Riches: Jazz Pharmaceuticals: Other: Payment; ATARA Biotherapeutics: Other: Payment; BioIntelect: Membership on an entity's Board of Directors or advisory committees. Serody: Tessa: Patents & Royalties: Approach for CD30.CAR-T Cells for Hodgkin Lymphoma.

OBJECTIVE:To determine if high dose intravenous (IV) thiamine can prevent delirium during hospitalization following allogeneic HSCT. Secondarily, we evaluated the effects of high dose IV thiamine on thiamine levels and explored risk factors for delirium. METHODS:Randomized, double-blind, placebo-controlled trial in patients undergoing allogeneic HSCT at a U.S. academic medical center between October 2017 and March 2020. 64 participants were randomized 1:1 to thiamine 200 mg IV three times daily for 7 days or placebo. We used the Delirium Rating Scale to assess for delirium. Delirium incidence was compared between groups using the chi-square test. Group differences in time to onset and duration of delirium were compared using the Kaplan-Meier method. Fisher's Exact and Wilcoxon Rank Sum tests were used to examine associations between pre-transplantation variables and delirium. RESULTS:61 participants were analyzed. Delirium incidence (25% vs. 21%, Chi-square (df = 1) = 0.12, p = 0.73), time to onset, duration, and severity were not different between study arms. Immediately following the intervention, thiamine levels were higher in the thiamine arm (275 vs. 73 nmol/L, t-test (df = 57) = 13.63, p < 0.0001), but not predictive of delirium. Variables associated with delirium in our sample included disease severity, corticosteroid exposure, infection, and pre-transplantation markers of nutrition. CONCLUSION:High dose IV thiamine did not prevent delirium in patients receiving allogeneic HSCT. Given the multiple contributors to delirium in this population, further research regarding the efficacy of multicomponent interventions may be needed. TRIAL REGISTRATION:Clinical Trials NCT03263442. FUNDING:Rising Tide Foundation for Clinical Cancer Research.

The authors have no conflict of interest to declare. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Immunocompromised individuals, particularly autologous hematopoietic stem cell transplant (auHSCT) recipients, are at high risk for herpes zoster (HZ). We provide an in-depth description of humoral and cell-mediated immune (CMI) responses by age (protocol-defined) or underlying disease (post-hoc) as well as efficacy by underlying disease (post-hoc) of the adjuvanted recombinant zoster vaccine (RZV) in a randomized observer-blind phase III trial (ZOE-HSCT, NCT01610414). 1846 adult auHSCT recipients were randomized to receive a first dose of either RZV or placebo 50–70 days post-auHSCT, followed by the second dose at 1–2 months (M) later. In cohorts of 114–1721 participants, at 1 M post-second vaccine dose: Anti-gE antibody geometric mean concentrations (GMCs) and median gE-specific CD4[2+] T-cell frequencies (CD4 T cells expressing ≥2 of four assessed activation markers) were similar between 18–49 and ≥50-year-olds. Despite lower anti-gE antibody GMCs in non-Hodgkin B-cell lymphoma (NHBCL) patients, CD4[2+] T-cell frequencies were similar between NHBCL and other underlying diseases. The proportion of polyfunctional CD4 T cells increased over time, accounting for 79.6% of gE-specific CD4 T cells at 24 M post-dose two. Vaccine efficacy against HZ ranged between 42.5% and 82.5% across underlying diseases and was statistically significant in NHBCL and multiple myeloma patients. In conclusion, two RZV doses administered early post-auHSCT induced robust, persistent, and polyfunctional gE-specific immune responses. Efficacy against HZ was also high in NHBCL patients despite the lower humoral response.

PURPOSEChimeric antigen receptor (CAR) T-cell therapy of B-cell malignancies has proved to be effective. We show how the same approach of CAR T cells specific for CD30 (CD30.CAR-Ts) can be used to treat Hodgkin lymphoma (HL).METHODSWe conducted 2 parallel phase I/II studies (ClinicalTrials.gov identifiers: NCT02690545 and NCT02917083) at 2 independent centers involving patients with relapsed or refractory HL and administered CD30.CAR-Ts after lymphodepletion with either bendamustine alone, bendamustine and fludarabine, or cyclophosphamide and fludarabine. The primary end point was safety.RESULTSForty-one patients received CD30.CAR-Ts. Treated patients had a median of 7 prior lines of therapy (range, 2-23), including brentuximab vedotin, checkpoint inhibitors, and autologous or allogeneic stem cell transplantation. The most common toxicities were grade 3 or higher hematologic adverse events. Cytokine release syndrome was observed in 10 patients, all of which were grade 1. No neurologic toxicity was observed. The overall response rate in the 32 patients with active disease who received fludarabine-based lymphodepletion was 72%, including 19 patients (59%) with complete response. With a median follow-up of 533 days, the 1-year progression-free survival and overall survival for all evaluable patients were 36% (95% CI, 21% to 51%) and 94% (95% CI, 79% to 99%), respectively. CAR-T cell expansion in vivo was cell dose dependent.CONCLUSIONHeavily pretreated patients with relapsed or refractory HL who received fludarabine-based lymphodepletion followed by CD30.CAR-Ts had a high rate of durable responses with an excellent safety profile, highlighting the feasibility of extending CAR-T cell therapies beyond canonical B-cell malignancies.

Cognitive impairment is common and consequential in patients with cancer who undergo allogeneic hematopoietic stem cell transplantation (HSCT). However, there is no standard of care for evaluating cognition in patients prior to or after receiving HSCT, and it is not known which patients are at highest risk for cognitive impairment. The objectives of this study were to describe cognitive function in patients prior to allogeneic HSCT and identify demographic, disease-related, and psychosocial factors associated with cognitive function. Prior to HSCT, participants completed the Montreal Cognitive Assessment (MoCA). We assessed bivariable associations between continuous MoCA scores and demographic, disease-related, and psychosocial variables using linear regression. Variables significant at the p < 0.2 level were adjusted for age, sex, and years of education in multiple linear regression analyses. Over 50% of participants demonstrated evidence of cognitive impairment (MoCA < 26) prior to transplantation. When adjusted for demographic variables, two characteristics were significantly associated with worse cognitive function: the hematopoietic cell transplantation-comorbidity index score (p = 0.01) and history of alcohol or substance abuse (p = 0.02). Pre-HSCT cancer and cancer treatment–specific variables were not associated with cognitive function. Cognitive impairment is common in patients scheduled to receive HSCT. Pre-transplantation evaluation of medical comorbidities and history of substance abuse may be important in identifying patients at risk for cognitive impairment. Further research characterizing the trajectory and impact of cognitive impairment on patient symptom burden and function may help improve outcomes.

Approximately 90% of limited-stage Hodgkin lymphoma (HL) patients are projected to be cured with standard therapy, but many do not live their expected life span because of late treatment-related complications. New treatment paradigms are needed to reduce the use of radiation therapy (RT) as well as conventional chemotherapy drugs while improving upon current standard-of-care survival outcomes. In this phase 2 multicenter study, patients with non-bulky limited-stage HL received doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by brentuximab vedotin (BV) consolidation. Forty-one patients were enrolled, and patient characteristics included median age of 29 years (range, 19 to 67 years), 58% were female, 45% had unfavorable disease, and 98% had stage II disease. Based on positron emission tomography (PET)-based risk stratification, patients received 2 to 6 cycles of ABVD followed by 6 cycles of BV. After ABVD followed by BV, 95% of evaluable patients (37 out of 39; 95% confidence interval [CI], 83%-99%) achieved PET-negative status. In the intent-to-treat patient population, the estimated 3-year progression-free survival (PFS) rate was 92%, and the overall survival (OS) rate was 97%, with a median follow-up of 47 months. All 37 patients who achieved negative PET status after BV consolidation effectively avoided RT and remain in remission with estimated 3-year PFS and OS rates of 100%. In conclusion, BV demonstrates encouraging clinical activity when it follows ABVD therapy in limited-stage HL. Early incorporation of BV may reduce the use of RT as well as conventional chemotherapy drugs while achieving favorable survival outcomes in risk-stratified patients with non-bulky limited-stage HL.

Tacrolimus exhibits high inter-patient pharmacokinetics (PK) variability, as well as a narrow therapeutic index, and therefore requires therapeutic drug monitoring. Germline mutations in cytochrome P450 isoforms 4 and 5 genes (CYP3A4/5) and the ATP-binding cassette B1 gene (ABCB1) may contribute to interindividual tacrolimus PK variability, which may impact clinical outcomes among allogeneic hematopoietic stem cell transplantation (HSCT) patients. In this study, 252 adult patients who received tacrolimus for acute graft versus host disease (aGVHD) prophylaxis after allogeneic HSCT were genotyped to evaluate if germline genetic variants associated with tacrolimus PK and pharmacodynamic (PD) variability. Significant associations were detected between germline variants in CYP3A4/5 and ABCB1 and PK endpoints (e.g., median steady-state tacrolimus concentrations and time to goal tacrolimus concentration). However, significant associations were not observed between CYP3A4/5 or ABCB1 germline variants and PD endpoints (e.g., aGVHD and treatment-emergent nephrotoxicity). Decreased age and CYP3A5*1/*1 genotype were independently associated with subtherapeutic tacrolimus trough concentrations while CYP3A5*1*3 or CYP3A5*3/*3 genotypes, myeloablative allogeneic HSCT conditioning regimen (MAC) and increased weight were independently associated with supratherapeutic tacrolimus trough concentrations. Future lines of prospective research inquiry are warranted to use both germline genetic and clinical data to develop precision dosing tools that will optimize both tacrolimus dosing and clinical outcomes among adult HSCT patients.

Allogeneic hematopoietic cell transplantation (alloHCT) is a life-saving technology that can cure otherwise incurable diseases, but imposes significant physiologic stress upon recipients. This stress leads to short-term toxicity and mid- to long-term physical function impairment in some recipients. Exercise interventions have demonstrated preliminary efficacy in preserving physical function in HCT recipients, but the role of these interventions prior to HCT (prehabilitative) is less known. We tested a 5- to 12-week, prehabilitative higher intensity home-based aerobic exercise intervention in a randomized study of alloHCT candidates. Of 113 patients screened, 34 were randomized to control or intervention groups, 16 underwent pre- and post-intervention peak oxygen consumption (VO2peak) testing, and 12 underwent pre- and post-intervention 6-min walk distance (6MWD) testing. No significant differences in VO2peak or 6MWD were seen pre- to post-intervention between intervention and control groups, but final numbers of evaluable participants in each group were too small to draw inferences regarding the efficacy of the intervention. We conclude that the design of our prehabilitative intervention was not feasible in this pilot randomized study, and make recommendations regarding the design of future exercise intervention studies in alloHCT.

Plerixafor is a hematopoietic stem cell mobilizing agent used in combination with granulocyte-colony stimulating factor to improve collection for autologous stem cell transplantation. Despite a recommendation for administration 11 h prior to apheresis per package labeling, logistical challenges lead many institutions to administer plerixafor at an extended interval. The purpose of this study was to determine if plerixafor effectively and efficiently mobilizes CD34+ cells when given at an extended interval prior to apheresis. This was a retrospective evaluation of adult patients who received plerixafor based on an algorithm reserving daily plerixafor only for patients with a pre-apheresis CD34+ count of < 20 cells/µL (pre-apheresis plerixafor) or with a low CD34+ yield after the first apheresis session (rescue plerixafor). The primary outcome was achievement of a disease-specific collection goal of ≥ 6 ×106 CD34+ cells/kg for multiple myeloma and ≥ 4 ×106 CD34+ cells/kg for lymphoma. The mean interval between plerixafor administration and apheresis was 17 h in this study. Despite this extended interval, 64% of patients met their disease-specific collection goal. A minimum collection goal of ≥ 2 ×106 CD34+ cells/kg was achieved by 95% of patients. Mobilization remained efficient with a median of two days to complete collection. Based on this data, plerixafor effectively and efficiently mobilizes CD34+ cells when given at an extended interval prior to apheresis.

BACKGROUND:Delirium is a highly prevalent and preventable neuropsychiatric condition with major health consequences. Thiamine deficiency is a well-established cause of delirium in those with chronic, severe alcoholism, but there remains an underappreciation of its significance in non-alcoholic populations, including patients with cancer. Treatment of suspected thiamine-related mental status changes with high dose intravenous (IV) thiamine has preliminary evidence for improving a variety of cognitive symptoms in oncology inpatient settings but has never been studied for the prevention of delirium in any population.OBJECTIVES:The primary objective of this clinical trial is to determine if high dose IV thiamine can prevent delirium in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) for treatment of cancer. Secondary objectives are to determine if thiamine status is predictive of delirium onset and if high dose IV thiamine can attenuate the deleterious impact of delirium on health-related quality of life (HRQOL), functional status, and long-term neuropsychiatric outcomes.METHODS:In this phase II study, we are recruiting 60 patients undergoing allogeneic HSCT, randomizing them to treatment with high dose IV thiamine (n = 30) versus placebo (n = 30), and systematically evaluating all participants for delirium and related comorbidities. We use the Delirium Rating Scale to measure the severity and duration of delirium during hospitalization for HSCT. We obtain thiamine levels weekly during the transplantation hospitalization. We assess HRQOL, functional status, depression, post-traumatic stress symptoms, and cognitive function prior to and at one, three, and six months after transplantation.

CALGB (Alliance) 100001 was a phase II study evaluating autologous stem cell transplant (ASCT) followed by nonmyeloablative allogeneic stem cell transplant (alloSCT) in patients with multiple myeloma who had received no more than 18 months of prior therapy and had experienced no more than 1 prior progression event. Conditioning for ASCT was with high-dose melphalan (200 mg/m2). The alloSCT reduced-intensity conditioning (RIC) regimen consisted of fludarabine (30 mg/m2/d i.v. on days -7 through -3) and cyclophosphamide (1 g/m2/d i.v. on days -4 through -3). The primary objective was to determine the 6-month post-alloSCT treatment-related mortality (TRM) rate. Additional objectives included determining the proportion of patients who could complete this tandem ASCT-alloSCT approach in a cooperative group setting, overall response rates, rates of donor chimerism, rates of graft-versus-host disease (GVHD), disease-free survival, and overall survival (OS). Sixty patients were enrolled, of whom 57 (95%) completed ASCT and 49 (82%) completed tandem ASCT-alloSCT. The TRM rate was 2% (1/49; 90% confidence interval, 0.10% to 9.3%). Moderate to severe (grades 2 to 3) acute GVHD was observed in 13 of 49 alloSCT patients (27%). One patient died due to GVHD within 9 months of alloSCT. Twenty-seven of the 49 patients (55%) who underwent alloSCT reported chronic GVHD as either limited (15/49; 31%) or extensive (12/49; 24%) in the first year post-alloSCT and prior to the start of nonprotocol therapy for progressive disease. With a median follow-up for survival of 11 years, the median OS time is 6.6 years and the median time to disease progression is 3.6 years. Similar to other studies, this study confirmed that tandem ASCT/alloSCT is associated with durable disease control in a subset of patients. This study demonstrated the feasibility of performing tandem ASCT/alloSCT in a cooperative group setting and determined that a fludarabine/cyclophosphamide RIC regimen is associated with a very low TRM rate.

Relapse remains the major cause of death in older patients transplanted for acute myeloid leukemia (AML) in first complete remission or for patients with advanced myelodysplastic syndrome (MDS) at any age. Conventional myeloablative conditioning followed by allogeneic blood or marrow transplantation is associated with significantly less relapse compared with reduced-intensity conditioning when performed in younger patients with AML or MDS, but the toxicity of this approach in older patients is prohibitive. We hypothesized that pharmacokinetic targeting to optimize busulfan (BU) exposure, combined with the administration of azacitidine (AZA) post-transplant would mitigate the risk of relapse while reducing nonrelapse mortality and ultimately improve progression-free survival (PFS). On this phase II multicenter study, 63 patients (40 unrelated donors and 23 matched related donors) received a uniform conditioning regimen consisting of fludarabine i.v. (days -7 to -3), BU targeted to a daily area under the curve (AUC) of 4000 μM/min (days -6 to -3) after the administration of a 25-mg/m2 i.v. test dose on 1 day between days -14 to -9, and antithymocyte globulin (days -6, -5, and -4 (2 doses for matched related donors and 3 for matched unrelated donors only). Beginning on days +42 to +90, all patients were planned to receive up to 6 monthly cycles of AZA at 32 mg/m2 subcutaneously for 5 days. The median age was 62 years (range, 44 to 74); 13 had AML and 50 had MDS; 87% of patients were within 20% of the target AUC based on a validation sample. Forty-one patients (65%) started AZA at a median of 61 days (range, 43 to 91) post-transplant, and 17 patients (41%) completed all 6 cycles of AZA. The cumulative incidence of nonrelapse mortality at 2 years was 33.4% (95% confidence interval [CI], 22%-45%). The cumulative incidence of relapse was 25% (95% CI, 15%-37%) at 2 years. With a median follow-up of 58.9 months, the estimated PFS probability at 2 years and 5 years after transplantation was 41.2% (80% CI, 33.9%-49.9%) and 26.9% (80% CI, 20.4%-35.5%), respectively, for the entire group with a median PFS of 15.8 months (95% CI, 6.7 to 28.3). The probability of overall survival at 2 and 5 years was 45.7% (95% CI, 34.9%-59.9%) and 31.2% (95% CI, 21.3% to 45.8%), respectively, for the entire group with a median overall survival of 19.2 months (95% CI, 8.7 to 37.5). In summary, we demonstrated the feasibility of a novel reduced-intensity conditioning regimen with test dose BU targeted to an AUC of 4000 μM/min. The feasibility of AZA in this setting appears to be limited if applied to an unselected population of older hematopoietic stem cell transplantation recipients. (ClinicalTrials.gov Identifier: NCT01168219.).

Background: Acute graft versus host disease (aGVHD) occurs in approximately 50% of patients receiving allogeneic hematopoietic stem cell transplant (HSCT) with standard GVHD prophylaxis regimens and is a significant contributor to morbidity and non-relapse mortality (NRM). There are currently no FDA approved therapies for the initial treatment of newly diagnosed aGVHD. T effector cells (Teff), particularly CD4+ T helper cells, play a central role in the pathogenesis of aGVHD. CD6 is a co-stimulatory receptor, predominantly expressed on CD4+ T helper cells, that binds to activated leukocyte cell adhesion molecule (ALCAM), a ligand expressed on antigen presenting cells and various epithelial and endothelial tissues. The CD6-ALCAM pathway plays an integral role in modulating T cell activation and trafficking and is central to immune mediated inflammation. Previous studies by Soiffer et al. in patients receiving allogeneic bone marrow transplants had shown that depleting CD6+ T cells ex-vivo in donor bone marrow using T-12, an anti-CD6 monoclonal antibody (mAb), as a sole method for GVHD prophylaxis lowered the incidence of acute and chronic GVHD. EQ001 (itolizumab) is a humanized IgG1 mAb that binds to CD6 and blocks the interaction with ALCAM and inhibits both the activity and trafficking of T cells without causing T cell depletion. Itolizumab has s previously been developed and is approved for the treatment of Psoriasis in India. The potential effectiveness of an anti-CD6 mAb targeted approach in treating aGVHD is supported by data from pre-clinical models evaluating the prevention and treatment of GVHD with EQ001. The objective of this study is to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and clinical activity of EQ001 in subjects with newly diagnosed aGVHD. Study Design and Methods: This is a multi-center Phase 1b/2 study (NCT03763318) of EQ001 in subjects with aGVHD. Part A (Phase 1b) of the study is an open-label, multiple ascending dose study of EQ001 in adults with newly diagnosed High Risk (MacMillan Criteria) aGVHD following HSCT. Approximately 24 subjects will be enrolled in successive cohorts of 3 to 6 adult subjects using a standard 3 + 3 dose escalation design. For each cohort, subjects will receive EQ001 administered intravenously (IV) every two weeks for five doses with corticosteroids (CS) tapered over the treatment period. A total of four dose levels will be tested ranging from 0.4 mg/kg to 2.4 mg/kg, and subjects will be followed for an additional 10 months after study treatment is completed. The primary objective of Part A is to evaluate safety and tolerability of EQ001. Secondary objectives include an evaluation of PK, PD (including CD6 receptor occupancy, changes in inflammatory cytokines and novel gut biomarkers [ST2, REG3α], and changes in Teff/T regulatory cells populations), and clinical activity (overall aGVHD response rates on Day 29, durability of the response at Day 57 and up to 1 year, cumulative incidence of NRM, rates of chronic GVHD, and CS dose requirements). Data from Part A will inform the dose selection for Part B (Phase 2) of the study. Enrollment to Part A is ongoing. Part B is a double-blind, placebo-controlled study in subjects (age ≥12) with newly diagnosed Grade II-IV aGVHD. Approximately 60 subjects will be randomized in a 2:1 ratio to either treatment with EQ001 (n=40) or placebo (n=20) in addition to and within 72 hours of the first dose of CS. EQ001 or placebo will be administered IV every two weeks for five doses, and subjects will be followed for an additional 10 months after the last dose of study treatment. The primary objective of Part B is to evaluate the overall response rate of aGVHD in patients treated with EQ001 versus placebo. Secondary objectives include an evaluation of safety and other clinical endpoints. The primary endpoint is the overall response rate at Day 29 as defined by a complete response, very good partial response or partial response. Additional clinical endpoints include assessment of NRM, chronic GVHD rates, and CS dose requirements. Conclusion: Inhibiting the CD6-ALCAM pathway with EQ001 represents a unique and promising approach for the treatment of aGVHD following HSCT by inhibiting both the activity and trafficking of T cells. This is the first clinical study to examine the effects of an anti-CD6 therapy for the treatment of patients with newly diagnosed aGVHD. Disclosures Koreth: Equillium: Consultancy; Cugene: Consultancy; Amgen: Consultancy. Shea:Jazz: Consultancy; Amgen: Consultancy; Merck: Consultancy. Jagasia:Kadmon: Consultancy; Incyte: Consultancy; Janssen: Research Funding. Waller:Pharmacyclics: Other: Travel expenses, Research Funding; Cerus Corporation: Other: Stock, Patents & Royalties; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Chimerix: Other: Stock; Cambium Oncology: Patents & Royalties: Patents, royalties or other intellectual property ; Amgen: Consultancy; Kalytera: Consultancy. Nakamura:Celgene: Other: support for an academic seminar in a university in Japan; Merck: Membership on an entity's Board of Directors or advisory committees; Alexion: Other: support to a lecture at a Japan Society of Transfusion/Cellular Therapy meeting ; Kirin Kyowa: Other: support for an academic seminar in a university in Japan. Ng:Equillium: Employment, Equity Ownership. Sonnemann:Equillium Inc.: Employment. Light:Equillium Inc.: Consultancy. Nanayakkara:Equillium Inc.: Consultancy. Essayan:Equillium Inc.: Consultancy. Rothman:Equillium Inc.: Employment, Equity Ownership. Connelly:Equillium: Employment, Equity Ownership. Polu:Equillium Inc.: Employment, Equity Ownership. Kean:HiFiBio: Consultancy; BlueBirdBio: Research Funding; Gilead: Research Funding; Regeneron: Research Funding; EMDSerono: Consultancy; FortySeven: Consultancy; Magenta: Research Funding; Kymab: Consultancy; Jazz: Research Funding; Bristol Meyers Squibb: Patents & Royalties, Research Funding. Ritz:Draper Labs: Consultancy; Talaris Therapeutics: Consultancy; TScan Therapeutics: Consultancy; Equillium: Research Funding; Merck: Research Funding; Kite Pharma: Research Funding; Aleta Biotherapeutics: Consultancy; Celgene: Consultancy; Avrobio: Consultancy; LifeVault Bio: Consultancy. Soiffer:Gilead, Mana therapeutic, Cugene, Jazz: Consultancy; Juno, kiadis: Membership on an entity's Board of Directors or advisory committees, Other: DSMB; Kiadis: Other: supervisory board; Mana therapeutic: Consultancy; Cugene: Consultancy; Jazz: Consultancy. Cutler:Kadmon: Consultancy; Omeros: Consultancy; ElsaLys: Consultancy; BiolineRx: Other: DSMB; Cellect: Other: DSMB; Kalytera: Other: DSMB; Incyte: Consultancy; Genentech: Consultancy; Jazz: Consultancy; BMS: Consultancy; Fate Therapeutics: Consultancy; Pharmacyclics: Consultancy. OffLabel Disclosure: EQ001 (itolizumab) is an investigational agent being developed for the treatment of acute GVHD. Itolizumab has not received regulatory approval for the treatment of GVHD. The abstract being submitted describes the study design for the phase 1b/2 study. No data is being presented.