Long-term outcomes of patients with large B-cell lymphoma treated with axicabtagene ciloleucel and prophylactic corticosteroids

ZUMA-1 safety management cohort 6 investigated the impact of prophylactic corticosteroids and earlier corticosteroids and/or tocilizumab on the incidence and severity of cytokine release syndrome (CRS) and neurologic events (NEs) following axicabtagene ciloleucel (axi-cel) in patients with relapsed/refractory large B-cell lymphoma (R/R LBCL). Prior analyses of cohort 6 with limited follow-up demonstrated no Grade ≥3 CRS, a low rate of NEs, and high response rates, without negatively impacting axi-cel pharmacokinetics. Herein, long-term outcomes of cohort 6 (N = 40) are reported (median follow-up, 26.9 months). Since the 1-year analysis (Oluwole, et al. Blood. 2022;138[suppl 1]:2832), no new CRS was reported. Two new NEs occurred in two patients (Grade 2 dementia unrelated to axi-cel; Grade 5 axi-cel-related leukoencephalopathy). Six new infections and eight deaths (five progressive disease; one leukoencephalopathy; two COVID-19) occurred. Objective and complete response rates remained at 95% and 80%, respectively. Median duration of response and progression-free survival were reached at 25.9 and 26.8 months, respectively. Median overall survival has not yet been reached. Eighteen patients (45%) remained in ongoing response at data cutoff. With ≥2 years of follow-up, prophylactic corticosteroids and earlier corticosteroids and/or tocilizumab continued to demonstrate CRS improvement without compromising efficacy outcomes, which remained high and durable.

Bridging therapy with axicabtagene ciloleucel for large B-cell lymphoma: results from the US Lymphoma CAR-T Consortium

ABSTRACT

During the manufacturing period of autologous chimeric antigen receptor (CAR) T-cell therapy, patients may experience a decline in their condition due to cancer progression. In this study, we investigated the impact of bridging therapy (BT) on the outcome of patients with relapsed/refractory large B-cell lymphoma who received antilymphoma treatment between leukapheresis and axicabtagene ciloleucel (axi-cel) infusion. We conducted our analysis using data from the multicenter US Lymphoma CAR-T Consortium, with a median follow-up of 33 months (range, 4.3-42.1). Out of the 298 patients who underwent leukapheresis, 275 patients received axi-cel. A total 52% of patients (n = 143) who received BT had a higher baseline risk profile than patients who did not receive BT, and these patients, as a group, had inferior outcomes compared with those who did not receive BT. However, after propensity score matching between the 2 groups, there were no statistically significant differences in overall response rate (77% vs 87%; P = .13), complete response rate (58% vs 70%; P = .1), progression-free survival (hazard ratio [HR], 1.25; P = .23), and overall survival (HR, 1.39; P=.09) between the BT group and the no-BT group, respectively. Analyzing the effects of BT in the whole cohort that underwent leukapheresis regardless of receiving axi-cel (intention-to-treat analysis) showed similar results. Radiation BT resulted in outcomes similar to those observed with nonradiation BT. Our findings suggest that BT may be safe without a significant impact on long-term survival for patients who require disease stabilization during the manufacturing period. Moreover, our results suggest that there is no clear advantage to using radiation-based BT over nonradiation-based BT.

False-Positive Human Immunodeficiency Virus Nucleic Acid Amplification Test After Chimeric Antigen Receptor T-Cell Therapy With Ciltacabtagene Autoleucel

Chimeric antigen receptor (CAR) T-cell therapy has emerged as a novel therapeutic option for hematologic malignancies. Human immunodeficiency virus (HIV) nucleic acid amplification tests (NAATs) amplifying 5' long terminal repeat and gag genes cross-react with lentiviral vector-based CAR T-cell products. Cross-reactivity between CAR T-cell products and HIV NAATs may lead to false-positive test results.

Allogeneic stem cell transplant outcomes between TBI-containing reduced intensity and myeloablative conditioning regimens for ALL in complete remission

Total-body irradiation (TBI)-based conditioning regimen is preferred in acute lymphoblastic leukemia (ALL). We retrospectively evaluated allogeneic stem cell transplant (alloSCT) outcomes of 86 adult ALL patients in complete remission (CR) who received TBI-containing reduced intensity (RIC) (Flu/Mel/TBI = 31) and myeloablative conditioning (MAC) (VP16/TBI = 47; CY/TBI = 8) between January 2005 and December 2019. All patients received peripheral blood allografts. Patients in the RIC group were older than the MAC group (61 years old versus 36 years, p < .001). Donor was 8/8 HLA-matched in 83% and unrelated in 65% of patients. Three-year survival was 56.04% for RIC and 69.9% for MAC (HR 0.64; p = .19). Propensity score-based multivariable Cox analyses (PSCA) did not demonstrate any difference in grade III-IV acute graft versus host disease (GVHD) (SHR 1.23, p = .91), chronic GVHD (SHR 0.92, p = .88), survival (HR 0.94, p = .92), and relapse-free survival (HR 0.66, p = .47) between both groups, while relapse rate was lower (SHR 0.21, p = .02) for MAC compared to RIC. Our study did not demonstrate any difference in survival for TBI-containing RIC and MAC alloSCT for adult ALL in CR.

Five-year follow-up of ZUMA-1 supports the curative potential of axicabtagene ciloleucel in refractory large B-cell lymphoma

In phase 2 of ZUMA-1, a single-arm, multicenter, registrational trial, axicabtagene ciloleucel (axi-cel) autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy demonstrated durable responses at 2 years in patients with refractory large B-cell lymphoma (LBCL). Here, we assessed outcomes in ZUMA-1 after 5 years of follow-up. Eligible adults received lymphodepleting chemotherapy followed by axi-cel (2 × 106 cells per kg). Investigator-assessed response, survival, safety, and pharmacokinetics were assessed in patients who had received treatment. The objective response rate in these 101 patients was 83% (58% complete response rate); with a median follow-up of 63.1 months, responses were ongoing in 31% of patients at data cutoff. Median overall survival (OS) was 25.8 months, and the estimated 5-year OS rate was 42.6%. Disease-specific survival (excluding deaths unrelated to disease progression) estimated at 5 years was 51.0%. No new serious adverse events or deaths related to axi-cel were observed after additional follow-up. Peripheral blood B cells were detectable in all evaluable patients at 3 years with polyclonal B-cell recovery in 91% of patients. Ongoing responses at 60 months were associated with early CAR T-cell expansion. In conclusion, this 5-year follow-up analysis of ZUMA-1 demonstrates sustained overall and disease-specific survival, with no new safety signals in patients with refractory LBCL. Protracted B-cell aplasia was not required for durable responses. These findings support the curative potential of axi-cel in a subset of patients with aggressive B-cell lymphomas. This trial was registered at ClinicalTrials.gov, as #NCT02348216.

Brexucabtagene Autoleucel for Relapsed or Refractory Mantle Cell Lymphoma in Standard-of-Care Practice: Results From the US Lymphoma CAR T Consortium

PURPOSE

Brexucabtagene autoleucel (brexu-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for relapsed/refractory mantle cell lymphoma (MCL). This therapy was approved on the basis of the single-arm phase II ZUMA-2 trial, which showed best overall and complete response rates of 91% and 68%, respectively. We report clinical outcomes with brexu-cel in the standard-of-care setting for the approved indication.

PATIENTS AND METHODS

Patients who underwent leukapheresis between August 1, 2020 and December 31, 2021, at 16 US institutions, with an intent to manufacture commercial brexu-cel for relapsed/refractory MCL, were included. Patient data were collected for analyses of responses, outcomes, and toxicities as per standard guidelines.

RESULTS

Of 189 patients who underwent leukapheresis, 168 (89%) received brexu-cel infusion. Of leukapheresed patients, 79% would not have met ZUMA-2 eligibility criteria. Best overall and complete response rates were 90% and 82%, respectively. At a median follow-up of 14.3 months after infusion, the estimates for 6- and 12-month progression-free survival (PFS) were 69% (95% CI, 61 to 75) and 59% (95% CI, 51 to 66), respectively. The nonrelapse mortality was 9.1% at 1 year, primarily because of infections. Grade 3 or higher cytokine release syndrome and neurotoxicity occurred in 8% and 32%, respectively. In univariable analysis, high-risk simplified MCL international prognostic index, high Ki-67, TP53 aberration, complex karyotype, and blastoid/pleomorphic variant were associated with shorter PFS after brexu-cel infusion. Patients with recent bendamustine exposure (within 24 months before leukapheresis) had shorter PFS and overall survival after leukapheresis in intention-to-treat univariable analysis.

CONCLUSION

In the standard-of-care setting, the efficacy and toxicity of brexu-cel were consistent with those reported in the ZUMA-2 trial. Tumor-intrinsic features of MCL, and possibly recent bendamustine exposure, may be associated with inferior efficacy outcomes.

Ciltacabtagene Autoleucel, an Anti-B-cell Maturation Antigen Chimeric Antigen Receptor T-Cell Therapy, for Relapsed/Refractory Multiple Myeloma: CARTITUDE-1 2-Year Follow-Up

PURPOSE

CARTITUDE-1, a phase Ib/II study evaluating the safety and efficacy of ciltacabtagene autoleucel (cilta-cel) in heavily pretreated patients with relapsed/refractory multiple myeloma, yielded early, deep, and durable responses at 12 months. Here, we present updated results 2 years after last patient in (median follow-up [MFU] approximately 28 months), including analyses of high-risk patient subgroups.

METHODS

Eligible patients had relapsed/refractory multiple myeloma, had received ≥ 3 prior lines of therapy or were double refractory to a proteasome inhibitor and immunomodulatory drug and had received prior proteasome inhibitor, immunomodulatory drug, and anti-CD38 therapy. Patients received a single cilta-cel infusion 5-7 days after lymphodepletion. Responses were assessed by an independent review committee.

RESULTS

At a MFU of 27.7 months (N = 97), the overall response rate was 97.9% (95% CI, 92.7 to 99.7); 82.5% (95% CI, 73.4 to 89.4) of patients achieved a stringent complete response. Median duration of response was not estimable. Median progression-free survival (PFS) and overall survival (OS) were not reached; 27-month PFS and OS rates were 54.9% (95% CI, 44.0 to 64.6) and 70.4% (95% CI, 60.1 to 78.6), respectively. Overall response rates were high across all subgroups (95.1%-100%). Duration of response, PFS, and/or OS were shorter in patients with high-risk cytogenetics, International Staging System stage III, high tumor burden, or plasmacytomas. The safety profile was manageable with no new cilta-cel-related cytokine release syndrome and one new case of parkinsonism (day 914 after cilta-cel) since the last report.

CONCLUSION

At approximately 28 months MFU, patients treated with cilta-cel maintained deep and durable responses, observed in both standard and high-risk subgroups. The risk/benefit profile of cilta-cel remained favorable with longer follow-up.

Epidemiology and Predictors of 30-Day Readmission in CAR-T Cell Therapy Recipients

The novel cellular immunotherapy using chimeric antigen receptor (CAR) T cells has transformed the management of several previously incurable hematologic malignancies. Since the first CAR-T cell product was approved by the Food and Drug Administration in 2017, five additional products have been approved for various hematologic malignancies. Although there is now more experience with outpatient administration, CAR-T therapy was initially delivered in an inpatient setting. The unique complications of cytokine release syndrome (CRS) and neurologic side effects (commonly known as immune effector cell-associated neurotoxicity syndrome [ICANS]), along with a higher risk for infection, increase the risk for hospital readmission. Given the recent approval of CAR-T therapy, large-scale epidemiologic data are lacking. The present study aimed to characterize the epidemiology of hospitalizations, readmissions, and factors associated with all-cause 30-day readmission post CAR-T therapy. This retrospective cohort study used the Nationwide Readmissions Database from 2017 to 2019 to identify hospitalizations for CAR-T therapy administration. A descriptive analysis was performed after categorizing these hospitalizations as non-Hodgkin lymphoma, multiple myeloma, or leukemia. The readmission rate was calculated, and etiologies of readmission were identified. A Cox proportional hazards model was used to elucidate factors associated with 30-day readmission. We also estimated the healthcare utilization related to readmissions, including total hospital charges and length of stay. The 2,964 CAR-T therapy-related admissions included 2,176 with a diagnosis of non-Hodgkin lymphoma, 344 with multiple myeloma, and 445 with leukemia. The median length of stay was 15 days. Most CAR-T therapy recipients were male (63.4%), admitted to a teaching hospital (99.2%); 49.3% had private insurance, and 33.2% belonged to the highest-income communities. CAR-T therapy was administered mostly in privately owned (89.5%) large-sized hospitals (74.4%) in large metropolitan regions (91.4%). Median total hospital charges were highest for non-Hodgkin lymphoma, followed by leukemia and multiple myeloma ($945,645 versus $265,034 versus $184,194; P < .001). All-cause mortality during index hospitalization was highest for leukemia at 8.6%, followed by 3.6% for non-Hodgkin lymphoma and 1.4% for multiple myeloma (P < .001). The 30-day all-cause readmission rate was 23.6%, and the median time to readmission was 7 days. The readmission rate was highest for leukemia, followed by non-Hodgkin lymphoma and multiple myeloma (34.2% versus 22.8% versus 15.7%; P < .001). Readmission incurred an additional median total hospital charge of $64,561. During readmission, median length of stay was 5 days, and in-hospital mortality was 4.9%. Top etiologies for readmission were cancer or treatment-related (22%), sepsis or infection (18%), neurologic events (15%), neutropenia or pancytopenia (11%), and fever, hypotension, or hypoxia (8%). On multivariable analysis, non-Hodgkin lymphoma and leukemia (compared with multiple myeloma), transfer to a facility at discharge, chronic renal disease, cerebrovascular disease, and noninvasive ventilation were associated with higher odds of readmission. In contrast, admission to a teaching hospital predicted lower odds of readmission. Almost a quarter of CAR-T therapy recipients are readmitted within the first 30 days resulting in additional economic burden and substantial healthcare utilization.

Impact of Pre-transplant Induction Therapy on Outcomes of Patients Who Undergo Autologous Stem Cell Transplantation for Mantle Cell Lymphoma in First Complete Remission

Mantle cell lymphoma is a rare subtype of non-Hodgkin's lymphoma with poor prognosis and continue to be challenging to treat. The choice of first line induction regimen remains a topic of debate due paucity of clinical trials. We retrospectively evaluated 66 patients diagnosed with mantle cell lymphoma who achieved first complete response after induction chemotherapy followed by autologous stem cell transplant. Treatment groups were divided into low-intensity versus high-intensity regimens. Our data showed the intensity of induction regimen does not impact posttransplant outcomes of mantle cell lymphoma who underwent autologous stem cell transplant in first complete response.

Phase II Trial of Pembrolizumab and Anti-CD3 x Anti-HER2 Bispecific Antibody-Armed Activated T Cells in Metastatic Castration-Resistant Prostate Cancer

PURPOSE

A phase II study was conducted to evaluate the safety and efficacy of the combination of HER2 bispecific antibody (HER2Bi)-armed activated T cells (HER2 BAT) and programmed death 1 inhibitor, pembrolizumab.

PATIENTS AND METHODS

Patients with metastatic castration-resistant prostate cancer (mCRPC) with 0 to 1 performance status and normal liver, kidney, and marrow function, pre- or post-docetaxel chemotherapy were eligible. Primary endpoint was 6-month progression-free survival (PFS). Peripheral blood mononuclear cells were obtained by a single apheresis, shipped to University of Virginia, activated with OKT3 and expanded for 14 days in IL2, harvested, and armed with HER2Bi and cryopreserved. HER2 BATs were infused twice weekly for 4 weeks and pembrolizumab was administered every 21 days for a maximum duration of 6 months starting 1 to 3 weeks prior to HER2 BATs infusion.

RESULTS

Fourteen patients were enrolled with a median age of 69 (range 57-82 years) and median PSA of 143.4 (range 8.2-4210 ng/dL). Two patients had peritoneal metastases, 1 had lymph node (LN) only metastases and 11 had bone metastases of which 7 had bone and LN metastases. All were pretreated with androgen receptor axis targeted agents and 7 (50%) had prior docetaxel chemotherapy. The toxicities were grade1-2 infusion reactions with fever, chills, headaches, nausea and/or myalgias. Primary endpoint of 6 month PFS was achieved in 5 of 14 patients (38.5%; 95% confidence interval, 19.5%-76.5%). Median PFS was 5 months and median survival was 31.6 months.

CONCLUSIONS

The safety and promising efficacy makes this combination worthy of future investigation in mCRPC.

Severity of Cytokine Release Syndrome Influences Outcome After Axicabtagene Ciloleucel for Large B cell Lymphoma: Results from the US Lymphoma CAR-T Consortium

BACKGROUND

The majority of patients with large B-cell lymphoma treated with axicabtagene ciloleucel (axi-cel), an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, develop cytokine release syndrome (CRS). Whether the lack of development of CRS with axi-cel is associated with inferior lymphoma outcomes is unknown. Additionally, relationship between CRS grade and lymphoma outcome is not well established.

METHODS

The US Lymphoma CAR T Consortium includes seventeen US academic centers that contribute data independently of manufacturers. We analyzed the modified intent-to-treat population of 275 patients receiving axi-cel in two different ways: 1) Two group analysis comparing no CRS with any grade CRS; 2) Three group analysis comparing grade 0 CRS with grade 1 to 2 CRS, and grade 3-5 CRS.

RESULTS

In this large multi-center observational cohort of 275 patients receiving axi-cel, 9% (n = 24) did not develop CRS, 84% (n = 232) developed grade 1-2 CRS, and 7% (n = 19) developed grade 3 to 5 CRS. Patients without CRS, compared with those having any grade CRS, had similar overall response rates (ORR), lower complete response (CR) rates and inferior progression free survival (PFS) with no statistically significant difference in overall survival (OS). Patients experiencing grade 1 to 2 CRS had superior CR rate and PFS, as compared to those without CRS or with grade 3 to 5 CRS. Grade 3 to 5 CRS was associated with a worse OS.

CONCLUSION

Overall, durable responses were seen in patients that did not develop CRS, however grade 1 to 2 CRS was associated with better outcomes while those with grade 3 to 5 experienced the worse outcomes.

Health-Related Quality of Life in Young Adult Survivors of Hematopoietic Cell Transplantation

Young adults (YA), age 18 to 39 years, are at a stage of life that may make them more vulnerable than older adults to impairments in health-related quality of life (HRQOL) during and after hematopoietic cell transplantation (HCT). Health self-efficacy (HSE), the belief that one can implement strategies to produce a desired health outcome, has been associated with health outcomes in oncology research. Little is known about HRQOL or HSE in YA HCT survivors compared with older HCT survivors. Given the age-specific psychosocial challenges facing YA HCT recipients and research on non-transplant YA cancer survivors, we hypothesized that YA survivors would have worse post-HCT HRQOL compared with older adults, and that among YA HCT survivors, higher levels of HSE would be associated with higher levels of HRQOL and lower levels of cancer-related distress. This was a cross-sectional secondary analysis of 2 combined baseline datasets from multicenter studies of HCT survivors approached for participation in clinical trials of survivorship interventions. Participants from 20 transplantation centers in the United States were at 1 to 10 years post-HCT and age ≥18 years at the time of study enrollment, had no evidence of disease relapse/progression or subsequent malignancies, and could read English adequately to consent for and complete assessments. Medical record and patient-reported data were obtained for demographics and HCT-related clinical factors and complications (eg, total body irradiation, chronic graft-versus-host disease [cGVHD]). Participants completed surveys on HRQOL, including the Short-Form [SF]-12, HSE, and Cancer and Treatment Distress (CTXD), which includes 6 subscales and reports an overall mean score. On the SF-12, both the Mental Component Score (MCS) and Physical Component Score (PCS) were calculated. Two cohorts were compared: YAs (age 18 to 39 years at transplantation) and older adults (age ≥40 years at transplantation). Multiple linear regression analyses identified factors associated with HSE, PCS, MCS, and CTXD in YAs. In this analysis of 979 survivors, compared with the older adults, the YA participants had lower median mental health scores (SF-12 MCS: 48.40 versus 50.23; P = .04) and higher cancer-related distress (CTXD: .96 versus .85; P = .04), but better physical health (SF-12 PCS: 48.99 versus 47.18; P = .049). Greater overall cancer-related distress was driven by higher levels of uncertainty, financial concern, and medical demand subscales for YAs compared with older adults. Young adults also had lower HSE (2.93 versus 3.08; P = .0004). In a multivariate model, HSE was strongly associated with age group (P = .0005) after adjusting for multiple other transplantation-related factors. Among YAs, HSE was associated with the SF-12 MCS and PCS and the CTXD, and HSE remained significant after adjusting for other transplantation-related factors. Overall, the YA HCT survivors had lower mental health, increased cancer-related distress, and lower levels of HSE compared with the older adults. Although the direction of these effects cannot be determined with these data, the strong association between HSE and HRQOL among YAs suggests that targeting interventions to improve HSE may have broad impact on health outcomes.

Phase 1b/2 study of ciltacabtagene autoleucel, a BCMA-directed CAR-T cell therapy, in patients with relapsed/refractory multiple myeloma (CARTITUDE-1): Two years post-LPI

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Background: Ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T (CAR-T) cell therapy with 2 B-cell maturation antigen (BCMA)–targeting single-domain antibodies, led to early, deep, and durable responses in the phase 1b/2 CARTITUDE-1 study (NCT03548207) in heavily pretreated patients (pts) with relapsed/refractory multiple myeloma (RRMM). At ̃1-year (y) median follow-up (MFU), overall response rate (ORR) was 97%; 67% of pts achieved stringent complete response (sCR). 1-y progression-free survival (PFS) and overall survival (OS) rates were 77% and 89%, respectively (Berdeja 2021). Updated results 2-y post last patient in (LPI) will be presented (̃30-month total MFU). Here, we report CARTITUDE-1 results at 21.7-month MFU. Methods: Eligible pts with RRMM received ≥3 prior lines of therapy (LOT) or were refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD) and had received a PI, IMiD, and anti-CD38 antibody. Bridging therapy was permitted after apheresis. Pts received a single cilta-cel infusion (target dose 0.75×106 CAR+ viable T cells/kg) 5–7 days after lymphodepletion. Primary objectives were to evaluate cilta-cel safety and efficacy. Response was assessed per International Myeloma Working Group criteria by independent review committee and minimal residual disease (MRD) negativity at 10-5 by next-generation sequencing. Results: As of July 22, 2021, 97 pts (59% male; median age 61 y) received cilta-cel. Pts had a median of 6 (range 3–18) prior LOT; 84% were penta-drug exposed, 88% were triple-class refractory, 42% were penta-drug refractory, and 99% were refractory to last LOT. ORR was 97.9% (95% CI 92.7–99.7), 94.9% achieved very good partial response, and 82.5% achieved sCR. Median times to first response, best response, and ≥CR were 1.0, 2.6, and 2.9 months (m), respectively; median duration of response was not reached (NR). Of 61 pts evaluable for MRD, 92% were MRD negative (10-5), sustained for ≥6 m in 44% (27/61) and ≥12 m in 18% (11/61). 2-y PFS was 60.5% (95% CI 48.5–70.4). Median PFS and OS were NR. 2-y PFS rates in pts with sustained MRD negativity for ≥6 m and ≥12 m were 91% and 100%, respectively. There were no new safety signals or new events of CAR-T cell neurotoxicity, movement and neurocognitive treatment-emergent adverse events, or treatment-related deaths since 1-y MFU. 15 second primary malignancies were reported in 11 pts over ̃2-y MFU. Conclusions: At ̃2-y MFU, a single cilta-cel infusion led to deepening and durable responses in heavily pretreated pts with RRMM with a manageable safety profile. Follow-up is ongoing, and landmark 2-y post LPI data (̃8 m additional follow-up; ̃30 m total MFU) will be presented. Further investigations of cilta-cel are ongoing in earlier LOT and outpatient settings across the CARTITUDE program (NCT04133636, NCT04181827, NCT04923893). Clinical trial information: NCT03548207.

Process, resource and success factors associated with chimeric antigen receptor T-cell therapy for multiple myeloma

Background: Chimeric antigen receptor T-cell (CAR-T) therapy represents a new frontier in multiple myeloma. It is important to understand critical success factors (CSFs) that may optimize its use in this therapeutic area. Methods: We estimated the CAR-T process using time-driven activity-based costing. Information was obtained through interviews at four US oncology centers and with payer representatives, and through publicly available data. Results: The CAR-T process comprises 13 steps which take 177 days; it was estimated to include 46 professionals and ten care settings. CSFs included proactive collaboration, streamlined reimbursement and CAR-T administration in alternative settings when possible. Implementing CSFs may reduce episode time and costs by 14.4 and 13.2%, respectively. Conclusion: Our research provides a blueprint for improving efficiencies in CAR-T therapy, thereby increasing its sustainability for multiple myeloma.

Outcomes of Allogeneic Hematopoietic Cell Transplantation in T-cell Prolymphocytic Leukemia: A Contemporary Analysis from the Center for International Blood and Marrow Transplant Research

T cell prolymphocytic leukemia (T-PLL) is a rare, aggressive malignancy with limited treatment options and poor long-term survival. Previous studies of allogeneic hematopoietic cell transplantation (alloHCT) for T-PLL are limited by small numbers, and descriptions of patient and transplantation characteristics and outcomes after alloHCT are sparse. In this study, we evaluated outcomes of alloHCT in patients with T-PLL and attempted to identify predictors of post-transplantation relapse and survival. We conducted an analysis of data using the Center for International Blood and Marrow Transplant Research database on 266 patients with T-PLL who underwent alloHCT between 2008 and 2018. The 4-year rates of overall survival (OS), disease-free survival (DFS), relapse, and treatment-related mortality (TRM) were 30.0% (95% confidence interval [CI], 23.8% to 36.5%), 25.7% (95% CI, 20% to 32%), 41.9% (95% CI, 35.5% to 48.4%), and 32.4% (95% CI, 26.4% to 38.6%), respectively. In multivariable analyses, 3 variables were associated with inferior OS: receipt of a myeloablative conditioning (MAC) regimen (hazard ratio [HR], 2.18; P < .0001), age >60 years (HR, 1.61; P = .0053), and suboptimal performance status, defined by Karnofsky Performance Status (KPS) <90 (HR, 1.53; P = .0073). Receipt of an MAC regimen also was associated with increased TRM (HR, 3.31; P < .0001), an elevated cumulative incidence of grade II-IV acute graft-versus-host disease (HR, 2.94; P = .0011), and inferior DFS (HR, 1.86; P = .0004). Conditioning intensity was not associated with relapse; however, stable disease/progression was correlated with increased risk of relapse (HR, 2.13; P = .0072). Both in vivo T cell depletion (TCD) as part of conditioning and KPS <90 were associated with worse TRM and inferior DFS. Receipt of total body irradiation had no significant effect on OS, DFS, or TRM. Our data show that reduced-intensity conditioning without in vivo TCD (ie, without antithymocyte globulin or alemtuzumab) before alloHCT was associated with long-term DFS in patients with T-PLL who were age ≤60 years or who had a KPS >90 or chemosensitive disease.

Allogeneic hematopoietic stem cell transplantation in T-cell lymphoma: a Meta-Analysis

T-cell lymphoma (TCL) poses a therapeutic challenge. Allogeneic stem cell transplant (alloSCT) is frequently offered in primary refractory disease or failed autologous transplant. We systematically searched published articles on outcomes of alloSCT in TCL through PubMed and EMBASE database between January 2000 and October 2019. Among 651 identified studies, 22 (888 patients) were included. Forty percent patients had peripheral T-cell lymphoma not otherwise specified, 15% had angioimmunoblastic T-cell lymphoma, 21% had anaplastic large cell lymphoma, 5% had cutaneous T-cell lymphoma, and 19% had other histologic subtypes. Thirty-six percent patients had relapsed/refractory disease. Myeloablative conditioning regimens were used in 55% patients. At two-, three- and five-year post-transplant, overall survival was 57, 54 and 51%, respectively; progression-free survival was 45, 50 and 45%, respectively; non-relapse mortality was 9, 29 and 29%, respectively; relapse rate was 30, 28 and 29%, respectively. Our study shows that alloSCT provides durable remission in T cell lymphoma.

Improved post-ASCT survival of relapsed/refractory classical Hodgkin lymphoma patients in the era of novel agents

Utilization of novel agents such as brentuximab vedotin (BV) and check-point inhibitors (CI) has increased in patients with relapsed/refractory (r/r) classical Hodgkin Lymphoma (cHL). We conducted a retrospective study of 209 patients who had ASCT for r/r cHL at our institution and compared outcomes of those who had ASCT from 2010-2018 (cohort 2, n = 110) with those who had ASCT between 2000 and 2009 (cohort 1, n = 99). The median OS was 7.6 years for cohort 1 [HR 2.08; 95% CI 1.14-3.80; p = 0.017] and not reached for cohort 2; with 4-year improved OS difference of 15% (80% vs 65%) in cohort 2 vs cohort 1. The median PFS of cohort 1 was 30 months vs 39 months for cohort 2[HR 1.24; 95% CI 0.82-1.88; p = 0.3]. This study highlights improved OS of r/r cHL patients who have received ASCT in the novel agent era due to the exposure to agents such as BV and CIs.

Ciltacabtagene autoleucel, a B-cell maturation antigen-directed chimeric antigen receptor T-cell therapy in patients with relapsed or refractory multiple myeloma (CARTITUDE-1): a phase 1b/2 open-label study

BACKGROUND

CARTITUDE-1 aimed to assess the safety and clinical activity of ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T-cell therapy with two B-cell maturation antigen-targeting single-domain antibodies, in patients with relapsed or refractory multiple myeloma with poor prognosis.

METHODS

This single-arm, open-label, phase 1b/2 study done at 16 centres in the USA enrolled patients aged 18 years or older with a diagnosis of multiple myeloma and an Eastern Cooperative Oncology Group performance status score of 0 or 1, who received 3 or more previous lines of therapy or were double-refractory to a proteasome inhibitor and an immunomodulatory drug, and had received a proteasome inhibitor, immunomodulatory drug, and anti-CD38 antibody. A single cilta-cel infusion (target dose 0·75 × 10⁶ CAR-positive viable T cells per kg) was administered 5-7 days after start of lymphodepletion. The primary endpoints were safety and confirmation of the recommended phase 2 dose (phase 1b), and overall response rate (phase 2) in all patients who received treatment. Key secondary endpoints were duration of response and progression-free survival. This trial is registered with ClinicalTrials.gov, NCT03548207.

FINDINGS

Between July 16, 2018, and Oct 7, 2019, 113 patients were enrolled. 97 patients (29 in phase 1b and 68 in phase 2) received a cilta-cel infusion at the recommended phase 2 dose of 0·75 × 10⁶ CAR-positive viable T cells per kg. As of the Sept 1, 2020 clinical cutoff, median follow-up was 12·4 months (IQR 10·6-15·2). 97 patients with a median of six previous therapies received cilta-cel. Overall response rate was 97% (95% CI 91·2-99·4; 94 of 97 patients); 65 (67%) achieved stringent complete response; time to first response was 1 month (IQR 0·9-1·0). Responses deepened over time. Median duration of response was not reached (95% CI 15·9-not estimable), neither was progression-free survival (16·8-not estimable). The 12-month progression-free rate was 77% (95% CI 66·0-84·3) and overall survival rate was 89% (80·2-93·5). Haematological adverse events were common; grade 3-4 haematological adverse events were neutropenia (92 [95%] of 97 patients), anaemia (66 [68%]), leukopenia (59 [61%]), thrombocytopenia (58 [60%]), and lymphopenia (48 [50%]). Cytokine release syndrome occurred in 92 (95%) of 97 patients (4% were grade 3 or 4); with median time to onset of 7·0 days (IQR 5-8) and median duration of 4·0 days (IQR 3-6). Cytokine release syndrome resolved in all except one with grade 5 cytokine release syndrome and haemophagocytic lymphohistiocytosis. CAR T-cell neurotoxicity occurred in 20 (21%) patients (9% were grade 3 or 4). 14 deaths occurred in the study; six due to treatment-related adverse events, five due to progressive disease, and three due to treatment-unrelated adverse events.

INTERPRETATION

A single cilta-cel infusion at the target dose of 0·75 × 10⁶ CAR-positive viable T cells per kg led to early, deep, and durable responses in heavily pretreated patients with multiple myeloma with a manageable safety profile. The data from this study formed the basis for recent regulatory submissions.

FUNDING

Janssen Research & Development and Legend Biotech.

Prophylactic corticosteroid use in patients receiving axicabtagene ciloleucel for large B-cell lymphoma

ZUMA‐1 (NCT02348216) examined the safety and efficacy of axicabtagene ciloleucel (axi‐cel), an autologous CD19‐directed chimaeric antigen receptor (CAR)‐T cell therapy, in refractory large B‐cell lymphoma. To reduce treatment‐related toxicity, several exploratory safety management cohorts were added to ZUMA‐1. Specifically, cohort 6 investigated management of cytokine release syndrome (CRS) and neurologic events (NEs) with prophylactic corticosteroids and earlier corticosteroid and tocilizumab intervention. CRS and NE incidence and severity were primary end‐points. Following leukapheresis, patients could receive optional bridging therapy per investigator discretion. All patients received conditioning chemotherapy (days −5 through −3), 2 × 10⁶ CAR‐T cells/kg (day 0) and once‐daily oral dexamethasone [10 mg, day 0 (before axi‐cel) through day 2]. Forty patients received axi‐cel. CRS occurred in 80% of patients (all grade ≤2). Any grade and grade 3 or higher NEs occurred in 58% and 13% of patients respectively. Sixty‐eight per cent of patients did not experience CRS or NEs within 72 h of axi‐cel. With a median follow‐up of 8·9 months, objective and complete response rates were 95% and 80% respectively. Overall, prophylactic corticosteroids and earlier corticosteroid and/or tocilizumab intervention resulted in no grade 3 or higher CRS, a low rate of grade 3 or higher NEs and high response rates in this study population.

Post-transplant Cyclophosphamide Versus Thymoglobulin in HLA-Mismatched Unrelated Donor Transplant for Acute Myelogenous Leukemia and Myelodysplastic Syndrome

Limited information is available on the efficacy of post-transplantation cyclophosphamide (PTcy) or thymoglobulin for graft-versus-host disease (GVHD) prophylaxis in mismatched unrelated donor (MMUD) transplants. We retrospectively compared outcomes of 76 adult patients with acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS) who underwent 7/8 HLA-MMUD transplantation and received either PTcy (50 mg/kg on day 3 and 4) or thymoglobulin (total dose 4.5 mg/kg) for GVHD prophylaxis. In addition, tacrolimus and mycophenolate were used in both groups. Propensity score-based multivariable analyses (PSCA) were performed to adjust confounding effects of patient characteristics between both groups. Between January 2006 and June 2019, 25 patients received PTcy, and 51 received thymoglobulin. Median age of the population was 57 years, 78% of patients had AML, most common graft source was peripheral blood (96%), and 46% received myeloablative conditioning regimens. Median time to neutrophil (15 versus 11 days, P < .001) and platelet engraftment (21 versus 15 days, P = .002) was prolonged in the PTcy group. The cumulative incidence of grade III-IV acute GVHD at day 100 was similar (12% versus 19.6%, P = .38), whereas chronic GVHD at 1 year was lower with PTcy compared to thymoglobulin (16% versus 49%, P = .006). Using PSCA, no difference in survival, relapse, relapse-free survival, and GVHD-free relapse-free survival was seen between groups. However, thymoglobulin was associated with higher incidence of acute (hazard ratio [HR] = 2.63, P = .01) and chronic GVHD (HR = 4.43, P = .03), and non-relapse mortality (HR 3.38, P = .04) compared to PTcy. Our study demonstrated that PTcy resulted in significantly lower rates of acute and chronic GVHD and non-relapse mortality compared to thymoglobulin in 7/8 HLA-MMUD transplants for AML and MDS.

Phase II clinical trial using anti-CD3 × anti-HER2 bispecific antibody armed activated T cells (HER2 BATs) consolidation therapy for HER2 negative (0-2+) metastatic breast cancer

Background

Metastatic human epidermal growth receptor II (HER2) negative breast cancer remains incurable. Our phase I study showed that anti-CD3 × anti-HER2 bispecific antibody armed activated T cells (HER2 BATs) may be effective against HER2-tumors. This phase II trial evaluates the efficacy and immune responses of HER2 BATs given to patients with metastatic HER2-estrogen and/or progesterone receptor positive (HR+) and triple negative breast cancer (TNBC) as immune consolidation after chemotherapy. The primary objective of this study was to increase the traditional median time to progression after failure of first-line therapy of 2–4 months with the secondary endpoints of increasing overall survival (OS) and immune responses.

Methods

HER2- metastatic breast cancer (MBC) patients received 3 weekly infusions of HER2 BATs and a boost after 12 weeks.

Results

This phase II study included 24 HER2-HR+ and 8 TNBC patients who received a mean of 3.75 and 2.4 lines of prior chemotherapy, respectively. Eight of 32 evaluable patients were stable at 4 months after the first infusion. There were no dose limiting toxicities. Tumor markers decreased in 13 of 23 (56.5%) patients who had tumor markers. The median OS was 13.1 (95% CI 8.6 to 17.4), 15.2 (95% CI 8.6 to 19.8), and 12.3 (95% CI 2.1 to 17.8) months for the entire group, HER2-HR+, and TNBC patients, respectively. Median OS for patients with chemotherapy-sensitive and chemotherapy-resistant disease after chemotherapy was 14.6 (9.6–21.8) and 8.6 (3.3–17.3) months, respectively. There were statistically significant increases in interferon-γ immunospots, Th₁ cytokines, Th₂ cytokines, and chemokines after HER2 BATs infusions.

Conclusions

In heavily pretreated HER2-patients, immune consolidation with HER2 BATs after chemotherapy appears to increase the proportion of patients who were stable at 4 months and the median OS for both groups as well as increased adaptive and innate antitumor responses. Future studies combining HER2 BATs with checkpoint inhibitors or other immunomodulators may improve clinical outcomes.

Outcomes of Fludarabine, Melphalan and Total Body Irradiation as a Reduced Intensity Conditioning Regimen in Matched Donor Allogeneic Peripheral Blood Stem Cell Transplantation

Fludarabine 30 mg/m²/d × 5 and melphalan 140 mg/m² × 1 (Flu-Mel140) is a commonly used reduced-intensity conditioning regimen. We hypothesized that addition of 200cGy total body irradiation (TBI) to Flu-Mel140 may improve antitumor activity and transplant outcomes. Primary objectives was overall survival (OS) at 3 years. Secondary objectives were to assess the cumulative incidences of acute and chronic GVHD, relapse-free survival (RFS), relapse rate, and nonrelapse mortality (NRM). We retrospectively evaluated outcomes of patients receiving Flu-Mel140-TBI followed by HLA-matched donor allogeneic hematopoietic stem cell transplantation (alloSCT) using peripheral blood stem cells. Eighty-one patients (median age, 58 years) underwent alloSCT between January 2008 and December 2018. Thirty-one percent of patients had a prior transplant, 32% had high or very-high disease risk index, and the donor was unrelated in 70% of patients. Grade 3 to 4 regimen-related toxicities were mucositis (37%), cardiac toxicity (17%), and renal toxicity (10%). The cumulative incidence of grade III to IV acute GVHD at day +100 was 24.7% and chronic GVHD at 1 year was 51.3%. Median follow-up for survival was 6.1 years. At 3 years, OS was 39.81%, RFS was 31.47%, and relapse rate was 30.5%. One-year NRM was 29.9%. Patients undergoing first transplantation experienced improved OS compared with second or beyond (63.08% versus 42.31%, P = .02). After adjusting for disease subtypes, age (≤55 versus 55), comorbidity index (CI), number of transplant and GVHD prophylaxis, multivariable analysis did not demonstrate any survival difference among disease subtypes. High CI (≥3) was predictive of adverse OS and NRM, whereas older age (>55 years) was associated with high NRM. Our study shows that Flu-Mel140-TBI seems feasible and provides durable disease control. Addition of TBI did not appear to improve outcomes compared to previously published reports of Flu-Mel140. Considerable NRM could result from the inclusion of patients with older age and prior transplants.

Grade 3-4 cytokine release syndrome is associated with poor survival in haploidentical peripheral blood stem cell transplantation

The information on the impact of cytokine release syndrome (CRS) on haploidentical donor peripheral blood stem cell transplant (haploPBSCT) outcomes is limited. We retrospectively evaluated 98 patients who underwent haploPBSCT between June 2012 and June 2019 for the onset and severity of CRS per the ASTCT guidelines. The incidence of CRS was 93% (91/98). Outcomes were compared between grade 1-2 and 3-4 CRS. Eighty-one patients developed grade 1-2 CRS (89%) and 10 (11%) developed grade 3-4 CRS. Compared to grade 1-2 CRS, grade 3-4 CRS experienced adverse survival (73.7% vs. 30%, p<.001), inferior relapse-free survival (64.0% vs. 20%, p<.001), and higher non-relapse mortality (NRM) (16.4% vs. 60%, p<.001) at 1-year. Propensity score-based multivariable analyses revealed worse survival (HR 2.71, p=.04), and higher NRM (SHR 4.51, p=.006) with grade 3-4 CRS. Our study shows that grade 3-4 CRS was adversely associated with survival. Therefore, early identification and preventive strategies are warranted.

Comparison of myeloablative and reduced intensity conditioning unrelated donor allogeneic peripheral blood stem cell transplant outcomes for AML using thymoglobulin for GVHD prophylaxis

A head-to-head comparison of outcomes of unrelated donor allogeneic peripheral blood stem cell transplantation for AML between reduced intensity conditioning (RIC) and myeloablative conditioning (MAC) regimens using thymoglobulin for GVHD prophylaxis is limited. We evaluated outcomes of 122 AML patients who received either busulfan (Bu)/fludarabine (Flu)/low-dose total body irradiation (TBI) as RIC (n = 64, 52%) or Bu/Flu as MAC (n = 58, 48%), and thymoglobulin 4.5 mg/kg total dose between day - 3 to - 1 for GVHD prophylaxis. Grades III-IV acute GVHD (aGVHD) was lower with Bu/Flu/TBI compared with Bu/Flu (6.2% vs 26.1%, p = 0.009). At 1 year, Bu/Flu/TBI was associated with similar chronic GVHD (41.2% vs 44.8%, p = 0.75), OS (61.9% vs 56.9%, p = 0.69), relapse rate (29.9% vs 20.7%, p = 0.24), relapse-free survival (52.8% vs 50%, p = 0.80), non-relapse mortality (17.4% vs 29.3%, p = 0.41), and GVHD-free relapse-free survival (24.2% vs 27.5%, p = 0.80) compared with Bu/Flu. Multivariable analysis did not reveal any difference in outcomes between both regimens. In summary, thymoglobulin at 4.5 mg/kg did not have any adverse impact on survival when used with RIC regimen. Both Bu/Flu/TBI and Bu/Flu conditioning regimens yielded similar survival.

Midostaurin after allogeneic stem cell transplant in patients with FLT3-internal tandem duplication-positive acute myeloid leukemia

We evaluated standard-of-care (SOC) treatment with or without midostaurin to prevent relapse following allogeneic hematopoietic stem cell transplant (alloHSCT) in patients with acute myeloid leukemia (AML) harboring internal tandem duplication (ITD) in FLT3. Adults (aged 18–70 years) who received alloHSCT in first complete remission, had achieved hematologic recovery, and were transfusion independent were randomized to receive SOC with or without midostaurin (50 mg twice daily) continuously in twelve 4-week cycles. The primary endpoint was relapse-free survival (RFS) 18 months post-alloHSCT. Sixty patients were randomized (30/arm); 30 completed all 12 cycles (midostaurin + SOC, n = 16; SOC, n = 14). The estimated 18-month RFS (95% CI) was 89% (69–96%) in the midostaurin arm and 76% (54–88%) in the SOC arm (hazard ratio, 0.46 [95% CI, 0.12–1.86]; P = 0.27); estimated relapse rates were 11% and 24%, respectively. Inhibition of FLT3 phosphorylation to <70% of baseline (achieved by 50% of midostaurin-treated patients) was associated with improved RFS. The most common serious adverse events were diarrhea, nausea, and vomiting. Rates of graft-vs-host disease were similar between both arms (midostaurin + SOC, 70%; SOC, 73%). The addition of midostaurin maintenance therapy following alloHSCT may provide clinical benefit in some patients with FLT3-ITD AML. (ClinicalTrials.gov identifier: NCT01883362).

Comparison of myeloablative and reduced intensity conditioning regimens in haploidentical peripheral blood stem cell transplantation

Limited information is available on the impact of intensity of conditioning regimens in haploidentical peripheral blood stem cell transplant (haploPBSCT) with post-transplant cyclophosphamide (PTcy). We retrospectively compared outcomes of haplo-PBSCT between myeloablative (MAC) (n = 24) and reduced intensity conditioning (RIC) regimens (n = 65). Propensity score-based multivariable analyses were performed to adjust confounding effects of baseline characteristics between both groups. Eighty-nine patients underwent haplo-PBSCT between January 2012 and June 2019. For MAC and RIC, the cumulative incidences of grade III--IV acute GVHD were 4.2% and 3.1%, respectively (p = 0.92), and chronic GVHD were 18.9% and 36.5%, respectively (p = 0.08). Median follow-up for overall survival (OS) after MAC and RIC was 1.86 and 2.2 years, respectively. For MAC and RIC, one-year OS was 68.8% and 67.4%, respectively (p = 0.85); one-year relapse rate was 22.4% and 18.3%, respectively (p = 0.74); one-year relapse-free survival (RFS) was 56% and 59.7%, respectively (p = 0.87); and one-year non-relapse mortality (NRM) was 22% and 21.9%, respectively (p = 0.58). Using propensity score-based multivariable analyses, no difference in OS (HR 0.72, p = 0.51), relapse (SHR 0.63, p = 0.42), RFS (HR 0.74, p = 0.49) and NRM (SHR 1.11, p = 0.87) was noted between RIC and MAC. Our study shows no difference in outcomes between MAC and RIC regimens in haplo-PBSCT.

G-CSF use post peripheral blood stem cell transplant is associated with faster neutrophil engraftment, shorter hospital stay and increased incidence of chronic GVHD

The use of G-CSF post allogeneic transplant has become a common practice to accelerate neutrophil engraftment. There is some controversy in its use. To further evaluate the effectiveness, we compared outcomes in patients who underwent PBSCT, either with or without the planned use of G-CSF post SCT. Among consecutive 162 patients from October 2012 to October 2014, 65 patients received G-CSF post-PBSCT, and 97 did not. More patients in G-CSF group received MAC (78% vs. 55%). Patients who received G-CSF had earlier neutrophil engraftment (median days 11 vs. 14) and shorter post-transplant hospital stay (median days 16 vs. 20, p = 0.001). G-CSF use was associated with a higher rate of extensive chronic GVHD (44.3% vs.61.5%, p = 0.027). G-CSF cost the equivalent of 0.25 hospital days but shortened the initial transplant admission by 4 days. Early cost-benefit may be later offset by the economic burden of chronic GVHD and associated complications.

Standard-of-Care Axicabtagene Ciloleucel for Relapsed or Refractory Large B-Cell Lymphoma: Results From the US Lymphoma CAR T Consortium

PURPOSE

Axicabtagene ciloleucel (axi-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for relapsed/refractory large B-cell lymphoma (LBCL) on the basis of the single-arm phase II ZUMA-1 trial, which showed best overall and complete response rates in infused patients of 83% and 58%, respectively. We report clinical outcomes with axi-cel in the standard-of-care (SOC) setting for the approved indication.

PATIENTS AND METHODS

Data were collected retrospectively from all patients with relapsed/refractory LBCL who underwent leukapheresis as of September 30, 2018, at 17 US institutions with the intent to receive SOC axi-cel. Toxicities were graded and managed according to each institution's guidelines. Responses were assessed as per Lugano 2014 classification.

RESULTS

Of 298 patients who underwent leukapheresis, 275 (92%) received axi-cel therapy. Compared with the registrational ZUMA-1 trial, 129 patients (43%) in this SOC study would not have met ZUMA-1 eligibility criteria because of comorbidities at the time of leukapheresis. Among the axi-cel-treated patients, grade ≥ 3 cytokine release syndrome and neurotoxicity occurred in 7% and 31%, respectively. Nonrelapse mortality was 4.4%. Best overall and complete response rates in infused patients were 82% (95% CI, 77% to 86%) and 64% (95% CI, 58% to 69%), respectively. At a median follow-up of 12.9 months from the time of CAR T-cell infusion, median progression-free survival was 8.3 months (95% CI, 6.0 to15.1 months), and median overall survival was not reached. Patients with poor Eastern Cooperative Oncology Group performance status of 2-4 and elevated lactate dehydrogenase had shorter progression-free and overall survival on univariable and multivariable analysis.

CONCLUSION

The safety and efficacy of axi-cel in the SOC setting in patients with relapsed/refractory LBCL was comparable to the registrational ZUMA-1 trial.

Clinical and immune responses to anti-CD3 x anti-EGFR bispecific antibody armed activated T cells (EGFR BATs) in pancreatic cancer patients

Purpose

This was a phase I/II adoptive T cell trial in 7 locally advanced and metastatic pancreatic cancer patients using 3–8 infusions of anti-CD3 x anti-EGFR bispecific antibody armed activated T cells (BATs) to determine safety, the maximum tolerated dose (MTD), immune responses, time to progression (TTP), and overall survival (OS). Study Design: T cells obtained by apheresis were expanded and armed with EGFRBi, cryopreserved for infusions. In a phase I dose escalation, five patients received three weekly infusions of 10–40 × 10⁹ BATs/infusion followed by a booster infusion 3 months later, and 2 patients received 8 infusions twice weekly for 4 weeks in a phase II. The trials were registered at http://www.clinicaltrials.gov, NCT01420874 and NCT02620865. Results: There were no dose-limiting toxicities (DLTs), and the targeted dose of 80 × 10⁹ BATs was met. The median TTP is 7 months, and the median OS is 31 months. Two patients had stable disease for 6.5 and 25+ months, and two patients developed complete responses (CRs) after restarting chemotherapy. Infusions of BATs induced anti-pancreatic cancer cytotoxicity, innate immune responses, cytokine responses (IL-12, IP-10), and shifts in CD4 and CD8 Vβ repertoire with enhanced cytoplasmic IFN-γ staining in the Vβ repertoire of the CD8 subset that suggest specific clonal TCR responses. Conclusions: Infusions of BATs are safe, induce endogenous adaptive anti-tumor responses, and may have a potential to improve overall survival.

Grade III-IV cytokine release syndrome is associated with inferior survival in patients undergoing haploidentical donor stem cell transplants

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Background: Haploidentical transplant (HIDT) with post-transplant cyclophosphamide (pCY) is being increasingly used because of the universal availability of donor and rapid graft acquisition time. Cytokine release syndrome (CRS) is one of the commonly occurring complications in this population. The information on the impact of CRS on the post-HIDT outcomes is limited. Methods: We retrospectively evaluated 91 patients who underwent HIDT between June 2012 and June 2019 for the onset and severity of CRS. CRS was graded per ASTCT guidelines. The primary objective was to compare RFS (relapse-free survival), NRM (non-relapse mortality), OS (overall survival) and GVHD in patients with no CRS, CRS grade 1-2 and 3-4. Results: All received peripheral blood stem cells and pCY/tacrolimus/mycophenolate as GVHD prophylaxis. Fifty-six (62%) received reduced intensity and 35 (38%) received full intensity conditioning regimen. Ten (10.9%) had no CRS, 74 (81.3%) developed grade 1-2 CRS and seven (7.7%) experienced grade 3-4 CRS. Median time to onset of CRS was one day post-transplant. The most common symptoms were fever (87%), fatigue (30%), nausea/vomiting (24%), rigors (24%), diarrhea (20%) and rash (11%). Fifteen (20%) with grade 1-2 and six (85%) with grade 3-4 CRS received tocilizumab. Day +100 cumulative incidence of grade III-IV acute GVHD for no CRS, grade 1-2 and grade 3-4 CRS was 0%, 2.7%, and 14.3%, respectively (P = 0.36). One-year cumulative incidence of chronic GVHD for no CRS, grade 1-2 and grade 3-4 CRS was 30%, 31.9% and 14.3%, respectively (P = 0.70). One-year NRM for no CRS, grade 1-2 and grade 3-4 CRS was 30%, 16.5%, and 57.1%, respectively (P = 0.002). One-year RFS for no CRS, grade 1-2 and grade 3-4 CRS was 48%, 63.4% and 28.6%, respectively (p = 0.03). OS at 1-year for no CRS, grade 1-2 and grade 3-4 CRS was 60%, 73.9%, and 28.6%, respectively (P = 0.008). Multivariable analysis revealed that grade 3-4 CRS was associated with significantly higher NRM (HR 5.54, P = 0.002), worse RFS (HR 3.41, P = 0.011) and worse OS (HR 4.91, P = 0.001). Conditioning regimen, degree of HLA match and disease risk index did not affect post-transplant outcomes and were not predictors for developing CRS. Conclusions: Our study showed that grade 3-4 CRS was associated with inferior post-transplant outcomes. However, no impact on acute or chronic GVHD was noted. Therefore, early recognition and prompt management of CRS may help improve outcomes.

Very long term follow-up of high dose chemotherapy followed by autologous stem cell transplantation in high risk locally advanced triple negative breast cancer

e13094

Background: The role of High Dose Chemotherapy (HDC) with Autologous Stem Cell Transplantation (ASCT) in treatment of high risk locally advanced breast cancer remains unclear. This modality stopped being used for breast cancer treatment when trials in early 2000s reported Disease Free Survival (DFS) benefit but no Overall survival (OS) benefit. However, subgroup analyses of these studies reported OS benefit in young and Triple Negative Breast Cancer (TNBC). We report very long-term outcomes of high risk locally advanced TNBC treated with HDC-ASCT at our institution between 1995 and 2001. Methods: We reviewed our BMT database for women with stage IIB or III TNBC treated with HDC-ASCT. We excluded women with hormone positive, Her2/Neu positive/Unknown and metastatic disease prior to transplant per updated AJCC 7th edition. The majority of patients underwent surgery followed by adjuvant Anthracycline and Taxane based induction chemotherapy followed by HDC-ASCT for consolidation. The HDC regimen consisted of Carmustine 600 mg/m2, Cyclophosphamide 5.6gm/ m2 and Cisplatin 165mg/ m2 (STAMP 1 regimen). Four patients received induction regimen as neoadjuvant and HDC-ASCT as adjuvant treatment per the same protocol. All patients received loco-regional radiation after ASCT. Results: 29 patients had locally advanced TNBC treated with HDC-ASCT. Median age at diagnosis was 43 years (IQR 40-51). 28 had at least 4 positive lymph nodes. Median time from diagnosis to ASCT was 5 months. Median overall survival was 17 years (95% CI, 3-19 years), and median DFS was 14 years (95% CI, 1-19). There was no treatment related mortality (TRM) at 30- and 100-days post ASCT. 12 patients (41%) were alive at median of 16 years (95% CI, 12-19) post ASCT. Conclusions: This single institution study of locally advanced high risk TNBC patients who received HDC-ASCT as part of treatment demonstrates a high long term OS exceeded historical controls. This supports a potential role for HDC-ASCT in this cohort of high risk TNBC. Considering the low TRM associated with this approach, prospective evaluation of this strategy is warranted.

Toxicities after high dose post-transplant cyclophosphamide in haploidentical donor transplants: Risk factors and impact on survival

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Background: Post-transplant cyclophosphamide (pCY) when given at 50mg/kg on day +3 and +4 in haploidentical donor transplants (HIDT) leads to considerable morbidity. Information on its toxicity and impact on outcomes is limited. Methods: We analyzed 91 patients (pt) undergoing HIDT with pCY to estimate incidence and risk factors of mucositis, hemorrhagic cystitis, renal and cardiac toxicities during the first 6 months after transplant and its impact on overall survival (OS). We compared these complications with 91 pt who were matched for age, disease, disease status at transplant, conditioning regimen and received 8/8 HLA-matched transplants without pCY (non-pCY cohort). Results: Fourteen pt (15%) in non-pCY and 28 (31%) in pCY experienced hypoxia requiring oxygen (p = 0.03). Ten pt (11%) in non-pCY and 21 (23%) in pCY developed clinically significant hypotension (p = 0.05). Day +100 cumulative incidence rate (CIR) of mucositis was 59.3% for non-pCY and 84.6% for pCY (p < 0.001). Seven pt (13%) in non-pCY cohort and 39 (51%) in pCY developed grade 3-4 mucositis (p < 0.001). Two pt (2%) in non-pCY and 22 (24%) in pCY developed gross hematuria (p = 0.05). Day +180 CIR of hemorrhagic cystitis was 13.2% for non-pCY and 29.7% for pCY (p = 0.005). Hemorrhagic cystitis did not have an adverse impact on non-relapse mortality (NRM) and OS. Day +180 CIR of renal toxicities was 17.6% for non-pCY and 28.6% for pCY (p = 0.10). The CIR of cardiac toxicities at day +180 was 9.9% for non-pCY and 14.3% for pCY (p = 0.34). Congestive heart failure (59%) and atrial fibrillation (36%) were the most common cardio-toxicities. One-year NRM was 38.5% in pt developing cardio-toxicity in the pCY cohort compared to no cardio-toxicity (15.3% in non-pCY and 18.3% in pCY, p = 0.004). OS was inferior in pt with cardio-toxicity in non-pCY (HR 5.49, p < 0.001) and pCY (HR 2.3, p = 0.03) compared to pt without cardio-toxicity. In multivariable analysis, pCY was associated with an increased risk of mucositis (HR 1.48, p = 0.03), and hemorrhagic cystitis (HR 2.67, p = 0.004). The number of infused CD34 cells was associated an increased risk of cardiac toxicity (HR 1.13, p = 0.005). pCY was not associated with higher cardiac complications, and no impact of the number of infused CD34 cells, conditioning regimen and prior transplant was observed on hemorrhagic cystitis and mucositis. Conclusions: pCY was associated with significant morbidity compared to HLA-matched non-pCY cohort. Although cardio-toxicities were similar between both groups, it was associated with worse survival.

Lenalidomide maintenance after second autologous stem cell transplant improves overall survival in multiple myeloma

Maintenance therapy after first autologous transplant (autoSCT) improves progression-free survival (PFS) and overall survival (OS) in multiple myeloma (MM). However, efficacy of maintenance therapy after second autoSCT is unknown. We retrospectively evaluated outcomes of 111 adult MM patients who underwent second autoSCT between January 2000 and December 2018. Lenalidomide up to 15 mg daily or subcutaneous bortezomib 1.3 mg/m² every 2 weeks was considered maintenance therapy. Outcomes were compared among three groups: no-maintenance (n = 73), lenalidomide (n = 23), and bortezomib maintenance (n = 15). At a median follow-up of 58 months from second autoSCT for survival, 3-year PFS and OS for no-maintenance, lenalidomide, and bortezomib maintenance were 11.2%, 29.9%, and 0%, respectively; and 58.5%, 83.3%, and 67.5% respectively. Lenalidomide maintenance was associated with improved PFS (HR 0.46, p = 0.009) and OS (HR 0.25, p = 0.009) compared to no-maintenance. Lenalidomide maintenance therapy after second autoSCT appears to prolong PFS and OS.