You are here

  • Home
  • Archive
  • Volume 12, Issue 4
  • Combinational therapy of CAR T-cell and HDT/ASCT demonstrates impressive clinical efficacy and improved CAR T-cell behavior in relapsed/refractory large B-cell lymphoma

Article Text

Article menu
Clinical/translational cancer immunotherapy
Original research
Combinational therapy of CAR T-cell and HDT/ASCT demonstrates impressive clinical efficacy and improved CAR T-cell behavior in relapsed/refractory large B-cell lymphoma
  1. Wei Liu1,2,3,
  2. Wei Liu1,
  3. Hesong Zou1,
  4. Lianting Chen1,
  5. Wenyang Huang1,2,
  6. Rui Lv1,2,
  7. Yan Xu1,2,
  8. Huimin Liu1,2,
  9. Yin Shi1,2,
  10. Kefei Wang1,
  11. Yi Wang1,2,
  12. Wenjie Xiong1,2,
  13. Shuhui Deng1,2,
  14. Shuhua Yi1,2,
  15. Weiwei Sui1,2,
  16. Guangxin Peng1,2,
  17. Yueshen Ma1,2,
  18. Huijun Wang1,2,
  19. Lulu Lv4,
  20. Jianxiang Wang1,2,3,
  21. Jun Wei1,2,
  22. Lugui Qiu1,2,
  23. Wenting Zheng1,2 and
  24. Dehui Zou1,2,3
  1. 1 State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
  2. 2 Tianjin Institutes of Health Science, Tianjin, China
  3. 3 Tianjin Key Laboratory of Cell Therapy for Blood Diseases, Tianjin, China
  4. 4 Juventas Cell Therapy Ltd, Tianjin, China
  1. Correspondence to Mrs Wenting Zheng; zhengwenting{at}ihcams.ac.cn; Dr Dehui Zou; zoudehui{at}ihcams.ac.cn

Abstract

Background Approximately two-thirds of patients with relapsed or refractory large B-cell lymphoma (R/R LBCL) do not respond to or relapse after anti-CD19 chimeric antigen receptor T (CAR T)-cell therapy, leading to poor outcomes. Previous studies have suggested that intensified lymphodepletion and hematological stem cell infusion can promote adoptively transferred T-cell expansion, enhancing antitumor effects. Therefore, we conducted a phase I/II clinical trial in which CNCT19 (an anti-CD19 CAR T-cell) was administered after myeloablative high-dose chemotherapy and autologous stem cell transplantation (HDT/ASCT) in patients with R/R LBCL.

Methods Transplant-eligible patients with LBCL who were refractory to first-line immunochemotherapy or experiencing R/R status after salvage chemotherapy were enrolled. The study aimed to evaluate the safety and efficacy of this combinational therapy. Additionally, frozen peripheral blood mononuclear cell samples from this trial and CNCT19 monotherapy studies for R/R LBCL were used to evaluate the impact of the combination therapy on the in vivo behavior of CNCT19 cells.

Results A total of 25 patients with R/R LBCL were enrolled in this study. The overall response and complete response rates were 92.0% and 72.0%, respectively. The 2-year progression-free survival rate was 62.3%, and the overall survival was 68.5% after a median follow-up of 27.0 months. No unexpected toxicities were observed. All cases of cytokine release syndrome were of low grade. Two cases (8%) experienced grade 3 or higher CAR T-cell-related encephalopathy syndrome. The comparison of CNCT19 in vivo behavior showed that patients in the combinational therapy group exhibited enhanced in vivo expansion of CNCT19 cells and reduced long-term exhaustion formation, as opposed to those receiving CNCT19 monotherapy.

Conclusions The combinational therapy of HDT/ASCT and CNCT19 demonstrates impressive efficacy, improved CNCT19 behavior, and a favorable safety profile.

Trial registration numbers ChiCTR1900025419 and NCT04690192.

  • Lymphoma
  • Chimeric antigen receptor - CAR
  • Transplant
  • Relapse
  • B cell

Data availability statement

Data are available on reasonable request. The deidentified participant data of this study are available from the corresponding author (email: zoudehui@ihcams.ac.cn) on reasonable request. Reuse of the data requires permission from all corresponding authors.

http://creativecommons.org/licenses/by-nc/4.0/

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See http://creativecommons.org/licenses/by-nc/4.0/.

https://doi.org/10.1136/jitc-2024-008857

Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    WHAT IS ALREADY KNOWN ON THIS TOPIC

    • CD19 CAR T-cell is a promising therapy for patients with relapsed/refractory large B-cell lymphoma (R/R LBCL). However, only one-third of patients achieve durable disease remission. There is an urgent need for methods to improve the efficacy of CAR T-cell therapy.

    WHAT THIS STUDY ADDS

    • In this study, we combined high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HDT/ASCT) with CAR T-cell therapy. The combinational therapy demonstrated impressive efficacy and favorable safety in patients with R/R LBCL. Additionally, this combined approach was observed to enhance the in vivo expansion and reduce the exhaustion formation of CAR T cells.

    HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

    • The combination of HDT/ASCT with CAR T-cell therapy might emerge as a novel strategy for the treatment of transplantation-eligible R/R LBCL.

    Introduction

    Although approximately 60% of patients with large B-cell lymphoma (LBCL) achieve long-term remission after first-line immunochemotherapy, patients who are refractory to first-line therapy or relapse/refractory (R/R) to salvage therapy have remarkably poor outcomes.1–5 CD19-directed chimeric antigen receptor T (CAR T) cells represent a breakthrough for R/R LBCL.6–8 However, approximately 60%–70% of patients fail to respond to or relapse after CAR T-cell therapy.9–11 Considering the dismal outcomes observed in individuals whose diseases progressed after CAR T-cell treatment,12–14 there is an unmet clinical need for strategies to improve the efficacy of CAR T-cell therapy.

    Lymphodepleting therapy, administered prior to CAR T-cell infusion, plays a pivotal role in eliminating immunosuppressive cells and enhancing expansion and persistence of CAR T cells.15 16 High-intensity lymphodepletion has been associated with a higher likelihood of a favorable cytokine profile, potentially resulting in longer progression-free survival (PFS) in patients with diffuse LBCL (DLBCL).17 Another factor affecting CAR T-cell therapy efficacy is the tumor burden. High baseline metabolic tumor volume is associated with a poorer PFS and overall survival (OS) in patients with DLBCL undergoing axicabtagene ciloleucel (axi-cel) treatment.18 In addition, hematopoietic stem cell infusion has been demonstrated to enhance antitumor T-cell expansion and function in a mouse model.19 Thus, we hypothesized that high-dose chemotherapy and autologous stem cell transplantation (HDT/ASCT) administered prior to CAR T-cell infusion would decrease tumor burden, diminish immunosuppressive microenvironment, enhance CAR T-cell function, and ultimately improve efficacy.

    CNCT19 is an autologous second-generation anti-CD19 CAR T-cell developed by the Institute of Hematology & Blood Diseases Hospital20 21 and has recently received approval from the National Medical Products Administration for the treatment of adult R/R B-cell acute lymphoblastic leukemia in China. It comprised a single-chain variable fragment derived from a new HI19α hybridoma clone, with 4-1BB/CD3-ζ as a costimulatory domain.20 The CNCT19 pilot clinical trial targeting 16 patients with R/R LBCL at our institution demonstrated favorable safety as all cases of cytokine release syndrome (CRS) were grade 1, and only one patient experienced CAR T-cell-related encephalopathy syndrome (CRES).22 To investigate the safety and efficacy of CAR T-cell administration following HDT/ASCT, we conducted a single-arm, single-center phase I/II clinical study at our institute that involved the concurrent administration of HDT/ASCT and CNCT19 treatment for patients with R/R LBCL. Additionally, to explore the cellular mechanism, patients who had frozen peripheral blood samples and received CNCT19 monotherapy in other clinical trials were included in the exploratory analysis. We compared the patients’ baseline characteristics and examined the differences in the in vivo behavior of circulating CNCT19 cells (CNCT19s) postinfusion between the combinational treatment group and the CNCT19 monotherapy group.

    Subjects and methods

    Trial design

    In this phase I/II clinical trial, transplantation-eligible patients with LBCL who were refractory to a first-line rituximab-containing anthracycline-based chemotherapy regimen and/or who had an R/R status after at least two cycles of salvage chemotherapy were included. (Detailed inclusion and exclusion criteria are listed in the Methods section of online supplemental appendix). After written informed consent was obtained, patients underwent two separate apheresis procedures: granulocyte colony-stimulating factor-primed hematopoietic progenitor cell collection for HDT/ASCT and peripheral blood mononuclear cell (PBMC) apheresis for CNCT19 manufacturing. The PBMC apheresis product was transported to Juventas Cell Therapy Ltd. for CNCT19 central manufacturing. At the discretion of the treating clinician, patients could undergo salvage or bridging therapies with the aim of achieving optimal disease control before the initiation of HDT/ASCT and CNCT19 treatment. The conditioning regimen of GBC/M (gemcitabine 600 mg/m2/hour, infused for 3 hours with loading bolus of 75 mg/m2, day −7 to –3, busulfan 105 mg/m2 day −7 until −5, cyclophosphamide 45 mg/kg or melphalan 60 mg/m2, day −3 to –2)23 24 was administered on availability of the CNCT19 product, and the patient’s eligibility for the study therapy was confirmed. Autologous stem cells were infused on day 0, and CNCT19s were infused on day +3 (±1 day) (figure 1A).

    Supplemental material

    Figure 1
    Figure 1

    Treatment schema (A) and patient flow (B). *CNCT19 is an anti-CD19 chimeric antigen receptor T cells. HDT/ASCT, high dose chemotherapy and autologous stem cell transplantation; HSC, hematopoietic stem cell.

    Safety assessments

    CRS and CRES were graded according to the CAR T-cell-therapy-associated TOXicity Working Group criteria.25 Hematological and non-hematological toxicities were assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events, V.4.03. The time of hematological recovery was also observed after stem cell infusion. Neutrophil recovery was defined as the first of 3 successive days with an absolute neutrophil count of ≥500/µL after post-HCT nadir. Platelet recovery was defined as the first of seven consecutive days with a platelet count of ≥20×109/L in the absence of platelet transfusion.

    Response and cellular kinetic assessment

    CT and fluorodeoxyglucose positron emission tomography/CT (PET/CT) scans were used for the response assessments. CT scan was performed at screening stage, preconditioning chemotherapy, month 1, month 2, month 3, and every 3 months thereafter for the first year, every 6 months for the second year, and annually thereafter up to 5 years. PET/CT scan was performed in all patients at screening stage, month 3 and time of suspected relapse, and Deauville score of 4 or 5 was considered as positive. The study therapy efficacy was assessed by the investigators according to the Lugano criteria (2014).26 27 For patients with bone marrow involvement at baseline, bone marrow reassessment including immunohistochemistry was conducted to confirm a complete response (CR). The CNCT19 expansion was quantified via flow cytometry at days 4, 7, 11, 14, 21, 28 (calculated from the CNCT19 infusion date), and days of follow-up thereafter.

    Study endpoints

    The primary endpoint of the study was the incidence of adverse events and the best overall response rate (ORR, defined as the proportion of patients who achieved a best response of CR or partial response (PR)). Secondary endpoints included the CR rate, duration of response (DOR), disease-free survival (DFS), PFS, and OS. DOR was defined as the time from first CR or PR to disease progression or death from any causes. DFS was defined as the time from first CR to disease progression or death from any cause. PFS was defined as the time from CNCT19 infusion to disease progression or death from any cause. OS was defined as the time from CNCT19 infusion to the date of death from any cause.

    Characteristics of circulating CNCT19 postinfusion between the combinational therapy and CNCT19 monotherapy

    PBMC samples collected at weeks 1, 2, 4, and 8 after CNCT19 infusion were resuscitated and assessed using flow cytometry. Patients with available frozen samples from this trial and from three other clinical trials (NCT03029338, NCT04232826, and NCT04586478) in which patients with R/R LBCL received CNCT19 monotherapy were included in this exploratory analysis. The expansion capacity, differentiation and exhaustion status of circulating CNCT19 postinfusion were examined by measuring the percentage and amount of CNCT19s and Ki67, CCR7, CD45RO, PD-1, and TIGIT expression on CNCT19s through flow cytometry. The cell number kinetics and Ki67, CCR7, CD45RO expression were assessed at 1, 2, and 4 weeks after infusion. The upregulation of inhibitory molecules (PD-1, TIGIT, LAG-3, etc) usually indicated early-stage CD8+ T-cell activation and CD8+ T-cell exhaustion after long-term continuous antigen priming.28–30 Thus, PD-1 and TIGIT expression on CD8+ CNCT19s was assessed at 1–2 months after infusion. A detailed information of cell staining and flow cytometry is presented in online supplemental methods section.

    Clinical relevance of exhaustion status in CNCT19s

    The correlation between the exhaustion status of CNCT19s and clinical outcomes was further explored. According to the long-term responses of patients involved in the exploratory analysis, we categorized them into three groups. Patients with durable CR and PR were classified as CR/PR, while non-responders (NR) exhibited stable or progressive disease. Relapse was classified as patients with initial CR and PR, followed by the development of progressive disease. The cut-off value of the exhaustion subsets was defined based on the median value of the frequency of PD1+ or PD1+TIGIT+ subsets in CD8+ CNCT19s.

    Statistical analysis

    Mann-Whitney U test or unpaired t-test with Mann-Whitney correction was used to compare the continuous variables. Categorical data were assessed using χ2 test or Fisher’s exact test. Response rates were presented as 95% CIs determined using the Clopper-Pearson method. PFS, DOR, DFS, and OS were assessed by generating Kaplan-Meier curves, and comparisons were made using the log-rank test. The 95% CI of survival was calculated using the survival (V.3.2–11) package of R (V.4.0.5; http://www.r-project.org). For data analysis, SPSS V.22.0 and GraphPad Prism V.7.0 were used. A two-sided p<0.05 was considered statistically significant.

    Results

    Patient characteristics

    In this study, a total of 30 patients were consecutively enrolled from December 2017 to June 2022. CNCT19s were successfully manufactured for 28 patients. Owing to failure of hematopoietic stem cell mobilization or other reasons, a total of 25 patients received the investigational treatment and were included in the safety and efficacy analysis (figure 1B). The median age was 48 (range 23–64) years old, and 64% comprised male patients. The included patients comprised the following: 14 (56%) with DLBCL, not otherwise specified; 5 (20%) with high-grade B-cell lymphoma (HGBL) with MYC, BCL2, and/or BCL6 rearrangement; 2 (8%) with primary mediastinal LBCL and 4 (16%) with transformed follicular lymphoma. TP53 deletion and/or mutation were detected in 10 of 16 (63%) patients. At the time of enrolment, 23 patients (92%) presented with refractory diseases, while 2 had relapsed disease (a detailed definition of refractory or relapsed disease is listed in the Methods section of online supplemental appendix). 20 patients (80%) exhibited resistance to the first-line immunochemotherapy of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) or R-DA-EPOCH (rituximab, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin). After enrolment, all patients underwent salvage or bridging therapy, with a median number of prior lines of therapy at transplantation being 3 (range 2–5). 16 patients (64%) still manifested progressive or stable disease at the time of transplantation and CNCT19 therapy. In table 1, patient demographics and characteristics are summarized.

    View this table:
    Table 1

    Demographic and characteristics of the patients at baseline

    Apheresis and reinfusion of hematopoietic stem cells and CNCT19 cells

    The median time from PBMC apheresis or CD34+ hematopoietic stem cells apheresis to the initiation of myeloablative high-dose chemotherapy was 31 days (range 8–105) and 43 days (range 10–132), respectively. Additionally, the median interval between the two apheresis sessions was 18 days (range 9–53). During transplantation, the median number of reinfused CD34+ hematopoietic stem cells was 2.8×106 (range 1.8–10.2×106) cells per kg/body weight. All patients only received peripheral blood stem cell infusion, except for one patient with poor mobilization who received both peripheral blood and bone marrow stem cell infusion concurrently. A median of 2.0×106 (range 1.6–4.0×106) CNCT19s per kg/body weight was administered to the patients. The median interval between CD34+ stem cell and CNCT19 infusion was 3 days (range 2–5 days). In one patient, CNCN19 infusion was delayed to day +5 due to suspicion of active infection.

    Safety

    All patients experienced grade 3 or higher adverse events. Common toxicities included cytopenia, fatigue, febrile neutropenia, diarrhea, and mucositis (table 2). Grade 3 or higher transaminase elevation was observed in 12% of patients, which was associated with GBC/M conditioning therapy. Unexpected toxicity or treatment-related deaths were not observed throughout the therapy. The median times to neutrophil and platelet recovery were 10 days (range 8–30 days) and 16.5 days (range 8–265 days) after stem cell reinfusion, respectively. At 3 months post-CNCT19 infusion, delayed grade 3 or higher cytopenia was observed in eight patients (32%), all of whom manifested thrombocytopenia, with three patients (12%) concurrently experiencing neutropenia (online supplemental table 2).

    View this table:
    Table 2

    Adverse events after HDT/ASCT and CNCT19 cells infusion, regardless of study treatment relationship

    CRS occurred in 22 patients (88%), and all were classified as having low grades of CRS (grade 1, 84%; grade 2, 4%) (table 2). The median time from CNCT19 infusion to the onset of CRS was 1 day (range 0–4 days), and the median time until resolution was 8 days (range 4–9 days). 52% of patients received tocilizumab and 28% received glucocorticoids for the management of CRS. The median interval between the onset of CRS and the administration of tocilizumab and glucocorticoids was 2 days for both. The median cumulative dose of glucocorticoids for CRS treatment was 17.5 mg (range 7.5–205) of dexamethasone equivalent dosage. Four patients (16%) experienced CRES, with two of them experiencing grade three or higher (table 2). After glucocorticoids treatment, all CRES instances were completely resolved.

    Efficacy

    As of April 26, 2023, the median follow-up from the CNCT19 infusion to the data cut-off date was 27.0 (95% CI 16.3 to 36.9) months. The best ORR was 92.0% (95% CI 74.0% to 99.0%), with a best CR rate of 72.0% (95% CI 50.6% to 87.9%) (figure 2). At 3 and 6 months after CNCT19 infusion, 80.0% and 72.0% of patients had an ongoing response, respectively (figure 2). The median PFS, DOR, DFS, and OS were not reached, and the 2-year PFS, DOR, DFS, and OS were 62.3% (95% CI 39.6% to 78.6%), 64.9% (95% CI 41.4% to 80.9%), 75.0% (95% CI 45.2% to 90.1%), and 68.5% (95% CI 44.4% to 83.8%), respectively (figure 3A–D). Of the patients with a durable response at 3 months or 6 months post-CNCT19 infusion, the 2-year PFS was 77.9% and 86.6%, respectively (online supplemental figure 1A–B).

    Figure 2
    Figure 2

    Response rates after HDT/ASCT and CNCT19 treatment. The best response rate and response rates at 3 and 6 months among 25 patients who received HDT/ASCT and CNCT19 therapy. HDT/ASCT, high-dose chemotherapy and autologous stem cell transplantation; ORR, overall response rate.

    Figure 3
    Figure 3

    Kaplan-Meier estimates of the progression-free survival, duration of response, disease-free survival, and overall survival. (A) Progression-free survival of the 25 patients who received HDT/ASCT and CNCT19 treatment. (B) Duration of response among 23 patients who achieved complete response or partial response. (C) Disease-free survival among 18 patients who attained complete response. (D) Overall survival of the total 25 patients. HDT/ASCT, high-dose chemotherapy and autologous stem cell transplantation; NE, not evaluable; NR, not reached.

    The disease status at enrolment had no impact on the response to the combinational therapy, with an ORR in patients with recurrent or refractory disease of 100% and 91.3% (p>0.999), respectively, and CR rates of 100% and 69.6% (p>0.999), respectively (online supplemental table 3). Patients who received three or more lines of prior therapy (3L+group, N=14) at transplantation exhibited a similar response to those receiving 2 lines of prior therapy (2L group, N=11). Following HDT/ASCT and CNCT19 treatment, the ORR in the 2L group and 3L+group was 100% and 85.7% (p=0.487), respectively, and the CR rates were 81.8% and 64.3% (p=0.407), respectively.

    CNCT19 pharmacokinetics

    CNCT19 levels peaked in the peripheral blood at a median of 10 days (range 7–16 days) after infusion (online supplemental figure 2). The median maximum expansion of CNCT19 was 468 cells/µL (range 98–4160), and the median area under the curve from 0 to 28 days postinfusion was 4499 cells/µL (range 539–33349). At 2 years, CNCT19s were detected in two patients who remained in continuous CR.

    Comparison of baseline characteristics between combinational therapy and monotherapy cohorts

    A total of 13 patients in the combinational therapy group (HDT/ASCT-CNCT19 cohort) and 18 patients in the CNCT19 monotherapy group (CNCT19 cohort) with available frozen PBMC samples were included in the exploratory analysis to compare the performance of CNCT19 in vivo between these cohorts. A comparison of baseline characteristics demonstrated that patients in both cohorts had similar profiles, except for the combinational therapy group, which had a younger median age (42 years vs 52 years, p=0.031), a higher proportion of HGBL (double-hit or triple-hit) (31% vs 0, p=0.023), and lowed number of CNCT19s infused (median, 2×106/kg vs 2.72×106/kg, p=0.002) (online supplemental table 1).

    Expansion capacity and exhaustion status of circulating CNCT19s postinfusion between combinational therapy and CNCT19 monotherapy

    The expansion ability of peripheral CNCT19s was assessed at weeks 1, 2, and 4 after infusion of the two cohorts (HDT/ASCT-CNCT19 and CNCT19) via flow cytometry. Our results revealed that patients in the HDT/ASCT-CNCT19 cohort showed significantly better CD8+ CAR T-cell expansion at 2 weeks compared with those in the CNCT19 cohort, both in terms of percentage and absolute cell number (figure 4A,B). Additionally, the CD4+ CAR T-cell expansion in the HDT/ASCT-CNCT19 cohort was remarkably better than that of the CNCT19 cohort at 1–4 weeks (figure 4C). No difference in CD8+ and CD4+ CAR− T-cell expansion was observed between these two cohorts (figure 4A–C). Furthermore, Ki67, as a cell proliferation indicator, was assessed via flow cytometry as well. A week after infusion, CAR T cells from both cohorts reached the highest proliferation rate (figure 4D and online supplemental figure 3A–B). The majority of CD8+ and CD4+ CAR T cells in the HDT/ASCT-CNCT19 cohort were Ki67+ (approximately 80% and 60%, respectively), significantly better than that of the CNCT19 cohort at 1 week after infusion (approximately 60% and 20%, respectively) (figure 4D). The Ki67+ cell proportion of CD8+ and CD4+ CAR T cells dramatically declined to ~20% in both cohorts at week 2 and further reduced in the CNCT19 cohort at week 4, leading to significantly less Ki67+ cells compared with that of the HDT/ASCT-CNCT19 cohort (figure 4D). In both groups, the CAR− T cells showed a poor proliferation capacity (figure 4E and online supplemental figure 3C–D).

    Figure 4
    Figure 4

    Expansion capacity and exhaustion status of circulating CD8+ CAR T-cell postinfusion between combinational therapy and CNCT19 monotherapy. The expansion capacity and exhaustion status of infused CAR T cells in the peripheral blood when comparing combinational therapy to CNCT19 monotherapy. (A) Representative flow cytometry data of the percentage of CAR T cells in T cells at 1,2, and 4 weeks post-CAR T infusion. (B) The percentage of CD8+ CAR T cells in live cells of PBMCs (left panel) and the absolute cell number of CD8+ CAR T cells (middle panel) and CD8+ CAR− T cells (right panel) post-CAR T infusion. (C) The percentage of CD4+ CAR T cells in live cells of PBMCs (left panel) and the absolute cell number of CD4+ CAR T cells (middle panel) and CD4+ CAR− T cells (right panel) post-CAR T infusion. The absolute cell number was calculated according to the percentage of subsets in the live cells of PBMCs and the number of white blood cells in the complete blood count test. (D) The percentage of proliferative Ki67+ subsets in CD8+ and CD4+ CAR T cells. (E) The percentage of proliferative Ki67+ subsets in CD8+ and CD4+ CAR− T cells. (F) The percentage of PD-1+ and PD-1+TIGIT+ subsets of CD8+ CAR T cells in the HDT/ASCT-CNCT19 cohort compared with that of the CNCT19 cohort 4 weeks after infusion. Data were presented as means±SEM. Statistical significance was determined using the unpaired T test with Mann-Whitney correction. *p<0.05, **p<0.01, ***p<0.001. HDT/ASCT, high-dose chemotherapy and autologous stem cell transplantation; PBMCs, peripheral blood mononuclear cell.

    The differentiation status of peripheral CNCT19s was measured since it was closely associated with the cytotoxic effector capacity of adoptively transferred T cells. CD8+ CAR T-cell in each cohort mainly differentiated into CCR7–CD45RO+ TEM and CCR7–CD45RO– TEMRA subsets after infusion (online supplemental figure 4A–B). Notably, 1 week after infusion, CD8+ CAR T-cell and CD4+ CAR T-cell in HDT/ASCT-CNCT19 cohort contained significantly less CCR7+CD45RO+ TCM subsets but more TEM subset compared with it of CNCT19 cohort, indicating its better cytotoxic effector capacity (online supplemental figure 4B–C). Nevertheless, CD8+ CAR– T cells in HDT/ASCT-CNCT19 cohort contained significantly less effector memory subset but more terminal differentiated effector T cells at 1 week (online supplemental figure 4D–E). There were no differences when compared the differentiation of CD4+ CAR– T cells within the two groups (online supplemental figure 4F).

    Furthermore, the exhaustion status of circulating CD8+ CAR T cells postinfusion was examined. As revealed in figure 4F and online supplemental figure 5, the frequency of PD-1+ and PD-1+TIGIT+ subsets of the CD8+ CAR T cells in the HDT/ASCT-CNCT19 cohort was considerably lower than that of the CNCT19 monotherapy cohort 4 weeks after infusion.

    The correlation between the exhaustion status of circulating CD8+ CNCT19s postinfusion and patient outcomes

    Next, we explored the correlation between clinical outcomes and the presence of PD1+ and/or TIGIT+ subsets within the CD8+ CNCT19s at 1–2 months after CNCT19 infusion. Patients from both cohorts were combined, and we observed that the frequency of the TIGIT+ subset in the CD8+ CNCT19s was significantly lower in patients with CR/PR 1–2 months after CNCT19 therapy than in patients with NR but not in patients who relapsed (figure 5A). Meanwhile, the frequency of the PD-1+ subset in CD8+ CNCT19s was significantly lower in the CR/PR patients than in both patients with NR and on relapse (figure 5B). Notably, the frequency of the PD-1+ TIGIT+ subset in CD8+ CNCT19s was correlated with each group (figure 5C), which was significantly highest in patients with NR and lowest in patients with CR/PR.

    Figure 5
    Figure 5

    PD-1 and TIGIT coexpression identifies a CAR T-cell subset predictive of long-term outcome in patients. The exhaustion status of circulating CAR T cells was classified based on the PD-1 and TIGIT expression of all patients in both cohorts with combinational therapy or CNCT19 monotherapy 3–8 weeks post-CAR T infusion. (A–C) The percentage of TIGIT+ (A), PD-1+ (B), and PD-1+TIGIT+ (C) subsets in the circulating CAR T cells according to patient outcomes. (D) Progression-free survival and overall survival difference between patients with PD-1+ subsets not less than 31% and those lower than 31%. (E) Progression-free survival and overall survival difference between patients with PD-1+TIGIT+ subsets not less than 8.6% and those lower than 8.6%. Data were indicated as means±SEM. Significance was determined using an unpaired t-test with Mann-Whitney correction (A–C) or log-rank (Mantel-Cox) test (D, E). *p<0.05, **p<0.01. CR, complete response; NR, non-responders; PR, partial response.

    Moreover, based on the median value of the frequency of PD1+ subsets in CD8+ CNCT19s of all the patients in two cohorts (n=28), 31% was identified as a potentially relevant value (cut-off value). The PFS of patients with PD1+ frequency in CD8+ CNCT19s <31% (n=14) was significantly better than that of patients with PD1+ frequency ≥31% (n=14, p=0.04) (figure 5D). Additionally, the cut-off value of the PD1+TIGIT+ frequency in CD8+ CNCT19s was 8.6% based on the median value of all the patients in the two cohorts. Patients with PD1+TIGIT+ frequency in CD8+ CNCT19s <8.6% (n=13) revealed a significantly better PFS than patients with PD1+TIGIT+ frequency ≥8.6% (n=15, p=0.0053) (figure 5E).

    Discussion

    In this study, we present the results of a phase I/II clinical trial investigating the administration of CNCT19s following HDT/ASCT in patients with aggressive B-cell lymphoma who were refractory to first-line and/or subsequent salvage therapy. The combinational therapy demonstrated a favorable safety profile, with no unexpected toxicity or grade 3 or higher CRS. Grade 3 or higher CRES occurred in only 8% of patients. Despite undergoing a median of three lines of prior therapy, patients achieved an ORR of 92.0% and a CR rate of 72.0%. The 2-year PFS and OS were 62.3% and 68.5%, respectively. Furthermore, a comparison of CNCT19 in vivo behavior between its administration as combinational therapy and monotherapy was conducted. Our findings showed that combinational therapy could enhance in vivo CNCT19 expansion and reduce long-term exhaustion formation.

    We did not observe any unexpected toxicities when administering CNCT19 cells immediately following HDT/ASCT. In this study, the incidence of transaminase elevation appeared to be relatively high. This adverse event was commonly observed following GBC/M conditioning24 and was transient, without an increased risk of liver damage after CAR T infusion. The incidence of CRS (88%) appeared to be higher than that in the pilot clinical trial of CNCT19 (69%).22 However, all cases of CRS were of low grade. Consistently, a similar incidence of CRS (96%) was reported during the administration of an anti-CD19 and anti-CD22 CAR T cells sequentially following HDT/ASCT, with a grade 3 CRS of 5%.31 The incidence of grade 3 or higher CRES was low in our study and other studies.31–34 However, in a study assessing the efficacy and safety of 19-28z CAR T-cell administration post-HDT/ASCT, a high incidence of severe neurotoxicity (10/15, 67%) was reported.35 The author postulates that the utilization of CD28 as the costimulatory domain of CAR T cells and the widespread administration of pegfilgrastim on day +1 following HDT-ASCT may have contributed to the elevated incidence of severe neurotoxicity. As CNCT19s showed a low incidence of neurotoxicity in the previous study,22 further investigation is warranted to explore whether different CAR T-cell products are associated with varying risks of neurotoxicity during combinational therapy.

    CD19-directed CAR T-cell therapy was the preferred therapy for patients with R/R LBCL who had failed two or more lines of prior therapy or relapsed after HDT/ASCT. In the pivotal clinical trials of three approved anti-CD19 CAR T products (axicabtagene ciloleucel (axi-cel), tisagenlecleucel (tisa-cel), and lisocabtagene maraleucel (liso-cel)) in R/R LBCL, 52%–83% of patients achieved a response and 40%–58% achieved a CR, with a median PFS of 2.9–6.7 months and a median OS of 11.1–21.1 months, respectively.6–8 CNCT19s showed comparable efficacy in a pilot study comprising 16 patients with R/R LBCL (N=15) or FL3B (N=1).22 The ORR was 75.0%, with a CR rate of 37.5%. After a median follow-up of 44.5 months, the median PFS and OS were 6.5 months and 12.7 months, respectively. In the current study, instead of administering CNCT19 alone, we infused CNCT19 following HDT/ASCT. The ORR and CR rates increased to 92.0% and 72.0%. The median PFS and OS were not reached after a median follow-up of 27.0 months, indicating a potentially improved efficacy when combining CNCT19 with HDT/ASCT therapy. Recently, a similarly encouraging result was documented in a clinical trial with third-generation anti-CD19 and anti-CD22 CAR T cells sequentially administered following HDT/ASCT in 42 patients with aggressive B-cell non-Hodgkin’s lymphoma (NHL) who had PET-positive disease after at least two cycles of salvage chemotherapy, with a 2-year PFS and OS of 83.3% each.32 Furthermore, they observed improved survival in cases with TP53 alterations or central nervous system involvement when treated with this combinational therapy.36 37

    Several studies have shown that a higher CAR T cells in vivo expansion is associated with improved efficacy in R/R B-cell lymphoma.7 38 39 Lymphodepletion prior to CAR T-cell infusion is crucial for CAR T cells in vivo proliferation. Turtle et al reported that adding fludarabine to cyclophosphamide lymphodepletion yielded higher interleukin (IL)-7 and IL-15 serum concentrations, increased CAR T-cell expansion and persistence, and higher response rates in patients with R/R NHL.16 Another method of lymphodepletion enhancement is myeloablative conditioning. Myeloablative lymphodepletion increases the ability to eliminate immunosuppressive elements (such as regulatory T cells and myeloid-derived suppressor cells) and reduces surviving host lymphocytes, which can inhibit transferred T-cell expansion and consume cytokines.19 Myeloablative conditioning also upregulates lymphocyte homeostatic cytokines IL-7 and IL-15 compared with nonmyeloablative chemotherapy.40 Furthermore, hematopoietic stem cells can directly cause a robust expansion of adoptively transferred tumor-specific CD8+ T cells.19 In this study, a higher proliferation of CNCT19s in vivo was noted in the combinational therapy cohort, despite significantly fewer CNCT19s being infused in this group than in the monotherapy cohort. This observation suggests that HDT/ASCT has a similarly positive impact on CAR T-cell proliferation.

    T-cell exhaustion is also closely related to CAR T-cell failure.6 41–43 Exhaustion-related chronic interferon signaling regulated by IRF7 of premanufactured T cells of patients was associated with poor CAR T-cell persistence.44 Additionally, exhaustion features (LAG3+TIM3+) of preinfusion CAR T cells were correlated with poor outcomes in patients with LBCL.45 Here, our study identified different circulating exhaustion subsets postinfusion, including TIGIT+, PD-1+, and PD-1+TIGIT+ in CD8+ CNCT19s, and were associated with poor outcomes in patients with R/R LBCL. CAR T-cell dysfunction marked by TIGIT expression postinfusion was associated with poor response in patients with NHL when comparing patients with CR/PR to patients with NR.46 Consistently, our results demonstrated that patients with NR maintained a higher frequency of TIGIT+ in CD8+ CNCT19s than patients with CR/PR. Notably, the frequency of the PD-1+TIGIT+ subset in CD8+ CNCT19s at 1–2 months postinfusion in the peripheral blood appears to be predictive of the durable responses to CNCT19 therapy targeting R/R DLBCL. Thus, patients with combinational therapy retained fewer exhaustion subsets postinfusion than patients with CNCT19 monotherapy, which may be associated with the potentially improved patient outcomes.

    In summary, the findings of this trial indicate that HDT/ASCT-CNCT19 combinational therapy is a feasible therapy for transplantation-eligible R/R LBCL patients with potentially improved efficacy and controlled safety. This improvement may be attributed to the enhanced expansion ability and diminished long-term exhaustion of CNCT19s postinfusion in combinational therapy compared with CNCT19 monotherapy. Given the single-arm design and the limited number of cases in this study, conducting randomized clinical trials comparing combinational therapy with CAR T-cell monotherapy could provide more robust evidence for the advantages of combinational therapy.

    Data availability statement

    Data are available on reasonable request. The deidentified participant data of this study are available from the corresponding author (email: zoudehui@ihcams.ac.cn) on reasonable request. Reuse of the data requires permission from all corresponding authors.

    Ethics statements

    Patient consent for publication

    Ethics approval

    This study involves human participants and was approved by the Ethics Committee of the Blood Diseases Hospital, Chinese Academy of Medical Sciences, with the approval number IIT2020013-EC-2. Participants gave informed consent to participate in the study before taking part.

    Acknowledgments

    We thank the patients, their families and caregivers for participating in the trial. We thank Juventas Cell Therapy for providing CNCT19 cell.

    References

    1. ↵
      2. Hitz F ,
      3. Connors JM ,
      4. Gascoyne RD , et al
      . Outcome of patients with primary refractory diffuse large B cell lymphoma after R-CHOP treatment. Ann Hematol 2015;94:1839–43. doi:10.1007/s00277-015-2467-z
      OpenUrl
    2. ↵
      2. Crump M ,
      3. Neelapu SS ,
      4. Farooq U , et al
      . Outcomes in refractory diffuse large B-cell lymphoma: results from the International SCHOLAR-1 study. Blood 2017;130:1800–8. doi:10.1182/blood-2017-03-769620
      OpenUrlAbstract/FREE Full Text
    3. ↵
      2. Van Den Neste E ,
      3. Schmitz N ,
      4. Mounier N , et al
      . Outcome of patients with relapsed diffuse large B-cell lymphoma who fail second-line salvage regimens in the International CORAL study. Bone Marrow Transplant 2016;51:51–7. doi:10.1038/bmt.2015.213
      OpenUrlCrossRefPubMed
    4. ↵
      2. Costa LJ ,
      3. Maddocks K ,
      4. Epperla N , et al
      . Diffuse large B-cell lymphoma with primary treatment failure: ultra-high risk features and benchmarking for experimental therapies. Am J Hematol 2017;92:161–70. doi:10.1002/ajh.24615
      OpenUrl
    5. ↵
      2. Ayers EC ,
      3. Li S ,
      4. Medeiros LJ , et al
      . Outcomes in patients with aggressive B-cell non-hodgkin lymphoma after intensive frontline treatment failure. Cancer 2020;126:293–303. doi:10.1002/cncr.32526
      OpenUrlCrossRef
    6. ↵
      2. Abramson JS ,
      3. Palomba ML ,
      4. Gordon LI , et al
      . Lisocabtagene maraleucel for patients with relapsed or refractory large B-cell lymphomas (TRANSCEND NHL 001): a multicentre seamless design study. Lancet 2020;396:839–52. doi:10.1016/S0140-6736(20)31366-0
      OpenUrlCrossRefPubMed
    7. ↵
      2. Neelapu SS ,
      3. Locke FL ,
      4. Bartlett NL , et al
      . Axicabtagene ciloleucel CAR T-cell therapy in refractory large B-cell lymphoma. N Engl J Med 2017;377:2531–44. doi:10.1056/NEJMoa1707447
      OpenUrlCrossRefPubMed
    8. ↵
      2. Schuster SJ ,
      3. Bishop MR ,
      4. Tam CS , et al
      . Tisagenlecleucel in adult relapsed or refractory diffuse large B-cell lymphoma. N Engl J Med 2019;380:45–56. doi:10.1056/NEJMoa1804980
      OpenUrlCrossRefPubMed
    9. ↵
      2. Locke FL ,
      3. Ghobadi A ,
      4. Jacobson CA , et al
      . Long-term safety and activity of axicabtagene ciloleucel in refractory large B-cell lymphoma (ZUMA-1): a single-arm, multicentre, phase 1-2 trial. Lancet Oncol 2019;20:31–42. doi:10.1016/S1470-2045(18)30864-7
      OpenUrlCrossRefPubMed
    10. ↵
      2. Schuster SJ ,
      3. Tam CS ,
      4. Borchmann P , et al
      . Long-term clinical outcomes of tisagenlecleucel in patients with relapsed or refractory aggressive B-cell lymphomas (JULIET): a multicentre, open-label, single-arm, phase 2 study. Lancet Oncol 2021;22:1403–15. doi:10.1016/S1470-2045(21)00375-2
      OpenUrlCrossRef
    11. ↵
      2. Bachy E ,
      3. Le Gouill S ,
      4. Di Blasi R , et al
      . A real-world comparison of tisagenlecleucel and axicabtagene ciloleucel CAR T cells in relapsed or refractory diffuse large B cell lymphoma. Nat Med 2022;28:2145–54. doi:10.1038/s41591-022-01969-y
      OpenUrlCrossRef
    12. ↵
      2. Chow VA ,
      3. Gopal AK ,
      4. Maloney DG , et al
      . Outcomes of patients with large B-cell lymphomas and progressive disease following CD19-specific CAR T-cell therapy. Am J Hematol 2019;94:E209–13. doi:10.1002/ajh.25505
      OpenUrlCrossRefPubMed
    13. ↵
      2. Spiegel JY ,
      3. Dahiya S ,
      4. Jain MD , et al
      . Outcomes of patients with large B-cell lymphoma progressing after axicabtagene ciloleucel therapy. Blood 2021;137:1832–5. doi:10.1182/blood.2020006245
      OpenUrlCrossRef
    14. ↵
      2. Del Toro-Mijares R ,
      3. Oluwole O ,
      4. Jayani RV , et al
      . Relapsed or refractory large B-cell lymphoma after chimeric antigen receptor T-cell therapy: current challenges and therapeutic options. Br J Haematol 2023;201:15–24. doi:10.1111/bjh.18656
      OpenUrl
    15. ↵
      2. Klebanoff CA ,
      3. Khong HT ,
      4. Antony PA , et al
      . Sinks, suppressors and antigen presenters: how lymphodepletion enhances T cell-mediated tumor immunotherapy. Trends Immunol 2005;26:111–7. doi:10.1016/j.it.2004.12.003
      OpenUrlCrossRefPubMedWeb of Science
    16. ↵
      2. Turtle CJ ,
      3. Hanafi L-A ,
      4. Berger C , et al
      . Immunotherapy of non-hodgkin’s lymphoma with a defined ratio of CD8+ and CD4+ CD19-specific chimeric antigen receptor-modified T cells. Sci Transl Med 2016;8:355ra116. doi:10.1126/scitranslmed.aaf8621
    17. ↵
      2. Hirayama AV ,
      3. Gauthier J ,
      4. Hay KA , et al
      . The response to lymphodepletion impacts PFS in patients with aggressive non-hodgkin lymphoma treated with CD19 CAR T cells. Blood 2019;133:1876–87. doi:10.1182/blood-2018-11-887067
      OpenUrlAbstract/FREE Full Text
    18. ↵
      2. Dean EA ,
      3. Mhaskar RS ,
      4. Lu H , et al
      . High metabolic tumor volume is associated with decreased efficacy of axicabtagene ciloleucel in large B-cell lymphoma. Blood Adv 2020;4:3268–76. doi:10.1182/bloodadvances.2020001900
      OpenUrlCrossRef
    19. ↵
      2. Wrzesinski C ,
      3. Paulos CM ,
      4. Gattinoni L , et al
      . Hematopoietic stem cells promote the expansion and function of adoptively transferred antitumor CD8 T cells. J Clin Invest 2007;117:492–501. doi:10.1172/JCI30414
      OpenUrlCrossRefPubMedWeb of Science
    20. ↵
      2. An N ,
      3. Tao Z ,
      4. Li S , et al
      . Construction of a new anti-CD19 chimeric antigen receptor and the anti-leukemia function study of the transduced T cells. Oncotarget 2016;7:10638–49. doi:10.18632/oncotarget.7079
      OpenUrlPubMed
    21. ↵
      2. Gu R ,
      3. Liu F ,
      4. Zou D , et al
      . Efficacy and safety of CD19 CAR T constructed with a new anti-CD19 chimeric antigen receptor in relapsed or refractory acute lymphoblastic leukemia. J Hematol Oncol 2020;13:122. doi:10.1186/s13045-020-00953-8
    22. ↵
      2. Liu W ,
      3. Huang W ,
      4. Lv R , et al
      . CNCT19 CAR T-cell therapy in relapsed or refractory B-cell lymphoma: long-term results of a pilot prospective clinical study. Blood 2022;140:4598–9. doi:10.1182/blood-2022-167104
      OpenUrl
    23. ↵
      2. Liu H ,
      3. Liu W ,
      4. Li R , et al
      . A gemcitabine-based regimen followed by autologous stem cell transplantation show high efficacy and well tolerance in malignant lymphoma. Bone Marrow Transplant 2022;57:1017–20. doi:10.1038/s41409-022-01655-0
      OpenUrl
    24. ↵
      2. Nieto Y ,
      3. Thall P ,
      4. Valdez B , et al
      . High-dose infusional gemcitabine combined with busulfan and melphalan with autologous stem-cell transplantation in patients with refractory lymphoid malignancies. Biol Blood Marrow Transplant 2012;18:1677–86. doi:10.1016/j.bbmt.2012.05.011
      OpenUrlCrossRefPubMed
    25. ↵
      2. Neelapu SS ,
      3. Tummala S ,
      4. Kebriaei P , et al
      . Chimeric antigen receptor T-cell therapy - assessment and management of toxicities. Nat Rev Clin Oncol 2018;15:47–62. doi:10.1038/nrclinonc.2017.148
      OpenUrlCrossRefPubMed
    26. ↵
      2. Cheson BD ,
      3. Fisher RI ,
      4. Barrington SF , et al
      . Recommendations for initial evaluation, staging, and response assessment of hodgkin and non-hodgkin lymphoma: the lugano classification. J Clin Oncol 2014;32:3059–68. doi:10.1200/JCO.2013.54.8800
      OpenUrlAbstract/FREE Full Text
    27. ↵
      2. Barrington SF ,
      3. Mikhaeel NG ,
      4. Kostakoglu L , et al
      . Role of imaging in the staging and response assessment of lymphoma: consensus of the international conference on malignant lymphomas imaging working group. J Clin Oncol 2014;32:3048–58. doi:10.1200/JCO.2013.53.5229
      OpenUrlAbstract/FREE Full Text
    28. ↵
      2. Johnston RJ ,
      3. Comps-Agrar L ,
      4. Hackney J , et al
      . The immunoreceptor TIGIT regulates antitumor and antiviral CD8(+) T cell effector function. Cancer Cell 2014;26:923–37. doi:10.1016/j.ccell.2014.10.018
      OpenUrlCrossRefPubMed
    29. ↵
      2. Nguyen LT ,
      3. Ohashi PS
      . Clinical blockade of PD1 and LAG3--potential mechanisms of action. Nat Rev Immunol 2015;15:45–56. doi:10.1038/nri3790
      OpenUrlCrossRefPubMed
    30. ↵
      2. Schildberg FA ,
      3. Klein SR ,
      4. Freeman GJ , et al
      . Coinhibitory pathways in the B7-CD28 ligand-receptor family. Immunity 2016;44:955–72. doi:10.1016/j.immuni.2016.05.002
      OpenUrlPubMed
    31. ↵
      2. Wang X ,
      3. Popplewell LL ,
      4. Wagner JR , et al
      . Phase 1 studies of central memory-derived CD19 CAR T-cell therapy following autologous HSCT in patients with B-cell NHL. Blood 2016;127:2980–90. doi:10.1182/blood-2015-12-686725
      OpenUrlAbstract/FREE Full Text
    32. ↵
      2. Cao Y ,
      3. Xiao Y ,
      4. Wang N , et al
      . CD19/CD22 chimeric antigen receptor T cell cocktail therapy following autologous transplantation in patients with relapsed/refractory aggressive B cell lymphomas. Transplant Cell Ther 2021;27:910. doi:10.1016/j.jtct.2021.08.012
      OpenUrl
    33. ↵
      2. Kebriaei P ,
      3. Singh H ,
      4. Huls MH , et al
      . Phase I trials using sleeping beauty to generate CD19-specific CAR T cells. J Clin Invest 2016;126:3363–76. doi:10.1172/JCI86721
      OpenUrlCrossRefPubMed
    34. ↵
      2. Wang T ,
      3. Gao L ,
      4. Wang Y , et al
      . Hematopoietic stem cell transplantation and chimeric antigen receptor T cell for relapsed or refractory diffuse large B-cell lymphoma. Immunotherapy 2020;12:997–1006. doi:10.2217/imt-2020-0075
      OpenUrl
    35. ↵
      2. Sauter CS ,
      3. Senechal B ,
      4. Rivière I , et al
      . CD19 CAR T cells following autologous transplantation in poor-risk relapsed and refractory B-cell non-hodgkin lymphoma. Blood 2019;134:626–35. doi:10.1182/blood.2018883421
      OpenUrlAbstract/FREE Full Text
    36. ↵
      2. Wei J ,
      3. Xiao M ,
      4. Mao Z , et al
      . Outcome of aggressive B-cell lymphoma with TP53 alterations administered with CAR T-cell cocktail alone or in combination with ASCT. Signal Transduct Target Ther 2022;7:101. doi:10.1038/s41392-022-00924-0
    37. ↵
      2. Wu J ,
      3. Meng F ,
      4. Cao Y , et al
      . Sequential CD19/22 CAR T-cell immunotherapy following autologous stem cell transplantation for central nervous system lymphoma. Blood Cancer J 2021;11:131. doi:10.1038/s41408-021-00523-2
    38. ↵
      2. Wang M ,
      3. Munoz J ,
      4. Goy A , et al
      . KTE-X19 CAR T-cell therapy in relapsed or refractory mantle-cell lymphoma. N Engl J Med 2020;382:1331–42. doi:10.1056/NEJMoa1914347
      OpenUrlCrossRefPubMed
    39. ↵
      2. Ogasawara K ,
      3. Lymp J ,
      4. Mack T , et al
      . In vivo cellular expansion of lisocabtagene maraleucel and association with efficacy and safety in relapsed/refractory large B-cell lymphoma. Clin Pharmacol Ther 2022;112:81–9. doi:10.1002/cpt.2561
      OpenUrlPubMed
    40. ↵
      2. Dudley ME ,
      3. Yang JC ,
      4. Sherry R , et al
      . Adoptive cell therapy for patients with metastatic melanoma: evaluation of intensive myeloablative chemoradiation preparative regimens. J Clin Oncol 2008;26:5233–9. doi:10.1200/JCO.2008.16.5449
      OpenUrlAbstract/FREE Full Text
    41. ↵
      2. Frank MJ ,
      3. Hossain NM ,
      4. Bukhari A , et al
      . Monitoring of circulating tumor DNA improves early relapse detection after axicabtagene ciloleucel infusion in large B-cell lymphoma: results of a prospective multi-institutional trial. J Clin Oncol 2021;39:3034–43. doi:10.1200/JCO.21.00377
      OpenUrlPubMed
    42. ↵
      2. Locke FL ,
      3. Rossi JM ,
      4. Neelapu SS , et al
      . Tumor burden, inflammation, and product attributes determine outcomes of axicabtagene ciloleucel in large B-cell lymphoma. Blood Adv 2020;4:4898–911. doi:10.1182/bloodadvances.2020002394
      OpenUrlCrossRefPubMed
    43. ↵
      2. Nastoupil LJ ,
      3. Jain MD ,
      4. Feng L , et al
      . Standard-of-care axicabtagene ciloleucel for relapsed or refractory large B-cell lymphoma: results from the US lymphoma CAR T consortium. J Clin Oncol 2020;38:3119–28. doi:10.1200/JCO.19.02104
      OpenUrlCrossRefPubMed
    44. ↵
      2. Chen GM ,
      3. Chen C ,
      4. Das RK , et al
      . Integrative bulk and single-cell profiling of premanufacture T-cell populations reveals factors mediating long-term persistence of CAR T-cell therapy. Cancer Discov 2021;11:2186–99. doi:10.1158/2159-8290.CD-20-1677
      OpenUrlAbstract/FREE Full Text
    45. ↵
      2. Deng Q ,
      3. Han G ,
      4. Puebla-Osorio N , et al
      . Characteristics of anti-CD19 CAR T cell infusion products associated with efficacy and toxicity in patients with large B cell lymphomas. Nat Med 2020;26:1878–87. doi:10.1038/s41591-020-1061-7
      OpenUrlPubMed
    46. ↵
      2. Jackson Z ,
      3. Hong C ,
      4. Schauner R , et al
      . Sequential single-cell transcriptional and protein marker profiling reveals TIGIT as a marker of CD19 CAR-T cell dysfunction in patients with non-hodgkin lymphoma. Cancer Discov 2022;12:1886–903. doi:10.1158/2159-8290.CD-21-1586
      OpenUrlCrossRefPubMed

    Supplementary materials

    • Supplementary Data

      This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.

    Footnotes

    • WL, WL, HZ and LC contributed equally.

    • Correction notice This article has been corrected since it was first published. The second author Wei Liu was missing and has now been added.

    • Contributors DZ and LQ contributed to the study’s conception and design of the study and served as the principal investigators; WZ and JW contributed to the conception and design of the study; DZ and WZ are the guarantors; WL contributed to the design of the study, protocol drafting, patients screening and treatment, data collection and analysis, and manuscript writing; WL, HZ and LC contributed to sample processing, flow cytometry analysis, data extraction and analysis, and manuscript writing. WH, RL, YX, HL, YW, WX, SD, SY, WS and GP contributed to patients enrolment and treatment; YS and HW contributed to the measurement of CNCT19 proliferation in vivo; KW contributed to sample processing and flow cytometry analysis; YM contributed to statistical analysis and produced graphs; LL contributed to the provision of CNCT19 products; JWang contributed to the CAR and product design and the conception and design of the study.

    • Funding This work was supported by the CAMS Innovation Fund for Medical Sciences (CIFMS) (2021-I2M-1-041, 2022-I2M-1-022, 2020-I2M-C&T-B-085, 2022-I2M-C&T-B-089), the National Nature Science Foundation of China (82101933, 82341214, 32230055), the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (2022-RC320-01, 2021-RC310-011), the Distinguished Young Scholars of Tianjin (22JCJQJC00070), Tianjin Municipal Science and Technology Plan Program (22ZYCGSY00830), the Haihe Laboratory of Cell Ecosystem Innovation Fund (HH24KYZX0004).

    • Competing interests None declared.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.