Original Article

Axicabtagene Ciloleucel CAR T-Cell Therapy in Refractory Large B-Cell Lymphoma

List of authors.
  • Sattva S. Neelapu, M.D.,
  • Frederick L. Locke, M.D.,
  • Nancy L. Bartlett, M.D.,
  • Lazaros J. Lekakis, M.D.,
  • David B. Miklos, M.D., Ph.D.,
  • Caron A. Jacobson, M.D., M.M.Sc.,
  • Ira Braunschweig, M.D.,
  • Olalekan O. Oluwole, M.B., B.S., M.P.H.,
  • Tanya Siddiqi, M.D.,
  • Yi Lin, M.D., Ph.D.,
  • John M. Timmerman, M.D.,
  • Patrick J. Stiff, M.D.,
  • Jonathan W. Friedberg, M.D., M.M.Sc.,
  • Ian W. Flinn, M.D., Ph.D.,
  • Andre Goy, M.D.,
  • Brian T. Hill, M.D., Ph.D.,
  • Mitchell R. Smith, M.D., Ph.D.,
  • Abhinav Deol, M.D.,
  • Umar Farooq, M.D.,
  • Peter McSweeney, M.D.,
  • Javier Munoz, M.D.,
  • Irit Avivi, M.D.,
  • Januario E. Castro, M.D.,
  • Jason R. Westin, M.D.,
  • Julio C. Chavez, M.D.,
  • Armin Ghobadi, M.D.,
  • Krishna V. Komanduri, M.D.,
  • Ronald Levy, M.D.,
  • Eric D. Jacobsen, M.D.,
  • Thomas E. Witzig, M.D.,
  • Patrick Reagan, M.D.,
  • Adrian Bot, M.D., Ph.D.,
  • John Rossi, M.S.,
  • Lynn Navale, M.S.,
  • Yizhou Jiang, Ph.D.,
  • Jeff Aycock, B.A.,
  • Meg Elias, R.N., B.S.N.,
  • David Chang, M.D., Ph.D.,
  • Jeff Wiezorek, M.D.,
  • and William Y. Go, M.D., Ph.D.

Abstract

Background

In a phase 1 trial, axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, showed efficacy in patients with refractory large B-cell lymphoma after the failure of conventional therapy.

Methods

In this multicenter, phase 2 trial, we enrolled 111 patients with diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, or transformed follicular lymphoma who had refractory disease despite undergoing recommended prior therapy. Patients received a target dose of 2×106 anti-CD19 CAR T cells per kilogram of body weight after receiving a conditioning regimen of low-dose cyclophosphamide and fludarabine. The primary end point was the rate of objective response (calculated as the combined rates of complete response and partial response). Secondary end points included overall survival, safety, and biomarker assessments.

Results

Among the 111 patients who were enrolled, axi-cel was successfully manufactured for 110 (99%) and administered to 101 (91%). The objective response rate was 82%, and the complete response rate was 54%.With a median follow-up of 15.4 months, 42% of the patients continued to have a response, with 40% continuing to have a complete response. The overall rate of survival at 18 months was 52%. The most common adverse events of grade 3 or higher during treatment were neutropenia (in 78% of the patients), anemia (in 43%), and thrombocytopenia (in 38%). Grade 3 or higher cytokine release syndrome and neurologic events occurred in 13% and 28% of the patients, respectively. Three of the patients died during treatment. Higher CAR T-cell levels in blood were associated with response.

Conclusions

In this multicenter study, patients with refractory large B-cell lymphoma who received CAR T-cell therapy with axi-cel had high levels of durable response, with a safety profile that included myelosuppression, the cytokine release syndrome, and neurologic events. (Funded by Kite Pharma and the Leukemia and Lymphoma Society Therapy Acceleration Program; ZUMA-1 ClinicalTrials.gov number, NCT02348216.)

Introduction

Large B-cell lymphomas, including diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, and transformed follicular lymphoma, are treated with combination chemoimmunotherapy at diagnosis.1-3 Patients who have a relapse with chemotherapy-sensitive disease may be treated with high-dose chemotherapy followed by autologous stem-cell transplantation.1-3 However, patients who have disease that is resistant to primary or salvage chemoimmunotherapy or who have had a relapse after transplantation have an extremely poor prognosis.4-13 Recently, in a large, international, retrospective research study involving patients with non-Hodgkin’s lymphoma (SCHOLAR-1), investigators found an objective response rate of 26%, a complete response rate of 7%, and a median overall survival of 6.3 months with existing therapies among patients who had aggressive B-cell lymphoma that was resistant to chemotherapy or who had a relapse within 12 months after autologous stem-cell transplantation.14

Single-institution studies of anti-CD19 chimeric antigen receptor (CAR) T-cell therapy have shown high response rates in refractory B-cell lymphomas after the failure of conventional therapy.15-19 Investigators at the National Cancer Institute have found that many responses have been ongoing beyond 4 years, which suggests that this therapy may be potentially curative.15-17 Axicabtagene ciloleucel (axi-cel, Kite Pharma) is an autologous anti-CD19 CAR T-cell therapy that uses the same CAR construct that was developed at the National Cancer Institute.15-17,20 It consists of a single-chain variable fragment extracellular domain targeting CD19 proteins with CD3ζ (also called CD247) and CD28 intracellular domains that signal T-cell activation.20 In this therapy, T cells that have been removed from a patient are genetically engineered to express anti-CD19 CARs and are then injected back into the patient.

A phase 1 multicenter study (ZUMA-1) involving seven patients with refractory large B-cell lymphoma showed that axi-cel could be centrally manufactured and safely administered.21 An overall response to axi-cel therapy was reported in five patients and a complete response in four patients, with an ongoing complete response in three patients reported at 1 year.21 Here, we report the results of the primary analysis of phase 2 of ZUMA-1 and an updated analysis with 1 year of follow-up.

Methods

Patients and Study Design

The study was approved by the institutional review board at each study site and was conducted in accordance with the Good Clinical Practice guidelines of the International Conference on Harmonisation. All the patients provided written informed consent. The study was designed by employees of Kite Pharma, which also paid for medical-writing support. All the authors discussed and interpreted the results and vouch for the completeness and accuracy of the data and analyses and for the adherence of the study to the protocol, available with the full text of this article at NEJM.org. All the authors contributed to the conduct of the study, data analyses, and writing of the manuscript.

The phase 2 treatment portion of the study ran from November 2015 through September 2016 at 22 study centers (21 in the United States and 1 in Israel). (A complete list of study sites is provided in the Supplementary Appendix, available at NEJM.org.) Follow-up to evaluate the duration of response, survival, and late adverse events is ongoing.

All the patients had histologically confirmed large B-cell lymphoma, including diffuse large B-cell lymphoma (cohort 1) and primary mediastinal B-cell lymphoma or transformed follicular lymphoma (cohort 2), on the basis of the 2008 World Health Organization guidelines.22 Central confirmation of the diagnosis was performed retrospectively. Patients had refractory disease, which was defined as progressive or stable disease as the best response to the most recent chemotherapy regimen or disease progression or relapse within 12 months after autologous stem-cell transplantation. Eligibility criteria and therapy were similar to those in the phase 1 study (see the Methods section in the Supplementary Appendix).21

After leukapheresis and axi-cel manufacturing, patients received fixed low-dose conditioning chemotherapy consisting of fludarabine (at a dose of 30 mg per square meter of body-surface area per day) and cyclophosphamide (at a dose of 500 mg per square meter per day) on days −5, −4, and −3 before the administration of a single intravenous infusion of axi-cel at a target dose of 2×106 CAR T cells per kilogram of body weight (on day 0).21 Systemic bridging chemotherapy was not allowed after leukapheresis and before the administration of axi-cel. Patients who had an initial response and then had disease progression at least 3 months after the first dose of axi-cel could be retreated.

End Points and Assessments

The primary end point was the rate of objective response (calculated as the combined rates of complete response and partial response), as assessed by the investigators according to the International Working Group Response Criteria for Malignant Lymphoma.23 Secondary end points included the duration of response, progression-free survival, overall survival, incidence of adverse events, and blood levels of CAR T cells and serum cytokines. The cytokine release syndrome was graded according to the criteria of Lee et al.24 We used the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.03, to grade symptoms of the cytokine release syndrome and neurologic events along with other adverse events. CAR T-cell expansion and serum cytokines, and their associations with clinical outcomes, were analyzed as described previously.21,25 The cell-of-origin subtype was assessed centrally by means of the NanoString Lymphoma Subtyping Test.26 Details regarding the response criteria, grading of the cytokine release syndrome, and calculation of the CD19 histologic score are provided in the Methods section in the Supplementary Appendix.

Statistical Analysis

The primary analysis was conducted at the point when 92 patients could be evaluated 6 months after the axi-cel infusion. Efficacy and safety analyses were reported in the modified intention-to-treat population of all the patients who had received axi-cel. We also performed an updated analysis of all the patients who had been treated in phase 121 and phase 2 of ZUMA-1.

To analyze the response rate, we used a single-group design in which we compared the response of patients with a prespecified rate of response of 20% on the basis of historical values for refractory diffuse large B-cell lymphoma.4-12 Efficacy testing had a power of at least 90% to distinguish between an active therapy with a 40% true response rate and a therapy with a response rate of 20% or less with the use of a one-sided alpha level of 0.025. The primary end point was tested with an exact binomial test. We used the Wilcoxon rank-sum test to measure the associations between outcomes and levels of CAR T cells and cytokines, with P values adjusted using Holm’s procedure. Confidence intervals were calculated with the use of the Clopper–Pearson method.

Results

Patients

Table 1. Table 1. Treatment Disposition and Baseline Characteristics of the Patients.

A total of 111 patients were enrolled in the study. Axi-cel was manufactured for 110 patients (99%) and administered to 101 patients (91%); the latter population was included in the modified intention-to-treat analysis. Patients included 77 with diffuse large B-cell lymphoma and 24 with primary mediastinal B-cell lymphoma or transformed follicular lymphoma (Table 1, and Fig. S1 in the Supplementary Appendix). The date of data cutoff for the primary analysis was January 27, 2017; the median follow-up was 8.7 months. The cutoff date for the updated analysis was August 11, 2017, which resulted in a median follow-up of 15.4 months.

The median time from leukapheresis to delivery of axi-cel to the treatment facility was 17 days. Of the 10 patients who did not receive axi-cel, 1 had unsuccessful manufacture of the CAR T-cell product, 4 had adverse events, 1 died from disease progression, and 2 had nonmeasurable disease before conditioning chemotherapy. After conditioning chemotherapy but before axi-cel infusion, 1 patient had sepsis and 1 died from multiple factors with laboratory abnormalities suggestive of the tumor lysis syndrome, gastrointestinal bleeding and perforation, and disease progression.

Among the patients who were treated with axi-cel, the median age was 58 years (range, 23 to 76). Most of the patients (85%) had stage III or IV disease; 77% had disease that was resistant to second-line or later therapies, 21% had disease relapse after transplantation, 69% had received at least three previous therapies, and 26% had a history of primary refractory disease (Table 1).

Efficacy

Primary Analysis

Figure 1. Figure 1. Objective Response Rate among the 101 Treated Patients.

Panel A shows the objective response rate (ORR; calculated as complete response [CR] plus partial response [PR]) among the patients who received axicabtagene ciloleucel (axi-cel), an anti-CD19 chimeric antigen receptor T-cell therapy, as well as the response among the patients with stable disease (SD), disease progression (PD), and those who could not be evaluated (NE). The patients in the modified intention-to-treat population were evaluated according to the two main disease cohorts: diffuse large B-cell lymphoma (DLBCL) and either primary mediastinal large B-cell lymphoma (PMBCL) or transformed follicular lymphoma (TLF). The numbers in parentheses indicate the number of patients who had the specified response. On independent central review, the objective response rate was 71%, including a complete response rate of 51% and a partial response rate of 20%. Panel B shows the subgroup analysis of the objective response rate for key baseline and clinical covariates. Scores on the International Prognostic Index (IPI) include low risk (0 or 1 point), low-intermediate risk (2 points), high-intermediate risk (3 points), and high risk (4 or 5 points). The 95% confidence interval (CI) was calculated with the use of the Clopper–Pearson method. ASCT denotes autologous stem-cell transplantation.

At a minimum of 6 months of follow-up, the objective response rate among the protocol-specified 92 patients was 82% (95% confidence interval [CI], 72 to 89; P<0.001 for the comparison with a 20% historical control rate); among these patients, the complete response rate was 52% (Table S1 in the Supplementary Appendix). An additional 9 patients were enrolled and awaiting treatment at the time that the 92nd patient received the axi-cel infusion. Among the 101 patients who received axi-cel, the objective response rate was 82% (95% CI, 73 to 89), with a 54% complete response rate (Figure 1A, and Fig. S2 in the Supplementary Appendix).

The median time to response was rapid (1.0 month; range, 0.8 to 6.0). The median duration of response was 8.1 months (95% CI, 3.3 to could not be estimated). Response rates were consistent across key covariates, including age, disease stage, International Prognostic Index score at enrollment, presence or absence of bulky disease, cell-of-origin subtype, and use of tocilizumab or glucocorticoids. Responses were also consistent in 26 patients who had a history of primary refractory disease (response rate, 88%) and in 21 patients who had a history of autologous stem-cell transplantation (response rate, 76%). The response rates did not appear to be influenced by biologic covariates, such as the prevalence and intensity of CD19 expression, or by product characteristics, such as the ratio of CD4 cells to CD8 cells and T-cell phenotypes (Figure 1B, and Tables S2, S3, and S4 in the Supplementary Appendix).

At the time of the primary analysis, 52 patients had disease progression, 3 patients had died from adverse events during treatment, 1 patient started an alternative therapy before disease progression, 44 remained in remission (of whom 39 had a complete response), and 1 had stable disease. Of the patients who had disease progression after an initial response, 9 were retreated with axi-cel, according to the protocol. Of these patients, 5 had a response (2 complete and 3 partial), and 2 of these patients had an ongoing response.

Updated Analysis

To evaluate the durability of response with axi-cel, we performed an updated analysis when the 108 patients in the phase 1 and 2 portions of ZUMA-1 had been followed for a minimum of 1 year. The objective response rate was 82%, including a complete response rate of 58%. Of the patients who did not have a complete response at the time of the first tumor assessment (1 month after the infusion of axi-cel), 23 patients (11 of 35 with a partial response and 12 of 25 with stable disease) subsequently had a complete response in the absence of additional therapies as late as 15 months after treatment. At the data cutoff, 42% remained in response, including 40% with a complete response. Of the 7 patients in phase 1 of the study, 3 had an ongoing complete response at 24 months.

Preliminary analysis of CD19 expression at baseline and at the time of disease progression was ongoing. Of the 11 patients with disease progression who were included in the analysis, 3 (27%) with CD19-positive status at baseline had CD19-negative disease at time of disease progression.

Figure 2. Figure 2. Kaplan–Meier Estimates of the Duration of Response, Progression-free Survival, and Overall Survival.

Panel A shows the duration of response, according to investigator assessment, in the 89 study patients who had an objective response, including those with a complete response and those with a partial response. Patients who had a complete response had a longer duration of response than those with an objective or partial response. According to independent central review, the median duration of response was 8.1 months (range, 3.5 to could not be estimated [NE]). Panel B shows the rate of progression-free survival, and Panel C the rate of overall survival in the 108 patients who were treated in the phase 1 and phase 2 studies. Tick marks indicate the time of data censoring at the last follow-up. NR denotes not reached.

Ongoing response rates were consistent across key covariates, including the use of tocilizumab or glucocorticoids (Fig. S3 in the Supplementary Appendix). The median duration of response was 11.1 months (95% CI, 3.9 to could not be estimated) (Figure 2A). The median duration of progression-free survival was 5.8 months (95% CI, 3.3 to could not be estimated) (Figure 2B), with progression-free survival rates of 49% (95% CI, 39 to 58) at 6 months, 44% (95% CI, 34 to 53) at 12 months, and 41% (95% CI, 31 to 50) at 15 months. The median overall survival was not yet reached (95% CI, 12.0 months to could not be estimated) (Figure 2C), with overall survival rates of 78% (95% CI, 69 to 85) at 6 months, 59% (95% CI, 49 to 68) at 12 months, and 52% (95% CI, 41 to 62) at 18 months. A total of 56% of patients remained alive at the time of the data cutoff. Two patients who had a response underwent allogeneic stem-cell transplantation.

Safety

Primary Analysis

Table 2. Table 2. Adverse Events, the Cytokine Release Syndrome, and Neurologic Events Associated with Treatment.

During treatment, all 101 patients who had received axi-cel had adverse events, which were grade 3 or higher in 95% (Table 2). The most common adverse events of any grade were pyrexia (in 85% of the patients), neutropenia (in 84%), and anemia (in 66%). The most common adverse events of grade 3 or higher were neutropenia (in 78%), anemia (in 43%), and thrombocytopenia (in 38%). The cytokine release syndrome occurred in 94 patients (93%). Most cases were of low grade (37% of grade 1 and 44% of grade 2), with 13% of grade 3 or higher (9% of grade 3, 3% of grade 4, and 1% of grade 5).

The most common symptoms of the cytokine release syndrome of grade 3 or higher were pyrexia (in 11% of the patients), hypoxia (in 9%), and hypotension (in 9%). Vasopressors were used in 17% of the patients. The median time after infusion until the onset of the cytokine release syndrome was 2 days (range, 1 to 12), and the median time until resolution was 8 days. All the events associated with the cytokine release syndrome resolved except for one event of grade 5 hemophagocytic lymphohistiocytosis. Another event of grade 5 cardiac arrest occurred in a patient with the cytokine release syndrome.

Neurologic events occurred in 65 patients (64%); 28% were grade 3 or higher. The most common neurologic events of grade 3 or higher were encephalopathy (in 21% of the patients), confusional state (in 9%), aphasia (in 7%), and somnolence (in 7%). Early neurologic signs included word-finding difficulties (dysphasia), attention or calculation defects (counting backward by serial 7s), and difficulty executing complex commands (handwriting).27 The median onset of neurologic events occurred on day 5 (range, 1 to 17), with median resolution on day 17 after infusion. One patient had ongoing grade 1 memory impairment that resolved after the data cutoff for the primary analysis. All the other neurologic events resolved except for four events, which were ongoing at the time of death (two deaths from progressive disease and two from adverse events unrelated to neurologic events). Rates of the cytokine release syndrome and neurologic events decreased over the course of the study (Table S5 in the Supplementary Appendix). Forty-three percent of patients received tocilizumab and 27% received glucocorticoids for the management of the cytokine release syndrome, neurologic events, or both,24 with no apparent effect on overall or ongoing response rates (Figure 1B, and Fig. S3 in the Supplementary Appendix).

Updated Analysis

Ten patients had serious adverse events (including nine infections in 8 patients) after the data cutoff for the primary analysis (Table S6 in the Supplementary Appendix). There were no new events associated with the cytokine release syndrome or neurologic events related to axi-cel treatment. Forty-four patients (44%) died from causes that included disease progression (in 37 patients), adverse events (in 3 patients, including 2 with the above-mentioned axi-cel–related events associated with the cytokine release syndrome and 1 with pulmonary embolism that was not related to axi-cel), and other causes after disease progression and subsequent therapies that were not related to axi-cel (in 4). One death that was not associated with axi-cel was previously reported in phase 1 of ZUMA-1.21 There were no new deaths from adverse events after the primary analysis. No cases of replication-competent retrovirus or axi-cel treatment-related secondary cancers were reported.

Biomarkers

Figure 3. Figure 3. CAR T-Cell Expansion and Correlations with Response and Adverse Events.

Serial blood samples were analyzed for chimeric antigen receptor (CAR) T-cell levels and serum biomarkers in all 101 patients who were treated with axi-cel, as described previously.21 Panel A shows CAR T-cell expansion and persistence with median values and interquartile ranges (Q1 and Q3). Panel B shows the association between CAR T-cell expansion, which was measured as peak levels of CAR cells per microliter of blood, and the objective response rate, neurologic events, and the cytokine release syndrome. The peak factor change is shown for patients with a response as compared with those without a response, for those with neurologic events of grade 3 or higher, and for those with the cytokine release syndrome of grade 3 or higher. P values were calculated by means of the Wilcoxon rank-sum test. Panel C shows serum biomarkers (interleukin-2, granulocyte–macrophage colony-stimulating factor [GM-CSF], and ferritin) that were associated only with neurologic events and not with the cytokine release syndrome. The peak value is defined as the maximum level of the cytokine after baseline. The peak factor is the value in patients with neurologic events of grade 3 or higher versus those with events of grade 0 to 2. Adjusted P values were calculated with the use of Holm’s procedure after multiple testing by means of the Wilcoxon rank-sum test. In Panels B and C, the horizontal line within each box represents the median, and the lower and upper borders of each box represent the 25th and the 75th percentiles, respectively, and the I bars represent the minimum and maximum range.

CAR T levels peaked in the peripheral blood within 14 days after infusion of axi-cel and were detectable in most patients at 180 days after infusion (Figure 3A). Three patients with ongoing complete remission at 24 months still had detectable CAR T levels in the blood. Expansion was significantly associated with response (P<0.001), with an area under the curve within the first 28 days after treatment that was 5.4 times as high among the patients who had a response as among those who did not have a response. Peak expansion and area under the curve were significantly associated with neurologic events of grade 3 or higher but not with the cytokine release syndrome (Figure 3B, and Table S7 and Fig. S4 in the Supplementary Appendix). Of 44 serum biomarkers that were examined, several biomarkers, including interleukin-6, -10, -15, and -2Rα and granzyme B, were significantly associated with neurologic events and the cytokine release syndrome of grade 3 or higher (Table S8 in the Supplementary Appendix). Several biomarkers, including interleukin-2, granulocyte–macrophage colony-stimulating factor (GM-CSF), and ferritin, were significantly associated only with neurologic events of grade 3 or higher (Figure 3C). The induction of anti-CAR antibodies was not observed in any patient.

Discussion

In this multicenter, phase 2 trial of axi-cel therapy, 82% of the 101 patients with refractory large B-cell lymphoma who were treated had an objective response, and 54% had a complete response. These findings compare favorably with the results of the recent SCHOLAR-1 study of existing therapies for this disease, which showed an objective response rate of 26% and a complete response rate of 7%.14 With a median follow-up of 15.4 months in our study, responses were ongoing in 42% of the patients, including in 40% who had a complete response, with the emergence of a plateau in the duration of the response curve at 6 months. Although most responses occurred in the first month, 23 patients had a complete response as late as 15 months. It would be reasonable to monitor patients who did not have a complete response at the first disease assessment and allow for an opportunity for an improved response, since consolidation with allogeneic stem-cell transplantation comes with a high rate of treatment-related death and would also ablate CAR T cells. The median overall survival had not been reached, with an overall survival rate at 18 months of 52%. Ongoing durable remissions have been observed in patients at 24 months. These results, combined with the observation of ongoing long-term remissions beyond 4 years in the previous National Cancer Institute study,17 suggest that axi-cel provides substantial clinical benefit for patients with refractory disease.

In our study, the responses to treatment, including ongoing ones, were consistent across key covariates. Similar response rates were observed in the 8 patients with CD19-negative disease as in those with CD19-positive disease at baseline, which suggests the potential limitations in CD19 detection rather than true CD19 negativity. Analyses of product characteristics, including the ratio of CD4 cells to CD8 cells and T-cell phenotypes, also showed similar outcomes, which further highlights the consistency in treatment effects across clinical and biologic covariates. One limitation of our study is the lack of a planned, detailed analysis of molecular and cytogenetic characteristics. Prospective data are needed on the influence of disease biology, such as double- and triple-hit lymphomas, on outcomes with CAR T-cell therapy.

To be successful, a personalized cell therapy must be delivered in a safe and timely manner. In this study, we confirmed the feasibility and reliability of centralized manufacturing and coordination of leukapheresis procedures and shipping from multiple centers across the country. The product was manufactured for 99% of the enrolled patients and was administered to 91%. The short 17-day median turnaround time was critical for these patients with refractory large B-cell lymphoma, who generally have rapidly growing disease.

We found that axi-cel could be administered safely at medical facilities that perform transplantation, even if such centers had no experience in CAR T-cell therapy. Algorithms for the management of the cytokine release syndrome and neurologic events were effectively implemented. The incidence of the cytokine release syndrome and neurologic events of grade 3 or higher decreased over the course of the study, possibly because of increased experience at the study centers and a protocol amendment allowing for earlier administration of tocilizumab or glucocorticoids.27 The cytokine release syndrome and neurologic events were generally reversible with no clinical sequelae. With extended follow-up, there were no new unexpected serious adverse events and no new onset of the cytokine release syndrome or neurologic events related to CAR T cells. Furthermore, the 3% rate of death during treatment compares favorably with rates observed during allogeneic stem-cell transplantation.28

CAR T-cell levels over the first 28 days of treatment correlated with an objective response. This finding was consistent with prior single-institution trials of CAR T-cell therapy19,25 and strengthens the hypothesis that the presence of higher CAR T-cell levels after infusion may further augment efficacy. Recent studies have shown intrinsic differences in CAR T cells that use CD28 rather than other costimulatory molecules, such as 4-1BB,29,30 but it remains unclear whether either costimulatory domain will confer differences in activity or persistence in patients and whether such responses are dependent on the tumor type.31 Therefore, optimization of CAR constructs and manufacturing as well as combination strategies with immunomodulatory agents are being explored.

Serum biomarker analysis confirmed associations of the presence of interleukin-6, -15, and -2Rα, as well as other markers, with the cytokine release syndrome of grade 3 or higher19,32-35 and with neurologic events of grade 3 or higher.19,34 However, CAR T-cell levels and specific cytokines, including interleukin-2, GM-CSF, and ferritin, were associated only with grade 3 or higher neurologic events, which suggests that distinct mechanisms may underlie the pathogenesis of these adverse events.

Although there is a theoretical concern regarding the use of immunosuppressive agents to manage the cytokine release syndrome or neurologic events, the use of tocilizumab or glucocorticoids did not appear to affect the overall response among the patients in our study. Furthermore, the development of a predictive or prognostic early biomarker of the cytokine release syndrome or neurologic events may assist clinicians in determining when to intervene and optimize the management of toxic effects while preserving efficacy.

In conclusion, our findings support the use of axi-cel as an effective therapeutic option in adult patients with relapsed or refractory large B-cell lymphoma after at least two prior systemic therapies. Adverse events included myelosuppression, the cytokine release syndrome, and neurologic events.

Funding and Disclosures

Supported by Kite Pharma and the Leukemia and Lymphoma Society Therapy Acceleration Program.

Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.

Dr. Neelapu reports receiving advisory board fees from Kite Pharma; Dr. Locke, receiving consulting fees from Cellular Biomedicine Group and scientific advisory fees from Kite Pharma; Dr. Bartlett, receiving grant support from Celgene, Genentech, Merck, Bristol-Myers Squibb, Immune Design, Forty Seven, Affimed, Janssen, Pharmacyclics, Millennium, ImaginAb, Novartis, Gilead, Dynavax, Medimmune, Incyte, and Idera and grant support and advisory board fees from Seattle Genetics, Pfizer, and Kite Pharma; Dr. Miklos, receiving grant support and advisory board fees from Kite Pharma, Pharmacyclics, Adaptive Biotechnologies, Novartis, and Janssen; Dr. Jacobson, receiving consulting fees from Kite Pharma; Dr. Braunschweig, receiving lecture fees from Kite Pharma; Dr. Siddiqi, receiving grant support and lecture fees from Pharmacyclics, lecture fees from Seattle Genetics, and grant support and fees for serving on a steering committee from Juno; Dr. Timmerman, receiving grant support from Bristol-Myers Squibb, Valor Biopharmaceuticals, and Janssen and consulting fees from Celgene, Seattle Genetics, and Genmab; Dr. Friedberg, receiving fees for serving on an advisory board from Bayer; Dr. Flinn, receiving grant support from Acerta, Agios, ArQule, BeiGene, Calithera, Constellation, Forty Seven, Genentech, Gilead, Infinity, Janssen, Kite Pharma, Merck, Novartis, Pharmacyclics, Seattle Genetics, TG Therapeutics, Trillium Therapeutics, and Verastem; Dr. Goy, receiving grant support, paid to his institution, consulting fees, and honoraria from Celgene and Pharmacyclics, grant support, paid to his institution, and honoraria from Acerta, grant support, paid to his institution, and consulting fees from Genentech, and honoraria from Takeda; Dr. Smith, receiving grant support and consulting fees from Seattle Genetics, consulting fees from Genentech, and grant support from Takeda and Celgene; Dr. Farooq, receiving grant support from Kite Pharma; Dr. McSweeney, receiving advisory board fees and lecture fees from Kite Pharma; Dr. Munoz, serving on advisory boards for Pfizer, Pharmacyclics, Alexion, and Bayer; Dr. Chavez, receiving lecture fees from Kite Pharma and advisory board fees from Novartis; Dr. Ghobadi, lecture fees from Kite Pharma; Dr. Levy, receiving consulting fees from Five Prime, BeiGene, Innate Pharma, Immune Design, and Corvus and grant support from Bristol-Myers Squibb, Pfizer, Pharmacyclics, and Dynavax; Dr. Jacobsen, receiving consulting fees from Bayer, Merck, Seattle Genetics, Spectrum, and Pharmacyclics; Dr. Reagan, receiving grant support from Seattle Genetics; Drs. Bot, Jiang, Chang, Wiezorek, and Go, Mr. Rossi, Ms. Navale, Mr. Aycock, and Ms. Elias, being employed by Kite Pharma; Drs. Jiang and Wiezorek, Mr. Aycock, and Ms. Elias, having an equity interest in Kite Pharma; Mr. Rossi, Ms. Navale, and Dr. Go, having an equity interest in Gilead Sciences; and Dr. Chang, having an equity interest in Gilead Sciences, Cell Design Lab, and UroGen. No other potential conflict of interest relevant to this article was reported.

Drs. Neelapu and Locke contributed equally to this article.

This article was published on December 10, 2017, at NEJM.org.

We thank the patients who participated in the study and their families, friends, and caregivers; the study staff and health care providers at all the study sites; and Dustin Khiem of Kite Pharma and Skye Geherin and Jennifer Leslie of Nexus Global Group Science for medical writing.

Author Affiliations

From the University of Texas M.D. Anderson Cancer Center, Houston (S.S.N., J.R.W.); H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (F.L.L., J.C.C.); Washington University and Siteman Cancer Center, St. Louis (N.L.B., A. Ghobadi); University of Miami, Miami (L.J.L., K.V.K.); Stanford University, Stanford (D.B.M., R.L.), City of Hope National Medical Center, Duarte (T.S.), University of California at Los Angeles, Los Angeles (J.M.T.), University of California at San Diego, San Diego (J.E.C.), and Kite Pharma, Santa Monica (A.B., J.R., L.N., Y.J., J.A., M.E., D.C., J.W., W.Y.G.) — all in California; Dana–Farber Cancer Institute, Boston (C.A.J., E.D.J.); Montefiore Medical Center, Bronx (I.B.), and the University of Rochester School of Medicine, Rochester (J.W.F., P.R.) — both in New York; Vanderbilt University Medical Center (O.O.O.) and the Sarah Cannon Research Institute and Tennessee Oncology (I.W.F.), Nashville; Mayo Clinic, Rochester, MN (Y.L., T.E.W.); Loyola University Medical Center, Maywood, IL (P.J.S.); John Theurer Cancer Center, Hackensack University Medical Center, Hackensack, NJ (A. Goy); Cleveland Clinic, Cleveland (B.T.H., M.R.S.); Karmanos Cancer Center, Wayne State University, Detroit (A.D.); University of Iowa Carver College of Medicine, Iowa City (U.F.); Colorado Blood Cancer Institute, Denver (P.M.S.); Banner M.D. Anderson Cancer Center, Gilbert, AZ (J.M.); and Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel (I.A.).

Address reprint requests to Dr. Neelapu at the University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, or at .

Supplementary Material

References (35)

  1. 1. Sehn LH, Gascoyne RD. Diffuse large B-cell lymphoma: optimizing outcome in the context of clinical and biologic heterogeneity. Blood 2015;125:22-32

  2. 2. Dunleavy K, Wilson WH. Primary mediastinal B-cell lymphoma and mediastinal gray zone lymphoma: do they require a unique therapeutic approach? Blood 2015;125:33-39

  3. 3. Casulo C, Burack WR, Friedberg JW. Transformed follicular non-Hodgkin lymphoma. Blood 2015;125:40-47

  4. 4. Ardeshna KM, Kakouros N, Qian W, et al. Conventional second-line salvage chemotherapy regimens are not warranted in patients with malignant lymphomas who have progressive disease after first-line salvage therapy regimens. Br J Haematol 2005;130:363-372

  5. 5. Hitz F, Connors JM, Gascoyne RD, et al. Outcome of patients with primary refractory diffuse large B cell lymphoma after R-CHOP treatment. Ann Hematol 2015;94:1839-1843

  6. 6. Josting A, Reiser M, Rueffer U, Salzberger B, Diehl V, Engert A. Treatment of primary progressive Hodgkin’s and aggressive non-Hodgkin’s lymphoma: is there a chance for cure? J Clin Oncol 2000;18:332-339

  7. 7. Matasar MJ, Czuczman MS, Rodriguez MA, et al. Ofatumumab in combination with ICE or DHAP chemotherapy in relapsed or refractory intermediate grade B-cell lymphoma. Blood 2013;122:499-506

  8. 8. Moskowitz CH, Bertino JR, Glassman JR, et al. Ifosfamide, carboplatin, and etoposide: a highly effective cytoreduction and peripheral-blood progenitor-cell mobilization regimen for transplant-eligible patients with non-Hodgkin’s lymphoma. J Clin Oncol 1999;17:3776-3785

  9. 9. Nagle SJ, Woo K, Schuster SJ, et al. Outcomes of patients with relapsed/refractory diffuse large B-cell lymphoma with progression of lymphoma after autologous stem cell transplantation in the rituximab era. Am J Hematol 2013;88:890-894

  10. 10. Philip T, Guglielmi C, Hagenbeek A, et al. Autologous bone marrow transplantation as compared with salvage chemotherapy in relapses of chemotherapy-sensitive non-Hodgkin’s lymphoma. N Engl J Med 1995;333:1540-1545

  11. 11. Seshadri T, Stakiw J, Pintilie M, Keating A, Crump M, Kuruvilla J. Utility of subsequent conventional dose chemotherapy in relapsed/refractory transplant-eligible patients with diffuse large B-cell lymphoma failing platinum-based salvage chemotherapy. Hematology 2008;13:261-266

  12. 12. Telio D, Fernandes K, Ma C, et al. Salvage chemotherapy and autologous stem cell transplant in primary refractory diffuse large B-cell lymphoma: outcomes and prognostic factors. Leuk Lymphoma 2012;53:836-841

  13. 13. Friedberg JW. Relapsed/refractory diffuse large B-cell lymphoma. Hematology Am Soc Hematol Educ Program 2011;2011:498-505

  14. 14. Crump M, Neelapu SS, Farooq U, et al. Outcomes in refractory diffuse large B-cell lymphoma: results from the international SCHOLAR-1 study. Blood 2017;130:1800-1808

  15. 15. Kochenderfer JN, Dudley ME, Feldman SA, et al. B-cell depletion and remissions of malignancy along with cytokine-associated toxicity in a clinical trial of anti-CD19 chimeric-antigen-receptor-transduced T cells. Blood 2012;119:2709-2720

  16. 16. Kochenderfer JN, Dudley ME, Kassim SH, et al. Chemotherapy-refractory diffuse large B-cell lymphoma and indolent B-cell malignancies can be effectively treated with autologous T cells expressing an anti-CD19 chimeric antigen receptor. J Clin Oncol 2015;33:540-549

  17. 17. Kochenderfer JN, Somerville RPT, Lu T, et al. Long-duration complete remissions of diffuse large B cell lymphoma after anti-CD19 chimeric antigen receptor T cell therapy. Mol Ther 2017;25:2245-2253

  18. 18. Schuster S, Svoboda J, Nasta S, et al. Sustained remissions following chimeric antigen receptor modified T cells directed against CD19 (CTL019) in patients with relapsed or refractory CD19+ lymphomas. Blood 2015;126:183-183

  19. 19. Turtle CJ, Hanafi LA, 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;8:355ra116-355ra116

  20. 20. Kochenderfer JN, Feldman SA, Zhao Y, et al. Construction and preclinical evaluation of an anti-CD19 chimeric antigen receptor. J Immunother 2009;32:689-702

  21. 21. Locke FL, Neelapu SS, Bartlett NL, et al. Phase 1 results of ZUMA-1: a multicenter study of KTE-C19 anti-CD19 CAR T cell therapy in refractory aggressive lymphoma. Mol Ther 2017;25:285-295

  22. 22. WHO classification of tumours of haematopoietic and lymphoid tissue. 4th ed. Geneva: World Health Organization, 2008.

  23. 23. Cheson BD, Pfistner B, Juweid ME, et al. Revised response criteria for malignant lymphoma. J Clin Oncol 2007;25:579-586

  24. 24. Lee DW, Gardner R, Porter DL, et al. Current concepts in the diagnosis and management of cytokine release syndrome. Blood 2014;124:188-195

  25. 25. Kochenderfer JN, Somerville RPT, Lu T, et al. Lymphoma remissions caused by anti-CD19 chimeric antigen receptor T cells are associated with high serum interleukin-15 levels. J Clin Oncol 2017;35:1803-1813

  26. 26. Scott DW, Wright GW, Williams PM, et al. Determining cell-of-origin subtypes of diffuse large B-cell lymphoma using gene expression in formalin-fixed paraffin-embedded tissue. Blood 2014;123:1214-1217

  27. 27. Neelapu SS, Tummala S, Kebriaei P, et al. Chimeric antigen receptor T-cell therapy — assessment and management of toxicities. Nat Rev Clin Oncol 2017 September 19 (Epub ahead of print)

  28. 28. Klyuchnikov E, Bacher U, Kroll T, et al. Allogeneic hematopoietic cell transplantation for diffuse large B cell lymphoma: who, when and how? Bone Marrow Transplant 2014;49:1-7

  29. 29. Kawalekar OU, O’Connor RS, Fraietta JA, et al. Distinct signaling of coreceptors regulates specific metabolism pathways and impacts memory development in CAR T cells. Immunity 2016;44:380-390

  30. 30. Zhao Z, Condomines M, van der Stegen SJC, et al. Structural design of engineered costimulation determines tumor rejection kinetics and persistence of CAR T cells. Cancer Cell 2015;28:415-428

  31. 31. Park JH, Brentjens RJ. Are all chimeric antigen receptors created equal? J Clin Oncol 2015;33:651-653

  32. 32. Maude SL, Frey N, Shaw PA, et al. Chimeric antigen receptor T cells for sustained remissions in leukemia. N Engl J Med 2014;371:1507-1517

  33. 33. Davila ML, Riviere I, Wang X, et al. Efficacy and toxicity management of 19-28z CAR T cell therapy in B cell acute lymphoblastic leukemia. Sci Transl Med 2014;6:224ra25-224ra25

  34. 34. Turtle CJ, Hanafi LA, Berger C, et al. CD19 CAR-T cells of defined CD4+:CD8+ composition in adult B cell ALL patients. J Clin Invest 2016;126:2123-2138

  35. 35. Teachey DT, Lacey SF, Shaw PA, et al. Identification of predictive biomarkers for cytokine release syndrome after chimeric antigen receptor T-cell therapy for acute lymphoblastic leukemia. Cancer Discov 2016;6:664-679

Citing Articles (2052)

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    Letters

    Figures/Media

    1. Table 1. Treatment Disposition and Baseline Characteristics of the Patients.
      Table 1. Treatment Disposition and Baseline Characteristics of the Patients.
    2. Figure 1. Objective Response Rate among the 101 Treated Patients.
      Figure 1. Objective Response Rate among the 101 Treated Patients.

      Panel A shows the objective response rate (ORR; calculated as complete response [CR] plus partial response [PR]) among the patients who received axicabtagene ciloleucel (axi-cel), an anti-CD19 chimeric antigen receptor T-cell therapy, as well as the response among the patients with stable disease (SD), disease progression (PD), and those who could not be evaluated (NE). The patients in the modified intention-to-treat population were evaluated according to the two main disease cohorts: diffuse large B-cell lymphoma (DLBCL) and either primary mediastinal large B-cell lymphoma (PMBCL) or transformed follicular lymphoma (TLF). The numbers in parentheses indicate the number of patients who had the specified response. On independent central review, the objective response rate was 71%, including a complete response rate of 51% and a partial response rate of 20%. Panel B shows the subgroup analysis of the objective response rate for key baseline and clinical covariates. Scores on the International Prognostic Index (IPI) include low risk (0 or 1 point), low-intermediate risk (2 points), high-intermediate risk (3 points), and high risk (4 or 5 points). The 95% confidence interval (CI) was calculated with the use of the Clopper–Pearson method. ASCT denotes autologous stem-cell transplantation.

    3. Figure 2. Kaplan–Meier Estimates of the Duration of Response, Progression-free Survival, and Overall Survival.
      Figure 2. Kaplan–Meier Estimates of the Duration of Response, Progression-free Survival, and Overall Survival.

      Panel A shows the duration of response, according to investigator assessment, in the 89 study patients who had an objective response, including those with a complete response and those with a partial response. Patients who had a complete response had a longer duration of response than those with an objective or partial response. According to independent central review, the median duration of response was 8.1 months (range, 3.5 to could not be estimated [NE]). Panel B shows the rate of progression-free survival, and Panel C the rate of overall survival in the 108 patients who were treated in the phase 1 and phase 2 studies. Tick marks indicate the time of data censoring at the last follow-up. NR denotes not reached.

    4. Table 2. Adverse Events, the Cytokine Release Syndrome, and Neurologic Events Associated with Treatment.
      Table 2. Adverse Events, the Cytokine Release Syndrome, and Neurologic Events Associated with Treatment.
    5. Figure 3. CAR T-Cell Expansion and Correlations with Response and Adverse Events.
      Figure 3. CAR T-Cell Expansion and Correlations with Response and Adverse Events.

      Serial blood samples were analyzed for chimeric antigen receptor (CAR) T-cell levels and serum biomarkers in all 101 patients who were treated with axi-cel, as described previously.21 Panel A shows CAR T-cell expansion and persistence with median values and interquartile ranges (Q1 and Q3). Panel B shows the association between CAR T-cell expansion, which was measured as peak levels of CAR cells per microliter of blood, and the objective response rate, neurologic events, and the cytokine release syndrome. The peak factor change is shown for patients with a response as compared with those without a response, for those with neurologic events of grade 3 or higher, and for those with the cytokine release syndrome of grade 3 or higher. P values were calculated by means of the Wilcoxon rank-sum test. Panel C shows serum biomarkers (interleukin-2, granulocyte–macrophage colony-stimulating factor [GM-CSF], and ferritin) that were associated only with neurologic events and not with the cytokine release syndrome. The peak value is defined as the maximum level of the cytokine after baseline. The peak factor is the value in patients with neurologic events of grade 3 or higher versus those with events of grade 0 to 2. Adjusted P values were calculated with the use of Holm’s procedure after multiple testing by means of the Wilcoxon rank-sum test. In Panels B and C, the horizontal line within each box represents the median, and the lower and upper borders of each box represent the 25th and the 75th percentiles, respectively, and the I bars represent the minimum and maximum range.