Project description:Chimeric antigen receptor (CAR) T cells targeting CD19 have achieved breakthroughs in the treatment of hematological malignancies, such as relapsed/refractory non-Hodgkin lymphoma (r/rNHL); however, high rates of treatment failure and recurrence after CAR T-cell therapy are considerable obstacles to overcome. In this study, we designed a series of tandem CARs (TanCARs) and found that TanCAR7 T cells showed dual antigen targeting of CD19 and CD20, as well as formed superior and stable immunological synapse (IS) structures, which may be related to their robust antitumor activity. In an open-label single-arm phase 1/2a trial (NCT03097770), we enrolled 33 patients with r/rNHL; 28 patients received an infusion after conditioning chemotherapy. The primary objective was to evaluate the safety and tolerability of TanCAR7 T cells. Efficacy, progression-free survival, and overall survival were evaluated as secondary objectives. Cytokine release syndrome occurred in 14 patients (50%): 36% had grade 1 or 2 and 14% had grade 3. No cases of CAR T-cell-related encephalopathy syndrome (CRES) of grade 3 or higher were confirmed in any patient. One patient died from a treatment-associated severe pulmonary infection. The overall response rate was 79% (95% confidence interval [CI], 60-92%), and the complete response rate was 71%. The progression-free survival rate at 12 months was 64% (95% CI, 43-79%). In this study, TanCAR7 T cells elicited a potent and durable antitumor response, but not grade 3 or higher CRES, in patients with r/rNHL.
Project description:Increasing the remission rate and reducing the recurrence rate can improve the clinical efficacy of chimeric antigen receptor (CAR) T cell therapy in recurrent/refractory non-Hodgkin lymphoma (r/rNHL). In this open-label, single-arm phase I/II trial, 87 patients with r/rNHL, including 58 patients with aggressive diffuse large B-cell lymphoma and 24 with high tumour burden, received an infusion at doses of 0.5 × 106-8 × 106 TanCAR7 T cells per kilogram of body weight after conditioning chemotherapy. The best overall response rate was 78% (95% confidence interval [CI], 68-86); response rates were consistent across prognostic subgroups. The median follow-up was 27.7 months. The median progression-free survival was 27.6 months (95% CI, 11 to not reached). Cytokine release syndrome (CRS) occurred in 61 patients (70%) with 60% of cases being grade 1 or 2 and 10% being grade 3 or greater. Grade 3 CAR T cell-related encephalopathy syndrome (CRES) occurred in 2 patients (2%). Two patients died from treatment-associated severe pulmonary infection, and one died from CRS-related pulmonary injury between 1 and 3 months post infusion. Long-term remissions were observed following the use of TanCAR7 T cells in r/rNHL with a safety profile that included CRS but few cases of CRES.
Project description:To address antigen escape and loss of T-cell functionality, we report a phase I clinical trial (NCT04007029) evaluating autologous naive and memory T (TN/MEM) cells engineered to express a bispecific anti-CD19/CD20 chimeric antigen receptor (CAR; CART19/20) for patients with relapsed/refractory non-Hodgkin lymphoma (NHL), with safety as the primary endpoint. Ten patients were treated with 36 × 106 to 165 × 106 CART19/20 cells. No patient experienced neurotoxicity of any grade or over grade 1 cytokine release syndrome. One case of dose-limiting toxicity (persistent cytopenia) was observed. Nine of 10 patients achieved objective response [90% overall response rate (ORR)], with seven achieving complete remission [70% complete responses (CR) rate]. One patient relapsed after 18 months in CR but returned to CR after receiving a second dose of CART19/20 cells. Median progression-free survival was 18 months and median overall survival was not reached with a 17-month median follow-up. In conclusion, CART19/20 TN/MEM cells are safe and effective in patients with relapsed/refractory NHL, with durable responses achieved at low dosage levels.SignificanceAutologous CD19/CD20 bispecific CAR-T cell therapy generated from TN/MEM cells for patients with NHL is safe (no neurotoxicity, maximum grade 1 cytokine release syndrome) and demonstrates strong efficacy (90% ORR, 70% CR rate) in a first-in-human, phase I dose-escalation trial. This article is highlighted in the In This Issue feature, p. 517.
Project description:AbstractCD19 chimeric antigen receptor (CAR) T-cell therapy has proven highly effective for treating relapsed/refractory mantle cell lymphoma (MCL). However, immune effector cell-associated neurotoxicity syndrome (ICANS) remains a significant concern. This study aimed to evaluate the clinical, radiological, and laboratory correlatives associated with ICANS development after CD19 CAR T-cell therapy in patients with MCL. All patients (N = 26) who received standard-of-care brexucabtagene autoleucel until July 2022 at our institution were evaluated. Laboratory and radiographic correlatives including brain magnetic resonance imaging (MRI) and electroencephalogram (EEG) were evaluated to determine the clinical impact of ICANS. Seventeen (65%) patients experienced ICANS after treatment, with a median onset on day 6. Ten (38%) patients experienced severe (grade ≥3) ICANS. All patients with ICANS had antecedent cytokine release syndrome (CRS), but no correlation was observed between ICANS severity and CRS grade. Overall, 92% of EEGs revealed interictal changes; no patients experienced frank seizures because of ICANS. In total, 86% of patients with severe ICANS with postinfusion brain MRIs demonstrated acute neuroimaging findings not seen on pretreatment MRI. Severe ICANS was also associated with higher rates of cytopenia, coagulopathy, increased cumulative steroid exposure, and prolonged hospitalization. However, severe ICANS did not affect treatment outcomes of patients with MCL. Severe ICANS is frequently associated with a range of postinfusion brain MRI changes and abnormal EEG findings. Longer hospitalization was observed in patients with severe ICANS, especially those with abnormal acute MRI or EEG findings, but there was no discernible impact on overall treatment response and survival.
Project description:ABSTRACT B cell lymphoma therapy has been transformed by CD19-targeting cellular therapeutics that induce high clinical response rates and impressive remissions in relapsed and refractory patients. However, approximately half of all patients who respond to CD19-directed cell therapy relapse, the majority within 6 months. One characteristic of relapse is loss or reduction of CD19 expression on malignant B cells. We designed a unique therapeutic to prevent and reverse relapses due to lost or reduced CD19 expression. This novel biologic, a CAR T Engager, binds CD20 and displays the CD19 extracellular domain. This approach increases the apparent CD19 antigen density on CD19-positive/CD20-positive lymphoma cells, and prevents antigen-loss induced relapse, as CD19 bound to CD20 remains present on the cell surface. We demonstrate that this novel therapeutic prevents and reverses lymphoma relapse in vitro and prevents CD19-negative lymphoma growth and relapse in vivo.
Project description:Outcomes for patients with refractory diffuse large B cell lymphoma (DLBCL) are poor. In the multicenter ZUMA-1 phase 1 study, we evaluated KTE-C19, an autologous CD3ζ/CD28-based chimeric antigen receptor (CAR) T cell therapy, in patients with refractory DLBCL. Patients received low-dose conditioning chemotherapy with concurrent cyclophosphamide (500 mg/m2) and fludarabine (30 mg/m2) for 3 days followed by KTE-C19 at a target dose of 2 × 106 CAR T cells/kg. The incidence of dose-limiting toxicity (DLT) was the primary endpoint. Seven patients were treated with KTE-C19 and one patient experienced a DLT of grade 4 cytokine release syndrome (CRS) and neurotoxicity. Grade ≥3 CRS and neurotoxicity were observed in 14% (n = 1/7) and 57% (n = 4/7) of patients, respectively. All other KTE-C19-related grade ≥3 events resolved within 1 month. The overall response rate was 71% (n = 5/7) and complete response (CR) rate was 57% (n = 4/7). Three patients have ongoing CR (all at 12+ months). CAR T cells demonstrated peak expansion within 2 weeks and continued to be detectable at 12+ months in patients with ongoing CR. This regimen of KTE-C19 was safe for further study in phase 2 and induced durable remissions in patients with refractory DLBCL.
Project description:We examined whether a pretargeting method using a new recombinant anti-CD20 bispecific antibody (bsMAb) followed by (90)Y-1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid ((90)Y-DOTA)-peptide could reduce hematologic toxicity yet improve therapeutic responses compared with conventional (90)Y-anti-CD20 IgG and a chemically conjugated bsMAb. TF4, a humanized, tri-Fab bsMAb with two Fabs binding CD20 and one Fab binding histamine-succinyl-glycine (HSG), developed by the dock and lock (DNL) method, was tested in nude mice with Ramos B-cell lymphomas. Optimal pretargeting required a 29-h interval between TF4 and (90)Y-DOTA-HSG, and 20-fold more moles of TF4. TF4 cleared more rapidly from the blood than anti-CD20 IgG, with early processing in the liver, spleen, and kidney. At 24 h, TF4 improved tumor uptake of (111)In-HSG-peptide 2.6-fold [13% versus 5% injected dose per gram (ID/g)] and enhanced tumor to blood ratios >45-fold (770 versus 17), compared with an anti-CD20 Fab x anti-HSG Fab chemical conjugate, and by 1.6-fold (9.0% versus 5.6% ID/g) and 1,600-fold (522 versus 0.32), respectively, compared with radiolabeled anti-CD20 IgG. A severe (>or=90%) and prolonged reduction of WBCs was observed at the maximum dose of (90)Y-anti-CD20 IgG, whereas pretargeting resulted in a <or=60% transient drop. TF4 pretargeting resulted in highly significant improvement in survival, curing 33% to 90% of the animals, even at relatively low doses, whereas most tumors progressed quickly without cures with (90)Y-anti-CD20 IgG. These results indicate an improved therapeutic index with pretargeted radioimmunotherapy (RAIT) using a DNL-constructed tri-Fab, bsMAb, compared with conventional therapy with directly radiolabeled antibody or with a chemically conjugated bsMAb. These encouraging results prompt testing these constructs for pretargeting RAIT in patients.
Project description:In preclinical models, anakinra, an IL-1 receptor antagonist (IL-1Ra), reduced immune effector cell-associated neurotoxicity syndrome (ICANS) without compromising anti-CD19 chimeric antigen receptor (CAR) T-cell efficacy. We initiated a phase 2 clinical trial of anakinra in patients with relapsed/refractory large B-cell lymphoma and mantle cell lymphoma treated with commercial anti-CD19 CAR T-cell therapy. Here we report a non-prespecified interim analysis reporting the final results from cohort 1 in which patients received subcutaneous anakinra from day 2 until at least day 10 post-CAR T-cell infusion. The primary endpoint was the rate of severe (grade ≥3) ICANS. Key secondary endpoints included the rates of all-grade cytokine release syndrome (CRS) and ICANS and overall disease response. Among 31 treated patients, 74% received axicabtagene ciloleucel, 13% received brexucabtagene ciloleucel and 4% received tisagenlecleucel. All-grade ICANS occurred in 19%, and severe ICANS occurred in 9.7% of patients. There were no grade 4 or 5 ICANS events. All-grade CRS occurred in 74%, and severe CRS occurred in 6.4% of patients. The overall disease response rate was 77% with 65% complete response rate. These initial results show that prophylactic anakinra resulted in a low incidence of ICANS in patients with lymphoma receiving anti-CD19 CAR T-cell therapy and support further study of anakinra in immune-related neurotoxicity syndromes.
Project description:BackgroundClinical success with chimeric antigen receptor (CAR)- based immunotherapy for leukemia has been accompanied by the associated finding that antigen-escape variants of the disease are responsible for relapse. To target hematologic malignancies with a chimeric antigen receptor (CAR) that targets two antigens with a single vector, and thus potentially lessen the chance of leukemic escape mutations, a tandem-CAR approach was investigated.MethodsAntigen binding domains from the FMC63 (anti-CD19) and Leu16 (anti-CD20) antibodies were linked in differing configurations to transmembrane and T cell signaling domains to create tandem-CARs. Expression on the surface of primary human T cells was induced by transduction with a single lentiviral vector (LV) encoding the tandem-CAR. Tandem-CARs were compared to single antigen targeting CARs in vitro and in vivo, and to an admixture of transduced cells expressing each CAR in vivo in immunodeficient (NSG) disease-bearing mice.ResultsTandem constructs efficient killed the Raji leukemia cell line both in vitro and in vivo. Tandem CARs generated less cytokine than the CD20 CAR, but similar to CD19 CARs, on their own. In co-culture experiments at low effector to target ratios with both single- and tandem- CAR-T cells, a rapid down-modulation of full-length CD19 expression was seen on leukemia targets. There also was a partial down-modulation of CD22, and to a lesser degree, of CD20. Our data also highlight the extreme sensitivity of the NALM-6 cell line to general lymphocyte-mediated cytotoxicity. While single and tandem constructs were effective in vivo in a standard setting, in a high-disease burden setting, the tandem CAR proved both effective and less toxic than an admixture of transduced T cell populations expressing single CARs.ConclusionTandem CARs are equally effective in standard disease models to single antigen specificity CARs, and may be both more effective and less toxic in a higher disease burden setting. This may be due to optimized cell killing with more moderate cytokine production. The rapid co-modulation of CD19, CD20, and CD22 may account for the ability to rapidly evolve escape mutants by selecting for leukemic clones that not require these target antigens for continued expansion.
Project description:Non-Hodgkin lymphoma (NHL) is a common malignancy in the hematologic system, and traditional therapy has limited efficacy for people with recurrent/refractory NHL (R/R NHL), especially for patients with diffuse large B cell lymphoma (DLBCL). Chimeric antigen receptor (CAR) T-cell therapy is a novel and effective immunotherapy strategy for R/R hematopoietic malignancies, but relapses can occur due to the loss of CAR-T cells in vivo or the loss of antigen. One strategy to avoid antigen loss after CAR-T cell therapy is to target one more antigen simultaneously. Tandem CAR targeting CD19 and CD22 has demonstrated the reliability of tandem CAR-T cell therapy for R/R B-ALL. This study explores the therapeutic potential of tandem CD19/20 CAR-T in the treatment of R/R B cell NHL. The efficacy and safety of autologous CD19/20 CAR-T cells in eleven R/R B cell NHL adult patients were evaluated in an open-label, single-arm trial. Most patients achieved complete response, exhibiting the efficacy and safety of tandem CD19/20 CAR-T cells. The TCR repertoire diversity of CAR-T cells decreased after infusion. The expanded TCR clones in vivo were mainly derived from TCR clones that had increased expression of genes associated with immune-related signaling pathways from the infusion product (IP). The kinetics of CAR-T cells in vivo were linked to an increase in the expression of genes related to immune response and cytolysis/cytotoxicity.