Chimeric Antigen Receptor-modified T Research Articles

A Phase 1 Study with Point-of-Care Manufacturing of Dual Targeted, Tandem Anti-CD19, Anti-CD20 Chimeric Antigen Receptor Modified T (CAR-T) Cells for Relapsed, Refractory, Non-Hodgkin Lymphoma

A Phase 1 Study with Point-of-Care Manufacturing of Dual Targeted, Tandem Anti-CD19, Anti-CD20 Chimeric Antigen Receptor Modified T (CAR-T) Cells for Relapsed, Refractory, Non-Hodgkin Lymphoma

Effective Chimeric Antigen Receptor T Cell Therapy for Relapsed and Refractory Acute Lymphoblastic Leukemia in Children Can be Administered Safely Under the Real-Time Monitoring of Th1/Th2 Cytokine Patterns Measured By the Cytometric Bead Array Technology

Background and Objectives: Chimeric antigen receptor modified T (CAR-T) cell therapy has emerged as a promising strategy for the treatment of relapsed and refractory hematological malignancies recently. CD19 chimeric antigen receptor T (CD19CAR-T) cell therapy is a representative case showing promising results in treating relapsed and refractory B-lineage acute lymphoblastic leukemia (r/r B-ALL). However, challenges remain due to the concurrent severe side-effects such as cytokine release syndrome (CRS) or neurological toxicities which may cause death if they are not properly managed. So, how to safely use the CAR-T cell therapy in patients has drawn a lot of concern and attention worldwide. The objective of this study was to investigate the cytokine patterns to early identify and monitor the severe side-effects of cytokine release syndrome (CRS) and neurotoxicity caused by the therapy so that the therapy can be safely administered. Patients and Method: From December 2015 to March 2017, five patients with r/r B-ALL treated with CD19CAR-T cells were enrolled in this study. The Th1/Th2 cytokines including Interleukin (IL)-2, IL-4, IL6, IL-10, Tumor necrosis factor (TNF) and Interferon-gamma (IFN-γ ) in the serum and cerebral spinal fluid (CSF) were quickly measured by cytometric bead array (CBA) technology which allowed the result being available within 5 hours after the samples taken. The test were repeated more than once a day during the therapy. Results: 5 pediatric patients (2 boys and 3 girls) with r/r B-ALL aged 4 months -12 years old were treated by CD19CAR-T cell therapy. Four patients achieved complete remission (80% of CR rate) with minimal residual diseases (MRD) negative detected by flow cytometry within 2 weeks. One patient did not respond to the therapy due to the poor quality of his T cells. Five to 10 times of cytokine measurements were carried out for the five patients. Two types of cytokine patterns were identified: (1) very high levels of IL-6, IFN-γ with moderately elevated IL-10 indicated the CAR-T therapy effective pattern; (2) IL-6 slightly - severely elevated IL-6 level without concurrent elevation of IFN-γ represented a CAR-T cell therapy ineffective pattern but rather indicating a current infection. All the four responding patients presented the CAR-T therapy effective cytokine pattern, while the non-responding patient presented the CAR-T therapy ineffective cytokine pattern. We also analyzed the relationship between the cytokine levels and the severity of the side-effects and found that they were highly correlated. The cytokine levels in the CSF of two patients with seizure were also measured and we found that the elevation of the cytokine pattern in the CSF was paralleled to those in their serum but CNS-leukemia and CAR-T cells in their CSFs were not detected, indicating that the neurotoxicity concurrently presented in these two patients might be caused by the cytokines in the serum leaked into the CSF through the blood brain barrier. Extremely high level of cytokines occurred at 12 hours after CAR-T cell infusion in a patient was identified immediately and treated timely in onn-ICU setting to avoid the fatal consequence. Acute toxicities including fever, hypotension and other neurological toxicities occurred in responding patients within 2 weeks post infusion and managed properly with tocilizumab and/or steroids according to the “real-time” monitoring of this simple 6-Th1/Th2 cytokine patterns at the non-ICU setting. In conclusion, our study demonstrates that CD19CAR-T cell therapy can be administered safely for patients with relapsed and refractory leukemia under the “real-time” monitoring of a simple 6-cytokine pattern. DisclosuresNo relevant conflicts of interest to declare.

Progress of chimeric antigen receptor modified natural killer cells immunotherapy in hematological neoplasms

Chimeric antigen receptor modified T (CAR-T) cells have been a kind of promising immunotherapeutic strategy for the treatment of malignances, which could target the specific antigen and exert a specific cytotoxic effect by gene modification of T cells. There has been a great stride in B lymphocytic leukemia along with CAR-T therapy. As the essential effector cells of the innate immune system, natural killer (NK) cells play a critical role in host immunity against cancer and have a wide application prospect in the tumor immunotherapy. The potential of CAR modification in NK cells has also attracted much attention. A lot of remarkable results have been obtained in vitro experiments and animal model of CAR-NK targeting hematologic neoplasms. This paper reviews the progress of CAR-NK immunotherapy in hematological malignancies. Key words: Hematologic neoplasms; Chimeric antigen receptor; Killer cells, natural

Increased antitumor activities of glypican-3-specific chimeric antigen receptor-modified T cells by coexpression of a soluble PD1-CH3 fusion protein.

Our recent clinical study demonstrated that glypican-3 (GPC3)-specific chimeric antigen receptor-modified T (CAR-T) cells are a promising treatment for hepatocellular carcinoma (HCC). However, the interaction of programmed cell death 1 (PD-1) and PD-L1-mediated T-cell inhibition is involved in immune evasion in a wide range of solid tumors, including HCC. To overcome this problem, we introduced a fusion protein composed of a PD-1 extracellular domain and CH3 from IgG4 into GPC3-specific CAR-T cells (GPC3-28Z) to block the PD-1/PD-L1 pathway. GPC3-specific CAR-T cells carrying the PD-1-CH3 fusion protein (sPD1) specifically recognized and lysed GPC3-positive HCC cells. The proliferation capacity of GPC3-28Z-sPD1 T cells after weekly stimulation with target cells was much higher than that of control GPC3-28Z T cells. Additionally, the coexpression of sPD1 could protect CAR-T cells from exhaustion when incubated with target cells, as phosphorylated AKT and Bcl-xL expression levels were higher in GPC3-28Z-sPD1 T cells than in GPC3-28Z cells. Importantly, in two HCC tumor xenograft models, GPC3-28Z-sPD1 T cells displayed a significantly higher tumor suppression capacity than GPC3-28Z T cells. In addition, an increased number of CD3+ T cells in the circulation and tumors and increased granzyme B levels and decreased Ki67 expression levels in the tumors were observed in the mice treated with GPC3-28Z-sPD1 T cells. Together, these data indicated that GPC3-specific CAR-T cells carrying sPD1 show promise as a treatment for patients with HCC.

Abstract 4046: The different immune evasion mechanisms in human prostate cancer

Abstract Cancer development is associated with a number of genetic and epigenetic alternations. Normally, these alterations are detected by the immune system in a process called immune surveillance, where cancer cell killing is mediated by cytotoxic T lymphocytes (CTL) and natural killer cells (NK cells). Yet, tumor progression and development indicate that cancer cells have acquired mechanisms to avoid immune destruction. Various immune evasion mechanisms have been reported before such as impaired antigen presentation and activation of CTL and NK cells, immunosuppression, and induction of tolerance. Although current treatment methods are shifting towards more targeted strategies in prostate cancer, such as immunotherapy, a better understanding of the cancer-immune interactions and immune evasion mechanisms is yet to be established. More immunotherapies are being developed and approved by the FDA for treating cancer. In prostate cancer, Sipuleucel-T, an autologous cellular immunotherapy, was approved by FDA for the treatment of asymptomatic or minimally symptomatic metastatic castrate resistant (hormone refractory) prostate cancer. Intensive investigation on other immunotherapies is ongoing in prostate cancer. These include blockade of negative checkpoint regulators (PD-1, CTLA4) and Ig superfamily member V-domain Ig-containing suppressor of T-cell activation (VISTA), chimeric antigen receptor-modified T (CAR-T) cells against prostate lineage-unique proteins (PLUPs), and monoclonal antibodies targeting immunoinhibitory molecules. However, the optimal choice of treatment for a prostate cancer patient needs to target their specific mechanisms of immune evasion, which are poorly studied. In this study, we will use The Cancer Genome Atlas RNA-seq data to check for immune evasion gene expression in prostate cancer patients to identify at the different mechanisms by which cancer avoids immune destruction. We will use a sequential biclustering algorithm developed by our group, to group prostate cancer patients based on their similarities in immune evasion gene expression. A similar unpublished work was done by our group on breast cancer where we identified 7 different groups of patients, each with different mechanisms or combination of evasion mechanism. We also showed that triple negative breast cancer can be immunogenic and non-immunogenic. This group-based identification of evasion mechanisms will not only provide a better understanding of the different immune evasion mechanisms in prostate cancer, but will also shed light on potential combinations of mechanism. This in turn, will help guide the choice of single and combined immunotherapeutic approches. Citation Format: Mayassa J. Bou-Dargham, Yuhang Liu, Qing-Xiang Amy Sang, Jinfeng Zhang. The different immune evasion mechanisms in human prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4046.

CART Targeting of Solid Tumors: More Pieces to the Puzzle.

Chimeric antigen receptor-modified T (CART)-cell-based targeting of solid tumors remains a considerable and worthwhile challenge in the field of immunotherapy. The role of chemotherapy to target stroma and enhance chimeric antigen receptor (CAR) cell antitumor function, expansion, and persistence is still unresolved. Clin Cancer Res; 24(6); 1246-7. ©2018 AACRSee related article by Guo et al., p. 1277.

An experimental study of CD4 targeted chimeric antigen receptor modified T cell with anti-lymphoma activity

目的探讨针对CD4膜蛋白的CAR-T细胞对CD4+T细胞淋巴瘤细胞的靶向特异性杀伤作用。方法采用重组DNA技术构建含4-1BB共刺激分子的第二代针对CD4的CAR慢病毒载体，应用293T细胞包装慢病毒，采用流式细胞术检测T细胞的转染效率及T细胞亚群动态变化，采用流式细胞术微球法检测培养上清中IFN-γ浓度。结果①构建的慢病毒载体转染激活的T细胞后CAR膜蛋白阳性率达到50.0%~70.0%。T细胞激活后部分CD8+T细胞弱表达（dim）CD4膜蛋白。T细胞转染针对CD4的CAR慢病毒后CD4+ T细胞、CD8+ CD4dim T细胞逐渐被清除。②CAR-T细胞、对照组T细胞（空载体转染的T细胞）以8∶1效靶比分别与CD4+人T细胞淋巴瘤细胞株KARPAS 299细胞共培养24 h，杀伤效率分别为（96.9±2.1）%和（11.2±3.1）%，前者明显高于后者（t=7.137，P=0.028）。③CAR-T细胞单独培养，与转染慢病毒载体表达人CD4的K562细胞（K562-CD4细胞）、K562细胞共培养后上清中IFN-γ浓度分别为（1 785±268）、（15 648±2 168）、（1 978±354）pg/ml，CAR-T细胞与K562-CD4细胞共培养上清IFN-γ浓度明显高于其他两组，差异有统计学意义（P<0.01）。结论CD4特异性CAR-T细胞效应细胞免疫表型为CD8+ CD4+ T细胞，在体外具有杀伤正常CD4+ T细胞和CD4+ T细胞淋巴瘤细胞的活性，对于CD4dim T细胞也有较好的清除活性。

CAR-T cell therapy in ovarian cancer: from the bench to the bedside.

Ovarian cancer (OC) is the most lethal gynecological malignancy and is responsible for most gynecological cancer deaths. Apart from conventional surgery, chemotherapy, and radiotherapy, chimeric antigen receptor-modified T (CAR-T) cells as a representative of adoptive cellular immunotherapy have received considerable attention in the research field of cancer treatment. CARs combine antigen specificity and T-cell-activating properties in a single fusion molecule. Several preclinical experiments and clinical trials have confirmed that adoptive cell immunotherapy using typical CAR-engineered T cells for OC is a promising treatment approach with striking clinical efficacy; moreover, the emerging CAR-Ts targeting various antigens also exert great potential. However, such therapies have side effects and toxicities, such as cytokine-associated and “on-target, off-tumor” toxicities. In this review, we systematically detail and highlight the present knowledge of CAR-Ts including the constructions, vectors, clinical applications, development challenges, and solutions of CAR-T-cell therapy for OC. We hope to provide new insight into OC treatment for the future.

Abstract CT041: The clinical study on CD19-directed chimeric antigen receptor-modified T cells in patient with Richter Syndrome

Abstract Richter syndrome (RS) indicates the transformation of chronic lymphocytic leukemia (CLL) into an aggressive lymphoma (mostly DLBCL). RS is a rare complication with unfavorable clinical outcome. There is no effective treatment for it currently. As a new type of cell-based immune therapy, chimeric antigen receptor modified T (CAR-T) cell treatment is now widely used in treating hematological malignancies, especially in CD19+ B cell malignancy. Therefore, CD19-directed chimeric antigen receptor modified T cells (CART-19) treatment is worthwhile to be developed as a new method for Richter Syndrome’s patients. In this study, the patient with Richter Syndrome expressing high level of CD19 was enrolled in a clinical trial. The patient had received a series of standard treatments with no therapeutic effect before 4.55 x 108 autologous CART-19 cells were infused, of which approximately 50% were transduced with the CAR. After CART-19 infusion, the main side effects were repeated fever, pancytopenia and significant rises of serum cytokines, including IFN-γ, IL-6 and IL-10. However, before discharge, the level of cytokines reduced to normal level. In addition, we detected K+, Ca2+, creatinine and glutamic-pyruvic transaminase, and found all of these were normal, which suggested that there was no significant tumor necrosis after treatment. The treatment included two courses. During the first course, the patient was infused with 4 x 107 CART-19 cells twice, followed by 1 x 108 cells in the 3rd infusion and then 1x106 cells in the 4th infusion. After these infusions, the proportion of B cells in the patient’s peripheral blood decreased from 72% to 40%, accompanied by reduced size of cervical, mediastinal and axillary lymph nodes. Eighteen days later, the patient was infused in the second course with 3.7x107 CART-19 cells twice, followed by 1x108 cells twice. After the second course, the proportion of B cells maintained at approximate 85%, and the lymph nodes enlargement was observed as disease progression. Based on the recent therapeutic landscape for hematological malignancies including B cell lymphomas, CD19-CAR T cell therapy may offer a new therapeutic option for RS, which aims to reduce the patients’ tumor burden, prolong their survival time, and provide opportunities for combined therapy with chemotherapy and bone marrow transplantation. Note: This abstract was not presented at the meeting. Citation Format: Leiming Xia, Qian Chen, Qiao Li, Tan Li, Yi Wang, Yangyi Bao. The clinical study on CD19-directed chimeric antigen receptor-modified T cells in patient with Richter Syndrome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT041. doi:10.1158/1538-7445.AM2017-CT041

Abstract 2438: Analysis of IL-13 signaling through IL-13Rα2 in human brain tumor specimens in situ

Abstract Previously, we have demonstrated that IL-13 receptor alpha2 (IL-13Rα2), a high affinity receptor for Th2 cytokine IL-13, is overexpressed in most glioblastoma multiforme (GBM) cell lines and approximately 78% of the patient-derived samples. We have also demonstrated that IL-13Rα2 can be targeted by a number of immunotherapeutic agents including chimeric antigen receptor modified T (CAR-T) cells, targeted lentivirus and adenovirus vectors, and a chimeric fusion immunotoxin consisting of IL-13 and truncated Pseudomonas exotoxin (IL-13-PE). However, the signal transduction initiated by IL-13 in GBM tumor is not known to occur through the IL13Rα2, which has a high affinity for IL-13. We have recently observed that IL-13 can signal through IL-13Rα2 by activating AP-1 transcription factors in human brain tumor cell lines. In this study, we have examined IL-13Rα2 expression in human brain tumor and normal brain specimens, and the subsequent signaling through the AP-1 pathway in situ. Using six human glioblastoma and three astrocytoma specimens, we evaluated the expression of AP-1 transcription factors by immunohistochemistry (IHC) and compared the extent of immunostaining and percent positive fields with three normal brain specimens. Six GBM specimens examined showed high degree of immunostaining for c-Fos, c-Jun, Jun D and Fra-1 (AP-1 family of transcription factors) and a high percentage of positive fields. These specimens also showed strong immunostaining for IL-13Rα2 (4+) in &amp;gt;70% fields (P&amp;lt;0.001 compared to normal brain). Three astrocytoma specimens showed staining for IL-13Rα2 (&amp;gt;2+ and 32% fields, P&amp;lt;0.01 compared to normal brain), but the extent of staining was lower compared to GBM. Similar to IL-13Rα2 expression, the extent of staining and percentage of positive fields for AP-1 transcription factors were highly statistically significant between tumors and normal brain (P&amp;lt;0.001 for GBM compared to normal brain and P&amp;lt;0.01 for astrocytoma compared to normal brain). The extent of immunostaining in GBM was highest for c-Fos (4+, 78% fields) followed by c-Jun (3+, 57% fields), Fra-1 (2+, 70% fields) and Jun-D (2+, 28% fields). Jun-B expression was the lowest among the AP-1 transcription factors (&amp;lt;1+, 7% fields) in GBM specimens. Astrocytoma specimens showed lesser extent of immunostaining for AP-1 members compared to GBM; c-Fos showed 2+ staining and 42% positive fields followed by c-Jun (2+, 12% fields), Fra-1 (2+, 48% fields) and Jun-D (&amp;lt;1+, 18% fields). Jun-B staining intensity was &amp;lt;1+ in only 6% fields. Normal brain specimens showed no immunostaining for AP-1 family members. Our results generally corroborate with data obtained from GBM cell lines and confirm that IL-13 can signal in IL-13Rα2 positive GBM tumors in-situ through the AP-1 pathway, thus indicating that this pathway may be an important target for therapeutic intervention of GBM in addition to targeting IL-13Rα2. Citation Format: Rukmini Bhardwaj, Akiko Suzuki, Pamela Leland, Bharat H. Joshi, Raj K. Puri. Analysis of IL-13 signaling through IL-13Rα2 in human brain tumor specimens in situ [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2438. doi:10.1158/1538-7445.AM2017-2438

Efficacy of anti-CD19 chimeric antigen receptor modified T(CAR-T) cell therapy in Chinese patients with relapsed/refractory acute lymphocytic leukemia in a multicenter trial.

7028 Background: r/r B-ALL was reported as the most-threatening disease because of the low disease free survival even treatment with allogeneic hematopoietic stem cell transplantation. For overcoming conventional therapies limitation, autologous CD19CAR-T was performed in our clinical trials to induce remission in patients with r/r disease. 30 patients (from 7 clinical centers, in China) as volunteers with r/r B-ALL were treated by autologous CD19 CAR-T. Methods: 5 juveniles and 25 adults with r/r ALL received autologous CD19 targeted CAR-T, the doses between 1.03 × 106 CAR-T cells/kg and 10.09 × 106CAR-T cells/kg. These 30 cases(from 7 clinical centers, in China) were treated with CAR-T cells from May. 8 2015 to January. 4 2017 (Table1). Patients were monitored for a response. Highly standardized CAR T cell preparation protocol and manageable CRS in most were kept for no significant difference in 7 clinical centers. Results: After treated with CAR-T, a total of 30 cases (5 juveniles and 25 adults coming from 7 clinical centers, in China) with r/r B-ALL were all detected the CAR-T cells proliferated in the blood and bone marrow. The results showed that complete remission (CR) is 26/30(86.67% ) between day7-14 after CD19 CART cell infusion, and 25/30(83.33%) cases arrived at MRD negative. There is about 1/3 of the total cases receiving a repeat infusions following initial ones since these patients have no safety concerns. Additionaly, the severe Cytokine release syndrome (CRS) was 8/30(26.67%) of cases and 24/30(80%) of cases was seen CRS. The anti-IL6R agent tocilizumab and Methylprednisolone were effective confrontation Severe CRS. Conclusions: This is the first multicentre report to our knowledge of successful treatment of r/r ALL with anti-CD19 CAR T cells in China. Even r/r B-ALL with high-burden leukemia patients also was effective and associated with a high remission rate after infused autologous CD19 CAR-T).(NCT 02813837).

Effect of chimeric antigen receptor-modified T (CAR-T) cells on responses in children with non-CNS extramedullary relapse of CD19+ acute lymphoblastic leukemia (ALL).

10507 Background: Anti-CD19 CAR-T cell therapies have shown high efficacy in inducing durable marrow responses in patients with relapsed/refractory CD19+ ALL. We now report on outcome of 10 patients with extramedullary (EM) involvement of ALL treated with CAR-T, including 5 patients who had EM disease at time of infusion. Methods: We identified patients treated on pediatric phase 1/2a trials of murine (CTL019) or humanized (CTL119) anti-CD19 CAR-T cells for isolated EM or BM/EM relapse of ALL. EM relapse was defined as involvement of non-CNS site by imaging +/- pathology within 12 months (mos) of infusion. Post infusion, patients had diagnostic imaging done at 1, 3, 6, 9, and 12 mos. Results: Among 97 patients receiving CAR-T, ten (CTL019, n=6; CTL119, n=4) were identified who had EM involvement on average 2.3 mos (range 0-9 mos) prior to infusion; including 5/10 at time of infusion. Sites of EM relapses included testes, sinus, parotid, bone, uterus, kidney and skin, and 5 patients had multiple sites of EM involvement. Patients ranged from 2-4 relapses of their ALL pre-CAR-T. Two had isolated EM relapse (sites were parotid and multifocal bony lesions in one; testis and sinus in second). All 10 patients had undergone hematopoietic stem cell transplantation prior to EM relapse, 2 had received radiation directed to the EM site prior to CAR-T. Five patients evaluated by serial imaging had objective responses: 2 had resolution of EM disease by day 28; 2 had resolution by 3 mos; 1 had continued decrease in size of uterine mass at 3 and 6 mos and underwent hysterectomy at 8 mos with no evidence of disease on pathology. In the 4 patients with prior history of skin or testicular involvement, there was no evidence by exam at day 28. One patient had progressive EM disease within 2 weeks of CAR-T cell infusion and died at 6 weeks. Three relapsed with CD19+ disease [1 skin/medullary- died at 38 mos post CAR-T; 2 medullary (1 died at 17 mos, 1 alive at 28 mos)]. The remaining 6 are alive and well at median follow-up of 10 mos (range 3-16 mos) without recurrence of disease. Conclusions: Single agent CAR-T immunotherapy can induce potent and durable responses in patients with EM relapse of their ALL. Clinical trial information: NCT01626495, NCT02374333.

Development of T cells carrying two complementary chimeric antigen receptors against glypican-3 and asialoglycoprotein receptor 1 for the treatment of hepatocellular carcinoma.

Adoptive immunotherapy leveraging chimeric antigen receptor-modified T (CAR-T) cells holds great promise for the treatment of cancer. However, tumor-associated antigens often have low expression levels in normal tissues, which can cause on-target, off-tumor toxicity. Recently, we reported that GPC3-targeted CAR-T cells could eradicate hepatocellular carcinoma (HCC) xenografts in mice. However, it remains unknown whether on-target, off-tumor toxicity can occur. Therefore, we proposed that dual-targeted CAR-T cells co-expressing glypican-3 (GPC3) and asialoglycoprotein receptor 1 (ASGR1) (a liver tissue-specific protein)-targeted CARs featuring CD3ζ and 28BB (containing both CD28 and 4-1BB signaling domains), respectively, may have reduced on-target, off-tumor toxicity. Our results demonstrated that dual-targeted CAR-T cells caused no cytotoxicity to ASGR1+GPC3- tumor cells, but they exhibited a similar cytotoxicity against GPC3+ASGR1- and GPC3+ASGR1+ HCC cells in vitro. We found that dual-targeted CAR-T cells showed significantly higher cytokine secretion, proliferation and antiapoptosis ability against tumor cells bearing both antigens than single-targeted CAR-T cells in vitro. Furthermore, the dual-targeted CAR-T cells displayed potent growth suppression activity on GPC3+ASGR1+ HCC tumor xenografts, while no obvious growth suppression was seen with single or double antigen-negative tumor xenografts. Additionally, the dual-targeted T cells exerted superior anticancer activity and persistence against single-targeted T cells in two GPC3+ASGR1+ HCC xenograft models. Together, T cells carrying two complementary CARs against GPC3 and ASGR1 may reduce the risk of on-target, off-tumor toxicity while maintaining relatively potent antitumor activities on GPC3+ASGR1+ HCC.

Chimeric antigen receptor-modified T cells for the immunotherapy of patients with EGFR-expressing advanced relapsed/refractory non-small cell lung cancer.

The successes achieved by chimeric antigen receptor-modified T (CAR-T) cells in hematological malignancies raised the possibility of their use in non-small lung cancer (NSCLC). In this phase I clinical study (NCT01869166), patients with epidermal growth factor receptor (EGFR)-positive (>50% expression), relapsed/refractory NSCLC received escalating doses of EGFR-targeted CAR-T cell infusions. The EGFR-targeted CAR-T cells were generated from peripheral blood after a 10 to 13-day in vitro expansion. Serum cytokines in peripheral blood and copy numbers of CAR-EGFR transgene in peripheral blood and in tissue biopsy were monitored periodically. Clinical responses were evaluated with RECIST1.1 and immune- related response criteria, and adverse events were graded with CTCAE 4.0. The EGFR-targeted CAR-T cell infusions were well-tolerated without severe toxicity. Of 11 evaluable patients, two patients obtained partial response and five had stable disease for two to eight months. The median dose of transfused CAR(+) T cells was 0.97×10(7) cells kg(-1) (interquartile range (IQR), 0.45 to 1.09×10(7) cells kg(-1)). Pathological eradication of EGFR positive tumor cells after EGFR-targeted CAR-T cell treatment can be observed in tumor biopsies, along with the CAR-EGFR gene detected in tumor-infiltrating T cells in all four biopsied patients. The EGFR-targeted CAR-T cell therapy is safe and feasible for EGFR-positive advanced relapsed/refractory NSCLC.

Tolerance and efficacy of autologous or donor-derived T cells expressing CD19 chimeric antigen receptors in adult B-ALL with extramedullary leukemia

The engineering of T lymphocytes to express chimeric antigen receptors (CARs) aims to establish T cell-mediated tumor immunity rapidly. In this study, we conducted a pilot clinical trial of autologous or donor- derived T cells genetically modified to express a CAR targeting the B-cell antigen CD19 harboring 4-1BB and the CD3ζ moiety. All enrolled patients had relapsed or chemotherapy-refractory B-cell lineage acute lymphocytic leukemia (B-ALL). Of the nine patients, six had definite extramedullary involvement, and the rate of overall survival at 18 weeks was 56%. One of the two patients who received conditioning chemotherapy achieved a three-month durable complete response with partial regression of extramedullary lesions. Four of seven patients who did not receive conditioning chemotherapy achieved dramatic regression or a mixed response in the haematopoietic system and extramedullary tissues for two to nine months. Grade 2–3 graft-versus-host disease (GVHD) was observed in two patients who received substantial donor-derived anti-CD19 CART (chimeric antigen receptor-modified T) cells 3–4 weeks after cell infusions. These results show for the first time that donor-derived anti-CD19 CART cells can cause GVHD and regression of extramedullary B-ALL. This study is registered at www.clinicaltrials.gov as NCT01864889.