scholarly journals In vivo generation of human CD 19‐ CAR T cells results in B‐cell depletion and signs of cytokine release syndrome

2018 ◽  
Vol 10 (11) ◽  
Author(s):  
Anett Pfeiffer ◽  
Frederic B Thalheimer ◽  
Sylvia Hartmann ◽  
Annika M Frank ◽  
Ruben R Bender ◽  
...  
2019 ◽  
Vol 11 (482) ◽  
pp. eaav1648 ◽  
Author(s):  
Rita Kansal ◽  
Noah Richardson ◽  
Indira Neeli ◽  
Saleem Khawaja ◽  
Damian Chamberlain ◽  
...  

The failure of anti-CD20 antibody (Rituximab) as therapy for lupus may be attributed to the transient and incomplete B cell depletion achieved in clinical trials. Here, using an alternative approach, we report that complete and sustained CD19+ B cell depletion is a highly effective therapy in lupus models. CD8+ T cells expressing CD19-targeted chimeric antigen receptors (CARs) persistently depleted CD19+ B cells, eliminated autoantibody production, reversed disease manifestations in target organs, and extended life spans well beyond normal in the (NZB × NZW) F1 and MRLfas/fas mouse models of lupus. CAR T cells were active for 1 year in vivo and were enriched in the CD44+CD62L+ T cell subset. Adoptively transferred splenic T cells from CAR T cell–treated mice depleted CD19+ B cells and reduced disease in naive autoimmune mice, indicating that disease control was cell-mediated. Sustained B cell depletion with CD19-targeted CAR T cell immunotherapy is a stable and effective strategy to treat murine lupus, and its effectiveness should be explored in clinical trials for lupus.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2769-2769
Author(s):  
Justine Cunningham ◽  
Sundeep Chandra ◽  
Akinola Emmanuel ◽  
Allyse Mazzarelli ◽  
Carmela Passaro ◽  
...  

Abstract Introduction: Ex vivo manufactured chimeric antigen receptor (CAR) T cell therapies are highly effective for treating B cell malignancies. However, the complexity, cost and time required to manufacture CAR T cells limits access. To overcome conventional ex vivo CAR T limitations, a novel gene therapy platform has been developed that can deliver CAR transgenes directly to T cells through systemic administration of a fusosome, an engineered, target-directed novel paramyxovirus-based integrating vector that binds specific cell surface receptors for gene delivery through membrane fusion. Here, we demonstrate that systemic administration of a CD8a-targeted, integrating vector envelope (i.e., fusogen) encoding an anti-CD20 CAR into Southern pig-tail macaques (M. nemestrina), which is a species permissive to the integrating vector-mediated transduction, results in T cell transduction and B cell depletion with no treatment-related toxicities. Methods: CD8a-specific single chain variable fragments (scFvs) were generated and measured for target specificity versus non-CD8-expressing cells in vitro. Cross-reactivity of the CD8a-specific fusogen for human and nemestrina T cells was confirmed in vitro. Targeted fusogens were then used to pseudotype integrating vector expressing an anti-CD20 CAR containing the 4-1BB and CD3zeta signaling domains (CD8a-anti-CD20CAR). Transduction and B cell killing was confirmed on human and nemestrina PBMCs. To evaluate in vivo activity, normal, healthy nemestrina macaques were treated with a single dose of CD8a-targeted anti-CD20 CAR fusosome (n=6) or saline (n=2) via intravenous infusion at 10mL/kg/hr for 1-hour and evaluated for up to 52 days for evidence of adverse effects, B cell depletion, CAR-mediated cytokine production, CAR T cell persistence and vector biodistribution using ddPCR and anti-CD20CAR transgene by RT-ddPCR to detect transgene levels. Histopathology of several organs and immunohistochemistry for CD3 and CD20 on lymph nodes, spleen, and bone marrow were performed at termination (days 35 and 52). Tolerability of the treatment was assessed by body weight, body temperature, neurological exams, serum chemistry panel, and complete blood counts pre-dose and post-dose up to 52 days. Results: The CD8a-targeted fusogen demonstrated CD8a-specificity versus human CD8 negative cell lines, and cross-reactivity and transduction efficiency in nemestrina PBMCs in vitro. Compared to a control vector (GFP), anti-CD20CAR-modified T cells showed a dose-dependent depletion of B cells using in vitro assays. Following infusion of CD8a-anti-CD20CAR fusosomes into macaques, pharmacological activity in peripheral blood was detected by a reduction of B cells in 4 of 6 animals after 7 to 10 days. Two animals showed persistent B cell depletion until study termination, with two others showing a temporary response. The presence of vector copy could be detected in the peripheral blood of all treated animals between days 3 and 10, and in isolated spleen cells in 5 of 6 animals. All control animals (saline) were negative for vector. RT-ddPCR mRNA expression similarly revealed the presence of anti-CD20CAR transcripts in isolated spleen cells from treated animals; no expression was detected in tissues from control animals. Elevations in inflammatory cytokines could be detected in the serum of treated animals between days 3 and 14. Fusosome treatment was well-tolerated in all animals with no evidence of adverse effects. Moreover, T cell transduction and B cell depletion was not associated with cytokine-related toxicities, and blood chemistry and histopathology were within normal limits. Conclusion: These data obtained in an immunologically competent animal demonstrate the proof-of-concept that systemic administration of a CD8a-anti-CD20CAR fusosome can specifically transduce T cells in vivo without pre-conditioning or T cell activation, resulting in B cell depletion in the absence of vector- or CAR T-related toxicities. Therefore, fusosome technology represents a novel therapeutic opportunity to treat patients with B cell malignancies and potentially overcome some of the treatment barriers that exist with conventional CAR T therapies. Disclosures Cunningham: Sana Biotechnology: Current Employment. Chandra: Sana Biotechnology: Current Employment. Emmanuel: Sana Biotechnology: Current Employment. Mazzarelli: Sana Biotechnology: Current Employment. Passaro: Sana Biotechnology: Current Employment. Baldwin: Sana Biotechnology: Current Employment. Nguyen-McCarty: Sana Biotechnology: Current Employment. Rocca: Sana Biotechnology: Current Employment. Joyce: Sana Biotechnology: Current Employment. Kim: Sana Biotechnology: Current Employment. Vagin: Sana Biotechnology: Current Employment. Kaczmarek: Sana Biotechnology: Current Employment. Chavan: Sana Biotechnology: Current Employment. Jewell: Sana Biotechnology: Current Employment. Lipsitz: Sana Biotechnology: Current Employment. Shamashkin: Sana Biotechnology: Current Employment. Hlavaty: Sana Biotechnology: Current Employment. Rodriguez: Sana Biotechnology: Current Employment. Co: Sana Biotechnology: Current Employment. Cruite: Sana Biotechnology: Current Employment. Ennajdaoui: Sana Biotechnology: Current Employment. Duback: Sana Biotechnology: Current Employment. Elman: Sana Biotechnology: Current Employment. Amatya: Sana Biotechnology: Current Employment. Harding: Sana Biotechnology: Current Employment. Lyubinetsky: Sana Biotechnology: Current Employment. Patel: Sana Biotechnology: Current Employment. Pepper: Sana Biotechnology: Current Employment. Ruzo: Sana Biotechnology: Current Employment. Iovino: Sana Biotechnology: Current Employment. Varghese: Sana Biotechnology: Current Employment. Foster: Sana Biotechnology: Current Employment. Gorovits: Sana Biotechnology: Current Employment. Elpek: Sana Biotechnology: Current Employment. Laska: Sana Biotechnology: Current Employment. McGill: Sana Biotechnology: Current Employment. Shah: Sana Biotechnology: Current Employment. Fry: Sana Biotechnology: Current Employment, Current equity holder in publicly-traded company. Dambach: Sana Biotechnology: Current Employment.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. SCI-24-SCI-24
Author(s):  
Crystal L. Mackall

Unparalleled remission rates in patients with chemorefractory B-ALL treated with CD19-CAR T cells illustrate the potential for immunotherapy to eradicate chemoresistant cancer. CD19-CAR therapy is poised to fundamentally alter the clinical approach to relapsed B-ALL and ultimately may be incorporated into frontline therapy. Despite these successes, as clinical experience with this novel modality has increased, so has understanding of factors that limit success of CD19-CAR T cells for leukemia. These insights have implications for the future of cell based immunotherapy for leukemia and provide a glimpse of more global challenges likely to face the emerging field of cancer immunotherapy. Five challenges limiting the overall effectiveness of CD19-CAR therapy will be discussed: 1) T cell exhaustion is a differentiation pathway that occurs in T cells subjected to excessive T cell receptor signaling. A progressive functional decline occurs, manifest first by diminished proliferative potential and cytokine production, following by diminished cytolytic function and ultimately cell death. High leukemic burdens predispose CD19-CAR T cells to exhaustion as does the presence of a CD28 costimulatory signal, while a 4-1BB costimulatory signal diminishes the susceptibility to exhaustion. This biology is likely responsible for limited CD19-CAR persistence observed in clinical trials using a CD19-zeta-28 CAR compared to that observed using a CD19-zeta-BB CAR. 2) Leukemia resistance occurs in approximately 20% of patients treated with CD19-CAR and is associated with selection of B-ALL cells lacking CD19 targeted by the chimeric receptor. Emerging data demonstrates two distinct biologies associated with CD19-epitope loss. Isoform switch is characterized by an increase in CD19 isoforms specifically lacking exon 2, which binds the scFvs incorporated into CD19-CARs currently in clinical trials. Lineage switch is characterized by a global change in leukemia cell phenotype, and is associated with dedifferentiation toward a more stem-like, or myeloid leukemia in the setting of CD19-CAR for B-ALL. These insights raise the prospect that effectiveness of immunotherapy for leukemia may be significantly enhanced by targeting of more than one leukemia antigen. 3) CAR immunogenicity describes immune responses induced in the host that can lead to rejection of the CD19-CAR transduced T cells. Anti-CAR immune responses have been observed by several groups, and mapping is underway to identify the most immunogenic regions of the CAR, as a first step toward preventing this complication. 4) The most common toxicities associated with CD19-CAR therapy are cytokine release syndrome, neurotoxicity and B cell aplasia. Cytokine release syndrome is primarily observed in the setting of high disease burdens and efforts are underway to standardize grading and treatment algorithms to diminish morbidity. Increased information is needed to better understand the neurotoxicity observed in the context of this therapy. Although clinical data is limited, B cell aplasia appears to be adequately treated with IVIG replacement therapy. 5) Technical graft failure (e.g. inadequate expansion/transduction) is a challenge that has received limited attention, primarily since many trials have not reported the percentage of patients in whom adequate products could not be generated. We have observed that technical graft failure is often associated with a high frequency of contaminating myeloid populations in the lymphocyte product and selection approaches designed to eradicate myeloid populations have resulted in improved T cell expansion and transduction. These results suggest that optimization of lymphocyte selection may diminish the incidence of technical graft failure. Disclosures Mackall: Juno: Patents & Royalties: CD22-CAR. Off Label Use: cyclophosphamide.


Author(s):  
Jeremy S. Abramson ◽  
Matthew Lunning ◽  
M. Lia Palomba

Aggressive B-cell lymphomas that are primary refractory to, or relapse after, frontline chemoimmunotherapy have a low cure rate with conventional therapies. Although high-dose chemotherapy remains the standard of care at first relapse for sufficiently young and fit patients, fewer than one-quarter of patients with relapsed/refractory disease are cured with this approach. Anti-CD19 chimeric antigen receptor (CAR) T cells have emerged as an effective therapy in patients with multiple relapsed/refractory disease, capable of inducing durable remissions in patients with chemotherapy-refractory disease. Three anti-CD19 CAR T cells for aggressive B-cell lymphoma (axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene ciloleucel) are either U.S. Food and Drug Administration approved or in late-stage development. All three CAR T cells produce durable remissions in 33%–40% of treated patients. Differences among these products include the specific CAR constructs, costimulatory domains, manufacturing process, dose, and eligibility criteria for their pivotal trials. Notable toxicities include cytokine release syndrome and neurologic toxicities, which are usually treatable and reversible, as well as cytopenias and hypogammaglobulinemia. Incidences of cytokine release syndrome and neurotoxicity differ across CAR T-cell products, related in part to the type of costimulatory domain. Potential mechanisms of resistance include CAR T-cell exhaustion and immune evasion, CD19 antigen loss, and a lack of persistence. Rational combination strategies with CAR T cells are under evaluation, including immune checkpoint inhibitors, immunomodulators, and tyrosine kinase inhibitors. Novel cell products are also being developed and include CAR T cells that target multiple tumor antigens, cytokine-secreting CAR T cells, and gene-edited CAR T cells, among others.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 168-168 ◽  
Author(s):  
James N. Kochenderfer ◽  
Mark E. Dudley ◽  
Sadik H. Kassim ◽  
Robert O. Carpenter ◽  
James C. Yang ◽  
...  

Abstract We have treated 20 patients and administered 23 total T-cell infusions on a clinical trial of autologous T cells genetically modified to express a chimeric antigen receptor (CAR) targeting the B-cell antigen CD19. This is the largest reported clinical trial of anti-CD19-CAR T cells. The first 9 CAR-T-cell treatments have been reported (Kochenderfer et al. Blood 2010 and Blood 2012). This abstract communicates unreported results from 14 patients who received anti-CD19-CAR T cells produced with a new 10-day culture process. These patients did not receive exogenous interleukin-2. Of these 14 patients, 5 obtained complete remissions (CR), and 6 obtained partial remissions (PR), (see table).TablePatientAge/GenderMalignancyNumberof priortherapiesTotal cyclo-phosphamidedose(mg/kg)Number ofCAR+ T cellsinfused(X106/kg)Response(timeafter cellinfusion inmonths)156/MSMZL41205PR (20+)243/FPMBCL4605CR (19+)361/MCLL2604CR (16+)430/FPMBCL31202.5NE563/MCLL41202.5CR (10+)648/MCLL1602.5CR (7+)742/MDLBCL5602.5CR (4+)844/FPMBCL10602.5PR (6+)938/MPMBCL31202.5SD (1)1057/FLow-grade NHL4601PR (4+)1158/FDLBCL from CLL13601PR (2)1260/FDLBCL3601SD (1+)1368/MCLL4601PR (2+)1443/MDLBCL2601PR (1+) The CAR used in this work is encoded by a gammaretrovirus and incorporates the variable regions of an anti-CD19 antibody, part of CD28, and part of CD3-zeta. A mean of 70.5% of the infused T cells expressed the CAR, and the infused cells produced cytokines and degranulated in a CD19-specific manner. Because prior chemotherapy has been shown to enhance the activity of adoptively-transferred T cells, patients received cyclophosphamide (total doses shown in table) plus fludarabine (25 mg/m2 daily for 5 days) before a single infusion of anti-CD19-CAR-transduced T cells. This is the first report of successful treatment of chemotherapy-refractory primary mediastinal B-cell lymphoma (PMBCL) and diffuse large B-cell lymphoma not otherwise specified (DLBCL) with anti-CD19-CAR T cells. All of the 8 treated patients with either PMBCL or DLBCL were chemotherapy-refractory, and 5 of these 8 patients obtained either a CR or PR on this trial. We defined chemotherapy-refractory as progression or no response 1 month after the end of the most recent chemotherapy. For example, Patient 2 had PMBCL that was refractory to 3 different chemotherapy regimens and that relapsed after radiation therapy. Patient 2 obtained a CR after infusion of anti-CD19 CAR T cells and remains in CR 19 months post-infusion. Blood B-cell depletion lasting more than 3 months occurred in 3 of 3 evaluable patients. Most patients were not evaluable for B-cell depletion due to B-cell depletion by prior treatments. One patient died suddenly of unknown etiology 16 days after infusion of CAR T cells. Acute toxicities including fever, hypotension, and delirium occurred after infusion of anti-CD19-CAR T cells. The toxicities resolved in less than 3 weeks after the cell infusion and were temporally associated with elevated serum interleukin-6 and interferon gamma levels in most patients. Peak blood levels of cells containing the CAR gene ranged from 2.3% to 66.5% of blood mononuclear cells. These results demonstrate the feasibility of treating patients with chemotherapy-refractory B-cell malignancies by using autologous anti-CD19 CAR T cells. The numerous remissions obtained should encourage further development of this approach. SMZL, splenic marginal zone lymphoma; PMBCL, primary mediastinal B-cell lymphoma; CLL, chronic lymphocytic leukemia; DLBCL, diffuse large B-cell lymphoma not otherwise specified. CR, complete remission; NE, not evaluable; PR, partial remission; SD, stable disease. (+) indicates an ongoing response. Disclosures: Rosenberg: Kite Pharma: Research Funding.


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