scholarly journals Durable Clinical Responses in Heavily Pretreated Patients with Relapsed/Refractory Multiple Myeloma: Updated Results from a Multicenter Study of bb2121 Anti-Bcma CAR T Cell Therapy

Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 740-740 ◽  
Author(s):  
Jesus G. Berdeja ◽  
Yi Lin ◽  
Noopur Raje ◽  
Nikhil Munshi ◽  
David Siegel ◽  
...  

Abstract Introduction: Chimeric antigen receptor (CAR) T cell therapies have demonstrated robust and sustained clinical responses in several hematologic malignancies. Data suggest that achieving acceptable benefit:risk profiles depends on several factors, including the specificity of the antigen target and characteristics of the CAR itself, including on-target, off-tumor activity.To test the safety and efficacy of CAR T cells in relapsed and/or refractory multiple myeloma (RRMM), we have designed a second-generation CAR construct targeting B cell maturation antigen (BCMA) to redirect T cells to MM cells. BCMA is a member of the tumor necrosis factor superfamily that is expressed primarily by malignant myeloma cells, plasma cells, and some mature B cells. bb2121 consists of autologous T cells transduced with a lentiviral vector encoding a novel CAR incorporating an anti-BCMA scFv, a 4-1BB costimulatory motif and a CD3-zeta T cell activation domain. Methods: CRB-401 (NCT02658929) is a multi-center phase 1 dose escalation trial of bb2121 in patients with RRMM who have received ≥ 3 prior regimens, including a proteasome inhibitor and an immunomodulatory agent, or are double-refractory, and have ≥ 50% BCMA expression on malignant cells. Peripheral blood mononuclear cells are collected via leukapheresis and shipped to a central facility for transduction, expansion, and release testing prior to being returned to the site for infusion. Patients undergo lymphodepletion with fludarabine (30 mg/m2) and cyclophosphamide (300 mg/m2) daily for 3 days then receive 1 infusion of bb2121. The study follows a standard 3+3 design with planned dose levels of 50, 150, 450, 800, and 1,200 x 106 CAR+ T cells. The primary outcome measure is incidence of adverse events (AEs), including dose-limiting toxicities (DLTs). Additional outcome measures were quality and duration of clinical response assessed according to the IMWG Uniform Response Criteria for Multiple Myeloma, evaluation of minimal residual disease (MRD), overall and progression-free survival, quantification of bb2121 in blood, and quantification of circulating soluble BCMA over time. Results: Asof May 4, 2017, 21 patients (median 58 [37 to 74] years old) with a median of 5 (1 to 16) years since MM diagnosis, had been infused with bb2121, and 18 patients were evaluable for initial (1-month) clinical response. Patients had a median of 7 prior lines of therapy (range 3 to 14), all with prior autologous stem cell transplant; 67% had high-risk cytogenetics. Fifteen of 21 (71%) had prior exposure to, and 6 of 21 (29%) were refractory to 5 prior therapies (Bort/Len/Car/Pom/Dara). Median follow-up after bb2121 infusion was 15.4 weeks (range 1.4 to 54.4 weeks). As of data cut-off, no DLTs and no treatment-emergent Grade 3 or higher neurotoxicities similar to those reported in other CAR T clinical studies had been observed. Cytokine release syndrome (CRS), primarily Grade 1 or 2, was reported in 15 of 21 (71%) patients: 2 patients had Grade 3 CRS that resolved in 24 hours and 4 patients received tocilizumab, 1 with steroids, to manage CRS. CRS was more common in the higher dose groups but did not appear related to tumor burden. One death on study, due to cardiopulmonary arrest more than 4 months after bb2121 infusion in a patient with an extensive cardiac history, was observed while the patient was in sCR and was assessed as unrelated to bb2121. The overall response rate (ORR) was 89% and increased to 100% for patients treated with doses of 150 x 106 CAR+ T cells or higher. No patients treated with doses of 150 x 106 CAR+ T cells or higher had disease progression, with time since bb2121 between 8 and 54 weeks (Table 1). MRD negative results were obtained in all 4 patients evaluable for analysis. CAR+ T cell expansion has been demonstrated consistently and 3 of 5 patients evaluable for CAR+ cells at 6 months had detectable vector copies. A further 5 months of follow up on reported results and initial data from additional patients will be presented. Conclusions: bb2121 shows promising efficacy at dose levels above 50 x 106 CAR+ T cells, with manageable CRS and no DLTs to date. ORR was 100% at these dose levels with 8 ongoing clinical responses at 6 months and 1 patient demonstrating a sustained response beyond one year. These initial data support the potential of CAR T therapy with bb2121 as a new treatment paradigm in RRMM. CT.gov study NCT02658929, sponsored by bluebird bio and Celgene Disclosures Berdeja: Teva: Research Funding; Janssen: Research Funding; Novartis: Research Funding; Abbvie: Research Funding; Celgene: Research Funding; BMS: Research Funding; Takeda: Research Funding; Vivolux: Research Funding; Amgen: Research Funding; Constellation: Research Funding; Bluebird: Research Funding; Curis: Research Funding. Siegel: Celgene, Takeda, Amgen Inc, Novartis and BMS: Consultancy, Speakers Bureau; Merck: Consultancy. Jagannath: MMRF: Speakers Bureau; Bristol-Meyers Squibb: Consultancy; Merck: Consultancy; Celgene: Consultancy; Novartis: Consultancy; Medicom: Speakers Bureau. Turka: bluebird bio: Employment, Equity Ownership. Lam: bluebird bio: Employment, Equity Ownership. Hege: Celgene Corporation: Employment, Equity Ownership. Morgan: bluebird bio: Employment, Equity Ownership, Patents & Royalties. Quigley: bluebird bio: Employment, Equity Ownership, Patents & Royalties. Kochenderfer: Bluebird bio: Research Funding; N/A: Patents & Royalties: I have multiple patents in the CAR field.; Kite Pharma: Research Funding.

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1921-1921 ◽  
Author(s):  
Henia Dar ◽  
Daniel Henderson ◽  
Zinkal Padalia ◽  
Ashley Porras ◽  
Dakai Mu ◽  
...  

Abstract Autologous CAR-T cells targeting BCMA have induced robust and durable responses in patients with relapsed/refractory multiple myeloma. However, autologous cell therapies face several challenges which will likely limit the number of patients that will have access to these therapies. These limitations include manufacturing failure rates, wait time and supply constraints in addition to other factors such as reimbursement. Allogeneic CAR-T cells can potentially overcome these access challenges, and may have several other advantages over autologous therapies. Allogeneic CAR-T cells are derived from robust healthy donor T cells through a batch manufacturing process, which may result in a highly consistent product with greater potency and enable better safety management. Here we show further development and preclinical data for CTX120, an allogeneic "off the shelf" CAR-T cell targeting BCMA. CTX120 is produced using the CRISPR/Cas9 system to eliminate TCR and MHC class I, coupled with specific insertion of the CAR at the TRAC locus. CTX120 shows consistent and high percent CAR expression from this controlled insertion and exhibits target-specific cytotoxicity and cytokine secretion in response to BCMA positive cell lines. CTX120 CAR-T cells retain their cytotoxic capacity over multiple in vitro re-challenges, demonstrating durable potency and lack of exhaustion. In mouse models of multiple myeloma, CTX120 showed typical CAR-T persistence and eliminated tumors completely, resulting in long-term survival as compared to untreated animals. These data support the ongoing development of CTX120 for treatment of patients with multiple myeloma and further demonstrate the potential for our CRISPR/Cas9 engineered allogeneic CAR-T platform to generate potent CAR-T cells targeting different tumor antigens. Disclosures Dar: CRISPR Therapeutics: Employment, Equity Ownership. Henderson:CRISPR Therapeutics: Employment, Equity Ownership. Padalia:CRISPR Therapeutics: Employment, Equity Ownership. Porras:CRISPR Therapeutics: Employment, Equity Ownership. Mu:CRISPR Therapeutics: Employment, Equity Ownership. Kyungah:CRISPR Therapeutics: Employment, Equity Ownership. Police:CRISPR Therapeutics: Employment, Equity Ownership. Kalaitzidis:CRISPR Therapeutics: Employment, Equity Ownership. Terrett:CRISPR Therapeutics: Employment, Equity Ownership. Sagert:CRISPR Therapeutics: Employment, Equity Ownership.


Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 742-742 ◽  
Author(s):  
Eric L Smith ◽  
Sham Mailankody ◽  
Arnab Ghosh ◽  
Reed Masakayan ◽  
Mette Staehr ◽  
...  

Abstract Patients with relapsed/refractory MM (RRMM) rarely obtain durable remissions with available therapies. Clinical use of BCMA targeted CAR T cell therapy was first reported in 12/2015 for RRMM, and based on small numbers, preliminary results appear promising. Given that host immune anti-murine CAR responses have limited the efficacy of repeat dosing (Turtle C. Sci Trans Med 2016), our goal was to develop a human BCMA targeted CAR T cell vector for clinical translation. We screened a human B cell derived scFv phage display library containing 6x1010 scFvs with BCMA expressing NIH 3T3 cells, and validated results on human MM cell lines. 57 unique and diverse BCMA specific scFvs were identified containing light and heavy chain CDR's each covering 6 subfamilies, with HCDR3 length ranges from 5-18 amino acids. 17 scFvs met stringent specificity criteria, and a diverse set was cloned into CAR vectors with either a CD28 or a 4-1BB co-stimulatory domain. Donor T cells transduced with BCMA targeted CAR vectors that conveyed particularly desirable properties over multiple in vitro assays, including: cytotoxicity on human MM cell lines at low E:T ratios (>90% lysis, 1:1, 16h), robust proliferation after repeat antigen stimulation (up to 700 fold, stimulation q3-4d for 14d), and active cytokine profiling, were selected for in vivo studies using a marrow predominant human MM cell line model in NSG mice. A single IV injection of CAR T cells, either early (4d) or late (21d) after MM engraftment was evaluated. In both cases survival was increased when treated with BCMA targeted CAR T cells vs CD19 targeted CAR T cells (median OS at 60d NR vs 35d p<0.05). Tumor and CAR T cells were imaged in vivo by taking advantage of luciferase constructs with different substrates. Results show rapid tumor clearance, peak (>10,000 fold) CAR T expansion at day 6, followed by contraction of CAR T cells after MM clearance, confirming the efficacy of the anti-BCMA scFv/4-1BB containing construct. Co-culture with primary cells from a range of normal tissues did not activate CAR T cells as noted by a lack of IFN release. Co-culture of 293 cells expressing this scFv with those expressing a library of other TNFRSF or Ig receptor members demonstrated specific binding to BCMA. GLP toxicity studies in mice showed no unexpected adverse events. We generated a retroviral construct for clinical use including a truncated epithelial growth factor receptor (EGFRt) elimination gene: EGFRt/hBCMA-41BBz. Clinical investigation of this construct is underway in a dose escalation, single institution trial. Enrollment is completed on 2/4 planned dose levels (DL). On DL1 pts received cyclophosphamide conditioning (3g/m2 x1) and 72x106 mean CAR+ T cells. On DL2 pts received lower dose cyclophosphamide/fludarabine (300/30 mg/m2 x3) and 137x106 mean CAR+ T cells. All pts screened for BCMA expression by IHC were eligible. High risk cytogenetics were present in 4/6 pts. Median prior lines of therapy was 7; all pts had IMiD, PI, high dose melphalan, and CD38 directed therapies. With a data cut off of 7/20/17, 6 pts are evaluable for safety. There were no DLT's. At DL1, grade 1 CRS, not requiring intervention, occurred in 1/3 pts. At DL2, grade 1/2 CRS occurred in 2/3 pts; both received IL6R directed Tocilizumab (Toci) with near immediate resolution. In these 2 pts time to onset of fever was a mean 2d, Tmax was 39.4-41.1 C, peak CRP was 25-27mg/dl, peak IL6 level pre and post Toci were 558-632 and 3375-9071 pg/ml, respectively. Additional serum cytokines increased >10 fold from baseline in both pts include: IFNg, GM CSF, Fractalkine, IL5, IL8, and IP10. Increases in ferritin were limited, and there were no cases of hypofibrinogenemia. There were no grade 3-5 CRS and no neurotoxicities or cerebral edema. No pts received steroids or Cetuximab. Median time to count recovery after neutropenia was 10d (range 6-15d). Objective responses by IMWG criteria after a single dose of CAR T cells were observed across both DLs. At DL1, of 3 pts, responses were 1 VGPR, 1 SD, and 1 pt treated with baseline Mspike 0.46, thus not evaluable by IMWG criteria, had >50% reduction in Mspike, and normalization of K/L ratio. At DL2, 2/2 pts had objective responses with 1 PR and 1 VGPR (baseline 95% marrow involvement); 1 pt is too early to evaluate. As we are employing a human CAR, the study was designed to allow for an optional second dose in pts that do not reach CR. We have treated 2 pts with a second dose, and longer follow up data is pending. Figure 1 Figure 1. Disclosures Smith: Juno Therapeutics: Membership on an entity's Board of Directors or advisory committees, Patents & Royalties: BCMA targeted CAR T cells, Research Funding. Almo: Cue Biopharma: Other: Founder, head of SABequity holder; Institute for Protein Innovation: Consultancy; AKIN GUMP STRAUSS HAUER & FELD LLP: Consultancy. Wang: Eureka Therapeutics Inc.: Employment, Equity Ownership. Xu: Eureka Therapeutics, Inc: Employment, Equity Ownership. Park: Amgen: Consultancy. Curran: Juno Therapeutics: Research Funding; Novartis: Consultancy. Dogan: Celgene: Consultancy; Peer Review Institute: Consultancy; Roche Pharmaceuticals: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees. Liu: Eureka Therpeutics Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Brentjens: Juno Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 488-488 ◽  
Author(s):  
Nina Shah ◽  
Melissa Alsina ◽  
David S Siegel ◽  
Sundar Jagannath ◽  
Deepu Madduri ◽  
...  

Abstract Introduction: Immunomodulatory chimeric antigen receptor (CAR) T cell therapy directed against B-cell maturation antigen (BCMA) has shown promising results for the treatment of relapsed refractory multiple myeloma (RRMM) in several phase 1 clinical studies in patients with advanced disease. Persistence of CAR T cells post infusion may be one determinant of duration of response. bb21217 is a next-generation anti-BCMA CAR T cell therapy based on investigational therapy bb2121 (Friedman 2018, Hum Gene Ther 29:585). It uses the same scFv, 4-1BB costimulatory motif and CD3-zeta T cell activation domain as bb2121 with the addition of phosphoinositide 3 kinase inhibitor bb007 during ex vivo culture to enrich the drug product for T cells displaying a memory-like phenotype. Evidence suggests that CAR T cells with this phenotype may be more persistent and more potent than unselected CAR T cells. CRB-402 is a first-in-human clinical study of bb21217 in patients with RRMM designed to assess the safety, pharmacokinetics, efficacy and duration of effect of bb21217. Methods: CRB-402 (NCT03274219) is an ongoing, multi-center phase 1 dose escalation trial of bb21217 in approximately 50 patients with RRMM who have received ≥ 3 prior regimens, including a proteasome inhibitor and an immuno-modulatory agent, or are double-refractory. During dose escalation, enrollment is restricted to patients with ≥ 50% BCMA expression by IHC on malignant plasma cells. Peripheral blood mononuclear cells are collected via leukapheresis and sent to a central facility for transduction, expansion and release testing prior to being returned to the site for infusion. Patients undergo lymphodepletion with fludarabine (30 mg/m2) and cyclophosphamide (300 mg/m2) daily for 3 days, then receive bb21217 as a single infusion. Planned dose levels are 150, 450, 800, and 1,200 x 106 CAR+ T cells. The primary outcome measure is incidence of adverse events (AEs), including dose-limiting toxicities (DLTs). Additional outcome measures are quality and duration of clinical response assessed according to the IMWG Uniform Response Criteria for MM, evaluation of minimal residual disease (MRD), progression-free and overall survival, and quantification of CAR+ cells in blood. Results: Asof June 15, 2018, 8 patients (median age 64 [min;max 54 to 70]) have received bb21217. All patients to date received a dose of 150 x 106 CAR+ T cells. Four had high tumor burden, defined as ≥ 50% bone marrow plasma cells pre-infusion. Patients had a median of 9 (min;max 4 to 17) prior lines of therapy and 7/8 had prior autologous stem cell transplant; 50% had high-risk cytogenetics. Four of 8 (50%) had previously received Bort/Len/Car/Pom/Dara. Median follow-up after bb21217 infusion was 16 weeks (2 to 27 weeks) and 7 patients were evaluable for initial (1-month) clinical response. As of data cut-off, 5 of 8 patients developed cytokine release syndrome (CRS; 1 Grade 1, 3 Grade 2, 1 Grade 3) and responded to supportive care or tocilizumab. This included 1 patient with high tumor burden who experienced DLTs consisting of grade 3 CRS and grade 4 encephalopathy with signs of posterior reversible encephalopathy syndrome on MRI. This patient received tocilizumab, corticosteroids and cyclophosphamide, improved neurologically and achieved a sCR. Following this event, the dose escalation cohort was divided into two groups based on tumor burden and dosing continued at 150x106 CAR+ T cells. No deaths occurred. With 1 to 6 months since treatment, 6 of 7 patients had demonstrated clinical response per IMWG criteria: currently 1 sCR, 3 VGPR, 2 PR. MRD negative results at 10-5 nucleated cells were obtained by next-generation sequencing in 3 of 3 evaluable responders. Robust CAR+ T cell expansion during the first 30 days was observed in 7 of 7 evaluable patients. Two of 2 patients evaluable at 6 months had detectable CAR vector copies. Conclusions: Early efficacy results with bb21217 CAR T therapy in RRMM at a dose of 150 x 106 CAR+ T cells are encouraging, with 6 of 7 patients demonstrating clinical responses. The adverse events observed to date are consistent with known toxicities of CAR T therapies. CAR+ T cells were measurable at 6 months post treatment in both evaluable patients. Enrollment in the study is ongoing; longer follow-up and data in more patients will establish whether treatment with bb21217 results in sustained CAR+ T cell persistence and responses. Disclosures Shah: Kite: Consultancy; Indapta Therapeutics: Consultancy; University of California San Francisco: Employment; Nekktar: Consultancy; Teneobio: Consultancy; Sanofi: Consultancy; Janssen: Research Funding; Indapta Therapeutics: Equity Ownership; Amgen: Consultancy; Bluebird: Research Funding; Celgene: Research Funding; Bristol Myers Squibb: Consultancy; Takeda: Consultancy; Sutro Biopharma: Research Funding; Nkarta: Consultancy. Siegel:Takeda: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Karyopharm: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Merck: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau. Jagannath:Multiple Myeloma Research Foundation: Speakers Bureau; Merck: Consultancy; Novartis: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy; Medicom: Speakers Bureau. Kaufman:Karyopharm: Other: data monitoring committee; BMS: Consultancy; Janssen: Consultancy; Abbvie: Consultancy; Roche: Consultancy. Turka:bluebird bio, Inc: Employment, Equity Ownership. Lam:bluebird bio, Inc: Employment, Equity Ownership. Massaro:bluebird bio, Inc: Employment, Equity Ownership. Hege:Celgene Corporation: Employment, Equity Ownership, Patents & Royalties: multiple; Mersana: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; SITC: Membership on an entity's Board of Directors or advisory committees; Arcus Biosicences: Membership on an entity's Board of Directors or advisory committees. Petrocca:bluebird bio, Inc: Employment, Equity Ownership. Berdeja:Glenmark: Research Funding; Novartis: Research Funding; Genentech: Research Funding; Janssen: Research Funding; Bristol-Myers Squibb: Research Funding; Bluebird: Research Funding; Amgen: Research Funding; Celgene: Research Funding; Poseida Therapeutics, Inc.: Research Funding; Takeda: Research Funding; Teva: Research Funding; Sanofi: Research Funding. Raje:AstraZeneca: Research Funding; Takeda: Consultancy; Merck: Consultancy; Janssen: Consultancy; Celgene: Consultancy; BMS: Consultancy; Amgen Inc.: Consultancy; Research to Practice: Honoraria; Medscape: Honoraria.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3184-3184 ◽  
Author(s):  
Caitlin L. Costello ◽  
Tara K. Gregory ◽  
Syed Abbas Ali ◽  
Jesus G. Berdeja ◽  
Krina K. Patel ◽  
...  

P-BCMA-101 is a novel chimeric antigen receptor (CAR)-T cell product targeting B Cell Maturation Antigen (BCMA). P-BCMA-101 is produced using the piggyBac® (PB) DNA Modification System instead of the viral vector that is used with most CAR-T cells, requiring only plasmid DNA and mRNA. This makes it less costly and produces cells with a high percentage of the favorable T stem cell memory phenotype (TSCM). The higher cargo capacity of PB permits the incorporation of multiple genes in addition to CAR(s), including a safety switch allowing for rapid CAR-T cell elimination with a small molecule drug infusion in patients if desired, and a selection gene allowing for enrichment of CAR+ cells. Rather than using a traditional antibody-based binder, P-BCMA-101 has a Centyrin™ fused to a CD3ζ/4-1BB signaling domain. Centyrins are fully human proteins with high specificity and a large range of binding affinities, but are smaller, more stable and potentially less immunogenic than traditional scFv. Cumulatively, these features are predicted to result in a greater therapeutic index. A Phase 1, 3+3 dose escalation from 0.75 to 15 x 106 P-BCMA-101 CAR-T cells/kg (RP2D 6-15 x 106 cells/kg) was conducted in patients with r/r MM (Blood 2018 132:1012) demonstrating excellent efficacy and safety of P-BCMA-101, including notably low rates and grades of CRS and neurotoxicity (maximum Grade 2 without necessitating ICU admission, safety switch activation or other aggressive measures). These results supported FDA RMAT designation and initiation of a pivotal Phase 2 study. A Phase 2 pivotal portion of this study has recently been designed and initiated (PRIME; NCT03288493) in r/r MM patients who have received at least 3 prior lines of therapy. Their therapy must have contained a proteasome inhibitor, an IMiD, and CD38 targeted therapy with at least 2 of the prior lines in the form of triplet combinations. They must also have undergone ≥2 cycles of each line unless PD was the best response, refractory to the most recent line of therapy, and undergone autologous stem cell transplant or not be a candidate. Patients are required to be >=18 years old, have measurable disease by International Myeloma Working Group criteria (IMWG; Kumar 2016), adequate vital organ function and lack significant autoimmune, CNS and infectious diseases. No pre-specified level of BCMA expression is required, as this has not been demonstrated to correlate with clinical outcomes for P-BCMA-101 and other BCMA-targeted CAR-T products. Interestingly, unlike most CAR-T products patients may receive P-BCMA-101 after prior CAR-T cells or BCMA targeted agents, and may be multiply infused with P-BCMA-101. Patients are apheresed to harvest T cells, P-BCMA-101 is then manufactured and administered to patients as a single intravenous (IV) dose (6-15 x 106 P-BCMA-101 CAR-T cells/kg) after a standard 3-day cyclophosphamide (300 mg/m2/day) / fludarabine (30 mg/m2/day) conditioning regimen. One hundred patients are planned to be treated with P-BCMA-101. Uniquely, given the safety profile demonstrated during Phase 1, no hospital admission is required and patients may be administered P-BCMA-101 in an outpatient setting. The primary endpoints are safety and response rate by IMWG criteria. With a 100-subject sample, the Phase 2 part of the trial will have 90% power to detect a 15-percentage point improvement over a 30% response rate (based on that of the recently approved anti-CD38 antibody daratumumab), using an exact test for a binomial proportion with a 1-sided 0.05 significance level. Multiple biomarkers are being assessed including BCMA and cytokine levels, CAR-T cell kinetics, immunogenicity, T cell receptor diversity, CAR-T cell and patient gene expression (e.g. Nanostring) and others. Overall, the PRIME study is the first pivotal study of the unique P-BCMA-101 CAR-T product, and utilizes a number of novel design features. Studies are being initiated in combination with approved therapeutics and earlier lines of therapy with the intent of conducting Phase 3 trials. Funding by Poseida Therapeutics and the California Institute for Regenerative Medicine (CIRM). Disclosures Costello: Takeda: Honoraria, Research Funding; Janssen: Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Gregory:Poseida: Research Funding; Celgene: Speakers Bureau; Takeda: Speakers Bureau; Amgen: Speakers Bureau. Ali:Celgene: Research Funding; Poseida: Research Funding. Berdeja:Amgen Inc, BioClinica, Celgene Corporation, CRISPR Therapeutics, Bristol-Myers Squibb Company, Janssen Biotech Inc, Karyopharm Therapeutics, Kite Pharma Inc, Prothena, Servier, Takeda Oncology: Consultancy; AbbVie Inc, Amgen Inc, Acetylon Pharmaceuticals Inc, Bluebird Bio, Bristol-Myers Squibb Company, Celgene Corporation, Constellation Pharma, Curis Inc, Genentech, Glenmark Pharmaceuticals, Janssen Biotech Inc, Kesios Therapeutics, Lilly, Novartis, Poseida: Research Funding; Poseida: Research Funding. Patel:Oncopeptides, Nektar, Precision Biosciences, BMS: Consultancy; Takeda, Celgene, Janssen: Consultancy, Research Funding; Poseida Therapeutics, Cellectis, Abbvie: Research Funding. Shah:University of California, San Francisco: Employment; Genentech, Seattle Genetics, Oncopeptides, Karoypharm, Surface Oncology, Precision biosciences GSK, Nektar, Amgen, Indapta Therapeutics, Sanofi: Membership on an entity's Board of Directors or advisory committees; Indapta Therapeutics: Equity Ownership; Celgene, Janssen, Bluebird Bio, Sutro Biopharma: Research Funding; Poseida: Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Nkarta: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kite: Consultancy, Membership on an entity's Board of Directors or advisory committees; Teneobio: Consultancy, Membership on an entity's Board of Directors or advisory committees. Ostertag:Poseida Therapeutics, Inc.: Employment, Equity Ownership. Martin:Poseida Therapeutics, Inc.: Employment, Equity Ownership. Ghoddusi:Poseida Therapeutics, Inc.: Employment, Equity Ownership. Shedlock:Poseida Therapeutics, Inc.: Employment, Equity Ownership. Spear:Poseida Therapeutics, Inc.: Employment, Equity Ownership. Orlowski:Poseida Therapeutics, Inc.: Research Funding. Cohen:Poseida Therapeutics, Inc.: Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1856-1856 ◽  
Author(s):  
Damian J. Green ◽  
Margot Pont ◽  
Andrew J. Cowan ◽  
Gabriel O Cole ◽  
Blythe Duke Sather ◽  
...  

Introduction: The adoptive transfer of B-Cell Maturation Antigen (BCMA) chimeric antigen receptor (CAR) T cells is demonstrating early promise in multiple myeloma [MM], however durable responses remain elusive and most studies report >50% of patients relapsing within 18 months of receiving CAR-T cell therapy. The mechanism of relapse is likely the consequence of multiple factors including the variable distribution of BCMA on tumor cells, allowing cells with low antigen density to escape. Initial target density, receptor downregulation and the emergence of antigen loss variants have all been implicated in relapse following CAR-T cells directed against CD22 and CD19. Reduced or absent BCMA expression may similarly be linked to relapse in MM. We have previously demonstrated that BCMA cleavage by the γ-secretase complex reduces ligand density for CAR-T cell recognition, and that a small molecule γ-secretase inhibitor (GSI) markedly increases surface BCMA levels in a dose-dependent fashion while improving CAR-T cell recognition in preclinical models. Methods and Results: In a phase I first-in-human study (NCT03338972) employing a CAR-T cell construct encoding a fully human BCMA scFv and 4-1BB/CD3z, rapid and deep objective responses at CAR-T cell doses starting at 5 x 107 have been observed. All patients had bone marrow (BM) involvement at baseline (mean 42.5 % CD138+ by IHC) and 14/15 had no detectable disease in the BM 28 days after therapy. One patient with comparatively very low BCMA expression (BCMA antibody binding capacity [ABC; QuantiBRITE] = 269; 16.9% of the malignant plasma cells (PCs) BCMA+ by flow cytometry) was the only subject with persistent tumor cells in the BM 28 days after therapy. Despite complete BM responses in all remaining patients, late relapses have occurred. Differences in the BCMA expression level on tumor cells prior to CAR-T cells between long term responders and those with relapse are evident. Among the 12 subjects with at least 3 months of follow up, those remaining in remission (median 12 months, range 3-16; data cut off 7/15/19) demonstrated a median pre-treatment BCMA ABC of 1761 (range 781-2922, n=5), in contrast patients with relapse (mean of 7.3 months, range 2-12) had a median pre-treatment BCMA ABC of 920 (range 260-1540, n=7). Six patients with a pretreatment mean ABC of 919 (range 260-1540) had BM evaluable for BCMA expression at relapse and the mean ABC decreased to 304 (range 121-519). The percent PCs expressing BCMA decreased from 77.5% (range 13 - 99.8) to 30% (range 10.4-60.4). The impact of gamma secretase inhibition on BCMA expression was assessed on BM cells obtained from a patient relapsing after BCMA CAR-T cells. At relapse a 9.5-fold decrease in ABC from baseline was observed. The cells were cultured for 5 hours in the presence of GSI (JSMD194) at a concentration of 1mM, which is readily achievable by oral administration. A significant increase in BCMA antigen expression was observed (ABC=917). The impact of modulating BCMA expression on tumor cells by concurrently administering an oral GSI with CAR-T cells is being explored in a phase one clinical trial (NCT03502577). In this setting, the GSI has increased BCMA expression when low level residual BCMA was observed following relapse after prior BCMA therapy failure. Two patients have been evaluated for response to an JSMD194 after failing other BCMA targeted agents. One received a prior BCMA CAR-T cell product and after relapse demonstrated a BCMA ABC of 769. Target expression increased in this patient almost nine-fold to 6828 (ABC) after three oral doses of JSMD194. A second patient had a BCMA ABC of 666 after failing a BCMA bispecific T cell engager. BCMA density increased over 14-fold to 9583 after GSI. Comprehensive data from the combination GSI and BCMA CAR-T cell trial are being reported separately. Conclusion: Pretreatment BCMA target density quantified with a uniform flow cytometry method of measurement and performed on all patients enrolled on a single center BCMA CAR-T cell clinical trial is associated with the durability of response. Further, BCMA expression can be significantly increased following GSI exposure in patients evidencing low BCMA ABC at baseline or when downregulation is the consequence of prior BCMA targeting therapy. The capacity for GSIs to increase BCMA target density and decrease soluble BCMA levels is a promising approach to be exploited in clinical trials. Disclosures Green: Juno Therapeutics: Consultancy, Patents & Royalties, Research Funding; Celgene: Consultancy; GSK: Consultancy; Seattle Genetics: Research Funding; Cellectar: Research Funding. Pont:Fred Hutchinson Cancer Research Center: Other: Inventor on a patent. Cowan:Sanofi: Consultancy; Juno: Research Funding; Abbvie: Research Funding; Janssen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Cellectar: Consultancy. Sather:Lyell Immunopharma: Employment, Equity Ownership. Blake:Celgene: Employment, Equity Ownership. Works:Celgene: Employment, Equity Ownership. Maloney:Juno Therapeutics: Honoraria, Patents & Royalties: patients pending , Research Funding; A2 Biotherapeutics: Honoraria, Other: Stock options ; BioLine RX, Gilead,Genentech,Novartis: Honoraria; Celgene,Kite Pharma: Honoraria, Research Funding. Riddell:Juno Therapeutics: Equity Ownership, Patents & Royalties, Research Funding; Adaptive Biotechnologies: Consultancy; Lyell Immunopharma: Equity Ownership, Patents & Royalties, Research Funding. OffLabel Disclosure: Oral Gamma Secretase Inhibitor. Purpose is to increase expression of B Cell Maturation Antigen


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3230-3230 ◽  
Author(s):  
Lekha Mikkilineni ◽  
Elisabet E. Manasanch ◽  
Norris Lam ◽  
Danielle Vanasse ◽  
Jennifer N. Brudno ◽  
...  

Chimeric antigen receptor (CAR) T cells expressing B-cell maturation antigen (BCMA) can target and kill multiple myeloma (MM). BCMA was chosen as a target for MM because it is expressed by almost all cases of MM but has a restricted expression pattern on normal cells. CAR antigen-recognition domains made up of monoclonal antibody-derived, single-chain-variable fragments (scFv) are potentially immunogenic. To reduce the risk of recipient immune responses against CAR T cells, we used the sequence of a novel anti-BCMA, fully-human, heavy-chain-only binding domain designated FHVH33. The FHVH33 binding domain sequence was from TeneoBio, Inc. FHVH33 is smaller than a scFv. FHVH33 lacks the light chain, artificial linker sequence, and 2 associated junctions of a scFv, so it is predicted to be less immunogenic than a scFv, especially murine-derived scFvs. We constructed a CAR incorporating FHVH33, CD8α hinge and transmembrane domains, a 4-1BB costimulatory domain, and a CD3ζ T-cell activation domain. The CAR, FHVH33-CD8BBZ, is encoded by a γ-retroviral vector. FHVH33-CD8BBZ-expressing T cells (FHVH-BCMA-T) exhibited a full range of T-cell functions in vitro and eliminated tumors and disseminated malignancy in mice (Lam et al, Blood (ASH abstract) 2017 vol 130: 504). We are conducting the first clinical trial of FHVH-BCMA-T. Patients receive conditioning chemotherapy on days -5 to -3 with 300 mg/m2 of cyclophosphamide and 30 mg/m2 of fludarabine followed by infusion of FHVH-BCMA-T on day 0. This dose-escalation trial has 5 planned dose levels (DL). Twelve patients have received FHVH-BCMA-T on 3 DLs, 0.75x106, 1.5x106 and 3x106 CAR+ T cells/kg of bodyweight. Three patients were enrolled on the trial but not treated. The median age of patients enrolled was 63 (range 52-70); patients received a median of 6 lines of anti-myeloma therapy (range 3-10) prior to treatment with FHVH-BCMA-T. Ten patients out of 12 patients have achieved objective responses (OR). Five patients have obtained CRs or VGPRs to date. One patient achieved a partial remission (PR) 26 weeks after FHVH-BCMA-T infusion through a continued decrease in a measurable plasmacytoma. Five out of 7 patients who had myeloma with high-risk cytogenetics had an OR (Table). ORs occurred in patients with large soft-tissue plasmacytomas. Loss of BCMA expression on myeloma cells after treatment was documented in 2 patients. Two patients who developed progressive MM after CAR T-cell infusion had evidence of minimal residual disease in bone marrow 1-2 months post infusion of CAR T cells (patients 7,8). Eleven out of 12 patients had cytokine release syndrome (CRS); CRS grades ranged from 1-3 (Lee et al. Biol Blood Marrow Transplant 25 (2019) 625-638). The median peak C reactive protein (CRP) of the patients with CRS was 156.3 mg/L. Of 12 patients, 1 received the interleukin-6-receptor antagonist tocilizumab on day +6 to treat grade 3 CRS with hypotension requiring low-dose pressor therapy, grade 2 ejection fraction (EF) decrease and elevation of creatinine kinase (CK). All parameters returned to baseline by day +10. Patient 12 had a grade 3 decrease in EF which resolved by day +29. Two patients had grade 2 neurotoxicity that resolved without intervention: patient 3 had headaches, dysarthria and word-finding difficulties that resolved after 6 days while patient 6 had headaches on day +4. Patient 12 had grade 3 neurotoxicity with confusion on day +2; she was given dexamethasone with improvement in mental status the same day. After attaining a response, patient 6 died from influenza complications 6 weeks after FHVH-BCMA-T infusion. A median of 10.6% (range 1.1-46) of bone marrow T cells were CAR+ when assessed 14 days after FHVH-BCMA-T infusion. We assessed blood CAR+ cells by quantitative PCR. The median peak level of CAR+ cells was 76.5 cells/µl (range 3-347 cells/µl) and the median day post-infusion of peak blood CAR+ cell levels was 13 (range 9-14). The results from this phase 1 trial demonstrate that FHVH-BCMA-T cells can induce responses at low dose levels. Patients who had no CRS or low-grade CRS achieved objective responses. Toxicity was limited and reversible. Accrual to this trial continues. A maximum tolerated dose has not been determined yet. These results encourage further development of FHVH CAR-T. Table Disclosures Manasanch: Janssen: Honoraria; Sanofi: Honoraria; Takeda: Honoraria; Merck: Research Funding; Skyline Diagnostics: Research Funding; Sanofi: Research Funding; Quest Diagnostics: Research Funding; Celgene: Honoraria. Trinklein:Teneobio, Inc.: Employment, Equity Ownership. Buelow:Teneobio, Inc.: Employment, Equity Ownership. Kochenderfer:Kite and Celgene: Research Funding; Bluebird and CRISPR Therapeutics: Other: received royalties on licensing of his inventions. OffLabel Disclosure: Cyclophosphamide and fludarabine are used in combination for conditioning chemotherapy prior to CAR T-cell infusion


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4192-4192 ◽  
Author(s):  
Jeremy S. Abramson ◽  
Lia Palomba ◽  
Leo I Gordon ◽  
Matthew Lunning ◽  
Jon Arnason ◽  
...  

Abstract Background: Based on promising results seen in patients treated with CD19-directed CAR-T cells in relapsed or refractory (R/R) pediatric B-cell acute lymphoblastic leukemia (Gardner, ASCO 2016) and adult B-cell non-Hodgkin lymphoma (Turtle, ASCO 2016), we are conducting a multicenter phase 1 trial of JCAR017 in R/R diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) (ClinicalTrials.gov Identifier: NCT02631044). JCAR017 is a second-generation, CD19-directed CAR-T cell product of defined cellular composition consisting of a 1:1 ratio of CD8+:CD4+ CAR+ T cells. Methods: Patients with R/R DLBCL (de novo or transformed from indolent lymphoma), follicular lymphoma grade 3B, or MCL and adequate organ function are eligible. There was no minimum absolute lymphocyte count (ALC) requirement for apheresis and no test expansion required. Treatment includes lymphodepletion (fludarabine 30 mg/m2 and cyclophosphamide 300 mg/m2 daily for 3 days) and JCAR017 given 2-7 days post-lymphodepletion at a starting dose of 5 x 107 CAR+ T cells (DL1). Single-dose and two-dose schedules are being evaluated. Primary objectives include safety and pharmacokinetics (PK) of JCAR017 measured by flow cytometry and quantitative PCR. Secondary objectives include complete and overall response (CR, OR) rates and duration of response (DOR). Response is assessed using the Lugano (2014) criteria. Results: As of August 1, 2016, 39 patients have been enrolled and 28 patients apheresed. Fourteen patients have been treated, all at DL1. Eight were male and 6 female. Thirteen patients had DLBCL and 1 had MCL. Median age was 61 years (range 37-79) and median number of prior therapies was 5 (range 2-9). Ten patients had undergone prior transplant (7 autologous; 3 allogeneic). Of the 14 patients, there were no cases of severe cytokine release syndrome (sCRS); 3 patients had low grade CRS (21%) (2 grade 1; 1 grade 2) and none required treatment with tocilizumab. Two of the 14 treated patients (14%) had neurotoxicity: 1 grade 4 encephalopathy and 1 grade 4 seizure. Both were in patients with DLBCL and were dose-limiting toxicities. Two deaths were seen in the DLBCL group and were due to disease progression. Twelve patients had at least 1 post-treatment response assessment; 11 patients with DLBCL and 1 with MCL. The patient with MCL had progressive disease at day 29 (D29). In the DLBCL group, response rates were: 82% (9/11) OR, 73% (8/11) CR, 9% (1/11) PR and 18% (2/11) PD at the time of post-treatment assessment on D29. All but one patient who achieved a CR were in remission at the time of this data cut. One DLBCL patient in CR had a parenchymal brain lesion in the right temporal lobe that also completely resolved. Of note, this patient had no CRS or neurotoxicity associated with JCAR017 treatment. The PK profile of JCAR017 in the peripheral blood and bone marrow show cellular expansion in all patients with persistence out to at least 3 months in patients with adequate follow up. Exploratory biomarker analyses will be presented at the meeting along with updated clinical data. Conclusions: Treatment with the defined cellular composition product JCAR017 following lymphodepletion with fludarabine and cyclophosphamide results in high CR rates in patients with heavily pretreated DLBCL, including the first report of a CR in a patient with secondary CNS lymphoma. Observed toxicities are manageable and compare favorably to other reported CAR T-cell products. Disclosures Abramson: Gilead: Consultancy; Kite Pharma: Consultancy; Abbvie: Consultancy; Seattle Genetics: Consultancy. Gordon:Northwestern University: Patents & Royalties: Patent for gold nanoparticles pending. Lunning:Celgene: Consultancy; Bristol-Myer-Squibb: Consultancy; Pharmacyclics: Consultancy; Genentech: Consultancy; Juno: Consultancy; AbbVie: Consultancy; Gilead: Consultancy; TG Therapeutics: Consultancy; Spectrum: Consultancy. Arnason:Gilead: Consultancy. Forero-Torres:Genentech/Roche: Research Funding; Seattle Genetics: Research Funding; Juno: Research Funding; Incyte: Research Funding; Abbvie: Research Funding; Novartis: Research Funding; Pfizer: Research Funding. Albertson:Juno Therapeutics: Employment, Equity Ownership. Sutherland:Juno therapeutics: Employment. Xie:Juno Therapeutics: Employment, Equity Ownership. Snodgrass:Juno therapeutics: Employment. Siddiqi:Pharmacyclics, LLC, an AbbVie Company: Speakers Bureau; Janssen: Speakers Bureau; Seattle Genetics: Speakers Bureau; Kite pharma: Other: Funded travel, 1 day registration, and 1 night hotel stay for EHA2016 so I could present trial data there.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 957-957 ◽  
Author(s):  
Sham Mailankody ◽  
Myo Htut ◽  
Kelvin P. Lee ◽  
William Bensinger ◽  
Todd Devries ◽  
...  

Abstract Introduction: B-cell maturation antigen (BCMA) is expressed on malignant plasma cells and is an attractive therapeutic target for multiple myeloma. BCMA CAR T-cells, antibody drug conjugates and bispecific T-cell engagers have demonstrated substantial preclinical and clinical activity to date. JCARH125 is a BCMA-targeting CAR T product containing a lentiviral CAR construct with a fully human scFv, optimized spacer, 4-1BB co-stimulatory and CD3z activation domains. The construct has shown minimal tonic signaling and lack of inhibition by soluble BCMA. JCARH125 is generated using a manufacturing process developed to optimize various aspects, including increased consistency of cell health, in the drug product. Methods: EVOLVE (NCT03430011) is a multi-center, phase 1/2 trial of JCARH125 in patients with relapsed and/or refractory multiple myeloma, who have received 3 or more prior regimens, which must include autologous stem cell transplant, a proteasome inhibitor, immunomodulatory drug and an anti-CD38 monoclonal antibody, unless not a candidate (i.e. contraindicated) to receive one or more of the above treatments. Lymphodepleting chemotherapy (LDC) consisting of 3 days of fludarabine (30 mg/m2) and cyclophosphamide (300 mg/m2) is given 2 to 7 days prior to JCARH125 infusion. A single dose of JCARH125 is given on day 1. Dose escalation is determined using the modified toxicity probability interval 2 (mTPI-2). A minimum of 3 patients are evaluated at each dose level (DL). The first 2 DLs evaluated were 50 and 150x 106 CAR+ T cells. Additional DLs are planned, followed by an expansion at the recommended phase 2 dose (RP2D). The primary objectives of the phase 1 portion are safety and identifying a RP2D. Results: At the time of the July 12, 2018 data analysis, 19 patients have been enrolled (i.e. apheresed) and 13 patients dosed with JCARH125. Only one patient was unable to receive JCARH125, due to sepsis after LDC, leading to death before JCARH125 administration. Eight patients were evaluable for safety (≥ 1 mo follow-up). (n = 5 DL1; n = 3 DL2). Three patients (all from DL1) were evaluable for confirmed response (≥ 2 mo follow-up) per International Myeloma Working Group (IMWG) criteria. Data reported here are from these initial 8 patients. Median follow-up is 5 weeks (range 4 - 13 weeks). Median age is 53 years (range 36 - 66) with a median time from diagnosis of 4 years (range 2 - 12). Patients had received a median of 10 prior regimens (range 4 - 15). Of these 8 patients, 4 (50%) were refractory (no response or progression within 60 days of last therapy) to bortezomib, carfilzomib, lenalidomide, pomalidomide and an anti-CD38 monoclonal antibody. Seven of 8 (88%) had prior autologous stem cell transplant and 4 of 8 (50%) have IMWG high risk cytogenetics. As of the data cut, no DLTs have been observed at the first 2 DLs. Cytokine release syndrome (CRS), all grade 1 or 2, was observed in 6 of 8 (75%) patients. Median onset of CRS was 9 days (range 4 - 10) with a median duration of 4.5 days (range 2 - 19 days). None of the patients with grade 2 CRS required vasopressor support and only 1 patient received tocilizumab. No patients had grade ≥ 3 CRS. Three of 8 (38%) patients experienced neurologic adverse events (AE). Two patients had grade 1 events, and 1 had a grade 3 event (lethargy), which resolved within 24 hours after receiving steroids. Onset of neurologic AEs was 9,11 and 12 days with a duration of 2, 3 and 1 days respectively. Notably, the patient who experienced grade 3 neurotoxicity (NT), developed secondary plasma cell leukemia (PCL) just prior to receiving LDC. All 8 patients have evidence of objective response (≥ MR), including the patient with secondary PCL. 3 patients, all treated at DL1 (50 x 106 CAR+ T-cells), have confirmed responses (1 PR, 2 sCR) with the remainder unconfirmed (1 CR, 2 VGPR, 1 PR, 1 MR). As of the data cut, no patients have progressed. Additional clinical and translational data on at least 30 patients and additional follow up of at least 4 months will be available at time of presentation. Conclusion: At initial lower dose levels, JCARH125 showed an acceptable safety profile with no DLTs reported thus far. Incidence of grade ≥ 3 NT was low and no grade ≥ 3 CRS has occurred with clear clinical activity. Although durability of response and response rate in a greater number of patients remain to be determined, early experience with JCARH125 support a favorable risk-benefit profile and rapid clinical development. Disclosures Mailankody: Takeda: Research Funding; Janssen: Research Funding; Physician Education Resource: Honoraria; Juno: Research Funding. Bensinger:celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; amgen: Speakers Bureau; Takeda: Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Devries:Junot Therapeutics: Employment. Piasecki:Juno Therapeutics: Employment, Equity Ownership; Cascadian Therapeutics: Patents & Royalties; Amgen: Patents & Royalties. Ziyad:Juno Therapeutics: Employment, Equity Ownership. Blake:Celgene: Employment, Equity Ownership. Byon:Juno Therapeutics: Employment, Equity Ownership. Jakubowiak:Janssen: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Adaptive Biotechnologies: Consultancy, Honoraria; SkylineDx: Consultancy, Honoraria.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2042-2042 ◽  
Author(s):  
Arianne Perez ◽  
Lynn Navale ◽  
John M. Rossi ◽  
Yueh-wei Shen ◽  
Yizhou Jiang ◽  
...  

Abstract This study is supported in part by funding from the CooperativeResearch and Development Agreement (CRADA) between the National Cancer Institute and Kite Pharma Introduction: Chimeric antigen receptor (CAR) engineered autologous T-cell therapy has shown promising efficacy in B-cell malignancies in an ongoing phase 1 study (Kochenderfer et al. J Clin Oncol 2014). Anti-CD19 CAR T-cell product characteristics and potential pharmacodynamic markers from patients in this study were evaluated together with updated clinical responses. Methods: In this National Cancer Institute (NCI) clinical trial (NCT00924326), patients with relapsed/refractory B-cell malignancies received conditioning with cyclophosphamide and fludarabine daily for 3 days starting on day -5; followed by 1-2 x 106/kg anti-CD19 CAR T cells engineered with a CAR expressing CD28 and CD3-zeta signaling domains. Forty one cytokines, chemokines and immune response related markers were measured in the serum of patients prior to conditioning and CAR T-cell infusion, and during an interval of 4 weeks post-CAR T-cell infusion. EMD Millipore Luminex® xMAP® multiplex assays were used to measure all analytes. A Luminex 200™ instrument and xPONENT® 3.1 software were used for data acquisition and analysis. Major T-cell phenotypic markers including CD4, CD8, CD45RA and CCR7 were evaluated by multicolor flow cytometry on CAR-expressing T cells prior to and post-infusion, using a BD FACSCanto II. FlowJo software was used for data analysis. T-cell marker expression, as well as cytokine and chemokine levels were analyzed together with the clinical response to anti-CD19 CAR T cells. Maximum fold increase (MFI) was defined as the maximum fold change of measured analytes above baseline (pre-conditioning, day -5) across sampling timepoints. Results: Anti-CD19 CAR T-cell products, PBMCs from 12 patients, and serum samples from 15 patients have been evaluated. In 12 patient lots evaluated to date, the median CD4+/CD8+ CAR T-cell ratio was 0.48 (range 0.02-6.12). In addition, the median ratio between naïve (TN) plus central memory T cells (TCM), and more differentiated effector memory (TEM) plus effector cells (TE), was 0.48 (range 0.1-16.8). Post-hoc analyses adjusted for multiple comparisons showed that the frequency of CD4+ TN and TCM cells in the 6-8 day T-cell lots was significantly greater than that of CD4+ TN and TCM cells in the 10 day T-cell lots. The corresponding frequencies of CD8+ TN and TCM cells in the 6-8 day T-cell lots compared to 10 day T-cell lots approached significance, but did not meet the threshold after multiplicity adjustment. Clinical responses were seen across broad ranges of CD4+/CD8+ and (TN+TCM)/(TEM+TE) ratios in the CAR T-cell product. CAR T cells upregulated T-cell activation and immune modulating markers, as well as released measurable levels of cytokines and chemokines in response to CAR engagement of CD19 in vitro, or post-infusion. Cytokine and chemokine levels achieved their peak 3-10 days post T-cell infusion and returned to baseline generally within 3 weeks. Key pro-inflammatory cytokines and markers were upregulated: IL-6 median fold increase (MFI) at peak of 66 (interquartile range 5-152), IFN-g MFI 57 (13-126), C-reactive protein MFI 6 (4-42); immune homeostatic cytokines IL-15 MFI 19 (7-54), IL-2 MFI 20 (4-22), IL-10 MFI 10 (4-15); chemokines monocyte chemotactic protein (MCP)-1 MFI 7 (5-9), MCP-4 MFI 4 (2-5); and the immune effector molecules granzyme A MFI 7 (6-17) and granzyme B MFI 5 (3-9). Further analyses are ongoing. Conclusion: Clinical responses were observed irrespective of the CD4+/CD8+ ratio in the CAR T cell product. Cytokines and immune effector mediators peaked and cleared within 3 weeks. This pharmacodynamic profile reveals a rapid and coordinated sequence of T cell activation underlying durable responses in patients with B-cell malignancies. Disclosures Perez: Kite Pharma: Employment, Equity Ownership. Navale:Kite Pharma: Employment, Equity Ownership; Amgen: Equity Ownership. Rossi:Kite Pharma: Employment, Equity Ownership; Amgen: Equity Ownership. Shen:Kite Pharma: Employment, Equity Ownership. Jiang:Kite Pharma: Employment, Equity Ownership. Sherman:Amgen: Equity Ownership; Kite Pharma: Employment, Equity Ownership. Mardiros:Kite Pharma: Employment, Equity Ownership. Yoder:Kite Pharma: Employment, Equity Ownership. Go:Kite Pharma: Employment, Equity Ownership; Amgen: Equity Ownership. Rosenberg:Kite Pharma: Other: CRADA between Surgery Branch-NCI and Kite Pharma. Wiezorek:Kite Pharma: Employment, Equity Ownership, Other: Officer of Kite Pharma. Roberts:Kite Pharma: Employment, Equity Ownership, Other: Officer of Kite Pharma. Chang:Kite Pharma: Employment, Equity Ownership, Other: Officer of Kite Pharma. Bot:Kite Pharma: Employment, Equity Ownership.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4437-4437 ◽  
Author(s):  
Eric R. Lutz ◽  
Srikanta Jana ◽  
Lakshmi Rudraraju ◽  
Elizabeth DeOliveira ◽  
Jing Zhou ◽  
...  

Background The type of T cell used in generating chimeric antigen receptor (CAR) T cells is an important choice. Evidence suggests that T cells that are early in the effector/memory differentiation pathway with more stemness and greater potential to persist are better than more differentiated T cells with less stemness that are more readily exhausted and have less potential to persist. Marrow-infiltrating Lymphocytes (MILsTM) is a novel form of adoptive T cell therapy composed of patient-autologous, polyclonal CD4 and CD8 T cells that are activated and expanded from the bone marrow. Genetically unmodified MILsTM have demonstrated antitumor activity in patients with multiple myeloma and are being developed for several other tumor types, including non-small cell lung cancer and other solid tumors. Distinguishing features of bone marrow T cells used to produce MILsTM include their memory phenotype, inherent tumor antigen-specificity, higher CD8:CD4 ratio and ability to persist long-term when compared to peripheral blood lymphocytes (PBLs) which is the T cell source used to produce currently approved CAR-T therapies. Based on these differences, we hypothesize that MILsTM provide a more robust and better fit platform for CAR-T therapy compared to PBLs. Using a CD38-specific, 4-1BB/CD3z-signaling CAR as an initial model, we have demonstrated the feasibility of producing CAR-modified MILsTM (CAR-MILsTM) and showed that CAR-MILsTM demonstrate superior killing in vitro compared to CAR-T cells generated from patient-matched PBLs (CAR-PBLs). Herein, we build on our previous data and add a second BCMA-specific CAR model. We use the two multiple myeloma model systems to compare cytolytic potential, functionality, and expression of phenotypic markers of memory, stemness and exhaustion between patient-matched CAR-MILsTM and CAR-PBLs. Methods Matched pairs of CAR-MILsTM and CAR-PBLs were produced from the bone marrow and blood of multiple myeloma patients. Two different in vitro cytotoxicity assays, the RTCA xCelligence real-time impedance and FACS assays, were used to evaluate antigen-specific killing of target tumor cells. Functionality of CD4 and CD8 CAR-T cells, at the single-cell level, was evaluated by measuring the secretion of 32 cytokines and chemokines following in vitro antigen-specific stimulation using IsoPlexis IsoCode chips and analyzed using IsoPeak. Expression of markers of T cell memory (CD45RO & CCR7/CD62L), stemness (CD27) and exhaustion (PD1 & TIM3) on CAR-MILsTM and CAR-PBLs prior to and following antigen-specific stimulation was evaluated by flow-cytometry (FACS). Results CAR-MILsTM demonstrated superior killing of tumor target cells in vitro, regardless of the antigen specificity of the CAR, when compared to matched CAR-PBLs and this superiority persisted even upon repeated antigen encounter - a factor that may be critical in guaranteeing better anti-tumor efficacy and persistence. CAR-MILsTM demonstrated increased polyfunctionality (secretion of 2+ cytokines per cell) and an increased polyfunctional strength index (PSI) following antigen-stimulation compared to CAR-PBL in both CD4 and CD8 T cells. The enhanced PSI in CAR-MILsTM was predominately mediated by effector, stimulatory and chemoattractive proteins associated with antitumor activity including Granzyme B, IFNg, IL-8, MIP1a and MIP1b. Coincidentally, increased PSI and enhanced secretion of these same proteins was reported to be associated with improved clinical responses in patients with Non-Hodgkin lymphoma treated with CD19-specific CAR-T therapy. Expression of memory markers on CD4 and CD8 T cells were similar in CAR-MILsTM and CAR-PBLs both prior to and following antigen-stimulation. Although expression of CD27, PD1 and TIM3 were similar at baseline, CAR-MILs maintained higher levels of CD27 and lower levels of PD1 and TIM3 compared to CAR-PBLs following antigen-stimulation in both CD4 and CD8 T cells. Conclusions Collectively, our data suggest that CAR-MILsTM have several advantages over CAR-PBLs, including increased cytolytic potential, enhanced polyfunctionality, increased stemness and less exhaustion. Based on these differences and the inherent antitumor properties of MILsTM, we speculate that CAR-MILsTM would be more potent and effective than currently approved CAR-T products derived from PBLs. Disclosures Lutz: WindMIL Therapeutics: Employment, Equity Ownership. Jana:WindMIL Therapeutics: Employment, Equity Ownership. Rudraraju:WindMIL Therapeutics: Employment, Equity Ownership. DeOliveira:WindMIL Therapeutics: Employment, Equity Ownership. Zhou:Isoplexis: Employment, Equity Ownership. Mackay:Isoplexis: Employment, Equity Ownership. Borrello:Aduro: Patents & Royalties: intellectual property on allogeneic MM GVAX; BMS: Consultancy; WindMIL Therapeutics: Equity Ownership, Patents & Royalties, Research Funding; Celgene: Honoraria, Research Funding, Speakers Bureau. Noonan:WindMIL Therapeutics: Employment, Equity Ownership, Patents & Royalties; Aduro: Patents & Royalties: intellectual property on allogeneic MM GVAX.


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