ALBERT

Description: Introduction: Continuous treatment with lenalidomide (len) is a new standard of care in frontline multiple myeloma (MM) (Facon. Blood. 2018;131:301-310; Pulte. Oncologist. 2018;23:734-739). The increased adoption of continuous len treatment and len maintenance highlights the need for active regimens for the treatment of MM that has relapsed or become refractory to len. Once-weekly carfilzomib (K) at 70 mg/m2 (Berenson. Blood. 2016;127:3360-3368; Moreau. Lancet Oncol. 2018;19:953-964) and twice-weekly K at 56 mg/m2 (Dimopoulos. Lancet Oncol. 2016;17:27-38) in combination with low-dose dexamethasone (d) have shown a favorable benefit-risk profile for the treatment of relapsed and/or refractory MM. This post-hoc analysis will assess the efficacy and safety of Kd in len exposed and refractory MM. Methods: Individual patient data from the phase 1/2 CHAMPION-1 (CH-1), phase 3 ENDEAVOR, and phase 3 ARROW studies were pooled to evaluate progression-free survival (PFS), overall response rate (ORR), and safety for those with previous exposure or refractoriness to len treatment. The once-weekly Kd dosing schedule in CH-1 (Berenson. Blood. 2016;127:3360-3368) and ARROW (Moreau. Lancet Oncol. 2018;19:953-964) and the twice-weekly Kd dosing schedule in ENDEAVOR (Dimopoulos. Lancet Oncol. 2016;17:27-38) have been previously described. Patients who received once-weekly Kd at 70 mg/m2 in CH-1 and ARROW, and patients who received twice-weekly Kd at 56 mg/m2 from ENDEAVOR were included in the analysis. Patients were assigned to a group according to prior lines of therapy and previous len exposure: (1) combined CH-1 and ENDEAVOR patient population (N=39) that had received 1 prior line of therapy and was previously exposed but not refractory to len (Kd, 1 prior len exposed); (2) combined CH-1 and ENDEAVOR patient population (N=32) that had received 1 prior line of therapy and was refractory to len in the last line of therapy (Kd, 1 prior len refractory); (3) combined CH-1, ENDEAVOR, and ARROW patient population (N=65) that had received 2 to 3 prior lines of therapy and was exposed but not refractory to len (Kd, 〉1 prior len exposed); (4) combined CH-1, ENDEAVOR, and ARROW patient population (N=304) that had received 2 to 3 prior lines of therapy and was refractory to len in any line of previous therapy (Kd, 〉1 prior len refractory). Results: PFS, ORR, and safety outcomes in the pooled len exposed and refractory patient populations are shown (Table 1). Len-exposed patients treated with Kd in first relapse had a median PFS of 18.3 months (95% confidence interval [CI] 14.1-21.0); PFS rate at 18 months was 54.0%. When len-refractory patients were treated with Kd in first relapse, median PFS was 15.6 months (95% CI 9.6-not estimable [NE]) and the PFS rate at 18 months was 43.1%. For len-exposed patients treated in second or third relapse, the median PFS for Kd was not reached (95% CI 10.3-NE) and PFS rate at 18 months was 57.1%. For len-refractory patients treated with Kd in second or third relapse, median PFS was 8.8 months (95% CI 7.5-11.2) and the PFS rate at 18 months was 27.8%. ORR was approximately 90% (Kd, 1 prior len exposed), 81% (Kd, 1 prior len refractory group), 77% (Kd, 〉1 prior len exposed), and 61% (Kd, 〉1 prior len refractory). Median K treatment duration (range) was 56.0 (4.0-213.0) months (Kd, 1 prior len exposed), 36.6 (1.0-201.1) months (Kd, 1 prior len refractory), 36.1 (1.1-210.7) months (Kd, 〉1 prior len exposed), and 34.0 (0.1-198.0) months (Kd, 〉1 prior len refractory). The incidence of treatment-emergent grade ≥3 adverse events (AEs) was 84.6% for patients in the Kd, 1 prior len-exposed group, 81.3% for patients in the Kd, 1 prior len-refractory group, 76.9% for patients in the Kd, 〉1 prior len-exposed group, and 74.8% for patients in the Kd, 〉1 prior len-refractory group. The rate of serious AEs in each of the pooled patient groups in this analysis is presented (Table 1). Conclusion: The Kd doublet is effective and safe in MM patients relapsing on or after treatment with len, and for patients who are refractory to len. Although data are limited by small sample size, the median PFS of 15.6 months for Kd in len-refractory patients treated in first relapse is similar in magnitude to the median PFS reported for novel triplet therapy in this population. Disclosures Mateos: Abbvie: Consultancy, 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; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, 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. Berdeja:Genentech: Research Funding; Bluebird: Research Funding; Bristol-Myers Squibb: Research Funding; Takeda: Research Funding; Janssen: Research Funding; Amgen: Research Funding; Celgene: Research Funding; Glenmark: Research Funding; Novartis: Research Funding; Teva: Research Funding; Sanofi: Research Funding; Poseida Therapeutics, Inc.: Research Funding. Dimopoulos:Amgen: Honoraria; Bristol-Myers Squibb: Honoraria; Takeda: Honoraria; Celgene: Honoraria; Janssen: Honoraria. Siegel:Takeda: Consultancy, Honoraria, Speakers Bureau; Karyopharm: Consultancy, Honoraria; Merck: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau. Ho:Novartis: Honoraria; Janssen: Honoraria; Amgen: Honoraria; Takeda: Honoraria, Other: travel to meeting; Celgene: Other: travel to meeting. Huang:Amgen: Employment, Equity Ownership. Sersch:Amgen: Employment. Zahlten-Kumeli:Amgen: Employment, Equity Ownership. Kimball:Amgen: Employment, Equity Ownership; WindMIL Therapeutics: Equity Ownership. Weisel:Amgen, BMS, Celgene, Janssen, and Takeda: Honoraria; Amgen, BMS, Celgene, Janssen, Juno, Sanofi, and Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen, Celgene, Janssen, and Sanofi: Research Funding.

Description: Background: Chimeric antigen receptor T-cells (CAR-T) targeting CD19 have shown clinical efficacy in high-risk B-cell lymphomas, which has led to approval of 2 such therapies (axicabtagene ciloleucel and tisagenlecleucel) for large B-cell lymphoma after 2 lines of treatment. Despite the promising results, complete remission (CR) is achieved in ~ 50% of patients, and with longer follow-up progression-free survival is around 40%. Therefore, finding effective treatments for high-risk B-NHLs remains an unmet need. CD20 is a proven therapeutic target for B-Cell Non-Hodgkin Lymphomas (B-NHL), supported by previously approved naked and radiolabeled anti-CD20 monoclonal antibodies and a number of studies investigating novel bispecific antibodies targeting this antigen. CD20-targeted CAR-T is another potential adoptive immunotherapy option that could be utilized in combination or sequentially before or after CD19 CAR-T, depending on efficacy. Here, we present our ongoing phase I/II clinical trial investigating safety and efficacy of CD20 CAR-T for high-risk B-NHLs (NCT03277729). Methods: MB-106 is a fully human third-generation CD20 targeted CAR-T with both 4-1BB and CD28 costimulatory domains. In the phase I portion of the study we use a continual reassessment method dose escalation design to find the maximally tolerated dose. Lymphodepletion (LD) chemotherapy consists of fludarabine and cyclophosphamide. Patients (pts) will undergo a mandatory biopsy before LD to confirm the diagnosis and CD20 expression. A repeat research biopsy will be done between 10-16 days after CAR-T infusion (Figure 1). Except for the first patient of each dose cohort, treatment is given in the outpatient setting (Fred Hutch/Seattle Cancer Care Alliance) and pts will only be admitted to the University of Washington Medical Center if clinically indicated after CAR-T infusion. Response to treatment will be assessed on day 28 using Lugano criteria. Patients with relapsed or refractory CD20 positive B-NHL are eligible, including but not limited to DLBCL, primary mediastinal lymphoma, follicular lymphoma or other indolent histologies, and mantle cell lymphoma. Prior treatment with CD19 CAR-T is permitted as long as there is evidence of B-cell recovery in peripheral blood (≥ 20 B cells/µl) as a functional test to rule out persistent CD19 CAR-Ts. Patients need to meet standard organ function criteria and have adequate blood counts (ANC 〉750, Hb 〉8.5, Plts 〉50,000). Patients with significant neurologic conditions, active CNS lymphoma, or need for systemic immunosuppressive therapy are excluded from the study. Disclosures Shadman: Mustang Bio: Research Funding; Verastem: Consultancy; Genentech: Consultancy, Research Funding; Atara Biotherapeutics: Consultancy; Pharmacyclics: Consultancy, Research Funding; ADC Therapeutics: Consultancy; Celgene: Research Funding; Sound Biologics: Consultancy; TG Therapeutic: Research Funding; Acerta Pharma: Research Funding; Sunesis: Research Funding; Gilead: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; BeiGene: Research Funding; Astra Zeneca: Consultancy. Gopal:Seattle Genetics, Pfizer, Janssen, Gilead, Sanofi, Spectrum, Amgen, Aptevo, BRIM bio, Acerta, I-Mab-pharma, Takeda, Compliment, Asana Bio, and Incyte: Honoraria; Seattle Genetics, Pfizer, Janssen, Gilead, Sanofi, Spectrum, Amgen, Aptevo, BRIM bio, Acerta, I-Mab-pharma, Takeda, Compliment, Asana Bio, and Incyte.: Consultancy; Teva, Bristol-Myers Squibb, Merck, Takeda, Seattle Genetics, Pfizer, Janssen, Takeda, and Effector: Research Funding. Smith:Pharmacyclics: Research Funding; Genentech: Research Funding; Ignyta (spouse): Research Funding; Portola Pharmaceuticals: Research Funding; Bristol-Myers Squibb (spouse): Research Funding; Ayala (spouse): Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma BV: Research Funding; Merck Sharp & Dohme Corp: Consultancy, Research Funding; Incyte Corporation: Research Funding; Seattle Genetics: Research Funding; Denovo Biopharma: Research Funding. Lynch:Juno Therapeutics: Research Funding; Rhizen Pharmaceuticals S.A: Research Funding; Takeda Pharmaceuticals: Research Funding; Johnson Graffe Keay Moniz & Wick LLP: Consultancy; Incyte Corporation: Research Funding; T.G. Therapeutics: Research Funding. Ujjani:Pharmacyclics: Honoraria; PCYC: Research Funding; Gilead: Consultancy; Astrazeneca: Consultancy; Atara: Consultancy; Genentech: Honoraria; AbbVie: Honoraria, Research Funding. Turtle:T-CURX: Membership on an entity's Board of Directors or advisory committees; Humanigen: Other: Ad hoc advisory board member; Eureka Therapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Precision Biosciences: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Caribou Biosciences: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Allogene: Other: Ad hoc advisory board member; Juno Therapeutics: Patents & Royalties: Co-inventor with staff from Juno Therapeutics; pending, Research Funding; Nektar Therapeutics: Other: Ad hoc advisory board member, Research Funding; Kite/Gilead: Other: Ad hoc advisory board member; Novartis: Other: Ad hoc advisory board member. Yeung:Pfizer: Research Funding; OBI Pharmaceutical: Research Funding; Merck: Consultancy; DiaCarta: Consultancy. Sersch:Mustang Bio: Employment. Maloney:Juno Therapeutics: Honoraria, Patents & Royalties: patients pending , Research Funding; Celgene,Kite Pharma: Honoraria, Research Funding; BioLine RX, Gilead,Genentech,Novartis: Honoraria; A2 Biotherapeutics: Honoraria, Other: Stock options . Till:Mustang Bio: Patents & Royalties, Research Funding.

Description: Introduction Multiple issues arise for a wider application of chimeric antigen receptor (CAR) T cell therapy including manufacturing time and antigen escape. Here we report data on an anti-CD19/CD22 dual CAR-T (GC022F) therapy based on a novel manufacturing platform, from a phase I clinical study (NCT04129099) in treating patients with B-cell acute lymphoblastic leukemia (B-ALL). Methods Peripheral blood (PB) mononuclear cells were obtained by leukapheresis. T-cells were separated and transduced with lentivirus that encodes a CD19/CD22 directed 4-1BB: ζ CAR. GC022F cells were manufactured using a novel FasTCARTM platform which takes 24 hours, while the conventional CD19/CD22 dual CAR-T (GC022C) cells used as parallel control in the preclinical study were manufactured by conventional process which typically takes 9-14 days. The phase I dose escalation study was initiated to explore the safety and efficacy of GC022F in patients with B-ALL. All patients received a conditioning regimen of IV fludarabine (25mg/m2/d) and cyclophosphamide (250mg/m2/d) for 3 days prior to GC022F infusion. Results When compared with the GC022C, GC022F cells showed 1) less exhaustion as indicated by lower percentage of PD-1+LAG3+ cells following co-culturing with tumor cells, 2) younger phenotypes as demonstrated by more abundant T central memory cells (Tcm; CCR7+CD45RA+ or CD45RO+CD62L+), 3) higher expansion fold at in vitro culture, and 4) high anti-leukemia efficacy in mice model (Fig.1). Comparing in vivo efficacy of GC022F with GC022C cells at lower doses, GC022F treatment were more potent and could reduce tumor burden earlier and faster, and led to significantly prolonged overall survival of the experimental animals. From Nov. 2019 to Jun. 2020, 9 children and 1 adult with B-ALL were enrolled and infused with GC022F, 2 in low-dose (6.0×104/kg), 7 in medium dose (1.0-1.5×105/kg), 1 in high-dose (2.25×105/kg). Patients' median observation time was 99 (14-210) days on the day of cut-off. Characteristics of enrolled patients are shown in Table 1. The median age was 10 (3-48) years, and the median bone marrow (BM) blasts were 21.0 (0.1-63.5) % at enrollment. Three patients had prior CD19 CAR-T cell therapy history and one of whom had prior allogeneic hematopoietic stem cell transplantation (allo-HSCT). After infusion, the median peak of circulating CAR-T cell copy number was 2.29 ×105 copies/µg genomic DNA (0.0014-5.66), which occurred around day 14 (day10 - day 28). Importantly, GC022F persisted well in PB with a median of 2.40×105 copies/µg genomic DNA (0.75-3.98) on day 28 in 5 of 9 patients with available 4 weeks of cellular kinetics data. GC022F exerted a superior safety profile with no observed grade ≥ 3 cytokine release syndrome (CRS) and neurotoxicity in all patients. Among those 6 patients with CRS, only 1 at high dose level had grade 2 CRS; only 1 developed grade 1 neurotoxicity. After GC022F infusion, 6/6 patients with BM blasts 〉 5% at enrollment achieved complete remission (CR) by day 28, 5/6 with minimal residual disease (MRD)-negative CR. For those 4 patients with MRD positive disease at enrollment, 3 became MRD-negative CR by day 28, 1 had persist MRD positive disease and withdrew from the study by 2 weeks. Five of 8 MRD-negative CR patients subsequently made a choice to pursue consolidation allo-HSCT with a median time interval of 57 (48-71) days post GC022F infusion and all have remained in MRD-negative CR except 1 died from graft-versus-host disease (GVHD) and infection 143 days post GC022F infusion. Of the other 3 patients without allo-HSCT, 2 relapsed with CD19+/CD22+ disease at 12-16 weeks follow-up, including the patient with prior history of CD19 CAR-T treatment and transplant. Conclusion This study demonstrated that anti-CD19/CD22 dual CAR T-cells could be successfully manufactured by FasTCARTM technology in 24 hours, with younger and less exhausted phenotypes. Moreover, the Dual FasTCAR-T cells showed more potent efficacy in xenograft mouse model compared to the conventional dual CAR-T cells. Our clinical data demonstrate that GC022F is safe and efficacious in treating patients with CD19+CD22+ B-ALL. More data on additional patients and longer observation time are needed to further evaluate CD19/CD22 dual FasTCAR-T cell product. Disclosures Cai: Gracell Biotechnologies Ltd: Current Employment. Wang:Gracell Biotechnologies Ltd: Current Employment. Chen:Gracell Biotechnologies Ltd: Current Employment. Ye:Gracell Biotechnologies Co., Ltd.: Current Employment. He:Gracell Biotechnologies Co., Ltd.: Current Employment. Cao:Gracell Biotechnologies Ltd: Current Employment. Sersch:Gracell Biotechnologies Co., Ltd.: Current Employment.

Description: Introduction To further improve efficacy and duration of response of CAR-T therapy for Relapsed/Refractory Multiple Myeloma (R/R MM), we have designed a dual FasT CAR-T targeting both B cell maturation antigen (BCMA), a well-established MM target, and CD19, which is expressed on MM cells and their progenitors. Here we report early results from the first-in-human multicenter clinical study (NCT04236011; NCT04182581) to determine safety, pharmacokinetics (PK) and efficacy of BCMA-CD19-directed FasT CAR-T (GC012F) in patients with R/R MM. Methods The BCMA-CD19 dual CAR was constructed by linking BCMA and CD19 scFv, joined by a CD8 hinge, transmembrane domain, co-stimulatory domain and CD3z. Peripheral blood (PB) mononuclear cells were obtained by leukapheresis, T cells were isolated and CAR-T cells were manufactured (FasT CAR platform). From September 2019 to April 2020, we enrolled 16 heavily pretreated R/R MM patients (Age range 27-71), with a median of 5 prior lines of therapies (range 2-7), 93.8% (15/16) of these patients were high risk as defined by mSMART criteria, 5 had extramedullary disease. 4 out of 16 patients had received prior anti CD38 therapy, 93.8% (15/16) patients had received prior IMiD, all patients received at least 1 prior PI and corticosteroids with 3 patients being primary refractory to last therapy. Prior to CAR-T infusion patients received a conditioning regimen over 3 days of 30 mg/m2/d fludarabine and 300 mg/m2/d cyclophosphamide. CAR-T cells were administered in a single infusion at 3 dose levels 1x105/Kg (DL1) (1 patients), 2x105/Kg (DL2) (9 patients) and 3x105/Kg (DL3) (6 patients). Results As of July 17th 2020, all 16 patients were evaluable for response assessment, 15 out of 16 patients responded to treatment (ORR 93.8%) in all dose levels with the earliest response observed at day 28. Best response to date is MRD- CR/sCR in 9/16 patients (56.3%). In DL3 100% (6/6) of patients achieved sCR, 3 at data cut off had been confirmed by PET-CT. In all response evaluable patients, 78.6% (11/14) were MRD- by flow at month 1, and 100% at month 3 (11/11) and 6 (10/10) (sensitivity by flow cytometry measured at 10-4 in 7 patients, and at 10-6 in 9 patients tested by EuroFlow with at least 1.08x107 cells analyzed). At data cut off, the median follow up time was 7.3 months, the longest follow up was 10 months post infusion. CAR-T PK in PB was monitored by qPCR and flow cytometry. The CAR-T median proliferation peak was reached on Day10 (Day8-Day14), and the median peak copy number was 140,982 (16,011-374,346) copies /ug DNA. GC012F showed an acceptable safety profile with 14 out of 16 patients experiencing a cytokine release syndrome (CRS) grade 1-2 (n=14, 87.5%) and 2 grade 3 (n=2, 12.5%). The median duration of CRS was 4 days (1-8 days). No neurotoxicity of any grade was observed. One patient (DL2) presented with fever and died shortly after Day 78 of unknown cause during the COVID-19 Pandemic. Two patients had progression of extramedullary disease while achieving MRD negativity at month 1 and 3, respectively. At landmark analysis at 6 months, all patients in DL3 had achieved and maintained MRD- sCR including patients heavily pretreated including Daratumumab - among them 83.3% (5/6) patients in DL3 had high risk features according to mSMART criteria, and 5 out of 6 patients in DL3 were assessed by 10-6 Euroflow for MRD. The study is still enrolling patients and we will continue to be monitoring safety and efficacy including duration of response. Conclusion The data of BCMA-CD19 dual FasT CAR-T showed an early and high response rate with 93.8% ORR to date with a promising early high MRD-sCR rate in the highest dose level DL3 (100%) which was sustained with a median duration of follow up of 7.3 months at cut off. The data shows very promising activity of the BCMA-CD19 dual FasT CAR-T with a favorable safety profile in R/R MM patients. 93.8% (15/16) of the treated patients exhibited high risk features - a specifically difficult to treat patient population which remains a high unmet medical need in Multiple Myeloma. This data indicates that BCMA-CD19 dual FasT CAR-T (GC012F) may present an effective new treatment option for patients with R/R MM including those with high-risk features who failed multiple prior therapies including anti-CD38. The study is still ongoing and enrolling patients, we will update the results as they become available. Disclosures Zhao: Gracell Biotechnologies Ltd: Current Employment. Han:Gracell Biotechnologies Co., Ltd.: Current Employment. Chen:Gracell Biotechnologies Ltd: Current Employment. Xu:Gracell Biotechnologies Ltd: Current Employment. Zhang:Gracell Biotechnologies Ltd: Current Employment. He:Gracell Biotechnologies Co., Ltd.: Current Employment. Shi:Gracell Biotechnologies Ltd: Current Employment. Han:Gracell Biotechnologies Co., Ltd.: Current Employment. Ye:Gracell Biotechnologies Co., Ltd.: Current Employment. Wang:Gracell Biotechnologies Ltd: Current Employment. Liu:Gracell Biotechnologies Co., Ltd.: Current Employment. Shen:Gracell Biotechnologies Ltd: Current Employment. Cao:Gracell Biotechnologies Ltd: Current Employment. Sersch:Gracell Biotechnologies Co., Ltd.: Current Employment.