scholarly journals Efficacy and Safety Results of a Phase 1 Study of 177 lu-DOTA-HH1 (Betalutin®) with and without HH1 Pre-Dosing for Patients with Relapsed CD37+ Non-Hodgkin B Cell Lymphoma (NHL)

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 5118-5118
Author(s):  
Arne Kolstad ◽  
Ulf Madsbu ◽  
Bjørg Bolstad ◽  
Caroline Stokke ◽  
Tore Bach-Gansmo ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Board Of Directors ◽  
Cell Lymphoma ◽  
Safety Data ◽  
Efficacy And Safety ◽  
B Cell Malignancies ◽  
Advisory Committees ◽  
Mantle Cell ◽  
Equity Ownership

Abstract Background: CD37 is an internalizing transmembrane antigen highly expressed by normal B cells and on most of B-cell malignancies, and represents an interesting therapeutic target for the treatment of B-cell NHL. 177Lu-DOTA-HH1 (Betalutin®) is a novel CD37-targeting antibody radionuclide conjugate in clinical development. It consists of a CD37-binding murine IgG1 antibody HH1 labelled with the short-ranged beta-emitter lutetium-177 (T½ = 6.7 days) chelated to DOTA. 177Lu-DOTA-HH1 is delivered in a ready-to-use formulation. Efficacy and safety data of patients (pts) receiving 177Lu-DOTA-HH1 with HH1 pre-dosing, as well as new efficacy and safety data from pts receiving 177Lu-DOTA-HH1 without HH1 pre-dosing will be presented. Methods: Pts with relapsed incurable CD37 positive NHL of follicular grade I-IIIA, marginal zone, mantle cell, lymphoplasmacytic and small lymphocytic subtypes and with platelet counts ≥ 150 x109/l were eligible for inclusion in the study. In a 3+3 study design pts received rituximab (375 mg/m2) day 1 and 8 in order to deplete normal B cells. On day 29 pre-dosing with HH1 (50 mg, cold CD37 antibody) was administered before 177Lu-DOTA-HH1 injection (Arm 1). In Arm 2 177Lu-DOTA-HH1 was administered without HH1 pre-dosing on day 29. The starting doses for Arm 1 and 2 were 10 MBq/kg b.w. and 15 MBq/kg b.w, respectively. Pts enrolment has been completed (n=13) in Arm 1 with the dose-limiting toxicity (DLT) observed at 20 MBq/kg bw and a dose expansion cohort is currently open for enrollment at 15 MBq/kg with HH1 pre-dosing. Arm 2 is currently open for enrollment. Tumour response was assessed by FDG PET/CT scans (Cheson 2007), and pts will be followed for 5 years. Results: Arm 1:A total of13 (M/F 11/2) pts, median age 68 years, follicular lymphoma (n=12), and mantle cell lymphoma (n=1) have been enrolled since the study start in December 2012. The range of prior therapies was 1 to 8, where 5 of 13 pts were refractory to rituximab. The most common toxicities observed were hematologic and all DLTs were reversible and manageable. At 20 MBq/kg (n=3) G 3/4 neutropenia and/or thrombocytopenia were observed in all pts and platelet transfusions were required in 2 pts. At 15 MBq/kg (n=6) DLTs were: 1 G 3 thrombocytopenia lasting >14 days and 1 G 4 neutropenia/ thrombocytopenia lasting >7 days. The median time to nadir for platelets and neutrophils was 40 and 49 days, respectively. No pts experienced febrile neutropenia. Serious AEs were reported in 5 pts: at 10 MBq/kg pneumonia (possibly related) and pulmonary embolism (PE) unrelated, in the same pt, with history of PE; thrombocytopenia requiring platelet transfusions (2 pts) and epistaxis in 1 of them (20 MBq/kg), possibly related; transient atrial fibrillation (2 pts) at 15 MBq/kg, possibly related. No secondary malignancies or other long term events have been observed. Best overall tumor response observed across all dose levels were 4 complete and 3 partial remissions, 2 stable disease and 4 progression of disease (one pt had confirmed transformed lymphoma at 3 months). The duration of response (complete and partial remissions) ranged from 6 to more than 21 months. One patient is still in remission after 2 years. The median response duration has not yet been reached. Arm 2: Inclusion in this arm is ongoing. Data on efficacy and safety will be presented and compared with the pts receiving pre-dosing. Conclusions: 177Lu-DOTA-HH1, which is a single dose ready-to-use formulation, has a predictable and manageable safety profile. Most AEs were hematological in nature, all transient and reversible. Promising efficacy and durable responses have been observed. 177Lu-DOTA-HH1 has the potential to be a novel therapy for B-cell malignancies. Disclosures Kolstad: Nordic Nanovector ASA: Membership on an entity's Board of Directors or advisory committees, Research Funding. Bolstad:Nordic Nanovector ASA: Employment. Bruland:Nordic Nanovector ASA: Equity Ownership. Dahle:Nordic Nanovector ASA: Employment, Equity Ownership. Hartvig Larsen:Nordic Nanovector ASA: Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

Phase 1b/2a Open-Label, Multiple-Dose, Dose-Escalation Study To Evaluate The Safety and Tolerability Of Intravenous Infusion Of SNS01-T In Patients With Relapsed Or Refractory Multiple Myeloma, Mantle Cell Lymphoma, Or Diffuse Large B Cell Lymphoma

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1950-1950 ◽  
Author(s):  
John A Lust ◽  
Charles Barranco ◽  
Saad Z Usmani ◽  
Frits van Rhee ◽  
Mehdi Hamadani ◽  
...  
Keyword(s):  
B Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Advisory Committees ◽  
Large B Cell Lymphoma ◽  
Mantle Cell ◽  
Equity Ownership ◽  
Pro Inflammatory Cytokines

Abstract Eukaryotic translation initiation factor 5A (eIF5A) has been implicated in the regulation of cell proliferation, apoptosis, and inflammation, and is the only known protein to be modified by hypusination. Hypusinated eIF5A, the predominant form of eIF5A in cancer cells, is involved in cell survival and activation of inflammatory pathways. In contrast, accumulation of the unhypusinated form of eIF5A is associated with apoptosis and mutants of eIF5A that cannot be hypusinated (e.g. eIF5AK50R) are pro-apoptotic. SNS01-T was designed to treat B-cell cancers and consists of two active components: a plasmid DNA expressing the pro-apoptotic eIF5AK50R under the control of a B cell-specific promoter, and an siRNA against an untranslated region of native eIF5A mRNA. When these two components are combined with linear polyethyleneimine (PEI), the nucleic acids are condensed into nanoparticles for protection from degradation in the blood and enhanced cellular delivery. The mode of action of SNS01-T is siRNA-mediated inhibition of hypusinated eIF5A and simultaneous over-expression of pro-apoptotic eIF5AK50R to induce cell death. In vitro cell studies and in vivo xenograft studies have demonstrated the efficacy of this approach. The safety and tolerability of intravenous administration of SNS01-T is being investigated in a first-in-human Phase1b/2a study in patients with relapsed or refractory multiple myeloma (MM), mantle cell lymphoma (MCL) or diffuse large B cell lymphoma (DLBCL). Eligible patients are being enrolled sequentially into four cohorts at increasing doses. Each patient receives an intravenous infusion of SNS01-T twice weekly for 6 consecutive weeks. Eligible patients must have been diagnosed with MM according to IMWG criteria, or with MCL or DLBCL with histologic confirmation. Patients also must have measurable disease, have relapsed or refractory disease after two or more prior treatment regimens, have a life expectancy of at least 3 months, and not be eligible to receive any other standard therapy known to extend life expectancy. The primary objective is to evaluate the safety and tolerability of multiple escalating doses of SNS01-T. Secondary objectives include analysis of pharmacokinetics, immunogenicity, pro-inflammatory cytokines, and therapeutic efficacy. The required 3 patients per cohort have completed the dosing schedule in cohorts 1 and 2 from a total of 10 patients enrolled (9 patients with MM and 1 with DLBCL). Of the ten patients enrolled, four completed the full treatment period, two did not complete dosing but were evaluable for safety, and four (three in cohort 1 and one in cohort 2) discontinued treatment after fewer than 8 doses and were not evaluable. There were no drug-related serious adverse events or dose limiting toxicities in either cohort 1 or 2. In cohort 1 (0.0125 mg/kg SNS01-T), two of three evaluable patients did not progress on treatment and were considered stable at week 3 and week 6, the end of the dosing regimen. The third patient progressed after receiving 10 of the 12 doses and was evaluable for safety. In cohort 2 (0.05 mg/kg), 3 patients (2 with MM and 1 with DLBCL) were evaluable for safety. Stabilization of serum monoclonal protein levels was observed in one MM patient of cohort 2. Two patients (1 with MM and 1 with DLBCL) progressed after receiving 8 of the 12 doses and were evaluable for safety. Results from ongoing pharmacokinetic studies, immunogenicity studies, and quantification of pro-inflammatory cytokines will be discussed. The planned dose levels for the third and fourth groups are 0.2 and 0.375 mg/kg, respectively. The results to date of this first-in-human clinical trial indicate that SNS01-T can be administered safely and the MTD has not yet been reached (Clinical Trials.gov Identifier: NCT01435720). Disclosures: Barranco: Senesco Technologies: Consultancy. Usmani:Celgene, Onyx, Millenium: Consultancy, Research Funding, Speakers Bureau. van Rhee:Jansen&Jansen: Research Funding. Thompson:Senesco Technologies: Consultancy, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees, Research Funding. Taylor:Senesco Technologies: stock options Other. Dondero:Senesco Technologies: Employment. Browne:Senesco Technologies Inc.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees. Siegel:Celgene, Millenium, Onyx (same for all): Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau.

Germinal Center-Derived Lymphomas and Plasmacytomas in Mice with Targeted Deletion of MiR-15a/16-1 in Activated B Cells

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 743-743
Author(s):  
Tomasz Sewastianik ◽  
Jianjun Zhao ◽  
Meng Jiang ◽  
Jianli Wang ◽  
Vinodh Pillai ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Board Of Directors ◽  
Plasma Cells ◽  
Cell Development ◽  
B Cell Development ◽  
B Cell Malignancies ◽  
Advisory Committees ◽  
Equity Ownership ◽  
Activated B Cells

Abstract MicroRNA (miR)-mediated gene regulation plays critical roles in B-cell development and dysregulated expression of miRs has been implicated in the pathogenesis of various types of B-cell malignancies. Somatic deletions of chromosome 13q14, harboring miR-15a/16-1, occurs frequently in B-cell lymphomas suggesting that members of this miR family are tumor suppressors. Consistently, mice with CD19-Cre-induced deletion of miR-15a/16-1 in early B-cells and follicular B-cells develop chronic lymphocytic leukemia (CLL). Since the 13q14 deletion is observed in a broader range of B-cell malignancies, we hypothesized that the type of B-cell malignancy resulting from miR-15a/16-1 down-regulation may depend on the stage of B-cell development at which this deletion occurs. Therefore, we generated a transgenic mouse model in which conditional deletion of miR-15a/16-1 takes place at later stages of B-cell development. To delete miR-15a/16-1 in activated B-cells, miR-15a/16-1fl/fl mice were mated with AID-Cre+/+ mice to obtain AID-Cre+/-; miR-15a/16-1fl/fl compound mice that expressed Cre recombinase from the Activation-induced Cytidine Deaminase (AID promoter) gene - a gene needed for generation of somatic hypermutations in the immunoglobulin (Ig) variable region (V) genes that is highly expressed in activated B-cells and is a well-known marker for germinal center (GC) B-cells. Expression levels of both miR-15a and miR-16-1, but not miR-15b were decreased in GC B-cells of AID-Cre+/-; miR-15a/16-1fl/fl mice as compared with control AID-Cre+/- mice when evaluated by In Situ Hybridization (ISH) analysis. Given that in humans miR-15a, b and 16 are also expressed in GC B-cells, these results demonstrate the validity of this mouse model in which the biological consequences of miR-15a/16-1 deletion can be studied. Next we assessed whether miR-15a/16-1 deletion could affect proliferation and/or survival of GC B-cells. GCs in the spleens of AID-Cre+/-; miR-15a/16-1fl/fl mice at 10 weeks of age were significantly increased in both number and size, and contained a larger number of Ki-67-positive B-cells as compared with spleens of AID-Cre+/- mice. No significant differences in the number of apoptotic cells, neither in the expression of the miR-15a/16-1 putative target BCL2 were detected, indicating that miR-15a/16-1 may play important roles in the proliferation, but not survival of GC B-cells. Apart from mild splenic enlargement and increased number and size of GCs, AID-Cre+/-, miR-15a/16-1fl/fl mice where indistinguishable from AID-Cre+/- mice between 8 and 40 weeks of age as assessed by weight and posture. However, after 48 weeks of age and at variable times thereafter, 80% (32/40) of AID-Cre+/-, miR-15a/16-1fl/fl mice but none from control cohorts (0/30) showed signs of disease. Gross pathologic examination of euthanized AID-Cre+/-; miR-15a/16-1fl/fl mice revealed enlargement of the spleen and lymph nodes. Detailed histological examination revealed in most instances an effacement of normal tissue architecture by a nodular or diffuse population of atypical lymphoid cells, or less commonly by sheets of plasma cells in interfollicular areas. Two distinct patterns of B220+BCL6+BCL2- B-cell lymphomas were identified after detailed analysis. The most common (47%) resembled human follicular lymphoma (FL) and the next in frequency (28%) resembled human diffuse large B-cell lymphoma (DLBCL). The other group of tumors (25%) resembled human plasmacytoma (PC). All three tumor subtypes were clonal, hypermutated and associated with different degrees of preservation of the dendritic meshwork in the lymph nodes. The comparison of lymphomas arising in AID-Cre+/-; miR-15a/16-1fl/fl mice and CD19-Cre+/-; miR-15a/16-1fl/fl mice corroborated that deletion of miR-15a/16-1 at different stages of B-cell development leads to distinct subtypes of B-cell malignancies. Finally, we investigated miR-15a/16-1 expression in human FL and PC and showed that miR-15a/16-1 abundance is significantly decreased in those malignancies when compared with nodal B-cells in reactive GCs and normal plasma cells in interfollicular areas respectively, suggesting that miR-15a/16-1 may play important roles in normal GC B-cell development as well as in the pathogenesis of FL and PC in humans. Disclosures Ghobrial: BMS: Honoraria, Research Funding; Novartis: Honoraria; Celgene: Honoraria, Research Funding; Takeda: Honoraria; Noxxon: Honoraria; Amgen: Honoraria. Anderson:Oncoprep: Equity Ownership; Acetylon: Equity Ownership; Oncoprep: Equity Ownership; Gilead: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Acetylon: Equity Ownership; Millennuim: Membership on an entity's Board of Directors or advisory committees; Millennuim: Membership on an entity's Board of Directors or advisory committees; C4 Therapeutics: Equity Ownership; C4 Therapeutics: Equity Ownership; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees.

A Phase I Study of 177 lu-DOTA-HH1 (Betalutin) Radioimmunotherapy for Patients with Relapsed CD37+ Non-Hodgkin's B Cell Lymphoma

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3094-3094 ◽  
Author(s):  
Arne Kolstad ◽  
Ulf Madsbu ◽  
Jostein Dahle ◽  
Caroline Stokke ◽  
Tore Bach-Gansmo ◽  
...  
Keyword(s):  
Adverse Events ◽  
B Cell ◽  
Board Of Directors ◽  
Dose Level ◽  
Phase I Study ◽  
Cell Lymphoma ◽  
Employment Equity ◽  
Advisory Committees ◽  
Mantle Cell ◽  
Equity Ownership

Abstract Background and aim: The CD37 antigen is expressed at high levels predominantly by normal B cells and the majority of malignant B-cell lymphomas. Hence, this surface antigen represents an interesting therapeutic target for treatment of B-cell non-Hodgkin lymphomas (NHL). 177Lu-DOTA-HH1 (Betalutin™) is a novel anti-CD37 radioimmunoconjugate currently under clinical development. Betalutin™ consists of the β-emitting isotope Lutetium-177 (t/2 = 6.7 days) chelated to DOTA (a chemical linker) which is conjugated to the murine mAb HH1. Betalutin™ is delivered in a ready-to-use formulation at the study centers. Pre-clinical studies have demonstrated significant anti-tumor activity; both ex vivo and in models of human B-cell lymphomas in mice. Based on these results, a phase I study has been initiated in order to determine the maximum tolerated dose (MTD), overall safety and to explore tumor response. Methods: Patients with relapsed incurable CD37+ NHL of follicular grade I-IIIA, marginal zone, mantle cell, lymphoplasmacytic and small lymphocytic lymphomas with < 25% bone marrow infiltration and with platelet counts ≥ 150 x109/l were eligible for inclusion in the study. In order to deplete normal B cells patients first received a pre-treatment consisting of single infusions of rituximab (375 mg/m2) on day 1 and day 8. On day 29 the patients received a pre-dose infusion of HH1 (50 mg, cold CD37 antibody) followed by the radioimmunoconjugate 177Lu-DOTA-HH1administered as a 10 minute iv bolus. A 3 x 3 dose escalation design was used with 10 MBq/kg as the starting level. Patients were assessed for distribution of radioactivity by gamma camera wholebody scans and SPECT/CT. Clinical response was studied by 18F-FDG PET/CT, CT and bone marrow specimens. Evaluation of response was performed according to the NCI criteria of 1999 and 2007. Adverse events were monitored and scored in agreement with the NCI Common Terminology Criteria for Adverse Events (CTCAE) for toxicity grading. Results: A total often patients (9 follicular lymphoma,1 mantle cell lymphoma) have been treated according to protocol since the study was initiated in December 2012. The median number of prior therapies were 2 (range 1-7) and four out of ten patients had previously not responded to or progressed during treatment with rituximab as single agent. Serious adverse events were reported for four patients. Two patients developed thrombocytopenia requiring platelet transfusions and one of these patients had epistaxis. Another patient with a previous history of pulmonary embolism (PI) presented with pneumonia and PI. The fourth SAE was a transient case of atrial fibrillation, unlikely to be related to the study drug. Apart from these events, the most common toxicities were hematological, as expected with median time to nadir for platelets and neutrophils of 39 days and 48 days, respectively. Dose-limiting toxicity (DLT) was observed in all three patients treated at dose level 2 (20 MBq/kg), with grade III/IV neutropenia and/or thrombocytopenia, all reversible. However, no patients developed neutropenic fever. Based on the assumption that MTD is 15 MBq/kg, three patients are currently in follow-up after treatment at this dose level. With regard to efficacy, clinical responses have been observed at both dose level 1 (10 MBq/kg) and 2 (20 MBq/kg). At level 10 MBq/kg, two out of four patients had partial remissions, one had stable disease and one progressed. At level 20 MBq/kg two out of three patients obtained a complete remission and one had a partial remission. At dose level 15 MBq/kg efficacy results are pending. The first patient treated in this study has now been in stable remission with an observation time of 18 months. Conclusion: 177Lu-DOTA-HH1 in a single dose ready-to-use formulation has a favorable safety profile, mostly with hematological toxicities as expected. DLT was observed at dose level 20 MBq/kg, and dose level 15 MBq/kg is currently predicted to be the MTD for the phase II part of this trial. Complete and partial responses have been observed so far, hence, 177Lu-DOTA-HH1 targeting the CD37 antigen is a promising new candidate against NHL. Disclosures Kolstad: Nordic Nanovector: Membership on an entity's Board of Directors or advisory committees, Research Funding. Dahle:Nordic Nanovector AS: Employment, Equity Ownership, Patents & Royalties. Bruland:Nordic Nanovector AS: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees. Bolstad:Nordic Nanovector AS: Employment, Equity Ownership. Larsen:Nordic Nanovector AS: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Alfheim:Nordic Nanovector as: Employment, Equity Ownership. Holte:Nordic Nanovector AS: Membership on an entity's Board of Directors or advisory committees.

Herpes Zoster (HZ) Complicating Bortezomib Therapy of Relapsed/Refractory Indolent B-Cell and Mantle Cell Lymphoma: An Analysis of Two Phase II Trials.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2818-2818
Author(s):  
Vicki A. Morrison ◽  
Richard I Fisher ◽  
Andre Goy ◽  
Sven de Vos ◽  
Steven H. Bernstein ◽  
...  
Keyword(s):  
B Cell ◽  
Mantle Cell Lymphoma ◽  
Board Of Directors ◽  
Cell Lymphoma ◽  
Single Agent ◽  
Phase Ii Trials ◽  
Two Phase ◽  
Advisory Committees ◽  
Mantle Cell ◽  
Purine Analog

Abstract Abstract 2818 Background: The use of bortezomib-based therapy is known to be associated with an increased risk of HZ in patients (pts) with multiple myeloma, who have disease-related inherent immune defects. A 13% incidence of HZ occurrence in pts with relapsed/refractory MM who received single agent bortezomib has been previously reported (J Clin Oncol 2008; 26:4784-4790). However, the occurrence of HZ in bortezomib-treated pts with non-Hodgkin lymphoma (NHL) has not been previously examined. Methods: We reviewed clinical data from two phase II trials in which bortezomib therapy was administered to pts with relapsed/refractory mantle cell NHL or indolent B-cell NHL. The occurrence of HZ complicating their treatment course was delineated, and an analysis for potential predisposing risk factors was undertaken. Results: A total of 236 relapsed/refractory pts, median age 65 years (yrs), enrolled on these trials was examined. Mantle cell NHL pts (n=155) received single-agent bortezomib, 1.3 mg/m2, days (D) 1, 4, 8, 11, 21-D cycles; those with indolent B-cell NHL (n=81) received either bortezomib, 1.3 mg/m2, D 1, 4, 8, 11, 21-D cycles, plus rituximab, 375 mg/m2, D 1, 8, 15 (cycle 1) and D 1 (cycle 2) (n=41), or bortezomib, 1.6 mg/m2, D 1, 8, 15, 22, 35-D cycles, and rituximab, 375 mg/m2, D 1, 8, 15, 22 (cycle 1) (n=40). HZ occurred in 24 pts (10.2%) overall, with a comparable incidence in both disease subgroups. Median time to HZ occurrence was 39 (range, 11–206) days (< 2 cycles). Overall, 11% of pts had had a prior episode of HZ. Baseline demographic and clinical variables were examined, including age, gender, disease stage, baseline absolute neutrophil and lymphocyte counts, hemoglobin, lactate dehydrogenase, prior HZ, and number and types of prior therapies, to determine if any may predict for subsequent development of HZ. With regard to age, 71% of pts with HZ were age ≥65 yrs, compared to 48% without HZ (p=0.03). 63% of pts with HZ had received ≥2 lines of prior therapy, compared to 47% in those without HZ (p=0.15). 4% of pts with HZ had undergone prior stem cell transplantation, compared to 13% of pts without HZ. Of the pts with HZ, 25% had received prior purine analog therapy, compared to 9% of pts without HZ. The other baseline variables had no impact on the occurrence of HZ. In the 77 pts who responded to bortezomib protocol therapy (complete/partial responses), the incidence of HZ was 14%, compared to an 8% incidence of HZ in the 159 non-responders (p=0.15). Conclusions: HZ may complicate the course of relapsed/refractory indolent or mantle cell NHL pts receiving bortezomib-based therapies, with an incidence similar to the myeloma population. Pts who are elderly, more heavily-pretreated, or have received prior purine analog therapy may be at greater risk of this complication, and should be strongly considered for antiviral prophylaxis during such therapy. Disclosures: Morrison: Merck: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Genentech: Speakers Bureau; Pfizer: Speakers Bureau. Off Label Use: Discussion of Velcade in NHL subtypes other than mantle cell lymphoma is included. Fisher:Allos Therapeutics: Consultancy; CytoKinetics: Consultancy; GSK: Consultancy; MundiPharma: Consultancy; Seattle Genetics: Consultancy; Millennium Pharmaceuticals, Inc,: Consultancy. Goy:Millennium, Celgene, GSK and Genentech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Bernstein:Millennium Pharmaceuticals, Inc: Consultancy, Honoraria, Speakers Bureau. Boral:Millennium Pharmaceuticals, Inc.: Employment; Takeda Pharmaceuticals: Equity Ownership. Neuwirth:Millennium Pharmaceuticals, Inc.: Employment.

scholarly journals Systematic Reviews of the Clinical Efficacy and Safety of First-Line Treatments for Patients with Mantle Cell Lymphoma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5868-5868
Author(s):  
Neerav Monga ◽  
Jamie Garside ◽  
Matthew S. Davids ◽  
Constantine S. Tam ◽  
Katherine Ward ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Research Funding ◽  
Cell Lymphoma ◽  
Eligible Patient ◽  
High Dose ◽  
Efficacy And Safety ◽  
First Line ◽  
Advisory Committees ◽  
Treatment Regimens ◽  
Mantle Cell

Abstract Introduction Mantle cell lymphoma (MCL) is a rare and aggressive form of Non-Hodgkin's lymphoma (NHL) with poor survival outcomes. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is recommended as first-line therapy in younger patients. However the comparative efficacy of such regimens, and of alternative therapy options (for patients unable to tolerate chemotherapy + ASCT), remain unclear. A comprehensive understanding of the current evidence is therefore required. Methods Two systematic reviews (SRs) were developed to identify efficacy and safety data for therapies used in the first-line treatment of MCL. One review identified randomised controlled trials (RCTs) and the other non-randomised studies (NRSs). Searches were carried out in EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Clinical Trials electronic databases. Additionally, conference materials were screened from ASH, EHA, ESMO and ASCO proceedings from the last 2 years. All review methodologies were performed according to Cochrane best practice guidelines Results The RCT SR was run in August 2017 and updated in April 2018. Overall, 2,787 abstracts were screened. The SR included 9 full-text articles and data from 2 conference proceedings, together reporting a total of 7 independent studies. Across the RCTs, the most commonly investigated treatment regimens were rituximab + cyclophosphamide + doxorubicin + vincristine + prednisone (R-CHOP), and bendamustine + rituximab (BR). Frequently reported primary endpoints were response rates and progression-free survival (PFS). Table 1 presents the PFS and overall survival (OS) data reported in the included RCTs. Data from the RCT reporting on intensive induction chemotherapy followed by ASCT are separated from regimens that did not include ASCT. There were notable differences in median PFS rates, between both patients receiving ASCT versus patients not receiving ASCT and also between the two ASCT treatment arms. In pharmacotherapy studies, PFS ranged from 14.4 to 35.4 months, whereas the two arms of the ASCT RCT reported 51.6 and 109.2 months, respectively. Similar trends were observed in OS: the only result for patients undergoing ASCT (117.6 months) was higher than any result reported in patients not receiving transplant (range 40 - 60 months). However, study heterogeneity may affect the appropriateness of directly comparing these results. Frequently reported grade 3-4 adverse events included anemia, infusion-related reactions, nausea, neutropenia and thrombocytopenia (four of seven RCTs reported each event). The NRS SR was run in April 2018. A total of 3,290 abstracts were screened and 75 full papers were assessed. The SR included 25 full-text articles and 6 conference proceedings, together reporting a total of 18 independent single-arm studies. Several of the NRSs investigated treatment regimens that have not been described in RCT studies, including: R-CHOP with alternating or sequential rituximab + cytarabine (maxiCHOP), and cyclophosphamide + vincristine + doxorubicin + dexamethasone alternating with high dose methotrexate or cytarabine + rituximab (hyperCVAD + R). Across the NRSs, the longest median PFS was 8.5 years (102 months), in patients treated with maxiCHOP (who were young/ASCT-eligible patients). This outcome was reported in a patient population who had responded to induction therapy and were treated with consolidative ASCT. Across all studies there was heterogeneity in the eligible patient population, with some studies focusing on unfit patients and others focusing on high-dose-therapy-eligible patient populations. Many studies also reported maintenance or consolidation treatments, which would influence the long-term outcomes of the patients. Conclusions These SRs highlight the paucity of directly comparable evidence on the efficacy and safety of therapies for patients with MCL. Although there are some marked differences in patient outcomes according to therapy regimen, considerable heterogeneity in study design and patient populations make direct comparison difficult. Despite this, these SRs highlight that MCL remains a difficult subtype of NHL to treat, with short survival highlighting the high unmet need. With new and emerging therapies, additional research is essential to understand optimal regimens for first-line MCL. Table 1. Table 1. Disclosures Monga: Janssen Pharmaceutica NV: Employment. Garside:Janssen Pharmaceutica NV: Employment. Davids:Merck: Consultancy; Roche/Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Consultancy, Research Funding; BMS: Research Funding; Surface Oncology: Research Funding; Celgene: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; AbbVie, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees; Verastem: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Tam:BeiGene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Ward:Janssen Pharmaceutica NV: Consultancy. Quigley:Janssen Pharmaceutica NV: Consultancy. Parisi:Janssen: Employment. Tapprich:Janssen Pharmaceutica NV: Employment.

scholarly journals Co-Expression of SYK and ZAP70 Subverts Negative B-Cell Selection and Enables Oncogenic Signaling in Multiple B-Cell Malignancies

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 295-295
Author(s):  
Teresa Sadras ◽  
Mickaël Martin ◽  
Lauren Kim-Sing ◽  
Jevon Cutler ◽  
Gal Lenz ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Death ◽  
B Cells ◽  
B Cell ◽  
Cell Lymphoma ◽  
Cell Selection ◽  
B Cell Malignancies ◽  
Close Proximity ◽  
Mantle Cell ◽  
Bcr Signaling

B-cells are under intense selective pressure to eliminate autoreactive or premalignant clones. B-cell receptor (BCR) signals are required for survival, however, BCR-signaling exceeding maximum thresholds often reflects signaling from an autoreactive BCR or a transforming oncogene and triggers negative selection and cell death. The tyrosine kinase SYK initiates BCR-downstream signaling in B-cells while its close relative ZAP70 is almost exclusively expressed in T-cells. Interestingly, the segregation of SYK to B-cells and ZAP70 to T-cells is less confined in malignant lymphopoiesis suggesting that the balance of these related kinases may alter signaling output in disease and contribute to development of leukemia. As previously shown in B-cell chronic lymphocytic leukemia (B-CLL), we identified aberrant ZAP70 expression as a frequent feature in multiple other B-cell malignancies that depend on survival signals from a functional (pre-) BCR (E2A-PBX1+ pre-B ALL, and mantle cell lymphoma) or harbor oncogenic mimics of the BCR (BCR-ABL1+ B-ALL). Studying SYK and ZAP70 expression by single-cell Western blot, co-expression of the two tyrosine kinases was extremely rare in normal B- and T-cell populations. In contrast, &gt;50% of tumor B-cells in mantle cell lymphoma, pre-B ALL and CLL co-expressed SYK and ZAP70. Despite their structural similarities, genetic deletion and engineered reconstitution of SYK and ZAP70 in human B-cell lymphoma cells revealed striking functional differences. Proximity-dependent biotin identification (BioID) analyses identified that SYK, but not ZAP70, engaged the PI3K pathway via interaction with CD19. Consistent with this, reconstitution with SYK and SYK-ZAP70 but not ZAP70 alone promoted survival and proliferation. Detailed analysis of BCR-mediated cascades in lymphoma cells expressing SYK, ZAP70 or SYK-ZAP70 established that ZAP70 is only weakly efficient at propagating BCR-mediated calcium and downstream pathway activation in B-cells. Strikingly, co-expression of ZAP70 with SYK resulted in re-wired BCR-signaling of intermediate strength: compared to cells expressing only SYK, SYK-ZAP70 co-expressing cells had markedly reduced activation of the BLNK-BTK-PLCγ pathway, further reflected in BCR-induced Ca2+ signaling with delayed onset, lower amplitude but longer duration. In this way, we speculated that SYK and ZAP70 may be present within close proximity at the apex of BCR-initiated interactions, and hence compete for downstream substrates resulting in a re-wiring of classic signaling programs propagated normally by SYK. To explore this, we utilized proximity ligation assays (PLA) to monitor the proximity of SYK and ZAP70 in resting or BCR-stimulated B-cells, and found that SYK and ZAP70 co-exist within close proximity consistent with the view that varying levels of these kinases may alter B-cell signaling output. Functional experiments further showed that phosphomimetic activation of SYK, but not ZAP70, induced hyperactivation of PI3K-signaling and acute BTK-mediated cell death in pre-B ALL cells. In line with altered BCR-signaling strength and quality in SYK and ZAP70 co-expressing cells, over-expression of Zap70 in pre-B ALL cells rescued auto-immune checkpoint activation induced by hyper-activation of BCR-associated signaling. To study functional consequences of SYK-ZAP70 co-expression during normal B-cell development, we generated a novel knock in Zap-70+/Mb1-Cre+mouse model, to induce conditional expression of Zap70 in the B cell compartment from the proB stage. Consistent with compromised central tolerance checkpoints, Syk-Zap70 co-expressing pro/pre-B and immature B-cells had reduced spontaneous apoptosis rates and gave rise to autoantibody production against multiple self-antigens. Importantly, our findings highlight a previously unrecognized role for ZAP70 in oncogenic BCR-signaling and we conclude that the co-expression of ZAP70 mitigates the ability of SYK, downstream of an autoreactive BCR or a transforming oncogene, to trigger negative B-cell selection and cell death (Figure 1). Disclosures Weinstock: Celgene: Research Funding. Meffre:AbbVie: Consultancy, Other: Grant.

scholarly journals First-in-Human, Phase 1/2 Trial to Assess the Safety and Clinical Activity of Subcutaneous GEN3013 (DuoBody®-CD3×CD20) in B-Cell Non-Hodgkin Lymphomas

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 758-758 ◽  
Author(s):  
Pieternella Lugtenburg ◽  
Rogier Mous ◽  
Michael Roost Clausen ◽  
Martine E.D. Chamuleau ◽  
Peter Johnson ◽  
...  
Keyword(s):  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Board Of Directors ◽  
Dose Escalation ◽  
Research Funding ◽  
Clinical Activity ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Introduction: CD20-specific monoclonal antibodies (mAbs) have demonstrated efficacy in the treatment of B-cell non-Hodgkin lymphomas (B-NHL); however, a significant proportion of patients (pts) present with refractory disease or will experience relapse. GEN3013 (DuoBody®-CD3×CD20) is the first subcutaneously administered IgG1 bispecific antibody (bsAb) that targets the T-cell surface antigen CD3 and the B-cell surface antigen CD20, triggering T-cell-mediated killing of B cells. In vitro, GEN3013 efficiently activates and induces cytotoxic activity of CD4+ and CD8+ T cells in the presence of B cells (Hiemstra et al. Blood 2018), and results in long-lasting depletion of B cells in cynomolgus monkeys. Subcutaneous (SC) GEN3013 in cynomolgus monkeys resulted in lower plasma cytokine levels, and similar bioavailability and B-cell depletion, compared with intravenous administration. GEN3013 has higher potency in vitro than most other CD3×CD20 bsAbs in clinical development (Hiemstra et al. HemaSphere 2019). SC GEN3013 in pts with B-NHL is being evaluated in a first-in-human, Phase 1/2 trial (NCT03625037), which comprises a dose-escalation part and a dose-expansion part. Here we report preliminary dose-escalation data. Methods: Pts with CD20+ B-NHL with relapsed, progressive, or refractory disease following anti-CD20 mAb treatment, and ECOG PS 0-2 were included. During dose escalation, pts received SC GEN3013 flat dose in 28-day cycles (q1w: cycle 1-2; q2w: cycle 3-6; q4w thereafter) until disease progression or unacceptable toxicity. Risk of cytokine release syndrome (CRS) was mitigated with the use of a priming dose and premedication with corticosteroids, antihistamines, and antipyretics. Primary endpoints were adverse events (AEs) and dose-limiting toxicities (DLTs). Secondary endpoints included pharmacokinetics (PK), immunogenicity (anti-drug antibodies [ADA]), pharmacodynamics (PD) (cytokine measures; laboratory parameters), and anti-tumor activity (tumor size reduction; objective and best response). Results: At data cut-off (June 28, 2019), 18 pts were enrolled into the dose-escalation part of the trial, with safety data available for pts receiving doses starting at 4 µg. Most pts had diffuse large B-cell lymphoma (DLBCL; n=14) and were heavily pre-treated; 10 pts had received ≥3 prior lines of therapy (overall median [range]: 3 [1-11]). The median age was 58.5 years (range: 21-80), and 13 pts were male. At a median follow-up of 1.9 months, pts received a median of 5 doses (range: 1-14); treatment is ongoing in 6 pts. Twelve pts discontinued treatment due to progressive disease. Six pts died (2 during treatment, 4 during survival follow-up), all due to disease progression and unrelated to treatment. The most common (n≥5) treatment-emergent AEs were pyrexia (n=8), local injection-site reactions (n=7), diarrhea (n=5), fatigue (n=5), and increased aspartate aminotransferase (n=5). The most common Grade (G) 3/4 AEs were anemia (n=3) and neutropenia (n=3). Despite increasing GEN3013 doses, all CRS events were non-severe (initial observation: 3/8 pts, G1: n=1, G2: n=2; following modification of premedication plan [corticosteroids for 3 days]: 6/10 pts, G1: n=4, G2: n=2). Increases in peripheral cytokine (IL6, IL8, IL10, IFNγ, TNFα) concentrations after GEN3013 dosing correlated with clinical symptoms of CRS in most pts. No pts had tumor lysis syndrome or neurological symptoms. No DLTs were observed. GEN3013 PK profiles reflect SC dosing; Cmax occurred 2-4 days after dosing. No ADAs were detected. PD effects following GEN3013 dosing were observed at dose levels as low as 40 µg and included rapid, complete depletion of circulating B cells (if present after prior anti-CD20 therapy) and peripheral T-cell activation and expansion. The first evidence of clinical activity was observed at a dose level of 120 µg, with complete metabolic response observed in a pt with DLBCL. Conclusions: Subcutaneously administered GEN3013, a potent CD3×CD20 bsAb, shows good tolerability and early evidence of clinical activity at low dose levels in heavily pretreated pts with relapsed or refractory B-NHL. All CRS events were non-severe and did not lead to discontinuation. No DLTs were observed. Dose escalation is ongoing; updated data will be presented. Dose expansion will begin upon determining the recommended Phase 2 dose (RP2D) (NCT03625037). Disclosures Lugtenburg: Janssen Cilag: Honoraria; Roche: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria; Servier: Consultancy, Honoraria, Research Funding; Genmab: Consultancy, Honoraria; BMS: Consultancy; Takeda: Consultancy, Honoraria, Research Funding. Mous:Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Sandoz: Honoraria; Roche: Honoraria; Abbvie: Honoraria; Takeda: Honoraria, Research Funding; Janssen Cilag: Consultancy, Honoraria; MSD: Honoraria; Gilead: Consultancy, Honoraria, Research Funding. Clausen:Abbvie: Other: Travel grant to attend ASH 2019. Johnson:Boehringer Ingelheim: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Honoraria; Epizyme: Honoraria, Research Funding; Incyte: Honoraria; Takeda: Honoraria; Genmab: Honoraria; Bristol-Myers Squibb: Honoraria; Kite: Honoraria; Novartis: Honoraria. Rule:Janssen: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Astra-Zeneca: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria; TG Therapeutics: Consultancy, Honoraria; Napp: Consultancy; Kite: Consultancy. Oliveri:Genmab: Employment, Equity Ownership. DeMarco:Genmab: Employment, Equity Ownership. Hiemstra:Genmab: Employment, Equity Ownership, Other: Warrants. Chen:Genmab: Employment. Azaryan:Genmab: Employment. Gupta:Genmab: Employment, Equity Ownership. Ahmadi:Genmab Inc: Employment, Other: stock and/or warrants. Hutchings:Incyte: Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Genmab: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Janssen: Research Funding; Pfizer: Research Funding.

scholarly journals Adoptive T-Cell Therapy with TCL1-Specific TCR for B-Cell Lymphomas

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3488-3488
Author(s):  
Jinsheng Weng ◽  
Kelsey Moriarty ◽  
Yong Pan ◽  
Man Chun John MA ◽  
Rohit Mathur ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Therapy ◽  
B Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Cell Lymphoma ◽  
B Cell Malignancies ◽  
Advisory Committees ◽  
T Cell Therapy

Abstract Chimeric antigen receptor (CAR)-modified T-cell therapy targeting CD19 induces high response rates in patients with relapsed or refractory B-cell lymphomas. However, about 60% of patients experience primary or secondary resistance after CD19-targeted CAR T-cell therapy and a major of cause of failure appears to be due to loss of CD19 expression on the tumor. Therefore, novel targets for adoptive T-cell therapeutic approaches are needed to further improve clinical outcome in these patients. T-cell leukemia/lymphoma antigen1 (TCL1) is an oncoprotein that is overexpressed in multiple B-cell malignancies including follicular lymphoma (FL), mantle cell lymphoma (MCL), diffuse large B-cell lymphoma (DLBCL), and chronic lymphocytic leukemia (CLL). Importantly, it has restricted expression in only a subset of B cells among normal tissues. We previously identified a TCL1-derived HLA-A2-binding epitope (TCL170-79 SLLPIMWQLY) that can be used to generate TCL1-specific CD8+ T cells from peripheral blood mononuclear cells of both HLA-A2+ normal donors and lymphoma patients. More importantly, we showed that the TCL1-specific CD8+ T cells lysed autologous primary lymphoma cells but not normal B cells (Weng et al. Blood 2012). To translate the above discovery into clinic, we cloned the T-cell receptor (TCR) alpha and beta chains from a TCL1-specific CD8+ T-cell clone and showed that this TCL1-TCR could be transduced into polyclonal donor T cells using a lentiviral system with a transduction efficiency of >40% as determined by TCL170-79 tetramer positive T cells. Furthermore, we demonstrated that the TCL1-TCR-transduced T cells recognized T2 cells pulsed with TCL170-79 peptide producing IFN- γ >8 ng/ml and IL-2 >350 ng/ml but were not reactive to control HIV-Gag peptide (IFN- γ <0.1 ng/ml and IL-2 <0.2 ng/ml). The TCL1-TCR-transduced T cells recognized TCL170-79 peptide pulsed onto T2 cells at a concentration of 1-10 nM (IL-2 >10 ng/ml) suggesting it has moderate to high avidity. Importantly, TCL1-TCR-transduced T cells lysed HLA-A2+ (up to 43% lysis of Mino and 25% lysis of Jeko-1 at 40:1 Effector:Target ratio) but not HLA-A2- lymphoma cell lines (5.5% lysis of HLA A2- Raji and 2.3% lysis of Daudi at 40:1 Effector:Target ratio). TCL1-TCR-transduced T cells were also cytotoxic to HLA-A2+ primary lymphoma tumor cells (up to 48% lysis of CLL, 43% lysis of FL, 41% lysis of DLBCL, 46% lysis of splenic marginal zone lymphoma, and 11% lysis of MCL at 40:1 Effector:Target ratio) but not normal B cells derived from the same patients. Lastly, TCL1-TCR transduced T cells showed high efficacy in in vivo models. Adoptive transfer of the TCL1-TCR-tranduced T cells significantly reduced lymphoma tumor growth and extended survival in Mino mantle cell lymphoma cell line xenograft model (48% survival in TCL1-TCR-T treated group vs. 12.5% survival in control group at 10 weeks n=7-8 mice/group; P=0.02). Collectively, our data suggest that the high expression in B-cell tumors, restricted expression in normal tissues, and presence of an immunogenic CD8 T-cell epitope, make TCL1 a target for T cell-based therapeutic approaches in multiple B-cell malignancies. Our results also demonstrate that the TCL1-specific TCR-transduced T cells may serve as a novel adoptive immunotherapy approach for the treatment of patients with various B-cell malignancies (including FL, MCL, DLBCL, CLL). Acknowledgments: This study is supported by MD Anderson Moon Shot Program and CPRIT and the National Natural Science Foundation of China Grant (No. 81570189) Disclosures Neelapu: Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cellectis: Research Funding; Poseida: Research Funding; Merck: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta: Research Funding; Karus: Research Funding; Bristol-Myers Squibb: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees; Unum Therapeutics: Membership on an entity's Board of Directors or advisory committees.

scholarly journals Unravelling the Heterogeneity of Mantle Cell Lymphoma Ecosystem By Single Cell RNA Sequencing

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4118-4118
Author(s):  
Makhdum Ahmed ◽  
Hui Guo ◽  
Shaojun Zhang ◽  
Lalit Sehgal ◽  
Preetesh Jain ◽  
...  
Keyword(s):  
B Cells ◽  
Tumor Microenvironment ◽  
B Cell ◽  
Single Cell ◽  
Research Funding ◽  
Cell Lymphoma ◽  
Clonal Evolution ◽  
Advisory Committees ◽  
Cell Clones ◽  
Mantle Cell

Abstract Background: Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma that is incurable. MCL has a complex ecosystem of malignant B-cells and stromal and immune cells that play a supporting role for tumor growth, ultimately leading to the potential re-emergence of the disease. The tumor microenvironment has been reported as a crucial factor in MCL pathogenesis and progression. Thus, if we can identify the tumor microenvironment components and define the characteristics of malignant and non-malignant cells, this will pave the way for studying clonal evolution of MCL in vivo. Methods: Both pre- and post-treatment, fresh tumor biopsy samples of MCL were obtained. The cells were dissociated and re-suspended in PBS with >10% serum. A final concentration of 1,200 cells/uL were used for single cell sorting in the chromium system (10X Genomics, California). We sequenced the mRNA in the NextSeq 500 platform. All analysis was conducted using R-programming language (version 3.4). Results: From four MCL patients (L1-L4), we obtained 9,400 cells. Three of the four samples were collected through apheresis (i.e., L1-L3), and one sample (i.e., L4) from surgical biopsy of the involved lymph node. One patient had known TP53 mutated status (i.e., L1) and another patient had CCND1 translocation (i.e., L2). From the apheresis samples (L1-L3), the proportion of lymphocytes was 87%, 68% and 65%. We identified 10 defined clusters of cells based upon their gene expression from all four samples. Six of the 10 clusters were clonal B-cells with strong expression of CCND1, CD79A and CD79B. We also identified clonal T-cells (both CD8+ and CD4+) and monocyte/macrophage clusters. SOX11 expression was absent in one B-cell clone, indicating this clone may be SOX11-negative MCL. The monocyte-macrophage cluster demonstrated strong BCL2 expression, which was not expressed by the B-cells clones. CD19 expression was ubiquitous among the B-cell clones but weaker as compared with other B-cell markers. When the signaling was compared among the four samples, the chemo-resistant cells (sample L1) demonstrated upregulation of NOTCH1 signaling, DNA-damage repair, interferon-alpha response, MYC targets and the HIF1A pathway. Two cell clones did not express any canonical markers and were not identified as a defined cluster. Conclusions: We identified meaningful sub-populations of MCL that define the tumor microenvironment. There is considerable inter-tumor and intra-tumor heterogeneity of MCL at a single cell resolution, which indicates that developing a uniform treatment regimen may prove to be difficult. Ubiquitous expression of CD79A or CD79B may help guiding precision medicine such as the development of novel CAR-T cell therapy. Longitudinal follow up of the same patients may define clonal evolution of MCL and unravel the spatio-temporal interplay. Figure. Figure. Disclosures Wang: AstraZeneca: Consultancy, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Kite Pharma: Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; MoreHealth: Consultancy; Novartis: Research Funding; Acerta Pharma: Honoraria, Research Funding; Dava Oncology: Honoraria; Juno: Research Funding; Pharmacyclics: Honoraria, Research Funding.

scholarly journals In Vitro-Selected Nanobody-Based Cellular Therapy Targeting CD72 for Treatment of Refractory B-Cell Malignancies

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1337-1337
Author(s):  
Matthew Nix ◽  
Yu-Hsiu T. Lin ◽  
Huimin Geng ◽  
Makeba Marcoulis ◽  
Paul Phojanakong ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Surface ◽  
B Cell ◽  
Board Of Directors ◽  
B Cell Malignancies ◽  
Advisory Committees ◽  
Car T ◽  
Equity Ownership

Introduction: B-cell acute lymphoblastic leukemia (B-ALL) patients that harbor rearrangements of the Mixed-lineage leukemia gene (MLLr; also known as KMT2Ar) have particularly dismal clinical outcomes. Although CAR T immunotherapies targeting CD19 have shown impressive responses treating MLLr B-ALL and other B cell malignancies, relapse, often with loss of relevant CD19 epitope, remains a major clinical concern. The mixed results of CD19 CAR T as a monotherapy underscores the need to pursue additional immunotherapy targets and novel therapeutic modalities for high-risk patients. Results and Methods: Data with existing CAR-T's suggest that increased target antigen density frequently correlates with increased tumor elimination. Therefore, we aimed to define the cell surface proteomic landscape of B-ALL to identify novel, MLLr-enriched candidates for targeted immunotherapy of this poor-prognosis subtype. As an initial screen, using N-glycoprotein capture and mass spectrometry, we quantified differentially abundant cell surface proteins in MLLr (n= 4) versus non-MLLr (n= 5) B-ALL cell lines (Figure 1). Label-free proteomics (n= 3 replicates) quantified &gt;900 high-confidence membrane proteins (FDR=0.05). Principal component analysis identified unique cell surfaceome signatures between B-ALL subtypes, implying different surface landscapes associated with specific genetic alterations. The MLLr B-ALL "surfaceome" is notably characterized by increased expression of adhesion molecules not identified by RNA-sequencing alone. We focused on CD72 as a novel immunotherapy target given significant enrichment on MLLr B-ALL vs. other B-ALL subtypes, near equivalent antigen density to CD19, undetectable expression on HSPCs, T-cells, and other normal tissues, and reported widespread expression on other mature B-cell malignancies. Analysis of transcriptome and ChIP-seq data suggested increased CD72 expression in MLLr B-ALL is not regulated directly by the MLL-AF4 oncoprotein but instead a function of increased CD72 expression at pro-B-cell stage. Flow cytometry and immunohistochemistry on primary samples confirmed high expression of CD72 both in MLLr B-ALL as well as DLBCL. Recombinant CD72 ECD was panned against a fully in vitro nanobody yeast display library (McMahon et al., Nat Struct Mol Biol(2018)) resulting in isolation of multiple unique, highly-specific CD72 nanobody binders with KD's &lt; 5nM. Nanobodies were incorporated into 2nd generation CAR constructs and transduced into normal donor CD8+ T-cells and assessed in vitro for tumor cell lysis, cytokine release, and exhaustion marker expression. Nanobody clone Nb.D4 outperformed others in lysis of B-ALL and DLBCL cells lines displaying a broad range of CD72 expression, had no activity versus CD72 negative cells, and showed similar efficacy to that found with a clinically-used CD19 CAR. To assess in vivo activity, CD72(Nb.D4) CAR-T's at 1:1 CD4:CD8 ratio were injected at an effector:tumor ratio of 5:1 into tumor-bearing NSG mice (luciferase-labeled SEM or MLLr PDX). In vivo results confirmed strong anti-tumor effect of CD72 nanobody CAR-T's, equivalent to clinical CD19 CAR, and significantly increased survival in mice (Figure 2). A CRISPR interference-generated antigen escape model of CD19 was also effectively eliminated by CD72 CAR-T's. We also introduce "antigen escape profiling", where cell surface proteomics of a CRISPRi CD72-knockdown model demonstrated extensive surfaceome rewiring with potential implications for leukemia cell trafficking and adhesion in the setting of acquired resistance. Given CD72's role as a BCR signaling inhibitory receptor, we are currently examining its influence on proximal B-cell receptor signaling and relationship to combination therapies affecting this pathway. Conclusions:By characterizing the surface proteomic landscape of B-ALL, we develop a resource for the research community and identify CD72 as a promising therapeutic target. We demonstrate that a novel, fully recombinant nanobody library can generate potent cellular therapies, which may be extended to other targets in the future. We anticipate that antigen escape profiling will prove broadly useful for anticipating mechanisms of resistance to novel immunotherapies. CD72 CAR-T's are a promising strategy across a range of B-cell malignancies, particularly those refractory to CD19 therapy. Disclosures Nix: UCSF: Patents & Royalties. Wiita:UCSF: Patents & Royalties; Indapta Therapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Protocol Intelligence: Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

Sign in / Sign up

Export Citation Format

Share Document