Faculty Bibliography

Despite recent therapeutic advances in the management of non-Hodgkin lymphoma (NHL), up to 50% of patients with diffuse large B-cell lymphoma (DLBCL) relapse after first line therapy, and for DLBCL patients who relapse within 12 months after subsequent stem cell transplant (SCT), the median overall survival (OS) is 6.3 months. Recently, chimeric antigen receptor (CAR) T-cell therapy has shown remarkable activity in relapsed DLBCL with complete response (CR) rate of 40% and 54% for the two of the FDA-approved CAR T-cell products, tisagenlecleucel and axicabtagene ciloleucel, respectively. However, at a median follow-up of 18 months, only 36% of patients treated with tisagenlecleucel remained in CR; with longer follow-up for axicabtagene ciloleucel the median progression free survival (PFS) was 5.9 months. Immune escape and immune evasion are primary mechanisms of CAR-T resistance; clearly improvements are needed to increase response rate and cure. While CRISPR-based loss-of-function screens have shown promise for high-throughput identification of genes that modulate T-cell response, these methods have been limited thus far to negative regulators of T-cell functions, and raise safety concerns due to the permanent nature of genome modification. Here we identify positive T-cell regulators via overexpression of ~12,000 barcoded human open reading frames (ORFs). Using this genome-scale ORF screen, we found modulator genes which increased primary human CD4+ and CD8+ T-cell proliferation, including activation markers like CD25 and CD40L, and secretion of key cytokines like interleukin-2 and interferon-gamma. In addition, we developed a single-cell genomics method (OverCITE-seq) for high-throughput quantification of the transcriptome and surface proteome in ORF-engineered T-cells. The top-ranked ORF, lymphotoxin beta receptor (LTBR), is typically expressed in a subset of myeloid cells but absent in lymphocytes. When expressed in T-cells, LTBR induces a profound transcriptional remodelling, resulting in increased resistance to exhaustion and activation-induced apoptosis, as well as upregulation of a plethora of proinflammatory cytokines, co-stimulatory molecules and antigen presentation machinery. In order to investigate the mechanism of action of LTBR, we developed an epistasis assay which allows for simultaneous gene knockout and LTBR overexpression in primary T cells. Thus, LTBR appears to induce both canonical and non-canonical NFkB pathways - but the phenotype observed in T cells is dependent only on the former. Finally, we co-expressed several top-ranked genes, including LTBR, with FDA approved CD19-targeting CARs utilizing either 4-1BB or CD28 co-stimulatory domains. In line with previous results, co-expression of top-ranked ORFs increased proinflammatory cytokine secretion and cytotoxicity against CD19+ positive cancer cell lines. This functional improvement was also observed when top-ranked ORFs and CARs were delivered to T cells isolated from DLBCL patients as shown in Figure 1. Our results provide several strategies for improving next generation CAR T-cell therapies via induction of new synthetic cell programs which may optimize immune activation and enhance the efficacy of these important therapies, a high priority for patients with relapsed and refractory DLBCL and other lymphomas. [Formula presented] Disclosures: Mimitou: Immunai: Current Employment. Smibert: Immunai: Current Employment. Diefenbach: Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; IMab: Research Funding; Gilead: Current equity holder in publicly-traded company; Celgene: Research Funding; AbbVie: Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Merck Sharp & Dohme: Consultancy, Honoraria, Research Funding; IGM Biosciences: Research Funding; Morphosys: Consultancy, Honoraria, Research Funding; MEI: Consultancy, Research Funding; Perlmutter Cancer Center at NYU Langone Health: Current Employment; Incyte: Research Funding; Trillium: Research Funding; Seattle Genetics: Consultancy, Honoraria, Research Funding; Genentech, Inc./ F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Research Funding. Sanjana: Qiagen: Consultancy; Vertex: Consultancy.
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Background Classical Hodgkin lymphoma (cHL) is characterized by rare, malignant Hodgkin/Reed Sternberg (HRS) cells that shape their microenvironment (TME) to inhibit anti-tumor immune response. Systemic immune dysregulation may influence treatment response and toxicity, but the systemic influence of the TME is less well described. The wide variety of proteins measured in high-parmater flow cytometry make it a powerful tool for immune monitoring, but presents challenges in immuno-monitoring. Combinatorial expression of these proteins defines cell types that may influence disease. TerraFlow is a fully automated data analysis platform that evaluates millions of phenotypes and selects the populations that best predict clinical variables. The analysis can be performed using classical Boolean gates or a non-gating approach that approximates gates without using manual thresholds, allowing immunophenotypes to be comprehensively surveyed for disease associations. The platform was used to find phenotypes that discriminate healthy versus cHL patients (AUC = 1) and pre versus post treatment patient phenotypes(AUC = 0.79). Methods Human Subjects: Informed consent was obtained from cHL patients (N=44) treated at the Perlmutter Cancer Center (PCC) at NYU Langone Health and New York Presbyterian Weil Cornell (NYP) between 2011 and 2016. Blood samples were drawn at multiple time-points, for this study pre-treatment and 3 month post-treatment samples were used. Age-matched, cryopreserved healthy donor PBMC (n=25) were obtained from STEMCELL Technologies (Cambridge, MA).Patient-derived blood was processed for isolation of PBMC, stained analyzed on a Symphony Flow Cytometer (BD Biosciences, San Jose, CA). Analysis: Data was analyzed using an original platform called terraFlow. Many immune cell subsets are defined by the combinations of proteins they express. TerraFlow systematically evaluates millions of cell types by generating every possible combination of 1 to 5 markers. A network-based algorithm then selects the "best" phenotype from each set of inter-related combinations based on statistical power and ease of interpretation. Each phenotype is defined using a minimal gating strategy that can be replicated in a diagnostic panel or cell sorter. Together, phenotypes describe all the major differences between patient groups. A new platform developed by Epistemic AI was used to mine scientific literature and interpret selected phenotypes. Results We observed clear perturbations in the cHL systemic T-cell compartment pre-treatment as shown in Figure 1. These include higher levels of activated (CD278+), exhausted (CD366+, PD1+, CD152+), and suppressive (GITR+) T-cells compared to healthy donors, and diminished levels of T-cells producing effector cytokines (like IFNgamma and IL4). Subsets of cytokine-producing cells that co-express markers of exhaustion (i.e., TNF+ CD366+ cells) are also elevated in cHL patients. Finally, T-cells expressing CD127 a receptor for IL7 involved in homeostatic renewal of cells and observed on naive and central memory T-cells are reduced. Taken together, these findings suggest that in cHL the systemic T-cell compartment is shifted toward a more exhausted profile, and away from less differentiated cells, with the potential for self-renewal. Our data also demonstrates a shift from T-helper 1 and T-helper 2 type toward T-helper 17 cells suggesting that T-cell effector function may be reduced. Conclusion Using a novel data analysis platform, TerraFlow we demonstrate dysregulation in systemic T cell function in cHL patients pre-treatment that persists within 3 months of completing therapy. Associations of phenotypes with clinical variables, and post-treatment phenotypes will be described in detail at the meeting. Our results detail new immunotherapy and biomarker research targets, and suggest novel strategies for combination therapies. [Formula presented] Disclosures: Li: BD Bioscience: Current Employment. Ruan: Kite Pharma: Consultancy; AstraZeneca: Research Funding; BMS: Consultancy, Research Funding; Daiichi Sankyo: Consultancy, Research Funding; Pharmacyclics: Research Funding; Seagen: Consultancy. Diefenbach: Incyte: Research Funding; Trillium: Research Funding; Celgene: Research Funding; IGM Biosciences: Research Funding; Seattle Genetics: Consultancy, Honoraria, Research Funding; Gilead: Current equity holder in publicly-traded company; AbbVie: Research Funding; Perlmutter Cancer Center at NYU Langone Health: Current Employment; MEI: Consultancy, Research Funding; Genentech, Inc./ F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; IMab: Research Funding; Morphosys: Consultancy, Honoraria, Research Funding; Merck Sharp & Dohme: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding.
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Introduction: IGM-2323 is the first engineered high-affinity, high-avidity bispecific IgM monoclonal antibody TCE to be tested in the clinic. It has 10 binding domains for CD20 and a single binding domain for CD3 and is designed to bind irreversibly to CD20-high and low-expressing cells with more physiologic stimulation to T cells, which may mitigate cytokine release syndrome (CRS)-related toxicity and broaden the therapeutic window. IGM-2323 may act by multiple mechanisms: T-cell dependent cytotoxicity, complement dependent cytotoxicity, and enhanced immune modulation via IFNgamma-dominant cytokine stimulation. This phase 1 study is exploring the safety and activity of IGM-2323 using a dose titration schedule intended to optimize repeatable immune stimulation while minimizing toxicity.
Method(s): This first-in-human Phase 1 study is a global, multicenter, open-label, dose escalation evaluating safety, tolerability, PK, and preliminary efficacy (NCT04082936). Adults with relapsed or refractory CD20 ⁺ B-cell NHL with >= 2 prior systemic therapies, adequate organ function, and ECOG 0-1 are eligible. IGM-2323 is given IV on Days 1, 8, and 15 of 21-day cycles until disease progression or unacceptable toxicity. Treatment can continue beyond progression if the patient (pt) has benefitted from treatment and intra-patient dose escalation is allowed. This study also utilizes a dose titration scheme where a starting dose is given on Day 1, then higher subsequent doses...
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Context: Follicular lymphoma (FL) often presents with recurrent relapses. Treatment options for patients (pts) with FL who have received >=2 prior lines of therapy are limited, and prognosis is poor. The safety and efficacy of mosunetuzumab, a full-length, fully humanized IgG1 CD20/CD3 bispecific antibody is currently being investigated in an ongoing open-label, multicenter, Phase I/Ib, dose-escalation and expansion trial in relapsed/refractory (R/R) B-cell lymphoma (GO29781; NCT02500407).
Objective(s): To present updated data from the R/R FL cohort.
Method(s): Pts received intravenous mosunetuzumab step-up doses in cycle (C) 1, days (D) 1 and 8, then the target dose on D15 and D1 of each subsequent 21-day cycle (Group B); treatment continued for <=17 cycles.
Result(s): As of January 21, 2020, mosunetuzumab 0.4/1.0/2.8 mg to 1/2/13.5 mg (C1D1/8/15 dose levels) was given to 62 pts with FL who received >=2 prior systemic therapies. Pts had a median age of 59 (27-85) years, median number of 3 (2-11) prior therapies; 33 pts (53%) were double refractory, 30 (48%) had progression of disease within 24 months of first-line treatment (POD24), and four (6%) received prior chimeric antigen receptor T-cell (CAR-T) therapy. Overall response rate (ORR) and CR rate were 68% and 50%, respectively. In high-risk pts, consistent CR rates were observed: 55% (18/33) in pts with double refractory disease, 53% (16/30) in pts who had POD24, 78% (7/9) in pts with PI3Ki refractory FL, and 50% (2/4) in those who received prior CAR-T therapy. Twenty-six pts with a CR (74%) remained in remission (median time on study: 14.4 months). In responders (n=42), median duration of response was 20.4 months (95% CI: 11.7-not reached), and median progression-free survival was 11.8 months (95% CI: 7.3-21.9). Adverse events (AEs) and serious AEs were reported in 60 (97%) and 22 pts (35%), respectively. The most common grade (Gr) >=3 AEs included hypophosphatemia (23%) and neutropenia (21%). Fourteen pts (23%) experienced CRS1; events were mostly Gr 1 or 2, reversible, and occurred largely during C1.
Conclusion(s): A high CR rate, durable responses, and a manageable safety profile were observed with mosunetuzumab monotherapy in heavily pre-treated pts with FL, including high-risk pts.
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Context: Mosunetuzumab (Mosun), a full-length, humanized, IgG1 CD20xCD3 bispecific antibody, showed promising efficacy/safety for R/R B-NHL (NCT02500407; Assouline, et al. ASH 2020). Mosun combined with the anti-CD79b antibody-drug conjugate Pola showed synergistic anti-lymphoma activity in a mouse xenograft model, supporting the Phase Ib/II, open-label, multicenter trial of Mosun-Pola for R/R B-NHL (GO40516, NCT03671018).
Objective(s): To present early clinical data from the Phase Ib cohort of GO40516.
Method(s): Patients with R/R follicular lymphoma (FL, grade 1-3a) or aggressive NHL (aNHL), including de novo diffuse large B-cell lymphoma (DLBCL), transformed FL (trFL), and grade 3b FL (FL3b), received Cycle (C)1 step-up doses of Mosun on Day (D)1 (1 mg) and D8 (2 mg), and target dose on C1D15, continuing from C2D1. Mosun was given every 21 days for eight cycles, continuing for <=17 cycles. Pola (1.8 mg/kg) was administered with Mosun on D1 of six cycles.
Result(s): As of November 17, 2020, 22 patients received Mosun-Pola (Mosun target doses: 9 mg, n=7; 20 mg, n=3; 40 mg, n=6; 60 mg [D1 dose 30 mg from C3 onward], n=6). Patients had DLBCL (n=12), FL (n=3), FL3b (n=3), and trFL (n=4). Median age: 70 (38-81) years; median 3 (1-10) prior lines of therapy; prior chimeric antigen receptor T-cell (CAR-T) therapy (n=7; 32%). Median follow-up duration: 9.6 (0.7-23.7) months. Most frequent treatment-related adverse events (AEs): neutropenia (45.4%), fatigue, nausea, and diarrhea (all 36.4%). Cytokine release syndrome was observed in two patients (9.1%; both grade 1 [Lee, et al. Biol Blood Marrow Transplant 2019]). One dose-limiting toxicity (grade 3 new-onset atrial fibrillation) was observed in the 40 mg cohort; maximum tolerated dose not exceeded. Most common grade >=3 AE: neutropenia (n=8; 36.4%). Two (9.3%) grade 5 AEs occurred (sudden cardiac death [n=1]); respiratory failure [n=1]); neither was deemed treatment-related. Complete responses were achieved with Mosun-Pola in patients with R/R aNHL (n=9; 47.4%), prior CAR-T therapy (n=2; 28.6%) and FL (n=3; 100%).
Conclusion(s): These data indicate that Mosun-Pola has an acceptable safety profile and shows promising efficacy in patients with predominantly aggressive R/R NHL. The Phase II expansion cohort in patients with R/R DLBCL is ongoing, with no requirement for mandatory hospitalization.
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Antibody responses serve as the primary protection against SARS-CoV-2 infection through neutralization of viral entry into cells. We have developed a two-dimensional multiplex bead binding assay (2D-MBBA) that quantifies multiple antibody isotypes against multiple antigens from a single measurement. Here, we applied our assay to profile IgG, IgM and IgA levels against the spike antigen, its receptor-binding domain and natural and designed mutants. Machine learning algorithms trained on the 2D-MBBA data substantially improve the prediction of neutralization capacity against the authentic SARS-CoV-2 virus of serum samples of convalescent patients. The algorithms also helped identify a set of antibody isotypeâ€"antigen datasets that contributed to the prediction, which included those targeting regions outside the receptor-binding interface of the spike protein. We applied the assay to profile samples from vaccinated, immune-compromised patients, which revealed differences in the antibody profiles between convalescent and vaccinated samples. Our approach can rapidly provide deep antibody profiles and neutralization prediction from essentially a drop of blood without the need of BSL-3 access and provides insights into the nature of neutralizing antibodies. It may be further developed for evaluating neutralizing capacity for new variants and future pathogens.

Data addressing prognostication in patients with HIV related Burkitt lymphoma (HIV-BL) currently treated remain scarce. We present an international analysis of 249 (United States: 140; United Kingdom: 109) patients with HIV-BL treated from 2008 to 2019 aiming to identify prognostic factors and outcomes. With a median follow up of 4.5 years, the 3-year progression-free survival (PFS) and overall survival (OS) were 61% (95% confidence interval [CI] 55% to 67%) and 66% (95%CI 59% to 71%), respectively, with similar results in both countries. Patients with baseline central nervous system (CNS) involvement had shorter 3-year PFS (36%) compared to patients without CNS involvement (69%; P < .001) independent of frontline treatment. The incidence of CNS recurrence at 3 years across all treatments was 11% with a higher incidence observed after dose-adjusted infusional etoposide, doxorubicin, vincristine, prednisone, cyclophosphamide (DA-EPOCH) (subdistribution hazard ratio: 2.52; P = .03 vs other regimens) without difference by CD4 count 100/mm3. In multivariate models, factors independently associated with inferior PFS were Eastern Cooperative Oncology Group (ECOG) performance status 2-4 (hazard ratio [HR] 1.87; P = .007), baseline CNS involvement (HR 1.70; P = .023), lactate dehydrogenase >5 upper limit of normal (HR 2.09; P < .001); and >1 extranodal sites (HR 1.58; P = .043). The same variables were significant in multivariate models for OS. Adjusting for these prognostic factors, treatment with cyclophosphamide, vincristine, doxorubicin, and high-dose methotrexate, ifosfamide, etoposide, and high-dose cytarabine (CODOX-M/IVAC) was associated with longer PFS (adjusted HR [aHR] 0.45; P = .005) and OS (aHR 0.44; P = .007). Remarkably, HIV features no longer influence prognosis in contemporaneously treated HIV-BL.

Central nervous system (CNS) involvement in Burkitt lymphoma (BL) poses a major therapeutic challenge, and the relative ability of contemporary regimens to treat CNS involvement remains uncertain. We described prognostic significance of CNS involvement and incidence of CNS recurrence/progression after contemporary immunochemotherapy using real-world clinicopathologic data on adults with BL diagnosed between 2009 and 2018 across 30 US institutions. We examined associations between baseline CNS involvement, patient characteristics, complete response (CR) rates, and survival. We also examined risk factors for CNS recurrence. Nineteen percent (120/641) of patients (age 18-88 years) had CNS involvement. It was independently associated with HIV infection, poor performance status, involvement of ≥2 extranodal sites, or bone marrow involvement. First-line regimen selection was unaffected by CNS involvement (P=0.93). Patients with CNS disease had significantly lower rates of CR (59% versus 77% without; P<0.001), worse 3-year progression-free survival (adjusted hazard ratio [aHR], 1.53, 95% confidence interval [CI], 1.14-2.06, P=0.004) and overall survival (aHR, 1.62, 95%CI, 1.18-2.22, P=0.003). The 3-year cumulative incidence of CNS recurrence was 6% (95%CI, 4-8%). It was significantly lower among patients receiving other regimens (CODOX-M/IVAC, 4%, or hyperCVAD/MA, 3%) compared with DA-EPOCH-R (13%; adjusted sub-HR, 4.38, 95%CI, 2.16-8.87, P<0.001). Baseline CNS involvement in BL is relatively common and portends inferior prognosis independent of first-line regimen selection. In real-world practice, regimens with highly CNS-penetrant intravenous systemic agents were associated with a lower risk of CNS recurrence. This finding may be influenced by observed suboptimal adherence to the strict CNS staging and intrathecal therapy procedures incorporated in DA-EPOCH-R.