Refractory B-cell non-Hodgkin Lymphoma Research Articles

Long-term Remissions Following CD20-directed Chimeric Antigen Receptor Adoptive T cell Therapy.

Chimeric antigen receptor (CAR) T cell therapy produces high response rates in refractory B-cell non-Hodgkin lymphoma (NHL), but long-term data are minimal to date. Here, we present long-term follow-up of a pilot trial testing a CD20-targeting 3rd generation CAR in patients with relapsed B-cell lymphomas following cyclophosphamide-only lymphodepletion. Two of the 3 patients in the trial, with mantle cell lymphoma and follicular lymphoma, had remissions lasting more than 7 years, though they ultimately relapsed. The absence of B cell aplasia in both patients suggested a lack of functional CAR T cell persistence, leading to the hypothesis that endogenous immune responses were responsible for these long remissions. Correlative immunologic analyses supported this hypothesis, with evidence of new humoral and cellular anti-tumor immune responses proximal to clinical response time points. Collectively, our results suggest that CAR T cell therapy may facilitate epitope spreading and endogenous immune response formation in lymphomas.

Abstract CT037: A phase I investigator-initiated trial of evorpacept (ALX148), lenalidomide and rituximab for patients with relapsed or refractory B-cell non-Hodgkin lymphoma

Abstract Introduction. We have recently demonstrated that pro-tumoral SIRPα+ macrophages may mediate resistance to lenalidomide and rituximab (R2) in patients (pts) with relapsed or refractory (RR) B-cell non-Hodgkin lymphoma (B-NHL). Evorpacept (ALX148) is a novel high-affinity CD47 blocker that abrogates the ‘do-not-eat-me signal’ provided to SIRPα+ macrophages. In a phase I trial including 33 pts with RR B-NHL it was well tolerated in combination with rituximab. We hypothesized that evorpacept and R2 will be synergistic, and the combination will be safe and effective for the treatment of pts with RR B-NHL. Methods. This single arm phase I study (NCT05025800) was conducted between 11/2021 and 9/2023 (data cut-off 12/2023). Adult pts with RR B-NHL who had received at least 2 prior lines of systemic therapy (1 in case of indolent B-NHL [iNHL]) were included. Evorpacept was administered intravenously (IV), in a 28-day cycle, for 12 cycles, at two dose levels (DL): 30 mg/Kg on day (D) 1 and D15 (DL1), or 60 mg/Kg on day 1 (DL2); rituximab IV was given weekly during cycle 1, and on D1 during cycles 2-6; lenalidomide was given orally on D1-21 during cycles 1-6. Dose limiting toxicity (DLT) was evaluated according to CTCAE v5 during cycle 1 and a Bayesian Optimal Interval design was used, with a target DLT rate of 0.3. Response was assessed according to Lugano 2014 criteria. Results. Twenty pts were included in the study. Median age was 61 (27-85), 10 (50%) were male, and 7 (35%) were non-white; 15 (75%) had follicular lymphoma, 3 (15%) marginal zone lymphoma, 1 (5%) mantle cell lymphoma, and 1 (5%) Richter Syndrome; 20 (100%) had previously received an anti-CD20 monoclonal antibody, 13 (72%) chemoimmunotherapy, and 15/18 (83%) iNHL pts had intermediate-high FLIPI. Three pts were treated at DL1, 17 at DL2, and no DLT was observed. The most common grade 3-4 adverse events included: neutropenia (55%), infections (30%), ALT increase (15%), AST increase (10%), skin rash (10%), and anemia (10%). Eight (40%) pts experienced a cycle delay, mainly due to grade (G) 1 AST/ALT elevation; 6 (30%) required a dose reduction for lenalidomide, none for evorpacept; 1 pt discontinued treatment after 1 cycle due to G3 lenalidomide-associated myocarditis. Sixteen (80%) pts achieved CR and best overall response rate was 90%. After a median follow-up of 16 months (95% CI, 12-20 months), 1-year PFS rate was 70% and 1-year OS rate was 90%. Conclusions. The combination of evorpacept and R2 is well tolerated in pts with RR B-NHL, with similar toxicity and promising anti-tumoral activity as compared to historical CR rates with R2 alone (34%). Bulk RNA sequencing and multiplex immunofluorescence are being performed on tissue biopsies collected before and during treatment, to characterize its effects on the tumor immune microenvironment. A phase 2 study investigating its efficacy in pts with previously untreated iNHL is now enrolling. Citation Format: Paolo Strati, Lei Feng, Dai Chihara, Jason Westin, Sairah Ahmed, Luis Fayad, Jared Henderson, Jeffrey Davidson, Elizabeth McChesney, Loretta Nastoupil, Sattva Neelapu, Christopher Flowers. A phase I investigator-initiated trial of evorpacept (ALX148), lenalidomide and rituximab for patients with relapsed or refractory B-cell non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT037.

Abstract CT173: Preliminary results from a phase I study of IMM0306 in patients with relapsed or refractory CD20-positive B-cell non-Hodgkin's lymphoma

Abstract Background: IMM0306 is a fusion protein of CD20 monoclonal antibody with the CD47 binding domain of SIRPα on both heavy chains. It exerts excellent cancer killing efficacy by activating both macrophages and NK cells via blockade of CD47-SIRPα interaction and FcɣR engagement. Here, we report the safety, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy results of phase I in patients (pts) with relapsed or refractory (R/R) CD20-positive B-cell non-Hodgkin's lymphoma (B-NHL). Methods: Eligible pts with R/R CD20-positive B-NHL were enrolled in this open-label, multicenter phase I/II study (NCT05805943). IMM0306 was administered as monotherapy at escalating doses of 0.04, 0.1, 0.25, 0.5, 0.8, 1.2, 1.6, 2.0 mg/kg intravenously once a week after a 2-week single-dose observation period, until disease progression or intolerable toxicity. Dose-limiting toxicity (DLT) was evaluated in the first 28 days. Safety was evaluated per CTCAE 5.0, PK and PD analysis were also assessed, tumor assessments performed once every 8 weeks by Lugano 2014. Results: As of Nov 21, 2023, 48 pts were enrolled. The median age was 56 years with 30 (62.5%) males. The median prior lines of therapy was 2. All pts received previous anti-CD20 therapy. No DLTs were observed. Recommended phase II dose (RP2D) was determined as 2.0 mg/kg. The most frequent treatment related adverse events (TRAEs) were WBC decreased (66.7%), anemia (64.6%), lymphocyte decreased (58.3%), ANC decreased (47.9%), PLT decreased (45.8%), infusion-related reactions (35.4%). Grade ≥3 TRAEs occurred in 33 (68.8%) pts, the most frequent grade ≥ 3 TRAEs were lymphocyte decreased (56.3%), WBC decreased (18.8%), ANC decreased (18.8%). Eight (16.7%) pts experienced treatment related serious adverse event, including PLT decreased, chest pain and pneumonia. Drug discontinuation due to AEs occurred in 1 pt (G4 PLT decreased occurred at 1.6mg/kg without any bleeding). No AE led to death. IMM0306 exhibited approximate dose-proportional increase in PK exposure from 0.5 to 2.0 mg/kg and no obvious accumulation was observed after repeated dosing. At 1.2 mg/kg, CD47 receptor occupancy on peripheral lymphocytes was saturated, suggesting IMM0306 is well tolerated from perspective of CD47 engagement in high dose cohorts. B-cell counts depleted rapidly at doses ≥ 0.8 mg/kg. Elevated cytokines levels were observed after first dosing of IMM0306, but multiple dosing did not stimulate further cytokine activation. Among 33 pts who received active doses ≥ 0.8 mg/kg, 5 CR (4 follicular lymphoma [FL], 1 marginal zone lymphoma [MZL]), 5 PR (3 FL, 1 MZL, 1 diffuse large B cell lymphoma) and 11 SD were seen. Among 17 FL pts, 7 (41%) responded including 4 CR and 3 PR; among 6 MZL pts, 2 (33.3%) responded including 1 CR and 1 PR. Conclusions: IMM0306 was well-tolerated and with a robust preliminary anti-tumor activity especially in pts with R/R FL and MZL. The phase II study is ongoing. Citation Format: Yuankai Shi, Jianliang Yang, Yongping Song, Keshu Zhou, Zhiming Li, Mingzhi Zhang, Hongmei Jing, Zhen Wang, Li Yu, Qiying Lu, Frank Gan, Wenzhi Tian. Preliminary results from a phase I study of IMM0306 in patients with relapsed or refractory CD20-positive B-cell non-Hodgkin's lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT173.

A Global Study of Novel Agents in Paediatric and Adolescent Relapsed and Refractory B-Cell Non-Hodgkin Lymphoma (Glo-BNHL)

Overview Glo-BNHL is an adaptive prospective international academic-led multicentre platform clinical trial designed to evaluate the efficacy and safety of the most promising novel agents as monotherapy or in combination with existing therapies for the treatment of children, adolescents, and young adults with relapsed or refractory (r/r) B-cell Non-Hodgkin Lymphoma (B-NHL). A direct output of the second ACCELERATE multi-stakeholder Paediatric Strategy Forum (Pearson, 2019), Glo-BNHL was designed in collaboration with patient advocates, is supported by the Regulatory Authorities, and the intent is for trial data to support filing for marketing authorisation. Rationale Outcomes for r/r paediatric B-NHL are extremely poor with long term cure rates lower than 30%. Glo-BNHL fulfils the critical need for a single collaborative global approach to find new treatments for these rare patients for whom current therapy is inadequate. It allows for a rational approach to investigating the array of potentially promising agents currently in development for adults. The classes of agents currently prioritised for inclusion in Glo-BNHL are: Treatment Arm I: bispecific antibodies (BsAbs)Treatment Arm II: antibody-drug conjugates (ADCs) combined with standard chemotherapyTreatment Arm III: chimeric antigen receptor (CAR) T-cell products A robust systematic assessment of each asset is undertaken before a decision to include in the platform is made (published separately). Population Glo-BNHL will enrol participants in ≥45 sites in 18 countries spanning Europe, Asia, North America and Australasia. Eligible patients are aged ≤25 years with radiologically or histologically proven relapsed (≥ first) or refractory B-NHL with evaluable disease, adequate organ function, negative pregnancy test, agreement to use effective contraception and written informed consent. Key exclusion criteria include recent stem cell transplant, craniospinal radiation or investigational treatment, on-going moderate or severe acute toxicities, uncontrolled infection or primary immunodeficiency. Patients may be enrolled into any of the available treatment arms for which they are eligible. Statistical Design In this rare population we anticipate global enrolment of 30 patients per year. The Bayesian design enables initial cohorts of 15 patients to be meaningfully evaluated. A transition analysis will estimate with ≥80% certainty whether the true efficacy of the treatment exceeds the pre-defined target response rate. Agents demonstrating sufficient promise will be further evaluated in an expansion stage, following discussion with regulators to clarify data requirements to enable subsequent approval of the agent. Confirmatory analyses of all evaluable patients will estimate with ≥95% certainty whether the true efficacy exceeds the target response rate (“GO”). During both initial and expansion stages patients will be closely monitored, with regular interim futility analyses employed, allowing a treatment arm to stop early if there is very little probability of efficacy (“NoGO”). Outcome measures Primary outcomes measures are occurrence of an objective response after 12 weeks of treatment (Treatment Arm I), occurrence of complete response within a maximum of three cycles of treatment (Treatment Arm II) and occurrence of an objective response following CAR T-cell infusion (Treatment Arm III). Secondary outcome measures include event-free survival, progression-free survival, overall survival time, best overall response, duration of response, adverse events, pharmacokinetic profile and pharmacodynamics markers. Treatment Treatment Arm I: Odronextamab (Regeneron) - a human CD20xCD3 bispecific antibody - monotherapy will be given as an intravenous infusion weekly for 12 weeks, then at a decreasing frequency until progression or up to two years for responding patients. Treatment Arm II: Loncastuximab tesirine (ADC Therapeutics) - a humanised CD19-targeting monoclonal antibody with PBD dimer cytotoxin - will be given as an intravenous infusion with each cycle of modified R-ICE chemotherapy (rituximab, ifosfamide, carboplatin, etoposide and dexamethasone) for up to three cycles. Treatment Arm III: product negotiations are on-going Conclusion Glo-BNHL addresses an urgent unmet clinical need through an innovative trial design serving as a paradigm for evaluation of novel agents in very rare diseases.

A First-in-Human Phase 1 Study of ABBV-525, a Small-Molecule MALT1 Inhibitor, in Patients with Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma

Background and Significance Many B-cell malignancies are characterized by chronic activation of the B-cell receptor (BCR) and nuclear factor kappa B (NF-κB) signaling pathways. In many non-Hodgkin lymphoma (NHL) subtypes, constitutive NF-κB activation results from genetic mutations and/or auto-antigen stimulation of the BCR pathway. While agents targeting the BCR pathway are effective treatments for many B-cell malignancies, patients (pts) often have progressive disease due to acquired resistance to BCR-targeted agents. Thus, there is an unmet medical need for novel therapeutic targets and treatment approaches. The mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) is an enzymatic and scaffolding node in the BCR pathway and a key mediator of the BCR/NF-κB signal transduction pathway. Its action is downstream, or in some instances parallel to, resistance mechanisms to existing NHL therapies, including BTK C481S and PLCG2 mutations, which are known acquired mechanisms of resistance to covalent Bruton's tyrosine kinase (BTK) inhibitors in pts with chronic lymphocytic leukemia (CLL). MALT1 inhibition represents a novel therapeutic approach for malignancies with chronic activation of NF-κB, including those pts with acquired resistance to upstream targets. ABBV-MALT1 is a small-molecule, tool compound, MALT1 inhibitor. Preclinical studies of ABBV-MALT1 have demonstrated potent activity against MALT1-relevant biomarkers, including inhibition of BCR pathway signal transduction and reduced NF-κB gene activation in non-germinal center B-cell diffuse large B-cell lymphoma (non-GCB DLBCL) cell lines. ABBV-MALT1 has also shown activity in a range of preclinical lymphoma models as both monotherapy and in combination with venetoclax, including robust antitumor activity in malignant B-cell models that are resistant to BTK inhibitors. This phase 1 study evaluates the clinical candidate MALT1 inhibitor ABBV-525 as monotherapy in pts with relapsed or refractory (R/R) B-cell NHL. Study Design and Methods This is a first-in-human, phase 1, open-label, multicenter study of single-agent ABBV-525 in pts with R/R B-cell NHL (NCT05618028). Eligibility criteria are listed in Table 1. The primary objectives are to evaluate safety, tolerability, and pharmacokinetics (PK) of ABBV-525 and to determine the recommended phase 2 dose (RP2D). The secondary objective is to assess the preliminary efficacy of ABBV-525 in subsets of pts with R/R B-cell NHL. Exploratory objectives include evaluating biomarkers predictive of response and pharmacodynamic biomarkers, including the effects of ABBV-525 on BCR pathway signal transduction and NF-κB gene activation. This is a 3-part study (Figure 1): dose escalation (part 1), dose optimization (part 2), and dose expansion (part 3). Part 1 aims to establish the maximum administered dose/maximum tolerated dose of ABBV-525 and is primarily guided by a Bayesian optimal interval design. Part 2 aims to identify the RP2D of ABBV-525. Part 3 will further characterize the safety profile of ABBV-525 at the RP2D. Approximately 150 pts are planned for enrollment, including those with various R/R mature B-cell lymphomas in part 1, pts with documented diagnosis of R/R CLL in part 2, and pts with documented diagnosis of non-GCB DLBCL in part 3. ABBV-525 is orally administered until disease progression, intolerable toxicity, or other study discontinuation criteria are met. Safety assessments include dose-limiting toxicities, adverse events (per National Cancer Institute Common Terminology Criteria for Adverse Events v5.0), clinical laboratory parameters, vital signs, and electrocardiogram variables. PK parameters, including maximum observed plasma concentration (C max), time to C max, and area under the concentration-time curve will be analyzed using noncompartmental methods. Efficacy will be assessed through response per disease-specific criteria (including International Workshop on Chronic Lymphocytic Leukemia, International Workshop on Waldenstrom's Macroglobulinemia, and Lugano classification). Duration of response will be evaluated by Kaplan-Meier estimates. Biomarker data will be analyzed as change from baseline and summarized for each scheduled postbaseline visit. Pts are being enrolled in 25 sites across the USA, Australia, Belgium, France, Germany, Israel, Spain, and UK. As of August 1, 2023, 2 pts had been treated.

Efficacy and Safety of CD19-Specific CAR-T Cell Therapy Following Immunochemotherapy in Newly Diagnosed B-Cell Lymphoma Associated Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) represents a grave and potentially fatal systemic inflammatory condition. Lymphoma associated hemophagocytic lymphohistiocytosis (LAHS), as a common type in secondary HLH, suffers the worst outcome among sHLH. B cell Lymphoma associated hemophagocytic lymphohistiocytosis (B-LAHS) typically presents as high-risk lymphoma and is associated with a poorer prognosis compared to B cell lymphoma without HLH with standard first-line chemoimmunotherapy. As a result, there is an urgent need for more effective therapeutic strategies. Recent advancements in chimeric antigen receptor (CAR) T-cell therapy have demonstrated remarkable responses in relapsed or refractory B-cell non-Hodgkin lymphoma (B-NHL), as well as in some high-risk newly diagnosed B-cell lymphoma. However, There have been no clinical reports regarding the application of CAR-T cell treatment as part of first-line therapy in B-LAHS. We assessed the effectiveness and safety of autologous anti-CD19 CAR-T cell therapy following an immunochemotherapeutic regimen based on R-DEP (Rituximab-doxorubicin-etoposide-methylprednisolone) as a first-line treatment option for patients with B-LAHS. As of 1 July 2023, a cohort of 13 patients diagnosed with B-LAHS（with 3 cases enrolled before registration for clinical trials）was recruited for evaluation and met the criteria for assessing treatment efficacy at our institution. The overall response rate (ORR) for HLH was 100% (with 7 cases achieving complete response and 6 cases achieving partial response) prior to infuse CAR-T cells and the ORR for lymphoma also was 100% (with 10 cases achieving complete response and 3 cases achieving partial response) on the time of a month after CAR-T cell infusion. As of the follow-up date on 1 July 2023 (with a median follow-up time of 14 months), all 13 patients were still alive, 12 cases maintained sustained remission, while 1 case experienced relapse at 16 months after CAR-T cell infusion. The median overall survival (OS) has not been reached, and the median progression-free survival (PFS) was 31.5 months. To provide comparison, we included a group of 26 patients diagnosed with B-LAHS who did not receive CAR-T cell therapy during the same period. The non-CAR-T group demonstrated a significantly lower median OS of 5.93 months and a median PFS of 4.43 months, highlighting the superior prognosis of the CAR-T group (p < 0.001). Regarding adverse events, the CAR-T group exhibited a cytokine release syndrome (CRS) incidence of 53.8% (7/13) and an immune effector cell-associated neurotoxicity syndrome (ICANS) incidence of 30.7% (4 /13), all of which were classified as grade 1. None of the patients experienced non-hematologic toxicity of grade ≥3. While all 13 patients developed cytopenias, hematologic toxicity reactions ≥ grade 3 were observed in 76.9% (10 /13) of patients, but blood cell counts recovered within 3 weeks. Robust expansion of CAR T-cells occurred in all patients, with a median time to peak expansion of 8 days. Importantly, no exacerbation of hemophagocytic syndrome occurred following CAR-T cell infusion, and no patients succumbed to adverse events. In conclusion, our findings suggest that CD19 CAR-T cell treatment exhibits high efficacy as part of first-line therapy for B-LAHS, with a manageable safety profile.

A Phase 1 Dose Escalation Trial of Third-Generation CD19-Directed CAR T-Cells Incorporating CD28 and Toll-like Receptor 2 (TLR2) Intracellular Domains for Relapsed or Refractory B-Cell Non-Hodgkin Lymphomas (ENABLE)

Introduction: Chimeric antigen receptor (CAR) T cell therapies directed against CD19 and incorporating either CD28 or 4-1BB intracellular co-stimulatory domains are a standard of care for relapsed or refractory (r/r) B-cell lymphomas. CD19-directed CAR T-cell products employing CD28 co-stimulation yield high response rates, but have been associated with higher rates of immune effector cell-associated neurotoxicity syndrome (ICANS) and severe cytokine release syndrome (CRS) than 4-1BB co-stimulated products. There is a need for CAR T-cell products that combine high efficacy with low toxicity. Toll-like receptor 2 (TLR2) is expressed by T-cells, and its engagement enhances T-cell expansion, modulates cytokine production, and promotes long-lived T-cell memory. In preclinical studies, interposition of an intracellular domain from TLR2 between CD28 and CD3ζ resulted in reduced CAR T-cell production of ICANS-associated cytokines GM-CSF and IFN-γ, while maintaining production of the homeostatic cytokine IL-7. We investigated the safety and efficacy of a novel third generation CD19-directed CAR T-cell product, which combines CD28 and TLR2 co-stimulatory domains ( Figure). Methods: We completed a first-in-human phase 1 dose escalation trial of WZTL-002, comprising autologous 1928T2z CAR T-cells (‘ENABLE’, NCT04049513) for patients with r/r B-cell non-Hodgkin lymphomas (B-NHL). A 3+3 dose escalation design was used, with doses from 5 × 10 4 to 1 × 10 6 viable CAR T-cells/kg body weight. Eligible participants had radiologically assessable disease, satisfactory organ function and no central nervous system (CNS) involvement by lymphoma. Bridging therapy was permitted after leukapheresis and pending CAR T-cell manufacture and release. WZTL-002 CAR T-cells were administered intravenously after 3 days of fludarabine (30mg/m 2/day) and cyclophosphamide (500mg/m 2/day) lymphodepletion. Adverse events (AEs) were graded by CTCAE 5.0 except CRS and ICANS (graded by American Society for Transplantation and Cellular Therapy criteria). Response assessment was by PET/CT at month 3, per Lugano 2014 criteria. Pharmacokinetic analyses were by droplet digital PCR for CAR transgenes in blood mononuclear cells. Results: Of 21 patients treated within the dose escalation trial, median age was 57 years (range 23 - 70); 10 (48%) were female; 4 (19%) Māori. Lymphomas were of large cell histology in 17 (81%, Table). Participants had received a median of 4 prior lines of therapy, including autograft in 11 (52%) and allograft in 1. Product phenotyping showed WZTL-002 CAR T-cells were median 49% CD4 +, 41% CD8 + and 34% CD62L +. As of June 14 2023, all patients had reached the primary follow-up timepoint (3 months after WZTL-002 administration). Grade ≥ 3 AEs occurring in ≥ 10% of recipients were: neutropenia (95%), lymphopenia (57%), hypogammaglobulinemia (57%), anaemia (43%), febrile neutropenia (43%), thrombocytopenia (24%) and tumor pain (19%). Grade 1 - 2 CRS occurred in 13 patients (62%); 6 received tocilizumab and 3 dexamethasone. No CRS of grade ≥ 3, and no ICANS of any grade, occurred. Two grade 4 cytopenia dose limiting toxicities occurred at day 21 (one each at 5 × 10 5 and 1 × 10 6 cells/kg), both resolved to grade 2 by day 90. Maximum tolerated dose was not reached. Responses were seen at all dose levels with complete metabolic response in 11 (52%) at month 3. WZTL-002 CAR T-cells expanded at all dose levels. Among recipients of 0.5 - 1.0 × 10 6 CAR T-cells/kg (n = 12), median peak CAR T-cell level (C max) was 93,950 transgene copies/μg genomic DNA (reached at median day 10) and CAR T-cells persisted in 9 of 11 assessed (82%) at day 90. A recommended phase 2 dose (RP2D) range of 0.5 - 1 × 10 6/kg was selected. Conclusions: In this dose escalation trial of a novel third-generation CD19-directed CAR T-cell product that combines CD28 and TLR2 co-stimulatory domains for r/r B-NHL, we observed no severe CRS, no ICANS of any grade and complete responses at all dose levels. At RP2D, in vivo CAR T-cell expansion was similar to or greater than other CD19-directed products. In conjunction with preclinical findings, this study suggests interposition of a TLR2 domain between CD28 and CD3ζ domains may reduce CAR T-cell-related ICANS risk while retaining efficacy. Enrolment to a dose expansion cohort has commenced and will assess outpatient management and the safety and efficacy of WZTL-002 CAR T-cells manufactured using a closed automated process.

Safety and Efficacy of a-319 (a CD3xCD19 T cell engager) in Patients with Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma

Background: A-319 is a CD19 x CD3 bispecific T cell engager to treat B-cell non-Hodgkin Lymphoma (B-NHL). A-319 contains a scFV domain derived from SP34 CD3 antibody and a CD19 binding domain in a Fab format without Fc. A-319 has the same mechanism of action as that of blinatumomab, and may benefit B-NHL patients. We report the phase I study results of A-319 in patients with relapsed/refractory B-NHL. Methods: The current study is a multi-center, open-label, dose-escalation phase I clinical study. The primary endpoint was to determine the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of A-319. The secondary endpoints were to evaluate the pharmacokinetics (PK) and efficacy. During dose escalation stage, one treatment cycle contains one week of A-319 priming doses and three weeks of treatment doses. During priming doses, A-319 was administered three times per week (day 1, day 3 and day 5) at dose level of 0.05 ug/kg/day by 24 hr IV infusion. Dose escalation started at week two at dose level of 0.05, 0.15, 0.3, 0.6, 1.2, 1.8 and 2.4 ug/kg/day, respectively, by 6 hr IV infusion three times per week. The study was registered at ClinicalTrials.gov (NCT04056975). Results: A total of 21 B-NHL patients (CD19+) were treated with A-319 for at least 1 cycle. Eighteen (85.7%) patients experienced adverse events and 12 (57.1%) patients experienced treatment-related adverse events (TRAEs). The most common TRAE was cytokine release syndrome (CRS, 23.8%, n=5), followed by fever (66.7%, n=14) and decreased immunoglobulin (23.8%, n=5). Most of the reported adverse events were CTCAE Grade I-II. Five patients experienced CRS (Grade I-II, n=5；≥Grade III, n=0). Six patients experienced immune effector cell-associated neurotoxicity syndrome (Grade I-II, n=6；Grade III, n=2). The serious adverse events were reported in 3 patients, which included lung infection (Grade III, n=1), interstitial pneumonia (Grade I, n=1), and pulmonary embolism (Grade III, n=1). There was no reported DLT. No fatal cases were reported during treatment. The preliminary pharmacokinetic (PK) results showed that A-319 has linear PK properties with an estimated T 1/2 of 6-10 hrs. Preliminary responses were reported that one patient achieved complete remission (CR), 3 achieved partial remission (PR), and 7 achieved stable disease (SD) after one cycle of treatment. In the 5 th cohort (at the dose level of 1.2 ug/kg/day), one patient with diffuse large B cell lymphoma (DLBCL) achieved CR, one with follicular lymphoma (FL) achieved PR and on with DLBCL achieved SD. Conclusions: A-319 was well tolerated in relapsed/refractory B-NHL. A-319 at the dose level of 1.2 ug/kg/day showed encouraging disease control and warranted further clinical investigation.

Establishment of a Dynamic Ctdna Monitoring System to Predict the Prognosis of CAR-T Cell Therapy in R/R B-NHL Patients

Introduction: The objective of this study is to establish a prediction system using circulating tumor DNA (ctDNA) to determine the effectiveness of CAR-T cell therapy in patients with relapsed or refractory B-cell non-Hodgkin lymphoma (R/R B-NHL). Furthermore, the study aims to compare the mutation characteristics between different therapeutic groups to provide guidance for the prevention and follow-up treatment of patients who fail CAR-T cell therapy. Methods: In this part of the study, a total of 79 (192 serum samples) R/R B-NHL patients with CAR-T cell therapy were collected for ctDNA detection (187 lymphoma-related gene panel), including 62 samples before treatment (T0), 69 samples at 1 week (T1) and 62 samples at 4 weeks (T2) after reinfusion. Differences of categorical variables were tested using the chi-square test or Fisher's exact test, and differences in survival events between different groups were compared using Kaplan-Meier analysis and log-rank test. Results: The results of Kaplan-Meier analysis showed that patients with ctDNA mutation genes >10 before CAR-T cell therapy had poorer OS (1-year OS rate: 0% vs 74.9%, 2-year OS rate: 0% vs 68%, P<0.001) and PFS (1-year PFS rate: 0% vs 52.5%, 2-year PFS rate: 0% vs 36.6%, P=0.0056). Patients with MYD88, FAT1 and BTG2 mutation before CAR-T cell therapy had poorer OS, while patients with MUC16 mutation had better OS. The CR rate in patients with TP53 mutation before CAR-T cell treatment was significantly lower than that of patients without TP53 mutation (33.3% vs 68.1%, P=0.02). However, the TP53 mutation status before treatment did not have an impact on the long-term survival of patients. All patients with TP53 mutations at 4 weeks after CAR-T cell therapy failed to achieve CR, and OS was poorer (1-year OS rate: 37.5% vs 66.4%; 2-year OS rate: 12.5% vs 56.3%, P=0.0023). For CR patients, patients with BCR mutation at 4 weeks after treatment had poorer OS (2-year OS rate: 40.9% vs 76.1%, P=0.035). At one week after CAR-T cell therapy(Figure 1), patients without mutations of CDKN2A, CBLB, APC, SPEN, KMT2D, CARD11, FOXO1 and PDGFRB, were more likely to achieve CR (76.6% vs 28.6%, P<0.001), and had better OS (1-year OS rate: 81.5% vs 38.9%, 2-year OS rate: 62.2% vs 5%, P<0.001) and PFS (1-year PFS rate: 67.2% vs 0%, P<0.001). Conclusions: In this study, we evaluated the characteristics of gene mutation between different therapeutic groups, and a gene set was screened to predict the efficacy of CAR-T cell therapy in R/R B-NHL patients, helping clinicians accurately evaluate the efficacy and assisting in decision-making of treatment options.

GB261, an Fc-Function Enabled and CD3 Affinity De-Tuned CD20/CD3 Bispecific Antibody, Demonstrated a Highly Advantageous Safety/Efficacy Balance in an Ongoing First-in-Human Dose-Escalation Study in Patients with Relapsed/Refractory Non-Hodgkin Lymphoma

Introduction: GB261 is a novel and highly differentiated CD20/CD3 bispecific T cell engager antibody computationally designed to maintain Fc effector function, i.e., antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC) to broaden the mechanisms of action (MOA) for tumor cell killing. Furthermore, the “imbalanced” design of GB261 integrates de-tuned CD3 binding to reduce CRS incidence and improve safety features of the Fc effector function. Extensive pre-clinical studies have shown that GB261 has a highly advantageous safety/efficacy balance.Here, we present the preliminary clinical safety and efficacy results of an ongoing phase I/II study for GB261 (NCT04923048). Methods: This is an open-label, multicenter (China and Australia), dose-escalation/expansion phase 1/2 study of GB261 to evaluate the safety, tolerability and efficacy in patients with Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma(B-NHL) and Chronic Lymphocytic Leukemia (CLL). Adult patients were eligible when they have CD20+ r/r B-NHL or CLL with no available standard of care treatments, adequate organ function, and no CNS involvement or other CNS disease, infections or other active/serious medical issues that may affect compliance or interpretation of results. GB261 was administered in 21-day cycles, weekly (QW) for the first 6 doses followed by every 3 weeks (Q3W) until disease progression, or other situation defined in protocol. Response assessment was based on Lugano 2014 and LYRIC 2016 criteria. Results: As of June 17, 2023, 47 r/r B-NHL patients (DLBCL:76.6%; FL:23.4%) were enrolled at flat or step-up doses of GB261 ranging from 1mg to 300 mg. Median age was 60.0 years (range: 28, 81), 55.3% of patients were male. Median prior lines of therapy were 3 (range: 1, 10). 78.7% of patients were refractory to any anti-CD20 therapy, 70.2% refractory to their last systemic therapy. Median time since last prior therapy to first study treatment was 1.9 months. In efficacy evaluable patients (n=22) from 3mg to 100mg, with at least 75% dose exposure before the first radiographic assessment, the median duration of study follow-up was 4.5 months (95%CI: 4.0, 7.4). The overall response rate (ORR) was 73% (16/22), and complete response rate (CRR) was 45.5% (10/22). ORR and CRR were 100% and 100% in 3mg, 56% and 22% in 10mg, 67% and 33% in 30mg. At 100mg dose, there were 5 evaluable patients, with ORR 100% (5/5), CRR 80% (4/5) and PR (20%, 1/5; mosunetuzumab-refractory rrDLBCL patient). Median time to response (TTR) was 1.3 months (95%CI: 1.2, 1.5), the same as median time to CR. Median duration of response (DOR) was not reached. In safety evaluable patients (n=47), the median duration of study follow-up was 4.1 months (95%CI: 2.9, 5.3). Treatment-emergent adverse events (TEAEs) were 95.7%, treatment-related adverse events were 85.1%. The most common TEAEs were COVID-19 infection (40.4%; grade 1 or 2: 27.6%; grade >=3: 12.8%) and neutropenia (31.9%; grade 1or 2: 14.9%; grade >=3: 17.0%). AE related treatment discontinuation and death were reported in 2 patients, which were all due to COVID-19 pneumonia. CRS occurred in 12.8% (6/47) patients, was mild and transient. CRS in 100mg were 14.3% (2/14). All cases of CRS were grade 1 (8.5%, 4/47) or 2 (4.3%, 2/47), no grade 3 (Lee et al., ASTCT criteria), no interruptions of treatment, and no administration of Tocilizumab. The median duration of CRS was 7 hours. No ICANS were reported. The PK profile of GB261 appeared to be linear across dose ranges tested (1mg-100mg). Effective half-life appeared to be 2-3 weeks which supports every 3-4 weeks dosing. Conclusion: GB261, a novel and highly differentiated CD20/CD3 bispecific antibody, is the first clinical stage Fc+ CD20/CD3 T cell engager. In heavily pretreated B-NHL patients, GB261 showed a highly advantageous safety/efficacy balance, consistent with the MOA. The safety profile is excellent especially for the CRS which is very mild, transient and less frequent compare with other CD20/CD3 bispecific antibodies. The response after GB261 treatment was early, deep and durable. At the 100mg dose level, 80% of patients achieved CR and with favorable safety. Additionally, clinical benefit seen in other CD20/CD3 bispecific antibody failed patients provides clinical support to the unique and differentiated MOA of GB261.

A Phase 1 Cohort Dose Escalation and Expansion Trial to Determine the Safety, Tolerance, Maximum Tolerated Dose, and Preliminary Antineoplastic Activity of IKS03 in Patients with Advanced B-Cell Non-Hodgkin Lymphomas (NHL)

Background: IKS03 is an antibody-drug conjugate (ADC) comprising an anti-CD19 antibody conjugated with novel ConjuALL technology to a highly potent proprietary DNA-crosslinking pyrrolobenzodiazepine (PBD) prodrug payload for the treatment of CD19-positive hematologic malignancies. Both the payload and the linker of IKS03 incorporate an innovative tumor-selective chemistry that takes advantage of the overexpression of beta glucuronidase in cancer cells compared to most normal tissues. Payload release and activation require cleavage of glucuronide moieties that are incorporated into the linker payload structure providing improvements in both efficacy and safety compared to traditional ADC formats. This “glucuronide trigger” is stable while in circulation with minimal to no systemic payload release from the ADC. Following binding and internalization of IKS03 into a CD19-positive cancer cell, beta glucuronidase can release the active PBD payload leading to cell death. Normal tissues without CD19 expression and/or with low levels of the beta glucuronidase enzyme have limited ADC uptake, are less able to process IKS03 and are differentially spared. In preclinical studies, IKS03 demonstrated significant in vivo efficacy with complete tumor regressions in CD19-positive diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and mantle cell lymphoma (MCL) xenograft models at single doses of 0.1 to 1 mg/kg. IKS03 demonstrated greater activity than the clinical benchmark ADC loncastuximab tesirine. IKS03 is also highly effective in patient-derived xenograft models that contain some of the genetic alterations commonly found in relapsed/refractory NHL patients. Results from toxicology studies in cynomologus monkey suggest a manageable safety profile at single doses, well above those required for in vivo activity. Pharmacokinetics are favorable with a mean total ADC half-life of 8 days and undetectable levels of the active PBD payload in circulation confirming targeted delivery of the payload. Study Design and Methods: This Phase 1 multicenter, open label, non-randomized study of IKS03 will consist of two parts: dose-escalation (Part I) and dose-expansion (Part II) together enrolling approximately 140 adult patients with relapsed or refractory B-cell NHL after at least two prior lines of systemic therapy. Patients will receive repeat doses of study drug by IV infusion on Day 1 of each 21-day cycle, until disease progression, unacceptable toxicity, or another withdrawal criterion is met. Key exclusion criteria include: active central nervous system involvement with NHL; clinically significant cardiovascular, pulmonary or hepatic disease; or receipt of other CD19-directed therapy within 3 months. Part I dose escalation will enroll patients with confirmed CD19-positive, measurable or non-measurable advanced B-cell NHL. Eligible subtypes include DLBCL, MCL, FL, high-grade B-cell, and marginal zone lymphoma as per WHO 2016 classification. Patients with Burkitt's lymphoma, Waldenström macroglobulinemia, and chronic lymphocytic leukemia are excluded. In Part 1, the primary objective is establishment of the recommended Phase 2 dose (RP2D) by evaluation of safety, tolerability and the maximum tolerated dose (MTD) of IKS03. Dose escalation will follow a 3+3 design. A two cycle Dose-Limiting Toxicity (DLT) assessment period will be observed, and dose-escalation decisions will be guided by a study safety committee. Dose escalation increments will be adjusted based on occurrence of protocol-specified DLTs as well as overall tolerability. Secondary objectives include characterization of immunogenicity and pharmacokinetic (PK) profile of IKS03. Exploratory objectives include preliminary antineoplastic activity per Lugano criteria (Cheson et al, JCO 2014) and evaluation of pharmacodynamic markers. Part II will further evaluate the antineoplastic activity of IKS03 at the RP2D in expansion cohorts of patients with selected NHL subtypes and with measurable disease. Sample size will be determined for each subtype using a Simon Two-Stage design. Secondary objectives include further evaluation of safety, tolerability, immunogenicity and PK profile of IKS03 as well as confirmation of the RP2D. Clinical trial information: NCT05365659.

Comparison of Bendamustine Versus Fludarabine/ Cyclophosphamide Lymphodepletion in Adult Patients Receiving CD19 CAR-T Cell Therapy

INTRODUCTION: Lymphodepleting chemotherapy (LDC) prior to CAR-T infusion is required for more effective expansion and persistence of infused T cells. Most commonly, fludarabine and cyclophosphamide (flu/cy) has been used. Given recent drug shortages, alternative chemotherapeutic agents such as bendamustine have been used, although limited data exists to evaluate its safety and efficacy. Our study aimed to investigate the outcomes and toxicity profile associated with the use of bendamustine compared to flu/cy LDC in patients receiving CD19 CAR T cells for B-cell non-Hodgkin lymphoma (B-NHL). METHODS: In this retrospective analysis we included patients with relapse/ refractory B-NHL (follicular lymphoma (FL), mantle cell lymphoma (MCL), and large B cell lymphoma (LBCL)) treated with commercial CD19 CAR-T from Memorial Sloan Kettering Cancer Center (MSKCC) and Hackensack Meridian Health (HMH) between January 2020 to December 2022. We compared the outcomes and toxicity of those patients who received bendamustine LDC to historical controls treated with flu/cy. Response and toxicities including CRS and ICANS were assessed using the Lugano 2014 and ASTCT criteria, respectively. RESULTS: Two hundred and forty-two B-NHL (21 FL, 25 MCL, 196 LBCL) patients underwent CAR-T infusion, with 179 receiving flu/cy and 63 receiving bendamustine LDC. Baseline characteristics were comparable in each group except for number of lines of prior therapy, with the bendamustine group having received a median of 2 lines of prior therapy compared to 3 lines in the flu/cy group (p = 0.005). Patients with LBCL receiving bendamustine LDC had overall lower rates of all grade CRS (58% vs. 83%, p < 0.001), and all grade ICANS (6% vs. 31%, p < 0.001), as well as grade 3+ CRS (0% vs. 28%, p = 0.6) and grade 3+ ICANS (0% vs. 12%, p = 0.004). Additionally, LBCL patients receiving bendamustine had lower rates of D+30 neutropenia (absolute neutrophil counts 2.05 versus 1.40, p = 0.02), and a lower cumulative incidence of febrile neutropenia at D+30 (6.2% (95% CI 1.6 - 16) versus 38% (95% CI 30-46%)). The median follow-up for patients with LBCL who received bendamustine LDC was 4.3 months (95% CI 3.8 - 6) and 13 months (95% CI 12-17) in those receiving flu/cy LDC. Analysis of the best overall response rate (ORR) by day 100 of the LBCL cohort did not reveal any significant difference based on the type of LDC received (70% versus 77%, respectively, p = 0.4). Within the LBCL group, there was no significant difference in the bendamustine versus flu/cy groups with the estimated 1-year progression free survival at 40% (95% CI 25-64) versus 42% (95% CI 33-52) (Figure 1), and 1-year overall survival of 76% (95% CI 61-93) versus 68% (95% CI 59-77), respectively. CONCLUSIONS: Bendamustine LDC appears to be a satisfactory LDC agent with a more favorable toxicity profile compared to flu/cy in patients receiving CD19 CAR T cells for B-NHL. While we noted comparable outcomes between the two groups, the short follow-up time in the bendamustine group currently limits a clearer assessment of potential differences in survival between the two groups. Longer follow up is necessary to ensure responses are sustained in those receiving bendamustine.

A Phase 1 Study of PIT565, a First-in-Class, Anti-CD3, Anti-CD19, Anti-CD2 Trispecific Antibody in Patients with Relapsed and/or Refractory B-Cell Malignancies

Background and Significance: There is an unmet therapeutic need for patients with relapsed and/or refractory (R/R) B-cell non-Hodgkin lymphoma (B-NHL) and R/R B-cell acute lymphoblastic leukemia (B-ALL) who have failed multiple lines of therapy. PIT565 is an investigational, first-in-class, immunoglobulin G-like, trispecific antibody that targets CD19 on malignant B cells while engaging CD3 and CD2 (a costimulatory receptor) on T cells, leading to redirected T-cell cytotoxicity toward CD19-positive malignant B cells. CD2 signaling prevents transcriptional changes characteristic of exhaustion during persistent T-cell receptor stimulation of CD8 T cells. Furthermore, the loss of CD2 ligand, CD58, on tumor cells has been shown to mediate resistance to the antitumor activity by T cell-redirecting therapies, confirming the importance of CD2 activation in T cells. Findings from preclinical studies suggest that PIT565 mediates more potent and sustained antitumor T-cell responses compared with CD3 bispecifics (Lu H, ASH 2022). Study Design and Methods: This is an open-label, phase 1, multicenter study of PIT565 in patients with R/R B-NHL and R/R CD19-positive B-ALL who have relapsed/failed to respond to ≥2 lines of prior therapy (including an anti-CD20 monoclonal antibody-containing chemotherapy combination regimen for patients with R/R B-NHL) (NCT05397496). The study is ongoing with plans to enroll approximately 140 patients in Belgium, France, Israel, Italy, Japan, Singapore, Spain, and the USA. Eligible patients are ≥18 years with an Eastern Cooperative Oncology Group performance status ≤2 and have at least one bi-dimensionally measurable nodal lesion or one bi-dimensionally measurable extranodal lesion as measured via positron emission tomography-computed tomography for R/R B-NHL, and/ or morphologic disease in the bone marrow (³5% blasts) for R/R B-ALL. Patients with contraindication to tocilizumab; history of other malignant disease; active central nervous system involvement; autoimmune disease (other than patients with vitiligo, hypothyroidism only requiring hormone replacement, or psoriasis not requiring systemic treatment or conditions not expected to recur); or receiving systemic treatment with any immunosuppressive medication are not eligible. During the dose escalation part of the study, PIT565 is administered to patients with R/R B-NHL (Group A) and patients with R/R B-ALL (Group B). During the dose-expansion part, PIT565 is administered to patients with R/R large B-cell lymphoma (LBCL) who have received CD-19-directed chimeric antigen receptor (CAR)-T therapy (Group A1); patients with R/R LBCL who have not received CAR-T therapy (Group A2); and patients with R/R B-ALL (Group B1). PIT565 is administered either once weekly (Q1W) or once every 2 weeks (Q2W) with and without a priming dosing. Routes of administration (intravenous [IV] or subcutaneous [SC]) are explored in the dose-escalation phase. Patients initially receive PIT565 IV Q1W over a 28-day cycle. Q2W treatment in a 28-day cycle is explored if supported by preliminary pharmacokinetics (PK), pharmacodynamics, efficacy, and safety findings. The primary objective is to assess safety (including dose-limiting toxicities) and tolerability, and to identify the maximum tolerated dose (MTD) and/or recommended dose (RD), schedule, and route of administration for each indication. Secondary objectives include evaluation of preliminary antitumor activity (overall response rate, complete response rate, best overall response, duration of response, overall survival, and progression-free survival for B-NHL or event-free survival for B-ALL), assessment of PK and immunogenicity of PIT565 in R/R B-NHL and R/R B-ALL. The dose escalation phase is guided by an adaptive Bayesian logistic regression model following the escalation with overdose control principle. The MTD and/or RD are further explored during the dose-expansion phase.

A Potential Paradigm for the Robust and Systematic Prioritisation of Assets in Academic-Led, Multi-Industry Collaborative Trials in Rare Populations (Glo-BNHL)

Overview Given the rarity of children and adolescents with relapsed and refractory (r/r) B-cell Non-Hodgkin Lymphoma (B-NHL) and the large number of potential agents in development for adult mature B-cell malignancies, there is urgent need for prioritisation of agents as proposed by the ACCELERATE Paediatric Strategy Forum for medicinal development in paediatric B-NHL (Pearson 2019). The process developed for the global platform study Glo-BNHL (published separately) is described here. Prioritisation process Assets submitted for review by industry collaborators are prioritised under Confidentiality Disclosure Agreements by the Glo-BNHL Trial Steering Committee (TSC) comprising expert clinicians, statisticians and patient representatives. The assessment includes a quantitative element addressing each of the following areas, with greater weighting given to more relevant criteria such as paediatric-specific and clinical data. Target and scientific rationaleAsset position within current prioritisation strategy*Pre-clinical data evaluating in vitro sensitivity, including the number, heterogeneity and relevance of cell lines tested and quality of the submitted elements of evidencePre-clinical data evaluating in vivo activity of the asset including the number, type and relevance of models and quality of the elements of evidence submittedClinical data regarding monotherapy efficacy in single arm and randomised trials, including the disease-type and therapeutic regimen studiedClinical data regarding combination efficacy (if studied)Clinical data regarding safety of the agent with regard to frequency, severity and modifiability of adverse events, including applicability to the paediatric populationFeasibility of delivery in paediatrics, including formulation and dose-confirmation processes *Classes of novel agents prioritised for inclusion at the initiation of the trial were: (1) Bispecific antibodies (2) antibody-drug conjugates (3) chimeric antigen receptor T-cell products. The TSC has committed to updating this list as the field evolves. The assessment also includes a qualitative element incorporating expert opinion regarding relevance of the target, mechanism of action, and overall impression of the asset. These elements are combined to inform the final discussion before a decision is made. A formal written response from the Sponsor and TSC Chair outlining the TSC decision on whether the asset has been prioritised for evaluation within Glo-BNHL, and associated rationale, is issued to the relevant industry partner (now also copied to the European Medicines Agency (EMA)) within 28 days of receipt of the asset information pack. A follow-up clarification meeting is offered. For prioritised assets, following agreement from the relevant industry partner, the process of formal inclusion in Glo-BNHL then begins. Scope of assets reviewed Between September 2020 and June 2023, information packs for 7 assets were submitted for review from 6 pharmaceutical companies. The assets spanned 5 classes of drugs: 3 bispecific antibodies, 1 antibody-drug conjugate, 1 chimeric antigen receptor T-cell product, 1 small molecule inhibitor and 1 immunomodulator. Formal responses were issued within a median of 20 days (mean 21.3 days) followed by a clarification meeting on 5 occasions. Prioritised assets Four of the 7 reviewed assets were prioritised for inclusion within Glo-BNHL. At time of planned opening only 2 of these assets are included. The other 2 assets are being investigated in industry-led competitive trials. A further asset was deemed to be of potential interest but insufficient data were available due to the early stage of development to reach a final conclusion (further review pending). Non-prioritised assets The rationale for non-prioritisation of assets included irrelevant target in paediatric B-NHL, insufficiently convincing mechanism of action, and lack of superiority over other agents within a non-prioritised class. The EMA has subsequently waived the obligation to submit the results of paediatric B-NHL studies for both non-prioritised assets reasoning they do not represent potential for significant therapeutic benefit. Summary The Glo-BNHL international platform trial prioritisation process represents a model for handling the challenge of development of multiple potential agents in very rare populations in the global arena.

C-CAR039, a Novel Anti-CD20/CD19 Bi-Specific CAR T-Cell Therapy Shows Deep and Durable Clinical Benefits in Patients with Relapsed or Refractory (r/r) B-Cell Non-Hodgkin Lymphoma (B-NHL) in Long Term Follow up

Background: We previously reported that C-CAR039, an autologous anti-CD20/CD19 bispecific chimeric antigen receptor (CAR) T-cell therapy, demonstrated a favorable safety profile and promising efficacy in patients (pts) with r/r B-NHL. Of the initial 28 pts treated with C-CAR039 with a median of 3 prior lines of therapy. Only 1 patient experienced grade ≥3 cytokine release syndrome (CRS), and no patient reported grade ≥2 immune effector cell-associated neurotoxicity syndrome (ICANS). The overall response rate (ORR) was at 92.6%, with 85.2% complete response (CR). After a median follow-up of 7 months, 74.1% of pts remained in CR, and the Kaplan-Meier (KM) estimation of progression-free survival (PFS) at 6 months was 83.2%. (Liang et al. ASCO 2021. #2507). Here we present the updated results to include more pts (48 pts) and a longer duration of follow-up (median 23.9 months). Methods: This is an open-label, dose escalation and expansion investigator-initiated trial (IIT) of C-CAR039. This trial was conducted at 4 sites to determine the safety and efficacy of C-CAR039 in pts with r/r B-NHL. Pts with r/r diffuse large B cell lymphoma (DLBCL), primary mediastinal large B cell lymphoma (PMBCL), follicular lymphoma (FL) or mantle cell lymphoma (MCL) were enrolled and received a single C-CAR039 infusion at a dose of 1.0-5.0x10 6 CAR-T cells/kg after a 3-day conditioning chemotherapy. The primary objective was to assess the safety and tolerability. CRS and ICANS were graded according to ASTCT 2019 criteria. The secondary objectives were to evaluate C-CAR039 efficacy and pharmacokinetics. Response was assessed per Lugano 2014 criteria. Results: Between Nov 5, 2019, and Jan 11, 2022, 48 pts received C-CAR039 manufactured using Miltenyi Biotec CliniMACS Prodigy® System. Of the 48 pts, 44 pts had large B-Cell Lymphoma (LBCL) (DLBCL, n = 37; PMBCL, n = 3; tFL, n=4), 3 pts had FL and 1 patient had MCL. The median age was 55 (range, 25-71) years, and 11 (22.9%) pts were ≥ 65 years. Thirty-six (75%) pts were in Ann Arbor Stage III/IV with 3 median prior lines of therapy (range, 1-7). All pts received anti-CD20 antibody and alkylating agents. Eight (16.7%) pts had prior ASCT, 32 (66.7%) pts were refractory to their last treatment, and 22 (45.8%) pts never achieved CR to their prior therapies. Prior to C-CAR039 infusion, 12 (25%) pts received bridging therapy. As of Jan 15, 2023, 45 pts (93.8%) experienced CRS, of which 44 (91.7%) pts reported grade 1 or 2, only 1 (2.1%) patient experienced grade 3 CRS. Median time to CRS onset was 3 days (range, 1-12), with median duration of 5 days (range, 2-78). Three pts had ICANS at a dose of 5.0x10 6 CAR-T cells/kg, of which 2 were grade 1 and 1 was grade 2. The median time to onset of ICANS was 6 days (range, 5-29), with a median duration of 12 days (range, 3-53). All CRS and ICANS were resolved. Grade ≥3 neutropenia, anemia, thrombocytopenia and infection were reported in 83.3%, 14.6%, 27.1% and 10.4% of pts, respectively. Second primary malignancy after C-CAR039 infusion were observed in 3 pts; 2 acute myeloid leukemia (AML) occurred at 2 and 10 months, and 1 Epstein-Barr virus-positive cytotoxic T-cell lymphoma was at 8 months, the tumor biopsy was tested with qPCR and CAR transgene was negative and none were related to C-CAR039. Twelve deaths occurred, 9 due to disease progression, 2 due to AE of AML, and 1 due to unknown cause. Of the 48 pts, 47 pts were evaluable for efficacy (1 patient with DLBCL had no measurable disease at baseline). The ORR and CR rate among evaluable pts were 91.5% and 85.1% respectively. Median time to first response and CR was 1.0 month (range, 0.9-1.9) and 1.1 month (range, 0.9-8.9), respectively. Of the 43 LBCL pts, the ORR was 90.7%, with 86.0% CR. Median DOR, PFS and OS were not reached. The KM estimation of PFS and OS rate at 24 months was 66.0% (95%CI 53.2%-81.9%) and 77.9% (95% CI, 66.6%-91.1%) respectively. C-CAR039 showed cellular kinetic profile consistent with commercial CAR-T therapies. In 48 evaluable pts, the median T max was 11.5 day (range, 7-31), the median C max was 139,416 copies/g gDNA (range, 708-962,445), and the median AUC 0-28day was 1,513,442 copies/ug∙day (range, 3,818-11,594,912.5). Conclusions: At a longer median follow-up of 23.9 months, C-CAR039 demonstrated a favorable safety profile with deep and durable response in pts with r/r B-NHL, especially in LBCL pts.

Senza5 TM CART5: An Autologous CD5-Deleted Anti-CD5 CART Product with Enhanced Anti-T-Cell Lymphoma Activity

Introduction: Treatment with adoptive T cell therapies expressing Chimeric Antigen Receptors (CART) produces unprecedented clinical responses in relapsed or refractory (r/r) B-cell acute lymphoblastic leukemia (B-ALL), non-Hodgkin lymphomas (NHL), and multiple myeloma. Despite the transformative potential of these therapies for cancer, most patients treated with CART therapy experience incomplete responses or eventual relapse. Moreover, CART therapy is not yet effective for solid cancers or other hematological malignancies such as T-cell neoplasms. Thus, there is a dire need to enhance CART efficacy and extend this approach to more cancer types. We previously presented preliminary preclinical results of CD5-directed CAR-T cells (CART5) that had CD5 knocked out (KO) [ Blood (2020) 136 (Supplement 1): 51-52]. CD5 KO not only prevented CART fratricide but also dramatically enhanced CART function in multiple in vivo models. Enhanced CART function reflected disinhibition of early T-cell activation by abrogating CD5 signaling. Here, we combine the functional advantage of CD5 KO CART5 with a clinical-grade “rapid” 5-day manufacturing process, characterize the resulting drug product, and evaluate its in vivo antitumor efficacy in a human xenograft model of T-cell lymphoma/leukemia. Methods and Results: Using normal healthy donor T cells, we developed a proprietary, “rapid” 5-day GMP-validated manufacturing process for CD5 KO CART5, completing the process in 5 days (CART5 rapid) instead of the conventional 14+ days (CART5 conv). At the end of manufacturing, the two products possessed similar ratios of CD8 + and CD4 + T cells, CD5 editing, and CAR5 expression. The CART5 rapid product did not exhibit any genetic or functional abnormalities characteristic of tumorigenic risk, demonstrated by low off-target gene editing in low-risk genes, no in vitro soft agar colony formation, and normal karyotypes. Importantly, the CART5 rapid manufacturing process did not skew TCRβ profiles, indicating that the CART5 rapid product retains a diverse T-cell repertoire. CD5 KO CART5 rapid cells possessed high specificity for T-cell leukemia/lymphoma, reflected by the absence of recognition of ex vivo normal human cells (cardiomyocytes, hepatocytes, neurons, monocytes, etc). Interestingly, CD5 KO CART5 rapid cells possessed a more central memory-like phenotype than CD5 KO CART5 conv cells which has been correlated with improved clinical efficacy. To compare their antitumor efficacy, we performed an in vivo experiment with CD5 + Jurkat cells utilizing a suboptimal dose of CART5 cells. Immunodeficient NSG mice were engrafted with 10 6 Jurkat cells on day -7 and treated intravenously on day 0 with a suboptimal dose (0.5x10 6 CAR + cells) of CD5 KO CART5 rapid or CD5 KO CART5 conv cells. Controls received an equivalent total number of Mock KO UTD conv. Mice treated with CD5 KO CART5 rapid cells demonstrated superior antitumor responses compared to CD5 KO CART5 conv. Improved tumor control correlated with dramatically increased overall survival of mice treated with CD5 KO CART5 rapid (median overall survival Mock KO UTD = 21 days; CD5 KO CART5 conv = 44 days vs. CD5 KO CART5 rapid = not reached, p=0.0019, Mantel-Cox; Figure 1). Conclusion: This novel CD5 KO anti-CD5 CART product manufactured in a 5-day GMP process shows high specificity and significantly enhanced antitumor efficacy resulting from the synergistic effect of improved early T-cell activation due to CD5 deletion and preservation of T-cell memory phenotypes conferred by a novel, 5-day manufacturing processes. Autologous Senza5 TM CART5 for the treatment of CD5 + nodal T-cell lymphomas is expected to enter the clinic in a Phase I study later this year.

First Report of Phase 1 Studies of DZD8586, a BBB Penetrant LYN/BTK Dual Inhibitor, in Patients with B-Cell Non-Hodgkin Lymphoma (B-NHL)

Introduction Resistance to covalent (ibrutinib, acalabrutinib and zanubrutinib) and non-covalent BTK inhibitors (pirtobrutinib) is an emerging clinical challenge. DZD8586 was designed as a full blood-brain barrier (BBB) penetrable LYN/BTK dual inhibitor. Preclinical study suggested DZD8586 has a good selectivity against other TEC family kinases (TEC, ITK, TXK, BMX). DZD8586 inhibits BTK-dependent and BTK-independent BCR signaling pathways by targeting LYN and BTK, which could potentially overcome resistance to both covalent and non-covalent BTK inhibitors for the treatment of CLL and MCL, as well as DLBCL. Two phase 1 clinical studies are ongoing in patients with relapsed or refractory (r/r) B-NHL to assess safety, pharmacokinetics (PK), pharmacodynamics (PD) and anti-tumor efficacy of DZD8586. Methods TAI-SHAN1 (NCT05844956; CTR20220558) and TAI-SHAN5 (NCT05824585) are phase 1 dose escalation and expansion studies in patients with r/r B-NHL. Both studies have similar dose escalation strategies. Patients who progressed following or intolerant of prior systemic therapy were enrolled. Pooled safety and efficacy analysis was performed. In addition, modulation of PD biomarkers was also evaluated. Tumor responses were investigator assessed according to Lugano 2014, IPCG 2005, or iwCLL 2018, as appropriate. Results As of June 15, 2023, 17 patients with r/r B-NHL have been enrolled and received DZD8586 at doses ranging from 10 to 100 mg once daily (QD) (10 mg， n=1；25 mg， n=4；50 mg， n=7；100 mg， n=5). The median age was 61 years, 71% were male, and 53% had an ECOG PS of 1. Histological subtypes included CLL, SCNSL, DLBCL, MCL, FL and MZL. The median number of prior therapies was 3 (range 2 - 8). All patients received prior chemotherapy and anti-CD20 therapy. Six patients, including 1 CLL, 2 MCL, 1 MZL, 1 SCNSL and 1 DLBCL had received prior treatment with covalent BTK inhibitors. DZD8586 was well tolerated across the doses investigated. Drug-related treatment emergent adverse events (TEAEs) reported in > 2 patients included thrombocytopenia (10/17), neutropenia (5/17), and upper respiratory tract infection (3/17). The most common ≥ grade 3 TEAE was thrombocytopenia (3/17, all at 100 mg). Other ≥ grade 3 TEAEs, including neutropenia, drug eruption and upper respiratory tract infection, were each reported by one patient. Bleeding, atrial fibrillation, and arthralgia were not reported. Grade 1 diarrhoea was reported in one patient. The maximum tolerated dose was defined as 100 mg QD. All these TEAEs were reversible after dose interruption and/or with supportive care. The longest duration on treatment was 10+ months. Among 13 patients treated at doses ≥ 25 mg QD with at least one tumor assessment, the objective response rate (ORR) was 9/13 (69.2%). Responses were observed across different histological subtypes (1/2 in SCNSL; 4/5 in DLBCL; 1/2 in FL; 1/1 in MCL, 1/2 in MZL and 1/1 CLL carrying C481S mutation). Among the 5 evaluable BTKi treated patients, tumor responses were observed in 3 patients. The longest duration of response (DoR) was 6.4+ months, and the patient was still ongoing with DZD8586 treatment and responding. PK was generally dose-proportional across the dose ranges of 10 to 100 mg. DZD8586 was absorbed with median t max 1.5 hours, and eliminated with mean terminal half-life of ~18 hours. Accumulation of about two folds in AUC was noted at steady state following once daily dosing. Dose dependent pBTK modulation in whole blood cells was detected, and at the doses ≥ 25 mg, sustained pBTK inhibition was observed. The unbound CSF-to-plasma concentration ratio (K puu,CSF) was 1.2 from one CNSL patient with available CSF samples, suggesting excellent CNS penetration of DZD8586 in humans. Conclusion In the preliminary pooled analysis of two ongoing phase 1 trials, DZD8586 has encouraging anti-tumor activity and safety in heavily pre-treated B-NHL patients. The combination of BBB penetration, dual inhibition of LYN/BTK and potential to overcome C481S mutant CLL and other covalent BTKi resistant lymphomas suggest this may be a useful agent. Updated data will be presented at the meeting.

Impact of ARID1A and TP53 mutations in pediatric refractory or relapsed mature B-Cell lymphoma treated with CAR-T cell therapy

BackgroundChimeric antigen receptor (CAR)-T cell therapy has been used to treat pediatric refractory or relapsed mature B-cell non-Hodgkin lymphoma (r/r MB-NHL) with significantly improved outcomes, but a proportion of patients display no response or experience relapse after treatment. To investigate whether tumor-intrinsic somatic genetic alterations have an impact on CAR-T cell treatment, the genetic features and treatment outcomes of 89 children with MB-NHL were analyzed.Methods89 pediatric patients treated at multiple clinical centers of the China Net Childhood Lymphoma (CNCL) were included in this study. Targeted next-generation sequencing for a panel of lymphoma-related genes was performed on tumor samples. Survival rates and relapse by genetic features and clinical factors were analyzed. Survival curves were calculated using a log-rank (Mantel-Cox) test. The Wilcox sum-rank test and Fisher’s exact test were applied to test for group differences.ResultsA total of 89 driver genes with somatic mutations were identified. The most frequently mutated genes were TP53 (66%), ID3 (55%), and ARID1A (31%). The incidence of ARID1A mutation and co-mutation of TP53 and ARID1A was high in patients with r/r MB-NHL (P = 0.006; P = 0.018, respectively). CAR-T cell treatment significantly improved survival in r/r MB-NHL patients (P = 0.00081), but patients with ARID1A or ARID1A and TP53 co-mutation had poor survival compared to those without such mutations.ConclusionThese results indicate that children with MB-NHL harboring ARID1A or TP53 and ARID1A co-mutation are insensitive to initial conventional chemotherapy and subsequent CAR-T cell treatment. Examination of ARID1A and TP53 mutation status at baseline might have prognostic value, and risk-adapted or more effective therapies should be considered for patients with these high-risk genetic alterations.

Incorporating radiation with anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory non-Hodgkin lymphoma: A multicenter consensus approach.

Anti-CD19 chimeric antigen receptor T-cell therapy (CART) has revolutionized the outcomes of relapsed and/or refractory B-cell non-Hodgkin lymphoma. However, CART is still limited by its availability, toxicity, and response durability. Not all patients make it to the CART infusion phase due to disease progression. Among those who receive CART, a significant number of patients experience life-threatening cytokine release syndrome toxicity, and less than half maintain a durable response with the majority relapsing in pre-existing sites of disease present pre-CART. Radiation therapy stands as a promising peri-CART and salvage treatment that can improve the outcomes of these patients. Evidence suggests that bridging radiotherapy prior to CART controls the disease during the manufacturing period, augments response rates and local control, cytoreduces/debulks the disease and decreases the severity of cytokine release syndrome, and may prolong disease-free intervals and survival especially in patients with bulky disease. Consolidative radiotherapy for residual post-CART disease alters the pattern of relapse and improves local recurrence-free and progression-free survivals. Salvage radiotherapy for relapsed post-CART disease has favorable survival outcomes when delivered comprehensively for patients with limited relapsed disease and palliates symptoms for patients with diffuse relapsed disease. The biology of the disease during the peri-CART period is poorly understood, and further studies investigating the optimal timing and dosing of radiation therapy (RT) are needed. In this review, we tackle the most significant challenges of CART, review and propose how RT can help mitigate these challenges, and provide The Mayo Clinic experts' approach on incorporating RT with CART.

Tislelizumab augment the efficacy of CD19/22 dual-targeted chimeric antigen receptor T cell in advanced stage relapsed or refractory B-cell non-Hodgkin lymphoma.

Dual-targeted chimeric antigen receptor T (CAR-T) cell is an important strategy to improve the efficacy of CD19 CAR-T cell against refractory or relapsed B cell non-Hodgkin lymphoma (R/R B-NHL). However, durable responses are not achieved in most patients, in part owing CAR-T cell exhaustion caused by PD-1/PD-L1 pathway.We conducted a prospective, single-arm study of dual-targeted CD19/22 CAR-T cell combined with anti-PD-1 antibody, tislelizumab, in R/R B-NHL (NCT04539444). Tislelizumab was administrated on +1day after patients received infusion of CD19/22 CAR-T cell. Responses, survival and safety were evaluated. From 1 August 2020 to 30 March 2023, 16 patients were enrolled. The median follow-up time is 16.0 (range: 5.0-32.0months) months. Overall response was achieved in 14 of 16 (87.5%) patients, and the complete response (CR) was achieved in 11 of 16 (68.8%) patients. The 1-year progression-free survival and overall survival rates were 68.8% and 81.3%, respectively. Of the 14 patients responded, 9 patients maintained their response until the end of follow-up. Among the 15 out of 16 (93.8%) patients who had extranodal involvement, 14 (93.3%) patients achieved overall response rate with 11 (73.3%) patients achieving CR. Eight (50%) patients experienced cytokine release syndrome. No neurologic adverse events were reported. Gene Ontology-Biological Process enrichment analysis showed that immune response-related signaling pathways were enriched in CR patients. Our results suggest that CD19/22 CAR-T cell combined with tislelizumab elicit a safe and durable response in R/R B-NHL and may improve the prognosis of those patients.