Lenz, Georg

LBA7000 Background: ~40% of DLBCL pts are not cured with first-line (1L) R-CHOP, underscoring a significant unmet need for more effective 1L regimens. Tafa (anti-CD19 mAb) + Len-R-CHOP in the phase 1b First-MIND study demonstrated safety and efficacy in pts with newly diagnosed disease. frontMIND, a phase 3, double-blind, placebo-controlled study, compared Tafa-Len-R-CHOP vs R-CHOP in pts with high-risk aggressive BCLs. Methods: Pts aged 18–80 y with newly diagnosed, high-intermediate/high-risk DLBCL or HGBL (IPI 3–5, aaIPI 2–3 if ≤60 y) and ECOG PS 0–2 were randomized 1:1 to Tafa-Len-R-CHOP or R-CHOP. Primary endpoint was investigator-assessed PFS; secondary endpoints included: EFS, OS, CR, ORR, safety. Results: At primary analysis (data cutoff Oct 20, 2025), 899 pts were randomized to Tafa-Len-R-CHOP (n=448) or R-CHOP (n=451); baseline characteristics were similar between arms. With a median follow-up of 35.2 mo, Tafa-Len-R-CHOP achieved a statistically significant improvement in PFS vs R-CHOP (HR 0.75 [95% CI: 0.59, 0.96]; P =0.019) in the overall population; in pts with centrally confirmed lymphoma subtypes (n=773), PFS HR was 0.68 (95% CI: 0.52, 0.88) and 24-mo PFS was 72.7% vs 62.2%. PFS benefit was observed with Tafa-Len-R-CHOP in both molecular COO subtypes, ABC and GCB (data will be presented). Tafa-Len-R-CHOP significantly improved EFS vs R-CHOP; CR and ORR were similar between arms and HR for OS was 0.85 (final OS planned at 5y) (Table). Any-grade TEAEs were similar in treatment arms (98.6% vs 97.1%); more grade ≥3 TEAEs occurred with Tafa-Len-R-CHOP vs R-CHOP (86.7% vs 76.1%). Discontinuations due to TEAEs occurred in 25.7% vs 17.9% and deaths due to TEAEs in 5.9% vs 3.8% of pts for Tafa-Len-R-CHOP vs R-CHOP. Overall, there were fewer deaths with Tafa-Len-R-CHOP vs R-CHOP (18.5% vs 21.7%). Conclusions: The primary endpoint of frontMIND was met; Tafa-Len-R-CHOP resulted in a significant 25% reduction in risk of disease progression or death compared with R-CHOP, with an 8.2% difference in 24-month PFS rate in the overall population and 10.5% difference in pts with centrally confirmed lymphoma subtypes. TEAEs were manageable and consistent with the expected safety profile. Tafa-Len-R-CHOP represents a potential new 1L standard of care for pts with both COO subtypes of high-risk DLBCL or HGBL. Clinical trial information: NCT04824092 . Efficacy outcomes by treatment arm.* Variable Tafa-Len-R-CHOP(n=448) R-CHOP(n=451) HR or OR(95% CI) P value PFS, # events (%) † 121 (27.0) 155 (34.4) 0.75 (0.59, 0.96) 0.019 PFS rate at 24 mo, % 71.1 62.9 − − PFS rate at 36 mo, % 67.3 60.7 − − EFS, # events (%) 154 (34.4) 191 (42.4) 0.79 (0.64, 0.97) 0.026 OS, # events (%) 82 (18.3) 95 (21.1) 0.85 (0.63, 1.14) 0.270 CR at EOT, n (%) 292 (65.2) 294 (65.2) 0.998 (0.76, 1.31) 0.987 ‡ ORR at EOT, n (%) 360 (80.4) 343 (76.1) 1.290 (0.94, 1.78) 0.120 ‡ *Investigator-assessed. † Progressive disease or death from any cause. ‡ Nominal P value.

PURPOSE The combination of the Bruton tyrosine kinase inhibitor ibrutinib with bendamustine-rituximab for first-line treatment of mantle cell lymphoma (MCL) prolonged progression-free survival (PFS), but without improvement in overall survival (OS), likely because of toxicity. Acalabrutinib was shown to be efficacious and less toxic than ibrutinib in a head-to-head trial in chronic lymphocytic leukemia and therefore might lead to better outcomes in MCL. METHODS Patients 65 years and older with previously untreated MCL received acalabrutinib (100 mg twice daily) or placebo (until disease progression or unacceptable toxicity), plus six cycles of bendamustine (90 mg/m 2 once daily; days 1 and 2) and rituximab (375 mg/m 2 as a single dose; day 1) followed by rituximab maintenance in responding patients for 2 years. Crossover to acalabrutinib at disease progression was permitted. The primary end point was PFS per the independent review committee; overall response rate and OS were secondary end points. RESULTS In total, 598 patients were randomly assigned, with 299 in each arm. At a median follow-up of 49.8 months using the reverse Kaplan-Meier method, the median PFS was 66.4 months in the acalabrutinib arm and 49.6 months in the placebo arm (hazard ratio [HR], 0.73 [95% CI, 0.57 to 0.94]; P = .0160). Benefit was seen across all subgroups, including those with high-risk features. Overall response/complete response rates were 91.0%/66.6% and 88.0%/53.5% in the acalabrutinib and placebo arms, respectively. OS was not significantly different (HR, 0.86 [95% CI, 0.65 to 1.13]; P = .27). Grade 3 or greater adverse events were reported in 88.9% and 88.2% in the acalabrutinib and placebo arms, respectively. CONCLUSION The combination of acalabrutinib with bendamustine-rituximab significantly improved PFS. Clinical benefit of acalabrutinib with bendamustine-rituximab was achieved with manageable toxicity.

Introduction Plasmablastic lymphoma (PBL) is a rare aggressive subtype of lymphoma. It is more common in HIV positive patients, and is often associated with Epstein-Barr virus (EBV) and MYC rearrangements. PBL is characterized by markers of plasmacytic differentiation including CD138 and MUM1/IRF4, and loss of B-cell markers such as CD20, which suggests a cell of origin similar to that of multiple myeloma (MM) or activated B-cell-like (ABC) diffuse large B-cell lymphoma (DLBCL). The standard of care for PBL is CHOP-based chemotherapy but this is frequently not curative. Other than EBV-negative status, which defines a high-risk group, no other biological features have been discovered that are associated with outcomes. Methods Here, we provide a comprehensive analysis of the genomic and transcriptomic landscape of PBL using a collection of 176 exomes and genomes (n=55 new, contributed by Lymphoma/Leukemia Molecular Profiling Project [LLMPP] sites and centrally reviewed by the LLMPP pathology panel [WHO 2016]; n=121 previously published [PMID: 33225311, 33951889, 34465776, 34714908]), 65 transcriptomes (n=44 new; n=21 published) and 37 in situ single cell transcriptomic profiles (CosMx Spatial Molecular Imager) from archival diagnostic tissue biopsies. Somatic mutations (SNVs/Indels) were identified using an ensemble of four variant callers (Strelka2, Lofreq, Mutect2, SAGE). Salmon and DESeq2 were used to identify differentially expressed genes. This multi-omics dataset was compared to other known B-cell malignancies including 92 MM, 238 Burkitt lymphomas (BL), and 208 DLBCLs. Cell segmentation of the CosMx data was performed using Baysor and downstream analyses were conducted using the Seurat workflow. For functional validation, cell viability assays (CellTiter-Glo Luminescent Assay) were conducted in the PBL cell line, PBL-1, and 4 control DLBCL cell lines. Results Within the cohort, 63% (106/169) of primary PBL cases were EBV-positive (EBV+) and 57% (82/144) harbored MYC rearrangements (MYC+). When stratifying patients by EBV and MYC rearrangement status, mutations in different genes were enriched in each group: STAT3 occurred in 55% (29/53) of EBV+/MYC+ PBLs; NOTCH1 in 19% (7/36) of EBV+/MYC-; MYC in 24% (6/25) and TP53 in 40% (10/25) of EBV-/MYC+ tumors; TET2 was mutated in 38% (9/24) and KRAS in 25% (6/24) of EBV-/MYC- PBLs. EBV-/MYC+ tumors represented a subgroup of patients with dismal outcomes. The 2-year overall survival (OS) of these patients was 22% compared to 61%, 78%, and 54% of EBV+/MYC+, EBV+/MYC-, and EBV-/MYC- PBL patients, respectively (log-rank test p-adj. < 0.05). Consistent with previous studies, we observed recurrent mutations affecting JAK-STAT (STAT3, SOCS1, SOCS3, DUSP2) in 41% of cases and RAS-RAF (NRAS, KRAS, BRAF) signaling in 38% of all PBLs. In contrast to ABC-DLBCL, very few mutations occurred in the NF-κB signalling pathway. Accordingly, PBL showed marked downregulation of genes involved in B-cell receptor and NF-κB signaling. Consistent with the lack of reliance on these pathways, functional analyses in PBL-1 showed resistance to treatment to ibrutinib as well as PI3K- and MALT1-inhibitors. Moreover, constitutive expression of the IκBα super-repressor did not affect viability of PBL-1 cells. In situ single cell transcriptomic data analyses showed a sparse tumor microenvironment (TME) in PBL, with the primary non-malignant cell types being, on average, 10% macrophages, 7% NK/T cells, and 4% stromal cells of all represented cell types. EBV+/MYC+ tumors displayed a more abundant immune cell population with higher levels of macrophages (median 12%) and NK/T cells (median 9%), whereas EBV-/MYC- tumors were composed of the lowest levels of immune cells (median 4% macrophages and 1% NK/T cells). With respect to malignant cell phenotypes, we noted a novel population of SPP1-expressing cells that were enriched in EBV+/MYC+ tumors and a population of CD44-expressing cells that were enriched in EBV+/MYC- tumors. Conclusion Here we present novel subgroups of PBL with unique biology and clinical outcomes. We show that PBL does not rely on B-cell receptor signaling, instead relying on potentially targetable vulnerabilities in JAK-STAT, NOTCH, and RAS-RAF signaling according to EBV positivity and MYC rearrangement status. Lastly, we provide insight into the TME of PBL and demonstrate a novel population of SPP1 and CD44 expressing malignant cells in EBV+ tumors.

Abstract With the introduction of large-scale molecular profiling methods and high-throughput sequencing technologies, the genomic features of most lymphoid neoplasms have been characterized at an unprecedented scale. Although the principles for the classification and diagnosis of these disorders, founded on a multidimensional definition of disease entities, have been consolidated over the past 25 years, novel genomic data have markedly enhanced our understanding of lymphomagenesis and enriched the description of disease entities at the molecular level. Yet, the current diagnosis of lymphoid tumors is largely based on morphological assessment and immunophenotyping, with only few entities being defined by genomic criteria. This paper, which accompanies the International Consensus Classification of mature lymphoid neoplasms, will address how established assays and newly developed technologies for molecular testing already complement clinical diagnoses and provide a novel lens on disease classification. More specifically, their contributions to diagnosis refinement, risk stratification, and therapy prediction will be considered for the main categories of lymphoid neoplasms. The potential of whole-genome sequencing, circulating tumor DNA analyses, single-cell analyses, and epigenetic profiling will be discussed because these will likely become important future tools for implementing precision medicine approaches in clinical decision making for patients with lymphoid malignancies.

TPS7590 Background: Up to 40% of patients relapse or are refractory (R/R) to R-CHOP, the current standard of care for diffuse large B-cell lymphoma (DLBCL), indicating an unmet need, particularly in patients with high-intermediate and high-risk disease (IPI 3–5). POLARIX (NCT03274492) evaluated a modified regimen substituting polatuzumab vedotin for vincristine (pola-R-CHP), demonstrating modest improvement in PFS with no OS benefit between treatment arms. The addition of lenalidomide (LEN) to R-CHOP improved both PFS and OS in the ECOG-ACRIN E1412 trial but not in the Phase III ROBUST study, in which a lower dose of LEN was used, despite a positive trend toward 2-year PFS in a subgroup analysis. The chemo-free immunotherapy tafasitamab + LEN has received accelerated approval in the United States (2020), and conditional marketing authorization in Europe and Canada (2021) in adult patients with R/R DLBCL ineligible for ASCT based on L-MIND (NCT02399085). The primary analysis of First-MIND (NCT04134936), a Phase Ib randomized safety study of R-CHOP + tafasitamab ± LEN in patients with previously untreated and newly diagnosed DLBCL, demonstrated that adding tafasitamab + LEN does not impair dosing and scheduling of R-CHOP, with toxicities similar to those expected with R-CHOP alone (ASH 2021; #3556). frontMIND (NCT04824092) will investigate the efficacy and safety of R-CHOP + tafasitamab + LEN vs R-CHOP alone in previously untreated patients with high-intermediate and high-risk DLBCL. Methods: frontMIND is a Phase III, multicenter, randomized, double-blind, placebo-controlled study. Approximately 880 patients are planned to be randomized at ̃350 centers in North and South America, Europe, and Asia-Pacific. Eligible patients aged 18‒80 years with previously untreated local biopsy-proven, CD20+ DLBCL with IPI score 3–5 (age-adjusted IPI 2–3 if ≤60 years), and ECOG PS 0–2 will be enrolled. Patients with transformed lymphoma (except double or triple hit lymphoma) are excluded. Patients will be randomized 1:1 to receive six 21-day (D) cycles of either R-CHOP + tafasitamab (12 mg/kg intravenously, D 1, 8, and 15) + LEN (25 mg orally, D1–10) or R-CHOP + tafasitamab and LEN placebos. Patients will be followed for up to 5 years after the end of treatment. The primary endpoint is investigator-assessed PFS. Secondary endpoints include investigator-assessed event-free survival, OS, safety, and tafasitamab serum concentration (trough and Cmax levels). Sensitivity and specificity of minimal residual disease for early detection of disease progression is an exploratory endpoint; further MRD parameters may also be investigated. The study is funded by MorphoSys AG and conducted with the scientific support of members of the Fondazione Italiana Linfomi and the German Lymphoma Alliance. Clinical trial information: NCT04824092.

Abstract Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.