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Supplementary Table 1. Information regarding the antibody clones used in multiparameter flow cytometry.

Supplementary Figure S1. Lymphoma cells are visualized by immunohistochemical staining for Cyclin D1. A. Mantle zone subtype is characterized by expanded mantle zones consisting of lymphoma cells which surround preserved germinal centers. B. Nodular subtype C. Diffuse subtype.

Supplementary Table 2. T cell levels in diagnostic MCL lymph nodes expressed as median and range of percentage of cells in mononuclear gate.

Purpose: The purpose of this study was to investigate the impact of T-cell subsets on pathologic and clinical features including disease outcome in mantle cell lymphoma (MCL).Experimental Design: Cell populations were investigated using flow cytometry in diagnostic MCL (n = 153) and reactive (n = 26) lymph node biopsies. Levels of tumor cells, T cells, T-cell subsets, and the CD4:CD8 ratio were assessed and related to pathologic and clinical parameters.Results: MCL cases with diffuse and nodular histologic subtypes showed lower levels of T cells, especially CD4+ T cells, than those with mantle zone growth pattern. Both CD3 and CD4 levels were lower in the nodular subtype than in mantle zone (P = 0.007; P = 0.003) and in the diffuse compared with the nodular subtype (P = 0.022; P = 0.015). The CD4:CD8 ratios were inversely correlated to tumor cell proliferation (P = 0.003). Higher levels of CD3+ and CD4+ T cells and higher CD4:CD8 ratios were associated with indolent disease (P = 0.043, 0.021, and 0.003 respectively). In univariate analysis, a high CD4:CD8 ratio, but not the histologic subtype, was correlated to longer overall survival (OS). In multivariate analysis, the CD4:CD8 ratio correlated with OS independently of Mantle Cell Lymphoma International Prognostic Index (MIPI) and high p53 expression (P = 0.023).Conclusion: CD3+, CD8+, and particularly CD4+ T-cell levels are higher in indolent MCL and decrease with more aggressive histology as reflected by a diffuse growth pattern. High CD4:CD8 ratio correlated independently of other high-risk prognostic factors with longer OS, suggesting a prognostic role for T cells in MCL. Clin Cancer Res; 20(23); 6096–104. ©2014 AACR.

SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase (dNTPase) that restricts viral replication in infected cells and limits the sensitivity to cytarabine by hydrolysing its active metabolite, as recently shown in acute myeloid leukemia. Cytarabine is an essential component in the Nordic mantle cell lymphoma protocols (MCL2 and MCL3) for induction and high-dose chemotherapy treatment before autologous stem cell transplantation for younger patients with mantle cell lymphoma (MCL). We here investigated the expression of SAMHD1 in a population-based cohort of MCL (N = 150). SAMHD1 was highly variably expressed in MCL (range, 0.4% to 100% of positive tumor cells). Cases with blastoid/pleomorphic morphology had higher SAMHD1 expression (P = 0.028) and SAMHD1 was also correlated to tumor cell proliferation (P = 0.016). SAMHD1 expression showed moderate correlation to the expression of the transcriptional regulator SOX11 (P = 0.036) but genetic silencing of SOX11 and SAMHD1 by siRNA in MCL cell lines did not suggest mutual regulation. We hypothesized that expression of SAMHD1 could predict short time to progression in patients treated with Cytarabine as part of high-dose chemotherapy. Despite the correlation with known biological adverse prognostic factors, neither low or high SAMHD1 expression correlated to PFS or OS in patients treated according to the Nordic MCL2 or MCL3 protocols (N = 158).

Treatment for patients 60 years with classical Hodgkin lymphoma (cHL) is problematic; there is no gold standard, and outcome is poor. Using the Swedish Lymphoma Registry, we analysed all Swedish patients diagnosed with cHL between 2000 and 2014 (

To survive chemotherapy, lymphoma cells can relocate to protective niches where they receive support from the non-malignant cells. The biolipid 2-arachidonoylglycerol (2-AG), an agonist for the cannabinoid receptors CB1 and CB2, is released by stromal cells in the bone marrow. To investigate the role of 2-AG in lymphoma, we analyzed the chemotactic response of primary B-cell lymphoma cells enriched from peripheral blood of twenty-two chronic lymphocytic leukemia (CLL) and five mantle cell lymphoma (MCL) patients towards 2-AG alone and/or to the chemokine CXCL12. The expression of cannabinoid receptors was quantified using qPCR and the protein levels visualized by immunofluorescence and Western blot. Surface expression of CXCR4, the main cognate receptor to CXCL12, was analyzed by flow cytometry. Phosphorylation of key downstream signaling pathways activated by 2-AG and CXCL12 were measured by Western blot in three MCL cell lines and two primary CLL samples. We report that 2-AG induces chemotaxis in 80% of the primary samples, as well as 2/3 MCL cell lines. 2-AG induced in a dose-dependent manner, the migration of JeKo-1 cell line via CB1 and CB2. 2-AG affected the CXCL12-mediated chemotaxis without impacting the expression or internalization of CXCR4. We further show that 2-AG modulated p38 and p44/42 MAPK activation. Our results suggest that 2-AG has a previously unrecognized role in the mobilization of lymphoma cells by effecting the CXCL12-induced migration and the CXCR4 signaling pathways, however, with different effects in MCL compared to CLL.

Rituximab monotherapy is widely used for follicular lymphoma. However, there are no established predictors for response or response duration. We analyzed the long-term prognostic relevance of pre-treatment absolute blood counts of lymphocytes with subsets and monocytes in 265 follicular lymphoma patients, uniformly treated with rituximab without chemotherapy, in two Nordic Lymphoma Group trials. There were 265 previously untreated, stage II–IV follicular lymphoma patients with a median follow-up of over 10 years. Absolute B cell counts ≥ median (0.09 × 109/L) were an independent predictor for shorter time to next treatment or death (multivariable analysis P = 0.010). In univariate analysis, absolute monocyte counts ≥ median (0.5 × 109/L) did not correlate with time to next treatment or death, but with inferior overall survival (P = 0.034). Absolute T cell or T cell subset counts were not predictive for outcome. High absolute B cell counts, possibly reflecting circulating lymphoma cells, have an unfavorable impact on time to next treatment or death in patients treated with rituximab without chemotherapy.

Diffuse large B-cell lymphoma (DLBCL) incidence rises with increasing age. Rituximab-anthracycline-based regimens offer a potential cure but also risks of adverse events, especially in the elderly. Using Swedish registers, we conducted a nationwide, population-based study of DLBCL in the very elderly. We obtained information on clinical characteristics, residence, comorbidity, therapy and survival for the 1194 patients aged ≥80 years diagnosed in Sweden 2007-2014. To address selection bias, we also investigated treatment differences between Sweden's Healthcare Regions and whether there were survival differences between the Regions. The 2-year overall and relative survivals were better in patients aged ≥80 years given treatment with curative intent (54%; 64%) than low-intensity (26%; 33%), or palliative treatment (6%; 7%). The fraction of patients treated with curative intent varied between the Healthcare Regions (45-76%). Survival was significantly inferior in Regions with few patients treated with curative intent (multivariable hazard ratio 1.3, 95% confidence interval 1.1-1.6). When treatment intensity and Regions competed, Regions were no longer independent, suggesting that Regional survival differences are due to therapeutic differences. Furthermore, we found that the age-adjusted International Prognostic Index was independently associated with survival. We conclude that patients aged ≥80 years with DLBCL appear to benefit from rituximab-anthracycline-based treatment given with curative intent.

Patients with high-risk aggressive B-cell lymphoma exhibit poor survival after R-CHOP. More intensive regimens yield higher rates of remission but also of complication. We investigated all 401 patients 70 years with high-risk (age-adjusted [aa] international prognostic index [IPI] ≥2, extranodal, or bulky) aggressive B-cell lymphoma hospitalized at Karolinska for urgent start of immunochemotherapy (129 R-Hyper-CVAD; 261 R-CHOP/R-CHOEP). Patients showed IPI 3-5 (70%), WHO PS ≥2 (49%), bulky disease (70%), extranodal (75%) and CNS (8%) involvement. Five-year overall/progression-free survival (OS/PFS) was better in patients who started R-Hyper-CVAD (84%/77%) compared with R-CHOP/R-CHOEP (66%/55%). Differences were independent in multivariable analysis, seen in all patient categories, and accentuated in extreme high-risk disease: R-Hyper-CVAD vs. R-CHOP/R-CHOEP showed 5-year PFS 69% vs.40% in aaIPI 3 and 88% vs. 38% in CNS involvement. For validation, survival was compared between the two Karolinska sites and calendar periods. Survival was superior 2006-2010 at the site that introduced R-Hyper-CVAD/R-MA 2006, identical at both sites 2011-2017 after the other site adopted R-Hyper-CVAD/R-MA 2011, and excellent 2018-2020 when R-Hyper-CVAD/R-MA use increased to 75% of patients. Despite considerable toxicity, also patients aged 61-69 years showed better survival with R-Hyper-CVAD/R-MA. This is the largest single-centre series of patients treated with R-Hyper-CVAD/R-MA, showing favourable outcome in high-risk aggressive B-cell lymphoma.

SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase (dNTPase) that restricts viral replication in infected cells and limits the sensitivity to cytarabine by hydrolysing its active metabolite, as recently shown in acute myeloid leukemia. Cytarabine is an essential component in the Nordic mantle cell lymphoma protocols (MCL2 and MCL3) for induction and high-dose chemotherapy treatment before autologous stem cell transplantation for younger patients with mantle cell lymphoma (MCL). We here investigated the expression of SAMHD1 in a population-based cohort of MCL (N = 150). SAMHD1 was highly variably expressed in MCL (range, 0.4% to 100% of positive tumor cells). Cases with blastoid/pleomorphic morphology had higher SAMHD1 expression (P = 0.028) and SAMHD1 was also correlated to tumor cell proliferation (P = 0.016). SAMHD1 expression showed moderate correlation to the expression of the transcriptional regulator SOX11 (P = 0.036) but genetic silencing of SOX11 and SAMHD1 by siRNA in MCL cell lines did not suggest mutual regulation. We hypothesized that expression of SAMHD1 could predict short time to progression in patients treated with Cytarabine as part of high-dose chemotherapy. Despite the correlation with known biological adverse prognostic factors, neither low or high SAMHD1 expression correlated to PFS or OS in patients treated according to the Nordic MCL2 or MCL3 protocols (N = 158).

The SAKK 35/10 phase 2 trial, developed by the Swiss Group for Clinical Cancer Research and the Nordic Lymphoma Group, compared the activity of rituximab vs rituximab plus lenalidomide in untreated follicular lymphoma patients in need of systemic therapy. Patients were randomized to rituximab (375 mg/m2 IV on day 1 of weeks 1-4 and repeated during weeks 12-15 in responding patients) or rituximab (same schedule) in combination with lenalidomide (15 mg orally daily for 18 weeks). Primary end point was complete response (CR)/unconfirmed CR (CRu) rate at 6 months. In total, 77 patients were allocated to rituximab monotherapy and 77 to the combination (47% poor-risk Follicular Lymphoma International Prognostic Index score in each arm). A significantly higher CR/CRu rate at 6 months was documented in the combination arm by the investigators (36%; 95% confidence interval [CI], 26%-48% vs 25%; 95% CI, 16%-36%) and confirmed by an independent response review of computed tomography scans only (61%; 95% CI, 49%-72% vs 36%; 95% CI, 26%-48%). After a median follow-up of 4 years, significantly higher 30-month CR/CRu rates and longer progression-free survival (PFS) and time to next treatment (TTNT) were observed for the combination. Overall survival (OS) rates were similar in both arms (≥90%). Toxicity grade ≥3 was more common in the combination arm (56% vs 22% of patients), mainly represented by neutropenia (23% vs 7%). Addition of lenalidomide to rituximab significantly improved CR/CRu rates, PFS, and TTNT, with expected higher, but manageable toxicity. The excellent OS in both arms suggests that chemotherapy-free strategies should be further explored. This trial was registered at www.clinicaltrials.gov as #NCT01307605.

Background Autologous stem-cell transplantation (ASCT) is a common treatment for lymphoma but it has some mortality. Methods All 433 lymphoma patients who underwent ASCT for lymphoma at Karolinska Huddinge 1994–2016 were investigated, including CD34+ cell amounts, medications, infectious and other complications, intensive care, longitudinal laboratory values, and secondary myeloid neoplasia. Results The 100-day non-relapse and overall mortalities were 5.6% and 7.2%. Stem-cell harvests

Mantle cell lymphoma (MCL), a malignancy of B-lymphocytes, has a poor prognosis. It is thus necessary to improve the understanding of the pathobiology of MCL and identify factors contributing to its aggressiveness. Our studies, based on Affymetrix data from 17 MCL biopsies, real-time quantitative polymerase chain reaction data from 18 sorted primary MCL cells and 108 MCL biopsies compared to non-malignant tissue, reveals that GNAZ expression predicts poor clinical outcome of MCL patients (Cox regression, P = 0·014) and lymphocytosis (Mann-Whitney, P = 0·011). We show that GNAZ translates to Gαz protein - a signalling molecule within the G-protein coupled receptor network. Our findings suggest that GNAZ/Gαz contribute to the MCL pathobiology.

We performed a national population-based study of all patients diagnosed with diffuse large B-cell lymphoma (DLBCL) in Sweden in 2007–2014 to assess treatment intent and risk of relapsed/refractory disease, including central nervous system (CNS) relapse, in the presence of competing risks. Overall, 84% of patients started treatment with curative intent (anthracycline-based) (n = 3550, median age 69 years), whereas 14% did not (n = 594, median age 84 years) (for 2% the intent was uncertain). Patients treated with curative intent had a 5-year OS of 65.3% (95% CI: 63.7–66.9). The median OS among non-curatively treated patients was 2.9 months. The 5-year cumulative incidence of relapsed/refractory disease in curative patients was 23.1% (95% CI: 21.7–24.6, n = 847). The 2-year cumulative incidence of CNS relapse was 3.0% (95% CI: 2.5–3.6, n = 118) overall, and 8.0% (95% CI: 6.0–10.6, n = 48) among patients with high CNS-IPI (4–6), when considering other relapse locations and death as competing events. The incidence of relapsed/refractory DLBCL overall and in the CNS was lower than in previous reports, still one in seven patients was not considered fit enough to start standard immunochemotherapy at diagnosis. These results are important for quantification of groups of DLBCL patients with poor prognosis requiring completely different types of interventions.

Mechanisms for late-onset neutropenia (LON) after rituximab treatment are poorly defined both for non-Hodgkin lymphoma (NHL) and for autoimmune disorders. We performed a case–control analysis of a prospective cohort of 169 evaluable consecutive rituximab-treated NHL patients to assess cytokines involved in neutro- and lymphopoiesis (G-CSF, SDF1, BAFF, APRIL) and inflammation (CRP) as possible LON mechanisms. Fifteen patients (9%) developed LON (peripheral blood /PB/ absolute neutrophil counts /ANC/

Background Chimeric antigen-receptor T-cell and bispecific antibody therapies will likely necessitate a reconsideration of the role of autologous stem-cell transplantation (ASCT) in lymphoma. Patients who are likely to profit from ASCT need to be better identified. Methods Here, we investigated the value of positron emission tomography/computerized tomography (PET/CT) before ASCT. All 521 patients transplanted for lymphoma 1994–2019 at Karolinska (497 conditioned with BEAM) were included. Results Outcome improved over three calendar periods 1994–2004, 2005–2014, 2015–2019 (2-year overall survival [OS]: 66, 73, 83%; P = 0.018). Non-relapse mortality (NRM) at 100 days over the three periods were 9.8, 3.9, 2.9%, respectively. The OS improvement between 1994 and 2004 and 2005–2014 was due to lower NRM (P = 0.027), but the large OS advance from 2015 was not accompanied by a significant reduction in NRM (P = 0.6). The fraction of PET/CT as pre-ASCT assessment also increased over time: 1994–2004, 2%; 2005–2014, 24%; 2015–2019, 60% (P P = 0.0003), also in the subpopulations of aggressive B-cell (P = 0.004) and peripheral T-cell (P = 0.024) lymphomas. Two-year OS and progression-free survival (OS/PFS) for patients in PET/CT-CR were in relapsed/refractory aggressive B-cell lymphoma 87%/75% and peripheral T-cell lymphoma 91%/78%. The corresponding figures in PET/CT-PR were 43%/44 and 33%/33%. Patients with solitary PET/CT-positive lesions showed acceptable outcome with ASCT followed by local irradiation (2-year OS/PFS 80%/60%). CT was less discriminative: 2-year OS/PFS: CT-CR, 76%/66%; CT-PR, 62%/51%. Outcome was inferior after BEAC compared with BEAM conditioning. Conclusions We conclude that the improved outcome reflects better, PET/CT-informed, identification of patients who should proceed to ASCT. The excellent survival of patients in PET/CT-CR indicates that ASCT should remain part of standard therapy for lymphoma.

Current prognostic variables can only partly explain the large outcome heterogeneity in diffuse large B cell lymphoma (DLBCL). We aimed to investigate the utility of systems-level protein and immune repertoire profiling for outcome prognostication in DLBCL.In this retrospective study, we used proximity extension assay technology to quantify 81 immune-related proteins in serum or plasma in 2 independent cohorts in a total 111 DLBCL patients. Protein levels were assessed before and after treatment with rituximab and chemotherapy, and the patients were compared with 19 age- and sex-matched healthy blood donors. In a subset of the patients, we performed a broad mass cytometric characterization of immune cell repertoires in peripheral blood.Patients displayed large deviations in protein profiles compared with healthy controls. Development of a systemic protein deviation (SPD) score provided a 4-protein-based metric that reflected the overall degree of protein deviations compared with age- and sex-matched healthy blood donors. The SPD score identified patients with very poor overall survival in both cohorts and correlated with increased frequencies of peripheral blood PD-1Our results show that a simple metric based on measurement of a small set of serum or plasma proteins can be used to probe systemic immune changes associated with poor survival in DLBCL. This finding warrants further investigation in larger, prospective studies to establish a clinical prognostic biomarker.

Bruton tyrosine kinase (BTK) inhibition is an effective treatment approach for patients with Waldenström macroglobulinemia (WM). The phase 3 ASPEN study compared the efficacy and safety of ibrutinib, a first-generation BTK inhibitor, with zanubrutinib, a novel highly selective BTK inhibitor, in patients with WM. Patients with MYD88L265P disease were randomly assigned 1:1 to treatment with ibrutinib or zanubrutinib. The primary end point was the proportion of patients achieving a complete response (CR) or a very good partial response (VGPR) by independent review. Key secondary end points included major response rate (MRR), progression-free survival (PFS), duration of response (DOR), disease burden, and safety. A total of 201 patients were randomized, and 199 received ≥1 dose of study treatment. No patient achieved a CR. Twenty-nine (28%) zanubrutinib patients and 19 (19%) ibrutinib patients achieved a VGPR, a nonstatistically significant difference (P = .09). MRRs were 77% and 78%, respectively. Median DOR and PFS were not reached; 84% and 85% of ibrutinib and zanubrutinib patients were progression free at 18 months. Atrial fibrillation, contusion, diarrhea, peripheral edema, hemorrhage, muscle spasms, and pneumonia, as well as adverse events leading to treatment discontinuation, were less common among zanubrutinib recipients. Incidence of neutropenia was higher with zanubrutinib, although grade ≥3 infection rates were similar in both arms (1.2 and 1.1 events per 100 person-months). These results demonstrate that zanubrutinib and ibrutinib are highly effective in the treatment of WM, but zanubrutinib treatment was associated with a trend toward better response quality and less toxicity, particularly cardiovascular toxicity.

Plerixafor + granulocyte-colony stimulating factor (G-CSF) is administered to patients with lymphoma who are poor mobilizers of hematopoietic stem cells (HSCs) in Europe. This international, multicenter, non-interventional registry study (NCT01362972) evaluated long-term follow-up of patients with lymphoma who received plerixafor for HSC mobilization versus other mobilization methods. Propensity score matching was conducted to balance baseline characteristics between comparison groups. The following mobilization regimens were compared: G-CSF + plerixafor (G + P) versus G-CSF alone; G + P versus G-CSF + chemotherapy (G + C); and G-CSF + plerixafor + chemotherapy (G + P + C) versus G + C. The primary outcomes were progression-free survival (PFS), overall survival (OS), and cumulative incidence of relapse (CIR). Overall, 313/3749 (8.3%) eligible patients were mobilized with plerixafor-containing regimens. After propensity score matching, 70 versus 36 patients were matched in the G + P versus G-CSF alone cohort, 124 versus 124 in the G + P versus G + C cohort, and 130 versus 130 in the G + P + C versus G + C cohort. For both PFS and OS, the upper bound of confidence interval for the hazard ratio was >1.3 for all comparisons, implying that non-inferiority was not demonstrated. No major differences in PFS, OS, and CIR were observed between the plerixafor and comparison groups.

Follicular lymphoma (FL) is a heterogeneous disease; therefore, reliable prognostic tools are needed to plan treatment strategies. The FL International Prognostic Index (FLIPI) was developed before the rituximab era, while the PRIMA-PI was built on rituximab chemotherapy. Our objective was to evaluate these two prognostic tools in a cohort of 291 patients with FL treated in two prospective randomised Nordic Lymphoma Group trials with rituximab +/- interferon. All patients had symptomatic/progressive disease and were previously untreated. The PRIMA-PI was prognostic for both time to treatment failure (TTF) and overall survival (OS) (log-rank P = 0 center dot 003 and P < 0 center dot 001, respectively). The PRIMA-PI high-risk identified a small group of patients with a very short TTF and OS compared to the low-risk group, with a hazard ratio (HR) of 1 center dot 90 (95% confidence interval [CI] 1 center dot 30-2 center dot 78, P = 0 center dot 001) and HR of 3 center dot 19 (95% CI 1 center dot 75-5 center dot 83, P < 0 center dot 001), respectively. The FLIPI risk groups were prognostic only for OS (log-rank P = 0 center dot 018). The simplified PRIMA-PI was valid in our FL cohort with first-line rituximab-containing chemo-free therapy and shows an improved risk stratification compared to the FLIPI, especially in patients aged >60 years. Patients in the PRIMA-PI high-risk group should be considered for alternative therapies.

Purpose: To evaluate the safety, efficacy, and immunobiological correlates of allogeneic NK-cell–based therapy in primary chemotherapy-refractory or relapsed high-risk myelodysplastic syndrome (MDS), secondary AML (MDS/AML), and de novo AML patients. Experimental Design: Sixteen patients received fludarabine/cyclophosphamide conditioning combined with total lymphoid irradiation followed by adoptive immunotherapy with IL2–activated haploidentical NK cells. Results: NK-cell infusions were well-tolerated, with only transient adverse events observed in the 16 patients. Six patients achieved objective responses with complete remission (CR), marrow CR, or partial remission (PR). Five patients proceeded to allogeneic hematopoietic stem cell transplantation (HSCT). Three patients are still free from disease >3 years after treatment. All evaluable patients with objective responses (5/5 evaluable) had detectable donor NK cells at days 7/14 following infusion and displayed reduction of tumor cell clones, some of which carried poor prognosis mutations. Residual lin−CD34+CD123+CD45RA+ blast cells in responders had increased total HLA class I and HLA-E expression. Responding patients displayed less pronounced activation of CD8+ T cells and lower levels of inflammatory cytokines following NK-cell infusion. Intriguingly, despite omission of systemic IL2, all patients displayed increased frequencies of activated Ki-67+CD127−FoxP3+CD25hiCD4+ Treg cells of recipient origin following NK-cell therapy. Conclusions: Overall, this study suggests that high-risk MDS is responsive to NK-cell therapy and supports the use of haploidentical NK-cell infusions as a bridge to HSCT in refractory patients. Objective clinical responses and reduction of high-risk clones were associated with detectable donor-derived NK cells, immunoediting of residual blast cells, and less pronounced host immune activation. Clin Cancer Res; 24(8); 1834–44. ©2018 AACR.

INTRODUCTION Patients with high-risk aggressive B-cell lymphoma exhibit poor survival after R-CHOP-like immunochemotherapy. More intensive regimens yield higher rates of remission but also of complication, which have hindered their use, particularly in older patients. At Karolinska, the standard intensive regimen has been R-Hyper-CVAD/R-MA for patients with high-risk characteristics, such as high age-adjusted international prognostic index (aaIPI) and extranodal disease. METHODS In this analysis, high-risk disease was defined as aaIPI ≥ 2 or any extranodal involvement. We examined Karolinska's 136 patients who received at least one cycle of R-Hyper-CVAD/R-MA in first-line therapy for high-risk disease, excluding Burkitt, transformed, and primary CNS lymphoma. Patients were diagnosed between 2006 and 2020; 89 were diffuse large B-cell lymphoma, 23 high-grade B-cell lymphoma, 17 primary mediastinal B-cell lymphoma, 4 T cell/histiocyte-rich B-cell lymphoma, 2 aggressive B-cell lymphoma unspecified, 1 lymphomatoid granulomatosis grade 3. For outcome, we investigated progression-free survival (PFS). RESULTS In this cohort of 136 patients with high-risk disease treated with at least one cycle of R-Hyper-CVAD/R-MA, the median age was 52 years (range, 19-69); 36 patients (26%) were 61-69 years old. Lactate dehydrogenase was elevated in 92%, stage III-IV disease was seen in 93%, WHO performance status ≥2 in 49%, aaIPI = 3 in 38%, extranodal disease in 30%, CNS involvement in 17%, and Charlson comorbidity index ≥2 in 11%. At 5 years, the PFS in all patients was 72% and in the 50 patients with aaIPI = 3, 66% (Figure 1). In patients ≤60 years old, 5-year PFS was 76% (aaIPI = 3, 69%). In patients 61-69 years, the 5-year PFS was 58% (aaIPI = 3, 59%). Six out of 136 patients (4%) died from toxicity during induction therapy (3/6 were 61-69 years old). CONCLUSIONS This is to our knowledge the largest published single-center series of patients treated with R-Hyper-CVAD/R-MA for high-risk aggressive B-cell lymphoma. Outcome in these patients aged 19-69 years was excellent, with 5-year PFS 72%. Particularly patients with aaIPI = 3 showed rather good outcome with 5-year PFS 66%. For comparison, in Sweden the 5-year overall survival of R-CHOP-treated patients ≤60 years with aaIPI = 3 is 40% (Melén CM et al. Brit J Haematol. 614-622. 2016). We will continue to explore R-Hyper-CVAD/R-MA as primary therapy for high-risk aggressive B-cell lymphoma. Figure 1 Figure 1. Disclosures Wahlin: Gilead Sciences: Research Funding; Roche: Consultancy, Research Funding.

Background: Patients (pts) with relapsed or refractory (R/R) follicular lymphoma (FL) develop increasingly aggressive disease and are at increased risk for histologic transformation, death, or both. The combination of rituximab and lenalidomide (R 2) is a highly effective therapy for pts with R/R FL, but most pts eventually relapse, and better treatment options are needed. Epcoritamab (DuoBody ®-CD3×CD20) is a subcutaneously administered bispecific antibody that binds to CD3 on T cells and CD20 on B cells and induces conditional T-cell-mediated killing of malignant B cells. Single-agent epcoritamab demonstrated manageable safety and substantial antitumor activity in pts with heavily pretreated B-cell non-Hodgkin lymphoma (NHL) in the phase 1/2 EPCORE NHL-1 trial (NCT03625037). Among heavily pretreated pts with R/R FL (median, 5 prior lines of therapy) treated with epcoritamab (dose, 0.76-48 mg), the overall response rate was 90% (9/10), with 50% (5/10) achieving complete response (Hutchings, Lancet, in press). Treatment with R 2 has immunomodulatory properties that may potentiate the activity of epcoritamab, suggesting that combining R 2 with epcoritamab may be beneficial. The encouraging data from the EPCORE NHL-1 trial supported initiation of the EPCORE NHL-2 trial (NCT04663347), a phase 1/2 trial evaluating epcoritamab in combination with various standard of care therapies in pts with B-cell NHL. Herein, we present preliminary results from arm 2 of this trial, which is evaluating epcoritamab in combination with R 2 in pts with R/R FL. Methods: Adults with histologically confirmed R/R CD20+ FL received epcoritamab in a dose-escalation phase followed by an expansion phase at the recommended phase 2 dose in combination with R 2 for 12 cycles (28 days/cycle). Step-up dosing and corticosteroids during cycle 1 were used to mitigate cytokine release syndrome (CRS). Responses were evaluated by position emission tomography-computed tomography per the 2014 Lugano classification criteria. Results: As of June 29, 2021, 16 pts were treated with the combination of epcoritamab + R 2 (3 pts treated with epcoritamab 24 mg and 13 with 48 mg). Five pts completed at least 6 weeks of therapy and were evaluable for efficacy. A median of 3 cycles per pt have been administered. Fourteen (88%) pts remain on treatment. Median age was 68 years (range, 52-81), 10 (63%) pts were female, and 11 (69%) had 1 prior line of therapy (range in all 16 pts, 1-3 prior lines). All pts received prior immunochemotherapy, and 6 (38%) had disease progression ≤2 years after initial treatment (POD24). CRS occurred in 31% of pts (5/16) and all cases were of grade 1/2. The median time to onset of CRS was 15 days (study day 16; range, 5-16) and median time to resolution was 2 days; no pt required tocilizumab. Other adverse events (AEs) reported in >15% of pts were injection-site reaction (25%; 4/16), constipation (19%; 3/16), cough (19%; 3/16), diarrhea (19%; 3/16), and stomatitis (19%; 3/16), all grade 1/2. No immune effector cell-associated neurotoxicity syndrome events or fatal AEs were observed. Five (31%) pts required hospitalization due to 6 serious AEs (grade 1 CRS related to epcoritamab in 3 pts; unrelated grade 2 mania in 1 pt; unrelated grade 3 pneumonia in 1 pt; and unrelated grade 3 atrial flutter). All 5 response-evaluable pts achieved an objective response by week 7, with 4 achieving complete metabolic response. All 5 responders had stage IV disease at baseline, 3 had an FL International Prognostic Index of 4/5, 3 had received >2 prior lines of therapy, and 2 had POD24 with first-line therapy. Conclusions: These data from a small population of pts suggest that epcoritamab can be safely combined with R 2 with a manageable toxicity profile, with no new safety signals or unexpected AEs. The novel chemotherapy-free combination showed encouraging preliminary activity with early responses in all evaluable pts by week 7, including a majority of pts with high-risk features. Enrollment is ongoing. Additional data will be presented. Disclosures Linton: Blood Cancer UK: Research Funding; Genmab: Consultancy, Research Funding; Roche: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Beigene: Research Funding; Aptitude Health: Honoraria, Speakers Bureau; Hartley Taylor: Honoraria, Speakers Bureau; Kite: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Roy Castle Lung Cancer Foundation: Research Funding; Janssen: Other: Travel support. Wahlin: Roche: Consultancy, Research Funding; Gilead Sciences: Research Funding. Leepä: MSD: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; CHO Pharma USA: Consultancy; Orion: Consultancy; Genmab: Research Funding; University of Helsinki and Helsinki University Hospital: Current Employment; Takeda: Research Funding; Bayer: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Nordic Nanovector: Research Funding; Finnish Cancer Organizations: Membership on an entity's Board of Directors or advisory committees. Morschhauser: Chugai: Honoraria; Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genentech, Inc.: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; Incyte: Membership on an entity's Board of Directors or advisory committees; AstraZenenca: Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genmab: Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Speakers Bureau; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Servier: Consultancy; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Elliot: Genmab: Current Employment, Patents & Royalties: P158-US-PSP3 . Liu: Genmab: Current Employment. Cota Stirner: AbbVie: Current Employment. Abbas: Genmab: Current Employment. Falchi: Abbvie: Consultancy, Research Funding; Genetech: Research Funding; Roche: Research Funding; Genmab: Consultancy, Research Funding.

Background: Marginal zone lymphoma (MZL) is the third most common lymphoma in Western countries, accounting for 8-12% of non-Hodgkin lymphoma (Delinger NM. Cancer Manag Res. 2018;10:315-24). MZL is categorized into nodal, extranodal, and splenic subtypes. While the relative 5-year survival rate for patients (pts) with MZL is 84.4% (Olszewski AJ, Castillo JJ. Cancer. 2013;119:629-38), pts often experience relapse or refractory (R/R) disease. Parsaclisib is a potent, highly selective, next-generation inhibitor of phosphatidylinositol 3-kinase (PI3K)δ. Here we report results of the primary analysis of the cohort of Bruton's tyrosine kinase (BTK) inhibitor (BTKi)-naive pts with R/R MZL treated with parsaclisib monotherapy in the open-label, phase 2 study CITADEL-204 (NCT03144674, EudraCT 2017-000970-12). Methods: Pts ≥18 years of age, with histologically confirmed MZL, prior receipt of ≥1 line of systemic therapy including anti-CD20 treatment, and either disease progression or inadequate response to most recent regimen were eligible. Pts had an Eastern Cooperative Oncology Group performance status (ECOG PS) ≤2, radiologically measurable lymphadenopathy, lymphoid malignancy (extranodal), or histologically confirmed bone marrow infiltration (splenic). The study enrolled 2 cohorts: pts who received prior treatment with ibrutinib (cohort 1, N=10) or pts naive to BTKi therapy (cohort 2, N=100). Only data from cohort 2 are presented in this abstract. Pts were allocated to receive parsaclisib 20 mg once daily (QD) for 8 weeks followed by either 20 mg once weekly (weekly-dosing group [WG]) or 2.5 mg QD (daily-dosing group [DG]). Pts received prophylaxis for Pneumocystis jirovecii pneumonia during the study. The primary endpoint was objective response rate (ORR) as assessed by an independent review committee (IRC); secondary endpoints were duration of response (DOR), complete response rate (CRR), progression-free survival (PFS), overall survival (OS), and safety and tolerability. All radiology-based endpoints were evaluated by an IRC. Results: At data cutoff for the primary analysis (Jan 15, 2021), 100 pts with MZL enrolled in cohort 2 (nodal 31.0%, extranodal 34.0%, and splenic 35.0%) had been treated (WG, N=28; DG, N=72). Median (range) age was 71.0 (35-95) years, 53.0% were male, and 95.0% had ECOG PS ≤1. 49.0% of pts had received 1 line, 31.0% received 2 lines, and 20.0% received ≥3 lines of prior systemic therapy (median [range], 2.0 [1-8]); 46.0% of pts had relapsed disease and 49.0% were refractory to their most recent prior therapy. 65.0% of pts had discontinued treatment, primarily due to adverse events (29.0%) or progressive disease (28.0%). The median (range) duration of treatment and follow-up from first dose to data cutoff were 13.4 (0.4-30.9) and 22.8 (11.9-37.0) months for all pts (N=100), and 11.6 (0.4-30.9) and 21.0 (11.9-37.0) months for the DG (N=72), respectively. The ORR (95% CI) was 58.0% (47.7-67.8) for all pts and 58.3% (46.1-69.8) for the DG (Table 1); CRR (95% CI) was 6.0% (2.2-12.6) for all pts and 4.2% (0.9-11.7) for the DG. Among all treated pts who achieved complete or partial response, 65.5% of responses occurred at the first disease assessment (median time to response, 8.1 weeks); median DOR (95% CI) was 12.2 (8.1-17.5) months for all pts and the DG. Median PFS (95% CI) was 16.5 (13.5-19.6) and 16.5 (11.5-20.6) months for all pts and the DG, respectively. Median OS was not reached. Among 100 pts treated in cohort 2, treatment-emergent adverse events (TEAEs) occurred in 96.0% of pts (grade ≥3 in 63.0%). The most common TEAEs were diarrhea (47.0%) and cough (23.0%), and the most common grade ≥3 TEAEs included diarrhea (12.0%), neutropenia and pneumonia (9.0% each), and colitis (7.0%). TEAEs leading to dose interruption or dose reduction occurred in 56.0% and 16.0% of pts, respectively. TEAEs led to treatment discontinuation in 29.0% of pts, the most common were diarrhea (9.0%) and colitis (5.0%). Serious TEAEs were experienced by 47.0% of pts overall, the most common was pneumonia (9.0%). 6.0% of pts experienced fatal TEAEs including febrile neutropenia and sepsis (1 pt each) that were considered treatment-related. Conclusion: Pts with R/R MZL demonstrated a rapid and durable clinical response to parsaclisib monotherapy. Treatment was generally well tolerated, and the safety profile was manageable. Results suggest parsaclisib may be a potential treatment option for R/R MZL. Figure 1 Figure 1. Disclosures Phillips: AstraZeneca: Consultancy; ADCT, BeiGene, Bristol Myers Squibb, Cardinal Health, Incyte, Karyopharm, Morphosys, Pharmacyclics, Seattle Genetics: Consultancy; Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Bayer: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Incyte: Consultancy, Other: received travel expenses from Incyte, Research Funding. Avigdor: Pfizer: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; BMS: Research Funding; Janssen: Research Funding; Takeda: Consultancy, Honoraria. Gurion: JC Health CARE; Roche: Honoraria; Medison; Gilead Sciences; Takeda Pharmaceuticals: Consultancy. Corradini: KiowaKirin; Incyte; Daiichi Sankyo; Janssen; F. Hoffman-La Roche; Kite; Servier: Consultancy; AbbVie, ADC Theraputics, Amgen, Celgene, Daiichi Sankyo, Gilead/Kite, GSK, Incyte, Janssen, KyowaKirin, Nerviano Medical Science, Novartis, Roche, Sanofi, Takeda: Honoraria; Amgen; Takeda; AbbVie: Consultancy, Honoraria, Other: Travel and accommodations; Novartis; Gilead; Celgene: Consultancy, Other: Travel and accommodations; BMS: Other: Travel and accommodation; Sanofi: Consultancy, Honoraria; Incyte: Consultancy; AbbVie, ADC Theraputics, Amgen, Celgene, Daiichi Sankyo, Gilead/Kite, GSK, Incyte, Janssen, KyowaKirin, Nerviano Medical Science, Novartis, Roche, Sanofi, Takeda: Consultancy; Novartis, Janssen, Celgene, BMS, Takeda, Gilead/Kite, Amgen, AbbVie: Other: travel and accomodations. Mehta: Seattle Genetics; Incyte; TG Therapeutics: Consultancy; Seattle Genetics; Incyte; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Affirmed; Kite/Gilead; Roche-Genetech; Celgene/BMS; Oncotartis; Innate Pharmaceuticals; Seattle Genetics; Incyte; Takeda; Fortyseven Inc/Gilead; TG Therapeutics; Merck; Juno Pharmaceuticals/Bristol Myers Squibb: Research Funding. Lossos: NIH grants: Research Funding; Verastem: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Lymphoma Research Foundation: Membership on an entity's Board of Directors or advisory committees; University of Miami: Current Employment; NCI: Research Funding; Stanford University: Patents & Royalties; Seattle Genetics: Consultancy. Zinzani: Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ImmuneDesign: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BeiGene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck Sharp & Dohme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Kyowa Kirin: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Thieblemont: Cellectis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Kyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Gilead Sciences: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Hospira: Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Bristol Myers Squibb/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses , Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Bayer: Honoraria; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses . Jurczak: AbbVie, AstraZeneca, Bayer, BeiGene, Celtrion, Celgene, Debbiopharm, Epizyme, Incyte, Janssen, Loxo Oncology, Merck, Mei Pharma, Morphosys, Novo Nordisk, Roche, Sandoz, Takeda, TG Therapeutics, Pharmacyclics, Affirmed, Gilead Sciences, Nordic Nanovecto: Research Funding; AstraZeneca, BeiGene, Janssen, Loxo Oncology, Sandoz, Roche: Membership on an entity's Board of Directors or advisory committees; Maria Sklodowska-Curie National Research Institute of Oncology: Current Employment; Jagiellonian University: Ended employment in the past 24 months; European Medicines Agency, Sandoz-Novartis, Janssen China R&D, BeiGene, Epizyme, Acerta, AstraZeneca: Consultancy. Zheng: Incyte Corporation: Current Employment, Current equity holder in publicly-traded company. Rappold: Incyte: Current Employment, Current equity holder in publicly-traded company. Zhao: Incyte: Current Employment, Current equity holder in publicly-traded company. Johnson: Epizyme: Consultancy, Research Funding; Boehringer Ingelheim: Consultancy; Bristol-Myers: Honoraria; Celgene: Honoraria; Genmab: Honoraria; Incyte: Honoraria; Kite Pharma: Honoraria; Kymera: Honoraria; Morphosys: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Oncimmune: Consultancy; Janssen: Consultancy. OffLabel Disclosure: Investigational PI3Kdelta inhibitor (parsaclisib) for patients with MZL

Background: CD20 antibody plus alkylator and/or anthracycline based immunochemotherapy (IC) is a standard frontline therapy for patients with follicular lymphoma (FL) with 10-year event-free survival (EFS) and overall survival (OS) rates of approximately 50% and 80% respectively in long-term follow-up of clinical trials. Currently available clinical prognostic indices for FL have been designed using PFS and OS endpoints. Early events, commonly defined as progression of disease within 24 months (POD24) or early transformation to a more aggressive histology, are associated with inferior outcomes and increased risk of death due to refractory FL. Timely identification of the minority of patients with elevated mortality risk might enhance clinical management and research strategies. The FLIPI24 Consortium was created to develop a clinical prognostic index using early events as the primary endpoint. We report the outcomes for the pooled cohort and investigate the implications of therapy patterns on potential model development. Methods: Individual patient data were pooled and harmonized from 11 prospective observational cohorts from Europe, North America, and Australia. Patients who were diagnosed with grades 1-3A FL and initiated frontline IC were eligible. EFS was defined as time from start of IC to progression, relapse, retreatment (2nd line), histologic transformation, or death due to any cause. Early events were defined using status at 24 months from start of IC. OS was defined as time from start of IC to death due to any cause. Kaplan Meier curves and Cox proportional hazards models were used to evaluate outcomes by clinical features and therapy types. Results: 9006 patients were abstracted and harmonized, 6111 patients initiated frontline IC between 2002 and 2018 and were included in this analysis. Median age at diagnosis was 61 years (IQR 52-69) and 50% were male. Complete FLIPI data were available in 5637 patients (92%) and 46%, 32%, and 22% were low, intermediate, and high risk, respectively. IC type was 3079 R-CHOP or like (50%) , 1529 R-CVP or like (25%), 918 R-bendamustine (B-R) or like (15%), and 585 fludarabine or other alkylator based IC (10%); 3187 received CD20 antibody maintenance (52%). Patients receiving R-CHOP were younger, more frequently grade 3A, and more frequently had elevated LDH; differences in other characteristics by IC type were not clinically meaningful. At median follow-up of 42 months (IQR 17-72), 2647 patients (43%) had an event (any) and 1494 patients (25%) died. Median survival after an early (non-death) event was 49 months (95% CI: 41-58); 5-year OS was 46% (95% CI: 43-49) compared to 89% (95% CI: 88-90) in patients without POD24. Across all IC types, EFS estimates at 2 and 10 years from start of IC were 80% (95% CI:79-81) and 49% (95% CI:48-51) and OS estimates were 92% (95% CI: 91-92) and 70% (95% CI: 69-72), respectively. FLIPI was highly associated with both EFS (c-statistic=0.61) and OS (c-statistic=0.65) from the initiation of IC (both p Treatment patterns changed significantly over the study timeframe. Use of B-R and/or maintenance increased to 30% and 70% respectively in N=2937 patients treated in 2010-2018 (Era2) compared to Conclusion: EFS and OS from this large pooled analysis of observational cohorts is similar to long-term follow-up of randomized clinical trials in the IC era and support the use of these data for model development. Modeling efforts for early events should adjust for initial IC selection and use of maintenance therapy. Utilization of bendamustine and/or maintenance therapy increased over the study timeframe from 2002-2018, and Era2 was associated with improved EFS but not OS. This cohort provides comprehensive and robust observational data to define clinical predictors in IC treated patients. Figure 1 Figure 1. Disclosures Maurer: Genentech: Research Funding; Morphosys: Membership on an entity's Board of Directors or advisory committees, Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; BMS: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees; Nanostring: Research Funding. Flowers: Janssen: Research Funding; Takeda: Research Funding; National Cancer Institute: Research Funding; Biopharma: Consultancy; BeiGene: Consultancy; Amgen: Research Funding; Celgene: Consultancy, Research Funding; Xencor: Research Funding; Acerta: Research Funding; Bayer: Consultancy, Research Funding; Sanofi: Research Funding; 4D: Research Funding; Adaptimmune: Research Funding; Allogene: Research Funding; EMD: Research Funding; TG Therapeutics: Research Funding; Burroughs Wellcome Fund: Research Funding; Kite: Research Funding; AbbVie: Consultancy, Research Funding; Cellectis: Research Funding; Denovo: Consultancy; Cancer Prevention and Research Institute of Texas: CPRIT Scholar in Cancer Research: Research Funding; Karyopharm: Consultancy; Gilead: Consultancy, Research Funding; Genmab: Consultancy; Epizyme, Inc.: Consultancy; Novartis: Research Funding; Nektar: Research Funding; Morphosys: Research Funding; Iovance: Research Funding; Spectrum: Consultancy; Pfizer: Research Funding; Ziopharm: Research Funding; Guardant: Research Funding; Eastern Cooperative Oncology Group: Research Funding; SeaGen: Consultancy; Pharmacyclics/Janssen: Consultancy; Genentech/Roche: Consultancy, Research Funding; Pharmacyclics: Research Funding. Villa: Janssen: Honoraria; Gilead: Honoraria; AstraZeneca: Honoraria; AbbVie: Honoraria; Seattle Genetics: Honoraria; Celgene: Honoraria; Lundbeck: Honoraria; Roche: Honoraria; NanoString Technologies: Honoraria. Weibull: Jansen-Cilag: Other: part of a research collaboration between Karolinska Institutet and Janssen Pharmaceutica NV for which Karolinska Institutet has received grant support. Ghesquieres: Janssen: Honoraria; Mundipharma: Consultancy, Honoraria; Roche: Consultancy; Celgene: Consultancy, Honoraria; Gilead Science: Consultancy, Honoraria. Kridel: Gilead Sciences: Research Funding. Gandhi: Janssen: Research Funding; Novartis: Honoraria. Cheah: Celgene: Research Funding; TG Therapeutics: Consultancy, Honoraria, Other: advisory; Loxo/Lilly: Consultancy, Honoraria, Other: advisory; AstraZeneca: Consultancy, Honoraria, Other: advisory; AbbVie: Research Funding; Beigene: Consultancy, Honoraria, Other: advisory; Ascentage pharma: Consultancy, Honoraria, Other: advisory; Gilead: Consultancy, Honoraria, Other: advisory; MSD: Consultancy, Honoraria, Other: advisory, Research Funding; Janssen: Consultancy, Honoraria, Other: advisory; Roche: Consultancy, Honoraria, Other: advisory and travel expenses, Research Funding. Hawkes: Gilead: Membership on an entity's Board of Directors or advisory committees; Merck Sharpe Dohme: Membership on an entity's Board of Directors or advisory committees; Antigene: Membership on an entity's Board of Directors or advisory committees; Regeneron: Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squib/Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck KgA: Research Funding; Specialised Therapeutics: Consultancy; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel and accommodation expenses, Research Funding, Speakers Bureau; Janssen: Speakers Bureau. Seymour: Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sunesis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Mei Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees; Morphosys: Honoraria, Membership on an entity's Board of Directors or advisory committees; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Freeman: Amgen: Honoraria; Celgene: Honoraria; Sanofi: Honoraria, Speakers Bureau; Incyte: Honoraria; Abbvie: Honoraria; Teva: Research Funding; Roche: Research Funding; Janssen: Honoraria, Speakers Bureau; Seattle Genetics: Honoraria; Bristol Myers Squibb: Honoraria, Speakers Bureau. Clausen: Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel expences ASH 2019; Gilead: Consultancy, Other: Travel expences 15th ICML ; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Wahlin: Gilead Sciences: Research Funding; Roche: Consultancy, Research Funding. Link: Novartis, Jannsen: Research Funding; Genentech/Roche: Consultancy, Research Funding; MEI: Consultancy. Ekstroem Smedby: Janssen Cilag: Research Funding; Takeda: Consultancy. Sehn: Genmab: Consultancy; Novartis: Consultancy; Debiopharm: Consultancy. Trněný: Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Portola: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; 1st Faculty of Medicine, Charles University, General Hospital in Prague: Current Employment; Celgene: Consultancy; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Amgen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; MorphoSys: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria; Gilead Sciences: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. El-Galaly: ROCHE Ltd: Ended employment in the past 24 months; Abbvie: Other: Speakers fee. Cerhan: Celgene/BMS: Other: Connect Lymphoma Scientific Steering Committee, Research Funding; Regeneron Genetics Center: Other: Research Collaboration; Genentech: Research Funding; NanoString: Research Funding.

Mobilized PBSC are the main source for allogeneic HSCT. We aimed to evaluate factors that affect CD34+ cell yield including the donor's age, gender, BSA, processed blood volume and the method of G-CSF dose calculation. Data from 170 healthy donors were analyzed. The concentration of CD34+ cells in the peripheral blood (PB) and the processed volume of blood were significantly correlated to CD34+ cells yield (P

Purpose: Follicular lymphoma (FL) is generally regarded as an indolent malignancy, yet the clinical outcome is highly variable. In recent years, POD24 (progression of disease within 24 months) has emerged as a potential prognostic marker for overall survival (OS) in FL and other non-Hodgkin lymphomas. The association with survival, however, has mostly been studied in selected clinical trial cohorts and among patients treated with R-CHOP. We aimed to investigate OS by timing of progression and type of primary treatment in a population-based setting in Sweden. Methods: We identified all patients diagnosed with FL in stages II-IV and grade 1-3a between 2007 and 2014, using the population-based Swedish lymphoma register. Data were complemented with information on progression, transformation and second-line treatment through medical charts review up to December 31st, 2017. The analysis covered 4 out of 6 health care regions (75% of all patients diagnosed nationally). The patients were categorized according to type of first-line treatment: R-chemo of any type, R-Benda, R-CHOP (including R-CHOEP), or other (including immunotherapy only). Among patients where it was decided to start first-line treatment within 6 months of diagnosis (and where treatment was started within nine months), POD was defined as either lack of response to first-line therapy (stable [SD] or progressive disease [PD]), or initial response and subsequent relapse/progression/transformation as indication for second-line therapy. To quantify the impact of timing of POD on survival, the five-year OS conditional on either being progression-free (PF) or having experienced POD at different time points during follow-up, was estimated using a flexible parametric illness-death model. Results: Among a total of 970 FL patients, median age at diagnosis was 66 years and patients were followed for a median of 6.4 years (range 0-12 years). The 5-year OS was 75% and progression-free survival was 59%. Six hundred (62%) patients had a first-line treatment within nine months of diagnosis and were hence analyzed further, whereas the remaining 370 (38%) patients were classified as wait-and-watch and were not analyzed further. Among the 600 treated patients, 337 (56%) had R-chemo (R-CHOP or alike (n=210), R-Benda (n=97), other (n=30)), and 263 (44%) received non-R-chemo treatment (mainly R-monotherapy, radiotherapy only, or R-lenalidomide). Patients who received R-Benda were on average older than the other groups. Among patients treated with R-chemo, those who stayed progression-free had a 5-year conditional OS above 75% regardless of PF time point. For patients who progressed, the 5-year conditional OS improved as time point of POD was prolonged (Fig 1a, left panel). Early POD (within 12-24 months) was associated with a particularly poor prognosis (5-year conditional OS below 55%). The OS improvement over time of POD was especially pronounced among R-Benda treated patients (Fig 1b, right panel). Among patients receiving non-R-chemo treatments, early POD was associated with a slightly worse 5-year OS but differences between POD and PF patients were less marked (Fig 1a, right panel). Conclusion: This population-based study of Swedish stage II-IV FL patients shows that among immunochemotherapy-treated patients, progression of disease was always associated with worse survival in comparison to progression-free patients regardless of timing of progression. This reduction in survival was more pronounced the earlier the progression (as described by others). Interestingly, among patients selected for milder non-immunochemotherapy-based treatments, progression of disease did not have a strong effect on survival. Disclosures Weibull: Janssen Cilag: Research Funding. Wahlin:Gilead Sciences: Research Funding; Roche: Consultancy, Research Funding. Smedby:Takeda: Research Funding; Janssen: Research Funding; Celgene: Consultancy.

Background: Marginal zone lymphoma (MZL) is a clinically heterogeneous, indolent, non-Hodgkin lymphoma (NHL) with 3 subtypes classified as extranodal, nodal, and splenic MZL. Parsaclisib, a potent, highly-selective, next-generation phosphatidylinositol 3 kinase (PI3K) δ inhibitor, has shown promising response rates in a phase 1/2 study in patients with previously treated B-cell malignancies. CITADEL-204 (NCT03144674) is a multicenter, open-label phase 2 study of parsaclisib in patients with relapsed or refractory (R/R) MZL. Here, we report preliminary results for patients who were not previously treated with a Bruton's tyrosine kinase inhibitor (BTKi-naïve). Methods: Eligible patients were ≥18 years of age with histologically confirmed MZL who received ≥1 prior line of systemic therapy, including anti-CD20 therapy, but were BTKi-naïve. Patients had documented disease progression or lack of response to the most recent regimen, had radiologically measurable lymphadenopathy or extranodal lymphoid malignancy (or histologically confirmed bone marrow infiltration in cases of splenic MZL), and an Eastern Cooperative Oncology Group performance status (ECOG PS) ≤2. Prophylaxis for Pneumocystis jirovecii pneumonia (PJP) was required. Patients were allocated to receive parsaclisib 20 mg once daily (QD) for 8 weeks followed by either 20 mg once weekly (weekly-dosing group [WG]) or 2.5 mg QD (daily-dosing group [DG]). Objective response rate (ORR) was the primary endpoint; complete response rate (CRR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety and tolerability were secondary endpoints. All radiology-based endpoints were assessed by an independent review committee (IRC). Safety was evaluated in all treated patients, and efficacy was evaluated in all treated patients who had a follow-up of ≥9 weeks, had at least 1 post-baseline assessment, or discontinued study participation prematurely. Results: From December 2017 to January 17, 2020 (data cut-off), 99 patients (WG, n = 28; DG, n = 71) were treated. Median age was 71 years; 52.5% of the patients were male, 94.9% had an ECOG PS ≤1, and 31.3%, 33.3%, and 35.4% had nodal, extranodal, and splenic MZL, respectively. The median number of prior systemic therapies was 2. At cut-off, 40 (40.4%) patients had discontinued treatment, including 20 (20.2%) for disease progression. The median parsaclisib exposure (range) was 7.5 months (0.4−22.4). At the data cut-off, 94 patients were evaluable for response, including 66 in DG (Table). Median (range) follow-up for the efficacy evaluable population was 11.1 months (1.2−25.0) overall and 9.5 months (1.2−25.0) in DG. The ORR (95% confidence interval [CI]) was 54.3% (43.7−64.6) overall and 57.6% (44.8−69.7) in DG; the ORR (95% CI) was 48.3% (29.4−67.5), 50.0% (31.9−68.1), and 63.6% (45.1−79.6) for patients with nodal, extranodal, and splenic MZL, respectively (Table). The median time to response was 8 weeks. The median DOR (95% CI) was 9.3 months (6.2−not evaluable [NE]) among all responders and 9.4 months (6.0-NE) in DG. The median PFS (95% CI) was 13.8 months (8.8−NE) overall and 11.5 months (8.3-NE) in DG. Among the 99 treated patients, the most common treatment-emergent AEs (TEAEs) were diarrhea (36.4% of patients), cough (18.2%), and rash (14.1%). The most common TEAEs grade ≥3 were neutropenia and diarrhea (8.1%, each). The most common serious TEAEs were febrile neutropenia and pneumonia (5.1%, each). TEAEs leading to dose interruption or dose reduction occurred in 47.5% and 14.1% of patients, respectively. TEAEs leading to discontinuation occurred in 15.2% of patients; the most common events were diarrhea (5.1%) and colitis (3.0%). TEAEs leading to death occurred in 4 patients, with 2 events, febrile neutropenia (n = 1) and sepsis (n = 1), deemed treatment related. New or worsening grade ≥3 laboratory test values of clinical interest included increase in alanine/aspartate amino transferase (2.0%/1.0% of patients), and decrease in neutrophil count (13.1%), platelet count (3.0%), and hemoglobin (3.0%). Conclusion: BTKi-naïve patients with R/R MZL achieved rapid and durable responses with single-agent parsaclisib. Comparable efficacy was observed in patients diagnosed with nodal, extranodal, or splenic MZL. Treatment with parsaclisib was generally well tolerated without unexpected toxicities. Updated data will be presented. Disclosures Phillips: Incyte: Consultancy, Other: travel expenses; Seattle Genetics: Consultancy; BMS: Consultancy; Bayer: Consultancy, Research Funding; Pharmacyclics: Consultancy; Abbvie: Consultancy, Research Funding; AstraZeneca: Consultancy; Beigene: Consultancy; Karyopharm: Consultancy; Cardinal Health: Consultancy. Corradini:KiowaKirin: Consultancy, Honoraria; Incyte: Consultancy; Daiichi Sankyo: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; F. Hoffman-La Roche Ltd: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Novartis: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Takeda: Consultancy, Honoraria, Other; BMS: Other; Kite: Consultancy, Honoraria; Servier: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Gilead: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Sanofi: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Other: Travel and accommodations paid by for. Gurion:Medison: Consultancy; Gilead Sciences: Consultancy; Takeda Pharmaceuticals: Consultancy; JC Health CARE: Honoraria; Roche: Honoraria. Avigdor:Takeda, Gilead, Pfizer: Consultancy, Honoraria; Janssen, BMS: Research Funding. Jurczak:MorphoSys: Research Funding; European Medicines Agency,: Consultancy; Sandoz-Novartis: Consultancy; Takeda: Research Funding; Roche: Research Funding; Pharmacyclics: Research Funding; Merck: Research Funding; MEI Pharma: Research Funding; Janssen China R&D: Consultancy, Research Funding; BeiGene: Consultancy, Research Funding; Bayer: Research Funding; Afimed: Research Funding; Celgene: Research Funding; Epizyme: Consultancy; Gilead Sciences: Research Funding; Nordic Nanovector: Research Funding; Servier: Research Funding; Maria Sklodowska-Curie National Research Institute of Oncology, Krakow, Poland: Current Employment; TG Therapeutics, Inc.: Research Funding; Acerta: Consultancy, Research Funding; Jagiellonian University, Krakow, Poland: Ended employment in the past 24 months; AstraZeneca: Consultancy. Mehta:Affimed: Research Funding; Kite/Gilead: Research Funding; Roche-Genentech: Research Funding; Gelgene/BMS: Research Funding; Oncotartis: Research Funding; Innate Pharmaceuticals: Research Funding; Seattle Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Takeda: Research Funding; fortyseven Inc/Gilead: Research Funding; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Merck: Research Funding; Juno Parmaceuticals/BMS: Research Funding. Zinzani:Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kirin Kyowa: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics, Inc.: Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Eusapharma: Consultancy, Speakers Bureau; Kyowa Kirin: Consultancy, Speakers Bureau; Immune Design: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Lossos:Seattle Genetics: Consultancy, Other; NCI: Research Funding; Stanford University: Patents & Royalties; Janssen Scientific: Consultancy, Other; Verastem: Consultancy, Honoraria; Janssen Biotech: Honoraria. Thieblemont:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel support; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding; Incyte: Honoraria; Bayer: Honoraria; Bristol-Myers Squibb: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Hospira: Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Cellectis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau. Zheng:Incyte: Current Employment, Current equity holder in publicly-traded company. Rappold:Incyte Corporation: Current Employment, Current equity holder in publicly-traded company. Zhao:Incyte Corporation: Current Employment, Current equity holder in publicly-traded company. Johnson:Incyte: Honoraria; Kite Pharma: Honoraria; Kymera: Honoraria; Boehringer Ingelheim: Consultancy; MorphoSys: Honoraria; Oncimmune: Consultancy; Takeda: Honoraria; Novartis: Honoraria; Epizyme: Consultancy, Research Funding; Janssen: Consultancy; Celgene: Honoraria; Bristol-Myers: Honoraria; Genmab: Honoraria; Epizyme: Consultancy, Research Funding; Janssen: Consultancy; Oncimmune: Consultancy.

Around half of patients with Hodgkin Lymphoma (HL) who progress or relapse through first line therapy can be cured with salvage chemotherapy followed by autologous stem cell transplant (ASCT). However, this leaves approximately 50% of patients that will relapse after ASCT. The pivotal phase II SG035-00303 trial demonstrated that these patients can be successfully treated with Brentuximab Vedotin (BV), and a proportion of them can be long term free of disease without any further intervention. The objective of the current study was to investigate whether these findings were borne out in the real world via interrogation of the EBMT registry. We retrospectively analysed data for 101 patients with HL who had BV as their first treatment for relapse after ASCT from 2012 to 2019. The median age at ASCT was 34 years (range: 19-65), 60% being male and with 62% being in complete response (CR) at the time of ASCT. Carmustine, Etoposide, Cytarabine and Melphalan (BEAM) was the most common conditioning regimen, having been employed in 72% of the cases. The median time from ASCT to relapse was 10.1 months (interquartile range (IQR): 6.1-25.1). The median time on BV was 3.4 months (IQR: 2.1-5.24). BV treatment resulted in a best overall response rate (ORR) of 59% with a CR rate of 37%. At last follow-up only 2 patients remain on treatment with BV. The main reason for discontinuation of BV was progression which occurred in 37% of the patients. In 32 cases (33%) the treatment was stopped electively to proceed to a second transplant, and overall nearly a quarter (22%) completed the full treatment course. Only 5% of patients stopped due to toxicity (peripheral neuropathy 2 and neutropenia, infusion reaction and other, 1 each). Further therapy was given after BV in over half of evaluable patients (58%), with check point inhibitors (CPIs) being the most common agents used (24% of these). Nearly two thirds (64/101) of the patients received a second transplant, which were nearly all allogeneic stem cell transplant (alloSCT, 59/64), and most of these (49/59) with reduced intensity conditioning (RIC). 26% of the alloSCT recipients experienced grade II-IV acute graft versus host disease (GvHD) and 25% developed chronic GvHD. At last follow up, 62% of all patients were alive with a median follow-up of 25 months after starting BV. Of these, 27 had received a second transplant, who were mostly in CR at last follow up (26/27) and a further 22 had relapsed. There were 11 patients of the 63 still alive who continued to be responding to BV without further therapy with a median duration of response of 30 months. In conclusion BV use for relapse after ASCT was well tolerated generally, with only a minority of patients stopping treatment due to toxicity. However, although almost two thirds of the patients achieved a response, further treatment was often needed after BV, notably with CPIs and most patients were consolidated with a RIC alloSCT. These results confirm that only a minority of patients can achieve a durable remission with BV alone. Disclosures Brice: Takeda France: Consultancy, Honoraria; Millennium Takeda: Research Funding; BMS: Honoraria. Blaise:Molmed: Consultancy, Honoraria; Jazz Pharmaceuticals: Honoraria; Sanofi: Honoraria; Pierre Fabre medicaments: Honoraria. Stamatoullas:Celgene: Honoraria; Takeda: Consultancy. Robak:Takeda: Consultancy, Research Funding; UCB: Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Other: Travel grant, Research Funding; Amgen: Consultancy, Other: Travel grant; Roche: Consultancy, Other: Travel grant, Research Funding; Abbvie: Consultancy, Honoraria, Other: Travel grant, Research Funding; Gilead: Consultancy, Research Funding; BeiGene: Consultancy, Research Funding; Acerta: Research Funding; Morphosys AG: Research Funding. Wahlin:Roche and Gilead: Consultancy.

In lymphomas of B-cell origin, cancer cells orchestrate an inflammatory microenvironment of immune and stromal cells that sustain the tumor cell survival and growth, known as a tumor microenvironment (TME). The features of the TME differ between the different lymphoma types, ranging from extremely inflammatory, such as in Hodgkin lymphoma, to anergic, leading to immune deficiency and susceptibility to infections, such as in chronic lymphocytic leukemia. Understanding the characteristic features of the TME as well as the interactions between cancer and TME cells has given insight into the pathogenesis of most lymphomas and contributed to identify novel therapeutic targets. Here, we summarize the preclinical data that contributed to clarifying the role of the immune cells in the TME of different types of lymphomas of B-cell origin, and explain how the understanding of the biological background has led to new clinical applications. Moreover, we provide an overview of the clinical results of trials that assessed the safety and efficacy of drugs directly targeting TME immune cells in lymphoma patients.

The clinical course of follicular lymphoma (FL) is highly variable. Recently the m7-FL international prognostic index (FLIPI) integrating performance status, FLIPI score and the mutational status of seven genes, was shown to stratify patients into "low-risk" and "high-risk" with respect to 5-year failure-free survival after first-line immunochemotherapy. Our aim was to evaluate the model after rituximab without chemotherapy. The Nordic Lymphoma Group performed two randomized clinical trials on indolent lymphoma patients receiving single rituximab and rituximab with interferon-α2a. In total, 95 FL patients had sufficient fresh-frozen diagnostic material for sequencing. A targeted panel for the genes EZH2, ARID1A, MEF2B, EP300, FOXO1, CREBBP and CARD11 was utilized for m7-FLIPI score calculation. With a median follow-up of 10·6 years, 76% of patients were alive. No difference in time to treatment failure (TTF), defined as the interval between start of trial therapy and initiation of new therapy or death, nor overall survival (OS) was found between the m7-FLIPI risk groups (log-rank P = 0·94 and 0·99, respectively). EZH2 mutations were associated with longer TTF (log-rank P = 0·04) and in EP300 mutations were associated with shorter TTF (log-rank P = 0·01). We conclude that the prognostic value of the m7-FLIPI clinicogenetic model seems dependent on therapeutic regimen.

TPS7568 Background: Most patients with the indolent non-Hodgkin lymphoma (NHL) subtypes FL or MZL respond to first-line treatment but relapse is common, and there is no single standard treatment for patients with R/R FL or MZL. Tafasitamab is an Fc-engineered humanized monoclonal antibody (mAb) against CD19 which is broadly expressed in FL and MZL, and regulates B-cell proliferation via B-cell receptor signaling. In preclinical studies, tafasitamab has shown activity against NHL cell lines in combination with rituximab (anti-CD20 mAb) and lenalidomide (LEN). Tafasitamab monotherapy has shown promising clinical activity in a phase 2a study in patients with R/R NHL (NCT01685008), with an ORR of 29% (n/N = 10/34) in patients with FL and 33% (n/N = 3/9) in patients with MZL. In an ongoing phase 2, single-arm study (L-MIND, NCT02399085), tafasitamab plus LEN followed by tafasitamab alone demonstrated an ORR of 57.5% (n/N = 46/80) in patients with R/R diffuse large B-cell lymphoma (FDA approved indication). These preclinical and clinical observations from phase 2 trials suggest a potential clinical benefit of tafasitamab plus LEN and rituximab for patients with R/R FL or MZL. Methods: This phase 3 double-blind, placebo-controlled, randomized study is designed to investigate whether tafasitamab plus LEN and rituximab provides improved clinical benefit compared with LEN and rituximab in patients with R/R FL or R/R MZL. Patients will be randomized 1:1 to receive tafasitamab (12 mg/kg IV on days 1, 8, 15, and 22 of a 28-day cycle [cycles 1–3], then days 1 and 15 [cycles 4–12]) plus LEN (20 mg PO QD, days 1–21/ cycle for 12 cycles) and rituximab (375 mg/m2 IV on days 1, 8, 15, and 22 of cycle 1, then day 1 of cycles 2–5), or placebo (0.9% saline solution IV) plus LEN and rituximab. The primary study endpoint is PFS (investigator assessed [INV] by Lugano 2014 criteria) for patients with FL. Key secondary endpoints are PFS (INV) in overall population (FL and MZL), PET-CR rate (INV) at end of treatment (4–8 weeks after last treatment) and OS in patients with FL. Inclusion criteria include age ≥18 y, histologically confirmed FL (grade 1, 2, or 3a) or MZL (nodal, splenic, or extranodal), documented R/R disease, ≥1 prior systemic anti-CD20 therapy (including anti-CD20 refractory disease), ECOG PS ≤2, adequate systemic organ function, and high tumor burden (per GELF criteria). Exclusion criteria include prior rituximab plus LEN treatment, history of radiotherapy for other diseases (≥25% of bone marrow), nonhematologic malignancy, congestive heart failure (LVEF < 50%), active systemic infection, known CNS lymphoma, or severe immunocompromised state. inMIND (NCT04680052, EudraCT2020-004407-13) is currently enrolling patients; planned enrollment is 528 patients with R/R FL and 60–90 patients with R/R MZL. Clinical trial information: NCT04680052.

8007 Background: Bruton tyrosine kinase (BTK) inhibition is an emerging standard of care for WM. ASPEN is a randomized phase 3 study comparing zanubrutinib (ZANU), a potent and selective BTK inhibitor, versus ibrutinib (IBR), a first generation BTK inhibitor, in WM patients. Methods: Patients with WM and MYD88 mutation were randomly assigned 1:1 to receive ZANU (160 mg twice daily) or IBR (420 mg once daily). Patients without MYD88 mutations were assigned to a separate cohort, received ZANU, and are reported separately. Randomization was stratified by CXCR4 mutational status and the number of lines of prior therapy (0 vs 1-3 vs >3). The primary end point was the proportion of patients achieving a complete response or very good partial response (CR+VGPR). Sample size was calculated to provide 81% power to detect a difference in CR+VGPR rate of 35% vs 15% in the subset of patients with relapsed or refractory (R/R) WM. Primary analysis was planned to occur at ~12 months after last patient enrolled. Results: In total, 201 patients were randomized from Jan 2017 to Jul 2018. The treatment groups were well balanced for important baseline factors, except in the ZANU arm there were more elderly patients (aged >75 years, 33.3% vs 22.2%) and more anemia (hemoglobin ≤110 g/L, 65.7% vs 53.5%). At a median follow-up of 19.4 months, the rate of CR+VGPR was 28.4% vs 19.2% with ZANU vs IBR, respectively (2-sided P=0.09). Rates of atrial fibrillation, contusion, diarrhea, edema peripheral, hemorrhage, muscle spasms, pneumonia, and adverse events (AEs) leading to discontinuation or death were lower with ZANU. The rate of neutropenia was higher with ZANU (Table); however, grade ≥ 3 infection rates were similar (17.8% vs 19.4%). Conclusions: ASPEN is the largest phase 3 trial of BTK inhibitors in WM and the first head-to-head comparison of BTK inhibitors in any disease. Although not statistically significant, ZANU was associated with a higher CR+VGPR response rate, and demonstrated clinically meaningful advantages in safety and tolerability compared to IBR. Clinical trial information: NCT03053440 . [Table: see text]