Radiotherapy dose response in bulky relapsed/refractory large B-cell lymphoma.

PURPOSE: To assess whether a radiotherapy (RT) dose affects response in bulky tumors in relapsed/refractory (r/r) diffuse large B-cell lymphoma (DLBCL). METHODS: Data from r/r DLBCL patients treated with salvage- or palliative-intent RT (2008-2020) at a single institution were examined. Index lesion size ≥7.5 cm was defined as bulky. Equivalent doses in 2 Gray (Gy) fractions (EQD2) were calculated to compare doses between conventional and hypofractionated (HF, ≥2.5 Gy/fraction) schemes. Objective response rates (ORR) were compared using non-parametric Mann-Whitney U test or Kruskal-Wallis tests with Dunn's multiple comparison corrections. Freedom from local progression (FFLP) was assessed using Kaplan-Meier and Cox proportional hazard regression analyzes. RESULTS: 183 courses of 151 unique patients were included (salvage: 37%, palliative: 63%). Non-bulky and bulky tumors were irradiated in 109 (60%) and 74 (40%) courses, respectively. Median EQD2 was 33 Gy (IQR=23-39 Gy) with HF in 84 (46%) cases. Of those with post-RT imaging (80%), the ORR was 59% with a trend towards worsened ORR in bulky tumors (50% vs. 65%, p=0.077). For bulky tumors, RT regimens with EQD2s >30 Gy were associated with better ORR (≤30 Gy vs. >30 Gy: 27% vs. 64%, p=0.0073), whereas a lower EQD2 cut-off was sufficient for non-bulky tumors (≤20 Gy vs. >20 Gy: 38% vs. 75%, p=0.0011). On multivariable regression, bulky tumor size was associated with worsened FFLP (HR=2.07, 95% CI=1.16-3.68, p=0.014), while high EQD2s >30 Gy were associated with better FFLP (HR=0.48, 95% CI=0.25-0.93, p=0.031). Bulky tumors treated with EQD2s ≤30 Gy had the lowest median FFLP (4.0 months), while EQD2s >30 Gy had an unreached median FFLP (p=0.0047). CONCLUSIONS: Bulky r/r DLBCL tumors were associated with less favorable tumor control outcomes in the salvage and palliative settings. RT regimens with higher EQD2s (>30 Gy) should be considered if durable local control of bulky tumors is desired.

The CNS relapse in T-cell lymphoma index predicts CNS relapse in patients with T- and NK-cell lymphomas.

ABSTRACT: Little is known about risk factors for central nervous system (CNS) relapse in mature T-cell and natural killer cell neoplasms (MTNKNs). We aimed to describe the clinical epidemiology of CNS relapse in patients with MTNKN and developed the CNS relapse In T-cell lymphoma Index (CITI) to predict patients at the highest risk of CNS relapse. We reviewed data from 135 patients with MTNKN and CNS relapse from 19 North American institutions. After exclusion of leukemic and most cutaneous forms of MTNKNs, patients were pooled with non-CNS relapse control patients from a single institution to create a CNS relapse-enriched training set. Using a complete case analysis (n = 182), including 91 with CNS relapse, we applied a least absolute shrinkage and selection operator Cox regression model to select weighted clinicopathologic variables for the CITI score, which we validated in an external cohort from the Swedish Lymphoma Registry (n = 566). CNS relapse was most frequently observed in patients with peripheral T-cell lymphoma, not otherwise specified (25%). Median time to CNS relapse and median overall survival after CNS relapse were 8.0 and 4.7 months, respectively. We calculated unique CITI risk scores for individual training set patients and stratified them into risk terciles. Validation set patients with low-risk (n = 158) and high-risk (n = 188) CITI scores had a 10-year cumulative risk of CNS relapse of 2.2% and 13.4%, respectively (hazard ratio, 5.24; 95% confidence interval, 1.50-18.26; P = .018). We developed an open-access web-based CITI calculator (https://redcap.link/citicalc) to provide an easy tool for clinical practice. The CITI score is a validated model to predict patients with MTNKN at the highest risk of developing CNS relapse.

CAR T-Cell Immunotherapy in Minority Patients with Lymphoma.

BACKGROUND: Administration of anti-CD19 chimeric antigen receptor T-cell (CART19) immunotherapy for large B-cell lymphomas (LBCLs), a subset of non-Hodgkin lymphoma (NHL), involves high costs and access to specialized tertiary care centers. We investigated whether minority health populations (MHPs) have equal access to CART19 and whether their outcomes are similar to those of non-MHPs. METHODS: We analyzed the prevalence and clinical outcomes of patients treated with commercial CART19 at two geographically and socioeconomically different institutions: the Abramson Cancer Center (ACC, Philadelphia, Pennsylvania) and the Knight Cancer Institute (KCI, Portland, Oregon). RESULTS: In the ACC catchment area, 8956 patients were diagnosed with NHL between 2015 and 2019 (latest available data from the state registry), including 17.9% MHPs. In the ACC, between 2018 and 2022 (CART became available in 2018), 1492 patients with LBCL were treated, and 194 received CART19. The proportion of MHPs was 15.7% for the entire LBCL cohort but only 6.7% for the CART19 cohort. During the same time, in the KCI catchment area, 4568 patients were diagnosed with NHL, including 4.2% MHPs. In the KCI, 396 patients with LBCL were treated, and 47 received CART19. The proportion of MHPs was 6.6% for the entire LBCL cohort and 4.2% for the CART19 cohort. The 3-month response, survival, and toxicities after CART19 infusion showed similar results, although the number of patients who were treated was limited. CONCLUSIONS: This study shows that the access of MHPs to tertiary centers for LBCL care was preserved but appeared reduced for commercial CART19 immunotherapy. Although clinical outcomes of MHPs seemed similar to those of non-MHPs, the small sample size precludes drawing firm conclusions. Further studies are needed. (Funded by the Laffey McHugh Foundation and others.).

Efficacy and safety of bendamustine for lymphodepletion before lisocabtagene maraleucel.

Bendamustine has been retrospectively shown to be an effective and safe lymphodepletion regimen prior to the anti-CD19 chimeric antigen receptor T cell (CART) products tisagenlecleucel and axicabtagene ciloleucel, as well as the anti-BCMA CART products idecabtagene vicleucel and ciltacabtagene autoleucel. However, bendamustine as lymphodepletion prior to lisocabtagene maraleucel (liso-cel), a 4-1BB co-stimulated, fixed CD4:CD8 ratio anti-CD19 CART product, has not been described yet. Thus, we studied a cohort of sequentially-treated patients with large B-cell lymphomas who received bendamustine lymphodepletion before liso-cel at the University of Pennsylvania between 5/2021 and 12/2023 (n = 31). Patients were evaluated for toxicities and responses. Of note, 7 patients (22.6%) would have dnot met the inclusion criteria for the registrational liso-cel clinical trials, mostly due to older age. Overall and complete response rates were 76.9% and 73.1%, respectively. At a median follow-up of 6.3 months, the 6-month progression-free and overall survival were 59.9% and 91.1%, respectively. Rates of cytokine-release syndrome (CRS) and neurotoxicity (ICANS) of any grade were 9.7% and 9.7%, respectively, with no grade ≥ 3 events. No infections were reported during the first 30 days following liso-cel infusion. Neutropenia ≥ grade 3 was observed in 29.0% of patients; thrombocytopenia ≥ grade 3 occurred in 9.7%. In conclusion, bendamustine lymphodepletion before liso-cel appears to be a strategy that can drive tumor responses while ensuring a mild toxicity profile.

Bendamustine as Lymphodepletion for Brexucabtagene Autoleucel Therapy of Mantle Cell Lymphoma.

Brexucabtagene autoleucel (brexu-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for treatment of relapsed/refractory mantle cell lymphoma (MCL). During a fludarabine shortage, we used bendamustine as an alternative to standard cyclophosphamide/fludarabine (cy/flu) lymphodepletion (LD) prior to brexu-cel. We assessed MCL patient outcomes as well as CAR T-cell expansion and persistence after brexu-cel following bendamustine or cy/flu LD at our center. This was a retrospective single institution study that utilized prospectively banked blood and tissue samples. Clinical efficacy was assessed by 2014 Lugano guidelines. CAR T-cell expansion and persistence in peripheral blood were assessed on day 7 and at ≥month 6 for patients with available samples. Seventeen patients received bendamustine and 5 received cy/flu. For the bendamustine cohort, 14 (82%) received bridging therapy and 4 (24%) had CNS involvement. Fifteen patients (88%) developed CRS with 4 (24%) ≥grade 3 events. Six (35%) patients developed ICANS with 4 (24%) events ≥grade 3. No patient had ≥grade 3 cytopenias at day 90. Best objective (BOR) and complete response (CRR) rates were 82% and 65%, respectively. At 24.5 months median follow-up, 12-month progression-free survival (PFS) was 45%, 24-month PFS was 25%, and median duration of response was 19 months. Median OS was not reached. BOR was 25% (1/4) for patients with CNS involvement. CAR transgene expansion after bendamustine LD was observed on day 7 in all (4/4) patients tested and persisted at ≥6 months (2/2), regardless of response. Bendamustine LD before brexu-cel for MCL is feasible and safe with a lower frequency and shorter duration of cytopenias than reported for cy/flu. Both CAR T-cell expansion and persistence were observed after bendamustine LD. Outcomes appear comparable to the real world outcomes reported with cy/flu LD.

Immunologic predictors of vaccine responsiveness in patients with lymphoma and CLL.

Patients with B-cell lymphomas have altered cellular components of vaccine responses due to malignancy and therapy, and the optimal timing of vaccination relative to therapy remains unknown. SARS-CoV-2 vaccines created an opportunity for new insights in vaccine timing because patients were challenged with a novel antigen across multiple phases of treatment. We studied serologic mRNA vaccine response in retrospective and prospective cohorts with lymphoma and CLL, paired with clinical and research immune parameters. Reduced serologic response was observed more frequently during active therapies, but non-response was also common within observation and post-treatment groups. Total IgA and IgM correlated with successful vaccine response. In individuals treated with CART-19, non-response was associated with reduced B and T follicular helper cells. Predictors of vaccine response varied by disease and therapeutic group, and therefore further studies of immune health during and after cancer therapies are needed to allow individualized vaccine timing.

T cell lymphoma and secondary primary malignancy risk after commercial CAR T cell therapy.

We report a T cell lymphoma (TCL) occurring 3 months after anti-CD19 chimeric antigen receptor (CAR) T cell immunotherapy for non-Hodgkin B cell lymphoma. The TCL was diagnosed from a thoracic lymph node upon surgery for lung cancer. The TCL exhibited CD8+ cytotoxic phenotype and a JAK3 variant, while the CAR transgene was very low. The T cell clone was identified at low levels in the blood before CAR T infusion and in lung cancer. To assess the overall risk of secondary primary malignancy after commercial CAR T (CD19, BCMA), we analyzed 449 patients treated at the University of Pennsylvania. At a median follow-up of 10.3 months, 16 patients (3.6%) had a secondary primary malignancy. The median onset time was 26.4 and 9.7 months for solid and hematological malignancies, respectively. The projected 5-year cumulative incidence is 15.2% for solid and 2.3% for hematological malignancies. Overall, one case of TCL was observed, suggesting a low risk of TCL after CAR T.

TP53 mutations predict for poor outcomes in patients with newly diagnosed aggressive B-cell lymphomas in the current era.

Genetic subgroups of diffuse large B-cell lymphoma (DLBCL) have been identified through comprehensive genomic analysis; however, it is unclear whether this can be applied in clinical practice. We assessed whether mutations detected by clinical laboratory mutation analysis (CLMA) were predictive of outcomes in patients with newly diagnosed DLBCL/high-grade B-cell lymphoma (HGBL). Patients diagnosed from 2018 to 2022 whose biopsy samples were subjected to CLMA and who received rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone or rituximab plus etoposide, prednisolone, vincristine, cyclophosphamide, and doxorubicin were analyzed for overall/complete response rate (ORR/CRR) and estimated progression-free/overall survival (PFS/OS). CLMA was successfully performed in 117 of 122 patient samples (96%), with a median turnaround time of 17 days. Median duration of follow-up was 31.3 months. Of the mutations detected in ≥10% of the samples, only TP53 was associated with both progression and death at 2 years. TP53 mutations were detected in 36% of tumors, and patients with TP53 mutations experienced significantly lower ORR (71% vs 90%; P = .009), CRR (55% vs 77%; P = .01), 2-year PFS (57% vs 77%; P = .006), 2-year OS (70% vs 91%; P = .001), and median OS after relapse (6.1 months vs not yet reached; P = .001) as than those without TP53 mutations. Furthermore, patients with TP53 loss-of-function (LOF) mutations experienced lower rates of 2-year PFS/OS than those with non-LOF mutations and inferior or near-inferior 2-year PFS if harboring high-risk clinicopathologic features. TP53 mutations identified through CLMA can predict for inferior outcomes in patients with newly diagnosed DLBCL/HGBL. Results of CLMA can be used in real time to inform prognosis and/or identify candidates for clinical trials.

Brentuximab vedotin plus AVD for Hodgkin lymphoma: incidence and management of peripheral neuropathy in a multisite cohort.

Brentuximab vedotin (BV) in combination with doxorubicin, vinblastine, and dacarbazine (AVD) is increasingly used for frontline treatment of stage III/IV classical Hodgkin lymphoma (cHL). Peripheral neuropathy (PN) was the most common and treatment-limiting side effect seen in clinical trials but has not been studied in a nontrial setting, in which clinicians may have different strategies for managing it. We conducted a multisite retrospective study to characterize PN in patients who received BV + AVD for newly diagnosed cHL. One hundred fifty-three patients from 10 US institutions were eligible. Thirty-four patients (22%) had at least 1 ineligibility criteria for ECHELON-1, including stage, performance status, and comorbidities. PN was reported by 80% of patients during treatment; 39% experienced grade (G) 1, 31% G2, and 10% G3. In total, BV was modified in 44% of patients because of PN leading to BV discontinuation in 23%, dose reduction in 17%, and temporary hold in 4%. With a median follow-up of 24 months, PN resolution was documented in 36% and improvement in 33% at the last follow-up. Two-year progression-free survival (PFS) for the advanced-stage patients was 82.7% (95% confidence interval [CI], 0.76-0.90) and overall survival was 97.4% (95% CI, 0.94-1.00). Patients who discontinued BV because of PN did not have inferior PFS. In the nontrial setting, BV + AVD was associated with a high incidence of PN. In our cohort, which includes patients who would not have been eligible for the pivotal ECHELON-1 trial, BV discontinuation rates were higher than previously reported, but 2-year outcomes remain comparable.

Survival Outcomes for Patients with Relapsed/ Refractory Aggressive B Cell Lymphomas Following Receipt of High-Dose Chemotherapy/Autologous Stem Transplantation and/or Chimeric Antigen Receptor-Modified T Cells.

Patients diagnosed with relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL) or high-grade B cell lymphoma (HGBL) may achieve prolonged survival following receipt of high-dose chemotherapy/autologous stem cell transplantation (HDC/ASCT) or CD19-directed chimeric antigen receptor modified T cell therapy (CART19). Although early results from randomized clinical trials suggest that assignment to CART19 versus salvage immunochemotherapy as second-line therapy results in improved survival, analysis of a large series of patients who actually received HDC/ASCT or CART19 has yet to be performed. Such an analysis may inform future research efforts to optimize the risk stratification of R/R DLBCL/HGBL patients who are candidates for either therapy. The aim of this study was to evaluate clinicopathologic factors predictive of freedom from treatment failure (FFTF) for R/R DLBCL/HGBL patients following receipt of HDC/ASCT or CART19, and to compare patterns of treatment failure (TF) in R/R DLBCL/HGBL patients receiving HDC/ASCT and those receiving CART19. THE STUDY GROUP COMPRISED: patients age ≤75 years with R/R DLBCL/HGBL who received HDC/ASCT demonstrating partial or complete metabolic response to salvage immunochemotherapy and/or CART19 in the standard of care setting at the University of Pennsylvania between 2013 and 2021. Survival analyses were performed from the time of infusion of either HDC/ASCT or CART19, as well as at landmark time points postinfusion for patients who achieved FFTF. For 100 HDC/ASCT patients with a median follow-up of 62.7 months, the estimated 36-month FFTF and overall survival (OS) rates were 59% and 81%, respectively. For 109 CART19 patients with a median follow-up of 37.6 months, the estimated 36-month FFTF and OS rates were 24% and 48%, respectively. HDC/ASCT patients had significantly higher rates of estimated 36-month FFTF when they achieved actual FFTF at 3, 6, 12 and 24 months. Additionally, the rates of baseline characteristics predictive of TF at 36 months for either HDC/ASCT or CART19 patients were either similar to or significantly lower for CART19 patients compared to HDC/ASCT patients who achieved actual FFTF at 3, 6, 12, and 24 months. Patients with R/R DLBCL/HGBL achieving response to salvage immunochemotherapy who received HDC/ASCT had a high rate of estimated FFTF regardless of whether they harbored features predictive of resistance to salvage immunochemotherapy, which may be more durable than that of R/R DLBCL/HGBL patients receiving CART19. These findings support further investigation of disease characteristics, such as molecular features, that may predict response to salvage immunochemotherapy in patients fit for HDC/ASCT.

Modulation of the gut microbiota engages antigen cross-presentation to enhance antitumor effects of CAR T cell immunotherapy.

Several studies have shown the influence of commensal microbes on T cell function, specifically in the setting of checkpoint immunotherapy for cancer. In this study, we investigated how vancomycin-induced gut microbiota dysbiosis affects chimeric antigen receptor (CAR) T immunotherapy using multiple preclinical models as well as clinical correlates. In two murine tumor models, hematopoietic CD19+-A20 lymphoma and CD19+-B16 melanoma, mice receiving vancomycin in combination with CD19-directed CAR T cell (CART-19) therapy displayed increased tumor control and tumor-associated antigens (TAAs) cross-presentation compared with CART-19 alone. Fecal microbiota transplant from human healthy donors to pre-conditioned mice recapitulated the results obtained in naive gut microbiota mice. Last, B cell acute lymphoblastic leukemia patients treated with CART-19 and exposed to oral vancomycin showed higher CART-19 peak expansion compared with unexposed patients. These results substantiate the role of the gut microbiota on CAR T cell therapy and suggest that modulation of the gut microbiota using vancomycin may improve outcomes after CAR T cell therapy across tumor types.

Salvage radiotherapy for relapsed/refractory non-Hodgkin lymphoma following CD19 chimeric antigen receptor T-cell (CART) therapy.

Background and purpose: CD19-targeting chimeric antigen receptor T-cell (CART) therapy is a promising treatment for relapsed/refractory non-Hodgkin lymphoma, but most patients experience post-CART progression. We describe our institutional experience of salvage radiotherapy (SRT) in this setting. Materials and methods: Of 94 patients who received CART therapy from 2018 to 2020, 21 received SRT for post-CART progression. Patients were divided into two groups: locoregional disease (n = 9 [43 %], all disease encompassable within an RT field) and advanced disease (n = 12 [57 %]). Patterns of failure, progression-free survival (PFS), overall survival (OS), and toxicity were assessed. Results: Median time from CART infusion to SRT was 4.0 months (range, 0.6-11.5 months). In the locoregional disease group, 8/9 patients (89 %) were treated with comprehensive SRT to a median dose of 37.5 Gy in a median of 15 fractions. In the advanced disease group, all patients (n = 12) were treated with focal SRT to a median dose of 20.8 Gy in a median of 5 fractions. Median follow-up post-SRT was 15.2 months. In-field response was observed in 8/9 (89 %) in the locoregional disease and 8/9 (89 %) evaluable patients in the advanced disease groups. 17/18 evaluable patients (94 %) patients experienced post-SRT progression, all with a distant component. Median OS was 7.4 months; 21 months for locoregional disease versus 2.4 months for advanced disease (p = 0.0002). Median PFS was 1.1 month, and similarly poor regardless of group. No grade ≥ 3 toxicities occurred. Conclusions: SRT post-CART therapy appears safe with encouraging in-field response but high rates of out-of-field progression, even for those presenting with locoregional disease, highlighting the need for integration of novel systemic agents.

Radiation Therapy for Relapsed or Refractory Diffuse Large B-Cell Lymphoma: What Is the Right Regimen for Palliation?

Purpose: To report objective response rates (ORR), time to local failure (TTLF), and overall survival (OS) among patients with relapsed or refractory diffuse large B-cell lymphoma after salvage- or palliative-intent radiation therapy (RT) and to investigate whether outcomes differed with conventional versus hypofractionated (≥2.5 Gy/fraction) RT. Methods and Materials: A single-institution observational cohort study was performed for patients who completed a course of RT for relapsed or refractory diffuse large B-cell lymphoma between January 1, 2008, and April 1, 2020. Predictors of ORR, TTLF, and OS were calculated using univariable and multivariable regression models. The Kaplan-Meier method was used to estimate TTLF and OS, and log-rank analysis was used to compare outcomes. Equivalent dose in 2 Gy fractions (EQD2) was calculated using an α/ß of 10. Results: One-hundred and sixty-nine patients were treated with 205 RT courses (73 [36%] salvage, 132 [64%] palliative), and hypofractionated RT was used in 100 RT courses (49%). Median RT dose was 30 Gy (range, 8-60 Gy). ORR was 60% for the total cohort (53% and 69% for palliative and salvage cohorts, respectively). Over a median follow-up time of 4 months, median OS in all patients was 5 months (3 and 22 months for palliative and salvage cohorts, respectively). No statistically significant differences in ORR, TTLF, and OS were observed with hypofractionation compared with conventional fractionation. EQD2 ≥35 Gy was associated with improved ORR (odds ratio, 3.79 [1.19-12.03]; P = .024) and prolonged TTLF (0.39 [0.18-0.87]; P = .022), while double-hit receptor status (8.18 [1.08-62.05]; P = .042), cell of origin (3.87 [1.17-8.74]; P = .0012), and bulky disease (≥7.5 cm; 2.12 [1.18-3.81]; P = .012) were associated with inferior TTLF. In the palliative-only cohort, a low-dose regimen of 8 Gy in 2 fractions was associated with similar ORR compared with other fractionation schema but trended towards inferior TTLF (P = .36). Conclusions: Hypofractionation is not associated with differences in disease outcomes for patients with relapsed or refractory diffuse large B-cell lymphoma, while higher RT dose (EQD2 ≥35 Gy) may improve ORR and TTLF. Future work is warranted to elucidate the ideal dose and fractionation schema for such patients who will likely also undergo novel systemic agents and cellular therapies.

Mutation analysis performed on tumor biopsies from patients with newly-diagnosed germinal center aggressive B cell lymphomas.

Comprehensive genomic analyses of tumor biopsies from patients with newly-diagnosed germinal center B cell (GCB) diffuse large B cell/high grade B cell lymphoma (DLBCL/HGBL) have identified molecular subtypes predictive of inferior survival, which are characterized by somatic mutations that can be detected through clinical laboratory mutation analysis (CLMA). To determine the frequency and predictive value of individual genetic mutations associated with these experimentally-defined poor-risk subgroups, we reviewed the findings from CLMA performed on tumors from patients with newly-diagnosed GCB DLBCL/HGBL who were previously treated at our institution. CLMA was successfully performed on 58/59 patient tumor biopsies with a median turnaround time of 16 days, and 51 on which CLMA was routinely performed with adequate clinical follow-up were analyzed. Patients whose tumors demonstrated CREBBP mutation experienced a lower estimated rate of 2-year disease free survival (DFS) as compared to those whose tumors did not (45% [95% CI 18-68%] vs. 67% [95% CI 44-83%], P = 0.045). CREBBP mutations may be frequent and predict for inferior DFS in patients with newly-diagnosed GCB DLBCL/HGBL. Furthermore, CLMA may be practically-applied to translate experimental findings into those with more direct application to risk stratification and clinical trial design in subsets of patients with DLBCL/HGBL.

Modulation of BCL-2 in Both T Cells and Tumor Cells to Enhance Chimeric Antigen Receptor T-cell Immunotherapy against Cancer.

Chimeric antigen receptor T-cell (CART) immunotherapy led to unprecedented responses in patients with refractory/relapsed B-cell non-Hodgkin lymphoma (NHL); nevertheless, two thirds of patients experience treatment failure. Resistance to apoptosis is a key feature of cancer cells, and it is associated with treatment failure. In 87 patients with NHL treated with anti-CD19 CART, we found that chromosomal alteration of B-cell lymphoma 2 (BCL-2), a critical antiapoptotic regulator, in lymphoma cells was associated with reduced survival. Therefore, we combined CART19 with the FDA-approved BCL-2 inhibitor venetoclax and demonstrated in vivo synergy in venetoclax-sensitive NHL. However, higher venetoclax doses needed for venetoclax-resistant lymphomas resulted in CART toxicity. To overcome this limitation, we developed venetoclax-resistant CART by overexpressing mutated BCL-2(F104L), which is not recognized by venetoclax. Notably, BCL-2(F104L)-CART19 synergized with venetoclax in multiple lymphoma xenograft models. Furthermore, we uncovered that BCL-2 overexpression in T cells intrinsically enhanced CART antitumor activity in preclinical models and in patients by prolonging CART persistence. SIGNIFICANCE: This study highlights the role of BCL-2 in resistance to CART immunotherapy for cancer and introduces a novel concept for combination therapies-the engineering of CART cells to make them resistant to proapoptotic small molecules, thereby enhancing the therapeutic index of these combination therapies. This article is highlighted in the In This Issue feature, p. 2221.

Outcomes of Tisagenlecleucel in Lymphoma Patients With Predominant Management in an Ambulatory Setting.

INTRODUCTION: Chimeric antigen receptor T-cell therapy (CAR T) is a revolutionary adoptive immunotherapy approach in lymphoma; however, substantial resources are necessary for administration and care of these patients. Our institution has administered tisagenlecleucel primarily in an outpatient setting, and here we report our clinical outcomes. PATIENTS AND METHODS: We conducted a single institution, retrospective study investigating outcomes of adult lymphoma patients treated with commercial tisagenlecleucel between 10/2017 and 12/2020. We analyzed patient characteristics and outcomes of efficacy and safety including overall response rate, progression-free survival, overall survival and cytokine-release syndrome, neurotoxicity, and hospitalizations. RESULTS: Seventy-two patients with relapsed or refractory non-Hodgkin lymphoma (NHL) who received commercial tisagenlecleucel were identified; 68 (94.4%) patients received outpatient tisagenlecleucel. The overall response rate was 43% with a complete response observed in 25 patients (34.7%). At a median follow-up of 9.1 months, the median progression-free survival was 3.3 months. Grade 3-4 cytokine release syndrome was not observed in the study group and two patients had grade 3-4 neurotoxicity. Twenty-six patients (36.1%) were admitted within 30 days after infusion with a median length of stay of 5 days. Fourteen patients (19.4%) were admitted within 72 hours of infusion. No patient died of CAR T cell-related toxicity. CONCLUSION: Our experience affirms treatment with tisagenlecleucel in the outpatient setting is safe and feasible with close supervision and adequate institutional experience. After infusion, adverse events were manageable and the majority of patients did not require hospitalization.