McGuirk, Joseph P.

Introduction: Lymphodepletion (LD) chemotherapy is critical for the efficacy of CAR-T therapy by eradicating immunosuppressive cells, inducing costimulatory molecules, and promoting expansion and persistence of CAR-T cells. It also can contribute to an increased risk of infections, cytopenia, and other toxicities. We evaluated the utilization of varying LD regimens used in standard-of-care (SOC) autologous B-cell maturation antigen-directed (BCMA) CAR-T therapy with ide-cel or cilta-cel for relapsed/refractory multiple myeloma (RRMM) and the effect on outcomes and toxicity. Methods: Data were retrospectively collected from patients with RRMM who underwent LD and CAR-T cell infusion by December 31, 2022, from 13 US academic institutions with SOC ide-cel or cilta-cel. Response rates and other categorical variables, specifically LD regimen, were tested for association using Wilcoxon rank-sum (or Kruskal-Wallis for three or more groups) or Fisher's exact tests, respectively. Results: A total of 523 patients were infused at the time of data cut-off with 489 patients evaluable for safety and survival analyses; 368 (75%) were infused with ide-cel and 121 (25%) with cilta-cel. The median age was 65 years old (range 30-90) with 206 females (42%) and 283 males (58%), and 13% with ECOG performance status ≥ 2 at time of LD. Fludarabine and cyclophosphamide (Flu/Cy) LD was used in 422 patients while 67 patients received other LD regimens including bendamustine-based (n = 35, 52%), cladribine-based (n = 25, 37%) or cyclophosphamide alone (n = 7, 10%). The primary reason for use of Flu/Cy LD was institutional guidance or SOC in 378 patients (90%), while the primary reason for use of other LD regimens was due to the fludarabine shortage in 65 patients (97%) with 3% citing physician's choice or institutional guidance. No significant difference was identified among response outcomes, with those receiving Flu/Cy LD achieving an ORR of 84% compared to 81% with other LD regimens (p = 0.59) and no difference observed in rates of ≥ VGPR (66% Flu/Cy LD vs 60% other LD; p = 0.48). Of those evaluable for MRD at 1 and 3 months, the MRD negative rate at 10 -6 for those with Flu/Cy LD was 77% (n= 137) and 77% (n=113) and with other LD regimens was 66% (n=35) and 79% (n=28), respectively. At a median follow-up of 9.7 months, no statistically significant difference was noted in median progression free survival (mPFS) with Flu/Cy vs other LD regimens (9.3 mos vs NR) or overall survival (OS) (19.4 mos vs NR). When stratified by type of CAR-T therapy, treatment with bendamustine-based LD was associated with an inferior mPFS compared to those receiving Flu/Cy LD in patients treated with ide-cel (3.8 vs 8.5 mos; p=0.0056), though not by multivariate analysis. Univariate analysis of patients treated with ide-cel between Flu/Cy and bendamustine LD did not reveal any significant differences in age, gender, ECOG, R-ISS stage, extramedullary disease, high-risk cytogenetics or renal dysfunction (Cr < 45 ml/min). LD regimen was not a predictor for PFS on multivariable analyses amongst patients treated with ide-cel, while ECOG ≥ 3 (hazard ratio [HR]= 4.44, 95% confidence interval [CI]= 1.40, 14.08) and t(4,14) (HR= 2.02, 95% CI=1.14, 3.59) were associated with worse PFS. No difference in mPFS by LD regimen was observed in patients receiving cilta-cel, which was a smaller cohort (mPFS: Flu/Cy 11.7 mos, bendamustine-based NR, cladribine-based NR, cyclophosphamide NR). Rates of all grade CRS (81% vs 70%), Grade ≥ 3 CRS (3% vs 3%), all grade ICANS (19% vs 12%, and Grade ≥ 3 ICANS (4% vs 2%) were similar among those receiving Flu/Cy or other LD regimens, respectively. Patients receiving Flu/Cy LD were less likely to have any grade cytopenia at 1 month (33% vs 55%, p < 0.001) and 3 months (52% vs 69%, p < 0.001), with no observed difference in infection rate. Conclusions: The fludarabine shortage experienced in the US in late 2022 necessitated the use of alternative LD regimens with BCMA-directed CAR-T therapy with most centers relying on bendamustine- or cladribine-based regimens. Use of bendamustine-based LD was associated with inferior PFS in patients receiving ide-cel on univariate analysis, but not on multivariate analysis after adjusting for other prognostic factors. In summary, there is no clear difference in efficacy or safety between Flu/Cy and non-Flu/Cy LD in patients receiving BCMA-directed CAR-T therapy. *Authors contributed equally

Background: Autologous CAR-T therapy targeting CD19 is an effective treatment for relapsed or refractory large B-cell lymphoma (LBCL). However, morbidity and mortality related to CAR-T toxicity remain significant concerns. This study aims to evaluate the patterns, risk factors, and implications of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) following CD19-CAR-T therapy in LBCL. Methods: This retrospective analysis includes 1916 LBCL patients treated with CD19-CAR-T cell therapy (axicabtagene-ciloleucel [axi-cel] 75% and tisagenlecleucel 25%) between 2018 and 2020 and reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). Patient demographics, baseline characteristics, treatment-related variables, and clinical outcomes were collected. The incidence, severity and timing of onset of CRS and ICANS (according to median time to onset) were analyzed, factors associated with these outcomes and their impact on overall survival as time dependent covariates were done using Cox Regression multivariate analyses. Results: The median age of the patients was 64 years, with a majority having a Karnofsky performance status (KPS) below 90% (61%) and not receiving bridging therapy (67%). CRS was observed in 75.1% of patients, with 9% experiencing severe CRS (grades ≥ 3). Similarly, 43% of patients experienced ICANS, with 20% having severe ICANS (grade ≥ 3). The median time to toxicity was shorter for CRS (4 days) compared to ICANS (7 days). Nearly all the patients who developed ICANS also experienced CRS (98%; ), and the correlation between these two events and respective severities are shown in the Figure 1a. In the multivariate analyses, factors associated with development of CRS were gender (women, Odds ratio [OR] 1.39, 95% confidence interval [CI] 1.10- 1.76, p=0.006), high LDH at time of infusion (OR 1.56; 95% CI 1.22 - 2.00, p=0.002) and product (axi-cel OR 4.60, 95% CI 3.56 -5.81, p<0.001). Factors associated with the development of ICANS included age (> 65 years, OR 1.83; 1.50-2.24, p<0.001), KPS (<80%, OR 2.48; 1.88-3.27, p<0.001), disease status at infusion (treatment resistant disease, OR 1.98; 1.09-3.58, p=0.024; and untreated relapse OR 2.62, 1.35-5.10, p=0.004) and product (axi-cel, OR 5.85; 4.47-7.64, p<0.0001). Factors associated with severe and early onset CRS and ICANS are listed in the table below. The median follow-up of 14.2 months, the estimated 12-month overall survival, progression-free survival (PFS), and treatment-related mortality were 61.6% (95% CI: 59.4-63.9), 42.2% (39.9-44.5), and 4.3% (3.4-5.3), respectively. Overall CRS, early onset CRS and overall ICANS were not associated with higher mortality, however grade >3 CRS (HR 1.79; 1.41-2.28, p<0.001), grade >3 ICANS (hazard ratio [HR] 1.34; 95% CI 1.13-1.59, p=0.002) and early onset ICANS (<7 days, HR 1.23; 1.05-1.44, p=0.01) were associated with higher mortality. The impact of severe CRS on survival are shown in the landmark analysis at 30 days from infusion in the figure 1B. Conclusion: In the largest analysis of CD19-CAR-T cell therapy toxicities to date, we observed a high burden of CRS and ICANS among LBCL patients. The CAR T cell product type was consistently associated with higher incidence, shorter onset and higher severity of both toxicities. High LDH, older age and low performance score also influence the severity and onset of these outcomes. Additionally, patients who developed higher grades of CRS/ICANS and earlier onset ICANS had a higher mortality, stressing the need to develop novel strategies to mitigate the incidence and optimize management of these patients to improve their outcomes.

Introduction Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 Chimeric Antigen Receptor (CAR) T-cell therapy that induces durable responses in patients with relapsed or refractory large B-cell lymphoma. At a median of 63.1 months follow-up on the ZUMA-1 trial, median overall survival (OS) was 25.8 months with 5-year OS and PFS (progression-free survival) estimates of 42.6% (95% CI, 32.8-51.9) and 31.8% (95% CI, 22.9-41.1), respectively (Neelapu, Blood 2023). We previously reported outcomes of axi-cel patients treated with standard of care therapy, including 42% who did not meet eligibility criteria for ZUMA-1 based on co-morbidities (Nastoupil, JCO 2020). Here we report results from this cohort at a median follow up of 58 months, as well as late outcomes of interest. Results The US Lymphoma CAR-T Consortium is comprised of 17 US academic centers who contributed data independent of the manufacturer. Two hundred and ninety-eight patients underwent leukapheresis with intent to manufacture standard of care axi-cel (n=298) as of September 30, 2018. In infused patients (n=275), OS and PFS were calculated from date of infusion. After a median follow-up of 58 months, median OS was 34.9 months (95% CI 23.4 - 44.8) with the OS at 3, 4, and 5 years of 49.1% (95% CI 42.9 - 54.9%), 43% (95% CI 36.8 - 48.9%), and 40.3% (95% CI 34.2 - 46.4%), respectively. The median PFS was 8.7 months (95% CI 5.87 - 16.6) and the 3-,4-, and 5- year PFS were 36.1% (95% CI 30.4 - 41.8%), 30.7 (95% CI 25.2 - 36.4%), and 28.5% (95% CI 23 - 34.2%), respectively. Results of multi-variable modeling were similar to our prior analysis: male sex (HR 1.56, 95% CI 1.08 - 2.27, p =0.02); LDH above the upper limit of normal (HR 1.6, 95% CI 1.12 - 2.30, p = 0.01); ECOG status of 2-4 (HR 2.02, 95% CI 1.33 - 3.07, p = <0.001); and elevated bilirubin > 1.5 (HR 5.68, 95% CI 2.21 - 14.6, p = <0.001) were associated with decreased OS. Factors associated with decreased PFS included male sex (HR 1.68, 95% CI 1.20 - 2.37, p = 0.003), LDH above the upper limit of normal (HR 1.82, 95% CI 1.31 - 2.53, p = <0.001), ECOG status of 2-4 (HR 1.93, 95% CI 1.30 - 2.86, p = 0.001), elevated bilirubin (HR 3.68, 95% CI 1.45 - 9.37, p = 0.006) and receipt of 3 or more prior lines of therapy (HR 1.49, 95% CI 1.03 - 2.13, p = 0.032). We also assessed events of interest including late PFS events and causes of non-relapse mortality (NRM). One hundred and ninety-one PFS events occurred after axi-cel infusion during the follow-up period, 151 due to lymphoma progression and 40 NRM. In the first 12 months post infusion, 131 progression events occurred,13 between 1 and 2 years post infusion, and 7 relapses after 2 years with the latest occurring 46.4 months after infusion. Thirteen NRM events occurred in the 1st year post infusion, 6 between 1- and 2-years post infusion and 21 occurring later than 2 years after infusion. Of the 40 NRM events, 21 were secondary to infection including fungal infections (n = 3, 2 candidemia, 1 candidemia and pneumocystis jiroveci pneumonia), JC encephalitis (n=1) and COVID-19 (n = 2). Nine deaths were attributed to secondary malignancy. Other causes of NRM included cerebral edema (n=1), HLH (n=1), intracranial hemorrhage (n=1), suicide (n=1), and unknown (n=6). The 5-year cumulative risk of relapse was 55.2% and the 5-year risk of non-relapse mortality was 16.2%. Excluding non-melanoma skin cancers, twenty-three of 275 (8%) patients were diagnosed with subsequent malignancy after axi-cel treatment: 14/275 (5%) patients were diagnosed with myeloid malignancies (MDS (n=11), AML (n=2), CMML (n=1)); other malignancies included anal squamous cell carcinoma (ca) (n=1); histiocytic sarcoma (n=1); prostate ca (n=1); endometrial ca (n=1); lung ca (n=1); merkel cell ca (n = 1), mesothelioma (n=1), B-ALL (n = 1), and AITL (n=1). Conclusion This multi-center retrospective study showed similar 5-year results to the ZUMA-1 trial with a 5-year PFS and OS of 28.5% and 40.3%, despite including patients who did not meet ZUMA-1 eligibility criteria based on comorbidities. Non-relapse mortality was primarily due to infection and secondary malignancy. This report supports the curative potential of axi-cel but highlights the competing risk of NRM in this high-risk patient population.

Introduction: Novel B cell maturation antigen (BCMA) directed therapies including chimeric antigen receptor- T (CART) such as idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel) have been approved since 2021. More recently in 2022, the first BCMA-directed T-cell-engager (TCE), teclistamab (tec), was also approved for the treatment of relapsed/ refractory multiple myeloma (RRMM). Unfortunately, limited access to these therapies worldwide appears to be a major challenge. This study aims to gain insight into the variation in access to these therapies, and barriers to access. Methods: This study was an electronic survey of 176 hematologists/oncologists in centers across the globe outside the USA who treat MM and was conducted in collaboration with US Myeloma Innovations Research Collaborative (USMIRC). The survey was distributed from June 18 th 2023, to July 15 th 2023. Sections included demographics of respondents, availability of drugs in the country, and barriers to access. The respondents categorized each medication as “easily accessible”, “moderately accessible,” “not readily accessible” or “no access”. To categorize a country/region as having “adequate access”, the cut-off was 60% of responders affirming easy/moderately easy access. We investigated whether higher healthcare spending in a country is associated with better drug accessibility. Health expenditure (HE) of a country's Gross domestic product (GDP) from the World Bank was utilized to categorize countries into two groups: “High healthcare investing nations” (HHIN), which included countries spending >10% of their GDP on healthcare, while “Low healthcare investing nations” (LHIN) included countries spending <10% on healthcare. An interim analysis is reported. Results: There were 95 (54%) completed responses from 33 countries. Most (51%) were university-based academic centers and only 17% were centers with a dedicated focus in plasma cell disorders. Only 17% reported adequate access to ide-cel and 16% to cilta-cel, while a limited, yet higher number of respondents had adequate access to tec (23%). Refer to Table 1 Access to CART (ide-cel and cilta-cel): Globally, only 3 of the 33 (9%) countries had access to ide-cel, cilta-cel or both (France, Morocco, Saudi-Arabia). All other countries had limited access. When grouped by continent, none of the continents had adequate access to CART. Both HHIN and LHIN countries had limited access to CART. Access to TCE (tec): Seven of the 33 (21%) countries had adequate access to tec (Switzerland, Netherlands, France, Portugal, Czech Republic, Morrocco, Saudi Arabia). All other countries had limited access. When grouped by continent, although Europe had the most access, none of the continents had adequate access to TEC. Both HHIN and LHIN countries had limited access to TCE, although relatively, TEC was more accessible compared to CART. Figure 1 summarizes access to CART and TCE Barriers to access: Other than Europe, the most common barrier for ide-cel, cilta-cel and tec was cited as financial burden for patients. Financial burden for patients as a top barrier for each of the products by continent was as follows: Asia (83%), South America (64%), Africa (71%) Australia (100%), and North America (100%). In Europe, for CART, financial burden remained a top barrier (50%) along with local agency approval (50% for ide-cel, 44% for cilta-cel). In Europe, the most cited barrier for TCE was the financial burden for patients (44%), while (33%) of oncologists reported no barrier to TCE. Reimbursement for CART and TCE in Europe requires phase 3 randomized controlled trial data, which is just emerging since 2022 for CART and relatively increased access may be due to the presence of compassionate use programs. Conclusion : The survey is the first attempt to highlight the significantly limited global access to novel therapies (ide-cel, cilta-cel, and tec) for the treatment of RRMM. All continents including HHIN had limited access to CART and TCE. Noticeably, CART is less accessible than TCE, even though approved earlier. The main barrier to both CART and TCE is reported as financial burden for patients. USMIRC in collaboration with oncologists worldwide, global agencies, governments, regulatory agencies, policymakers and industry partners, is planning to further explore restrictions to access to CART and TCE and strategies to overcome these barriers.

Abstract Idecabtagene vicleucel (ide-cel) was the first chimeric antigen receptor T-cell therapy to gain US Food and Drug Administration approval for patients with relapsed/refractory multiple myeloma (RRMM). The clinical outcomes of standard of care (SOC) ide-cel in racially and ethnically diverse populations have been understudied. This study pooled data from 207 patients with RRMM (28% patients of racial and ethnic minority groups) treated with SOC ide-cel across 11 institutions to examine racial and ethnic differences in the incidence of toxicities and adverse events, response to ide-cel, and survival. This study included 22 (11%) Hispanic, 36 (17%) non-Hispanic Black, and 149 (72%) non-Hispanic White patients with RRMM. Compared with Hispanic and non-Hispanic White patients, non-Hispanic Black patients had higher median levels of C-reactive protein (1.0, 0.8, and 3.5 mg/dL, respectively; P = .02) and baseline ferritin (362.0 vs 307.0 vs 680.5, respectively; P = .08) and were more likely to develop cytokine release syndrome (77%, 85%, and 97%, respectively; P = .04). Although best overall response rate was lower among Hispanic patients (59%) than among non-Hispanic Black (86%) and White patients (86%; P = .01), there were no racial and ethnic differences in progression-free or overall survival. We provide, to our knowledge, the first and largest investigation of clinical outcomes of SOC ide-cel by race and ethnicity. Despite differences in safety and response to ide-cel, our findings encourage the use of ide-cel in all patients with RRMM. These findings should be confirmed in larger samples of diverse patients with RRMM, with longer follow-up time.

AbstractCheckpoint inhibitor (CPI) therapy with anti–PD-1 antibodies has been associated with mixed outcomes in small cohorts of patients with relapsed aggressive B-cell lymphomas after CAR-T failure. To define CPI therapy efficacy more definitively in this population, we retrospectively evaluated clinical outcomes in a large cohort of 96 patients with aggressive B-cell lymphomas receiving CPI therapy after CAR-T failure across 15 US academic centers. Most patients (53%) had diffuse large B-cell lymphoma, were treated with axicabtagene ciloleucel (53%), relapsed early (≤180 days) after CAR-T (83%), and received pembrolizumab (49%) or nivolumab (43%). CPI therapy was associated with an overall response rate of 19% and a complete response rate of 10%. Median duration of response was 221 days. Median progression-free survival (PFS) and overall survival (OS) were 54 and 159 days, respectively. Outcomes to CPI therapy were significantly improved in patients with primary mediastinal B-cell lymphoma. PFS (128 vs 51 days) and OS (387 vs 131 days) were significantly longer in patients with late (>180 days) vs early (≤180 days) relapse after CAR-T. Grade ≥3 adverse events occurred in 19% of patients treated with CPI. Most patients (83%) died, commonly because of progressive disease. Only 5% had durable responses to CPI therapy. In the largest cohort of patients with aggressive B-cell lymphoma treated with CPI therapy after CAR-T relapse, our results reveal poor outcomes, particularly among those relapsing early after CAR-T. In conclusion, CPI therapy is not an effective salvage strategy for most patients after CAR-T, where alternative approaches are needed to improve post–CAR-T outcomes.

PURPOSE Brexucabtagene autoleucel (brexu-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for relapsed/refractory mantle cell lymphoma (MCL). This therapy was approved on the basis of the single-arm phase II ZUMA-2 trial, which showed best overall and complete response rates of 91% and 68%, respectively. We report clinical outcomes with brexu-cel in the standard-of-care setting for the approved indication. PATIENTS AND METHODS Patients who underwent leukapheresis between August 1, 2020 and December 31, 2021, at 16 US institutions, with an intent to manufacture commercial brexu-cel for relapsed/refractory MCL, were included. Patient data were collected for analyses of responses, outcomes, and toxicities as per standard guidelines. RESULTS Of 189 patients who underwent leukapheresis, 168 (89%) received brexu-cel infusion. Of leukapheresed patients, 79% would not have met ZUMA-2 eligibility criteria. Best overall and complete response rates were 90% and 82%, respectively. At a median follow-up of 14.3 months after infusion, the estimates for 6- and 12-month progression-free survival (PFS) were 69% (95% CI, 61 to 75) and 59% (95% CI, 51 to 66), respectively. The nonrelapse mortality was 9.1% at 1 year, primarily because of infections. Grade 3 or higher cytokine release syndrome and neurotoxicity occurred in 8% and 32%, respectively. In univariable analysis, high-risk simplified MCL international prognostic index, high Ki-67, TP53 aberration, complex karyotype, and blastoid/pleomorphic variant were associated with shorter PFS after brexu-cel infusion. Patients with recent bendamustine exposure (within 24 months before leukapheresis) had shorter PFS and overall survival after leukapheresis in intention-to-treat univariable analysis. CONCLUSION In the standard-of-care setting, the efficacy and toxicity of brexu-cel were consistent with those reported in the ZUMA-2 trial. Tumor-intrinsic features of MCL, and possibly recent bendamustine exposure, may be associated with inferior efficacy outcomes.