Olson, Amanda L

Abstract The cumulative impact of baseline comorbidities on outcomes of chimeric antigen receptor T-cell (CAR-T) therapy is not well established. Therefore, we developed and validated a Cellular Therapy Comorbidity Index (CT-CI) to predict outcomes following CD19-directed CAR-T therapy for large B-cell lymphoma (LBCL). Patients aged 18 or older receiving commercial CAR-T therapy for LBCL during 2017 to 2020 were selected from the Center for International Blood and Marrow Transplant Research registry. Patients were randomly assigned to training or validation cohorts. Comorbidities given weighted scores comprised the CT-CI, which was then validated for overall survival (OS) prognostication. A total of 1916 patients from 97 medical centers were included, with a median age of 64 years (19-91 years). About 70% of patients had comorbidities, such as cardiac disease (12%); diabetes (14%); hepatic dysfunction (mild, 8%; moderate to severe, 2%); psychiatric disturbance (18%); and pulmonary dysfunction (moderate, 15%; severe, 12%). The CT-CI was calculated, stratified patients in 3 categories, and was associated with increased mortality. Patients with higher CT-CI scores had worse OS (CT-CI 1: hazard ratio [HR], 1.37 [95% confidence interval [CI], 1.16-1.62; P< .001]; CT-CI 2: HR, 1.49 [95% CI, 1.17-1.89; P = .001]; CT-CI ≥ 3: HR, 2.55 [95% CI, 1.90-3.42; P< .001]). Higher CT-CI scores predicted treatment-related mortality and relapse. There was no correlation between the CT-CI score and CAR-T–related toxicities. The novel CT-CI score stratifies the effect of patient comorbidities on survival after CAR-T therapy and can be used for clinical decision-making and treatment selection in high-risk populations. However, comorbidities and fear of increased toxicity should not preclude patients from this effective therapy.

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: Axi-cel utilization expanded after demonstration of superior event-free survival in patients (pts) with early relapsed or primary refractory LBCL (Locke, et al. NEJM. 2022) and was reinforced by improved overall survival (OS) among these pts (Westin, et al. NEJM. 2023). Despite increased demand, limited data exist on the impact of bridging therapies (BT) on pt outcomes. Thus, BT use between leukapheresis and lymphodepletion (LD) is largely at the discretion of treating physicians. Here, we assessed the impact of BT on effectiveness and safety outcomes after axi-cel. Methods: Pts receiving axi-cel for 3L+ LBCL in the US between 2017-2020 were prospectively collected through the CIBMTR registry in a post-authorization safety study; data up to May 2023 were included. Effectiveness outcomes were overall response rate (ORR), complete response (CR) rate, duration of response (DOR), progression-free survival (PFS), and OS. Safety outcomes were cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) per ASTCT grading, non-relapse mortality (NRM), and other key adverse events. Propensity score-based inverse probability of treatment weighting (IPTW) was used in logistic and Cox regressions to account for potential confounding in BT use. For pts who had BT, effects of BT types and responses on outcomes were evaluated using conventional logistic and Cox regressions. Results: Of 1497 pts registered, 1307 had BT data available and were included (median follow-up, 36 mo). Overall, 430 pts (33%) received BT (median time from leukapheresis to LD, 23 days [IQR, 21-28]). Systemic therapy was used in 403 pts (31%), including 305 (23%) with chemotherapy (CT)-based BT (19% treated with CT + anti-CD20 monoclonal antibody [mAb; mainly rituximab] and 4% with CT only), and 98 (7%) with non-CT systemic therapy (Table). Radiotherapy (± systemic therapy) was used in 44 pts (3%). Pts with ≥3 lines of prior therapy (odds ratio [OR], 10.67 [95% CI, 7.17−15.87]) or mild hepatic impairment prior to infusion (OR, 1.64 [1.06−2.55]) were more likely to receive BT, while those with histologic transformation (OR, 0.69 [0.51−0.92]) or longer time from diagnosis to leukapheresis were less likely to receive BT. ORRs to axi-cel were 70% and 79% (CR rates 51% and 64%) for pts with or without BT, respectively. Unadjusted DOR, PFS, and OS at 3 years were 40%, 28%, and 37%, respectively, in pts with BT vs 49%, 39%, and 49%, respectively, in those without BT. After multivariate adjustment, no statistical significance was found between BT and any effectiveness outcome. Adjusted hazard ratios (HRs) for BT were 1.13 (95% CI, 0.94-1.36) for PFS and 1.11 (95% CI, 0.92-1.34) for OS, respectively (Figure). Most safety endpoints were consistent regardless of BT. Grade ≥3 CRS and ICANS occurred in 12% and 30% of pts, respectively, who received BT vs 10% and 24% of pts who did not. Use of BT was associated with more frequent prolonged neutropenia (OR, 2.24 [1.44-3.50]) and thrombocytopenia (OR, 2.33 [1.67-3.24]), but not associated with a higher rate of infections or NRM (Table). Among pts receiving BT, 74 (17%) had a CR or partial response to BT. Of them, median PFS and median OS post infusion were 12.7 mo (3.8-not estimable [NE]) and 48.7 mo (18.6-NE), respectively. Response to BT was associated with increased CR rate (OR, 2.00 [1.07-3.75]), PFS (HR, 0.69 [0.49-0.99]), and OS (HR, 0.59 [0.40-0.88]) and decreased any-grade ICANS (OR, 0.51 [0.29-0.92]). When different BT strategies were considered, effectiveness and most safety outcomes for CT + anti-CD20 mAb vs non-CT treatment were comparable without significant difference. CT + anti-CD20 mAb was associated with improved ORR (OR, 1.90 [1.00-3.60]), PFS (HR, 0.69 [0.49-0.98]), and OS (HR, 0.66 [0.46-0.95]) but increased any-grade CRS (OR, 2.16 [1.02-4.57]) vs CT only. CT use was associated with an increased risk of prolonged thrombocytopenia (41% vs 24% for pts receiving non-CT treatment; OR, 2.37 [1.39-4.02]). No significant association was found between use of radiotherapy as BT and any outcome. Conclusion: These US real-world findings suggest that the addition of BT prior to axi-cel is associated with more frequent prolonged cytopenias but does not impact effectiveness or other critical safety outcomes. Response to BT may prognosticate more favorable outcomes after axi-cel infusion. Further study is warranted to identify the optimal bridging regimen.