CAR-HEMATOTOX: A model for CAR T-cell related hematological toxicity in relapsed/refractory large B-cell lymphoma

Myeloid neoplasms after CD19-directed CAR T cells therapy in long-term B-cell lymphoma responders, a rising risk over time?

Therapy-related myeloid neoplasms (t-MN), including myelodysplastic neoplasms (t-MDS) and acute myeloid leukemia (t-AML), have emerged as significant late complications after CAR T cell therapy. We retrospectively analyzed 539 patients with B cell lymphoma treated with CD19 directed CAR T cell therapy across four French centers. Cumulative incidences of t-MN was estimated with relapse or death treated as competing risk. Univariate and propensity score matching (PSM) analyses were conducted to assess risk factors with age and the number of prior treatments as covariates. After a median follow-up of 25 months, the cumulative incidence of t-MN was 4.5% at 2 years. T-MN occurred predominantly as t-MDS (62%) and t-AML (38%) with high cytogenetic risk. Median overall survival after t-MN diagnosis was 4.5 months. In univariate analysis, older age (p < 0.01), higher MCV (p < 0.01), and higher ICANS grade (p = 0.04) were associated with increased risk of t-MN. After PSM, MCV and ICANS grade remained significant risk factors. CAR T cell products with CD28 co-stimulatory domains trended towards higher t-MN risk (p = 0.09). NGS analysis showed that 85.7% of t-MN had pre-existing mutations, most commonly TP53. This study highlights t-MN as a severe late complication of CAR T cell therapy. MCV and ICANS grade were identified as key risk factors.

CAR T cells in autoimmunity: game changer or stepping stone?

ABSTRACT

The advent of chimeric antigen receptor (CAR) T cells has revolutionized the treatment landscape for hematologic malignancies, and emerging evidence suggests their potential in autoimmune diseases (AIDs). This article evaluates the early successes and future implications of B-cell-targeting CAR T-cell therapy in AIDs. Initial applications, particularly in refractory systemic lupus erythematosus, have demonstrated significant and durable clinical remissions, with accompanying evaluation of the immune system suggesting a so-called "reset" of innate inflammation and adaptive autoimmunity. This has generated widespread interest in expanding this therapeutic approach. CAR T cells offer unique advantages over other treatment modalities, including very deep B-cell depletion and unique therapeutic activity within inflamed tissues and associated lymphoid structures. However, the field must address key concerns, including long-term toxicity, particularly the risk of secondary malignancies, and future accessibility given the higher prevalence of AIDs compared with malignancies. Technological advances in cell therapy, such as next-generation CAR T cells, allogeneic off-the-shelf products, and alternative cell types, such as regulatory CAR T cells, are being explored in AIDs to improve efficacy and safety. In addition, bispecific antibodies are emerging as potential alternatives or complements to CAR T cells, potentially offering comparable efficacy without the need for complex logistics, lymphodepletion, and the risk of insertional mutagenesis. As the field evolves, cellular therapists will play a critical role in the multidisciplinary teams managing these complex cases. The transformative potential of CAR T cells in AIDs is undeniable, but careful consideration of safety, efficacy, and implementation is essential as this novel therapeutic approach moves forward.

CAR-T for multiple myeloma: practice pearls

The CAR-T cell products ciltacabtagene autoleucel and idecabtagene vicleucel have transformed the management of patients with multiple myeloma. Here, we present a practical guide highlighting clinical pearls on the incorporation of CAR-T into clinical practice. Topics addressed include expected outcomes, recommendations for referral timing, bridging therapy, treatment complications, therapeutic sequencing, and management of relapse.

Semiquantitative PET Parameters Refine Prognosis in CAR T-Treated Lymphoma After 1 and 3 Months: A Prospective Single-Center Study

Chimeric antigen receptor T-cell (CAR T) therapy has shown remarkable efficacy in treating relapsed or refractory large B-cell lymphoma. However, for nearly half of these patients, the therapy eventually does not achieve durable remission. We investigated whether semiquantitative PET parameters (namely, SUVmax, metabolic tumor volume [MTV], and total lesion glycolysis [TLG]) could improve risk stratification 1 mo (PET1m) and 3 mo (PET3m) after CAR T infusion. Methods: In this prospective, single-center cohort study, patients with large B-cell lymphoma received axicabtagene ciloleucel or tisagenlecleucel. [18F]FDG PET/CT scans were acquired at baseline, 1 mo, and 3 mo after infusion. MTV and TLG were calculated using a threshold SUVmax of 4 or greater. Patients were followed for overall survival (OS), progression-free survival (PFS), and duration of response (DoR). The imaging assessment was based on the Lugano recommendation for response assessment. Prognostic factors were identified using univariate and multivariate Cox regression. Results: Sixty-one patients were enrolled, with a median follow-up of 18 mo. Twenty-eight (46%) patients died. Kaplan-Meier analysis with log-rank tests indicated a significant association of elevated Deauville score (DS), SUVmax, MTV, and TLG with OS (all P < 0.05). DS cutoff was arbitrarily fixed at 4. The optimal SUVmax, MTV, and TLG cutoffs at PET1m were 9.1, 60.8, and 97.0, respectively; whereas at PET3m, they were 6.3, 120.1, and 436.9, respectively. Patients with an SUVmax of 6.3 or greater at PET3m had an 8-fold increase in risk of death (hazard ratio [HR], 8.15; 95% CI, 2.81-23.6; P < 0.01) compared with those below this cutoff. Similarly, higher MTV (≥120.1) at PET3m yielded a nearly 10-fold risk (HR, 9.87; 95% CI, 3.65-26.7; P < 0.01). DS, SUVmax, MTV, and TLG at both PET1m and PET3m were associated with OS and PFS (all P < 0.05), whereas PET3m parameters also correlated with DoR (P < 0.05). Harrell C-index values were higher for PET3m measures than for PET1m, though differences were not statistically significant (P > 0.05). On multivariable analysis, older age (HR, 1.10), bridging therapy (HR, 10.91), elevated lactate dehydrogenase (HR, 6.43), increased fibrinogen (HR, 5.27), and higher SUVmax at PET3m (HR, 11.03) independently predicted poorer OS. There were no significant associations between SUVmax, MTV, and TLG with CAR T-related toxicities. Conclusion: Semiquantitative PET parameters, such as SUVmax, MTV, and TLG, at 1 mo and 3 mo after CAR T-cell therapy correlate significantly with OS, PFS, and DoR. [18F]FDG PET/CT at 3 mo may offer slightly stronger prognostic discrimination, but both time points can be used for early risk stratification.

Neurotoxic complications of chimeric antigen receptor (CAR) T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy has revolutionised the treatment of haematological malignancies and has demonstrated efficacy in early trials for solid tumours, neurological and rheumatological autoimmune diseases. However, CAR-T is complicated in some patients by neurotoxicity syndromes including immune-effector cell-associated neurotoxicity syndrome, and the more recently described movement and neurocognitive treatment-emergent adverse events, and tumour inflammation-associated neurotoxicity. These neurotoxic syndromes remain poorly understood and are associated with significant morbidity and mortality. A multidisciplinary approach, including neurologists, haematologists and oncologists, is critical for the diagnosis and management of CAR-T neurotoxicity. This approach will be of increasing importance as the use of CAR-T expands, its applications increase and as novel neurotoxic syndromes emerge.

Odronextamab monotherapy in R/R DLBCL after progression with CAR T-cell therapy: primary analysis of the ELM-1 study

ABSTRACT

Patients with relapsed/refractory diffuse large B-cell lymphoma progressing after chimeric antigen receptor T-cell (CAR-T) therapy have dismal outcomes. The prespecified post-CAR-T expansion cohort of the ELM-1 study investigated the efficacy and safety of odronextamab, a CD20×CD3 bispecific antibody, in patients with disease progression after CAR-Ts. Sixty patients received IV odronextamab weekly for 4 cycles followed by maintenance until progression. The primary end point was objective response rate (ORR) by independent central review. The median number of prior lines of therapy was 3 (range, 2-9), 71.7% were refractory to CAR-Ts, and 48.3% relapsed within 90 days of CAR-T therapy. After a median follow-up of 16.2 months, ORR and complete response (CR) rate were 48.3% and 31.7%, respectively. Responses were similar across prior CAR-T products and time to relapse on CAR-T therapy. Median duration of response was 14.8 months and median duration of CR was not reached. Median progression-free survival and overall survival were 4.8 and 10.2 months, respectively. The most common treatment-emergent adverse event was cytokine release syndrome (48.3%; no grade ≥3 events). No cases of immune effector cell-associated neurotoxicity syndrome were reported. Grade ≥3 infections occurred in 12 patients (20.0%), 2 of which were COVID-19. Odronextamab monotherapy demonstrated encouraging efficacy and generally manageable safety, supporting its potential as an off-the-shelf option for patients after CAR-T therapy. This trial was registered at www.clinicaltrials.gov as #NCT02290951.

Talicabtagene autoleucel for relapsed or refractory B-cell malignancies: results from an open-label, multicentre, phase 1/2 study

BACKGROUND

In low-income and middle-income counties (LMICs), the outcome of relapsed or refractory B-cell malignancies is poor due to the absence of effective therapies. We report the results of a phase 1/2 study of a novel humanised anti-CD19 4-1BB chimeric antigen receptor (CAR) T-cell therapy, talicabtagene autoleucel, for patients with relapsed or refractory B-cell malignancies.

METHODS

This open-label, multicentre, phase 1/2 study was done at six tertiary cancer centres in India. Phase 1 was a single-centre study done in Tata Memorial Hospital, India, in patients aged 18 years or older with relapsed or refractory B-cell lymphomas. Phase 2 was a single-arm, multicentre, basket trial done in five tertiary cancer centres in patients aged 15 years and older with relapsed or refractory B-cell acute lymphoblastic leukaemia or B-cell lymphoma. Eligible patients had a life expectancy of 12 weeks or more, an ECOG performance status of 0-1 (phase 1) or 0-2 (phase 2), and an adequate organ function. Patients underwent apheresis to obtain at least 1 × 109 lymphocytes to manufacture CAR T cells. Lymphodepletion therapy was done with cyclophosphamide 500 mg/m2 and fludarabine 30 mg/m2 for 3 days or bendamustine 90 mg/m2 for 2 days. Patients were then infused intravenously with talicabtagene autoleucel 1 × 107-5 × 109 CAR T cells in a fractionated schedule (10%, 30%, and 60%, on days 0, 1, and 2, respectively) during phase 1 or at least 5 × 106 CAR T cells per kg (up to 2 × 109 CAR T cells) on day 0 during phase 2. The primary endpoints were safety (phase 1) and overall response rate (phase 2). The efficacy analysis was done in the efficacy evaluable cohort (all patients who received the target dose and 3 days of lymphodepletion therapy). The safety analysis was done in the safety population (all patients who received talicabtagene autoleucel). The trials are registered with Clinical Trial Registry-India (CTRI/2021/04/032727 and CTRI/2022/12/048211), and enrolment is closed.

FINDINGS

Of 64 patients, 14 were enrolled in phase 1 (from May 11, 2021, to May 13, 2022) and 50 were enrolled in phase 2 (Dec 27, 2022, to Aug 31, 2023). The median age of the overall cohort was 44 years (IQR 27-57), and 49 (77%) of 64 patients were male and 15 (23%) were female. In phase 1, no dose-limiting toxicities occurred at doses of 2 × 106-17 × 106 CAR T cells per kg. A dose of at least 5 × 106 CAR T cells per kg was chosen for phase 2 based on a complete response in three of seven patients at this dose. The most common grade 3 or worse toxicities were haematological events: anaemia (35 [61%] of 57 patients), thrombocytopenia (37 [65%] patients), neutropenia (55 [96%] patients, and febrile neutropenia (27 [47%]) patients). There were two treatment-related deaths, one due to febrile neutropenia, immune-effector cell associated haemophagocytic lymphohistiocytosis, and septic shock, and the second due to pulmonary bleed, multiorgan dysfunction syndrome, and cytokine release syndrome. In 51 efficacy-evaluable patients (36 with B-cell lymphoma and 15 with B-cell acute lymphoblastic leukaemia), the overall response rate was 73% (37 of 51; 95% CI 59-83).

INTERPRETATION

Talicabtagene autoleucel had a manageable safety profile and induced durable responses in patients with relapsed or refractory B-cell malignancies. This therapy addresses an important unmet need for patients with relapsed or refractory B-cell malignancies in India.

FUNDING

Immunoadoptive Cell Therapy (ImmunoACT) and Indian Council of Medical Research (ICMR).

Natural killer cells: a new promising source for developing chimeric antigen receptor anti-cancer cells in hematological malignancies

In recent times, the application of CAR-T cell treatment has significantly progressed, showing auspicious treatment outcomes in hematologic malignancies. However, along with these advances, certain limitations and challenges hurdle the widespread utilization of this technology. Recently, CAR-NK cells have gained attention in cancer treatment, as this approach has an important advantage over CART therapy (i.e. no need for HLA matching) for targeting foreign cells. This review aims to explore the benefits of CAR NK cell therapy, and generation strategies, as well as the challenges and limitations hindering the application of CAR NK cells in experimental studies and trials on hematologic malignancies.

An inflammatory biomarker signature of response to CAR-T cell therapy in non-Hodgkin lymphoma

Disease progression is a substantial challenge in patients with non-Hodgkin lymphoma (NHL) undergoing chimeric antigen receptor T cell (CAR-T) therapy. Here we present InflaMix (INFLAmmation MIXture Model), an unsupervised quantitative model integrating 14 pre-CAR-T infusion laboratory and cytokine measures capturing inflammation and end-organ function. Developed using a cohort of 149 patients with NHL, InflaMix revealed an inflammatory signature associated with a high risk of CAR-T treatment failure, including increased hazard of death or relapse (hazard ratio, 2.98; 95% confidence interval, 1.60-4.91; P < 0.001). Three independent cohorts comprising 688 patients with NHL from diverse treatment centers were used to validate our approach. InflaMix consistently and reproducibly identified patients with a higher likelihood of disease relapse and mortality, and it provided supplementary predictive value beyond established prognostic markers, including tumor burden. Moreover, InflaMix exhibited robust performance in cases with missing data, maintaining accuracy when considering only six readily available laboratory measures. These findings show that InflaMix is a valuable tool for point-of-care clinical decision-making in patients with NHL undergoing CAR-T therapy.

Utility of Thrombopoietin Receptor Agonists for Prolonged Thrombocytopenia After Chimeric Antigen Receptor T-cell Therapy

Chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the treatment landscape for various hematological malignancies. However, it is associated with a range of hematologic complications, including severe and often prolonged thrombocytopenia. Currently, there are no known effective preventative or management measures against CAR-T-induced thrombocytopenia. At the University of Chicago Medical Center, thrombopoietin receptor agonists (TPO-RAs) eltrombopag and romiplostim have been utilized intermittently, per attending preference, in patients post CAR-T treatment presenting with prolonged thrombocytopenia (platelets <50 × 103 cells/μL for at least 14 days). However, whether these treatments yield positive outcomes in this context remains uncertain. This study aims to evaluate the efficacy and safety of TPO-RAs in patients with CAR-T-induced thrombocytopenia. The primary objective is to compare the incidence of platelet recovery (defined as two consecutive platelet counts of ≥50 × 103 cells/μL) in patients who received TPO-RAs versus those who did not for CAR-T-associated prolonged thrombocytopenia between January 1, 2018, and June 30, 2023. The secondary objectives include time to platelet recovery, incidence of clinically relevant bleed, hospital length of stay, incidence of adverse effects associated with TPO-RA administration, overall survival, and financial toxicity. This is a single-center, retrospective study conducted at the University of Chicago Medical Center. Eighty-five patients with prolonged, CAR-T-induced thrombocytopenia were enrolled in the study; 12 of these patients were managed with TPO-RA therapy while the remaining 73 received supportive care. Statistical analysis was performed using STATA, incorporating the Chi-squared test for nominal data and the Wilcoxon Rank-sum test for continuous data. A P value of <.05 was used to determine statistical significance. The incidence of platelet recovery was similar between the two groups; in the supportive care group, 53 patients (73%) experienced resolution of thrombocytopenia, compared to 9 patients (75%) in the TPO-RA treated group (P = 1.0). The median time to thrombocytopenia resolution was 56 days in the TPO-RA-treated group and 41 days in those not managed with TPO-RAs (P = .14). The median time to TPO-RA initiation postinfusion was 45 days. There were no statistically significant differences in incidence of clinically relevant bleed or readmission within 1 year of CAR-T infusion between the two groups, but 25% of patients receiving TPO-RA therapy experienced associated arthralgia requiring treatment modification. Additionally, the median cost of a course of eltrombopag was estimated at $86,921.52 per patient at the reported average wholesale price. While TPO-RAs represent a theoretical therapeutic option for CAR-T patients based on their role in chemotherapy-induced thrombocytopenia, our study showed that their use did not provide significant clinical benefit compared to the supportive care approaches. Therefore, without larger, randomized, prospective trials, we are unable to recommend TPO-RA use in this setting, given the current lack of demonstrated efficacy, potential adverse effects, and concerns regarding financial impact.

Prospective Validation of CAR-HEMATOTOX and a Simplified Version Predict Survival in Patients with Large B-Cell Lymphoma Treated with Anti-CD19 CAR T-Cells: Data from CART-SIE Study

BACKGROUND

Anti-CD19 CAR T-cells have revolutionized outcomes in relapsed/refractory large B-cell lymphomas. Long-term follow-up underscored the role of hematological toxicity in nonrelapse mortality, largely driven by infections, leading to the development of the CAR-HEMATOTOX (HT) score for predicting neutropenia. The European scientific community (EHA/EBMT) later reached a consensus, defining a new entity: immune effector cell-associated hematotoxicity (ICAHT).

AIMS

To validate the ability of the HT score to predict ICAHT and survival.

METHODS

The CART-SIE is an ongoing multicenter prospective observational study collecting data on patients affected by B-cell lymphoma treated with commercial anti-CD19 CAR T-cells (ClinicalTrials.gov ID: NCT06339255).

RESULTS

Since 2019 to 2024, 1002 consecutive patients were enrolled. Out of 746 patients infused, the HT score at infusion was evaluable in 389. Median age was 59 years (48-66). Patients with high HT score had greater disease burden and a greater need for bridge therapy. Patients with a HTHIGH score had a 4-fold higher risk of experiencing late ICAHT of grade≥3 (OR = 3.99, 95% CI = 1.16-13.77, P = .03). Patients with a HTHIGH score also showed lower overall response rates (ORR) and complete response rates (CRR) at 90 days (CRR at 90 days: 59% HTLOW versus 38% HTHIGH, OR = 0.42, 95% CI = 0.27-0.66, P = .0002; ORR at 90 days: 67% HTLOW versus 49% HTHIGH, OR = 0.47, 95% CI = 0.29-0.74, P = .001). Adjusted logistic models confirmed that the effect of HT score was independent from baseline characteristics. With a median follow-up of 18 months, patients with a HTHIGH score have lower OS and PFS (1-year OS: 78% HTLOW versus 62% HTHIGH, P = .0002; 1-year PFS: 49% versus 39%, P = .003). Adjusted Cox models confirmed that HT was an independent prognostic factor for OS. A high HT-score was found to be associated with higher risk of secondary primary malignancy (HR=2.8, 95% CI = 1.03-7.8, P = .04). A simplified version of HT (simpleHT), based solely on the platelet count and C-reactive protein at infusion, was calculated for 560 patients and proved significant in predicting both OS and PFS (1-year was 72% simpleHTLOW versus 37% simpleHTHIGH, P < .0001, 1-year PFS was 48% simpleHTLOW versus 22% simpleHTHIGH, P < .0001).

CONCLUSION

In our prospective real-world study, we validated the ability of the HT score to predict ICAHT and survival. SimpleHT identified a population at very high risk with an impaired progression free and overall survival.

Treatment failure patterns in early versus late introduction of CAR T-cell therapy in large B-cell lymphoma

CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy has recently been approved as second-line treatment for relapsed/refractory large B-cell lymphoma (LBCL). This study compares patterns of disease relapse and progression across patients receiving CAR-T as second-line (early administration) versus third or subsequent lines (late administration). We analyzed 354 patients treated with Axicabtagene ciloleucel (71%) and Lisocabtagene maraleucel (29%); 80 (23%) received early administration, and 274 (77%) late administration. One-year overall survival was higher in the early group (82% [95% CI 72-93] vs. 71% [95% CI 66-77], p = 0.048). However, the survival benefit was not sustained in multivariable Cox regression modeling and propensity score matching. One-year cumulative incidences of relapse were similar (37% [95% CI 24-50] vs. 43% [95% CI 37-49], p = 0.2), as were 1-year progression-free survival probabilities (62% [95% CI 50-76] vs. 50% [95% CI 44-57], p = 0.14). The early group exhibited a favorable toxicity profile, with lower rate of grade ≥2 cytokine release syndrome (26% vs. 39%, p = 0.031) and reduced cumulative incidence of severe neutropenia (41% [95% CI 30-52] vs. 55% [95% CI 49-60], p = 0.027). Our results indicate favorable outcomes with CAR-T irrespective of treatment line. The equivalence in disease control suggests that CAR-T resistance mechanisms persist in LBCL failing first-line therapy.

Outcome correlates of approved CD19-targeted CAR T cells for large B cell lymphoma

CD19-targeted chimeric antigen receptor (CAR) T cells have provided a breakthrough in the treatment of patients with relapsed and/or refractory large B cell lymphoma (LBCL). Currently, three CD19-targeted CAR T cell products are approved by the FDA and various other regulators for the treatment of patients with LBCL: axicabtagene ciloleucel, tisagenlecleucel and lisocabtagene maraleucel. Response rates following infusion of these CD19-targeted CAR T cells have been promising; however, approximately half of treated patients show relapse within 2 years. Furthermore, receiving these agents can be associated with serious toxicities, including cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome. In this Review, we summarize the factors associated with the efficacy, including response and survival outcomes, and toxicity of CD19-targeted CAR T cells in pivotal clinical trials and large real-world datasets describing the outcomes of patients with LBCL who received treatment with these products.

Clinical Impact of CD19 Expression Assessed by Quantitative PCR in Lymphoma Patients Undergoing CAR-T Therapy

Introduction

Current guidelines do not mandate CD19 tumor expression assessment before chimeric antigen receptor T-cell (CAR-T) therapy in large B-cell lymphoma (LBCL) patients due to limitations of immunohistochemistry (IHC) or flow cytometry. Quantitative polymerase chain reaction (qPCR) offers a more sensitive alternative for detecting CD19 expression, with the primary advantage that mRNA can be easily extracted from paraffin-embedded tissues.

Methods & Results

In our study, we included 51 adult patients with LBCL treated with axicabtagene ciloleucel. Among them, 16 were classified as CD19-negative by IHC; however, qPCR reclassified six (37.5%) as CD19-positive. We then compared the outcomes between consistently CD19-negative (IHC-qPCR-) and CD19-positive (IHC+ and IHC-qPCR+) patients. CD19-negative cohort showed worse 1-year progression-free survival (15 vs. 45%, p = 0.044) and a trend toward shorter duration of response (29 vs. 55%, p = 0.065). Only one (10%) of the CD19-negative patients remained alive and disease-free at last follow-up (6 months), having previously responded to bridge therapy.

Discussion

If confirmed in a large patient cohort, these findings could form the basis for modifying current patient selection criteria. Consistently negative patients may be suboptimal candidates for anti-CD19 CAR-T therapy. Alternative therapeutic options, such as bispecific antibodies or polatuzumab-based regimens, could be considered for this subset of patients.

Prolonged Cytopenia with CAR-T Cell Therapy and Management Recommendations

Chimeric antigen receptor T-cell (CAR T-cell) therapy has revolutionized the treatment of lymphoid malignancies. Prolonged cytopenias, though poorly understood, have emerged as important considerations in the treatment process. In this review, we classified cytopenias into early (< 30 days post CAR T infusion), and late-occurring (after day 30 post infusion). We identified previous chemotherapy and lymphodepletion chemotherapy as the major risk factors contributing to early cytopenia. Product characteristics, such as costimulatory domains, and side effects of therapy such as cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS) were identified as contributing factors to prolonged cytopenias occurring more than 30 days post CAR-T infusion. We recommend close monitoring with frequent checks, enhanced care with granulocyte colony stimulating factor (GCSF) support for grade 3-4 neutropenia, blood transfusion for severe anemia (Hb < 7g/dL), platelets for severe thrombocytopenia (< 10,000/µL) and thrombopoietin (TPO) mimetics such as eltrombopag or romiplostim for prolonged severe thrombocytopenia in patients at high-risk of hemorrhagic complications.

Mitigation and Management of Common Toxicities Associated with the Administration of CAR-T Therapies in Oncology Patients

Chimeric antigen receptor T-cell (CAR-T) therapies are one of the main approaches among targeted cellular therapies. Despite the potential benefit and durable responses observed in some patients receiving CAR-T therapies, serious and potentially fatal toxicities remain a major challenge. The most common CAR-T-associated toxicities include cytokine release syndrome (CRS), neurotoxicity, cytopenias, and infections. While CRS and neurotoxicity are generally managed with tocilizumab and corticosteroids, respectively, high-grade toxicities can be life-threatening. Close postinfusion monitoring and assessment of clinical laboratory parameters, patient-related and clinical risk factors (e.g., age, tumor burden, comorbidities, baseline laboratory parameters, and underlying abnormalities), and therapy-related risk factors (e.g., CAR-T type, dose, and CAR-T-induced toxicity) are effective strategies to mitigate the toxicities. Clinical laboratory parameters, including various cytokines, have been identified for CRS (interleukin [IL]-1, IL-2, IL-5, IL-6, IL-8, IL-10, C-reactive protein [CRP], interferon [IFN]-γ, ferritin, granulocyte-macrophage colony-stimulating factor [GM-CSF], and monocyte chemoattractant protein-1), neurotoxicity (IL-1, IL-2, IL-6, IL-15, tumor necrosis factor [TNF]-α, GM-CSF, and IFN-γ), cytopenias (IL-2, IL-4, IL-6, IL-10, IFN-γ, ferritin, and CRP), and infections (IL-8, IL-1β, CRP, IFN-γ, and procalcitonin). CAR-T-associated toxicities can be monitored and treated to mitigate the risk to patients. Assessment of alterations in clinical laboratory parameter values that are correlated with CAR-T-associated toxicities may predict development and/or severity of a given toxicity, which can improve patient management strategies and ultimately enable the patients to better tolerate these therapies.

Liver-FDG-uptake augments early PET/CT prognostic value for CD19-targeted CAR-T cell therapy in diffuse large B cell lymphoma

BACKGROUND

Despite revolutionary efficacy of CD19-CAR-T cell therapy (CAR-T) in aggressive B cell lymphoma, many patients still relapse mostly early. In early failure, distinct drugs support CAR-T which makes reliable and early prediction of imminent relapse/refractoriness critical. A complete metabolic remission (CR) on Fluor-18-Deoxyglucose (FDG) Positron-Emission-Computed Tomography (PET) 30 days after CAR-T (PET30) strongly predicts progression-free survival (PFS), but still fails in a relevant proportion of patients. We aimed to identify additional routine parameters in PET evaluation to enhance CAR-T response prediction.

RESULTS

Thirty patients with aggressive B cell lymphoma treated with CAR-T were retrospectively analyzed. Pre-CAR-T, LDH was the strongest PFS-predictor also by multivariate analysis. Post-CAR-T, 10 out of 14 patients (71.4%) with PET30-CR remained in disease remission, while 12 out of 16 patients (75%) with incomplete metabolic remission (PET30-nCR) relapsed after CAR-T. 28.6% of patients with PET30-CR ultimately progressed. Change of liver FDG-uptake from baseline to day30 (Delta-Liver-SUVmean) was identified as an independent biomarker for response. PET30-nCR and a decrease of Delta-Liver-SUVmean were associated with a high risk of tumor progression (HR 4.79 and 3.99, respectively). The combination of PET30 and Delta-Liver-SUVmean identified patients at very low, at intermediate and at very high risk of relapse (PFS not reached, 7.5 months, 1.5 months, respectively).

CONCLUSION

Additionally to PET30 metabolic remission, longitudinal metabolic changes in Delta-Liver-SUVmean predicted CAR-T efficiency. Our results may guide early intervention studies aiming to enhance CAR-T particularly in the very high-risk patients.

Development of ALL-Hematotox: predicting post-CAR T-cell hematotoxicity in B-cell acute lymphoblastic leukemia

Immune effector cell-associated hematotoxicity (ICAHT) is a major B-cell targeted chimeric antigen receptor (CAR) T-cell related toxicity. Although ICAHT incidence and severity is documented in large B-cell lymphoma (LBCL), mantle cell lymphoma (MCL), and multiple myeloma (MM), ICAHT has not been described in B-cell acute lymphoblastic leukemia (B-ALL). Similarly, the CAR-HEMATOTOX (CAR-HT) model, designed to predict severe prolonged neutropenia (≥14 days of absolute neutrophil count [ANC] <500/μL), has been validated in LBCL, MCL, and MM, but not in B-ALL. As B-ALL bone marrow (BM) infiltration can impact cytopenias, we sought to describe ICAHT and assess CAR-HT for predicting hematotoxicity in B-ALL. In a cohort of 156 children and young adults with relapsed/refractory B-ALL, the median duration of severe neutropenia (ANC <500/μL) was 13 days (95% confidence interval, 10-16 days), with 83 (53%) experiencing grade ≥3 ICAHT. Applying CAR-HT, nearly 90% were classified as high risk, demonstrating limited discriminative power and prompting further development. Using the association identified between BM disease burden and postinfusion neutropenia (r = 0.64, P < .0001), we developed the ALL-Hematotox (ALL-HT) score, which substitutes BM disease burden for ferritin in CAR-HT. The ALL-HT score associated with severe prolonged neutropenia (area under the curve = 0.84, P < .0001), and appropriately discriminated high-risk patients (47%) who had more cumulative days of neutropenia (26 vs 4 days; P < .0001), fewer rates of complete response (88% vs 98%; P = .03), and shorter median overall survival (9.8 vs 24 months; log-rank P = .0002). ALL-HT was also validated in 2 independent cohorts. The ALL-HT score refines a widely accepted predictive model of postinfusion hematotoxicity, which is applicable in B-ALL.

Addition of Phosphorous and IL6 to m-EASIX Score Improves Detection of ICANS and CRS, as Well as CRS Progression

Introduction: Cytokine release syndrome (CRS) and immune cell-associated neurotoxicity syndrome (ICANS) are both serious complications of CAR-T therapy associated with endothelial dysfunction, prompting prior use of a modified version of the endothelial activation and stress index (m-EASIX) to predict the occurrence of severe ICANS and CRS. Previous studies have linked both hypophosphatemia and elevated IL6 levels to CRS and ICANS. Our study aimed to enhance the early prediction of both syndromes by integrating phosphorous and IL-6 both together and separately into the m-EASIX score. Methods: Forty-two patients with non-Hodgkin's lymphoma presenting for CAR-T treatment were used to generate three variations in the m-EASIX score, assessing performance for the clinically actionable time points of day +0 through day +3. Results: The addition of phosphorous through the P-m-EASIX improved the predictive capabilities for the occurrence of ICANS, most notably on day +1 (AUC 89.6%; p = 0.0090, OR of 2.23; p = 0.0096) compared to the m-EASIX (AUC 80.8%; p = 0.0047, OR 1.72; p = 0.0046). The P-m-EASIX also showed enhanced predictive capabilities for the occurrence of CRS, with peak discriminatory function on day +3 (AUC 92.0%; p = <0.0001, OR 2.21; p = 0.0014). The addition of IL6 in the IL6-m-EASIX showed the highest discriminatory capacity for the prediction of CRS progression to grade ≥ 2 with peak function on day +3 (AUC 89.7%; p = 0.0040, OR 1.57; p = 0.031). Conclusions: Incorporating phosphorus levels into the m-EASIX score offered a cost-effective and straightforward method to improve the prediction of CAR-T toxicities. Larger-scale studies assessing the effectiveness of including phosphorus and IL-6 in the m-EASIX score to mitigate complications associated with CAR-T therapy are warranted.

Predictors and implications of renal injury after CD19 chimeric antigen receptor T-cell therapy

Chimeric antigen receptor (CAR) T cells targeting CD19 induce durable remissions in patients with relapsed or refractory non-Hodgkin lymphoma (NHL), but many patients experience treatment-related toxicity. Cytokine release syndrome and immune effector cell-associated neurologic syndrome are extensively characterized. However, limited data exist on the burden, predictors, and implications of acute kidney injury (AKI) after CAR T-cell therapy. On initial screening of the Food and Drug Administration adverse event reporting system, we identified a disproportionately high rate of renal adverse events among nearly 6,000 CAR T adverse event reports, suggesting it is clinically important in this patient population. In a subsequent single-center analysis of 399 NHL patients treated with CD19 CAR T cells, we found a substantial burden of AKI after CAR T infusion (10% and 5% of any grade and grade ≥2 AKI) with pre-renal causes being predominant (72%). Evolution to chronic kidney disease was rare, however, three patients required hemodialysis. Importantly, patients experiencing cytokine release syndrome and/or neurotoxicity as well as those with low serum albumin and high inflammatory cytokines, including IL-6 and TNF-α, were more likely to develop AKI. While pre-CAR T renal dysfunction was not associated with adverse outcomes, patients developing post-CAR T AKI had lower overall survival compared to their counterparts. Our findings indicate that renal dysfunction is a common toxicity of CAR T-cell therapy with meaningful prognostic impact. Notably, the link between systemic inflammation and renal dysfunction, suggests that readily available biomarkers may inform on renal injury risk after CAR T-cell therapy.

Novelties on Multiple Myeloma from the Main 2024 Hematology Conferences

Despite the introduction of several therapies in recent years, multiple myeloma (MM) remains a hematologic malignancy difficult to treat due to its extreme inter- and intra-patient heterogeneity. However, at the 2024 major international conferences, very significant data have emerged on new approaches that can improve outcomes even in high-risk or very advanced diseases. Up-front quadruplet combinations, including anti-CD38 monoclonal antibodies, proved to be the best therapy in terms of depth of response and long-term efficacy in both transplant-eligible and not-eligible patients with MRD assessment that could play a key role in determining the duration of therapy, avoiding unnecessary overtreatment. However, quadruplets also fail to overcome the negative prognostic value of high-risk cytogenetics or circulating tumour cells; therefore, in patients with these features, alternative approaches will have to be evaluated. Moreover, considering that not all patients, particularly older and frail ones, will be able to undergo such therapies, it will be necessary to refine the ability to identify the most appropriate therapy for each patient. Bispecific antibodies and CAR-T cells represent the new frontier in the treatment of advanced MM. However, they have shown even more efficacy with less toxicity in early relapses and functional high-risk patients. In the upfront setting, the results obtained with the inclusion of novel immunotherapies are extremely promising. In relapsed/refractory MM patients, agents such as belantamab mafodotin and CELMoDs, in combination with proteasome inhibitors or immunomodulatory agents, may represent another valid option.

Timeline and outcomes of viral and fungal infections after chimeric antigen receptor T-cell therapy: a large database analysis

OBJECTIVES

This large database analysis aims to describe the incidence, timeline, and risk factors for viral and fungal infections after chimeric antigen receptor (CAR) T-cell therapy.

METHODS

We queried a global research network database, TriNetX, for patients who received CAR T-cell therapy, who were identified and followed for the development of viral and fungal infections. Baseline demographic, oncologic history, laboratory data and medication histories were collected. We evaluated risk factors for respiratory viral infections (RVIs), herpesvirus, fungal infections and mortality using Cox regression.

RESULTS

A total of 2256 patients who received CAR T-cell therapy were included, 1867 (82.7%) were CD19-targeted and 400 (17.7%) were B-cell maturation antigen-targeted. After CAR T-cell infusion, RVIs were the most prevalent (23.3%) with a median onset of 160 days (interquartile range [IQR]: 52-348 days), whereas herpesvirus and fungal infections were less frequent, occurring in 13.6% and 11.4% of cases with median onsets of 71 (IQR, 18-252) and 73 days (IQR, 14-236 days), respectively. On multivariable Cox regression, independent predictors of RVI included acute lymphoblastic leukaemia (hazard ratio [HR], 1.61), prior haematopoietic cell transplant (HCT; HR, 1.29), cytokine release syndrome (HR, 1.41), hemophagocytic lymphohistiocytosis (HR, 1.96) and glucocorticoids (HR, 3.37). Prior HCT (HR, 2.00), hypogammaglobulinemia (HR, 1.51), immune effector cell-associated neurotoxicity syndrome (HR, 1.52) and hemophagocytic lymphohistiocytosis (HR, 1.99) were associated with a higher risk of herpesviruses. Independent predictors of fungal infections included prior HCT (HR, 1.59), cytokine release syndrome (HR, 1.58) and hypogammaglobulinemia (HR, 1.40). Idecabtagene vicleucel was associated with a lower risk of herpesvirus and fungal infections (HR, 0.39 and 0.44, respectively).

DISCUSSION

In a large cohort of CAR T-cell therapy recipients, RVIs were the most common but occurred later, whereas herpesvirus and fungal infections were less frequent but occurred earlier. Prospective studies investigating prophylaxis and pre-emptive monitoring strategies are needed in this population.

Tisagenlecleucel in Practice: Real-World Lessons in Pediatric and Young Adult B-ALL

The global multi-institutional registration trial (ELIANA) of CD19.41BB.zeta chimeric antigen receptor (CAR) T cell therapy forged the path to the first FDA-approved CAR T product, tisagenlecleucel. Since its approval, extensive post-market experience with CAR T cells in children and young adults has amassed, allowing several multi-institutional efforts to leverage real-world data. Real-world data has validated clinical trial findings and provided insights into CAR T-cell use in patient groups not included in early clinical trials, such as children <3 years, patients with active CNS and isolated extramedullary disease, and patients treated in first relapse. Data from multi-centered consortia has also identified cohorts who experienced inferior outcomes post-tisagenlecleucel, informing high-risk groups for whom further treatment optimization is needed, and delineating treatment variables, such as CAR T cell dose and lymphodepleting chemotherapy pharmacokinetics, that impact outcomes. In this early stage of CAR T-cell therapies, real-world experience provides an increasingly rich data reservoir and an invaluable resource to investigate and address clinical gaps for CAR T recipients. This review highlights key insights gained from post-market studies that have informed clinical use of CAR T-cell therapy for children and young adults with B-ALL.

Development and validation of predictive models of early immune effector cell-associated hematotoxicity

ABSTRACT

Immune effector cell-associated hematotoxicity (ICAHT) is associated with morbidity and mortality after chimeric antigen receptor (CAR) T-cell therapy. To date, the factors associated with ICAHT are poorly characterized, and there is no validated predictive model of ICAHT as defined by current consensus criteria. Therefore, we performed comprehensive univariate analyses to identify factors associated with severe (grade 3-4) early ICAHT (eICAHT) in 691 patients who received commercial or investigational CAR T-cell therapy for hematologic malignancies. In univariate logistic regression, preinfusion factors associated with severe eICAHT included disease type (acute lymphoblastic leukemia), prelymphodepletion (pre-LD) blood counts including absolute neutrophil count (ANC), lactate dehydrogenase (LDH), and inflammatory (C-reactive protein [CRP], ferritin, and interleukin-6 [IL-6]) and coagulopathy biomarkers (D-dimer). Postinfusion laboratory markers associated with severe eICAHT included early and peak levels of inflammatory biomarkers (CRP, ferritin, and IL-6), coagulopathy biomarkers (D-dimer), peak cytokine release syndrome grade, and peak neurotoxicity grade. We trained (n = 483) and validated (n = 208) 2 eICAHT prediction models (eIPMs): eIPMPre including preinfusion factors only (disease type and pre-LD ANC, platelet count, LDH, and ferritin) and eIPMPost containing both preinfusion (disease type and pre-LD ANC, platelet count, and LDH) and early postinfusion (day +3 ferritin) factors. Both models generated calibrated predictions and high discrimination (area under the receiver operating characteristic curve in test set, 0.87 for eIPMPre and 0.88 for eIPMPost), with higher net benefit in decision curve analysis for eIPMPost. Individualized predictions of severe eICAHT can be generated from both eIPMs using our online tool (available at https://eipm.fredhutch.org).

Invasive Fungal Disease After Chimeric Antigen Receptor-T Immunotherapy in Adult and Pediatric Patients

Invasive fungal diseases (IFDs) have been documented among the causes of post-chimeric antigen receptor-T (CAR-T) cell immunotherapy complications, with the incidence of IFDs in CAR-T cell therapy recipients being measured between 0% and 10%, globally. IFDs are notorious for their potentially life-threatening nature and challenging diagnosis and treatment. In this review, we searched the recent literature aiming to examine the risk factors and epidemiology of IFDs post-CAR-T infusion. Moreover, the role of antifungal prophylaxis is investigated. CAR-T cell therapy recipients are especially vulnerable to IFDs due to several risk factors that contribute to the patient's immunosuppression. Those include the underlying hematological malignancies, the lymphodepleting chemotherapy administered before the treatment, existing leukopenia and hypogammaglobinemia, and the use of high-dose corticosteroids and interleukin-6 blockers as countermeasures for immune effector cell-associated neurotoxicity syndrome and cytokine release syndrome, respectively. IFDs mostly occur within the first 60 days following the infusion of the T cells, but cases even a year after the infusion have been described. Aspergillus spp., Candida spp., and Pneumocystis jirovecii are the main cause of these infections following CAR-T cell therapy. More real-world data regarding the epidemiology of IFDs and the role of antifungal prophylaxis in this population are essential.

Successful generation of fully human, second generation, anti-CD19 CAR T cells for clinical use in patients with diverse autoimmune disorders

BACKGROUND

B-cell targeting chimeric antigen receptor (CAR) T-cell therapies, which lead to profound B-cell depletion, have been well-established in hematology-oncology. This deep B-cell depletion mechanism has prompted the exploration of their use in B-cell driven autoimmune diseases. We herein report on the manufacturing of KYV-101, a fully human anti-CD19 CAR T-cell therapy, derived from patients who were treated across a spectrum of autoimmune diseases.

METHODS

KYV-101 was manufactured from peripheral blood-derived mononuclear cells of 20 patients across seven autoimmune disease types (neurological autoimmune diseases, n = 13; rheumatological autoimmune diseases, n = 7). Patients ranged from 18 to 75 years of age. Duration of disease ranged from <1 to 23 years since diagnosis. Patients were heavily pretreated, and most were refractory to prior immunosuppressive treatments. Apheresis was collected across nine sites, cryopreserved, and shipped to the manufacturing facility. Healthy donor apheresis samples were collected for manufacturing comparison. Manufacturing was performed using the CliniMACS Prodigy system. Cells were enriched for CD4+/CD8+ T cells, transduced with a third generation lentiviral vector encoding the CAR, expanded in vitro, and harvested. Percent cell viability, T-cell purity, cellular expansion, and transduction efficiency were assessed. Activity was assessed using cytokine release assays for KYV-101 CAR T cells co-cultured with different CD19+/- target cell lines.

RESULTS

KYV-101 was successfully manufactured for 100% of patients. Transduced cell populations were highly viable, with expansion ranging from 11 to 66 fold at Day 8, and were comparable across disease types. Healthy donor-derived controls displayed similar expansion ranges. High CAR expression and transduction rates were observed, ranging between 37 and 77% with low variation in transgene copy number (two to four per cell). Cell viability of the final KYV-101 drug product ranged from 87 to 97%. KYV-101 displayed robust CD19-dependent and effector dose-related release of the pro-inflammatory cytokine IFN-γ.

CONCLUSIONS

KYV-101 manufacturing yielded a CAR T-cell product with high viability and consistent composition and functionality, regardless of disease indication, pre-treatment, and heterogeneity of the incoming material. Cryopreservation of the apheresis and final drug product enabled widespread distribution. These results support the robustness of the manufacturing process for the fully human KYV-101 anti-CD19 CAR T-cell therapy drug product for patients across diverse autoimmune disease types.

Brexucabtagene autoleucel in-vivo expansion and BTKi refractoriness have a negative influence on progression-free survival in mantle cell lymphoma: Results from CART-SIE study

Brexucabtagene autoleucel (brexu-cel) has revolutionized the treatment of patients affected by mantle cell lymphomas. In this prospective, observational multicentre study, we evaluated 106 patients, with longitudinal brexu-cel kinetics in peripheral blood monitored in 61 of them. Clinical outcomes and toxicities are consistent with previous real-world evidence studies. Notably, beyond established poor prognostic factors-such as blastoid variant and elevated lactate dehydrogenase-Bruton tyrosine-kinase inhibitors (BTKi) refractoriness and platelet count emerged as significant predictors of survival. Specifically, the 1-year overall survival was 56% in BTKi-refractory patients compared to 92% in BTKi-relapsed patients (p = 0.0001). Our study also demonstrated that in-vivo monitoring of brexu-cel expansion is feasible and correlates with progression-free survival and toxicities. Progression-free survival at 1 year was 74% in patients categorized as strong expanders, based on brexu-cel peak concentration, versus 54% in poor expanders (p = 0.02). Furthermore, in-vivo expansion helped identify a high-risk group of non-responders, those with progressive or stable disease at the 90-day post-infusion evaluation (OR = 4.7, 95% CI = 1.1-34, p = 0.04) characterized by dismal outcomes. When integrated with other clinical factors, monitoring brexu-cel expansion could assist in recognizing patients at high risk of early relapse.

Basic Concepts and Indications of CAR T Cells

Chimeric antigen receptor (CAR) T cell therapy has revolutionized cancer immunotherapy, particularly for hematological malignancies. This personalized approach is based on genetically engineering T cells derived from the patient to target antigens expressed-among others-on malignant cells. Nowadays they offer new hope where conventional therapies, such as chemotherapy and radiation, have often failed. Since the first FDA approval in 2017, CAR T cell therapy has rapidly expanded, proving highly effective against previously refractory diseases with otherwise a dismal outcome. Despite its promise, CAR T cell therapy continues to face significant challenges, including complex manufacturing, the management of toxicities, resistance mechanisms that impact long-term efficacy, and limited access as well as high costs, which continue to shape ongoing research and clinical applications. This review aims to provide an overview of CAR T cell therapy, including its fundamental concepts, clinical applications, current challenges, and future directions in hematological malignancies.

Concentration-dependent effects of immunomodulatory cocktails on the generation of leukemia-derived dendritic cells, DCleu mediated T-cell activation and on-target/off-tumor toxicity

Acute myeloid leukemia (AML) remains a devastating diagnosis in clear need of therapeutic advances. Both targeted dendritic cells (DC) and particularly leukemia-derived dendritic cells (DCleu) can exert potent anti-leukemic activity. By converting AML blasts into immune activating and leukemia-antigen presenting cells, DC/DCleu-generating protocols can induce immune responses against AML blasts. Such protocols combine approved response modifiers (i.e., GM-CSF and PGE1/OK-432/PGE2) that synergistically improve the conversion of AML blasts into (mature) DC/DCleu. To guide potential clinical application of these response modifiers, we analyzed three different DC-generating protocols that combine a constant GM-CSF dose with varying concentrations of PGE1 (Kit-M), OK-432 (Kit-I), and PGE2 (Kit-K). Here, we specifically aimed to assess how different response modifier concentrations impact DC/DCleu generation, immune cell activation and leukemic blast lysis. We found that all immunomodulatory kits were effective in generating mature and leukemia-derived DCs from healthy and leukemic whole blood. For Kit-M, we noted optimal generation of DC-subsets at intermediary concentration ranges of PGE1 (0.25-4.0 µg/mL), which facilitated upregulation of activated and memory T-cells upon mixed lymphocyte culture, and efficient anti-leukemic activity in cytotoxicity assays. For Kit-I, we observed DC/DCleu generation and enhanced T- and immune cell activation across a broader range of OK-432 concentrations (5-40 µg/mL), which also facilitated improved leukemic blast killing. In conclusion, our results highlight that Kit-mediated DC/DCleu generation, immune cell activation and blast lysis are dependent on the concentration of response modifiers, which will guide future clinical development. Overall, DCleu-based immunotherapy represents a promising treatment strategy for AML patients.

CD19-directed chimeric antigen receptor T-cell therapy: what can we learn from the haematologist?

CD19-directed chimeric antigen receptor (CAR) T-cell therapy, originally developed for haematological malignancies, has recently emerged as a promising therapy for patients with autoimmune diseases. By selectively depleting CD19-positive B-cells, this therapy brings a new approach in resetting immune dysregulation and potentially providing long-term remission for patients with a refractory disease. Recent reports have highlighted its effectiveness in conditions such as SLE, systemic sclerosis and myositis. However, while these early results are encouraging, questions remain regarding strategies for optimal patient selection and minimising toxicity on the short and long term. The experiences with CD19 CAR T-cell therapy in haematology may offer valuable insights for immunologists and rheumatologists. This article reviews the key principles learnt in haematology, the results and the mechanisms behind its efficacy, toxicities, and the challenges that need to be addressed for its broader application in clinical practice.

How I treat older patients with relapsed/refractory diffuse large B-cell lymphoma

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is an aggressive, yet curable, malignancy, but older patients are at higher risk of relapsed disease because they may not be eligible for full-intensity frontline chemoimmunotherapy or have comorbidities that limit standard treatments. Recent years have brought more treatment options than ever for this patient population, but it remains challenging to determine which can be safely and effectively offered to older patients. Formal determinations of fitness including geriatric assessments remain critical, but there is less guidance on how to best use this tool in the relapsed setting. Chimeric antigen receptor T-cell therapy is accessible to older patients, provided they can be supported through the intensive road to this treatment. If relapse occurs despite this or alternative therapies are preferred, many novel therapeutic options and combinations exist with some potential modifications for older adults, such as bispecific antibodies, tafasitamab and lenalidomide, polatuzumab-containing regimens, or loncastuximab tesirine. This article provides a summary of our approach to the management of this diverse population of older patients with relapsed or refractory DLBCL.

Adoptive cell therapies in thoracic malignancies: a comprehensive review

This review aims to summarize recent studies and findings within adoptive cell therapies, including tumor-infiltrating lymphocytes, genetically engineered T cell receptors, and chimeric antigen receptor T cells, in the treatment of thoracic malignancies, including non-small cell lung cancer, small cell lung cancer, and malignant pleural mesothelioma. Several trials are ongoing, and a few have reported results, suggesting that adoptive cell therapies may represent a potential treatment option for these patients, especially when checkpoint inhibition has failed. We also discuss the potential implementation of these therapies, as they present a new toxicity profile and an intrinsic financial burden. Despite the challenges to overcome, such as the accurate identification of antigens and developing strategies to improve efficacy and toxicity profiles, new cellular therapies are experiencing significant development in the field of thoracic malignancies.

[Prerequisite and organisation of health-care pathways for Cell and Gene therapies, using Mesenchymal Stromal Cells (MSC) or Chimeric Antigen Receptor (CAR) T cells, in patients with autoimmune systemic diseases]

First-line treatments of autoimmune systemic diseases (ARD) are based on the use of various types of immunosuppressive or immunomodulatory drugs, either alone or in association, according to standardized reference protocols. Prolonged use of these drugs in severe or refractory ARD is associated with high morbidity and increased mortality. Innovative cell therapies represent a new promising approach for patients with ARDs, with the recent clinical use of: a) mesenchymal stromal cells (MSCs), based on their immunomodulatory, antifibrotic and pro-angiogenic properties and b) Chimeric Antigen Receptors (CAR) T cell therapies T lymphocytes, where genetically modified expression of a chimeric antigen receptor (CAR-T cells). Therapeutic use of MSC or CAR-T cells, remains indications of exception in patients with severe ARDs resistant to prior standard therapies with new prerequisite and organisation of health-care pathways as compared to traditional drugs, not only for the Cell and Gene Therapy (CGT) product definition and delivery process, but also for the patient clinical management before and after administration of the CGT product. The aim of this workshop under the auspices of the French Speaking Society of Bone Marrow and Cell transplantation (SFGM-TC) working group on autoimmune diseases (MATHEC) is to describe: a) the prerequisite for French hospitals to set-up the specific health-care pathways for MSC or CART therapy in ARDs patients, in accordance with regulatory and safety needs to perform academic or industry sponsored clinical trials, and b) the care-pathway for ARD patients treated with CGT, highlighting the importance of working in tandem between the ARD and the CAR-T cell specialist all along the indication, procedures and follow-up of ARDs. Patient safety considerations are central to guidance on patient selection to be validated collectively at the multidisciplinary team meeting (MDTM) based on recent (less than 3 months) thorough patient evaluation. MSC and CAR-T procedural aspects and follow-up are then carried out within appropriately experienced and SFGM-TC accredited centres in close collaboration with the ADs specialist.

[Hematological toxicities post-CAR-T cells: Recommendations of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Chimeric antigen receptor T cell (CAR-T cell) therapy has become a standard-of-care for several hematological and a promising treatment for solid malignancies or for selected non-malignant autoimmune disorders. Hematological complications following this treatment are very common with the majority of patients experiencing at least one cytopenia after CAR-T cell injections. The management of these adverse events is not standardized and represents an area of active research and unmet clinical needs. This harmonization workshop, gathering a group of experts who analyzed this topic, has been conceived for the optimization of the management of patients presenting with post-CAR-T cell hematological toxicities. Based on the data present in the literature, these practical recommendations were made to harmonize the practices of Francophone centers involved in the management of these patients.

Prognostic significance of immune reconstitution following CD19 CAR T-cell therapy for relapsed/refractory B-cell lymphoma

Immune deficits after CD19 chimeric antigen receptor (CAR) T-cell therapy can be long-lasting, predisposing patients to infections and non-relapse mortality. In B-cell non-Hodgkin lymphoma (B-NHL), the prognostic impact of immune reconstitution (IR) remains ill-defined, and detailed cross-product comparisons have not been performed to date. In this retrospective observational study, we longitudinally characterized lymphocyte subsets and immunoglobulin levels in 105 B-NHL patients to assess patterns of immune recovery arising after CD19 CAR-T. Three key IR criteria were defined as CD4+ T helper (TH) cells > 200/µL, any detectable B cells, and serum immunoglobulin G (IgG) levels >4 g/L. After a median follow-up of 24.6 months, 38% of patients displayed TH cells, 11% showed any B cells, and 41% had IgG recovery. Notable product-specific differences emerged, including deeper TH cell aplasia with CD28z- versus longer B-cell aplasia with 41BBz-based products. Patients with any IR recovery experienced extended progression-free survival (PFS) (median 20.8 vs. 1.7 months, p < 0.0001) and overall survival (OS) (34.9 vs. 4.0 months, p < 0.0001). While landmark analysis at 90 days confirmed improved PFS in patients with any recovery (34.9 vs. 8.6 months, p = 0.005), no significant OS difference was noted. Notably, 72% of patients with refractory disease never displayed recovery of any IR criteria. Early progressors showed diminished IR at the time of progression/relapse compared to patients with late progression/recurrence (after Day 90). Our results highlight the profound immune deficits observed after CD19 CAR-T and shed light on the intersection of IR and efficacy in B-NHL. Importantly, IR was impaired considerably postprogression, carrying significant implications for subsequent T-cell-engaging therapies and treatment sequencing.

Late-onset relapsing neurotoxicity after Brexucabtagene autoleucel associated with high chimeric antigen receptor T cells in cerebrospinal fluid

BACKGROUND AIMS

Mounting evidence suggests that persistent cell expansion is the main driver for both efficacy and toxicity of chimeric antigen receptor (CAR) T-cell therapy. Hereby, we describe a case of delayed recurrent neurotoxicity associated with late CAR T-cells re-expansion.

CASE DESCRIPTION

A 44-year-old man suffering from mantle cell lymphoma received brexu-cel. After infusion, he developed grade 2 cytokine release syndrome. On day +11, grade 3 neurotoxicity was reported and high-dose methylprednisolone was started with a complete resolution of neurological manifestations. On day +30, he experienced a late-onset CAR T-cell toxicity associated with CAR T-cell re-expansion. The patient was treated with tocilizumab and dexamethasone, with resolution of symptoms. On day +58, he was readmitted for new onset of neurotoxicity. Notably, a new CAR T-cell expansion was observed, with an unexpectedly elevated cerebrospinal fluid/blood ratio. The patient was promptly treated with dexamethasone and then escalated to high-dose methylprednisolone and anakinra, with resolution of his neurologic condition noted.

CONCLUSIONS

CAR T-cell-related neurotoxicity usually has an early monophasic course. To our knowledge, this is the first case of late-onset, recurrent neurotoxicity. Moreover, an elevated level of cerebrospinal fluid CAR T cells was observed, which may suggest that the delayed neurotoxicity was primarily caused by the brain infiltration of CAR T cells rather than driven by cytokine-mediated neuroinflammation.

Secondary haematological dysplasia after CAR-T-cell therapy for acute lymphoblastic leukaemia in children

The use of CAR-T is becoming more widespread in the treatment of haematological malignancies. In adults, secondary myelodysplastic syndromes (MDS) after CAR-T have been described. However, there are currently no data on the risk of MDS following CAR-T in children treated for acute lymphoblastic leukaemia (ALL). We studied all children treated with CAR-T cells at Hospital Sant Joan de Déu in Barcelona and those with persistent cytopenias were evaluated at the cytological, cytogenetic, and molecular levels to look for MDS. A total of 106 patients received CAR-T for ALL. Among 40 patients without early relapse or subsequent therapy after CAR-T, four fulfilled the WHO criteria for myelodysplasia. These four patients had received a haematopoietic stem cell transplantation (HSCT) prior to CAR-T and presented cytopenias with severe dysplastic changes in bone marrow after CAR-T. One patient had clonal MDS with high-risk cytogenetics arising from the host cells requiring a HSCT. Three patients had non-progressive dysplasia arising from the donor cells. Two are alive in complete remission with stable cytopenias and one succumbed to ALL relapse. This is the first description of post-CAR-T MDS and haematological dysplasia in children and highlights the need to monitor children with persistent post-CAR-T cytopenias.

Severe cytopenia after chimeric antigen receptor-T cell driven by large granular lymphocytes and responsive to steroids

Immune effector cell-associated hematotoxicity (ICAHT) is a common toxicity associated with an important morbidity after chimeric antigen receptor (CAR)-T-cell therapy. Multiple factors seem to be involved in the development of severe ICAHT, making its management difficult. Here, we report three cases of severe ICAHT after axicabtagene-ciloleucel (axi-cel) for diffuse large B-cell lymphoma showing an expansion of large granular lymphocyte in the bone marrow with a CD3/CD57-positive non-CAR-T immunophenotype. We show that it is possible to treat them with low-dose steroids, obtaining a striking resolution of cytopenias with no deleterious impact on the underlying malignancy.

Real-World Characterization of Toxicities and Medication Management in Recipients of CAR T-Cell Therapy for Relapsed or Refractory Large B-Cell Lymphoma in Nova Scotia, Canada

Nova Scotia (NS) began offering CAR T-cell therapy as a third-line standard of care for eligible patients with relapsed or refractory large B-cell lymphoma (r/r LBCL) in 2022. Recipients of CAR T-cell therapy often experience acute toxicities, including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), which require close monitoring and prompt management. This retrospective review aimed to describe the characteristics of adult patients with r/r LBCL deemed eligible to receive CAR T-cell therapy with axicabtagene ciloleucel in NS between January 2022 and June 2024, the toxicities experienced and toxicity management, hospital visits and intensive care unit (ICU) admissions, the utilization of toxicity management guidelines, and general efficacy outcomes. Twenty-seven patients received axicabtagene ciloleucel. All patients experienced CRS (7.4% grade ≥ 3), and 55.6% developed ICANS (25.9% grade ≥ 3). The median hospital stay was 18 days, with 40.7% requiring ICU admission. There was one treatment-related mortality. Most CRS (85.2%) and ICANS (80.0%) cases were managed according to the guidelines. By day +100, the best objective response rate was 81.5% (44.4% complete responses). Patients who received CAR T-cell therapy in NS, Canada, experienced comparable toxicities and efficacy to those reported in pivotal clinical trials and other real-world experiences.

Evolving strategies for addressing CAR T-cell toxicities

The field of chimeric antigen receptor (CAR) T-cell therapy has grown from a fully experimental concept to now boasting a multitude of treatments including six FDA-approved products targeting various hematologic malignancies. Yet, along with their efficacy, these therapies come with side effects requiring timely and thoughtful interventions. In this review, we discuss the most common toxicities associated with CAR T-cells to date, highlighting risk factors, prognostication, implications for critical care management, patient experience optimization, and ongoing work in the field of toxicity mitigation. Understanding the current state of the field and standards of practice is critical in order to improve and manage potential toxicities of both current and novel CAR T-cell therapies as they are applied in the clinic.

Supportive care in myeloma-when treating the clone alone is not enough

The overall survival in patients with multiple myeloma has increased over recent decades. This trend is anticipated to further advance with the emergence of T-cell-redirecting therapies, including chimeric antigen receptor T-cell (CAR T) therapy and T-cell-engaging bispecific antibodies. Despite these therapeutic improvements, treatment-related adverse events impede quality of life. This underscores the imperative of optimizing supportive care strategies to maximize treatment outcomes. Such optimization is crucial not only for patient well-being but also for treatment adherence, which may translate into long-term disease control. We here describe a) how to prevent bone disease, b) a risk-adapted thrombosis prophylaxis approach, c) the management of on-target, off-tumor toxicity of G-protein-coupled receptor class C group 5 member D-targeting T-cell-redirecting therapies, and d) infectious prophylaxis, with a focus on infections during T-cell-redirecting therapies.

CARs for lymphoma

Chimeric Antigen Receptor (CAR)-T cell therapy has revolutionized treatment options for B-cell Non-Hodgkin Lymphoma (NHL). CD19-targeting CAR-T cell therapy is approved for treatment in Diffuse Large B Cell Lymphoma, Follicular Lymphoma, Mantle Cell Lymphoma, and Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma. CAR-T cells demonstrate robust and durable responses even in heavily pretreated patients. Clinicians should monitor for Cytokine Release Syndrome (CRS) and Immune Effector Cell Neurotoxicity Syndrome (ICANS), as well as cytopenias, infection, and secondary malignancies. Ongoing questions remain in improving manufacturing efficacy, sequencing CAR-T cells amongst other therapies including bi-specific antibodies (BiTEs), and predicting optimal responders. In addition, novel CARs are being developed with alternative targets or that secrete activating cytokines (i.e. "armored CARs"). CAR-T cells represent an effective lymphoma therapy and should be considered for eligible patients.

Infections following chimeric antigen receptor T cell therapy: 2018-2022

BACKGROUND

Chimeric antigen receptor (CAR) T-cell therapy is an emerging therapeutic modality for relapsed and refractory hematological malignancies. Infectious complications following CAR T-cell therapy are not well defined.

METHODS

This is a retrospective analysis of data on patients who received CAR T-cell therapy between April 2018 and December 2022 at the Karmanos Cancer Center, Detroit. Patients' data were collected up to their last known clinic or inpatient follow-up visit. An infectious episode was defined as any microbiologically proven or clinically documented infection.

RESULTS

Seventy-six patients received therapy with FDA-approved CAR T-cell products. Thirty-three patients (43.4%) had at least one infectious episode. There were 61 infectious episodes during a median follow-up of 184 (96-340) days. Median duration for the onset of infection was 59 (22-209) days. Bacterial and viral infections occurred in 42.6% and 41% of the infectious episodes, respectively. COVID-19 was the most common infectious complication (14.8%). Time-to-event analysis showed that most infections occurred within the first 100 days. Empirical antibiotic use during Cytokine Release Syndrome/Immune effector Cell-Associated Neurotoxicity Syndrome (CRS/ICANS) in the absence of documented bacterial infection was reported in 85.7% of patients. Clostridioides difficile accounted for 11.5% of all infectious episodes. Five of six patients with C. difficile infection had CRS/ICANS and received antibiotics.

CONCLUSION

COVID-19 and C. difficile infection were the most common infections following CAR T-cell therapy. Most infections occurred within the first 100 days. Empiric antibiotic use and C. difficile infection were common in patients with CRS/ICANS, in the absence of documented bacterial infection, thus providing an excellent opportunity for antimicrobial stewardship in this population.

Chimeric Antigen Receptor (CAR) T-cell Therapy in the Treatment of Diffuse Large B-cell Lymphoma (DLBCL): A Systematic Review

Chimeric antigen receptor (CAR) T-cell therapy has shown very promising results in the treatment of refractory or relapsed diffuse large B-cell lymphoma (DLBCL). This systematic review evaluates the effectiveness and side effects of CAR T-cell therapies, focusing on factors affecting both clinical outcomes and adverse effects. This review included data from 14 studies involving 1392 patients with DLBCL who underwent CAR T-cell therapy. These studies include both randomized clinical trials and observational studies, which would help to analyze the effectiveness and safety profiles. The review highlights that CAR T-cell therapies, mainly tisagenlecleucel (Tisa-cel) and axicabtagene ciloleucel (Axi-cel), have shown superior effectiveness in comparison to standard chemotherapy in patients with relapsed or refractory DLBCL. Lisocabtagene maraleucel (Liso-cel) showed significant improvement outcomes in event-free and progression-free survival. However, CAR T-cell therapies are associated with many side effects. The most common side effects include hematologic toxicity, prolonged neutropenia, and infections, while clinical outcomes are highly impacted by many factors, which include a pro-inflammatory state, PPM1D gene mutation, infusion timing, and circulating monocytes.