Search

Two CD19 chimeric antigen receptor (CAR) T cell therapies are now approved by the US Food and Drug Administration for the treatment of relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) and histological variants: axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) (Neelapu I et al i , [6]; Schuster I et al i , [9]). Clinically, it remains unclear as to when the HLH features of CRS are significant enough to consider treatment with therapies used for non-CAR T-associated HLH, such as etoposide or methotrexate (Neelapu I et al i , [8]). Our case series suggests that the timing of onset of CAR T-associated HLH may differ between patients, with concern when delayed or recurrent HLH symptoms occur with a rising ferritin level, which is when HLH-directed therapies should be considered. [Extracted from the article]

CAR T cells have been extensively investigated using constructs targeting CD19+ B cells for lymphoid malignancies demonstrating efficacy (Neelapu NEJM 2018; Schuster NEJM 2018). One of the main challenges of adoptive T cell therapy are immune mediated toxicities of cytokine release syndrome (CRS) and neurotoxicity (NT). Despite impressive objective response rates, durable responses are only seen in approximately 40% of patients treated in the pivotal axicabtagene ciloleucel (axi-cel) and tisagenlecleucel trials, highlighting the need for better understanding of the mechanisms of toxicity and efficacy. We aimed to evaluate the association of early biomarkers with severe toxicity and day 90 outcomes in patients treated with commercial axi-cel in a real world setting. Seventy-five patients treated with commercial axi-cel were included in this analysis. Baseline characteristics are summarized in Table 1. Patient serum samples were collected at baseline (within 30 days of conditioning chemotherapy), and then daily thereafter starting at the day of axi-cel infusion. Serum cytokine samples were analyzed using the Ella multiplex assay system. Cytokines analyzed include IL1b, IL2, IL6, IL15, TNFa, IFNg, Angiopoietin 1 and 2, as well as CRP and ferritin. Toxicities were graded daily using ASTCT consensus guidelines and retrospectively confirmed. Outcomes were evaluated at day 90 by the treating physician according to the International Working Group Response Criteria for Malignant lymphoma. P values were calculated using Wilcoxon rank sum test. We observed that baseline levels of CRP (p=0.0018) and Angiopoietin 2/1 ratio (p=0.0092) were associated with grade ≥3 [n=16] neurotoxicity Figure 1A-B). Baseline elevated levels of CRP (p=0.0413) and Ferritin (0.0264) were associated with more grade ≥3 CRS [n=16] (Figure 1C-D). Baseline elevated levels of CRP(p=0.0016), ferritin(p=0.0096) and IL6 (p=0.0029) were associated with poor outcomes at D90 defined as stable disease, progressive disease or death (Figure 1E-G). We demonstrate that baseline biomarker profile can identify patients at highest risk of developing severe toxicity and/or and treatment resistance highlighting the need to validate these findings in prospective studies. Patients in this poor outcome cohort may benefit from clinical trials evaluating prophylactic agents or more combination therapies to ameliorate severe toxicities or increase response rates. [ABSTRACT FROM AUTHOR]

Introduction One of the main complications of adoptive T cell therapy (ACT) is the en-masse activation of tumor-reactive T cells leading to adverse events. These are classified as cytokine release syndrome (CRS) and CAR T Related Encephalopathy Syndrome (CRES). Here, we report the results of cytokine analysis using a point of care (POC) device to predict immune-related toxicities in patients with relapsed/refractory (R/R) DLBCL treated with axicabtagene ciloleucel (axi-cel). Methods Patients with R/R DLBCL treated with commercial axi-cel were included in this study. To select which cytokines to monitor, we retrospectively analyzed 38 serum cytokines in a cohort of 53 patients with R/R B-ALL who were treated with 19-28z CAR T cells. We observed several cytokines which were significantly elevated in patients with CRS and/or CRES requiring treatment (Figure 1a). Based on this analysis and results of published studies, eight serum proteins were selected, including IL-1b, IL-2, IL-6, IL-15, IFNg, TNFa, and angiopoietin-1 &2 (ANG1/ANG2). We monitored these proteins using a POC device that allows for rapid daily monitoring with a turnaround time of two hours. CRS and CRES were prospectively graded using revised Lee criteria and the CARTOX group respectively. Results A total of 20 patients with R/R DLBCL treated with commercial axi-cel were identified. Median age 64 years (range 43-73). Grades 1-3 CRS were observed in 45%, 40% and 5% of patients respectively. There were no observed grade 0 or grade 4 CRS. There were two patients (10%) who died in the setting of severe toxicity. Patients with grade 5 CRS had higher levels of IL-6 and angiopoietin 2/angiopoietin 1 ratio at day one, which correlated with severity of toxicity r=0.52 (p= 0.039) and r=0.53 (p=0.033) respectively (Fig. 1b). Patients with high grades CRS had elevated levels of IL-15 at day seven (r=0.83, p=0.006). The majority of patients (55%) had grades 1-2 CRES. There were no significant correlations between serum cytokine levels and CRES. Conclusion In this analysis of 20 patients, we observed a correlation between severe CRS and elevated serum cytokine levels of IL-6 and ANG2/ANG1 ratio at day one suggesting that these biomarkers may be utilized to predict severe toxicity in patients treated with ACT. While this study is limited by small sample size, our observations correlate with previously published biomarkers data in patients enrolled in clinical trials. In select cases, monitoring of cytokines using the POC device provided clinical insight that wasn't evident from standard biomarkers. For example, one patient who developed delayed CRS had high serum levels of IL-6 but did not have elevated levels of CRP (Fig.1c). We continue to enroll patients to validate cytokines as predictive biomarkers with the goal of informing the development of preventative strategies to mitigate CAR T cell therapy immune related adverse events. [ABSTRACT FROM AUTHOR]