Baseline Serum Inflammatory Proteins Predict Poor CAR T Outcomes in Diffuse Large B-cell Lymphoma.

A subset of patients with diffuse large B-cell lymphoma (DLBCL) treated with CD19 chimeric antigen receptor (CAR) T-cell therapy have poor clinical outcomes. We report serum proteins associated with severe immune-mediated toxicities and inferior clinical responses in 146 patients with DLBCL treated with axicabtagene ciloleucel. We develop a simple stratification based on pre-lymphodepletion C reactive protein (CRP) and ferritin to classify patients into low-, intermediate-, and high-risk groups. We observe that patients in the high-risk category were more likely to develop grade ≥3 toxicities and had inferior overall and progression-free survival. We sought to validate our findings with two independent international cohorts demonstrating that patients classified as low-risk have excellent efficacy and safety outcomes. Based on routine and readily available laboratory tests that can be obtained prior to lymphodepleting chemotherapy, this simple risk stratification can inform patient selection for CAR T-cell therapy. SIGNIFICANCE: CAR T-cell therapy has changed the treatment paradigm for patients with relapsed/refractory hematologic malignancies. Despite encouraging efficacy, a subset of patients have poor clinical outcomes. We show that a simple clinically applicable model using pre-lymphodepletion CRP and ferritin can identify patients at high risk of poor outcomes. This article is featured in Selected Articles from This Issue, p. 80.

Toxicities associated with adoptive cellular therapies.

Chimeric antigen receptor (CAR) T cell therapy is an effective strategy for the treatment of relapsed/refractory hematologic malignancies leading to the Food and Drug Administration (FDA) approval of five CAR T cell products. Despite encouraging efficacy, the widespread utilization of CAR T cell therapy is limited by unique immune mediated toxicities, primarily cytokine release syndrome (CRS) and neurologic toxicity. Data regarding late effects and long-term toxicities of CAR T cell therapy is evolving and includes prolonged cytopenias, hypogammaglobulinemia, infections and secondary malignancies. In this review, we will describe the clinical presentation, diagnosis, mechanisms and management of short- and long-term toxicities of CAR T cell therapy.

Tumor Microenvironment Composition and Severe Cytokine Release Syndrome (CRS) Influence Toxicity in Patients with Large B-Cell Lymphoma Treated with Axicabtagene Ciloleucel.

PURPOSE: One of the challenges of adoptive T-cell therapy is the development of immune-mediated toxicities including cytokine release syndrome (CRS) and neurotoxicity (NT). We aimed to identify factors that place patients at high risk of severe toxicity or treatment-related death in a cohort of 75 patients with large B-cell lymphoma treated with a standard of care CD19 targeted CAR T-cell product (axicabtagene ciloleucel). EXPERIMENTAL DESIGN: Serum cytokine and catecholamine levels were measured prior to lymphodepleting chemotherapy, on the day of CAR T infusion and daily thereafter while patients remained hospitalized. Tumor biopsies were taken within 1 month prior to CAR T infusion for evaluation of gene expression. RESULTS: We identified an association between pretreatment levels of IL6 and life-threatening CRS and NT. Because the risk of toxicity was related to pretreatment factors, we hypothesized that the tumor microenvironment (TME) may influence CAR T-cell toxicity. In pretreatment patient tumor biopsies, gene expression of myeloid markers was associated with higher toxicity. CONCLUSIONS: These results suggest that a proinflammatory state and an unfavorable TME preemptively put patients at risk for toxicity after CAR T-cell therapy. Tailoring toxicity management strategies to patient risk may reduce morbidity and mortality.