Hemoadsorption as a Supportive Strategy for Severe Toxicity Associated With Chimeric Antigen Receptor T-Cell Therapy: A Case Series

Rationale & Objective: To describe the use and effects of extracorporeal blood purification with hemoadsorption in managing severe complications after treatment with chimeric antigen receptor T-cells (CAR-T). Study Design: Retrospective analysis of a case series. Setting & Participants: Hematological department and intensive care unit from a single institution. Patients with hematological cancer who underwent CAR-T therapy between 2021 and 2023, developed severe toxicity, and were treated with hemoadsorption based on clinical indications. Results: Of 48 patients, extracorporeal blood purification was prescribed to 4 (8.3%): 3 with diffuse large B-cell lymphoma and 1 with mantle cell lymphoma. These patients experienced rapid increases in serum interleukin-6 and ferritin levels after CAR-T infusion, which progressed to severe cytokine release syndrome with hemodynamic instability and multiple-organ toxicity. Despite corticosteroid and anakinra rescue therapy after tocilizumab failure, extracorporeal blood purification with hemoadsorption was initiated at a mean of 5.2 ± 1.7 days following CAR-T infusion due to rapid clinical deterioration. The treatment was performed using continuous venovenous hemodiafiltration with an AN69ST hemofilter and a CytoSorb cartridge. One patient died 1 day after the initiation of blood purification because of concomitant cardiomyopathy progressing to multiple-organ failure. In the 3 surviving patients, interleukin-6 levels significantly decreased (from −18% to −95%), cytokine release syndrome resolved, and vasoactive support was reduced. Treatment-related complications were not observed. Limitations: Small sample size, retrospective design, and lack of a predefined hemoadsorption therapy protocol. Conclusions: A strategy based on hemoadsorption was safe and effective in mitigating inflammation and improving hemodynamics in patients with hematological cancer treated with CAR-T therapy who developed early severe toxicity. Plain Language Summary: Chimeric antigen receptor T-cell (CAR-T) therapy may improve remission rates and survival in hematological cancers but can lead to severe side effects, including cytokine release syndrome (CRS). CRS is characterized by systemic inflammation and multiorgan toxicity and is often associated with poor outcomes. Although pharmacological treatments are available, some cases remain refractory. In this study, we share our experience with hemoadsorption as a supportive therapy for severe CRS in CAR-T recipients. Of the 4 patients treated, 3 experienced CRS resolution with reduced inflammation and improved hemodynamic stability, without treatment-related complications. These findings highlight hemoadsorption as a promising adjunctive therapy to pharmacological treatments for managing severe CAR-T toxicities. Further research is needed to confirm these results.