Extracorporeal cytokine removal in severe CAR-T cell associated cytokine release syndrome.

Purpose: Life-threatening complications of CD-19 Chimeric antigen receptor - T (CAR-T) cells such as the cytokine release syndrome (CRS)) have been reported. Treatment is limited to IL-6 blockade and steroids although global removal of elevated soluble inflammatory factors might be more effective.

Methods: Clinical course of a CRS patient treated with extracorporeal cytokine adsorption (Cytosorb®). A panel of 48 cytokines, chemokines and endothelial markers has been analyzed longitudinally. Ex vivo stimulation of endothelial cells to visualize (immunocytochemistry) and quantify (ECIS, TER) endothelial barrier effects.

Results: Following CAR-T cell application a 65 years old male developed grade 4 CRS with refractory shock (3 vasopressors) and severe capillary leakage (+37 L/24 h resuscitation). Treatment included IL-6 blockade, methylprednisolone and additionally Cytosorb hemoperfusion. While multiple soluble inflammatory factors were elevated and most of them decreased by more than 50% following Cytosorb, markers of endothelial injury increased steadily (e.g. Angpt-2/Angpt-1) leading to profound endothelial activation and leakage in ex vivo assays.

Conclusion: This is the first reported use of cytokine adsorption for CRS showing efficacy in absorption of various cytokines but not endothelial growth factors. A randomized controlled trial to evaluate additional Cytosorb treatment in CRS is currently recruiting at our institution (NCT04048434).