CAR-T & Cytokine Release Syndrome — Tocilizumab, ICANS & the ASTCT Grading

Also known as CAR-T cell therapy · Cytokine release syndrome · CRS

The CAR-T cell therapy (the chimeric antigen receptor T-cell — CD19 for the B-cell malignancies, BCMA for the myeloma) causes the cytokine release syndrome (CRS) — the IL-6-driven inflammatory storm of fever, hypotension, hypoxia (1 to 14 days post-infusion). The ASTCT grading: grade 1 fever; grade 2 hypotension not needing vasopressors or low-flow oxygen; grade 3 one vasopressor or high-flow oxygen; grade 4 multiple vasopressors or positive-pressure ventilation. The management: tocilizumab (anti-IL-6 receptor — 8 mg per kg, 12 mg per kg under 30 kg; the specific for the severe or life-threatening CRS); corticosteroids (for the grade 3 to 4 and for the ICANS). The ICANS (neurotoxicity — confusion, aphasia, seizures, cerebral oedema) is graded on the ICE score and treated first-line with dexamethasone 10 mg every 6 hours, because tocilizumab does not reach the CSF.

high19 referencesUpdated 26 July 202625 min readSource-verified · Sept 2026

Checked against its sources on 3 Sept 2026

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8 MCQs

The one-line answer

CAR-T cell therapy (the chimeric antigen receptor T-cell) causes cytokine release syndrome (CRS) — an IL-6-driven systemic inflammatory storm of fever, hypotension and hypoxia, 1 to 14 days after infusion — and ICANS, the neurotoxicity. Grade the CRS with the ASTCT criteria (grade 1 fever; grade 2 hypotension not requiring vasopressors or oxygen by low-flow nasal cannula; grade 3 hypotension requiring one vasopressor or oxygen by high-flow device; grade 4 multiple vasopressors or positive-pressure ventilation). Tocilizumab 8 mg per kg IV (12 mg per kg if under 30 kg — anti-IL-6 receptor; the only therapy specifically approved, for severe or life-threatening CAR-T CRS) is the specific for the CRS needing intervention; dexamethasone 10 mg IV every 6 hours is first-line for ICANS, because tocilizumab does not reach the cerebrospinal fluid.^[1]^[12]^[16]

Meet the patient

A 42-year-old man with refractory diffuse large B-cell lymphoma received axicabtagene ciloleucel (anti-CD19 CAR-T) five days ago. He now has fever 39.2, hypotension needing noradrenaline 0.15 micrograms per kg per min after 1 L of crystalloid, and high-flow nasal cannula at FiO2 0.5 for SpO2 94 per cent. He is dysarthric, cannot follow two-step commands, and has a fine tremor; ICE score 6 of 10. CRP 285, ferritin 45,000. He has CRS and ICANS at once.^[1]

Two questions decide every CAR-T admission: how sick is the systemic inflammation? (the ASTCT CRS grade — tocilizumab from grade 2) and is the brain involved? (the ICE score — dexamethasone for ICANS, because tocilizumab does not cross the blood-brain barrier). The two toxicities overlap, and the treatment of each is different. Hold both and the management slots into place.^[1]

References19Show

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