IL-6 Receptor Inhibitor Pregnancy: Avoid unless life-threatening — IgG1 antibody crosses placenta; neonatal immunosuppression possible; used in emergency ICU settings when benefit clearly outweighs risk

Tocilizumab (ICU — Cytokine Storm / COVID-19)

Brand names: RoActemra

Adult dose

Dose: 8 mg/kg IV single dose (max 800 mg); second dose at 12-24 hours if inadequate response

Route: Intravenous infusion over 60 minutes

Frequency: Single dose (± second dose); not repeated beyond 2 doses

Max: 800 mg per dose

COVID-19: hospitalised patients requiring supplemental oxygen with systemic inflammation (CRP ≥75 mg/L); given with dexamethasone; CAR-T cytokine release syndrome: 8 mg/kg IV (max 800 mg), repeat if needed

Paediatric dose

Dose: CRS: <30 kg: 12 mg/kg; ≥30 kg: 8 mg/kg IV (max 800 mg) mg/kg

Route: Intravenous

Frequency: Single dose (CRS management)

Max: 800 mg per dose

Licensed for CAR-T CRS in paediatrics; COVID-19 use in children specialist-guided

Dose adjustments

Renal

No dose adjustment required

Hepatic

Avoid in severe hepatic impairment

Paediatric weight-based calculator

Patient weight (kg)

Licensed for CAR-T CRS in paediatrics; COVID-19 use in children specialist-guided

Clinical pearls

RECOVERY trial tocilizumab results (Horby et al. NEJM 2021): tocilizumab reduced 28-day mortality by 4 percentage points in hospitalised COVID-19 with hypoxia + CRP ≥75 mg/L — benefit additive to dexamethasone; REMAP-CAP (NEJM 2021) confirmed benefit; now standard of care with dexamethasone
IL-6 storm pathophysiology: severe COVID-19 triggers cytokine release syndrome via unregulated IL-6 signalling — endothelial damage, ARDS, multiorgan failure; tocilizumab blocks IL-6Rα, interrupting the downstream JAK-STAT pathway
CRP interpretation after tocilizumab: IL-6R blockade suppresses CRP production (CRP is IL-6-dependent) — CRP falls dramatically within hours regardless of infection activity; do NOT use CRP to gauge infection severity for 48-72h post-tocilizumab; use procalcitonin instead
CAR-T CRS management: tocilizumab is first-line treatment for grade ≥2 CRS — should be immediately available at all CAR-T infusion centres; most effective if given early (grade 2-3); for refractory CRS or concurrent neurotoxicity (ICANS), add corticosteroids
Infection risk window: tocilizumab immunosuppression is profound but short-lived (single dose) — greatest infection risk in first 2-4 weeks; screen for latent TB and hepatitis B before use in non-emergency situations; in acute COVID-19 emergency, screen and treat after

Contraindications

Active serious infections (bacterial, fungal, viral)
Known hypersensitivity
Neutrophil count <0.5 × 10⁹/L
Platelet count <50 × 10⁹/L

Side effects

Infections (masking of fever — CRP/procalcitonin suppressed after tocilizumab)
Elevated transaminases
Hyperlipidaemia
Infusion reactions
GI perforation (rare)
Neutropenia

Interactions

Live vaccines — avoid
CYP3A4 substrates — IL-6 inhibition normalises CYP3A4; monitor ciclosporin, statins, warfarin after treatment

Monitoring

CRP, procalcitonin, FBC (do not use CRP to monitor infection post-dose)
LFTs (baseline and 4-6 weeks)
Blood glucose
Respiratory status (SpO2, FiO2 requirement)
Signs of GI perforation

Reference: BNFc; BNF 90; RECOVERY tocilizumab (Horby et al. NEJM 2021); REMAP-CAP (Gordon et al. NEJM 2021); MHRA SPC RoActemra; NICE TA878 (COVID-19); WHO COVID-19 Therapeutics 2023. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators