Makindo Medical Notes

🔗 Related Subjects: 🧠 Temporal (Giant Cell) Arteritis | 💉 Tocilizumab

📖 About

Always check the BNF entry for up-to-date dosing and safety information. Tocilizumab is a humanised anti-IL-6 receptor monoclonal antibody.

⚙️ Mode of Action

• 🧬 Humanised IgG1 antibody targeting IL-6 receptors (both soluble and membrane-bound).
• ⛔ Blocks IL-6 signalling → reduced CRP production, inflammation, and immune activation.
• 🌡️ Results in immunomodulation and reduced disease activity.

💊 Indications (Specialist Use)

• 🤲 Rheumatoid Arthritis: moderate–severe disease not controlled with DMARDs.
• 🧒 Systemic Juvenile Idiopathic Arthritis (sJIA): ≥2 years old.
• 🧠 Giant Cell Arteritis: active disease including cranial manifestations.
• 🧪 Cytokine Release Syndrome (CRS): post CAR-T cell therapy.
• 🦠 COVID-19: emergency use for severe systemic inflammation.

📌 Typical Doses (check BNF/SmPC for updates)

• 🤲 Rheumatoid Arthritis: IV 4 mg/kg every 4 weeks; SC 162 mg weekly or fortnightly.
• 🧒 sJIA: 8 mg/kg IV every 4 weeks.
• 🧠 GCA: 8 mg/kg IV or 162 mg SC weekly/fortnightly.
• 🧪 CRS: 8 mg/kg IV, may repeat after 8 hours if required.
• 🦠 COVID-19: 8 mg/kg IV (repeatable in 12–24 h if needed).

⚠️ Precautions

• 🧫 Screen for latent TB and hepatitis before initiation.
• 🧪 Monitor LFTs and FBC regularly.
• 🚫 Avoid use in active infections.
• ⚡ Use caution in diverticulitis (risk of GI perforation).
• 🔬 Monitor lipids, neutrophils, and platelets.

🔀 Interactions

• 💊 ↑ Risk of infection with other immunosuppressants.
• 🧩 May alter CYP450 metabolism → drug levels affected (e.g. warfarin, ciclosporin).
• 💉 Avoid live vaccines during therapy.

💥 Side Effects

• Common: 🤧 URTIs, 🤕 headache, 🩸 hypertension, 💉 injection-site reactions.
• Serious:
  • 🦠 Infections (including opportunistic).
  • 🧪 LFT elevation, hyperlipidaemia.
  • ⚡ GI perforations.
  • 🧬 Neutropenia, thrombocytopenia.
• Other: 📈 ↑ cholesterol/triglycerides, risk of malignancy, hypersensitivity reactions.

🔎 Cautions

• 🩺 CRP may be suppressed → infection/inflammation can be masked.
• 🧫 Treat latent TB before starting.
• 🧮 Stop if neutrophils <0.5 × 10⁹/L or platelets <50 × 10³/µL.

🚫 Contraindications

• ❌ Severe active infection.
• ❌ Baseline neutrophils <2 × 10⁹/L.

📚 References

• BNF – Tocilizumab