Makindo Medical Notes

⚠️ Active tuberculosis must be treated with standard therapy for at least 2 months before starting etanercept. Always check the BNF or local formulary before prescribing.

💊 About

• Anti–TNF-α agent: binds to soluble TNF receptors, blocking inflammatory signalling.
• Specialist use only (rheumatology, dermatology).
• Annual cost ≈ £9295 (assuming 52 doses/year).

🧬 Aetiology & Mechanism

• Comprises two soluble TNF-α receptor molecules fused with human IgG1 Fc fragment.
• Does not bind TNF-β receptors or membrane-bound TNF.
• ↓ Pro-inflammatory cytokine activity → improved disease control in autoimmune conditions.

⚠️ Concerns

• ↑ Risk of serious infections (esp. TB, fungal, opportunistic).
• Screen for latent TB, hepatitis B & C, HIV before initiation.
• Immunosuppression may mask signs of infection.

🎯 Indications

• Severe rheumatoid arthritis (RA).
• Moderate-to-severe plaque psoriasis.
• Severe ankylosing spondylitis.
• Active, progressive psoriatic arthritis.

💉 Dosing – Etanercept (check BNF/local datasheet)

🚫 Contraindications

• Active infection (incl. sepsis, chronic or localised infections).
• Do not initiate in untreated latent/active TB.

⚠️ Side Effects

• Injection site reactions (pain, erythema).
• Serious infections (TB, sepsis, pneumonia).
• Blood disorders (pancytopenia, aplastic anaemia).
• CNS demyelination (rare).
• GI upset, headache, rash.

📚 References

• Summary of Product Characteristics
• NICE TA375: Biologics for RA (2016)

💡 Pearls:
- Always screen for latent TB & hepatitis B before starting.
- Combine with methotrexate in RA for maximal efficacy.
- Monitor for infection, cytopenias, demyelination during therapy.