tocilizumab at a glance
Class
Interleukin-6 receptor-blocking monoclonal antibody.
Administration
Available as subcutaneous pens or syringes and as an intravenous infusion given by healthcare professionals.
Key safety point
Infections may be serious or less obvious because immune and inflammatory responses are suppressed.
What is tocilizumab used for?
Licensed uses depend on the formulation and individual product licence:
Rheumatoid arthritis in adults, commonly with methotrexate but sometimes alone when methotrexate is unsuitable.
Giant cell arteritis in adults using a licensed subcutaneous formulation.
Active systemic juvenile idiopathic arthritis.
Polyarticular juvenile idiopathic arthritis.
Severe or life-threatening cytokine release syndrome caused by CAR T-cell therapy, using the intravenous formulation.
COVID-19 in hospitalised adults receiving systemic corticosteroids who require supplemental oxygen or mechanical ventilation, using the intravenous formulation.
How does tocilizumab work?
Tocilizumab binds soluble and cell-surface interleukin-6 receptors, reducing inflammatory signalling. It also lowers C-reactive protein, which may make infection appear less inflammatory.
tocilizumab preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 20 mg/mL
Injection
Route: Parenteral
Strengths: 162 mg
How to take tocilizumab
Intravenous tocilizumab is diluted and administered by healthcare professionals. Subcutaneous treatment may be self-injected after suitability assessment and training.
Rotate injections between the recommended abdomen, thigh or upper-arm sites.
Do not inject into tender, bruised, red, hard, scarred, damaged or mole-containing skin.
Let the device reach room temperature as directed in its leaflet; do not shake it.
Check the solution and device before use and place used devices in an approved sharps container.
Follow the current product leaflet because storage and device instructions differ between brands.
tocilizumab side effects
Common or expected effects
- Upper respiratory infections or cold-like symptoms
- Headache or dizziness
- Injection-site redness, itching, pain or swelling
- Raised blood pressure
- Raised liver enzymes or cholesterol on blood tests
- Rash, itching or abdominal discomfort
Get urgent medical advice
- Serious infection, including pneumonia, shingles, sepsis or tuberculosis
- Severe allergic or infusion-related reaction
- Liver injury, potentially causing jaundice, marked tiredness or abdominal pain
- Diverticulitis or bowel perforation
- Severe reductions in neutrophils or platelets
- Severe blistering or peeling skin reaction
tocilizumab in pregnancy
Pregnancy evidence is limited. Product information advises use only when clearly necessary, following discussion with the specialist and maternity team. Later-pregnancy exposure may temporarily affect the baby's immune system, so tell the child's vaccination team because live-vaccine timing may need adjustment.
tocilizumab while breastfeeding
Evidence is limited. Cautious use with infant monitoring may be considered because transfer into milk and absorption by the infant are expected to be low. The decision should consider the mother's treatment needs, the infant's health and any pregnancy exposure.
tocilizumab interactions
Starting or stopping tocilizumab can alter the handling of some medicines, while immunosuppressive combinations may increase risk.
Warfarin and other individually adjusted CYP2C9 substrates
Exposure or effect may fall as inflammation resolves, so clinical and laboratory monitoring may need review.
Atorvastatin, simvastatin and other CYP3A4 substrates
Blood concentrations may fall after tocilizumab starts, and the effect can persist after it stops.
Theophylline, phenytoin or ciclosporin
These narrow-therapeutic-index medicines may require closer monitoring when tocilizumab is started or stopped.
Common questions about tocilizumab
Answers are fully visible for fast scanning and source review.
Is tocilizumab an immunosuppressant?
Yes. Blocking interleukin-6 signalling reduces immune-driven inflammation and can increase susceptibility to infection.
Can it hide signs of infection?
Yes. Fever, CRP and other inflammatory signs may be reduced, so new infection symptoms still require prompt assessment.
What blood tests are needed?
Monitoring commonly includes blood-cell counts, liver tests and cholesterol or other lipid measurements.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.