omalizumab at a glance
Medicine class
Humanised anti-IgE monoclonal antibody
Licensed uses
Selected severe allergic asthma, severe chronic rhinosinusitis with nasal polyps, and chronic spontaneous urticaria
How it is given
Injection into the fatty layer beneath the skin
Home administration
Some people without a history of anaphylaxis can inject at home after supervision, training and clinician approval
What is omalizumab used for?
Licensed uses represented by the selected product are:
Add-on treatment for confirmed severe persistent allergic asthma that remains inadequately controlled despite established asthma treatment.
Add-on treatment with an intranasal corticosteroid for adults with severe chronic rhinosinusitis with nasal polyps that remains inadequately controlled.
Add-on treatment for adults and adolescents with chronic spontaneous urticaria that has responded inadequately to an H1 antihistamine.
How does omalizumab work?
Omalizumab binds free IgE before it can attach to high-affinity IgE receptors on mast cells and basophils. This reduces activation of allergic inflammation. In chronic spontaneous urticaria, its full mechanism is not completely understood.
omalizumab preparations and strengths
Injection
Route: Parenteral
Strengths: 75 mg, 150 mg, 300 mg
How to take omalizumab
Omalizumab is injected under the skin, not into a vein or muscle. Initial injections are supervised by a healthcare professional; home injection is appropriate only after training and clinician approval.
Follow the device-specific leaflet and inject the full prescribed amount.
Allow an unopened syringe to reach room temperature naturally; do not use a microwave, hot water or another heat source.
Do not use a syringe if it is damaged, expired, discoloured, distinctly cloudy or contains particles.
Suitable sites include the front of the thighs or lower abdomen; a caregiver may also use the outer upper arm. Avoid bruised, tender, scarred, red or damaged skin.
Put used syringes directly into an approved sharps container.
omalizumab side effects
Common or expected effects
- Injection-site pain, redness, swelling or itching
- Headache
- Upper abdominal pain
- Joint pain
- Dizziness
- Fever, particularly in children
- Upper respiratory tract infection or sinus symptoms
Get urgent medical advice
- Severe immediate or delayed allergic reaction, including anaphylaxis
- Serum sickness-like reaction with fever, rash, swollen glands and joint pain or swelling
- Low platelet count, which may cause unusual bruising or bleeding
- Eosinophilic inflammation or vasculitis, with worsening breathing, rash, heart symptoms, numbness or tingling
- Systemic lupus erythematosus-like symptoms
omalizumab in pregnancy
Omalizumab may be used during pregnancy when recommended by a specialist. Available studies have not identified an increased risk of pregnancy problems, but evidence remains limited. If exposure occurs after the first trimester, maternity and paediatric teams should consider whether the baby's live vaccines need to be delayed.
omalizumab while breastfeeding
Omalizumab can be considered during breastfeeding when clinically needed. Only very small amounts are expected to reach milk, and absorption by the infant's gut is likely to be minimal; discuss treatment with the specialist or prescriber.
omalizumab interactions
Omalizumab has little potential for conventional metabolic interactions, although formal medicine and vaccine interaction studies are limited.
Medicines for parasitic worm infections
Omalizumab may reduce their effectiveness; specialist review is appropriate if an infection does not respond as expected.
Corticosteroids and other existing asthma or nasal treatments
Omalizumab is add-on treatment; corticosteroids should not be stopped abruptly and any reduction must be clinician-led.
Allergen immunotherapy
Experience with the combination is limited, so it should remain under specialist supervision.
Common questions about omalizumab
Answers are fully visible for fast scanning and source review.
Is omalizumab a steroid?
No. It is a biological monoclonal antibody that targets IgE.
Does omalizumab replace my inhalers, antihistamines or nasal spray?
Usually not. It is licensed as add-on treatment, and existing treatments should only be changed by the treating clinician.
Can omalizumab treat a sudden asthma attack?
No. It does not relieve acute bronchospasm or status asthmaticus; use the prescribed emergency asthma plan and seek urgent help when required.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.