mepolizumab at a glance
Medicine class
Anti-interleukin-5 monoclonal antibody.
Main role
Specialist add-on treatment for selected conditions involving excessive eosinophilic inflammation.
Administration
Injection under the skin of the upper arm, abdomen or thigh.
Not a rescue treatment
It does not treat a sudden asthma or COPD flare-up.
What is mepolizumab used for?
The selected product information includes mepolizumab as add-on treatment for:
Severe refractory eosinophilic asthma in adults and children aged six years and over.
Severe chronic rhinosinusitis with nasal polyps in adults when systemic corticosteroids or surgery have not provided adequate control; intranasal corticosteroids are continued.
Uncontrolled COPD with an eosinophilic phenotype in adults already receiving appropriate inhaled maintenance treatment.
Relapsing-remitting or refractory eosinophilic granulomatosis with polyangiitis in people aged six years and over.
Inadequately controlled hypereosinophilic syndrome in adults without an identifiable non-haematological secondary cause.
How does mepolizumab work?
Interleukin-5 helps eosinophils develop, become active and survive. Mepolizumab binds to interleukin-5 and prevents it activating its receptor, reducing eosinophil-driven inflammation.
mepolizumab preparations and strengths
Injection
Route: Parenteral
Strengths: 40 mg, 100 mg
How to take mepolizumab
Mepolizumab is injected under the skin. Follow the product instructions and training supplied by the specialist team.
The powder vial must be reconstituted and administered by a healthcare professional.
The paediatric pre-filled syringe may be given by a healthcare professional or a trained caregiver when the clinical team considers this appropriate.
Suitable injection areas are the upper arm, abdomen or thigh.
Inspect a pre-filled syringe before use; do not use it if the liquid is cloudy, discoloured or contains particles.
Do not stop or reduce corticosteroids suddenly after starting mepolizumab; any reduction must be supervised.
mepolizumab side effects
Common or expected effects
- Headache
- Injection-site pain, redness, swelling, itching or burning
- Back or joint pain
- Sore throat or nasal congestion
- Upper abdominal discomfort
- Fever
- Eczema
- Respiratory or urinary tract infection
Get urgent medical advice
- Severe allergic reaction, including breathing difficulty, bronchospasm, facial or mouth swelling, hives, low blood pressure or collapse
- Asthma or COPD symptoms that become severely or rapidly worse require urgent assessment because mepolizumab is not a rescue treatment
mepolizumab in pregnancy
Human pregnancy information remains limited. Mepolizumab can be used when recommended by a specialist, particularly where maintaining control of severe asthma is important; the expected benefit and possible fetal risk should be assessed individually. Following exposure after the first trimester, the baby's live-vaccine schedule may need specialist review.
mepolizumab while breastfeeding
It is not known whether mepolizumab passes into human milk. The prescriber should assess the need for treatment alongside the benefits of breastfeeding, considering the infant's age and health; specialist breastfeeding-medicines advice may be appropriate for complex cases.
mepolizumab interactions
Formal interaction studies have not been performed, but clinically important pharmacokinetic interactions are considered unlikely because mepolizumab is not cleared through cytochrome P450 enzymes, transporters or protein-binding pathways. Patients should still tell their specialist about all medicines and supplements.
Common questions about mepolizumab
Answers are fully visible for fast scanning and source review.
Is mepolizumab a steroid?
No. It is a monoclonal antibody targeting interleukin-5. Existing corticosteroids should not be stopped or reduced without specialist supervision.
Can mepolizumab treat a sudden asthma attack?
No. Use the prescribed rescue plan and seek medical help if symptoms are severe or remain uncontrolled.
Why are eosinophil blood tests relevant to mepolizumab?
Mepolizumab targets eosinophil-driven inflammation. Blood eosinophil results, clinical history and the specific condition help specialists assess whether treatment is appropriate and whether it is having the intended biological effect.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.