Mepolizumab

How it works

It binds circulating IL-5 and prevents it from engaging its receptor on eosinophils, reducing eosinophil production and survival and thereby dampening eosinophilic airway inflammation.

Prescribing in practice

• Not a treatment for acute bronchospasm or status asthmaticus and must never be used to relieve an acute asthma attack; patients should continue their usual reliever and controller therapy.
• Reserved for severe eosinophilic asthma confirmed by blood eosinophil criteria and prescribed within specialist severe-asthma services per NICE guidance.
• Treat any pre-existing helminth infection before starting, and consider hypersensitivity reactions which can occur during or after administration.

Monitoring

Monitor asthma control, exacerbation frequency and blood eosinophil count, and observe for hypersensitivity reactions after dosing.

Counselling the patient

• This injection is added to your usual inhalers to prevent attacks, not to treat one that is happening now.
• Keep using your reliever inhaler and seek urgent help if your breathing suddenly worsens.
• Report any rash, swelling or breathing difficulty after an injection.

Evidence & guidelines

NICE technology appraisal guidance supports mepolizumab as add-on therapy for severe refractory eosinophilic asthma in defined populations.