Mepolizumab
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A lab-made antibody that locks onto IL-5, a signaling protein that tells the body to make and sustain eosinophils — an immune cell that, in excess, drives inflammation in conditions like severe asthma.
How it works
Certain diseases flare up because the body makes too many eosinophils, immune cells that can cause swelling and irritation when there are too many of them. IL-5 is the chemical signal that tells the body to keep churning out and sustaining these cells. Mepolizumab works upstream by grabbing onto IL-5 itself, before it can deliver that signal. With the signal blocked, eosinophil levels in the blood drop sharply, usually within about a month.
What it’s used for
Added on top of existing treatment for people with severe asthma driven by high eosinophil counts, for adults with chronic sinus inflammation, and for adults with certain COPD. Also used on its own for two rarer conditions involving eosinophil overproduction.
- Mechanism
- IL-5 antagonist (mAb)
- Drug class
- Monoclonal antibody
- Therapeutic area
- Respiratory / Immunology