Fasenra (benralizumab)

What it is

Fasenra (benralizumab) is a biologic medicine for adults with EGPA (eosinophilic granulomatosis with polyangiitis) — a rare type of vasculitis, which means inflammation of the blood vessels. In EGPA, a type of white blood cell called an eosinophil builds up in the blood and tissues and damages the lungs, sinuses, skin, and nerves. Fasenra attaches to eosinophils and removes nearly all of them from the blood, which helps calm the disease and can allow steroid doses to be lowered. It is also used for severe eosinophilic asthma.

Before starting

Before starting, we check a blood count to confirm your eosinophil level, and review any parasite (helminth) infections — eosinophils are part of the body’s defence against parasites, so a known parasite infection should be treated before this medicine removes those cells. Tell us about allergies to medicines, because people who have had a serious allergic reaction to Fasenra cannot continue it. If you are on steroids for EGPA, do not reduce or stop them on your own when starting Fasenra — steroid tapering is done gradually and only under your provider’s direction, because dropping steroids too fast can cause its own problems.

How it’s given

For EGPA, it is a single injection under the skin once every 4 weeks, given with a pre-filled pen at home or in our office. (For asthma, the schedule differs — the first three doses every 4 weeks, then every 8 weeks.) If you inject at home, use the thigh or belly, rotate sites, store the pen in the refrigerator, and let it warm to room temperature for about 30 minutes before use so it is more comfortable.

What to expect

Eosinophil counts fall within days, but the benefits that matter — fewer EGPA flares, better breathing and sinus symptoms, and the ability to taper steroids — build over the following months, and are usually judged over 3–6 months. The most common side effects are headache and sore throat; injection-site soreness can occur. Serious allergic reactions are uncommon but possible — seek urgent care for swelling of the face or tongue, widespread rash, or trouble breathing after a dose. Because EGPA itself can flare during steroid tapers, report new numbness, weakness, rash, or worsening asthma promptly rather than waiting for the next visit.

Everyday guidance

If you miss a dose, take it as soon as you remember and then continue every 4 weeks from there. Do not adjust your steroids yourself — dose changes are planned with your provider at each step of a taper. Keep a simple note of symptoms between visits (breathing, sinus congestion, skin, numbness or tingling); that record helps us judge how the disease is responding. Tell other clinicians you use an eosinophil-lowering biologic. Questions: call the office at (361) 400-7700.