Fasenra (benralizumab) is an injectable biologic medication that's used to treat severe eosinophilic asthma in people 6 years and older. It belongs to a class of medications called interleukin antagonists. Fasenra (benralizumab) is available as a pen that you can inject at home, either by yourself or with the help of a caregiver. The usual dosing is to inject under the skin every month for the first 3 months, and then every 2 months after that. Common side effects include headache and sore throat.
Add-on treatment for severe eosinophilic asthma in people 6 years and older
Fasenra (benralizumab) is an interleukin antagonist. It blocks interleukin-5 (IL-5), a protein that normally makes white blood cells called eosinophils. Having high levels of eosinophils in the body can lead to inflammation, which plays a role in asthma.
While the exact way Fasenra (benralizumab) works to treat asthma isn't fully understood, it's known that the medication reduces the level of eosinophils in the body. This is thought to lessen inflammation in the lungs, which helps to ease symptoms of severe asthma.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Maintenance dose is injected every 2 months
Shown to lower the rate of asthma attacks
Available as a pre-filled pen so you can inject conveniently at home
Can't treat asthma attacks
Needs to be injected, which can be inconvenient compared to pills or an inhaler
Not approved for children under 6 years old
Don't give yourself or your child Fasenra (benralizumab) injections until you understand how to prepare and inject a dose. Your provider will also show you how to do your first injection.
If you're taking corticosteroids or other asthma medications, continue to take them while taking Fasenra (benralizumab) according to your provider's treatment plan. Suddenly stopping or changing how you take these medications can cause serious steroid withdrawal symptoms.
Speak with your provider right away if you become pregnant while receiving Fasenra (benralizumab). It's not clear whether this medication is safe for people who are pregnant. Your provider can discuss the risks and benefits of taking Fasenra (benralizumab) and other safe treatment for you.
Throw away your used syringes and pens in a sharps disposal container after each use. Check out the FDA page for more information about disposing your sharps.
Store Fasenra (benralizumab) in the refrigerator in its original container. When it's time for your dose, take the medication out of the refrigerator and let it come to room temperature (30 minutes) before you inject it. If you accidentally left the medication out of the refrigerator, you must use it within 14 days.
Fasenra (benralizumab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
People who received Fasenra (benralizumab) have sometimes experienced life-threatening allergic reactions. These reactions can happen within hours to days after your injection. Watch out for signs and symptoms of allergic reactions, such as rash, trouble breathing, swelling in your face, itching, redness, dizziness, and joint pain. Stop Fasenra (benralizumab) and get medical attention right away if an allergic reaction occurs.
Fasenra (benralizumab) shouldn't be used to treat asthma attacks or any severe episodes of asthma. You should only use a rescue inhaler, such as albuterol (ProAir), to treat asthma attacks. If your rescue inhaler isn't working well to control your symptoms of wheezing or shortness of breath, get medical attention right away. You might need additional medications, such as steroid pills to help with your symptoms.
It's very important that you continue taking your steroid therapy according to your provider's treatment plan even if you're using Fasenra (benralizumab). Missing doses or stopping corticosteroids suddenly can cause withdrawal symptoms that can be dangerous.
Because Fasenra (benralizumab) works to reduce your white blood cell levels, it might lower your ability to fight infections. If you happen to have a parasitic worm infection, your provider might treat the infection first before starting this medication. If you get an infection while taking Fasenra (benralizumab), your provider might pause the medication until your infection gets better.
Adults and children 12 years of age and older: The typical starting dose is 30 mg injected under the skin every month for the first 3 months. After that, the typical maintenance dose is 30 mg injected under the skin every 2 months.
Children 6 to 11 years of age
Weigh 77 lbs or more: The typical starting dose is 30 mg injected under the skin every month for the first 3 months. After that, the typical maintenance dose is 30 mg injected under the skin every 2 months.
Weigh less than 77 lbs: The typical starting dose is 10 mg injected under the skin every month for the first 3 months. After that, the typical maintenance dose is 10 mg injected under the skin every 2 months.
Add-on treatment for severe eosinophilic asthma in people 6 years and older
Moderate-to-severe eczema - for people 6 months and older
Moderate-to-severe asthma - add-on maintenance for people 6 years and older
Long-term sinus congestion with nasal polyps - add-on maintenance for people 12 years and older
Eosinophilic esophagitis - for people 1 year and older
Prurigo nodularis (long-term itchy skin bumps) - for adults
Chronic obstructive pulmonary disease (COPD) - add-on maintenance for adults
Long-term hives - for people 12 years and older
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Al Amin, A. S. M., et al. (2023). Helminthiasis. StatPearls.
Asthma and Allergy Foundation of America. (2024). Understanding eosinophilic asthma.
AstraZeneca. (2024). Instructions for Use - Fasenra Pen™ (fas-en-rah) (benralizumab), for subcutaneous injection; single-dose autoinjector.
AstraZeneca Pharmaceuticals LP. (2024). Fasenra- benralizumab injection, solution [package insert]. DailyMed.
Criner, G J., et al. (2019). Benralizumab for the prevention of COPD exacerbations. New England Journal of Medicine.
Pelaia, C., et al. (2019). Interleukin-5 in the pathophysiology of severe asthma. Frontiers in Physiology.
Singh, D., et al. (2023). Benralizumab prevents recurrent exacerbations in patients with chronic obstructive pulmonary disease: A post hoc analysis. International Journal of Chronic Obstructive Pulmonary Disease.
U.S. Food and Drug Administration. (2021). Safely using sharps (needles and syringes) at home, at work and on travel.
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