What is Fasenra®?
Fasenra® (generic name: benralizumab) is a biologic medication designed to treat severe eosinophilic asthma and certain eosinophil-related conditions, such as Eosinophilic Granulomatosis with Polyangiitis (EGPA)
It belongs to the class of monoclonal antibodies that specifically target the interleukin-5 receptor alpha (IL-5Rα) on eosinophils. By binding to IL-5Rα, Fasenra helps the body eliminate eosinophils more effectively. This reduces airway inflammation and improves asthma control.
Why are Eosinophils Important in Asthma?
Eosinophils are a type of white blood cell that normally help fight infections and parasites. However, in some people, eosinophils become too numerous and trigger chronic inflammation, especially in the lungs.
This leads to severe eosinophilic asthma, a difficult-to-control condition where patients continue to have symptoms despite using inhaled corticosteroids and other standard therapies.
By targeting and depleting eosinophils, Fasenra helps reduce the inflammation that causes asthma symptoms such as wheezing, chest tightness, and frequent flare-ups.
Mechanism of Action – How Does Fasenra Work?
Fasenra contains benralizumab, a humanized afucosylated IgG1 kappa monoclonal antibody. It binds to the alpha subunit of the IL-5 receptor (IL-5Rα) on eosinophils and basophils.
- IL-5 is a cytokine responsible for eosinophil growth, survival, recruitment, and activation.
- By blocking IL-5Rα, Fasenra interrupts this signaling pathway.
- It triggers antibody-dependent cell-mediated cytotoxicity (ADCC), leading to the rapid and near-complete depletion of eosinophils.
The result: reduced airway inflammation, fewer asthma attacks, and better disease control
Approved Uses of Fasenra
Fasenra is FDA- and EMA-approved for the following conditions:
- Severe Eosinophilic Asthma
- For patients 12 years and older with high eosinophil counts (≥150 cells/µL).
- Used as an add-on maintenance treatment when standard asthma medications (such as inhaled corticosteroids + long-acting bronchodilators) are not enough.
- Helps reduce asthma exacerbations, ER visits, and hospital admissions.
- Not for treating sudden asthma attacks or life-threatening asthma (status asthmaticus).
- Eosinophilic Granulomatosis with Polyangiitis (EGPA)
- For adults with this rare type of eosinophil-related blood vessel inflammation.
- Helps control symptoms, reduce steroid use, and improve quality of life
How is Fasenra Given?
Fasenra is given as a subcutaneous injection (under the skin). It is available in prefilled syringes or autoinjectors.
Dosing schedule:
- For severe eosinophilic asthma:
- 30 mg every 4 weeks for the first 3 doses, then every 8 weeks thereafter.
- This less frequent dosing makes it more convenient than some other biologics.
- For EGPA:
- 30 mg every 4 weeks.
Where is it given?
- Usually administered in a clinic or hospital.
- Some patients may be trained to self-inject at home once deemed safe by their doctor.
How long should it be used?
- Treatment is usually long-term.
- Doctors reassess every 4–6 months to decide whether to continue.
Benefits of Fasenra
Patients receiving Fasenra often experience:
- Fewer asthma attacks (reduced exacerbation frequency).
- Less need for oral corticosteroids.
- Fewer ER visits and hospital admissions.
- Improved breathing, reduced wheezing, and less chest tightness.
- Better quality of life – being able to perform daily activities more easily
For EGPA patients, Fasenra may also help reduce symptoms affecting the lungs, skin, and nervous system.
Possible Side Effects
Like all medicines, Fasenra can cause side effects.
Common side effects:
- Headache
- Sore throat (pharyngitis)
- Fever or cold-like symptoms
- Injection site reactions (pain, redness, swelling)
Serious but rare side effects:
- Severe allergic reactions (anaphylaxis) – Patients should be observed after the first few injections.
- Infections – Some patients may have an increased risk of certain infections, though this is uncommon
Seek immediate medical help if you develop hives, facial swelling, chest tightness, wheezing, dizziness, or fainting after injection.
Safety Precautions
- Fasenra is not a rescue medication – it cannot replace inhalers, bronchodilators, or epinephrine during acute asthma attacks or allergic reactions.
- Patients should not stop using inhaled steroids or other prescribed asthma medications unless instructed by their doctor.
- Blood tests (especially eosinophil count) are usually done before starting Fasenra.
- Patients with weakened immune systems or active infections should discuss risks with their doctor before starting.
Frequently Asked Questions (FAQ)
Q: How often do I need injections?
A: Every 4 weeks for the first 3 doses, then every 8 weeks.
Q: Can I inject Fasenra at home?
A: Some patients can, but only after training and with doctor approval.
Q: How long will I need to take Fasenra?
A: Treatment is usually long-term, with periodic reassessments.
Q: Is Fasenra expensive?
A: Yes. It is a biologic medication, which typically costs more than standard inhalers. Prices depend on country, insurance, and hospital policies.
Key Takeaway
Fasenra® (Benralizumab) is a biologic injection that targets eosinophils, offering an advanced treatment for severe eosinophilic asthma and EGPA.
It reduces asthma flare-ups, lowers steroid dependence, and improves quality of life with the convenience of every 8-week dosing after initial treatment.
However, it is not an emergency medication and must be prescribed and monitored by a specialist.
