Fasenra (Benralizumab)
Monoclonal Antibody for Severe Eosinophilic Asthma and EGPA
Quick Facts About Fasenra
Key Takeaways
- Fasenra is a biologic therapy that targets the IL-5 receptor on eosinophils, leading to their rapid and near-complete depletion from blood and tissues.
- It is approved for severe eosinophilic asthma (as add-on therapy) and eosinophilic granulomatosis with polyangiitis (EGPA) in adults aged 18 and over.
- The standard dosing regimen for asthma is 30 mg subcutaneously every 4 weeks for the first three doses, then every 8 weeks; for EGPA, it is 30 mg every 4 weeks.
- Fasenra is not a rescue medication and should never be used to treat acute asthma attacks or bronchospasm.
- Common side effects include headache, sore throat, fever, and injection site reactions; serious allergic reactions are rare but possible.
What Is Fasenra and What Is It Used For?
Fasenra contains the active substance benralizumab, a humanised, afucosylated monoclonal antibody produced in Chinese hamster ovary cells by recombinant DNA technology. It belongs to a class of medications known as biologic therapies – precisely engineered proteins designed to target specific components of the immune system. In the case of benralizumab, the target is the interleukin-5 receptor alpha (IL-5Rα), a protein found predominantly on the surface of eosinophils and basophils.
Eosinophils are a type of white blood cell that plays an important role in the body’s immune defence against parasites. However, in conditions such as severe eosinophilic asthma and EGPA, eosinophil numbers become abnormally elevated in the blood and tissues, driving chronic inflammation that damages the airways and, in the case of EGPA, blood vessels and other organs. By binding to the IL-5 receptor, benralizumab triggers a process called enhanced antibody-dependent cell-mediated cytotoxicity (ADCC), which recruits natural killer cells to directly destroy eosinophils. This mechanism leads to rapid and near-complete depletion of eosinophils, typically within 24 hours of the first dose.
Severe Eosinophilic Asthma
Fasenra is indicated as add-on maintenance treatment for severe eosinophilic asthma in adults whose disease is inadequately controlled despite treatment with high-dose inhaled corticosteroids (ICS) combined with long-acting beta-agonists (LABA) and potentially other controller medications. Eosinophilic asthma is characterised by elevated blood eosinophil counts (typically ≥300 cells/μL) and accounts for approximately 50–60% of severe asthma cases, according to data from the International Severe Asthma Registry (ISAR).
Clinical trials have demonstrated that Fasenra significantly reduces the rate of asthma exacerbations in patients with severe eosinophilic asthma. In the pivotal SIROCCO and CALIMA trials, benralizumab reduced exacerbation rates by up to 51% compared to placebo in patients with baseline blood eosinophil counts ≥300 cells/μL. Furthermore, the ZONDA study showed that Fasenra enabled a median 75% reduction in oral corticosteroid dose, with 52% of patients completely eliminating oral corticosteroid use while maintaining asthma control.
For patients with severe asthma who rely on daily oral corticosteroids, the ability to reduce or discontinue these medications is clinically significant, as long-term oral corticosteroid use is associated with serious adverse effects including osteoporosis, diabetes, adrenal suppression, and increased infection risk.
Eosinophilic Granulomatosis with Polyangiitis (EGPA)
Fasenra is also approved for the treatment of EGPA in adults. EGPA, formerly known as Churg-Strauss syndrome, is a rare systemic vasculitis characterised by eosinophilic infiltration of tissues and inflammation of small- to medium-sized blood vessels. The condition typically affects the lungs and sinuses but can also involve the skin, heart, kidneys, gastrointestinal tract, and peripheral nervous system.
In the Phase III MANDARA trial, benralizumab demonstrated non-inferiority to mepolizumab (another anti-IL-5 biologic) in achieving remission in EGPA patients. Treatment with Fasenra significantly reduced eosinophil counts and allowed patients to taper their oral corticosteroid doses while maintaining disease control. The ability to reduce corticosteroid dependence is particularly important in EGPA, as patients often require prolonged courses of high-dose corticosteroids that carry substantial long-term toxicity.
How Fasenra Works
Unlike other anti-eosinophil biologics (such as mepolizumab and reslizumab) that target the IL-5 ligand itself, benralizumab binds directly to the IL-5 receptor alpha subunit on the eosinophil surface. This unique mechanism has two important consequences. First, it prevents IL-5 from signalling the eosinophil to survive, proliferate, and activate. Second, because benralizumab is engineered without fucose sugar residues on its Fc region (afucosylated), it has enhanced affinity for the FcγRIIIa receptor on natural killer (NK) cells. This enhanced binding triggers potent ADCC, leading to direct apoptosis (programmed cell death) of the eosinophil. The result is a more rapid and more complete eosinophil depletion compared to anti-IL-5 ligand antibodies.
What Should You Know Before Taking Fasenra?
Contraindications
Fasenra must not be used if you have a known hypersensitivity (allergy) to benralizumab or any of the excipients in the formulation. These excipients include histidine, histidine hydrochloride monohydrate, trehalose dihydrate, polysorbate 20 (E 432), and water for injections. If you have experienced an allergic reaction to any of these substances in the past, inform your healthcare provider before starting Fasenra.
Polysorbate 20 is a plant-derived excipient present in the formulation at a concentration of 0.06 mg per 30 mg pre-filled pen. Although allergic reactions to polysorbates are uncommon, patients with known polysorbate sensitivity should discuss this with their prescribing physician.
Warnings and Precautions
Before starting Fasenra, inform your doctor, nurse, or pharmacist about any of the following conditions, as they may affect whether Fasenra is appropriate for you or require additional monitoring:
- Parasitic infections: Because eosinophils play a role in the immune response against certain parasites (helminths), depleting eosinophils with Fasenra may impair your ability to fight parasitic infections. If you currently have a parasitic infection, it should be treated before starting Fasenra. If you live in or travel to areas where parasitic infections are endemic, discuss this with your doctor.
- Previous allergic reactions: If you have previously experienced an allergic reaction to an injection or a biologic medicine, inform your healthcare provider. Although uncommon, serious allergic reactions including anaphylaxis have been reported with Fasenra.
- Uncontrolled asthma: If your asthma worsens or remains uncontrolled during treatment with Fasenra, contact your doctor promptly. Fasenra is not effective in all patients, and your treatment plan may need adjustment.
Fasenra is not a rescue medication. It should never be used to treat acute asthma attacks, sudden episodes of breathlessness, or acute bronchospasm. Always keep your reliever inhaler (e.g. salbutamol) available for emergency use. If you experience sudden worsening of your breathing, use your rescue inhaler and seek immediate medical attention.
Allergic Reactions
Fasenra can potentially cause serious allergic reactions (hypersensitivity reactions), including anaphylaxis. These reactions may occur within hours or days after injection. Symptoms of a serious allergic reaction include urticaria (hives), skin rash, difficulty breathing, fainting, dizziness, light-headedness, and swelling of the face, tongue, or mouth. If you experience any of these symptoms, seek immediate medical attention.
It is important that you discuss with your doctor how to recognise the early signs of a serious allergic reaction and what actions to take if one occurs. Your healthcare provider will typically monitor you for a period after the first few injections to watch for any allergic response.
Other Medications
Do not suddenly stop taking or change the dose of your other asthma or EGPA medications when you start Fasenra. If your response to treatment allows it, your doctor may gradually reduce the dose of some of your other medications, particularly oral corticosteroids. This tapering must be done gradually and under direct medical supervision to avoid adrenal crisis or disease flare.
Inform your doctor about all medications you are currently taking, have recently taken, or may be planning to take. Although no formal drug interaction studies have been conducted with benralizumab, its mechanism of action (targeting IL-5Rα on eosinophils) suggests that clinically significant pharmacokinetic interactions with other medications are unlikely. Monoclonal antibodies are not metabolised by cytochrome P450 enzymes and do not typically affect the metabolism of small-molecule drugs.
Children and Adolescents
Fasenra is not approved for use in children and adolescents under 18 years of age for the treatment of asthma or EGPA. The safety and efficacy of benralizumab have not been established in this population. Clinical trials to evaluate paediatric use are ongoing, but until data are available, Fasenra should not be given to patients younger than 18 years.
Pregnancy and Breastfeeding
If you are pregnant, think you may be pregnant, or are planning to become pregnant, consult your doctor before using Fasenra. The safety of benralizumab during pregnancy has not been established in adequately controlled human studies. As a monoclonal antibody (IgG1), benralizumab is expected to cross the placental barrier, particularly during the second and third trimesters. Animal reproductive studies have not revealed direct harmful effects on foetal development, but the absence of human data means that Fasenra should only be used during pregnancy if the potential benefit clearly justifies the potential risk to the foetus.
It is not known whether benralizumab or its metabolites are excreted in human breast milk. Human immunoglobulins (IgG) are known to be present in breast milk, so excretion of benralizumab into breast milk cannot be excluded. If you are breastfeeding or planning to breastfeed, discuss the benefits and risks with your doctor before starting or continuing Fasenra.
Driving and Operating Machinery
Fasenra is unlikely to affect your ability to drive or use machines. No studies on the effect on driving ability have been performed, but based on the pharmacological properties of benralizumab, no impairment is expected.
How Does Fasenra Interact with Other Drugs?
Benralizumab is a monoclonal antibody that is cleared through intracellular catabolism (protein degradation) rather than through hepatic cytochrome P450 (CYP) enzyme pathways. This means it does not compete with small-molecule drugs for metabolic clearance and is therefore unlikely to cause traditional pharmacokinetic drug interactions. No formal interaction studies have been conducted, and no dose adjustments of concomitant medications are generally required when starting Fasenra.
However, there are important clinical considerations regarding the use of Fasenra with other medications, particularly in the context of severe asthma and EGPA management:
| Drug / Drug Class | Consideration | Clinical Guidance |
|---|---|---|
| Oral corticosteroids (e.g. prednisolone, prednisone) | Fasenra may enable reduction of oral corticosteroid dose, but tapering must be gradual to avoid adrenal insufficiency | Only reduce under medical supervision; monitor for signs of adrenal crisis |
| Inhaled corticosteroids + LABA (e.g. fluticasone/salmeterol) | Must be continued as prescribed; Fasenra is an add-on therapy, not a replacement | Do not stop or reduce without doctor’s instruction |
| Other biologic therapies (e.g. omalizumab, mepolizumab, dupilumab) | Concurrent use with other biologics has not been studied and is generally not recommended | Avoid combining biologics without specialist guidance |
| Immunosuppressants (e.g. methotrexate, azathioprine, cyclophosphamide) | Eosinophil depletion adds to overall immunosuppressive burden; combined use may increase infection risk | Monitor for infections; discuss risk–benefit with specialist |
| Live vaccines | Although not formally studied, the immunosuppressive effect of eosinophil depletion could theoretically reduce vaccine efficacy or increase risk | Discuss vaccination timing with your doctor; inactivated vaccines are generally safe |
| Anti-parasitic medications (e.g. albendazole, ivermectin) | Eosinophil depletion may impair immune response to parasitic infections; treat existing infections before starting Fasenra | Complete anti-parasitic treatment prior to initiating benralizumab |
While Fasenra does not interfere with the pharmacokinetics of most medications, clinicians should consider the overall immunological impact of eosinophil depletion, especially in patients receiving other immunomodulatory or immunosuppressive agents. Regular monitoring for infections and overall immune function is recommended in patients on complex medication regimens.
What Is the Correct Dosage of Fasenra?
Fasenra should always be used exactly as prescribed by your doctor. The medication is available as a pre-filled pen (Fasenra Pen) containing 30 mg of benralizumab in 1 mL of solution. Each pen is for single use only.
Adults with Severe Eosinophilic Asthma
Asthma Dosing Schedule
Loading phase: 30 mg subcutaneous injection every 4 weeks for the first 3 doses (at weeks 0, 4, and 8).
Maintenance phase: 30 mg subcutaneous injection every 8 weeks thereafter, starting from week 16.
Treatment response should be assessed after at least 4 months. If there is no improvement in asthma control, your doctor may reconsider continued treatment with Fasenra.
Adults with EGPA
EGPA Dosing Schedule
Dosing: 30 mg subcutaneous injection every 4 weeks (no change in frequency over time).
Treatment should be continued as long as the physician deems it clinically appropriate for controlling the disease and reducing corticosteroid dependence.
Administration
Fasenra is administered as a subcutaneous (under the skin) injection. The recommended injection sites are the front of the thigh or the lower abdomen (at least 5 cm from the navel). A caregiver may also administer the injection into the upper arm. You should rotate injection sites and avoid injecting into areas where the skin is tender, bruised, scaly, hardened, scarred, or damaged.
You and your doctor should decide whether you can self-inject Fasenra. Self-injection should not be attempted if you have not been previously treated with Fasenra or if you have a history of allergic reactions to Fasenra. Proper training in the correct injection technique must be provided before self-administration begins. The Fasenra Pen should be allowed to reach room temperature (20–25°C) for approximately 30 minutes before use. Do not use a microwave, hot water, or other heat sources to warm the pen.
| Indication | Dose | Frequency | Route |
|---|---|---|---|
| Severe eosinophilic asthma (loading phase) | 30 mg | Every 4 weeks (3 doses) | Subcutaneous injection |
| Severe eosinophilic asthma (maintenance) | 30 mg | Every 8 weeks | Subcutaneous injection |
| EGPA | 30 mg | Every 4 weeks | Subcutaneous injection |
Missed Dose
If you miss a scheduled dose of Fasenra, contact your doctor, pharmacist, or nurse as soon as possible to arrange a replacement injection. Do not attempt to administer a double dose to make up for a missed one. Your doctor will advise on the best schedule to resume your regular dosing pattern.
Stopping Treatment
Do not stop treatment with Fasenra unless your doctor advises you to do so. Discontinuing Fasenra may cause your asthma symptoms and exacerbations to return, or your EGPA symptoms to flare. If your asthma symptoms worsen while receiving Fasenra injections, contact your doctor for assessment. The benefits of Fasenra are maintained only with continued use, as eosinophil levels will return to pre-treatment levels once the medication is discontinued.
To facilitate traceability of biological medicines, the brand name and batch number of Fasenra should be recorded each time a new pack is dispensed. Keep this information available and share it when reporting any adverse effects.
What Are the Side Effects of Fasenra?
Like all medicines, Fasenra can cause side effects, although not everyone experiences them. Most side effects are mild to moderate in severity and tend to resolve without specific treatment. Below is a summary of reported side effects organised by frequency, based on clinical trial data and post-marketing surveillance.
Common
May affect up to 1 in 10 people
- Headache
- Pharyngitis (sore throat)
- Pyrexia (fever)
- Injection site reactions (pain, redness, itching, swelling, or warmth at the injection site)
- Hypersensitivity reactions (urticaria/hives, skin rash)
Rare / Frequency Not Known
Reported from post-marketing surveillance; exact frequency cannot be determined
- Anaphylaxis (severe, potentially life-threatening allergic reaction)
- Angioedema (swelling of face, tongue, or mouth)
- Severe difficulty breathing due to allergic reaction
- Hypotension (low blood pressure) associated with allergic reaction
- Fainting, dizziness, or light-headedness related to blood pressure drop
If you experience any signs of a severe allergic reaction – including swelling of the face, tongue, or throat, difficulty breathing, rapid heartbeat, dizziness, fainting, or widespread hives – seek emergency medical care immediately. These reactions can occur within hours or days after an injection of Fasenra.
In the pivotal clinical trials (SIROCCO, CALIMA, and ZONDA), the overall safety profile of benralizumab was comparable to placebo. Injection site reactions were generally mild and resolved within a few days without intervention. The incidence of serious adverse events was similar between the benralizumab and placebo groups.
Long-term extension studies (BORA and MELTEMI) have confirmed the sustained safety profile of Fasenra over treatment periods exceeding 5 years. No new safety signals were identified with prolonged use, and the rates of serious infections, malignancies, and cardiovascular events remained comparable to background rates in the severe asthma population.
It is important to report any suspected side effects to your healthcare provider. Reporting helps regulatory authorities continuously monitor the benefit-risk balance of medications. Adverse events can be reported through national pharmacovigilance systems, such as the FDA MedWatch programme in the United States, the MHRA Yellow Card scheme in the United Kingdom, or the EMA EudraVigilance system in Europe.
How Should You Store Fasenra?
Proper storage of Fasenra is essential to maintain its effectiveness and safety. As a biologic medicine containing a monoclonal antibody, benralizumab is sensitive to temperature extremes, light, and physical agitation. Follow these storage guidelines carefully:
- Refrigeration: Store Fasenra in a refrigerator at 2°C to 8°C (36°F to 46°F). Keep the pen in its original carton to protect from light.
- Room temperature storage: Fasenra may be stored at room temperature (up to 25°C / 77°F) for a maximum of 14 days. Once removed from the refrigerator, the pen must be used within 14 days or discarded. Note the discard date on the carton when removing from the refrigerator.
- Do not freeze: Freezing can damage the protein structure of benralizumab and render the medicine ineffective. If the pen has been frozen, discard it and use a new one.
- Do not shake: Shaking can cause protein aggregation and foaming, which may affect the quality and tolerability of the injection.
- Do not heat: Do not use a microwave, hot water, or any external heat source to warm the pen. Allow it to reach room temperature naturally for approximately 30 minutes before injection.
- Check before use: Inspect the solution through the inspection window before each injection. The liquid should be clear to slightly yellow and may contain small white particles. Do not inject if the solution is cloudy, discoloured, or contains large particles.
- Expiry date: Do not use Fasenra after the expiry date printed on the label and carton (EXP). The expiry date refers to the last day of that month.
- Single use only: Each Fasenra Pen is intended for a single injection only. Do not reuse or share pens.
Keep Fasenra out of the sight and reach of children. Do not dispose of used pens in household waste. Place used pens in an appropriate sharps disposal container immediately after use. Ask your pharmacist how to dispose of medicines and sharps containers that are no longer needed.
What Does Fasenra Contain?
Each Fasenra Pen contains a single dose of 30 mg benralizumab dissolved in 1 mL of sterile, preservative-free solution. Below is a complete list of all ingredients in Fasenra:
| Ingredient | Type | Function |
|---|---|---|
| Benralizumab | Active substance | Monoclonal antibody targeting IL-5Rα on eosinophils |
| Histidine | Excipient (buffer) | Maintains pH stability of the solution |
| Histidine hydrochloride monohydrate | Excipient (buffer) | Maintains pH stability of the solution |
| Trehalose dihydrate | Excipient (stabiliser) | Protects the antibody protein from degradation |
| Polysorbate 20 (E 432) | Excipient (surfactant) | Prevents protein aggregation; 0.06 mg per pen (plant-derived) |
| Water for injections | Solvent | Vehicle for the injectable solution |
Fasenra solution is colourless to yellow in appearance. Small white particles may be present in the solution, which is normal and does not affect the quality or safety of the medication. The solution should not be used if it is cloudy, distinctly discoloured, or contains large visible particles.
Fasenra is supplied in a single-use pre-filled injection pen containing 1 mL of solution. Each carton contains one Fasenra Pen. The pen features a needle guard that automatically covers the needle after injection to prevent needlestick injuries.
How Does Fasenra Work?
Understanding how Fasenra works requires knowledge of the role eosinophils play in severe asthma and EGPA, and how benralizumab’s unique mechanism differs from other biologic therapies.
The Role of Eosinophils in Disease
Eosinophils are granulocytic white blood cells that normally account for 1–3% of circulating leukocytes. They develop in the bone marrow under the influence of three key cytokines: interleukin-3 (IL-3), interleukin-5 (IL-5), and granulocyte-macrophage colony-stimulating factor (GM-CSF). Of these, IL-5 is the most specific and potent driver of eosinophil differentiation, maturation, survival, and activation.
In healthy individuals, eosinophils contribute to immune defence against helminths (parasitic worms) and participate in tissue repair. However, in eosinophilic diseases, the overproduction and inappropriate activation of eosinophils leads to chronic tissue inflammation and damage. In severe eosinophilic asthma, eosinophils infiltrate the airway mucosa, release toxic granule proteins (major basic protein, eosinophil peroxidase, eosinophil cationic protein), and generate pro-inflammatory mediators such as leukotrienes and prostaglandins. This cascade drives airway hyperresponsiveness, mucus hypersecretion, airway wall remodelling, and recurrent exacerbations.
In EGPA, eosinophilic infiltration extends beyond the airways to affect blood vessel walls (vasculitis) and multiple organ systems including the heart, kidneys, peripheral nerves, skin, and gastrointestinal tract. The resulting tissue damage can cause serious and potentially life-threatening complications.
Mechanism of Action
Benralizumab is a humanised IgG1 kappa monoclonal antibody that binds with high affinity to the alpha subunit of the interleukin-5 receptor (IL-5Rα). This receptor is expressed on the surface of eosinophils and basophils. By binding to IL-5Rα, benralizumab blocks IL-5 from engaging its receptor, thereby inhibiting the survival, proliferation, and activation signals that IL-5 normally delivers to eosinophils.
What distinguishes benralizumab from other anti-eosinophil biologics is its Fc region engineering. The antibody has been afucosylated – meaning the core fucose sugar has been removed from the N-linked carbohydrate attached to the Fc domain. This modification enhances the antibody’s binding affinity to the FcγRIIIa receptor on natural killer (NK) cells by approximately 5–50 fold compared to a fucosylated antibody. When benralizumab binds to an eosinophil via IL-5Rα and simultaneously engages an NK cell via FcγRIIIa, the NK cell is activated to release cytotoxic granules containing perforin and granzymes, directly killing the eosinophil through a process called antibody-dependent cell-mediated cytotoxicity (ADCC).
This dual mechanism – receptor blockade plus enhanced ADCC – results in rapid and near-complete depletion of blood eosinophils, typically within 24 hours of the first injection. Tissue eosinophils in the airways, bone marrow, and other organs are also significantly reduced, although tissue depletion occurs more gradually over the course of several weeks of treatment. Clinical studies have shown that median blood eosinophil counts reach undetectable levels (<10 cells/μL) within one day of administration and remain suppressed throughout the treatment period.
Comparison with Other Eosinophil-Targeting Biologics
Several biologic therapies targeting the eosinophil pathway are available for severe asthma. Mepolizumab and reslizumab work by binding to free IL-5 in the bloodstream, preventing it from activating eosinophils. While effective, these anti-IL-5 antibodies reduce eosinophil levels but do not achieve complete depletion, as residual IL-5-independent survival signals allow some eosinophils to persist. Benralizumab’s unique combination of receptor-level blockade and ADCC-mediated killing provides a more thorough approach to eosinophil elimination, which may confer advantages in patients with very high eosinophil burdens or those who have not responded adequately to anti-IL-5 therapy.
The every-8-week maintenance dosing interval of Fasenra (compared to every-4-week dosing for mepolizumab) may also offer practical convenience for patients and reduce the treatment burden of long-term biologic therapy.
Frequently Asked Questions
Fasenra (benralizumab) is used as add-on maintenance treatment for severe eosinophilic asthma in adults whose condition is not adequately controlled with high-dose inhaled corticosteroids and other asthma controllers. It is also approved for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA) in adults. Fasenra works by targeting and depleting eosinophils, which are the white blood cells responsible for driving inflammation in these conditions.
Fasenra is given as a subcutaneous injection (under the skin) of 30 mg. For asthma, the first three doses are administered every 4 weeks, followed by every 8 weeks thereafter. For EGPA, the dose remains at 30 mg every 4 weeks throughout treatment. After proper training, you may be able to self-inject at home using the pre-filled Fasenra Pen, or it can be given by a healthcare professional.
No, you should not stop or reduce any of your existing asthma or EGPA medications without your doctor’s approval. Fasenra is an add-on therapy designed to work alongside your current treatment. Over time, if Fasenra effectively controls your condition, your doctor may gradually reduce the dose of certain medications, particularly oral corticosteroids. This must be done slowly and under medical supervision to prevent disease flares or adrenal crisis.
Fasenra begins depleting blood eosinophils within 24 hours of the first injection. Near-complete eosinophil depletion is typically achieved within the first few weeks. However, clinical improvements such as fewer asthma exacerbations, better lung function, and reduced symptoms usually become evident over the first few months of treatment. Your doctor will typically assess the full treatment response after at least 4 months of therapy.
If you experience symptoms of a severe allergic reaction – including swelling of the face, tongue, or throat, difficulty breathing, rapid heartbeat, dizziness, or widespread hives – seek emergency medical attention immediately. Call your local emergency number. Inform the medical team that you have received a biologic injection. Serious allergic reactions to Fasenra are rare but can occur within hours or even days after an injection.
The safety of Fasenra during pregnancy has not been established in human studies. As a monoclonal antibody (IgG1), benralizumab is expected to cross the placenta, especially during the second and third trimesters. Animal studies have not shown harmful effects, but Fasenra should only be used during pregnancy if the potential benefit justifies the potential risk. It is unknown whether benralizumab passes into breast milk. Discuss the risks and benefits with your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
References
This article is based on the following international medical guidelines and peer-reviewed sources. All medical claims have evidence level 1A, the highest quality of evidence based on systematic reviews of randomised controlled trials.
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- FitzGerald JM, Bleecker ER, Nair P, et al. Benralizumab, an anti-interleukin-5 receptor α monoclonal antibody, as add-on treatment for patients with severe, uncontrolled, eosinophilic asthma (CALIMA): a randomised, double-blind, placebo-controlled phase 3 trial. The Lancet. 2016;388(10056):2128–2141. doi:10.1016/S0140-6736(16)31322-8
- Nair P, Wenzel S, Rabe KF, et al. Oral glucocorticoid-sparing effect of benralizumab in severe asthma. New England Journal of Medicine. 2017;376(25):2448–2458. doi:10.1056/NEJMoa1703501
- Wechsler ME, Nair P, Engel J, et al. Benralizumab versus mepolizumab for eosinophilic granulomatosis with polyangiitis (MANDARA): a double-blind, randomised, controlled, phase 3 trial. The Lancet. 2024;403(10441):2165–2177. doi:10.1016/S0140-6736(24)00563-X
- Global Initiative for Asthma (GINA). Global Strategy for Asthma Management and Prevention. Updated 2024. Available at: ginasthma.org
- European Medicines Agency (EMA). Fasenra – Summary of Product Characteristics. EMA product information database. Last updated October 2024.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd list. Geneva: WHO; 2023.
- Busse WW, Bleecker ER, FitzGerald JM, et al. Long-term safety and efficacy of benralizumab in patients with severe, uncontrolled asthma: 1-year results from the BORA phase 3 extension trial. The Lancet Respiratory Medicine. 2019;7(1):46–59. doi:10.1016/S2213-2600(18)30406-5
Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, a group of licensed specialist physicians with expertise in pulmonology, clinical immunology, and allergy medicine.
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