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Generic name: benralizumab systemic

Brand names: Fasenra

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Auto-injector, Subcutaneous [preservative free]:

Fasenra Pen: 30 mg/mL (1 mL)

Solution Prefilled Syringe, Subcutaneous [preservative free]:

Fasenra: 30 mg/mL (1 mL)


Mechanism of Action

Benralizumab, a humanized afucosylated, monoclonal antibody (IgG1, kappa) that binds to the alpha subunit of the interleukin-5 receptor. IL-5 is the major cytokine responsible for the growth and differentiation, recruitment, activation, and survival of eosinophils (a cell type associated with inflammation and an important component in the pathogenesis of asthma). Benralizumab, by inhibiting IL-5 signaling, reduces the production and survival of eosinophils and basophils through antibody dependent cell-mediated cytotoxicity; however, the mechanism of benralizumab action in asthma has not been definitively established.



3.1 L (central); 2.5 L (peripheral)


Undergoes proteolytic degradation via enzymes that are widely distributed in the body and not restricted to hepatic tissue.



Half-Life Elimination

~15.5 days

Use: Labeled Indications

Asthma, severe: Add-on maintenance treatment of severe asthma in adults and children ≥12 years of age with an eosinophilic phenotype

Limitations of use: Not indicated for treatment of other eosinophilic conditions or for the relief of acute bronchospasm or status asthmaticus


Hypersensitivity to benralizumab or any component of the formulation

Dosage and Administration

Dosing: Adult

Asthma, severe: SubQ: 30 mg every 4 weeks for the first 3 doses, and then once every 8 weeks.

Note: Use of benralizumab had an oral glucocorticoid-sparing effect in patients relying on oral glucocorticoids to manage severe asthma associated with eosinophilia (Nair 2017).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Asthma, eosinophilic phenotype; add-on maintenance therapy: Children ≥12 years and Adolescents: SubQ: 30 mg every 4 weeks for the first 3 doses then once every 8 weeks


Solution is clear to opalescent, colorless to slight yellow liquid; particles may be present in the solution that appear translucent or white to off-white; do not use if cloudy or discolored. Syringe may contain a small air bubble; do not expel the air bubble prior to administration. Refer to manufacturer's labeling for additional information.


SubQ: Prior to administration, allow syringe/autoinjector to warm at room temperature for ~30 minutes. Administer SubQ into the upper arm, thigh, or abdomen. Prefilled syringe should only be administered by a health care provider; autoinjector may be administered by patient or caregiver after proper training. Refer to the manufacturer's labeling for additional administration instructions.


Store in original carton at 2°C to 8°C (36°F to 46°F). Do not freeze or shake. Protect from light. May be stored at room temperature (≤25°C [77°F]) in original carton for ≤14 days.

Drug Interactions

There are no known significant interactions.

Adverse Reactions

>10%: Immunologic: Antibody development (13%; neutralizing: 12%)

1% to 10%:

Central nervous system: Headache (8%)

Respiratory: Pharyngitis (5%)

Miscellaneous: Fever (3%)

Postmarketing: Anaphylaxis, angioedema, hypersensitivity reaction


Concerns related to adverse effects:

  • Hypersensitivity: Hypersensitivity reactions (eg, anaphylaxis, angioedema, urticaria, rash) may occur, typically within hours of administration. Delayed hypersensitivity reactions, occurring days after administration, have also been reported. Discontinue use in patients who experience a hypersensitivity reaction.

Disease-related concerns:

  • Asthma: Not indicated for the treatment of acute asthma symptoms (eg, acute bronchospasm) or acute exacerbations, including status asthmaticus. Appropriate rescue medication should be available. Patients who experience continued uncontrolled asthma or worsening of symptoms following treatment initiation with benralizumab should seek medical attention.
  • Helminth infections: It is unknown if administration of benralizumab will influence a patient's immune response against parasitic infections. Therefore, patients with preexisting helminth infections should undergo treatment of the infection prior to initiation of benralizumab therapy. Patients who become infected during benralizumab treatment and do not respond to antihelminth therapy should discontinue benralizumab until the infection resolves.

Other warnings/precautions:

  • Corticosteroids: Do not discontinue systemic or inhaled corticosteroids abruptly upon initiation of benralizumab. Reductions in corticosteroid dose should be gradual, if appropriate. Clinicians should note that a reduction in corticosteroid dose may be associated with withdrawal symptoms and/or unmask conditions previously suppressed by systemic corticosteroid therapy.

Monitoring Parameters

Anaphylaxis/hypersensitivity reactions (during and after administration); peak flow, and/or other pulmonary function tests; monitor for signs of infection


Pregnancy Considerations

IgG monoclonal antibodies, including benralizumab, are expected to cross the placenta with higher concentrations in the third trimester.

Uncontrolled asthma is associated with adverse events on pregnancy (increased risk of preeclampsia, preterm birth, low birth weight infants). Asthma should be closely monitored in pregnant women.

Data collection to monitor pregnancy and infant outcomes following exposure to benralizumab is ongoing. Healthcare providers are encouraged to enroll exposed pregnant females in the MotherToBaby Pregnancy Studies conducted by the Organization of Teratology Information Specialists (OTIS) (877-311-8972 or Patients may also enroll themselves.

Patient Education

What is this drug used for?

  • It is used to treat asthma.
  • Do not use this drug to treat an asthma attack. Use a rescue inhaler. Talk with your doctor.

Frequently reported side effects of this drug

  • Headache
  • Sore throat

Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:

  • Dizziness
  • Passing out
  • Difficulty breathing
  • Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated January 17, 2020.