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Medically reviewed by Last updated on Jul 29, 2019.


(ben ra LIZ ue mab)

Dosage Forms

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

Solution Prefilled Syringe, Subcutaneous [preservative free]:

Fasenra: 30 mg/mL (1 mL)

Brand Names: U.S.

  • Fasenra

Pharmacologic Category

  • Interleukin-5 Receptor Antagonist
  • Monoclonal Antibody, Anti-Asthmatic


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.


3.2 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 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

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


Prior to administration, remove prefilled syringe from refrigerator and allow to warm at room temperature for about 30 minutes. 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.


SubQ: Administer SubQ into the upper arm, thigh, or abdomen.


Store in original carton at 2°C to 8°C (36°F to 46°F). Do not freeze or shake. Protect from light. Use within 24 hours after removal from refrigerator.

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%)

Frequency not defined: Hypersensitivity: 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

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache or pharyngitis. Have patient report immediately to prescriber dizziness, passing out, or difficulty breathing (HCAHPS).

• Educate patient about signs of a significant reaction (eg, 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. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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