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What is Fasenra used for and how does it work?

Medically reviewed by Carmen Pope, BPharm. Last updated on Oct 4, 2024.

Official answer

by Drugs.com

Fasenra injection may be used to treat severe eosinophilic asthma in adults and children aged 6 years and older or eosinophilic granulomatosis with polyangiitis (EGPA) in adults.

Fasenra's mechanism of action (MOA) involves specifically targeting eosinophils, which are white blood cells associated with inflammation found in the airways of people with asthma and tissues of people with EGPA. Fasenra binds to interleukin receptor (IL-5Ra) found on the surface of eosinophils which blocks the effects of interleukin 5, a cytokine that is crucial for eosinophil development. Cytokines are small secreted proteins that are involved in cell signaling and interactions. By binding to IL-5, Fasenra reduces the production and survival of eosinophils, reducing the number of eosinophils in tissues and the blood. Eosinophils play a key role in inflammation and certain conditions such as asthma, EGPA, cancer, and parasitic infections..

Fasenra also binds to and activates another receptor called FcγRIIIa found on natural killer (NK) cells (also a type of white blood cell). This enhances the programmed cell death of eosinophils via a process called antibody-dependent cell-mediated cytotoxicity (ADCC). It also enhances the apoptosis of basophils. Basophils are yet another type of white blood cell that also play a role in the airway inflammation associated with asthma.

Fasenra may also be called a biologic. Fasenra belongs to the drug class Interleukin inhibitors.

Related questions

Fasenra mechanism of action summary

Fasenra is a monoclonal antibody that has a targeted approach. Fasenra works by:

  • Depleting the number of eosinophils
  • Blocking IL-5 from binding to eosinophils, which prevents IL-5 from helping eosinophils to multiply and survive
  • Enhancing the ability of natural killer (NK) cells to kill eosinophils
  • Enhancing the ability of NK cells to kill basophils, which also play a role in the airway-inflammation associated with asthma and tissue inflammation in EGPA.

References

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