Fasenra vs Nucala
Both are IL-5 inhibitors. Here is how Fasenra and Nucala compare on class, mechanism, dosing, approval and supply.
At a glance
Key differences
- Same class. Both Fasenra and Nucala are IL-5 inhibitors, so they work through the same broad mechanism. Differences between them tend to be about dosing, route, how selective they are, and side effects rather than what they target.
- How they are taken. Both are given by the subcutaneous route.
- Time on the market. Fasenra was first approved by the FDA in 2017, Nucala in 2015. That gives Nucala roughly 2 more years of real-world use and long-term safety data.
- Who markets them. Fasenra is marketed by AstraZeneca; Nucala by GlaxoSmithKline.
What each one treats
FASENRA is an interleukin-5 receptor alpha-directed cytolytic monoclonal antibody (IgG1, kappa) indicated for: • add-on maintenance treatment of adult and pediatric patients aged 6 years and older with severe asthma, and with an eosinophilic phenotype. ( 1.1 ) • treatment of adult patients with eosinophilic granulomatosis with polyangiitis (EGPA). ( 1.2 ) • treatment of adult and pediatric patients aged 12 years and older with hypereosinophilic syndrome (HES) without an identifiable non-hematologic secondary cause. ( 1.3 ) Limitations of Use : Not for relief of acute bronchospasm or status asthmaticus. (1.1) 1.1 Asthma FASENRA is indicated for the add-on maintenance treatment of adult and pediatric patients aged 6 years and older with severe asthma, and with an eosinophilic phenotype. Limitations of Use: • FASENRA is not indicated for the relief of acute bronchospasm or status asthmatic…
NUCALA is an interleukin-5 (IL-5) antagonist monoclonal antibody (IgG1 kappa) indicated for: • Add-on maintenance treatment of adult and pediatric patients aged 6 years and older with severe asthma and with an eosinophilic phenotype. ( 1.1 ) • Add-on maintenance treatment of adult patients aged 18 years and older with chronic rhinosinusitis with nasal polyps (CRSwNP). ( 1.2 ) • Add-on maintenance treatment of adult patients with inadequately controlled chronic obstructive pulmonary disease (COPD) and an eosinophilic phenotype. ( 1.3 ) • The treatment of adult patients with eosinophilic granulomatosis with polyangiitis (EGPA). ( 1.4 ) • The treatment of adult and pediatric patients aged 12 years and older with hypereosinophilic syndrome (HES) for greater than or equal to 6 months without an identifiable non-hematologic secondary cause. ( 1.5 ) Limitations of use: Not for relief of acute …
How each one works
12.1 Mechanism of Action Benralizumab is a humanized afucosylated, monoclonal antibody (IgG1, kappa) that directly binds to the alpha subunit of the human interleukin-5 receptor (IL-5Rα) with a dissociation constant of 11 pM. The IL-5 receptor is expressed on the surface of eosinophils and basophils. In an in vitro setting, the absence of fucose in the Fc domain of benralizumab facilitates binding (45.5 nM) to FcɣRIII receptors on immune effector cells, such as natural killer (NK) cells, leading to apoptosis of eosinophils and basophils through antibody-dependent cell-mediated cytotoxicity (ADCC). Inflammation is an important component in the pathogenesis of asthma, EGPA, and HES. Multiple …
12.1 Mechanism of Action Mepolizumab is an IL-5 antagonist (IgG1 kappa). IL-5 is the major cytokine responsible for the growth and differentiation, recruitment, activation, and survival of eosinophils. Mepolizumab binds to IL-5 with a dissociation constant of 100 pM, inhibiting the bioactivity of IL-5 by blocking its binding to the alpha chain of the IL-5 receptor complex expressed on the eosinophil cell surface. Inflammation is an important component in the pathogenesis of asthma, CRSwNP, COPD, EGPA, and HES. Multiple cell types (e.g., mast cells, eosinophils, neutrophils, macrophages, lymphocytes) and mediators (e.g., histamine, eicosanoids, leukotrienes, cytokines) are involved in inflam…
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Which medicine is right for a given person depends on their diagnosis, other conditions, other medicines, kidney and liver function, pregnancy, and cost or reimbursement — none of which this page knows. Two drugs in the same class are not automatically interchangeable. Never start, stop or switch a prescription medicine on the basis of a web page; that decision belongs to you and your clinician or pharmacist.
How this page is built
The facts on this page are pulled directly from official U.S. FDA datasets — they are not written from memory. Each field below names the dataset it came from, so you can check it yourself.
- FDA Drug Label (openFDA) ↗ Indications, mechanism of action and pharmacologic class
- Drugs@FDA ↗ First FDA approval date and the company holding the application
- FDA Drug Shortage Database ↗ Current US supply / shortage status
Plain-English summaries and drug-class explainers are written and reviewed by Sreepriya Prasannan (MSc Digital Transformation of Life Sciences (Innopharma Education / Griffith College); MSc & BSc Botany). Data is retrieved automatically from the sources above and cross-checked with AI-assisted verification (Anthropic's Claude) — brand and generic names are matched against the exact FDA product record so that a combination product or a different formulation cannot be mistaken for the drug on this page. An editor reviews the result before publication. We describe this in full in our editorial standards and corrections policy. The FDA data on this page was last retrieved on 5 Oct 2026. How every register is built: methodology · fixes we have made: corrections log.