Xolair vs Nucala
Anti-IgE against anti-IL-5 in severe asthma — the blood test that decides which one a patient is likely to respond to.
At a glance
Key differences
- Different classes. Xolair is an anti-IgE antibody; Nucala is an IL-5 antagonist. They act on different targets in the body.
- How they are taken. Both are given by the subcutaneous route.
- Time on the market. Xolair was first approved by the FDA in 2003, Nucala in 2015. That gives Xolair roughly 12 more years of real-world use and long-term safety data.
- Who markets them. Xolair is marketed by Genentech (Roche); Nucala by GlaxoSmithKline.
What each one treats
XOLAIR is an anti-IgE antibody indicated for: Moderate to severe persistent asthma in adults and pediatric patients 6 years of age and older with a positive skin test or in vitro reactivity to a perennial aeroallergen and symptoms that are inadequately controlled with inhaled corticosteroids ( 1.1 ) Chronic rhinosinusitis with nasal polyps (CRSwNP) in adult patients 18 years of age and older with inadequate response to nasal corticosteroids, as add-on maintenance treatment ( 1.2 ) IgE-mediated food allergy in adult and pediatric patients aged 1 year and older for the reduction of allergic reactions (Type I), including anaphylaxis, that may occur with accidental exposure to one or more foods. To be used in conjunction with food allergen avoidance ( 1.3 ) Chronic spontaneous urticaria (CSU) in adults and adolescents 12 years of age and older who remain symptomatic despite H1 antihistamine…
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 Asthma, Chronic Rhinosinusitis with Nasal Polyps, and IgE-Mediated Food Allergy Omalizumab inhibits the binding of IgE to the high-affinity IgE receptor (FcεRI) on the surface of mast cells, basophils, and dendritic cells, resulting in FcεRI down-regulation on these cells. In allergic asthmatics, treatment with omalizumab inhibits IgE-mediated inflammation, as evidenced by reduced blood and tissue eosinophils and reduced inflammatory mediators, including IL-4, IL-5, and IL-13. Chronic Spontaneous Urticaria Omalizumab binds to IgE and lowers free IgE levels. Subsequently, IgE receptors (FcεRI) on cells down-regulate. The mechanism by which these effects of omalizumab…
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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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.