Last reviewed 2026-05-22 · How we verify

Nucala (MEPOLIZUMAB)

Nucala (generic name: MEPOLIZUMAB) is a Interleukin-5 Antagonist [EPC] Monoclonal antibody drug developed by GSK. It is currently FDA-approved (first approved 2015) for Allergic granulomatosis angiitis, Asthma, Eosinophilic asthma.

Nucala works by binding to interleukin-5, a protein that stimulates the production of eosinophils.

Nucala is a monoclonal antibody that inhibits interleukin-5, classified as an inhibitor. It is used to treat conditions such as asthma, chronic rhinosinusitis with nasal polyps, and granulomatosis with polyangiitis, among others.

At a glance

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 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, 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 inflammation. Mepolizumab, by inhibiting IL-5 signaling, reduces the production and survival of eosinophils; however, the mechanism of mepolizumab action in asthma, CRSwNP, EGPA, and HES has not been definitively established.

Approved indications

• Allergic granulomatosis angiitis
• Asthma
• Eosinophilic asthma

Common side effects

• Headache
• Injection site reaction
• Back pain
• Fatigue
• Influenza
• Urinary tract infection
• Abdominal pain upper
• Pruritus
• Eczema
• Muscle spasms
• Herpes zoster
• Allergic rhinitis

Key clinical trials

• Efficacy and Safety Study of Mepolizumab Adjunctive Therapy in Subjects With Severe Uncontrolled Refractory Asthma (PHASE3)
• Efficacy and Safety Study of Mepolizumab in Subjects With Severe Hypereosinophilic Syndrome (HES) (PHASE3)
• A Study to Investigate Mepolizumab in the Treatment of Eosinophilic Granulomatosis With Polyangiitis (PHASE3)
• Mepolizumab Steroid-Sparing Study in Subjects With Severe Refractory Asthma (PHASE3)
• Dose Ranging Efficacy And Safety With Mepolizumab in Severe Asthma (PHASE2)
• Aggravated Airway Inflammation: Research on Biological Treatment (Mepolizumab) (PHASE4)
• Changes in Gene Transcription and Immunophenotypes Following Mepolizumab Treatment for Asthma
• NUCALA® Special Drug Use Investigation (EGPA, Long-term)

Patents

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Nucala CI brief — competitive landscape report
• Nucala updates RSS · CI watch RSS
• GSK portfolio CI

Frequently asked questions about Nucala

Related

• Drug class: All Interleukin-5 Antagonist [EPC] drugs
• Target: All drugs targeting Interleukin-5
• Manufacturer: GSK — full pipeline
• Therapeutic area: All drugs in Respiratory
• Indication: Drugs for Allergic granulomatosis angiitis
• Indication: Drugs for Asthma
• Indication: Drugs for Eosinophilic asthma

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing