Dupilumab

Interleukin-4 receptor alpha antagonist · also known as Dupixent

IL-4Rα monoclonal antibody; approved for CSU and other type-2 diseases, with human nasal mast-cell-count data and one idiopathic-anaphylaxis case.

How it relates to mast cells: Mast-cell-mediated condition
Types of studies cited: Randomised controlled trial , Case report
Approved in the US for: atopic dermatitis, asthma with an eosinophilic phenotype or oral corticosteroid dependence, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, COPD with an eosinophilic phenotype, chronic spontaneous urticaria, bullous pemphigoid, allergic fungal rhinosinusitis after sino-nasal surgery
Randomised trials in: chronic spontaneous urticaria, chronic rhinosinusitis with nasal polyps

What this relationship means: Given to people with a condition in which mast cells are central to the disease process, with a human mast-cell effect also measured. This is human evidence, but it is not evidence in MCAS or in a clonal mast cell disorder, and it cannot establish an MCAS outcome.

Mechanism of action

Dupilumab is a monoclonal antibody against the alpha subunit of the interleukin-4 receptor. Blocking this shared receptor inhibits signaling by interleukin-4 and interleukin-13. Those cytokines participate in type-2 inflammation and can influence IgE production and mast-cell biology, but the receptor is not unique to mast cells and dupilumab is not an anti-IgE antibody.

The most direct human mast-cell measurement comes from a randomized chronic-rhinosinusitis trial. A biomarker analysis of nasal secretions and mucosal brushings reported changes in multiple type-2 markers, urinary leukotriene E4, and nasal mucosal mast-cell counts during dupilumab exposure. That supports the adjacent mast-cell-mediated-condition tag; it does not establish a direct mast-cell-stabilizing action or an MCAS outcome.

Separate randomized trials studied chronic spontaneous urticaria, now a US-approved indication. A single case report describes dupilumab exposure in recurrent idiopathic anaphylaxis after other causes—including systemic mastocytosis and hereditary alpha-tryptasemia—were investigated. Idiopathic anaphylaxis is not the same diagnosis as MCAS, and a case report cannot determine whether the observed course was caused by the drug.

Sources

Effect of Dupilumab on Type 2 Biomarkers in Chronic Rhinosinusitis With Nasal Polyps: SINUS-52 Study Results Peer-reviewed study 2023 PMID 37322842 NCT02898454 · link checked 21 Aug 2026
Dupilumab in patients with chronic spontaneous urticaria (LIBERTY-CSU CUPID): Two randomized, double-blind, placebo-controlled, phase 3 trials Peer-reviewed study 2024 PMID 38431226 NCT04180488 · link checked 21 Aug 2026
Dupilumab in Patients With Chronic Spontaneous Urticaria: Phase 3 LIBERTY-CSU CUPID Randomized Clinical Trials Peer-reviewed study 2026 PMID 41706458 NCT04180488 · link checked 21 Aug 2026
Treatment of idiopathic anaphylaxis with dupilumab: a case report Peer-reviewed study 2023 PMID 37689672 · link checked 21 Aug 2026
Dupixent (dupilumab) US prescribing information Drug label · link checked 21 Aug 2026

What this evidence cannot establish

The mast-cell-count analysis came from nasal mucosal brushings in chronic rhinosinusitis with nasal polyps, not from people with MCAS, and cannot show that dupilumab directly stabilizes mast cells. The idiopathic-anaphylaxis publication describes one patient and has no comparison group. In the CSU programme, Study B did not meet its primary endpoint; the current US indication is based on Studies A and C and is limited to chronic spontaneous urticaria. Current labeling also warns about hypersensitivity reactions, ocular surface inflammation, eosinophilic conditions, and use around vaccination or helminth infection.

What this page does not say

No dosing, and no claim that this works. The entry describes a published mechanism, the cited study types, and what those studies cannot establish — nothing further. Why the site is built this way.

Recently verified. Verified 21 Aug 2026