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Nucala HES
Nucala HES

NUCALA is indicated for the treatment of adult and pediatric patients aged 12 years and older with hypereosinophilic syndrome (HES) for ≥6 months without an identifiable non-hematologic secondary cause.


NUCALA provides proven protection from flares1

Randomized, placebo-controlled trial


Primary endpoint results: Proportion of patients who experienced HES flare(s)* during the 32-week study or withdrew. NUCALA 28% vs placebo 56%, P=0.002.

HES flare: Worsening of clinical signs/symptoms or increased eosinophils (on ≥2 occasions), resulting in an escalation/addition of oral corticosteroids (OCS) or cytotoxic or immunosuppressive therapy.

Identifying HES

Identifying HES

The definition, clinical manifestations, and more

Learn about HES

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Flare reduction

Proportion of patients with flares and time to first flare

Review the data

Eosinophil reduction icon

Mechanism of action (MOA) and eosinophil reduction

See the results of NUCALA on eosinophil reduction

View MOA and eosinophil data

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Access & reimbursement

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Request a Rep

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Register for updates


  1. Roufosse F, Kahn JE, Rothenberg ME, et al. Efficacy and safety of mepolizumab in hypereosinophilic syndrome: A phase III, randomized, placebo-controlled trial. J Allergy Clin Immunol. 2020;146(6):1397-1405.