Observational, retrospective study in adults (≥18 years) with severe asthma (maintenance treatment with high dose inhaled corticosteroids combined with long-acting agonist β2) and eosinophilic phenotype, who at the discretion of the investigator were candidates to receive benralizumab in the individualized access program approved by national health authorities.

Primary Objective: To describe the demographic and baseline characteristics in patients with severe eosinophilic asthma who participated in the individualized access program approved in Spain and received at least one dose of benralizumab.

Secondary Objectives: To describe clinical outcomes in severe eosinophilic asthma patients who received at least three doses of benralizumab in the individualized access program.

Inclusion Criteria:

• Adult patients (age ≥18 years)
• Diagnosis of severe eosinophilic asthma requiring stable treatment of high doses of inhaled corticosteroids and a long-acting agonist β2 ± additional asthma controller
• Received at least one dose of benralizumab during the individualized access program period (March-December of 2018)
• Informed consent signed

Exclusion Criteria:

• Patients enrolled in a clinical trial who received benralizumab during the same period of the individualized access program
• Refuse to sign the informed consent

The study population will be all patients who received at least one dose of benralizumab in individualized access program approved by the AEMPS.