A Study to Assess the Effect of Dexpramipexole in Adolescents and Adults With Eosinophilic Asthma

Inclusion criteria

• ✓. Signed informed consent form and assent form, as appropriate.
• ✓. Male or female ≥12 years of age at Screening Visit 1. Sites in Poland will only include participants aged ≥18 years.
• ✓. Documented physician diagnosis of asthma for ≥12 months prior to Screening Visit 1.
• ✓. Participants requiring at a minimum daily low dose inhaled corticosteroids (ICS; ≥100 μg/day fluticasone propionate dry powder formulation daily or clinically comparable, per GINA 2021), plus one or more additional daily maintenance asthma controller medications, eg, long-acting β2 agonist (LABA), leukotriene antagonist, theophylline, long-acting muscarinic antagonists, cromolyn/nedocromil. Note: In Poland, this will instead include participants requiring a minimum daily medium dose ICS (≥500 μg/day fluticasone propionate dry powder formulation daily or clinically comparable, per GINA 2021). Use of daily ICS must be for at least 12 weeks prior to Screening Visit 1 and the doses of all controller medications must be stable for at least 4 weeks prior to Screening Visit 1.
• ✓. Pre-BD FEV1 ≥40% and \<80% (\<90% for participants 12 to 17 years of age) of predicted at Screening Visit 2.
• ✓. Bronchodilator reversibility, at Screening Visit 2, as evidenced by ≥12% and ≥200 mL improvement in FEV1, 15 to 30 minutes following inhalation of 400 μg (four puffs) of albuterol/salbutamol (≥12% and ≥160 mL for ages 12 to 17).Participants who do not meet the bronchodilator reversibility inclusion criterion but have ≥10% and ≥160 mL reversibility, may repeat the reversibility spirometry assessment once during the Screening Period, at an unscheduled visit at least 7 days prior to baseline.
• ✓. ACQ-6 ≥1.5 at Screening Visit 2.
• ✓. Eosinophil count of ≥0.30x10⁹/L at Screening Visit 1. If the initial value is between 0.250x10⁹/L to 0.299x10⁹/L, then this may be repeated once at an unscheduled visit (prior to Screening Visit 2).