This study explores the safety and effects of a drug called dexpramipexole for people aged 12 and older with severe eosinophilic asthma that isn't well-controlled. **Eosinophilic asthma** is a type of asthma with high levels of eosinophils, a kind of white blood cell, in the lungs. Participants need to have had asthma for at least a year, be on certain asthma medications, and have a specific type of lung function.

• The study requires regular visits and assessments over several months.
• Participants may receive compensation for their time and effort.
• There are potential risks, including side effects from the medication.

People are not eligible if they've had recent severe asthma attacks, certain other diseases, or used specific medications recently. Women of childbearing potential must use birth control, and pregnant or breastfeeding women cannot participate. It's important to discuss with a doctor if joining this study is a good option for you.