Individuals with asthma live with constant airway inflammation. Certain environmental triggers, exercise or illness can cause even more swelling and constriction of the muscles around the airway, making it difficult to breath.
It is estimated that approximately half of severe asthmatics, as many as 650,000 – 1,300,000 patients, are unable to control their condition with standard therapies.
Asthma has two predominant subtypes categorized by the degree of inflammation present in the airways caused by a type of immune cell called Th2 cells. Individuals with high levels of Th2 associated inflammation have the Th2-high subtype. Th2-high asthma is often accompanied by high levels of eosinophils and production of immunoglobulin E (IgE). Individuals with Th2-high asthma may respond to treatment with steroids and recently approved biologic therapies which target IgE or Th2-cytokines.
Individuals with the Th2-low subtype of asthma have low levels of Th2-associated inflammation in their airways. A portion of Th2-low individuals have airway inflammation caused by Th17 cytokines such as IL-17. Individuals with Th2-low asthma typically have low levels of eosinophils. Their disease is often more severe and they may not respond to treatment with corticosteroids or recently approved biologic therapies.
Itolizumab is designed to block the activation and trafficking of pathogenic T cells and has the potential to treat both Th2-high and Th2-low asthma. Equillium is currently evaluating itolizumab in a clinical trial in individuals with moderate to severe asthma that is uncontrolled with other medications.