Tezepelumab for Severe Asthma: One Drug Targeting Multiple Disease Pathways and Patient Types

Abstract: Asthma is a heterogeneous inflammatory disease of the airways, affecting many children, adolescents, and adults worldwide. Up to 10% of people with asthma have severe disease, associated with a higher risk of hospitalizations, greater healthcare costs, and poorer outcomes. Patients with severe asthma generally require high-dose inhaled corticosteroids and additional controller medications to achieve disease control; however, many patients remain uncontrolled despite this intensive treatment. The treatment of severe uncontrolled asthma has improved with greater understanding of asthma pathways and phenotypes as well as the advent of targeted biologic therapies. Tezepelumab, a monoclonal antibody, blocks thymic stromal lymphopoietin, an epithelial cytokine that has multifaceted effects on the initiation and persistence of asthma inflammation and pathophysiology. Unlike other biologic treatments, tezepelumab has demonstrated efficacy across severe asthma phenotypes, with the magnitude of effects varying by phenotype. Here we describe the anti-inflammatory effects and efficacy of tezepelumab across the most relevant phenotypes of severe asthma. Across clinical studies, tezepelumab reduced annualized asthma exacerbation rates versus placebo by 63– 71% in eosinophilic severe asthma, by 58– 68% in allergic severe asthma, by 67– 71% in allergic and eosinophilic severe asthma, by 34– 49% in type 2-low asthma, and by 31– 41% in oral corticosteroid-dependent asthma. Furthermore, in all these asthma phenotypes, tezepelumab demonstrated higher efficacy in reducing exacerbations requiring hospitalizations or emergency department visits versus placebo. In patients with severe uncontrolled asthma, who commonly have multiple drivers of inflammation and disease, tezepelumab may modulate airway inflammation more extensively, as other available biologics block only specific downstream components of the inflammatory cascade.

Plain Language Summary: Asthma is characterized by an immune response leading to airway inflammation. People with severe asthma may react to different triggers and develop different types of airway inflammation. In patients with asthma, a protein called thymic stromal lymphopoietin (TSLP) plays an important role in the immune response that leads to the signs and symptoms of asthma. TSLP is released by the airway lining in response to different asthma triggers, driving an immune chain reaction, leading to airway narrowing and tightening, increased airway inflammation, worsening asthma symptoms, and asthma attack. Tezepelumab is a monoclonal antibody (a type of protein) that prevents TSLP from attaching to its receptor, thereby blocking its activity, reducing airway inflammation and asthma symptoms. Tezepelumab is an add-on medicine for the treatment of people aged 12 years or older with severe asthma that is not controlled with their current medicines.
In this article, we discuss how tezepelumab may work in different types of asthma, for example allergic asthma, eosinophilic asthma, and T2-low asthma. We also describe how effective tezepelumab is in these different asthma types, through the reduction of asthma attacks and improvement in lung function, symptom control, and quality of life, leading to fewer emergency department visits and hospitalizations for asthma.

Keywords: exacerbations, eosinophilic, allergic, type 2, oral corticosteroid-dependent, airway hyperresponsiveness