AstraZeneca’s severe asthma drug Tezspire has been granted market authorization in South Korea

The Ministry of Food and Drug Safety (MFDS) in South Korea approved Tezspire on Thursday, granting AstraZeneca Korea market authorization for the drug. Tezspire was previously approved by the United States Food and Drug Administration (FDA) on December 17, 2021, for the treatment of severe asthma.

Tezspire is a novel treatment for severe asthma in adults and adolescents over 12 years old. The approved indications for Tezspire are for patients aged 12 and older who have severe asthma that is not adequately controlled with standard maintenance treatments, such as high-dose inhaled corticosteroids and other asthma medications.

New TSLP Blocker for Asthma Control

Tezspire is a thymic stromal lymphopoietin (TSLP) blocker, a human monoclonal antibody IgG2λ, which can bind to TSLP and effectively reduce TSLP-induced inflammatory responses. This mechanism not only significantly reduces the frequency of asthma attacks but also improves patient breathing and lung function, enhancing control over asthma symptoms.

Asthma Mainly Arises from Inflammation and Hypersensitivity of the Airways

The common cause of asthma is the stimulation of the epithelial cell layer by various external irritants, such as viruses, allergens, pollutants/smoke, bacteria, and other external stimuli, which promote the release of TSLP and induce inflammation.

Clinically, asthma has 2 main characteristics: airway inflammation or hyperresponsiveness. Airway inflammation is related to various cytokines and different types of immune responses, mainly divided into 3 situations: firstly, allergic inflammation caused by IL-4 accompanied by increased levels of IgE. Secondly, allergic and eosinophilic inflammation caused by IL-4, IL-5, and IL-13, characterized by elevated levels of IgE, fractional exhaled nitric oxide (FeNO), and eosinophils. Finally, eosinophilic inflammation is caused solely by IL-5, mainly characterized by the accumulation of eosinophils.

Another key feature of asthma: airway hypersensitivity, highlights the role of mast cells in the immune system, which can initiate and enhance inflammatory responses by releasing histamine and other mediators.

Finally, it is worth noting that Tezspire does not specify a particular phenotype (such as eosinophilic or allergic) or biomarker restrictions in its approved label, making it flexible and offering a more comprehensive treatment option for patients with severe asthma.

Author

Oscar Wu