Tezspire (tezepelumab), an anti-TSLP therapy for the treatment of severe asthma, is entering the market with its effectiveness regardless of biomarker status.

Although the drug still faces reimbursement hurdle, clinical practices have high hopes. They expect that Tezspire's versatility can change the current treatment paradigm in which drugs are preferentially prescribed to patients with severe asthma.

During a February 18 press conference hosted by AstraZeneca Korea to celebrate the launch of Tezspire, Dr. Heung-Woo Park, Professor of the Institute of Allergy and Clinical Immunology at Seoul National University Hospital, anticipated that unmet needs for asthma treatment would be resolved.

Tezspire is the first and only drug to treat severe asthma by inhibiting 'thymic stromal lymphopoietin (TSLP).'

By inhibiting TSLP, which is one of the factors associated with the pathology of asthma, the drug shows effectiveness in modulating symptoms in a wide range of patients with severe asthma regardless of asthma subtype.

In December 2023, Tezspire was approved by the Ministry of Food and Drug Safety (MFDS) as an "Add-on maintenance treatment in adults and adolescents 12 years and older with severe asthma not adequately controlled by previous treatments." AstraZeneca plans to launch Tezspire in the first half of the year.

The industry closely watches Tezspire for overcoming biomarker limitations and expanding treatment opportunities for patients with severe asthma.

One of the difficulties in diagnosing asthma and its treatments is the wide range of manifestations of the disease.

An accurate diagnosis is difficult because a clear biomarker for each asthma subtype is lacking. In other words, this causes a significant challenge in establishing a customized treatment strategy. Treatment options for non-Type-2 inflammation are still limited.

Dr. Park said, "The introduction of biological agents improved the prognosis of patients with severe asthma, but unmet needs are yet to be addressed." Adding, "Severe asthma is a disease that causes not only decreased individual patient's quality of life but a societal burden. We are desperately in need of more effective treatment alternatives."

The industry analysis suggests that Tezspire's unique mechanism of inhibiting TSLP, which drives asthma inflammatory cascade responses, will likely give distinction.

Based on Phase 2 PATHWAY study and Phase 3 NAVIGATOR study, Tezspire was effective in demonstrating clinically significant improvement in asthma exacerbation rate regardless of asthma subtypes or biomarker status.

Dr. Hwa Young Lee, Professor of Seoul St. Mary's Hospital, said, "This drug has brought a paradigm shift to the treatment of a wide range of patients with severe asthma since it can be used regardless of biomarker status, such as treating patients with low blood eosinophil or fractional exhaled nitric oxide (FeNO).

Dr. Lee said, "It has shown effectiveness in reducing asthma exacerbation regardless of weather or accompanying diseases. Therefore, it is expected to expand treatment opportunities for patients with severe asthma significantly."

Tezspire targets the standard therapy of severe asthma…"We will consider priority treatment"

However, the indication of Tezspire is limited to cases where patients are not responding to previous treatments. It also has a limitation of not reimbursement by the National Health Insurance.

Tezspire can be used regardless of type-2 inflammation and non-type-2 inflammation. It was expected that the use of the drug in clinical practices will gradually increase for patients with severe asthma whose biomarker status is difficult to identify.

Dr. Park stated, "The drug can be expanded for use in both type-2 inflammation and non-type-2 inflammation. Clinicians may choose to use a treatment effective for a wider range of conditions first, and then select a treatment with a narrower range."

Dr. Lee also emphasized that "For pneumonia treatment, doctors may use broader-spectrum antibiotics when identifying bacteria is difficult. In severe asthma, Tezspire can be effectively used if diagnosing type-2 inflammation proves difficult."

However, due to limitations in reimbursement, only 10-20% of severe asthma patients are likely to receive the treatment readily. Ultimately, it will be up to the company to make efforts to obtain reimbursement.

Regarding this, Ji-Young Kim, executive director of AstraZeneca Korea's Respiratory·Inflammatory Division, stated, "We acknowledge that severe asthma poses an economic burden." Kim added, "We are carefully considering patient support programs to reduce patient's economic burden."