Tezepelumab for the treatment of severe asthma: a plain language summary of the PATHWAY and NAVIGATOR studies

This is a summary of the results of 2 clinical studies that looked at a medicine called tezepelumab. Tezepelumab is approved in the United States of America (USA), the European Union (EU) and several other countries for the treatment of severe, uncontrolled asthma in people aged 12 and above. The results of these 2 studies, called PATHWAY and NAVIGATOR, formed the basis for tezepelumab's approval for use. Tezepelumab is a type of biologic treatment called an antibody. Biologics are treatments that target certain cells or proteins in the body and often in the immune system - the body's natural defence system against infections and diseases - to reduce patients' disease. It works by blocking a key first step in the body's chain reaction leading to inflammation in the airways of people with severe asthma. The clinical studies were done to learn if tezepelumab can be used to treat people with severe, uncontrolled asthma and to find out about its safety. In both studies, tezepelumab was compared to placebo. A placebo is a dummy treatment that looked like tezepelumab but did not have any medicine in it.

In both studies, tezepelumab reduced the number of severe asthma attacks that the participants had per year compared with placebo. It also increased the volume of air that the participants could breathe out in 1 second compared with placebo. Tezepelumab was well-tolerated, and a similar number of participants had health issues in the tezepelumab and placebo treatment groups. The most common health issues that the participants had during the PATHWAY study were: Worsening of asthma, common cold, headache, and inflammation of the airways. The most common health issues that the participants had during the NAVIGATOR study were: Common cold, infection of the sinuses, throat and airways, headache, worsening of asthma, and inflammation of the airways.

The results showed that participants who had monthly doses of tezepelumab had fewer severe asthma attacks and better lung function than those who had placebo. In both studies, the health issues that the participants had were similar between the tezepelumab and placebo treatment groups. Overall, the studies showed that tezepelumab worked in a broad population of people with severe asthma and that the study participants had an acceptable level of health issues during the studies. These results led to the approval of tezepelumab for people with severe asthma aged 12 and above in the USA, EU and other countries. Clinical Trial Registration: PATHWAY study: NCT02054130; NAVIGATOR study: NCT03347279 (ClinicalTrials.gov).