BACKGROUND: Many patients with asthma experience loss of lung function over time, and in certain patients this can lead to progressive obstructive patterns similar to COPD. Patients with severe asthma may experience accelerated lung function decline (LFD). However, characteristics and risk factors for LFD in asthma have not been well described. Dupilumab may prevent or slow the rate of LFD in patients with uncontrolled, moderate-to-severe asthma. ATLAS trial is designed to evaluate the role of dupilumab in preventing/slowing LFD over a period of 3 years versus standard-of-care therapy. METHODS: ATLAS (clinicaltrials.gov identifier NCT05097287) is a randomised, double-blind, placebo-controlled, multicentre study that will include adult patients with uncontrolled moderate-to-severe asthma.