4-Week Maintenance ICS-Formoterol versus ICS in Adults Newly Diagnosed Mild Asthma: Effects on Symptoms, Lung Function, and Inflammation.

Purpose of review: This study aimed to determine whether patients with newly diagnosed mild asthma benefit more from initiating treatment with maintenance inhaled corticosteroids (ICS) plus formoterol versus ICS alone. We compared the effects of these two 4-week maintenance strategies on asthma control, lung function, and airway inflammation.

Recent findings: Recent evidence supports the effectiveness of as-needed ICS-formoterol in mild asthma management. However, data on initial short-term maintenance strategies remain limited. Most studies focus on long-term outcomes or symptom-driven therapy, with little insight into the early phase and its impact on inflammation and lung function. Notably, GINA 2024 emphasizes that "mild asthma" is a retrospective label and may not reliably guide the selection of the appropriate initial treatment step. Even in so-called mild asthma, severe outcomes may occur, highlighting the need for early, objective assessment to guide treatment decisions. In this retrospective analysis of two prospective studies including 128 patients with newly diagnosed mild asthma, both the ICS-formoterol and ICS groups showed improvements in asthma control, lung function, and airway inflammation. However, the ICS-formoterol group achieved significantly greater improvements in Asthma Control Test scores, Asthma Control Questionnaire scores, large airway function (FEV₁, FEV₁/FVC), small airway function, and eosinophil reduction, particularly in patients with baseline small airway dysfunction. FEV₁ reversibility in baseline bronchodilation test was positively correlated with improvements in FEV₁, FEV₁/FVC, and eosinophil count reduction in the ICS-formoterol group. These findings support 4-week ICS-formoterol maintenance therapy as an effective initial strategy in mild asthma, with reassessment guiding longer-term management.