Beyond biologics: background inhaled therapy shapes remission in severe asthma

Clinical remission is an achievable therapeutic goal in severe asthma treated with biologics, but the influence of background inhaled therapy on remission remains unclear. We evaluated whether baseline inhaled therapy, particularly extrafine single-inhaler triple therapy (SITT), affects the achievement of complete clinical remission.

This single-center retrospective study included adults with severe asthma initiating biologic therapy according to Italian regulatory criteria. Baseline corresponded to biologic initiation without changes in inhaled treatment, which remained unchanged throughout 12 months. Patients were reassessed after 3 months to evaluate asthma control, adherence, and exacerbations. Complete remission at 12 months was defined according to Severe Asthma Network Italy criteria: no exacerbations, ACT ≥20, no oral corticosteroid use, stable lung function, and no change in inhaled therapy. Clinical, functional, and inflammatory variables were compared between remission and non-remission groups.

Twenty-nine patients were included (median age 53 years; 55.2% male). Baseline inhaled therapy consisted of high-dose ICS/LABA (37.9%), open triple therapy (27.6%), and extrafine SITT (34.5%). No patient required inhaled therapy modification during follow-up. After 12 months, 14 patients (48.3%) achieved complete remission. Remission differed significantly according to inhaled therapy (p=0.001), occurring most frequently with extrafine SITT (64.3%), followed by open triple therapy (21.4%) and ICS/LABA (14.3%). Patients achieving remission were more likely to receive extrafine SITT at baseline, while ICS/LABA predominated in non-remission patients. No differences were observed in demographics, lung function, biomarkers, comorbidities, or biologic therapy.

Baseline extrafine SITT was associated with a greater likelihood of complete clinical remission in severe asthma treated with biologics, supporting the importance of optimized background inhaled therapy within remission-oriented management. Prospective studies are needed to confirm these findings.