Predictive Factors And Treatments Associated with Clinical Remission in Severe Eosinophilic Asthma.

Severe eosinophilic asthma represents a relatively small proportion of the overall asthma population but accounts for a disproportionate burden of exacerbations, oral corticosteroid (OCS) exposure and healthcare use. The advent of biologic therapies targeting type 2 (T2) inflammation has made clinical remission a realistic goal and raised new questions about how and when to de-escalate inhaled corticosteroids (ICS) and biologics in patients achieving stable disease. This narrative review summarizes current evidence and expert recommendations on: definitions and levels of clinical remission in severe eosinophilic asthma; the role of different biologics in inducing remission; safety and feasibility of ICS and biologic de-escalation after remission; and clinical and biological predictors of sustained remission and successful step-down. Biologics such as anti-IgE, anti-IL-5/5Rα, anti-IL-4Rα and anti-thymic stromal lymphopoietin (TSLP) markedly reduce exacerbations, OCS use and, in a substantial minority of patients, induce clinical or "deep" remission on-treatment. Prospective randomized controlled trials and real-world data (e.g. SHAMAL and registry studies) indicate that structured, physician-guided ICS reduction is feasible for many patients without loss of control, whereas abrupt or unsupervised reduction is associated with worse outcomes. Evidence on biologic withdrawal is more heterogeneous: discontinuation of mepolizumab, tezepelumab or omalizumab frequently leads to loss of control, although a subset maintains remission off-treatment. Favorable predictors of remission and tolerability of de-escalation include fewer prior exacerbations, lower chronic OCS exposure, shorter disease duration, better preserved FEV