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This nationwide UK study of severe asthma patients eligible for biologic therapy identified three distinct exacerbation trajectories over time: a majority experienced remitting-stable courses with reduced exacerbations under standard care; a smaller subset had persistent frequent exacerbations associated with higher eosinophil counts, indicative of a distinct inflammatory phenotype; and a refractory group endured high corticosteroid exposure. These findings challenge assumptions that biologics are universally needed immediately upon eligibility and emphasize the heterogeneity of severe asthma progression.

