German Asthma Net: Characterisation of responders to anti-IL-5 and anti-IL-5(R) therapy.

Introduction: Previous studies of anti-IL-5/IL-5(R) therapies in severe asthma found that response was mainly predicted by indicators of good baseline disease control. However, long-term response predictors remain unclear.

Methods: Responders to anti-IL-5/IL-5(R) therapy in the well-characterised, real-life, international German Asthma Net (GAN) registry were analysed using regression analyses. Response was defined by ≥50% reduction in exacerbations or corticosteroid dose, super-response by a complete stop of both, and remission additionally by controlled asthma (ACT score≥20).

Results: Seventy-seven percent of 347 patients (55% female, 56.6±12.3 years, follow-up 20.3±13 months) were responders and showed improved exacerbation rates, asthma control, and corticosteroid treatment reduction. Response was independently predicted by inhaled corticosteroid dose (odds ratio [OR] 1.5; p = 0.014), exacerbation rate (OR 1.2; p = 0.009), and treatment duration (OR 1.05, p = 0.023). Univariately, blood eosinophil counts notably predicted response (OR 12.4; p = 0.004). Super-response was inversely associated with corticosteroid dependence and depression. Remission was associated with the absence of systemic corticosteroids, better asthma control, and FEV1 in litre.

Conclusions: These results underscore that long-term anti-IL-5/IL-5(R) therapy reduces exacerbation and corticosteroid burden, especially in patients with severe disease and high type 2 inflammatory burden. Contrastingly, low baseline corticosteroid use and markers of good asthma control predicted remission and super-responder status.