RT Journal Article SR Electronic T1 The effectiveness of anti-IL5 biologics is comparable in previous-smokers and never-smokers with severe asthma JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA3742 DO 10.1183/13993003.congress-2021.PA3742 VO 58 IS suppl 65 A1 Susanne Hansen A1 Charlotte Ulrik A1 Ole Hilberg A1 Anna Von Bülow A1 Anders Christiansen A1 Claus R Johnsen A1 Johannes Schmid A1 Anne Sofie Bjerrum A1 Karin Assing A1 Alexandra Wimmer-Aune A1 Niels Krogh A1 Linda Rasmussen A1 Celeste Porsbjerg YR 2021 UL http://erj.ersjournals.com/content/58/suppl_65/PA3742.abstract AB Background: Anti-IL5/anti-IL5-receptor treatment for severe asthma has demonstrated to be effective in randomized controlled trials. However, such trials do not include patients with a significant smoking history, and little is known about the effectiveness in previous smokers.Objective: To assess whether previous smoking modifies the effectiveness of anti-IL5/anti-IL5 receptor treatment.Methods: Patients in the Danish Severe Asthma Register treated with mepolizumab, reslizumab or benralizumab for at least 12 months were included. Percent change in the number of exacerbations and forced expiratory volume in the 1st second of predicted value (FEV1%) and change in mean Asthma Control Questionnaire (ACQ) score from baseline to 12 months were analyzed as continuous variables, adjusting for smoking status, age and sex.Results: At start of treatment, 132 (44%) were previous smokers with a mean (standard deviation) packyears of 19 (15.6) years and 171 (56%) were never-smokers. After one year of treatment, the number of exacerbations was reduced by 68% (95% confidence interval (CI):55-80) in never-smokers and 54% (43-64) in previous smokers, p=0.10. ACQ score improved with -1.06 (-1.40, -0.72) in previous smokers and -1.03 (-1.37, -0.68) in never-smokers, p=0.91, and FEV1% increased by 13% (7-19) in previous smokers and 11% (4-18) in never-smokers, p=0.63.Conclusion: In a nationwide cohort of patients with severe asthma, the effectiveness of anti-IL5/anti-Il5 receptor treatment was comparable in previous smokers and never-smokers, suggesting that a significant smoking history does not preclude a clinical effect of biological therapy.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3742.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).