RT Journal Article SR Electronic T1 Omalizumab in severe allergic asthma associated with COPD: a multicentric cohort study JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA3738 DO 10.1183/13993003.congress-2021.PA3738 VO 58 IS suppl 65 A1 Pereira, Sophie A1 Bautin, Nathalie A1 Verhille, Juliette A1 Bonniaud, Philippe A1 Devouassoux, Gilles A1 Fry, Stephanie A1 Guilleminault, Laurent A1 Khayath, Naji A1 Leroyer, Christophe A1 Chenivesse, Cecile A1 Bautin, Nathalie YR 2021 UL http://erj.ersjournals.com/content/58/suppl_65/PA3738.abstract AB Omalizumab is a treatment for severe uncontrolled allergic asthma. Few data are available on its efficacy when asthma coexists with chronic obstructive pulmonary disease (COPD), although overlap (ACO) is common. Our study aimed to describe the characteristics of ACO patients treated with omalizumab.Method: Retrospective data from consecutive asthmatic patients treated with omalizumab between 2010 and 2019 in 6 French university hospitals. ACO criteria were: age > 40 years, smoking > 10 pack-years, post-bronchodilator FEV1/FVC < LLN. Data collection included: mMRC dyspnea scale, asthma control test (ACT), exacerbations rate and FEV1, before and after 3 and 12 months of treatment.Results: Among 701 severe allergic asthmatics treated with omalizumab, 123 had ACO criteria (17%). ACO patients (n=101 with complete data) were 58 years old [52;65], 59% were male with smoking history of 20 pack-years [15;30], mMRC 3 [2;3], ACT 12 [9;16], 6 exacerbations in the previous year [4;12] and FEV1 63 % pred [46;76].At 3 months, mMRC improved from 3 [2;3] to 2 [1;3]* and ACT from 12 [9;16] to 15 [12;21]*. 28 patients discontinued omalizumab before 12 months, mainly because of treatment failure.At 12 months, in the 73 patients who continued omalizumab, mMRC improved from 3 [2;3] to 2 [1;2]*, ACT from 12 [9;16] to 18 [14;23]* and exacerbation rate decreased from 6 in the previous year [4;10] to 1 during the year of treatment [0;2]*, with no change in FEV1. * p < 0,001Conclusion: In severe allergic asthma coexisting with COPD, omalizumab was discontinued in 28% of patients. In those who continued, omalizumab use was associated with an improvement of dyspnea, asthma symptoms and exacerbations rate.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3738.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).