@article {Burkill3305, author = {S Burkill and C M. Porsbjerg and A Bourdin and T N Tran and N Martin and R Katial and P Barker and M E Wechsler and J Maspero and S Bosnic-Anticevich and L P Chung and G Katsoulotos and G C Christoff and T A Popov and M Sadatsafavi and C A Torres-Duque and C Ulrik and K Dahl Assing and S Hansen and A Altraja and L A Lehtimaki and N G Papadopoulos and K Kostikas and S Salvi and R W Costello and P Francesca and T Iwanaga and C K Rhee and M Al-Ahmad and D Larenas-Linnemann and J A Fonseca and R Amaral and K Alving and R Al-Lehebi and L Perez De-Llano and B Kirenga and M Tsai and B Mahboub and P E Pfeffer and W Henley and Y Liu and J Lyu and C Goh and T Uthaman and D Price and J Townend}, title = {Real-life biomarker response to anti-IL5 and anti-IgE therapies in severe asthma patients}, volume = {60}, number = {suppl 66}, elocation-id = {3305}, year = {2022}, doi = {10.1183/13993003.congress-2022.3305}, publisher = {European Respiratory Society}, abstract = {Introduction/Background: Biologics (Bx) are known to decrease specific biomarker levels: anti-IL5 reduces blood eosinophils (BEC) and anti-IgE slightly reduces FeNO. Anti-IL5 and anti-IgE are thought to have limited effect on total IgE (IgE).Aims and Objectives: To assess the proportions of severe asthma patients whose biomarkers (BEC, FeNO, and serum IgE) decrease following anti-IL5 and anti-IgE initiation.Methods: Patients in the International Severe Asthma Registry (ISAR) with biomarker and Bx data were included. From pre-Bx baseline to the post-Bx time period, the median (IQR) change in biomarker level and the proportion of patients with \>25\% decrease in biomarkers were determined.Results: At 2-3 years from Bx initiation, BEC decreased by \>25\% in 80.7\% of anti-IL5 and 41.6\% of anti-IgE patients. FeNO decreased by \>25\% in 41.6\% of anti-IL5 and 47.8\% of anti-IgE patients. IgE decreased by \>25\% in 41.7\% of anti-IL5 and 15.6\% of anti-IgE patients (Figure).Figure: Median (IQR) biomarker changes and patient proportions with decreased biomarkers in response to Bx.Conclusions: Anti-IL5 was superior in decreasing BEC and both Bx classes decreased FeNO to a limited extent. The lower proportion of anti-IgE patients with IgE reduction could be attributed to serum total IgE (not free IgE) measurement. Apart from anti-IL5{\textquoteright}s effect on BEC, \<50\% patients had decreased biomarkers; the clinical implications should be explored.FootnotesCite this article as Eur Respir J 2022; 60: Suppl. 66, 3305.This article was presented at the 2022 ERS International Congress, in session {\textquotedblleft}-{\textquotedblright}.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).}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/60/suppl_66/3305}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }