One blood eosinophil count is sufficient to guide ICS therapy

Blood eosinophil count is a marker for the response of chronic obstructive pulmonary disease (COPD) patients to inhaled corticosteroids (ICS). A post-hoc analysis of the IMPACT trial showed that a single assessment of eosinophils is sufficient to guide treatment decisions for ICS [1].

Recent studies have demonstrated a positive correlation between blood eosinophil count in COPD patients and the magnitude of response to ICS in terms of exacerbation [2]. As Prof. Mona Bafadhel (University of Oxford, United Kingdom) pointed out, current GOLD guidelines recommend using blood eosinophil counts to assist clinicians in predicting the likelihood of beneficial response to ICS [3]. As there is a high intra-individual variation of eosinophils, it is not clear how many eosinophil measurements are sufficient to predict ICS response in COPD.

In their study, Prof. Bafadhel and colleagues used data from the IMPACT trial. In this trial, the magnitude of benefit of regimens containing ICS (i.e. the triple combination fluticasone furoate, umeclidinium, and vilanterol) in reducing rates of exacerbation increased in proportion with blood eosinophil counts compared with a non-ICS, dual, long-acting bronchodilator [4]. The current analysis assessed whether 1 or 2 measurements of eosinophils is sufficient to predict ICS response [1].

All 5 blood eosinophil count measurements assessed in the IMPACT trial predicted response to ICS, even when considering different covariates (e.g. exacerbation history). However, the best fitting model was the blood eosinophil count measured at study randomisation.

As Prof. Bafadhel concluded, according to this analysis of the IMPACT trial, a second blood eosinophil count measurement appears not to provide additional information to predict ICS exposure in COPD versus a single value.

1. 
   
   1. Bafadhel M, et al. Abstract 1358, ERS 2019, 29 Sept-2 Oct, Madrid, Spain.
   2.  Pascoe S, et al. Lancet Respir Med 2018;6(5):e18.
   3. Global Initiative of Chronic Obstructive Lung Disease. 2019 Report. Retrieved from https://goldcopd.org (accessed on 30 Sept 2019).
   4. Pascoe S, et al. Lancet Respir Med 2019;7(9):745-56.

 



Posted on 28 November, 201923 April, 2024