The Effect of Inhaled Corticosteroid Withdrawal and Baseline Inhaled Treatment on Exacerbations in the IMPACT Study. A Randomized, Double-Blind, Multicenter Clinical Trial

Abstract

<b>Rationale:</b> In the IMPACT (Informing the Pathway of Chronic Obstructive Pulmonary Disease Treatment) trial, fluticasone furoate (FF)/umeclidinium (UMEC)/vilanterol (VI) significantly reduced exacerbations compared with FF/VI or UMEC/VI in patients with symptomatic chronic obstructive pulmonary disease and a history of exacerbations.<b>Objectives:</b> To understand whether inhaled corticosteroid (ICS) withdrawal affected IMPACT results, given direct transition from prior maintenance medication to study medication at randomization.<b>Methods:</b> Exacerbations and change from baseline in trough FEV₁ and St. George's Respiratory Questionnaire results were analyzed by prior ICS use. Exacerbations were also analyzed while excluding data from the first 30 days.<b>Measurements and Main Results:</b> FF/UMEC/VI significantly reduced the annual moderate/severe exacerbation rate compared with UMEC/VI in prior ICS users (29% reduction; <i>P</i> < 0.001), but only a numerical reduction was seen among prior ICS nonusers (12% reduction; <i>P</i> = 0.115). To minimize impact from ICS withdrawal, in an analysis excluding the first 30 days, FF/UMEC/VI continued to significantly reduce the annual on-treatment moderate/severe exacerbation rate (19%; <i>P</i> < 0.001) compared with UMEC/VI. The benefit of FF/UMEC/VI compared with UMEC/VI was seen for severe exacerbation rates, regardless of prior ICS use (prior ICS users, 35% reduction; <i>P</i> < 0.001; non-ICS users, 35% reduction; <i>P</i> = 0.018), and overall when excluding the first 30 days (29%; <i>P</i> < 0.001). Improvements from baseline with FF/UMEC/VI compared with UMEC/VI were also maintained throughout the study for both trough FEV₁ and St. George's Respiratory Questionnaire, regardless of prior ICS use.<b>Conclusions:</b> These data support the important treatment effects of FF/UMEC/VI combination therapy on exacerbation reduction, lung function, and quality of life that do not appear to be related to abrupt ICS withdrawal.Clinical trial registered with www.clinicaltrials.gov (NCT02164513).