Higher COPD Assessment Test Score Associated With Greater Exacerbations Risk: A Post Hoc Analysis of the IMPACT Trial

Background: In the InforMing the PAthway of COPD Treatment (IMPACT) trial, single-inhaler fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) reduced moderate/severe exacerbation rates versus FF/VI and UMEC/VI in patients with chronic obstructive pulmonary disease (COPD). This post hoc analysis tested the relationship between baseline health status, risk of future exacerbations, and efficacy outcomes.

Methods: IMPACT was a Phase 3, double-blind, 52-week trial in patients with symptomatic COPD (COPD Assessment Test [CAT] score ≥10) and ≥1 moderate/severe exacerbation in the prior year randomized 2:2:1 to FF/UMEC/VI 100/62.5/25mcg, FF/VI 100/25mcg, or UMEC/VI 62.5/25mcg. Annual rate of on-treatment moderate/severe exacerbations, lung function, and safety were analyzed by continuous baseline CAT score.

Results: Moderate/severe exacerbation rates increased with increasing baseline CAT scores in FF/UMEC/VI and UMEC/VI arms. There was a very small increase in on-treatment pneumonia rates at higher baseline CAT scores across all treatment arms. FF/UMEC/VI reduced moderate/severe exacerbation rates versus UMEC/VI (i.e., the inhaled corticosteroid effect) consistently across the range of CAT scores. The reduction with FF/UMEC/VI versus FF/VI (i.e., the long-acting muscarinic antagonist effect) was greatest at lower CAT scores and appeared lesser at higher CAT scores. Improvements in lung function were observed with FF/UMEC/VI versus FF/VI and UMEC/VI, regardless of baseline CAT score.

Conclusions: The CAT score was predictive of exacerbation risk. Worse baseline health status was associated with higher moderate/severe exacerbation and pneumonia rates. Irrespective of baseline CAT score, FF/UMEC/VI improved lung function, and reduced the annual moderate/severe exacerbation rates versus dual therapy. Results indicate an overall favorable benefit-risk profile of triple versus dual therapy, irrespective of CAT score. Clinical Trial Registration:GSK (CTT116855/NCT02164513).