Composite endpoints in COPD: clinically important deterioration in the UPLIFT trial
Klaus F. Rabe, David Halpin, MeiLan K. Han, Marc Miravitlles, Dave Singh, Lars Grönke, Florian Voß, Fernando J. Martínez
Abstract
Abstract Background Assessments of lung function, exacerbations and health status are common measures of chronic obstructive pulmonary disease (COPD) progression and treatment response in clinical trials. We hypothesised that a composite endpoint could more holistically assess clinically important deterioration (CID) in a COPD clinical trial setting. Methods A composite endpoint was tested in a post hoc analysis of 5652 patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2–4 COPD from the 4-year UPLIFT study. Patients received tiotropium 18 μg or placebo. Results The composite endpoint included time to first confirmed decrease in trough forced expiratory volume in 1 s (FEV 1 ) ≥100 mL, confirmed increase in St. George’s Respiratory Questionnaire (SGRQ) total score ≥ 4 units, or moderate/severe exacerbation. Most patients (> 80%) experienced CID, with similar incidence among GOLD subgroups. Most confirmed trough FEV 1 (74.6–81.6%) and SGRQ (72.3–78.1%) deteriorations were sustained across the study and in all GOLD subgroups. Patients with CID more frequently experienced subsequent exacerbation (hazard ratio [HR] 1.79; 95% confidence interval [CI] 1.67, 1.92) or death (HR 1.21; 95% CI 1.06, 1.39) by Month 6. CID was responsive to bronchodilator treatment. Conclusions Composite endpoints provide additional information on COPD progression and treatment effects in clinical trials. Trial registration ClinicalTrials.gov NCT00144339 . Graphical abstract