Abstract
BACKGROUND: This study evaluated the efficacy, safety and tolerability of the novel inhaled phosphodiesterase-4 inhibitor CHF6001 added-on to formoterol in patients with chronic obstructive pulmonary disease (COPD). METHODS: Randomised, double-blind, placebo- and active-controlled, parallel-group study. Eligible patients had symptomatic COPD, post-bronchodilator forced expiratory volume in 1 s (FEV(1)) 30-70% predicted, and history of ≥1 moderate/severe exacerbation. Patients were randomised to extrafine CHF6001 400, 800, 1200 or 1600 μg twice daily (BID), budesonide, or placebo for 24 weeks. PRIMARY OBJECTIVES: To investigate CHF6001 dose-response for pre-dose FEV(1) after 12 weeks, and to identify the optimal dose. Moderate-to-severe exacerbations were a secondary endpoint. RESULTS: Of 1130 patients randomised, 91.9% completed. Changes from baseline in pre-dose FEV(1) at Week 12 were small in all groups (including budesonide), with no CHF6001 dose-response, and no significant treatment-placebo differences. For moderate-to-severe exacerbations, CHF6001 rate reductions versus placebo were 13-28% (non-significant). In post-hoc analyses, CHF6001 effects were larger in patients with a chronic bronchitis phenotype (rate reductions versus placebo 24-37%; non-significant), and were further increased in patients with chronic bronchitis and eosinophil count ≥150 cells/μL (49-73%, statistically significant for CHF6001 800 and 1600 μg BID). CHF6001 was well tolerated with no safety signal (including in terms of gastrointestinal adverse events). CONCLUSIONS: CHF6001 had no effect in the primary lung function analysis, although was well-tolerated with no gastrointestinal adverse event signal. Post-hoc analyses focused on exacerbation risk indicate specific patient subgroups who may receive particular benefit from CHF6001. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT02986321 ). Registered 8 Dec 2016.