Ensifentrine Added on to Dual Bronchodilator or Triple Therapy Demonstrates Clinically Meaningful Improvement in CAT Score in Symptomatic Patients with Chronic Obstructive Pulmonary Disease

Background: Many patients with chronic obstructive pulmonary disease (COPD) remain symptomatic despite the use of available maintenance therapies. Ensifentrine is a novel, selective, dual inhibitor of phosphodiesterase (PDE)3 and PDE4 approved for use as a maintenance therapy in adult patients with COPD. This study evaluated the effect of ensifentrine added on to dual or triple therapy on symptoms and health status in symptomatic patients with COPD using the COPD Assessment Test™ (CAT). Methods: In this single-center, Phase 3b, open-label study, patients aged 40 to 80 years with symptomatic (modified Medical Research Council Dyspnea Scale ≥2; CAT ≥10), moderate to severe COPD on stable dual bronchodilator or triple therapy received 3 mg twice-daily nebulized ensifentrine for 12 weeks. CAT scores were assessed at baseline, week 6, and week 12. Results: Twenty eligible patients received ensifentrine. Patients with ≥1 postdose assessment (n=18) were analyzed. After 12 weeks, ensifentrine improved CAT scores by ≥2 units in 67.0% (95% CI, 38.0%, 100.0%) of patients. Mean change from baseline was -2.3 units (95% CI, -4.0, -0.6), exceeding the clinically important difference of -2 units. At week 6, 44.4% (95% CI, 22.0%, 89.5%) of patients were CAT responders; the mean change from baseline in CAT score was -1.5 units (95% CI, -4.0, 1.1). No adverse events were reported. Conclusion: Ensifentrine provided clinically meaningful improvement in health status measured by CAT score in two-thirds of symptomatic patients with COPD taking dual bronchodilator or triple therapy in a real-world setting. Clinical Trial Registration Number: Clinical trial registered on June 10, 2024, with Clinicaltrials.gov (Identifier: NCT06460493).