Patient-Reported Outcomes (PROs) in COPD Clinical Trials: Trends and Gaps

Key characteristics of chronic obstructive pulmonary disease (COPD) that significantly affect health-related quality of life (HRQoL) include chest symptoms, dyspnea, cough, sputum production, and exacerbations. Additional areas of impact are sleep, fatigue, emotional well-being, social functioning, and coping. Patient-reported outcomes (PROs) are essential to evaluate symptoms, impact of symptoms on activities of daily living, and treatment response. This review summarizes COPD-specific PRO endpoints from randomized controlled trials of approved and commonly used COPD drugs. A search conducted in "ClinicalTrials.gov" to identify COPD clinical trials (only completed Phase III and IV) incorporating PRO endpoints yielded a total of 104 clinical trials for inclusion in this analysis. Both symptom-based and HRQoL-specific PRO measures were reported. Several COPD-specific PRO measures are available; however, the St. George's Respiratory Questionnaire (SGRQ) and the Baseline and Transition Dyspnea Indexes (BDI/TDI) were reported in the majority of the studies. Results reflected a gap in terms of full coverage of key impacted areas from a patient's perspective. Methodological issues identified in this review related to scoring of instruments require careful consideration, as these challenges may limit the complete assessment of drug benefits. Selection of PRO measures aligned with the expected treatment benefit of a drug in a clinical trial should reflect patients' perspective holistically.