Use of the evaluating respiratory symptoms™ in COPD as an outcome measure in clinical trials: A rapid systematic review

Abstract

Rationale: Patients with chronic obstructive pulmonary disease (COPD) struggle with respiratory symptoms that impair their daily activities and quality of life. Understanding a treatment's ability to relieve symptoms requires precise assessment. The Evaluating Respiratory Symptoms in COPD (E-RSTM:COPD) was developed to quantify respiratory symptoms in clinical trials. This review study aimed to better understand how trials use this patient-reported outcome measure as an endpoint, as well as its responsiveness and performance relative to other outcome measures. Objectives: To summarize the use of the E-RS:COPD in pharmacological trials since its qualification by regulatory authorities. Methods: A rapid systematic literature review, using key biomedical databases to identify English language full-text publications of randomized controlled trials (RCTs) that included the E-RS:COPD as an endpoint (2010-2020), was conducted. Two investigators independently screened the publications and extracted data. Measurements and Main Results: Of 219 screened records, 28 full-text publications were included, and data from 17 reporting 20 unique double-blind RCTs were synthesized. The E-RS:COPD was positioned as a primary or secondary endpoint in 6 publications (35%), and served as an exploratory or additional endpoint in 11 (65%). Statistically significant E-RS:COPD treatment effects versus placebo/comparator were found in 13 of the 14 publications reporting symptom results. E-RS:COPD effects corresponded well with other outcome measures (e.g., St George's Respiratory Questionnaire [SGRQ] and forced expiratory volume in 1 second [FEV1]). Two publications reported the number of responders. Conclusions: E-RS:COPD is sensitive to treatment effects in clinical trials testing drug therapies. Presentation of trial results should include responder analyses to facilitate interpretation and application of results.