Early Changes in eDiary COPD Symptoms Predict Clinically Relevant Treatment Response at 12 Weeks: Analysis from the...

Early detection of treatment response is important in the long-term treatment and management of patients with chronic obstructive pulmonary disease (COPD). This analysis evaluated whether early improvement in symptoms, recorded in the first 7 or 14 days via an electronic diary (eDiary) compared with baseline, can predict clinically meaningful treatment responders at 12 weeks. CRYSTAL was a 12-week, randomized, open-label study that demonstrated the increased effectiveness of indacaterol/glycopyrronium (IND/GLY) or glycopyrronium (GLY), after a direct switch from on-going baseline therapies, in patients with symptomatic COPD and moderate airflow obstruction. The co-primary endpoints were trough forced expiratory volume in 1 second (FEV₁) and transition dyspnea index (TDI) at Week 12. Patients' symptom status was recorded daily in an eDiary. Of 4,389 patients randomized, 3,936 and 3,855 reported symptoms on Days 7 and 14, respectively. Patients who reported an early decrease in symptoms on Day 7 or 14 were more likely to achieve the minimal clinically important difference of ≥100 mL in trough FEV₁ or ≥ 1 point in TDI at Week 12. Using stepwise multivariate regression models we identified as best predictors of FEV₁ responders the decrease in wheeze on Day 7, and nighttime symptoms and wheeze on Day 14; best predictors of TDI responders were decrease in nighttime symptoms and wheeze on Day 7, and nighttime symptoms, sputum and wheeze on Day 14. Early symptom improvement at Day 7 or 14, especially wheeze and nighttime symptoms, may identify patients with clinically important improvement in lung function and dyspnea at Week 12.