“Current and former smokers with spirometric values within the normal range are frequently treated with bronchodilators or inhaled corticosteroids (ICS),” explained Prof. MeiLan Han (University of Michigan, MI, USA)1-3. These individuals are however not included in current GOLD guideline recommendations and a benefit of these medications is not established.
The multicentre, randomised, phase 3 RETHINC study (NCT02867761) compared a 12-week treatment of inhaled indacaterol/glycopyrrolate with placebo in current and former smokers with preserved spirometry and respiratory symptoms (n=535)1. The primary endpoint was a 4-unit improvement on the St. George's Respiratory Questionnaire (SGRQ) without experiencing treatment failure during the treatment period. The results have been published in the New England Journal of Medicine4.
The primary outcome was achieved by 56.4% and 59.0% of the patients in the intervention arm and placebo arm, respectively (P=0.65). This result was consistent across subgroups. “COPD drugs may not alleviate symptoms in symptomatic individuals with preserved pulmonary function, because these participants do not have the typical small airway disease that is targeted by COPD medication,” argued Prof. Han.
“It is essential that individuals with suspected COPD are being tested with spirometry to select patients that may benefit from bronchodilators. Also, we need to investigate the drivers of symptoms in individuals with respiratory symptoms and preserved spirometric values.”