Inhaled corticosteroids downregulate SARS-CoV-2-related genes in COPD: results from a RCT.

Observational studies show that chronic obstructive pulmonary disease (COPD) is associated with increased COVID-19 severity and mortality [1]. Inhaled corticosteroids (ICS), which are commonly used to treat COPD, have been associated with increased risk of bacterial pneumonia in COPD and impaired immune response to viruses. Whether this class of medication affects the airway expression of SARS-CoV-2 receptors and cofactors – changes which may modify COVID-19 susceptibility and outcomes – is currently unclear. We therefore examined the effects of ICS treatment on SARS-CoV-2-related gene expression in lower airway bronchial epithelial cells (BECs) in a randomised controlled trial of COPD patients. Acknowledgments: The authors would like to thank the generous fundraising and donation efforts by Irving Ding and Mrs. Chun Hong Tao to St. Paul's Foundation COVID-19 Response Fund. We are grateful to Mr Ryan Vander Werff and Ms Tara Stach at BRC-Seq for conducting the RNA sequencing; and Dr Chung Cheung and Ms Julia Yang for their assistance with laboratory specimens.