Scope of adjuvant therapy using roflumilast, a PDE-4 inhibitor against COVID-19

The recent pandemic of COVID-19 caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents an extraordinary challenge to identify effective drugs for prevention and treatment. The pathogenesis implicate acute respiratory disorder (ARD) which is attributed to significantly triggered "cytokine storm" and compromised immune system. This article summarizes the likely benefits of roflumilast, a Phosphodiesterase-4 (PDE-4) inhibitor as a comprehensive support COVID-19 pathogenesis. Roflumilast, a well-known anti-inflammatory and immunomodulatory drug, is protective against respiratory models of chemical and smoke induced lung damage. There is significant data which demonstrate the protective effect of PDE-4 inhibitor in respiratory viral models and is likely to be beneficial in combating COVID-19 pathogenesis. Roflumilast is effective in patients with severe COPD by reducing the rate of exacerbations with the improvement of the lung function, which might further be beneficial for better clinical outcomes in COVID-19 patients. However, further clinical trials are warranted to examine this conjecture.