TY - JOUR T1 - A safe inhaled alkaline treatment that inhibits respiratory viral infections in a dose-dependent manner JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2021.OA1615 VL - 58 IS - suppl 65 SP - OA1615 AU - Jessica Saunders AU - Ryan Relich AU - Laura Smith AU - Benjamin Gaston AU - Michael Davis Y1 - 2021/09/05 UR - http://erj.ersjournals.com/content/58/suppl_65/OA1615.abstract N2 - Viral respiratory infection causes significant mortality and morbidity. Most respiratory viruses require an acidic intracellular and endosomal environment to enter cells and replicate. Optate is a safe inhaled alkaline drug that raises airway pH in vivo and inhibits SARS-CoV-2 infection in primary human airway epithelial cells (HAECs). We hypothesized that this effect was dose dependent and would also inhibit other viral infections.Cells infected with SARS-CoV-2, influenza A (FluA), influenza B (FluB), respiratory syncytial virus (RSV) or human rhinovirus (HRV) and treated Optate or placebo. A dose-response curve was performend on cells infected with SARS-CoV-2. Infection was quantified by nucleocapsid protein analysis (SARS-CoV-2) or fluorescent antibody tagging and microscopy (FluA, FluB, RSV).All viruses in this study were significantly inhibited in cells treated with Optate compared to placebo (Figure, n=4, p<0.0001 in all groups). No cytotoxicity was observed by visual evaluation (<5%) compared to the placebo.Optate inhibits SARS-CoV-2, FluA, FluB, and RSV infection without causing cytotoxicity. These effects are dose dependent for SARS-CoV-2. These findings, paired with the knowledge that Optate is safe for inhalation in humans, suggest that Optate may have therapeutic potential for patients with respiratory viral infections.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, OA1615.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). ER -