The initial results of a non-peer-reviewed Cardiff University “The Virucidal Efficacy of Oral Rinse Components Against SARS-CoV-2 In Vitro‘ showed “promising signs” of mouthwashes containing at least 0.07 per cent cetypyridinium chloride (CPC) being capable of combatting the coronavirus virus.  https://www.biorxiv.org/content/10.1101/2020.11.13.381079v1.full.pdf