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bioRxiv · 10.1101/2020.12.21.423779

Cetylpyridinium chloride-containing mouthwashes reduce in vitro SARS-CoV-2 infectivity

Munoz-Basagoiti, J.·Perez-Zsolt, D.·Leon, R.·Blanc, V.·Gispert, J.·Clotet, B.·Izquierdo-Useros, N.
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Abstract

Oral mouthwashes decrease the infectivity of several respiratory viruses including SARS-CoV-2. However, the precise agents with antiviral activity present in these oral rinses and their exact mechanism of action remain unknown. Here we show that Cetylpyridinium chloride (CPC), a quaternary ammonium compound present in many oral mouthwashes, reduces SARS-CoV-2 infectivity by inhibiting the viral fusion step with target cells after disrupting the integrity of the viral envelope. We also found that CPC-containing mouth rinses decreased more than a thousand times the infectivity of SARS-CoV-2 in vitro, while the corresponding vehicles had no effect. This activity was effective for different SARS-CoV-2 variants, including the B.1.1.7 variant, predominant in UK, also in the presence of sterilized saliva. CPC-containing mouth rinses could therefore represent a cost-effective measure to reduce SARS-CoV-2 infectivity in saliva, aiding to reduce viral transmission from infected individuals regardless of the variants they are infected with.

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Munoz-Basagoiti, J., Perez-Zsolt, D., Leon, R., Blanc, V., Gispert, J., Clotet, B., Izquierdo-Useros, N.. 2020-12-21. Cetylpyridinium chloride-containing mouthwashes reduce in vitro SARS-CoV-2 infectivity. https://doi.org/10.1101/2020.12.21.423779

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