Cetylpyridinium chloride as Treatments for COVID-19

The experimental indicated a high-frequency of quaternary ammonium disinfectants as treatments for many viruses, including coronaviruses: these act by deactivating the protective lipid coating that enveloped viruses like SARS-CoV-2 rely on. Quaternary ammonium compounds are widely recommended to kill viruses and there are over 350 products on EPA’s List N: Disinfectants for use against SARS-CoV-2 (Supplementary Material. The disinfectant concentrations and contact times (associated with multiple viruses) for many of the disinfecting chemicals on the EPA list have been reported and > 140 can deactivate the virus in just a few minutes (18).
This information led us on a larger search for quaternary ammonium compounds with activity against coronaviruses and possible identification of chemicals that have already been tested in the clinic and could be used as a potential treatment for COVID-19 . One of the disinfectants that has been shown to be destructive to viruses (Supplementary Material) and widely used in personal care products is cetylpyridinium chloride. This compound is found predominantly in mouthwashes and is listed by the FDA as Generally Regarded as Safe (GRAS) such that it is also being used as an antimicrobial agent for meat and poultry products (up to 1%). Cetylpyridinium chloride has been used in multiple clinical trials, including as a treatment against respiratory infections validating its use as an antiviral. Cetylpyridinium likely promotes virus inactivation by destroying the capsid as well as through its lysosomotropic action, which, as discussed above, is common for quaternary ammonium compounds. This raises the question as to whether some of the drugs identified with antiviral activity against SARS-CoV-2 in vitro behave similarly, namely they may destroy the virus capsid as well as accumulating in the lysosome or endosomes and ultimately blocking viral entry. Additional published studies have suggested that this effect can be attenuated by the use of Cathepsin-L inhibitors. 

 Cetylpyridinium chloride(CPC)

Quaternary ammonium compounds with known coronavirus activity