“The leading U.S. manufacturer of xylitol-based products says the federal government is deliberately trying to conceal a nasal spray it developed that it says has been scientifically proven to be effective in treating and preventing COVID-19.”

This is an update to a post about this several months ago. For you conspiracy theorists, this probably means there is some efficacy.

https://www.zerohedge.com/covid-19/feds-seek-block-promotion-nasal-spray-against-covid-19