Sorry for the late reply: I don't see how it would prevent infection. It could be useful post-infection, to prevent complications and inflammation. Compared that with the standard of care right now which is simply observing the patient during their recovering.
There are a fair amount of studies who took the initial in vitro results (i.e. cell culture) suggesting non-specific antiviral activity (at that level coca-cola is also an antiviral, antimicrobial, and antitumoral, by the way), into animal or human, and they just did not pan out, because it isn't an antiviral.
It should help alleviating the symptoms, but is in no way a antiviral.
There's a phase 3 trial for treating pneumonia associated with coronavirus. This is based on prior work showing anti-inflammatory response in rheumatoid arthritis (https://www.ncbi.nlm.nih.gov/pubmed/8278823).
There are a fair amount of studies who took the initial in vitro results (i.e. cell culture) suggesting non-specific antiviral activity (at that level coca-cola is also an antiviral, antimicrobial, and antitumoral, by the way), into animal or human, and they just did not pan out, because it isn't an antiviral.