Although far from "standardized treatment", this site
https://c19early.com/ has a list of things that have been studied for the treatment of Covid-19. Lot of compounds are certainly "not ready for prime time", but if you look at the number of studies and the number of patients, and validate the range doesn't break through unity (crosses "1", which means the result is not statistically significant), you can get an idea of how well studied various compounds are for this indication, and how well they've done (farther to the left is better). Note that "bamlanivimab" is what you might get if you get "monoclonal antibodies", or you might get "casirivimab/imdevimab".