Another drug used widely could work against the COVID-19 virus. Invermectin is widely used around the world in veterinary and human medicine. An antihelmintic, it's used to treat river blindness and other parasitic diseases. A couple of links to an article about Aussie doctors using it to treat covid-19 with success so far and a medical paper describing Invermectin.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3043740/
https://truepundit.com/common-anti-parasite-drug-may-kill-coronavirus-in-under-48-hours-say-researchers/