Chloroquine is a really interesting drug because it is derived from quinine which is one of those "early history medicine man/woman" kinda things (Quechas) that turned out to be effective for two things: antiviral properties and great taste.

* It was used for centuries to combat malaria until it recently (~10yrs) became ineffective (I took some in the 80's for a year while working in Central America and had amazing dreams).

* It is the basis many awesome aperitifs: Byrrh, Bonal, [tonic water,] and other herbaceous spirits

If it can be used as an antiviral for COVID-19, well, that would be a really cool example of an old/ancient medicine still doin' its thing.