Here's a recent review: https://www.sciencedirect.com/science/article/pii/S088394412...

They find hundreds of relevant-sounding papers, registered trials, and guidelines, but almost no data beyond one in vitro study to back it up. That one study is promising--and it'll be great to see what the trials show--but the road from "works in a dish" to "drugs for all" is a long, bumpy one at the best of times.

We need to do this right so that if it works, we know that it works, and if it doesn't, we can make informed decisions to do something else.

That's nice, but most science isn't reproducible at scale. We need to do a drug trial for SARS-CoV-2 because we need to 1)establish efficacy and 2) establish safety for this drug in this disease. There are a significant amount of adverse drug effects in individual infectious diseases. Jarisch–Herxheimer reaction when treating syphilis, epstein-Barr mononucleosis and penicillin; Reye syndrome with Aspirin and influenza. The list is long here. We want the most vetted research possible because even if the chance of death is less than half a percent, half a percent of what seems like is going to be over a million is going to be in the tens of thousands here.

Furthermore, there is a difference between observations of aggregate numbers, like the number of people on ventilators and their survival rate, and small numbers of uncontrolled drug interventions where there are obvious ways for the data to be deceiving. Not all observed data has the same reliability.