So one set of studies and done right?
Well, no. It took a while to get to that phase. This is how medicine works. We start with in vitro studies, infecting cells in a petri dish and seeing if hydroxychloroquine worked. Then we move on to observational studies. People reporting that they tried it on a series of patients. These are retrospective and not controlled, which means they're prone to error. Confounding factors can sneak in, but they're good enough to warrant further investigation. If those are all positive, then we move on to randomized clinical trials. RCTs are gold standard. They are the least likely to be affected by confounding or bias. If the RCT is negative, that's the strongest possible evidence. We find often that observational studies show one thing and the RCT shows another, and since the RCT is the better study, we go with that.
So that's what happened. Observational retrospective trials were positive, so we moved onto RCTs. The RCTs were negative so the drug fell out of favor. It's not just our big RCT that was negative. There were others in the UK and Europe that were negative as well.
This is how medicine works. It doesn't care what Trump says. It just did the work that it always does.
So why did the FDA pull the emergency approval for hydroxychloroquine? Were they all affected by TDS? That's what I've been told here.