Zobel said:
The inadequacy of a proposed MoA and the challenges associated with achieving this kind of effect in a clinical setting has already been laid out for you. It's not enough. Every drug that goes to human clinical trials has a promising in vitro effect or proposed MoA. That's why they think it's worth it to try them. And even so, 90%+ of drugs that go to clinical trails fail, because medicine is hard.
Failures can indeed arise from a lack of efficacy. But there are many other reasons drugs "fail" clinical trials - there are issues with safety, or a lack of funding to complete a trial, as well as other factors such as failing to maintain good manufacturing protocols, failing to follow FDA guidance, or problems with patient recruitment, enrollment, and retention.
Only 57% fail due to "efficacy" and even then, there are many reasons that potentially efficacious drugs can still fail to demonstrate efficacy, including a flawed study design, an inappropriate statistical endpoint, or simply having an underpowered clinical trial (i.e., sample size too small to reject the null hypothesis), which may result from patient dropouts and insufficient enrollment.
There are far more studies indicating efficacy and safety of Ivermectin as a potential Covid therapeutic than those that indicate otherwise. To blithely dismiss the overwhelming majority of studies without reference to some methodological flaw because there are a few contradictory studies seems unscientific, especially in light of the success reported by actual treating physicians. I don't care one way or the other, but find the certainty with which laypersons dismiss such evidence amusing.