This is obvious though — currently, you might test a drug on mice, then on primates, and finally on humans (as an example). It would be faster to skip the early bits and go straight to human testing.

…but that is very, very, very wrong. Science of course doesn’t care about right and wrong, nor does it care if you “believe” in it, which is the beautiful thing about science — so a scientifically sound experiment is a scientifically sound experiment regardless of ethical considerations. (Which does not mean we should be doing it of course!)

Now, taking a step back, maybe you’re right that, in the long run, throwing ethics out the window would actually slow things down, as it would (rightfully) cause backlash. But that’s getting into a whole “sociology of science” discussion.

Many kinds of early-in-life medical interventions can have permanent negative effects if they go bad, but nonetheless our ethical standards don’t preclude them. This is a field where the ethical standards are suffocatingly high without good reason. As an aside, we should consider euthanizing newborns who suffer debilitatingly severe negative side effects due to any kind of failed medical intervention (with parental consent, of course). This will directly improve quality-of-life standards and also allow us to lower ethical standards on experimental treatments too.