You attempt to separate what animals have in common with H. sapiens, which is also part of the science.YES!
The main reason being that clinical trials are animals usually are fairly useless.
You use science to determine the probable danger, then pay test patients well for increasing doses.
It is much quicker, accurate, and productive to ONLY use human subjects.
Using animals is pretty much just stupid, a waste of time, and worthless.
Animals have very different physiology and their results are totally skewed by the stress factors.