I've worked in labs that do animal testing. It's not done unless there are no alternatives. Animals are very well taken care of and every attempt is made to eliminate any pain or suffering.
But hey, if you're so against animal testing you should stop using anything that's been testing on an animal. That would be the logical thing. So no cancer drugs, no antibiotics, or practically any other medical.
Then you can tell me how "useless the suffering is"
I don't know about you, but that sounds like a very worthwhile goal.
Meet a typical medical student. Ever opened an anatomic atlas?
Please don't condescendingly diagnose other people for "psychopathic behavior" when you don't seem to be able to figure out the basic functioning of your fellow human, hastily dehumanizing them.