[q845712]

"animal models" is a fairly standard phrase in research: When people research depression, alzheimers, cancer, etc., they generally start with mice and work their way up through monkeys before coming to human trials. For many conditions there's specific "lines" of mice that have been bred or even genetically modified to exhibit those conditions in a reliable or extreme way. Depression is particularly challenging since you can't ask an animal how it's feeling, and frankly nearly all animals used in laboratories are understimulated, removed from their natural habitat, and probably a little "depressed". (see e.g. the "rat park" studies (https://www.psychiatrictimes.com/view/what-does-rat-park-tea...) that showed that rats were much less likely to self-administer cocaine if they were in an environment that let them have a more enjoyable/fulfilling/natural life otherwise.)

So anyway "animal models" just means "an animal mice/rats/monkeys/etc. that we have decided has enough of the same symptoms of the human disease that we can use it to study treatments of that disease", and it's fairly common for something to work in mice but fail in monkeys, or even to work in both mice and monkeys but not work or have very undesirable side-effects in humans. (side note: one of the least discussed things in pharma is how they source the first humans for trialling a new treatment, which does carry non-trivial risk to the human "guinea pigs" - it's generally people who are poor and desperate.)