My friend has to take a rat and surgically implant an EEG electrodes to their brains, then put the processing unit in their belly, sew them back up. They typically die within 3 weeks or so, usually in a lot of pain.. but the researchers gather valuable data regarding their lifecycle.

With this method, they've been able to develop medication for a few diseases that save thousands to tens of thousands of humans a year (related to epilepsy).

Is it wrong?

Morally, more people are saved from this experiment, than the rats that gave their lives and far more "suffering" has been removed. On the other hand, that depends on your moral code. For me, it's about "what helps / makes me suffer less (short and long-term", so I think it's fine! For others, it's society, it's about the net positive for society - for them it's also fine. So, really, it's just those who empathize with the animals; which I think we all do, we just balance the perspective.

Personally, I couldn't do it, but I support the net gain to society.