I fundamentally disagree. We have models, sure, but they're approximative, not predictive, and I don't see any indication we'd be able to get prediction ever. It's very difficult to understand how biological approximation layered over chemical and physical approximation could give any benefit we get now from experimentation.
Among other things, there is no such thing as model verification.
If we are extrapolating results from rats to humans, why can't we just simulate a rat brain and avoid torturing more? Probably because rats are cheap, and supercomputers, well, are super expensive.
I don't think it would be difficult to simulate a fully functional rat brain with state-of-the-art technology and bright people.
One day we may be able to do that, and when we can, I agree it would be nice to stop torturing rats.