There's a certain environmental analogy in the film: some vampires ask their complacent colleagues what will happen when they've drunk the last human blood (there will always be more is the answer). I think we have an even better analogy, though.
McClatchy reports that the US is considering restarting the use of chimpanzees for medical experiments. Just like some vampires in the fictional movie believed it was wrong to use their closely related species of humans, however inferior the humans might be, many people and even a major pharmaceutical company (GlaxoSmithKline) oppose this experimentation on great apes.
McClatchy's reporting is good and detailed and has two flaws: first, it's not clear exactly how the chimps would be used. Many were previously infected with Hepatitis C, so this research could potentially benefit them. More to the point, any research that doesn't hurt, scare, or medically harm the chimps isn't too controversial. I think the researchers' comparison to human volunteers doesn't work, though: you don't have shoot human subjects with anesthetic darts on a daily basis in order to get blood samples from them. Overall, I doubt the proposed research matches the benign standard that I could live with.
The second flaw is the assertion that chimps do not make particularly useful subjects for human medical research. I highly, highly doubt that to be an accurate statement. It treads into the animal rights version of science denialism, and provokes the over-reaction from people like Mark Hoofnagle who can't stand animal rights activists and miss the point that sapient species need to be treated differently.
I suspect a much better version of the utilitarian argument against using chimps for medical experiments is that they're too expensive to use, especially if you accept that we must treat them decently. To me, that would mean teaching them sign language, something you could easily argue is a necessity to avoid unnecessary harm, and should be enough to make it way too expensive to use chimps. There ought to be a law on this, and I think we could get one on a state by state basis.