From a bio perspective, it sounds like a great idea.
From a squimish perspective... it sounds like something from a horrendous distopia. I just have visions of rows of human shaped tissue cultures.
A less horrendous version could be cultured cells for each organ, with some kind of circulation between them which one could test theraputics for cytotoxicity. I've seen "labs on a chip"[0] for things like PCR, I wonder if you could do that for drug testing in vitro.