I'd say that's an unfair, and loaded statement to make. "Bought up" is a very loaded term, and suggests bribery and denial of the thing being bought up from the "not-rich" by virtue of it all being taken by the "rich".
So, you say there is a "pattern", and that this is somehow the purposeful doing of the rich. With not any proof of wrong-doing, you jump to that conclusion. You don't even posit that maybe it's perhaps researchers go where there is funding, or maybe drug companies find it more profitable to treat diseases that affect the rich, whatever.
No. You blame the rich, for essentially having money and spending it on the things that affect them(if we can even make that causal link, but it's more likely indirect as per my alternate suggestions above). So in essence, what you're really bothered by is the fact that the rich don't share your views on what the rich should be spending their money on.