HRT-- Are drug companies accountable?

[background]
Hormone Replacement Therapy entails the use of prescribed drugs or natural hormones to replenish hormonal loss due to surgery or the aging process. Prempro is a drug used in this field of medicine which is specific to addressing the symptoms of menopause. This drug has recently stirred up a lot of news becuase of its suspected carcingenic nature. In response to evidence of increased cancer risk, lawfirms are flocking to file class action suits-- getting a piece of “big pharmaceutical” I suppose.
[/background]

OK, now the question… How accountable are drug companies? More specifically, at what point do we just have to take a drug on faith? Is it the responsibility of a drug company to field-test a drug over the entire lifespan of test subjects just to ensure that there are absolutely no side-effects? Will the public be willing to wait when faced with the prospect of a new and useful medication? “We found the cure for cancer, but we need to hold onto it for about 40 years just to be sure…”
Do I have the right to absolute certainty that a medication cannot harm me in any way? If it does harm me 40 years later, should I be able to sue?

(This might be a IMHO thread, but I figured I would try it here as it is a somewhat volatile issue. I’ll throw my two bits in as people post.)

Whoops, forgot my link. More information of the drug/lawsuit here.