A piece I found which takes a pessimistic attitude towards the possibility that the needed research and development will be possible - Curing Cancer: A Patent Impossibility :

"The FDA will not allow people in the orderly and profitable process of agonizing death by incurable cancers to try non-approved drugs. No drug company, no matter how large, can afford to spend a billion dollars and 19 years getting a non-patentable treatment through the bureaucratic minefield. There is no FDA-approved way to get there from here.

However the writer then goes on to suggest that maybe someday researchers outside the FDA orbit "perhaps in Mainland China" might get their act together. And interestingly I found this piece from a China based news service - Cheap, safe drug could be used to treat different forms of cancer.

Though of course you don't have to go to China to find places which aren't in hoc to the American FDA.

Incidentally here is a page with a rundown of the profit margins of the big drug companies