A drug that's been around for a while, seems to work as a class attack on a number of cancers.

See this New Scientist article.

Interestingly, the author comments

"...The next step is to run clinical trials of DCA in people with cancer. These may have to be funded by charities, universities and governments: pharmaceutical companies are unlikely to pay because they can't make money on unpatented medicines. The pay-off is that if DCA does work, it will be easy to manufacture and dirt cheap."

Once again, intellectual property laws appear to be working against the interests of humanity.

The development and introduction of DCA will be an interesting case study.