But, as I've pointed out, there's more to producing a drug than just the cost per unit. The benefits for any company that discovered a cure for cancer would still make the whole venture worthwhile even if it was cheap to produce per dose. There's more to the value of a company than just the cost of the products or services it produces. A cure would cause any companies stock price and market value to soar, and the profit potential is still there in terms of patents, licensing, etc.. But for some reason you seem to think that they'd rather forgo this and instead carry on making products which can have problematic side-effects, (on patients as well as the companies market value) etc. because they can't really be bothered and aren't that interested in making serious money.