Proving a negative is almost impossible. That's why in our courts we force the prosecution to prove you did it rather than asking you to prove that you didn't. Likewise scientists do not come foreward and say things like "this drug cures cancer, now we are gonna market and sellthe hell out of it while you guys try to prove it doesn't work". Nope,doesn't work that way. (thank God) They made the stuff. They are making the claim that it works. It is incumbent apon them to prove it does work.