Pharmaceutical companies are not experimenting with oral delivery, i.e., smoking, as the side effects of such delivery are more dangerous than regular cigarettes. Marinol is the best they've been able to come up with in 30 years of testing. It ain't that great. Other anti-nausea medications and pain medications are better than marinol. The research is pretty much a dead end already.
The real question is, what are people going to cope with RJ Reynolds and American Tobacco getting into the marijuana business? They thought about it at one time, but the negative publicity caused them to back off. As Washington and Colorado influence other states to perhaps pass a law legalizing it, will the tobacco companies stay out of the mix? Doubtful.