Use patents can be had, but I think there was some previous product with sesamin sold for weightloss. Avant is the one that first developed a true market for it and produced an affordable product.
on a side, patents are issued too easily sometimes and can be thrown out just as easy when challenged. Many of the patents issued on traditional medicinal plants are now in jeopardy. Basically, if a historical use can be found in the literature the patent can be voided. Tumeric was one of the first to be thrown out, I believe Neem and a few others have fallen as well. If its not a new use, then it is not a valid patent. I imagine several patents like this are and will be challenged soon. So if you see something like "used in ayurvedic medicine for hundreds/thousands of years... and patent pending" in the same product writeup, that patent either won't be granted.. or won't hold up when challenged.
TSC