Since the 1960's the CSIR (the Council for Scientific and Industrial Research in South Africa) have been testing their indigenous plants to discover which may have value they can develop.
It was at the start of this process, in the 60's that the CSIR, knowing that tribes people were using Hoodia to stave off hunger pangs, started investigating it. Feeding Hoodia to cows in a controlled environment they saw that the cows started to lose their appetite.
Realizing that this could have enormous value to the pharmaceutical industry, they started a long 30 year study to discover how Hoodia works.
Then, in the 1990's once the CSIR had identified the specific molecules of Hoodia that made it act as an appetite suppressant, they acquired patents Worldwide.
Note: the CSIR have patented use of the extract of the active molecule in Hoodia, and NOT the Hoodia Gordonii itself. You cannot patent a naturally growing plant.
While the CSIR could congratulate themselves, they lacked funds to further develop their Hoodia extract.
The solution was to lease the extract patent to a UK company called Phytopharm. It was indeed Phytopharm who gave the name to the Hoodia Gordonii active molecule P57 (it was their 57th project).
Phytopharm in partnership with initially Pfizer and now Unilever, have spent over $20 million dollars to researching and conducting clinical trials on Hoodia. It is Unilever who now co-lease the patent and are aiming to release products containing Hoodia extract from late 2009.
Note: While Phytopharm, Unilever and the CSIR own/share the patent for the Hoodia extract - it is perfectly legal for other companies to sell powdered Hoodia as a herbal product.