Problems and Final ProductAs with the development of any great product, taxol also had its own share of problems. The bark of the pacific yew contained the most concentration of taxol. As a result,
many mature trees were stripped off their bark to make taxol, which killed the
trees. On top of this, each tree supplied about 2 kg of bark, which produced
only half gram of taxol, which is not even close enough to help the tens of
thousands of people with cancer. There were also many social issue regarding the killing of the yew trees to obtain taxol, which will be discussed later.
So, scientists started to try and find a way to artificially create taxol using related molecules. Finally, in 1990, Professor Robert Holton developed a way to semi-synthesize taxol from the needles of english yew trees. He isolated a relative compund, called 10-deacetylbaccatin or baccatin, from the needles of yew tree and then convert this into taxol. This was a great breakthrough since harvesting the needles of the yew tree does not have any environmental effects and is renewable. Bristol Myers Squibb (BMS), a pharmaceutical company, now produces taxol by semi-synthesis.
Another problem scientists had to overcome was the solubility issue. Taxol would not dissolve in water. In fact, it did not dissolve in many of the things researchers tried to dossolve it in. this nearly stopped the taxol project. However, they finally a solvent that could dissolve taxol and yet, still be reasonably safe for humans. It was a special elixir made of castor oil and marketed as Cremophor EL. After this discovery, scientists now moved on to the clinical trials. Taxol has been up for commercial use since 1993. So, humans have been using it for 20 years now. By 1993, the main problems relating to taxol (extracting it in large quantities fro a renewable source) had been solved. However, it was first used on humans in 1988 in USA to treat the most severe form of ovarian cancer, where it was deemed a success since 3 in every 10 patients were seeing shrinking tumors. Many test groups were even experiencing a 6 out of 10 patient improvement, a phenomenon that was never seen in ovarian cancer treatment. |