Certain compounds found in the bark of yew trees were discovered by Wall and Wani in 1967 to have efficacy as anti-cancer agents. The precursors of the chemotherapy drug paclitaxel (taxol) was later shown to be synthesized easily from extracts of the leaves of European yew, which is a much more renewable source than the bark of the Pacific yew (Taxus brevifolia) from which they were initially isolated. This ended a point of conflict in the early 1990s; many environmentalists, including Al Gore, had opposed the destructive harvesting of Pacific yew for paclitaxel cancer treatments. Docetaxel can then be obtained by semi-synthetic conversion from the precursors.
Paclitaxel is in the taxane family of medications. (PTX), sold under the brand name Taxol among others, is a chemotherapy medication used to treat a number of types of cancer. This includes ovarian cancer, breast cancer, lung cancer, Kaposi sarcoma, cervical cancer and panc cancer. It works by interference with the normal function of microtubules during cell division. It is given by injection into a vein. There is also an albumin bound formulation.
Paclitaxel was first isolated in 1971 from the Pacific Yew and approved for medical use in 1993. It is on the World Health Organisation’s List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in the developing world is about 7.06 to 13.48 USD per 100 mg vial. This amount in the United Kingdom costs the NHS about 66.85 pounds. It is now manufactured by cell culture.