|Shane Ashford, sophomore
Texas Woman's University
Denton, TX 76201
November 8, 1999
ON THE HISTORY OF TAXOL
During the 1960's, the National Cancer Institute (NCI) began a search for plants with an effect on chemotherapy
for cancer. The process was very time consuming and many plant extracts underwent random screening. Finally, the
hard work paid off and taxol was discovered. This wonder drug was produced from the bark of the Pacific yew tree,
Taxus brevifolia, from which the name taxol was derived. Although the drug was discovered forty years ago, it was
not tested experimentally until 1977. It took another sixteen years to be approved by the Food and Drug Administration
(FDA) for the treatment of ovarian cancer, breast cancer, and Kaposi's sarcoma.
In 1963, the U.S. Forest service collected the Pacific yew tree bark and shipped it to the NCI for study. Dr. Monroe
Wall and Dr. Mansukh Wani isolated the Pacific yew tree compound and noted its antitumor activity in a broad range
of rodent tumors. Then identified the active ingredient in the Pacific yew tree to be the seventeenth isolated
compound, called paclitaxel (taxol). Later, problems with extracting, processing and neutral activity of paclitaxel
suspended the research. Paclitaxel had a unique ability to prevent cell division by pulling apart the microtubules
which rearrange throughout the life of a cell (Susan Horowitz at Albert Einstein College of Medicine, New York,
1979). This ability allowed for certain cancer patients to extend their lives up to fifty percent of the expected
life sentence that they were given at the onset of the disease.
The NCI began to sponsor three phases to the research of paclitaxel against a number of different types of cancer,
as studies of paclitaxel used by Dr. Moore, Dr. Wani, and Dr. Horowitz progressed. The first phase was to test
the amount of the drug a person could withstand. Unfortunately, the first phase was not successful because allergic
reactions caused by taxol in some patients. This situation made the NCI delay and even discontinue some aspects
of the research. Later on it was discovered that the solvent used for the delivery of taxol was the ingredient
causing the allergic reactions and not taxol itself.
During phase two, scientists at Johns Hopkins Oncology Center in Columbia, Maryland reported a thirty percent response
rate in patients recieving paclitaxel with advanced ovarian cancer. Still, by this point, the difficulties in producing
the drug hindered the scientists in testing more patients. The inability to produce enough drug caused phase three
of the research to be triggered earlier. Also, at this point the NCI invited pharmaceutical companies to be involved
in the development of paclitaxel. Bristol-Myers Squibb in New York was chosen by the NCI to be a partner in the
development of TaxolTM (paclitaxel). Bristol-Myers Squibb commited to make taxol their top priority.
Finally, by 1992, the FDA approved taxol to be used in patients for whom the first-line treatment of carcinoma
of the ovary failed. In under two years Bristol-Myers Squibb had resolved supply, purity, and production problems
of taxol and were distributing enough drug for all patients in need. Eventually, they gained clearance from the
FDA for treatment of breast cancer after failure of combination chemotherapy. The new semisynthetic form of taxol
manufactured form renewable sources made it a lot faster and easier for Bristol-Myers Squibb to produce and market
it for those needy patients. Then in 1997, the FDA approved Taxol for the second-line treatment of AIDS related
Taxol has overcome many odds to be where it is at today. It takes a lot of time, effort, and money to create a
new drug for humans to use against the latest life threatening diseases. In fact, it took us about forty years
to find out this much about taxol; we still do not know all there is to know about this drug. The entire process
of developing a new drug is estimated to take no less than twelve years with a cost of $250-300 million. There
may be ten thousand potential drugs screened and only about twenty proceed to animal testing. In stage two out
of these twenty, only ten get used in clinical trials on humans and in stage three only one gains approval from
In the end, taxol was a successful journey, even though there were many obstacles in the way of its success. The
drug has helped to make many patients happier on their road of life. Today, taxol is being tested for first-line
treatment of ovarian cancer which could lead to many lives being saved. There is also the chance of taxol being
used in the treatment for non-small cell lung cancer, one of the most deadly diseases among smokers. So, finally
when we as humans went back to nature, it paid off. Natures goodness was always there; all we had to do was look
"Fact Sheet: RTI's Discovery of Taxol." Research Triangle Institute. Online. 1999.
"Taxol." Physicians Desk Reference, 53rd ed, Medical Economics Company Inc., New Jersey, 1999.
Trankina, Michelle. "Drugs That Grow On Trees." The World & I, The Washington Times, Washington D.C.,
Aug. 1998: 158.