The June 16 agreement between Cytoclonal Pharmaceutics Inc. of Dallas and Bristol-Myers Squibb moves the alternative source of the drug one step closer to possible manufacture and use, MSU officials say.
"We're not there yet," cautioned MSU-Bozeman vice president for research Bob Swenson. "But we're encouraged that the world's manufacturer and distributor of taxol has chosen this as the potential next source for the drug. We hope that this technology bears fruit."
Taxol is Bristol-Myers' brand name for paclitaxel, the drug's active ingredient that comes from the bark and needles of yew trees. Taxol is federally approved for treating breast and ovarian cancers. About one in nine women in the U.S. develops breast cancer, and about one in 70 develops ovarian cancer, according to the National Cancer Institute.
Additional studies have shown taxol's effectiveness against other diseases including esophageal cancer and the AIDS-related Kaposi's sarcoma.
"Taxol is like aspirin," British Columbia Hospital researcher Lindsay Machan told Business Week in March. "We're finding more uses for it than what it was originally intended for."
Earlier this decade, environmentalists were worried that the yew tree would be wiped out for it's meager supply of the potent drug. Scientists began looking for other sources, and in 1993 Gary Strobel at MSU-Bozeman and Andrea and Don Stierle at Montana Tech made headlines when they announced that they isolated taxol from a fungus growing on a Pacific yew tree in northwestern Montana. They named the fungus Taxomyces andreanae, after Andrea Stierle. The discovery raised the possibility of creating a renewable source of the drug by growing the fungi in vats and harvesting the taxol from them.
Lacking the resources to develop and possibly commercialize taxol-making fungi, MSU licensed the technology to Cytoclonal Pharmaceutics, a biopharmaceutical company that specializes in cancer therapies.
Cytoclonal began working to increase yields while Strobel sampled yew trees around the world for more of the miniature taxol factories. MSU also applied for a patent on the technology, which was awarded initially in 1994 and expanded last year.
In addition, Cytoclonal Pharmaceutics licensed a gene from Washington State University that controls taxol production in the yew tree and incorporated the gene into research on the MSU fungi. That technology is also part of the agreement between Cytoclonal Pharmaceutics and Bristol-Myers Squibb.
This agreement, finalized June 16, is a sublicense between Cytoclonal Pharmaceutics Inc. and Bristol-Myers that will further develop microbial fermentation of taxol, which is the way penicillin and other antibiotics are made.
"Bristol-Myers has one of the best fermentation capabilities anywhere in the world," said MSU's intellectual property officer Becky Mahurin.
One of the world's largest drug manufacturers, Bristol-Myers Squibb reported $17 billion in sales in 1997. Taxol is the company's second-largest product, reaping almost $941 million in sales worldwide last year, according to Forbes Magazine. The cost of taxol ranges between $1,000 and $2,000 a treatment.
The drug was never patented, however, so the fact that MSU was awarded broad patent coverage for microbial fermentation of taxol no doubt interested the company, said Mahurin.
"This could potentially be the only non-yew source of the drug," she said. Meanwhile, Strobel will continue his hunt for other medically useful fungi, and under the terms of Tuesday's agreement, Cytoclonal Pharmaceutics and Bristol-Myers Squibb will screen those organisms to see what bioactive compounds they yield.
Funding for the Montana taxol research has came from the Montana Science and Technology Alliance, the American Cancer Society, the National Science Foundation, the Montana Agricultural Experiment Station, MSU, Montana Tech, the National Cancer Institute and Cytoclonal Pharmaceutics.