Drug Firm Has New Source for Tree-Based Cancer Agent

Bristol-Myers Squibb Co. said it has a new, more plentiful source for its anti-cancer agent taxol.

Taxol, which has proven effective treating ovarian and breast cancer, has until now been extracted only from the bark of Pacific yew trees.

Bristol-Myers Squibb said it has contracted with the Italian company Indena to obtain taxol from needles and twigs of yew species in Europe and Asia.

Zola Horovitz, a vice president at Bristol-Myers Squibb, said a new laboratory process helps in recovery of the substance.

The deal with Indena should help quell concern about a shortage of Pacific yew bark needed to meet the growing demand, Horovitz said.

“We are on target for producing material by the end of next year that is not from a bark source,” Horovitz said.

“It’s going to be more readily available in much larger amounts because we won’t have to worry about all the problems associated with bark collection, such as environmental concerns and all that,” he said.

The company will need far fewer Pacific yews by 1994 and in five years “we will stop using Pacific yews altogether,” Horovitz said.

The biggest concern about taxol has been supply because it takes the bark of three full-grown trees to produce enough to treat one cancer patient.

In addition, the trees thrive in the shade of the same dwindling old-growth forests where the threatened northern spotted owl lives. Lawsuits to protect the owl’s habitat have brought logging to a virtual halt on national forests in the Northwest, where most yews are found.