Dec. 25, 2005
Christmas Trees to Provide Key Tamiflu Ingredient
By Leonard Zehr
Toronto Globe and Mail
Your used Christmas tree might save you from a bird flu pandemic.
As governments around the world scramble to stockpile the antiviral Tamiflu,
generic drug maker Biolyse Pharma Corp. plans to begin next month making
shikimic acid, the main ingredient in the manufacture of oseltamivir,
commonly known as Tamiflu, from the needles of discarded Christmas trees.
Tamiflu, as almost everybody knows by now, treats seasonal influenza and is
also being championed as a first line of defense against a possible pandemic
outbreak of bird flu, which has been devastating chicken populations across
Southeast Asia and parts of Europe.
So far, the H5N1 virus, which usually strikes people in close contact with
diseased fowl or their droppings, has infected an estimated 130 people,
killing 70. The worry is that H5N1 will undergo a genetic mutation with a
human seasonal influenza virus, morphing into a deadly strain that could
jump between people like the common cold.
After being rejected as a Tamiflu supplier by Swiss drug maker F.
Hoffmann-La Roche Ltd., which has a monopoly grip on the manufacture of the
drug, Biolyse turned its sights to making shikimik acid.
The reason: the price of shikimik acid has soared to more than $500 a
kilogram from $45 in the past 12 months on shortages of Tamiflu and
skyrocketing demand.
Biolyse specializes in extracting chemicals from plants and biomaterials at
its plant in St. Catharines, Ontario, and now makes a generic version of the
cancer drug paclitaxel from yew trees.
"Our research has shown that 2-to-3 percent of the biomass from various
pine, spruce and fir trees is extractible shikimic acid," Biolyse principal
Claude Mercure said.
As the process moves to the commercial stage from the laboratory, he said
the company is aiming to eventually produce one-to-three tons of shikimic
acid a month.
To get started, next month it will receive some 500,000 Christmas trees to
be donated by Toronto-based Gro-Bark, a forestry recycling company.
Most shikimic acid is now extracted from star anise, the fruit of a
slow-growing evergreen in China, which is harvested for several months each
year. That's why Roche's production of Tamiflu takes about 12 months and
there isn't nearly enough of the drug to go around for government
stockpiling.
"What makes our process more viable is the fact that the particular species
of pine, spruce and fir that we are working with are far more abundant than
the seedlings of star anise," said John Fulton, Biolyse's vice-president for
new product development.
Mercure said Biolyse has no plans to make Tamiflu unless Ottawa grants
compulsory licenses under the Patent Act in a national emergency. In such a
case, he said the company could produce the drug in five weeks.
In countries where Roche's patents on Tamiflu aren't recognized, like the
Philippines and Thailand, he said Biolyse is in discussions to sell shikimic
acid and provide technical assistance so the drug can be manufactured for
use in that country.
Distributed by Scripps Howard News Service, http://www.shns.com