September 2, 2002
Pharmacological agriculture, the growing of crops for their proteins, has the potential to bring down the costs of certain recombinant pharmaceuticals by a factor of ten, said Andrew Baum, CEO of SemBioSys Genetics of Alberta Canada.
Baum is also head of the Biotechnology Industry Organization Joint Canada-U.S. working group on Plant Made Pharmaceuticals.
By eliminating the need for traditional bio-reactor construction he estimates this process can cut capital costs from over $ 200 million to about $ 30 million to cover such expenses as land acquisition and dedicated farm machinery. Baum also estimates that ongoing production costs can also come down from $ 200 to $ 300 a gram to around $ 25.
"Historically manufacturing was never an issue in the development of drugs," says Baum, "it used to be something you could take for granted but now it's a strategic issue you have to contemplate."
The experience of biotech, Immunex, illustrates what can go wrong. The MacKenzie quarterly estimates that the lack of manufacturing capacity for its recombinant rheumatoid arthritis drug, Enbrel, cost the company $ 200 million in lost revenue in 2001.
Baum thinks it is understandable that biotechs are in danger of getting caught in a supply crunch.
"If you have to spend a quarter of a billion dollars on a manufacturing plant before your drug is out of clinical trials you might have to hedge your bets," he said, "by not spending it all right away. But then if the product makes it and is spectacularly successful you can find yourself running out of capacity."
SemBioSys is testing a process that attaches proteins to safflower oilbodies as an oleosin fusion or through affinity capture.
Oilbodies are discrete organelles found in oil seeds where they serve as the site for triacylglyceride storage. They are comprised of a triacylglyceride core surrounded by a half- unit phospholipid membrane and an outer shell of specialized proteins known as oleosins.
With this process, separating the protein in question from the oilbody is as easy as "separating cream from milk," says Baum.
In fact SemBioSys is using dairy centrifuging equipment to collect its proteins.
Baum suspects that pharma farming may only be applicable to those proteins that do not involve glycosylation. But glycosylation is not a factor with many proteins, such as interferons and growth hormones, because they do not stick sugar molecules on protein backbones in the same way that animals do.
SemBioSys is in the process of developing bio farmed proteins for multiple sclerosis, arthritis, and psoriasis. The company expects to have its first product by 2004 and its first transgenic pharmaceutical by 2006 or 2007.
Baum cautions that just about every projection concerning large-scale bio farming at best falls into the educated guess category.
"Anybody who says that they know the answer is wrong because nobody's done it yet," he said.
© Copyright 2002 The McGraw-Hill Companies, Inc.