Molecular switches provide a route around existing gene patents
June 17, 2002
By Gary Stix
Since 1980 the U.S. Patent and Trademark Office has granted patents on more than 20,000 genes or gene-related molecules. This thicket of intellectual property can make it difficult to develop biotechnologies without bumping up against patents held by others. In response, a number of companies have devised ingenious technological means of getting around such IP hurdles.
To obtain a patent, one of the things an inventor must prove is that a creation is truly novel. Genes, proteins, kidneys and all endogenous living tissue in its natural form do not meet that criterion. "A basic tenet of patent law is that you can't patent something as it is found in nature," says Kathleen Madden Williams, an attorney with the Boston law firm of Palmer and Dodge. "It has to encompass something new." The genomics gold rush revolves around genes that have been isolated and purified outside an animal, plant or microorganism. But turning on a gene to make a protein while the DNA is still lodged inside the body--or in the nucleus of a cell in a laboratory dish--would allow someone to avoid infringing a patent.
A few biotechnology companies, each using a different method, have helped partners doing research on drug candidates to switch patented genes on while in the body or a cell. Of its 25 deals with pharmaceutical and biotechnology companies, Sangamo BioSciences in Richmond, Calif., has made about a fourth of them to bypass patent restrictions by using its "zinc finger protein" transcription factors, proteins that turn genes on and off. "These collaborations were driven largely by intellectual property," says Edward O. Lanphier II, Sangamo's president and chief executive. Similarly, Athersys in Cleveland has crafted about a third of its 12 collaborations to assist partners in working around existing patents with a technique that inserts pieces of DNA into cells to turn on genes randomly and then screen for the protein of interest.
Endogenous gene activation is most lucrative if it does more than just let companies do research on drug candidates and actually serves to create close knockoffs of protein-based drugs without violating a competitor's patent. The pitfalls of this approach were highlighted in January of last year, when a federal district court in Boston ruled that Transkaryotic Therapies (TKT) in neighboring Cambridge had infringed patents of Amgen in Thousand Oaks, Calif., on an anti-anemia drug based on the protein erythropoietin (EPO). TKT had used a type of DNA gene switch to make EPO. But to administer the protein therapeutically, TKT would have had to purify the protein from the cell line in which it was produced, one of the actions that were judged to infringe Amgen patents.
Increasingly, as with Amgen's intellectual property, companies patent not only a gene but the protein made by the gene. Again, technological fixes may help. Sangamo's zinc finger protein switches, for instance, can be given directly to a patient: the zinc finger can turn on a gene that expresses a protein inside the body to alleviate a disease state--no purification step to remove the protein from a cell is required.
As for the TKT technology, not all patent estates are as extensive as
Amgen's on EPO. Last year TKT defended itself successfully against a lawsuit
that charged it with violating a patent licensed exclusively to Genzyme,
also in Cambridge, for a method of making a drug to treat Fabry's disease,
a rare fat storage disorder. Both the Amgen and the Genzyme cases have
been appealed. But no matter what the outcome, the gene-switch companies
are proving that however dense the intellectual-property thicket becomes,
someone will find a way to crawl through it if the incentives are sufficient.
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