Disclosure of gene from one bacterial source cannot support claims to gene from any bacterial sourceSeptember 22, 2008

In a recent decision, the Federal Circuit affirmed a district court's grant of summary judgment of non-infringement and invalidity of various claims of three patents. The district court held no genuine issue of fact existed regarding noninfringement or invalidity under the written description requirement. The patents related to DNA polymerases, and the claims at issue covered plasmids containing the gene coding region of DNA polymerase from any bacterial source. The specifications, however, only disclosed successful use of the DNA polymerase gene from E. coli. Based on this limited disclosure, the court affirmed the district court's decision that, under Regents of University of California v. Eli Lilly & Co., there was inadequate description to support the broad claims. Specifically, in order to support the broad claim, "a person of skill in the art [must] understand that the genus that is being claimed has been invented, not just a species of the genus." Here, only a single species was described, rendering the claims to DNA polymerases from any bacterial source invalid as inadequately described.More details of Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc. after the jump.Carnegie Mellon owns three patents directed to "novel recombinant plasmids for the enhanced expression of an enzyme, to the preparation by gene cloning of such plasmids, to bacterial strains containing said plasmids, [and] to methods for the conditional control of the expression of said enzyme." The patents further teach that the enzyme of interest, DNA polymerase I (Pol I), is encoded by the structural gene poIA. The patents do not disclose use of any other DNA polymerases from any other bacterial species. The claims, however, are not limited to either E. coli or to the poIA gene. The Federal Circuit quoted a representative claim from each patent (emphases added):

[C]laim 1 of the '708 patent reads as follows:1. A recombinant plasmid containing a cloned complete structural gene coding region isolated from a bacterial source for the expression of DNA polymerase I, under operable control of a conditionally controllable foreign promoter functionally linked to said structural gene coding region, said foreign promoter being functional to express said DNA polymerase I in a suitable bacterial or yeast host system.Claim 1 of the '270 patent recites:1. A recombinant plasmid providing for Nick-translation activity isolated from a bacterial source, said plasmid capable of being placed in a bacterial host system such that the host system can grow and divide.Similarly, claim 1 of the '745 patent reads:1. A recombinant plasmid containing a DNA coding sequence for the expression of DNA polymerase activity, wherein said DNA coding sequence is derived from a source that encodes a bacterial DNA Polymerase, said source not containing an amber mutation affecting expression of said DNA polymerase activity, such that when said plasmid is transformed into a bacterial host system the host system can grow and divide thereby replicating said plasmid.

The allegedly infringing product is the recombinant plasmid pLSG5, which when inserted into host cells causes the expression of the enzyme Thermus aquaticus ("Taq") DNA polymerase.The district court granted summary judgment of invalidity of the claims drafted to any bacterial source, holding that there was insufficient written description to support the broad claims. With respect to the '708 patent, the district court stated that while the claims encompass recombinant plasmids "containing a cloned complete structural gene coding region from [any] bacterial sources for the expression of DNA polymerase I", the specification described only recombinant plasmids which contained the E. coli DNA polymerase I gene region. Accordingly, the district court held that the claims did not satisfy the written description requirement. The court similarly held that the '745 patent was invalid under the written description requirement. With regard to the '270 patent, the district court stated that, under Gentry Gallery, Inc v. Berkline Corp., the '270 claims must contain "an essential feature of the invention" in order to comply with the written description requirement. The district court reasoned that because the claimed lacked the "feature of lethality", the '270 claims were invlalid. The court also granted summary judgment of noninfringement of several claims. Carnegie Mellon appealed.The Federal Circuit affirmed. The court cited Regents of University of California v. Eli Lilly & Co. for the appropriate test for satisfaction of the written description requirement with regard to biotechnological inventions. In Eli Lilly, the court stated "[a]n adequate written description of a DNA, such as the cDNA of the recombinant plasmids and microorgnisms of the claimed invention, requires a precise definition, such as by structure, formula, chemical name, or physical properties, not a mere wish or plan for obtaining the claimed chemical invention." Further, the court held "[a] description of a genus of cDNAs may be achieved by means of a recitation of a representative number of cDNAs, defined by nucleotide sequence, falling within the scope of the genus or of a recitation of structural features common to the members of the genus, which features constitute a substantial portion of the genus."Applying Eli Lilly to this case, the Federal Circuit noted the appealed claims of the '708 patent were directed towards a DNA coding sequence which is broadly defined by only its function, encoding DNA polymerase I. The court further noted that the claims encompass any bacterial species. Similarly, the '745 patent's claims are directed towards recombinant plasmids containing the DNA coding sequence which is broadly defined by only its function, encoding DNA polymerase I, and were also not limited to a single bacterial species. Under Eli Lilly, the court noted "to satisfy the written description requirement for a claimed genus, a specification must describe the claimed invention in such a way that a person of skill in the art would understand that the genus that is being claimed has been invented, not just as species of the genus."Applying this analysis to the '708 and '745 patents, the court noted that the patents:

encompass a genus of recombinant plasmids that contain coding sequences for DNA polymerase or nick-translation activity from any bacterial source, in contrast, the narrow specifications of the '708 and '745 patents only disclose the poIA gene coding sequence from one bacterial source, viz., E. coli. Significantly, the specification fails to disclose or describe the poIA gene coding sequence for any other bacterial species.

The court further observed only three out of thousands of bacterial poIA genes had been cloned as of the priority date of the applications. There was simply insufficient description to support the broad claims at issue given the inventors had only successfully used a DNA polymerase from a single bacterial source. The court accordingly upheld the district court's grant of summary judgment of invalidity of the claims from these patents.The Federal Circuit disagreed with the district court's reasoning with respect to invalidity of the '270 patent, stating the court had previously stated that it did not in announce a new "essential elements" test in Gentry Gallery and it had "applied and merely expounded upon the unremarkable proposition that a broad claim is invalid when the entirety of the specification clearly indicates that the i

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