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Partial Success for Institut Pasteur in Appeal Of Rejection of Genetic Engineering Patents

Thursday, January 2, 2014
By Tony Dutra

Dec. 30 --At least one genetic engineering patent owned by Paris, France-based Institut Pasteur & Universite Pierre et Marie Curie was revived from a Patent and Trademark Office rejection after a Dec. 30 ruling by the U.S. Court of Appeals for the Federal Circuit (Institut Pasteur v. Focarino, Fed. Cir., No. 2012-1485, 12/30/13).

With a focus on whether the prior art indicated “a reasonable expectation of success” and the weight of secondary indicia of nonobviousness, the court overturned a reexamination ruling of the Patent Trial and Appeal Board.

PTAB's Reexamination Hurts Pasteur.
Pasteur owns three patents (U.S. Patent Nos. 6,610,545; 6,833,252 and 7,309,605) directed to a class of enzymes called group I intron-encoded (GIIE) endonucleases that have superior specificity in genetic engineering. The patents expired in May 2012.

Precision BioSciences Inc. of Durham, N.C., requested inter partes reexamination in 2009. The PTAB agreed with an examiner's findings that prior art disclosures of GIIE endonucleases used in non-chromosomal, prokaryotic cells rendered Pasteur's invention obvious.

The board ruled that a “strong case of obviousness” was not outweighed by evidence of industry praise, copying and licensing. Pasteur appealed.


Can't Amend After Expiration.
Judge Richard G. Taranto first addressed Pasteur's contention that its attempt to amend claim 14 of the '605 patent in reexamination was not mooted by the patent's expiration. Though the amended claim text would limit the claims to chromosomal DNA, Pasteur argued that the scope of the claim would not have changed. The court disagreed, saying that the targeted DNA originally claimed was not implicitly limited to chromosomal DNA, as Pasteur contended.

“Because amending the claim to target only 'chromosomal' DNA substantively altered (narrowed) its scope, the PTO may not issue the amended claim now that the patent has expired, as stated in applicable provisions of a PTO regulation, 37 C.F.R. §1.530(j), (k),” the court said.

The court reasoned that, for inter partes reexamination, intervening rights would apply. Thus, Pasteur could not enforce the amended patent claim for past infringement, and the PTO could not extend the term of the patent to allow Pasteur to claim infringement after it expired.


No 'Reasonable Expectation of Success.'
Claims 10 and 12 of the '545 patent, however, were originally written as limited to chromosomal cells. Therefore, the question was whether a skilled artisan aware of the non-chromosomal, prokaryotic DNA focus of the prior art would have expected success with gene transfer into the chromosomal DNA of eukaryotic cells.

The court faulted the board on three counts.

First, the court said that the board erred in its factual determination that prior art references showed a GIIE endonuclease cleaving yeast chromosomes while those chromosomes were in yeast cells. Rather, to the extent a reader of those references could determine, the court said, the chromosomes had already been extracted from the yeast cells and purified.

Second, the PTAB failed to give proper consideration to disclosures in the prior art teaching away from targeting chromosomal DNA in a living cell due to warnings of toxicity, the court said. “Such a teaching counts significantly against finding a motivation to take the claimed steps with a reasonable expectation of success.”

The court noted a statement in the prior art that it would be “a great advance” to use GIIE endonucleases to make alterations in “a living animal cell.” However, the court quoted Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1352, 2008 BL 238220, 89 U.S.P.Q.2d 1161 (Fed. Cir. 2008) (209 PTD, 10/29/08), in saying that “knowledge of the goal does not render its achievement obvious,” And, it said, “obviousness generally requires that a skilled artisan have reasonably expected success in achieving that goal.”


Secondary Considerations.
Finally, the court ruled that the secondary considerations of nonobviousness put forward by Pasteur were “compelling.”

First, exclusive licensee Cellectis S.A. testified to “more than a dozen” sublicensees, including BASF Plant Science, Bayer CropScience, Biogen Idec, Monsanto and Pioneer Hi-Bred International. The court faulted the board for “too finely pars[ing] Pasteur's licensing activities” by demanding evidence that the sublicensees valued what was claimed in the '545 patent. The licensing presented “strong probative value” of what was described in the patent, the court said, and that in turn was “captured in the claims at issue.”

Second, the board's factual error in understanding the prior art disclosures also led it to err in believing industry praise was directed to what was already in the prior art, according to the court.

Third, the court said, the PTAB “stopped its analysis of Pasteur's evidence of copying prematurely.” The board said that Pasteur's listing of 20 subsequent scientific articles was insufficient unless those articles specifically referenced the methods disclosed in the '545 patent. The court said that the board should have analyzed whether “the publications' authors had access to, and borrowed from, the Pasteur sources.”

The court thus reversed the PTAB's finding of obviousness as to the two claims of the '545 patent at issue.

It vacated the obviousness judgment as to the claims of the '252 patent because they “serve as the first step to practicing the method recited by claim 12 of the '545 patent.” Though the instant decision by the court rejected the PTAB's identification of motivation to pursue the methods of the latter, the court said, “the Board has never considered whether other motivations would have made the subject matter claimed in the '252 patent obvious.”

As a final note, though, the court warned Pasteur that its evidence of secondary considerations that applied to the '545 patent “does not demonstrate that [others in the industry] licensed, praised, and copied the method because of that first step.”

Judges Raymond C. Clevenger III and Pauline Newman joined the opinion.

Thomas H. Jenkins of Finnegan, Henderson, Farabow, Garrett & Dunner LLP, Washington, D.C., represented Institut Pasteur. Michael J. Twomey of Wilmer Cutler Pickering Hale and Dorr LLP, Boston, represented Precision BioSciences. PTO Associate Solicitor Mary L. Kelly, Alexandria, Va. represented the office.

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