PATENTS - Pfizer v. Teva

Pfizer Inc. v. Teva Pharm. USA, Inc., 2012-1576, 2014 WL 463757 (Fed. Cir. Feb. 6, 2014)

Regrading 112 enablement: 

In view of the finding that enantiomer separation methods are well-known and routine to a person of ordinary skill, we agree with the district court that the inventors were not required to provide a detailed recipe for preparing every conceivable permutation of the compound they invented to be entitled to a claim covering that compound. Where a claim has been construed to cover a chemical compound, the specification is not deficient merely because it does not disclose how to prepare a particular form or mixture—among hundreds of possible permutations—of that compound. See In re Hogan, 559 F.2d 595, 606 (CCPA 1977) (noting that requiring such specific disclosures would “impose an impossible burden on inventors”).

Instead, claim 2 satisfies the requirements under § 112(a) because the ′692 application's disclosure, coupled with the methods for synthesis and resolution that were found to be well-known and routine in the art, is sufficiently enabling. The district court's legal determination of enablement was not incorrect. Its factual findings are not clearly erroneous. We therefore affirm the determination that claim 2 is not invalid for lack of enablement.

Regarding 112 written description:

But written description does not require inventors, at the time of their application for a patent, to reduce to practice and be in physical possession of every species (e.g., the S-enantiomer of 3–isobutylGABA) of a genus (3–isobutylGABA) claim. For claims to a chemical compound, an application satisfies the written description requirement when it details “relevant identifying characteristics” such that the compound can be distinguished from other compounds. In re Wallach, 378 F.3d 1330, 1333, 1335 (Fed.Cir.2004). 

Here, the ′692 application not only disclosed the structure of 3–isobutylGABA as the preferred embodiment of the invention, see J.A. 3018–19, 20764:11–14, 3011, but also set forth in vitro and in vivo data for the compound, J.A. 3025–29, 20766:19–21, and described a method of synthesizing the compound, J.A. 3012–14, 20900.

As the district court correctly found, such a description is sufficient for persons of ordinary skill in the art to recognize that the inventor invented what is claimed. Union Oil Co. of Cal. v. Atl. Richfield Co., 208 F.3d 989, 997 (Fed.Cir.2000)

Regarding 103 obviousness:

On the selection of a lead compound, the district court found that the Appellants “did not point to any evidence in the prior art indicating that a particular compound or class of compounds, including alkyl-substituted GABA analogs ... would improve anti-seizure treatment.”District Court Opinion, at 667. We agree that the record contains scant evidence that either gabapentin or 3–isopropylGABA would have been selected as a lead compound.

With respect to gabapentin, no evidence in the record firmly situates gabapentin in the prior art or otherwise supports its selection as a lead compound. At most, Appellants established that gabapentin was being tested for its anticonvulsant effect contemporaneously with 3–isobutylGABA, see J.A. 20849, but there is no testimony establishing its being tested prior to the discovery of 3–isobutylGABA. Appellants note that Appellees' expert admitted that by 1990, gabapentin had entered Phase III clinical trials, see J.A. 20982–83, but no testimony indicates that the trials or results therefrom had been disclosed publicly by then.

Further, there is no evidence in the record of motivation for a skilled artisan to modify gabapentin for further anticonvulsant research. Appellees submit that Appellants have failed to provide the most basic details about gabapentin, such as a discussion of its advantages over other compounds, biological or other data, or mechanism of action—any of which would have aided the selection analysis.

Instead, Appellants chose to emphasize that gabapentin was a solid choice for a skilled artisan based on its structural similarity to pregabalin, a fact the specification of the ′819 patent acknowledged. See ′ 819 patent col. 13 ll. 12–16. A patent challenger, however, must demonstrate the selection of a lead compound based on its “promising useful properties,” not a hindsight-driven search for structurally similar compounds.Daichii, 619 F.3d at 1354. 

[...]

According to Appellants, the disclosures in Fish, Shashoua, and Colonge would have taught a skilled artisan to modify “lower alkyl substitutes”—which includes isobutyl—at GABA's 3–position to achieve 3–isobutylGABA. However, it is quite evident that the Fish, Shashoua, and Colonge references together disclosed trillions of compounds without calling out alkyl groups in particular or singling out isobutyl specifically. 

As the district court correctly found, the Appellants “did not point to any evidence in the prior art indicating that a particular compound or class of compounds” nor “identify any teachings as of the filing date that would have directed a skilled artisan to substitute [at GABA's 3–position] with an isobutyl group, as opposed to any other alkyl group [.]” District Court Opinion, at 667. Indeed, a vague suggestion in the prior art pointing to a broad class of compounds, without any teaching particularly identifying isobutyl among the millions of potential compounds, is not a teaching of “specific molecular modifications” required by our precedent. Takeda, 492 F.3d at 1356. Finally, the district court found Appellees to have credibly established that anticonvulsant drug discovery in 1990 was “complicated,” “unpredictable,” and “largely conducted through trial and error.” District Court Opinion, at 667.

This finding would have precluded any argument by Appellants that there would have been a “reasonable expectation of success” to achieve an anticonvulsant in 3–isobutylGABA even if Appellants were able to establish that the prior art taught the substitution of isobutyl at GABA's 3–position. 

[Emphasis added.]