Recently, in Adello Biologics LLC v. Amgen Inc., Case PGR2019-00001 (Paper No. 13) (PTAB Apr. 19, 2019), the PTAB instituted post-grant review of claims 1-30 of U.S. Patent No. 9,856,287 (“the ’287 patent”).  The ’287 patent is the patent at issue in a pending litigation between Amgen and Apotex under the Biologics Price Competition and Innovation Act (BPCIA) in the District Court for the Southern District of Florida.  The ’287 patent, entitled “Refolding Proteins Using a Chemically Controlled Redox State,” contains claims drawn towards methods of refolding proteins expressed in non-mammalian expression systems.  Independent claims 1 and 16 require that the method include “incubating the solution so that at least about 25% of the proteins are properly refolded.”  Independent claims 10 and 26 require that “about 30-80% of the proteins are properly folded.”  Adello Biologics LLC, Apotex Inc., and Apotex Corp. (“Petitioners”) asserted eight grounds of unpatentability for lack of written description support, lack of enablement, anticipation, obviousness and indefiniteness.

In its analysis, the PTAB first determined that the ’287 patent is eligible for post-grant review. Pursuant to the AIA, post-grant review provisions only apply to patents that contain a claim with an effective filing date on or after March 16, 2013. The ’287 patent was filed on Feb. 1, 2017 but claims priority to two applications, one filed in 2009 and another filed in 2010.  Petitioners argued that claims 1-9 and 16-25 were not fully disclosed until they were added by amendment to the claims of the ’287 patent after filing and argued that claims 1-30 are not enabled.  Petitioners argued that the language “at least about 25% of the proteins are properly refolded” does not appear anywhere in the specifications or in the priority applications.  Petitioners equated “at least about 25%” with “25%-100%” and argued that the priority applications fail to provide any disclosure for any percentages of properly refolded proteins over 80%.  Amgen Inc. (“Patent Owner”) argued that the law for written description does not require explicit examples in the specification that cover the entire range of the results disclosed in the claim. The PTAB agreed but noted that “when there is substantial variation with the genus, however, a sufficient variety of species must be described to reflect the variation within the genus.” See Paper 13 at 17. The PTAB then held that the percentages of properly refolded proteins disclosed in the examples of the priority application did not constitute a representative number of species within the genus of “at least about 25%.” The PTAB held that the ’287 patent was eligible for post-grant review and that it is more likely than not that there is inadequate written description support for “at least about 25%” as recited in the claims.

Petitioners further argued that the claims fail to comply with the enablement requirement of 35 U.S.C. § 112(a). For example, Petitioners argued that the claims “recite that the thiol-pair ratio is in the range of 0.0001-100 and do not place a numerical limit on the thiol-pair buffer strength, resulting in a vast number of possible redox conditions” and that the claims do not place a limit on the proteins to be refolded. See Paper 13 at 19. Petitioner argued that due to large number of proteins covered by the claims, the specification fails to provide sufficient guidance to allow a person of ordinary skill in the art to arrive at the claimed ranges of “at least about 25%” or “about 30-80%” of the proteins being properly refolded with undue experimentation.  Patent Owner argued that the Petitioners failed to demonstrate why the experimentation needed would be undue, pointing out that the ’287 patent discloses that optimization of the redox component thiol-pair ratios and thiol-pair buffer strength can be done for each protein. The PTAB rejected these arguments. Instead, the PTAB relied on the unrebutted testimony of Petitioners’ expert who concluded that from the specification, a person of ordinary skill in the art would understand that there is no direct correlation between the thiol-pair ratio and the thiol-pair buffer strength that can be used for all proteins and as a result there is a large number of redox conditions that can tested. The PTAB agreed with the expert that the specification fails to narrow the range of these possible conditions. Thus, the PTAB concluded that it is more likely than not that claims 1-30 are unpatentable for lack of enablement.  Furthermore, in view of the Supreme Court’s recent decision in SAS Inst., Inc. v. Iancu, 138 S. Ct. 1348 (2018), because the PTAB concluded that Petitioners demonstrated more likely than not that claims 1-30 lack enablement and that claims 1-9 and 16-25 failed to provide sufficient written description support, it instituted a post-grant review of all grounds asserted in the Petition.[1]

According to the scheduling order entered with the institution decision, the Patent Owner will have until July 11, 2019 to file a response to the Petition. Subsequently, the Petitioners will have until Oct. 3, 2019 to file a reply to Patent Owner’s response.

[1] The PTAB instituted a post-grant review after its analysis of the written description and enablement grounds. However, the PTAB also made observations in its decision relating to the other asserted grounds as well.