On December 8, 2016, the PTAB issued six institution decisions in cases IPR2016-01127, IPR2016-01128, IPR2016-01129, IPR2016-01130, IPR2016-01131, and IPR2016-01132, agreeing to review claims of U.S. Patent Nos. 8,685,930, 8,629,111, 8,642,556, 8,633,162, 8,648,048, and 9,248,191. All six patents are owned by Allergan Inc. ("Allergan") and challenged by Mylan Pharmaceuticals Inc. ("Mylan").

The challenged claims of the six patents generally relate to methods for treating dry eye syndrome using cyclosporine components, and more specifically to a formulation containing, inter alia, 0.05% by weight cyclosporine-A ("CsA") and 1.25% by weight castor oil. These patents are listed in the Orange Book as covering RESTASIS®, Allergan's product for dry eye treatment.

Mylan relied largely on the same art in its six petitions, including a patent owned by Allergan (US Patent No. 5,474,979; "Ding") as the primary reference, as well as a couple of scientific publications and another U.S. patent as secondary references. In its institution decisions, the PTAB found that there is a reasonable likelihood that Mylan would prevail in demonstrating that challenged claims are either anticipated by Ding, or obvious over Ding in combination with one or more of the secondary references.

Regarding the anticipation challenge, Allergan acknowledged that Ding discloses various formulations having 0.05% CsA or 1.25% castor oil. It was also undisputed that the Ding discloses a preferred weight ratio of CsA to castor oil of between 0.12 and 0.02 in its formulations. Allergan argued, however, that Ding failed to specifically disclose the claimed 0.05% CsA/1.25% castor oil combination, and that the disclosed weight ratio range is "very broad." Viewing the dispute between the parties as "whether [Ding] describes the claimed amounts with sufficient specificity to anticipate this limitation of the challenged claims," and citing to the holding in Atofina v. Great Lakes Chem. Corp., 441 F.3d 991 (Fed. Cir. 2006), the PTAB framed its inquiry regarding anticipation as "whether [Ding] discloses a broad genus such that different portions of the broad range would work differently." Finding that "the current record [provides] insufficient evidence demonstrating the criticality of the claimed amounts or any difference across the range disclosed in the prior art," the PTAB sided with Mylan and granted review on the anticipation ground.

Regarding the obviousness challenge, the PTAB first concluded that Mylan has shown "a reasonable likelihood that a skilled artisan would have found it obvious to make the castor oil concentration in the emulsion [having 0.05% CsA] to reach the claimed amount of 1.25% by balancing the need to minimize any undesirable effects associated with castor oil used at an excessive concentration with the desire to take advantage of the 'substantial palliative benefits' of castor oil for the treatment of dry eye." In reaching this conclusion, the PTAB declined to adopt Allergan's proposed construction of "therapeutically effective," finding that the term's ordinary meaning and the meaning ascribed in the specification does not require a cure of a disease or disorder, as Allergen contended, but also includes either treatment or remediating of a disease or disorder.

In connection with its attempt to rebut the obviousness challenge, Allergan also pointed to the data provided in two expert declarations submitted during prosecution, arguing that the claimed formulation performed better than prior art formulations despite the expectation to the contrary. The PTAB, however, dismissed this argument by noting that neither expert had been subjected to cross-examination, and concluded that it would have been more appropriate to allow further evidence to be developed during trial.

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