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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`APOTEX CORP.
`APOTEX, INC.
`Petitioner
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`v.
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`ALLERGAN, INC.
`Patent Owner
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`Case IPR2015-01278
`Patent 8,633,162
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`PATENT OWNER ALLERGAN, INC.’S
`PRELIMINARY RESPONSE
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`Case IPR2015-01278
`Attorney Docket No: 13351-0060IP1
`TABLE OF CONTENTS
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`1.
`2.
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`3.
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`I.
`II.
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`INTRODUCTION ................................................................................ 1
`BACKGROUND OF THE ‘162 PATENT .......................................... 7
`A. Dry Eye Disease is a Serious Disease ........................................ 7
`Palliative Treatments Only Alleviate the Symptoms of Dry Eye
`B.
`Disease ....................................................................................... 7
`C. Allergan’s Development of RESTASIS® ................................. 8
`III. THE ‘162 PATENT .............................................................................. 9
`It was counterintuitive to combine 0.05% cyclosporin with a
`A.
`vehicle containing 1.25% castor oil ......................................... 10
`Castor oil is cytotoxic and an irritant ....................................... 10
`Increasing the amount of castor oil in the emulsion would be
`expected to reduce the thermodynamic activity of the emulsion
` .................................................................................................. 12
`PK data predicted 0.05% cyclosporin/1.25% castor oil would be
`less effective than 0.05% cyclosporin/0.625% castor oil and
`0.1% cyclosporin/1.25% castor oil .......................................... 14
`B. During prosecution the Examiner agreed that the performance
`of the claimed emulsion relative to the Ding ‘979 patent was
`unexpected ................................................................................ 18
`IV. ARGUMENT...................................................................................... 20
`A. An emulsion that is “effective in treating dry eye disease” or
`therapeutically effective” must treat the underlying disease ... 21
`Claims 1-10, 12-14, 16-20. and 22-24 would not have been
`obvious over Ding ‘607/Ding ‘979 plus Sall ........................... 24
`The inventors proceeded contrary to the teachings of the prior
`art and developed an emulsion that has surprising therapeutic
`efficacy against dry eye disease ............................................... 25
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`B.
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`1.
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`Case IPR2015-01278
`Attorney Docket No: 13351-0060IP1
`There was no reasonable expectation that increasing castor oil
`concentration would increase therapeutic efficacy .................. 29
`The differences between the claimed emulsion and the Ding
`‘979 emulsions are differences in kind, not degree ................. 33
`Allergan did not admit that the claims were unpatentable ....... 34
`Claims 11 and 21 would not have been obvious over Ding
`‘607/Ding ‘979 plus Sall plus Acheampong ............................ 36
`Claim 15 would not have been obvious over Ding ‘607/Ding
`‘979 plus Sall plus Glonek ....................................................... 36
`CONCLUSION .................................................................................. 36
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`4.
`C.
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`D.
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`2.
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`3.
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`ii
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`V.
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`Case IPR2015-01278
`Attorney Docket No: 13351-0060IP1
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`LIST OF EXHIBITS
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`EX. 2002
`EX. 2003
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`Exhibit No. Description
`EX. 2001
`NDA 21-023 Cyclosporine Ophthalmic Emulsion 0.05%, Original
`NDA Filing, Vol. 1 (Feb. 24, 1999)
`U.S. Pat. No. 4,839,342
`Said et al., Investigative Opthamology & Visual Science, vol. 48,
`No. 11 (Nov. 2007):5000-5006
`Alba et al., Folia Ophthalmol. Jpn. 40:902-908 (1989)
`Stedman’s Medical Dictionary, definition of therapeutic
`Dorland’s Illustrated Medical Dictionary, definition of therapeutic
`Stedman’s Medical Dictionary, definition of palliative
`Excerpts from the prosecution history of U.S.S.N. 13/967,979
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`EX. 2004
`EX. 2005
`EX. 2006
`EX. 2007
`EX. 2008
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`Case IPR2015-01278
`Attorney Docket No: 13351-0060IP1
`TABLE OF AUTHORITIES
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` Page(s)
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`Cases
`Allergan, Inc. v. Sandoz Inc.,
`No. 2014-1275, slip op. (Fed. Cir. Aug. 4, 2015) ............................ passim
`
`Arkie Lures, Inc. v. Gene Larew Tackle, Inc.,
`119 F.3d 953 (Fed. Cir. 1997) ................................................................. 32
`
`In re Cuozzo Speed Techs., LLC,
`No. 2014-1301, slip op. (Fed. Cir. 2015) ................................................ 21
`
`In re Cyclobenzaprine Hydrochloride Extended-Release
`Capsule Patent Litig.,
`676 F.3d 1063 (Fed. Cir. 2012) ............................................................... 29
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`Galderma Laboratories L.P. v. Tolmar, Inc.,
`737 F.3d 731 (Fed. Cir. 2013) ........................................................... 25, 33
`
`In re Translogic Tech., Inc.,
`504 F.3d 1249 (Fed. Cir. 2007) ............................................................... 21
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`Other Authorities
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`37 CFR § 42.100(b). ..................................................................................... 21
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`37 CFR §§ 42.6(e)(4) and 42.205(b) ............................................................ 38
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`Case IPR2015-01278
`Attorney Docket No: 13351-0060IP1
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`I.
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`INTRODUCTION
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`U.S. Patent No. 8,633,162 (“the ‘162 patent”) covers the use of Allergan’s
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`RESTASIS® medication for treating a serious eye condition known as
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`keratoconjunctivitis sicca (“KCS”), more commonly known as dry eye disease.
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`Allergan has 4 other Orange Book-listed patents that cover RESTASIS® and its
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`use, each of which is the subject of an IPR petition that Apotex filed.1
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`RESTASIS® is the only prescription medication indicated for treating the
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`underlying disease itself, as opposed to relieving symptoms of the disease. See
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`EX. 1043 (RESTASIS® label), p. 1; EX. 1004 (Sall), p. 8 (“[T]here is currently no
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`therapeutic treatment for dry eye disease. The only treatments available are
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`palliative in nature and provide insufficient relief for many patients”).
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`RESTASIS® is a therapeutic emulsion that contains 0.05% by weight cyclosporin
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`A in a liquid vehicle that includes 1.25% by weight castor oil, polysorbate 80, and
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`other excipients. EX. 1043, pp. 3-4; EX. 2001, p. 256. Cyclosporin is an
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`immunosuppressant that, when delivered to the eye, suppresses the inflammatory
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`processes underlying dry eye disease. EX. 1004 (Sall), pp. 1-2. The distinction
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`between treating the disease itself—i.e., therapeutic treatment—versus merely
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`relieving symptoms is key for purposes of this IPR proceeding.
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`1 The other 4 patents are U.S. 8,629,111; U.S. 8,642,556; U.S. 8,648,048; and U.S.
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`8,685,930.
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`Case IPR2015-01278
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`Although Apotex refers to the “therapeutic effect” of castor oil in the
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`petition, see, e.g., Petition at pp. 8-9, castor oil has no therapeutic effect because it
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`does not treat the disease itself. Cyclosporin is the only therapeutic agent present
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`in RESTASIS®. However, because cyclosporin has limited solubility in water, it
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`is necessary to combine it with a lipophilic material, such as castor oil, in a vehicle
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`to deliver it to the eye. See EX. 1003 (Ding ‘979), 1:40-53.
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`Castor oil was known to irritate the sensitive tissues of the eye and the
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`conventional teaching was to limit its use in ophthalmic formulations. See, e.g.,
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`id., 3:43-48. Allergan’s prior art Ding ‘979 patent, however, disclosed that
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`combining castor oil with an emulsifier and dispersing agent such as polysorbate
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`80, along with other excipients, could reduce the irritation potential of an emulsion
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`vehicle using castor oil. Id., 3:49-53. When cyclosporin was added to a vehicle
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`formulated in this way, the resulting composition exhibited reasonably high
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`thermodynamic activity, and avoided the cyclosporin crystallizing and
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`precipitating out of the vehicle. Id., 1:25-28. But even in these emulsions, the
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`castor oil remains a component in the vehicle used to deliver the therapeutic
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`agent—the cyclosporin—to tissues of the eye.
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` The claims of the ‘162 patent recite the specific combination of 0.05%
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`cyclosporin/1.25% castor oil/polysorbate 80 found in RESTASIS®. This
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`particular combination is unique and has unexpected therapeutic effect against dry
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`eye disease relative to emulsions containing 0.05% cyclosporin/0.625% castor
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`oil/polysorbate 80 and 0.1% cyclosporin/1.25% castor oil/polysorbate 80. The
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`latter two emulsions are disclosed in Allergan’s Ding ‘979 patent (EX. 1003, 4:30-
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`45, Example 2, compositions D and E), over which the Examiner rejected the
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`claims during the original prosecution of the ‘162 patent.
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`The Ding ‘979 patent is the closest prior art to the ‘162 patent. During
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`prosecution of the ‘162 patent, Allergan presented the results of pharmacokinetic
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`(“PK”) experiments comparing the claimed emulsion to the two emulsions
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`disclosed in the Ding ‘979 patent. EX. 2008, pp. 18-80 (Response to Office Action
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`dated 10/11/13; Declaration of Dr. Rhett Schiffman, pp. 36-61, ¶¶ 9-20;
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`Declaration of Dr. Mayssa Attar, pp. 62-80, ¶¶ 6-14). The PK experiments
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`predicted that on the basis of bioavailability, the claimed emulsion would have
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`been less effective than the two emulsions disclosed in the Ding ‘979 patent. Id.
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`Surprisingly, however, the claimed emulsion was more effective than the
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`0.05%/0.625%/1.00% emulsion and at least as effective as the 0.1%/1.25%/1.00%
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`emulsion. Id.
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`The claimed emulsion cut the amount of cyclosporin in half without loss of
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`efficacy. This feature is particularly advantageous because cyclosporin has been
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`known to cause serious liver and kidney damage. See EX. 2002, 3:59-66.
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`Moreover, it was achieved by doubling the amount of castor oil relative to the
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`composition in the Ding ‘979 patent that contained 0.05% cyclosporin, a choice
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`that was counterintuitive given that castor oil was cytotoxic and known to irritate
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`patients’ eyes. See, e.g., EX. 2003 (Said et al.), p. 1 (“Castor oil is the commonly
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`used lipophilic vector but has been shown to be cytotoxic”); EX. 2004 (Alba et al.),
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`p. 7 (describing “significant corneal edema” associated with castor oil when used
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`as a vehicle for cyclosporin).
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`The natural inclination of a person of skill in the art would have been to use
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`the minimum amount of castor oil necessary to dissolve the cyclosporin. In the
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`case of 0.05% cyclosporin, that amount would have been no greater than the
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`0.625% amount of castor oil that the Ding ‘979 patent used and described as
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`reducing the irritation associated with the cyclosporin while maintaining
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`reasonably high thermodynamic activity. Using more castor oil would be expected
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`to possibly increase irritation and reduce thermodynamic activity.
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` The Examiner allowed the claims over the Ding ‘979 patent on the basis of
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`these surprising results. EX. 2008, pp. 13-15. Apotex now asks the Board to re-
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`visit the patentability of the ‘162 patent claims over the very same Ding ‘979
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`patent.2 However, Apotex offers no credible evidence to rebut the surprising
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`2 The petition actually alleges unpatentability based upon the Ding ‘607 patent
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`incorporating the Ding ‘979 patent by reference. However, for the reasons
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`Attorney Docket No: 13351-0060IP1
`results on which the Examiner relied when she allowed the claims. In fact, one of
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`Apotex’s own experts, Dr. Ta, agrees that the PK data Allergan presented to the
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`Examiner predicts that both of the emulsions disclosed in the Ding ‘979 patent
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`would have been more effective than the claimed emulsion. See EX. 1007 (Ta
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`Decl’n), ¶¶ 56-57.
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`Apotex wrongly argues that any improvement is due to the “therapeutic”
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`effect of castor oil, and that increasing the amount of castor oil would have been
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`beneficial by increasing the residence time of the emulsion on the surface of the
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`eye. See EX. 1005 (Xia Decl’n), ¶¶ 114, 245, and 253; EX. 1007 (Ta Decl’n), ¶¶
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`48, 55, and 57; Petition, pp. 8-9. Apotex further alleges that the Sall paper (EX.
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`1004) would have motivated a person of ordinary skill to combine 0.05%
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`cyclosporin with 1.25% castor oil. See EX. 1005 (Xia Decl’n), ¶¶ 115 and 240-
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`243; EX. 1007 (Ta Decl’n), ¶¶ 36-38; Petition, pp. 50-52. But castor oil has no
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`therapeutic effect on dry eye disease. Cyclosporin is responsible for the
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`therapeutic effect and must be delivered from the lipophilic vehicle into the
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`ophthalmic tissue. Increasing the residence time of the emulsion on the eye will
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`not improve delivery if, based upon thermodynamic principles, the lipophilic
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`cyclosporin remains dissolved in the lipophilic castor oil carrier. See EX. 1005
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`discussed in this response, there is no meaningful difference between the proposed
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`combination of Ding patents versus the Ding ‘979 patent alone.
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`(Xia Decl’n), ¶ 117 (noting that because cyclosporin is lipophilic, it prefers to
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`remain dissolved in the castor oil carrier).
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`Sall concludes that emulsions containing both 0.05% and 0.1% cyclosporin
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`were “safe and effective.” EX. 1004 (Sall), p. 1. However, Sall does not disclose
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`the amount of castor oil, polysborbate 80, and other excipients in each
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`“proprietary” vehicle. This omission, which Apotex ignores, is critical. The PK
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`data that the Examiner considered during prosecution predicted that emulsions
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`with 0.05% cyclosporin/0.625% castor oil would be more effective than emulsions
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`with 0.05% cyclosporin/1.25% castor oil. Moreover, as noted above, castor oil
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`was known to be cytotoxic and irritating. Both points are consistent with the Ding
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`‘979 patent, where the only example of an emulsion with 0.05% cyclosporin
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`included 0.625% castor oil. Therefore, a person of ordinary skill reading Sall
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`logically would have used 0.05% cyclosporin with 0.625% castor oil—not 1.25%.
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`The inventors’ decision to use 1.25% castor oil was counterintuitive and produced
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`an emulsion that was surprisingly effective.
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` Apotex’s petition merely recycles references and grounds raised during the
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`original prosecution, but offers no credible new evidence that would compel a
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`different conclusion. Apotex’s petition, therefore, fails to establish a reasonable
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`likelihood that at least one claim of the ’162 patent is unpatentable. Accordingly,
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`Allergan requests that the Board deny the petition.
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`II. BACKGROUND OF THE ‘162 PATENT
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`A. Dry Eye Disease is a Serious Disease
`Dry eye disease, or KCS, is a serious ocular disease that afflicts millions of
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`patients. Indeed, it is one of the most common patient complaints treated by
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`ophthalmologists. It is estimated that it affects millions of people worldwide. EX.
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`1004 (Sall), pp. 1-2; EX. 1023 (Stevenson), pp. 2-3. Dry eye disease is not simply
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`occasionally feeling eye dryness; it is a serious condition that can substantially
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`impact the quality of life in patients who have it. Patients who suffer from dry eye
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`disease generally experience symptoms such as ocular discomfort, which can
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`include a dry, gritty feeling in the eye and foreign body sensation; burning;
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`irritation; photophobia; and blurred vision. Id. Severe dry eye disease can also
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`lead to an inability to produce tears and an increased risk of ocular surface damage
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`and ocular infection. Id.
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`B.
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`Palliative Treatments Only Alleviate the Symptoms of Dry Eye
`Disease
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`Dry eye disease is the result of an underlying inflammatory process.
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`Conventional medications for dry eye disease, though, do not affect these
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`underlying processes, and thus do not treat dry eye. Rather, they merely provide
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`palliative relief in the form of tear replacement or eye lubrication. EX. 1004 (Sall),
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`pp. 1-2; EX. 1023 (Stevenson), pp. 2-3.
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`Prior to the filing date of the ‘162 patent, a number of palliative treatments
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`for dry eye were known. Examples included artificial tear formulations, punctal
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`plugs, and topical steroids. EX. 1020, pp. 2-3. Emulsions comprising admixtures
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`of polysorbate 80 and oils such as castor oil, corn oil, sunflower oil, and light
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`mineral oil were also known to provide palliative relief. EX. 1002 (Ding ‘607),
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`3:41-48. For example, the Ding ‘607 patent describes the ability of these
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`emulsions, when applied to the surface of the eye, to form a film that remained in
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`place and “retard[ed] water evaporation from the eye which alleviates dry eye
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`symptoms.” Id., 3:66 to 4:3. As the Ding ‘607 patent notes, these treatments were
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`palliative—they alleviated dry eye symptoms, but did not treat the disease itself.
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`C.
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`Allergan’s Development of RESTASIS®
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`RESTASIS® is formulated as an emulsion of 0.05% by weight cyclosporin
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`A, 1.25% by weight castor oil, and 1% polysorbate 80, along with other excipients.
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`EX. 1043, pp. 3-4; EX. 2001, p. 256. RESTASIS® is different from any other
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`drug prescribed for dry eye disease. Its active ingredient, cyclosporin A, is a drug
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`with immunomodulatory and anti-inflammatory properties. EX. 1004 (Sall), pp. 1-
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`2. Unlike other dry eye medications—which relieve the symptoms of dry eye
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`disease, but do not treat it—RESTASIS® actually affects the underlying processes
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`that are thought to lead to dry eye disease. In other words, it treats the disease
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`rather than just relieving the symptoms. See EX. 1043, p. 1.
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`In late 2002, FDA approved RESTASIS®, the first prescription ophthalmic
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`emulsion ever approved, “to increase tear production in patients whose tear
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`production is presumed to be suppressed due to ocular inflammation associated
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`with keratoconjunctivitis sicca.” EX. 1043, p. 1. RESTASIS® remains the only
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`product approved by FDA that increases the eye’s production of natural tears, even
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`12 years after its original approval and despite a substantial commercial incentive
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`for developing dry eye treatments. See id.
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`III. THE ‘162 PATENT
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`The ‘162 patent is one of several patents covering Allergan’s RESTASIS®
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`medication and its use to treat conditions such as dry eye disease. It contains 24
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`claims, each directed towards a method of treating dry eye disease by
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`administering to a patient’s eye an ophthalmic emulsion that includes 0.05% by
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`weight cyclosporin A, 1.25% by weight castor oil, and polysorbate 80. Claim 1 is
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`representative. It recites:
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`1. A method of treating dry eye disease, the method comprising
`topically administering to the eye of a human in need thereof an
`emulsion at a frequency of twice a day, wherein the emulsion
`comprises cyclosporin A in an amount of about 0.05% by weight,
`polysorbate 80, acrylate/C10-30 alkyl acrylate cross-polymer, water,
`and castor oil in an amount of about 1.25% by weight,
`wherein the topical ophthalmic emulsion is effective in treating
`dry eye disease.
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`Claim 1 sets forth the formulation of RESTASIS® and its FDA-approved
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`use for treating dry eye disease. Independent claim 23 similarly recites treating dry
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`eye disease with the aforementioned emulsion. Independent claim 18 recites
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`reducing side effects in a human being treated for dry eye syndrome that includes
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`administering the aforementioned emulsion to the human’s eye.
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`A.
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`It was counterintuitive to combine 0.05% cyclosporin with a
`vehicle containing 1.25% castor oil
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`The claims reflect the inventors’ discovery that emulsions containing 0.05%
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`cyclosporin A in a vehicle containing 1.25% castor oil, polysorbate 80, and co-
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`polymers of acrylic acid were surprisingly effective, measured by standard
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`ophthalmic criteria, for treating dry eye disease relative to emulsions containing
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`twice as much cyclosporin or half as much castor oil described in the prior art Ding
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`‘979 patent. These results were surprising for a number of reasons.
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`Castor oil is cytotoxic and an irritant
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`1.
`Prior to the filing date of the ‘162 patent, castor oil was known to be
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`cytotoxic and an irritant. For example, one group of researchers wrote (EX. 2003
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`(Said et al.), p. 1):
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`Castor oil, which mainly contains ricinoleic acid (90% of total
`fatty acid content), is one of the lipophilic vehicles used in
`cyclosporine eye drops. However, it presents both a low-stability and
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`an epithelial and conjunctival toxicity as well as systemic adverse
`effects such as purgative effects, hypersensitivity, nephrotoxicity, and
`neurotoxicity. Since castor oil is presumed to be responsible for
`cytoxic effects in the eye, its replacement by another lipophilic vector
`could result in better tolerance of the drops.
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`These researchers then investigated 4 other vegetable oils as replacements for
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`castor oil. Id. Similarly, a different group noted that there was “significant corneal
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`edema” associated with castor oil when used as a vehicle for cyclosporin, causing
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`the group to discard it in favor of other lipophilic carriers. EX. 2004 (Alba et al.),
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`p. 7. And Ding ‘979 states that “conventional teaching in the art is away from a
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`formulation which utilizes a higher fatty acid glyceride, such as castor oil, and
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`cyclosporine.” EX. 1003 ((Ding ‘979), 3:46-48.
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`Because of the cytotoxic and other undesirable properties of castor oil, a
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`person of ordinary skill looking for a lipophilic vehicle in which to dissolve the
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`highly lipophilic cyclosporin either would have chosen a carrier other than castor
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`oil or, if he chose castor oil, would have used the minimum amount necessary to
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`dissolve cyclosporin. Given that the Ding ‘979 patent described emulsions
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`containing 0.05% cyclosporin in a vehicle with 0.625% castor oil and polysorbate
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`80, a person of ordinary skill would have recognized that a concentration of
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`0.625% was sufficient to dissolve cyclosporin and would not have selected a
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`higher amount—certainly not 1.25% castor oil, which was twice as high.
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`Apotex’s Dr. Xia agrees that castor oil was known to cause eye irritation and
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`would direct a person of skill to use a lower amount rather than a higher amount of
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`castor oil in the emulsion. Petition, pp. 32-33; EX. 1005 (Xia Decl’n), ¶ 117.
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`According to Dr. Xia, this explains what would have “directed a POSA towards the
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`1.25% emulsion over higher castor oils concentrations.” Id. But that simply begs
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`the question: why wouldn’t it instead direct a person of skill toward the 0.625%
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`emulsion over higher castor oil concentrations? Apotex and Dr. Xia never answer
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`that question. The inventors’ decision to combine 0.05% cyclosporin with a
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`vehicle containing 1.25% castor oil and polysorbate 80 was counterintuitive and
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`not obvious.
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`2.
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`Increasing the amount of castor oil in the emulsion would be
`expected to reduce the thermodynamic activity of the emulsion
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`
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`A person of skill would know the basic thermodynamic principles governing
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`diffusion and that increasing the amount of castor oil in the emulsion would reduce
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`the diffusion of the cyclosporin out of the castor oil and into the tissues of the eye.
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`The Ding ‘979 patent discussed using enough oil to maintain a stable composition
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`that did not cause the cyclosporin to precipitate, but not too much to reduce the
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`necessary thermodynamic activity necessary for the cyclosporin to diffuse out of
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`the emulsion and into the eye. EX. 1003 (Ding ‘979), 2:46-57; 3:7-38; 5:18-25.
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`The Ding ‘979 patent discloses emulsions containing 0.05% cyclosporin/0.625%
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`castor oil and 0.10% cyclosporin/1.25% castor oil. Id., Ex. 1 at 4:32-43. The Ding
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`‘979 patent explains that when formulated in the way instructed, “the drug has
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`reasonably high thermodynamic activity.” Id., 3:25-27.
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`Apotex’s Dr. Xia agrees that basic thermodynamic principles govern the
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`diffusion of cyclosporin out of the emulsion. Petition, pp. 32-33; EX. 1005 (Xia
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`Decl’n, ¶ 117. Indeed, Dr. Xia acknowledges that increasing the amount of castor
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`oil would reduce the amount of drug diffusing out of the emulsion and lead to
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`poorer drug bioavailability. Id. Dr. Xia then argues that because of this
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`thermodynamic issue, “a POSA would have reason to select 1.25% castor oil
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`(instead of a higher amount) to stay within the preferred ratio of CsA to castor oil,
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`while improving residence time on the eye.” Id. But again, Dr. Xia and Apotex do
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`not explain why it would not cause a person of skill to use an emulsion with
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`0.625% castor oil, which would have better thermodynamic properties and which
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`the prior art Ding ‘979 patent discloses as having “reasonably high thermodynamic
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`activity.” The inventors’ decision to combine 0.05% cyclosporin with a vehicle
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`containing 1.25% castor oil and polysorbate 80 simply was counterintuitive and
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`not obvious.
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`3.
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`PK data predicted 0.05% cyclosporin/1.25% castor oil would be
`less effective than 0.05% cyclosporin/0.625% castor oil and 0.1%
`cyclosporin/1.25% castor oil
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`Allergan performed PK studies on animal eyes that compared the PK
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`properties of 3 different ophthalmic emulsions:
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`(1) 0.05% cyclosporin/1.25% castor oil/1.00% polysorbate 80,
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`(2) 0.05% cyclosporin/0.625% castor oil/1.00% polysorbate 80, and
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`(3) 0.1% cyclosporin/1.25% castor oil/1.00% polysorbate 80.
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`The latter two emulsions are described in the Ding ‘979 patent. Dr. Mayssa
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`Attar, in her declaration submitted during prosecution of the ‘162 patent, described
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`these experiments. EX. 2008, pp. 62-64 (Decl’n of Dr. Mayssa Attar, ¶¶ 6-8). As
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`Dr. Attar explained, in order to obtain cyclosporin’s anti-inflammatory and anti-
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`apoptotic therapeutic effects, it must be delivered to ocular tissues such as the
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`cornea, conjunctiva, and lacrimal gland. Id. (¶ 6)). The more cyclosporin that
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`reaches these tissues, the more therapeutically effective the drug will be in treating
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`dry eye. Id.
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`PK studies involving animal eyes are used to evaluate the amount of drug
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`absorbed in ocular tissues. Allergan performed PK studies comparing the extent to
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`which the cyclosporin in the 3 above-described emulsions was absorbed in two
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`ocular tissues: the cornea and the conjunctiva. Id. (¶ 7). As shown in the graph,
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`reproduced below, and explained by Dr. Attar, the results show that in both the
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`cornea and conjunctiva, the amount of cyclosporin delivered to the ocular tissue
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`was greater in emulsions containing 0.05% cyclosporin/0.625% castor oil and
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`0.1% cyclosporin/1.25% castor oil than in the claimed emulsion containing 0.05%
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`cyclosporin/1.25% castor oil. Id.
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`Based upon these results, according to Dr. Attar, a person of ordinary skill would
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`have expected that both the 0.05% cyclosporin/0.625% castor oil and 0.1%
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`cyclosporin/1.25% castor oil emulsions would have been more therapeutically
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`effective for treating dry eye disease than the claimed emulsion. Id., p. 64 (¶ 8). In
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`other words, one would expect that increasing the amount of castor oil relative to
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`the amount of cyclosporin would decrease bioavailability and thus therapeutic
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`effectiveness. Apotex’s expert, Dr. Ta, agreed with Dr. Attar’s characterization of
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`the PK data (EX. 1007, ¶ 55):
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`[I]t would not be surprising that the formulation containing the
`higher amount of castor oil (1.25%) and the lowest amount of CsA
`(0.05%) showed lower bioavailability in [Exhibit B] because the
`presence of a higher percentage of castor oil in the emulsion would
`affect emulsion particle size, stability and release rate of the lipophilic
`CsA into the tissue …. Finally, it would not be surprising that the
`emulsion containing 0.1% CsA and 1.25% had higher bioavailability
`when compared to the emulsion containing 0.05% CsA and 1.25%
`castor oil (even though they both contained 1.25% castor oil) because
`the 0.1% CsA emulsion would have contained twice as much CsA
`compared to the 0.05% CsA emulsion …. Thus, the data presented in
`[Exhibit B] are not surprising.
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`Dr. Ta, Dr. Xia, and Dr. Attar, therefore, all agree that utilizing a higher amount of
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`castor oil in the emulsion should lead to less diffusion into the ocular tissues and
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`lower bioavailability.
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`But the actual results, based upon standard ophthalmic measures of efficacy,
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`tell a different story. During prosecution, Allergan presented the results of
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`experiments comparing the claimed emulsion to the two emulsions disclosed in the
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`Ding ‘979 patent, measured according to two key objective testing parameters for
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`dry eye: Schirmer Tear Testing and decrease in Corneal Staining. Exhibit E,
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`attached to the Declaration of Dr. Rhett Schiffman, shows the results of two studies
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`comparing the performance of a 0.05% cyclosporin/0.625% castor oil emulsion to
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`that of a 0.05% cyclosporin/1.25% castor oil emulsion. EX. 2008, pp. 40-41 and
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`58-59 (Decl’n of Dr. Rhett Schiffman, ¶¶ 17-19 and Exhibit E). In both studies,
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`the 0.05% cyclosporin/1.25% castor oil emulsion performed significantly better
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`than the 0.05% cyclosporin/0.625% castor oil emulsion—contrary to what the PK
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`experiments predicted. See id.
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`Allergan also presented results comparing the performance of a 0.1%
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`cyclosporin/1.25% castor oil emulsion with the claimed 0.05% cyclosporin/1.25%
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`castor oil emulsion with respect to 4 parameters: Corneal Staining, Schirmer Tear
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`Testing, blurred vision, and decrease in the number of artificial tears (palliative
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`treatment) used by patients. The results are shown in Exhibit D attached to the
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`Declaration of Dr. Rhett Schiffman. EX. 2008, pp. 38, 40, and 55-57 (Decl’n of
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`Dr. Rhett Schiffman, ¶¶ 8 and 14-16 and Exhibit D). The claimed 0.05%
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`cyclosporin/1.25% castor oil emulsion performed better than the 0.1%
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`cyclosporin/1.25% castor oil emulsion with respect to Schirmer Tear Testing,
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`blurred vision, and use of artificial tears, and was comparable with respect to
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`Corneal Staining. Id. Again, these results were contrary to what the PK
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`experiments predicted. See id.
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` The test results depicted in Exhibit D correspond to Phase 3 clinical
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`testing Allergan conducted, which is also described in the Sall paper (EX. 1004).
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`The important distinction between the two is that Sall does not describe the
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`composition of the vehicles, instead noting that their formulations were
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`proprietary. Sall merely recites emulsions containing either 0.05% cyclosporin or
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`0.1% cyclosporin. Thus, a person of ordinary skill reading the Sall paper would
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`not have known the materials in the vehicles and certainly not the castor oil content
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`of the vehicles tested. Based upon the Ding ‘979 patent, which described
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`emulsions containing 0.05% cyclosporin/0.625% castor oil/1.00 polysorbate 80
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`and 0.1% cyclosporin/1.25% castor oil/1.00% polysorbate 80, it would have been
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`entirely logical for a person of ordinary skill to conclude that Sall was testing those
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`two emulsions, rather than the claimed emulsion.
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`B. During prosecution the Examiner agreed that the performance of
`the claimed emulsion relative to the Ding ‘979 patent was
`unexpected
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`The Examiner repeatedly rejected the ‘162 patent claims as obvious over the
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`Ding ‘979 patent during prosecution. The Examiner agreed to withdraw the
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`rejection and allow the claims on the basis of Allergan’s evidence of unexpected
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`results. In her reasons for allowance, the Examiner stated (EX. 2008, p. 15)
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`(emphasis added):
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