`571-272-7822
`
` Date: July 21, 2021
`
`
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`ETON PHARMACEUTICALS, INC.,
`Petitioner,
`v.
`
`EXELA PHARMA SCIENCES, LLC,
`Patent Owner.
`____________
`
`PGR2020-00068
`Patent 10,583,155 B1
`____________
`
`
`
`Before ULRIKE W. JENKS, SUSAN L. C. MITCHELL, and
`CHRISTOPHER G. PAULRAJ, Administrative Patent Judges.
`
`JENKS, Administrative Patent Judge.
`
`
`
`
`DECISION
`Denying Petitioner’s Request on Rehearing of Decision Denying Institution
`of Post Grant Review
`37 C.F.R. § 42.71(d)
`
`
`
`
`
`
`
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`PGR2020-00068
`Patent 10,583,155 B1
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`I. INTRODUCTION
`Eton Pharmaceuticals Inc. (“Petitioner”) requests rehearing of our
`Institution Decision (“Decision”) denying post-grant review of claims 1–30
`of U.S. Patent No. 10,583,155 B1 (Ex. 1001, “the ’155 patent”) entered on
`December 15, 2020 (Paper 11, “Dec.”). Paper 12 (“Req. Reh’g”).
`We denied institution based on our determination that Petitioner’s
`contentions relying on reasonable expectation of success based on
`overlapping ranges was not sufficiently supported by the evidence in the
`record. Dec. 14–21.
`In its Request for Rehearing, Petitioner contends that the Board in the
`Decision misapprehends Petitioner’s assertions that do not rely on
`overlapping ranges to establish unpatentability, and that the Board abused its
`discretion in finding that the Sandoz Label does not overlap with the claimed
`range. See generally Req. Reh’g.
`Having reconsidered Petitioner’s arguments in view of the Request for
`Rehearing we modify the Decision to incorporate and address Petitioner’s
`contentions with respect to their reasonable expectation of success
`assertions. For the reasons discussed below, the modification of our
`Decision does not alter the outcome. As a result, we deny Petitioner’s
`Request for Rehearing.
`STANDARD OF REVIEW
`II.
`A party requesting rehearing has the burden to show a decision should
`be modified by specifically identifying all matters the party believes were
`misapprehended or overlooked, and the place where each matter was
`addressed previously in a motion, opposition, or a reply. 37 C.F.R.
`§ 42.71(d). When rehearing a decision on institution, we review the decision
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`for an abuse of discretion. 37 C.F.R. § 42.71(c). An abuse of discretion may
`arise if a decision is based on an erroneous interpretation of law, if a factual
`finding is not supported by substantial evidence, or if the decision represents
`an unreasonable judgment in weighing relevant factors. Star Fruits S.N.C. v.
`United States, 393 F.3d 1277, 1281 (Fed. Cir. 2005); Arnold P’ship v.
`Dudas, 362 F.3d 1338, 1340 (Fed. Cir. 2004); In re Gartside, 203 F.3d
`1305, 1315–16 (Fed. Cir. 2000).
`III. ANALYSIS
`In its Request for Rehearing, Petitioner contends that the Board in the
`Decision misapprehends Petitioner’s reasonable expectation of success
`assertions, and abused its discretion in finding that the Sandoz Label does
`not overlap with the claimed range. See generally Req. Reh’g.
`1.) Reasonable Expectation of Success
`Petitioner argues that in the Petition it presented a separate reasonable
`expectation of success argument that is based on routine optimization, which
`does “not depend exclusively on or require overlapping ranges.” Req. Reh’g
`5; see e.g. Pet. 50 (“[T]he claimed range is the expected result of optimizing
`the Sandoz product in response to regulatory and market pressures to
`substantially reduce and eliminate aluminum from parenteral drug
`products.”).
`Petitioner further contends that the claimed aluminum levels were not
`new, and that a person of ordinary skill in the art would have had a
`reasonable expectation that the Sandoz Label product could be optimized to
`substantially eliminate aluminum. See Req. Reh’g 1–2. Specifically,
`Petitioner contends that the person of ordinary skill in the art would have
`known how to remove known aluminum sources. Id. at 3. Petitioner
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`contends that the Decision overlooks the dispositive impact of the
`knowledge one of ordinary skill in the art would have possessed about
`Schott coated glass vials in order to prevent aluminum leaching of the
`Sandoz product if packaged into such a vial. See id. at 4, n. 6.
`Even if we were to agree with Petitioner that the Petition included a
`separate “reasonable expectation of success argument” that does not rely on
`overlapping ranges, we again find that Patent Owner has the better position.
`In our Decision, we agreed with Petitioner that there was ample motivation
`for reducing aluminum levels in parenteral solutions. See Dec. 19. In the
`Decision, however, we explained that motivation alone is not sufficient for
`reaching a conclusion of obviousness because it does not, without more,
`provide a path for how to achieve the stated goal. Id.
`Petitioner contends that the Decision overlooks that a person of
`ordinary skill in the art would have eliminated “known sources of
`aluminum” (Req. Reh’g 3), for example by packaging the Sandoz Label
`product into “Schott coated glass vials” to arrive at the claimed invention
`(id. at 4 (citing Pet. 39–40, 42–44, 50–51).
`The issue is not whether an ordinary artisan would have recognized
`sources of aluminum contamination that could potentially be eliminated; the
`question is whether there would have been a reasonable expectation that
`removing an aluminum source would result in a stable product as defined by
`the ’155 patent. We agree with Patent Owner response that “the kinetics and
`equilibrium chemistry of the various L-cysteine and cystine species in any
`particular L-cysteine solution are complex and influenced by multiple
`interacting variables of that environment, including oxygen levels, pH, and
`the presence of trace metals.” Prelim. Resp. 17. Patent Owner further
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`explains “that ‘removing Aluminum may have the unintended consequence
`of increased [L-cystine] precipitation and product failure in the presence of
`even small amounts of oxygen in the container.’” Id. at 18 (alteration in
`original) (quoting Ex. 1001, 5: 12–15 (“[R]emoving Aluminum may have
`the unintended consequence of increased precipitation and product failure in
`the presence of even small amounts of oxygen in the container. This was
`unexpected.”)). In other words, the removal of aluminum has the unintended
`consequence of making the product more susceptible to oxygen, resulting in
`product precipitation, and thereby rendering the product unsuitable for
`parenteral administration. Id. at 18.
`Petitioner contends that it provided unrebutted expert testimony
`supporting its position. Req. Reh’g 4. “The Board has broad discretion to
`assign weight to be accorded expert testimony.” Consolidated Trial Practice
`Guide1 (“CTPG”) 35 (Nov. 2019). Here, we evaluate Petitioner’s expert
`testimony against the backdrop that it took more than a decade to develop a
`cysteine containing parenteral composition that met the FDA requirements.
`See Prelim. Resp. 3 (citing Ex. 1006; Ex. 1038; Ex. 2009; Ex. 2011; Ex.
`2012). Considering the great pressure given by the FDA recommendation to
`lower aluminum content in parenteral solutions to avoid aluminum toxicity
`and the length of time it took the industry to produce such a product, we find
`that on balance this suggests that the solution to the problem was not straight
`forward as urged by Petitioner. See Sur-reply 3–4; Prelim. Resp. 10, 17
`(citing Ex. 1002 at 378–379), 44 (citing Leo Pharm. Prods., Ltd. v. Rea, 726
`F.3d 1346, 1354 (Fed. Cir. 2013) (“If these discoveries and advances were
`
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`1 Available at https://www.uspto.gov/TrialPracticeGuideConsolidated.
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`routine and relatively easy, the record would undoubtedly have shown that
`some ordinary artisan would have achieved this invention within months of
`[the prior art patents]. Instead this invention does not appear for more than a
`decade.”)).
`We also agree with Patent Owner that Petitioner’s routine
`optimization argument is infected with hindsight assumptions and ignores
`the complexity of the environmental conditions that contribute to the
`aluminum levels in parenteral solutions. Prelim. Resp. 38–40, 54; Dec. 18.
`Here, the person of ordinary skill in the art was highly motivated to solve the
`“alleged ‘problem of aluminum’” and yet the problem had “gone unsolved
`for more than a decade” despite the supposedly “simple and straightforward
`solutions.” Id. at 39–40 (citing Leo Pharm. Prods., 726 F.3d at 1354), 57.
`Given this backdrop, we agree with Patent Owner’s assertion that Petitioner
`has not articulated why a person of ordinary skill in the art would have had a
`reasonable expectation of success in solving the decades-old aluminum
`problem. Id. at 9 (citation and quotation omitted).
`2.) Range
`We are also not persuaded by Petitioner’s contention that we abused
`our discretion in determining that the Sandoz Label does not disclose
`overlapping ranges. Petitioner contends that Dr. Rabinow’s testimony is
`unrebutted. Req. Reh’g 7. Therefore, we should accept the testimony that a
`person of ordinary skill in the art would have interpreted the Sandoz Label
`as disclosing an aluminum concertation “falling somewhere within the range
`of 0 ppb to 5,000 ppb” (i.e., 5,000 ppb aluminum or less) and that the
`claim 1 range of from about 1-250 ppb aluminum is within the lower end of
`the “not more than 5,000 ppb range.” Id. The Board has broad discretion
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`how much weight to give expert testimony. CTPG 25. “Opinions expressed
`without disclosing the underlying facts or data may be given little or no
`weight.” Rohm & Haas Co. v. Brotech Corp., 127 F.3d 1089, 1092 (Fed.
`Cir. 1997) (nothing in the Federal Rules of Evidence or Federal Circuit
`jurisprudence requires the fact finder to credit unsupported assertions of an
`expert witness)” CTPG 40.
`In this case, Petitioner has not directed us to corroborating evidence to
`suggest that zero is a reasonable lower limit based on the disclosure in the
`Sandoz Label. To the contrary, Petitioner directs to evidence in the record
`(see Pet. 33 (citing Ex. 1022 ¶ 15 (citing Exhibit B and C))) that supports the
`warning in the Sandoz Label’s that the product contains aluminum,
`establishing that the lower limit is not reasonably zero. See Dec. 8 (citing
`Ex. 1005 at 2 (“This product contains aluminum that may be toxic.”).
`Accordingly, we are not persuaded by Petitioner’s contention that we abused
`our discretion to arrive at the conclusion that the disclosure of the Sandoz
`Label does not overlap with or encompass the 1-250 ppb aluminum range
`recited in claim 1 of the ’155 patent.
`In the Decision, we determined that the Sandoz Label describes a
`product. Specifically, the label states that the contents contains a solution
`having “50 mg of L-cysteine hydrochloride monohydrate, Water for
`Injection, USP q.w.; Air replaced with nitrogen. pH 1.0-2.5.” Dec. 10 (citing
`Ex. 1005, 1). In the Decision, we identified that the Sandoz Label also
`recognizes that the product contains aluminum, evidencing that zero is not a
`reasonable endpoint as urged by Petitioner. Dec. 11 (citing Ex. 1005 at 2
`(“This product contains aluminum that may be toxic.”). The Sandoz Label
`then lists that “the product contains no more than 5000 mcg/L [(5000 ppb)]
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`of aluminum.” Dec. 11. In the Decision, we credited Dr. Kuhn’s testimony,
`which is supported by the record, and determined that the evidence supports
`the position that the 5000 mcg/L aluminum concentration at product
`expiration is the number used for “calculating a patient’s aluminum
`exposure.” Dec. 18 (citing Ex. 2001 ¶ 20–24), 19 (“the recitation of
`‘contains no more than 5000 mcg/ml (i.e. 5000 ppm) aluminum’ is more
`reasonably interpreted to be the upper end of the aluminum concentration
`that is expected in the product rather than a teaching of any lower limit for
`the aluminum content that overlaps with the claimed range.”). Based on
`these disclosures in the Sandoz Label we concluded that the evidence in the
`record does not support Petitioner’s position, that “the Sandoz Label teaches
`range of 0 to 5,000 mcg/L” an interpretation relied on in Petitioner’s
`articulated grounds of unpatentability. See Dec. 15.
`IV. CONCLUSION
`We have reconsidered our decision of December 15, 2020, in light of
`
`Petitioner’s comments in the Request for Rehearing, and we modify our
`Decision in response to Petitioner’s argument by incorporating our analysis
`herein with respect to the “reasonable expectation of success” argument (see
`above III.1) that Petitioner asserts does not rely on overlapping ranges. For
`the foregoing reasons, Petitioner has not demonstrated that we abused our
`discretion in exercising our discretion to deny institution.
`V. ORDER
`In consideration of the foregoing, it is hereby ordered that the
`
`Petitioner’s Rehearing Request is denied.
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`PGR2020-00068
`Patent 10,583,155 B1
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`PETITIONER:
`Ralph J. Gabric
`Eugene Goryunov
`Jeff Wolfson
`Judy K. He
`HAYNES AND BOONE LLP
`ralph.gabric.ipr@haynesboone.com
`eugene.goryunov.ipr@haynesboone.com
`jeff.wolfson.ipr@haynesboone.com
`judy.he.ipr@haynesboone.com
`
`PATENT OWNER:
`Dorothy P. Whelan
`Alana Mannige
`FISH & RICHARDSON P.C.
`whelan@fr.com
`mannige@fr.com
`
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