Orexo Ab v. Actavis Elizabeth LLC , 903 F.3d 1265 ( 2018 )


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  •   United States Court of Appeals
    for the Federal Circuit
    ______________________
    OREXO AB, OREXO US INC.,
    Plaintiffs-Appellants
    v.
    ACTAVIS ELIZABETH LLC,
    Defendant-Appellee
    ______________________
    2017-1333
    ______________________
    Appeal from the United States District Court for the
    District of Delaware in No. 1:14-cv-00829-SLR-SRF,
    Judge Sue L. Robinson.
    ______________________
    Decided: September 10, 2018
    ______________________
    ERROL TAYLOR, Milbank, Tweed, Hadley & McCloy,
    LLP, New York, NY, argued for plaintiffs-appellants.
    Also represented by ANNA BROOK, JORDAN P. MARKHAM,
    FREDRICK ZULLOW.
    GEORGE C. LOMBARDI, Winston & Strawn LLP, Chica-
    go, IL, argued for defendant-appellee. Also represented
    by TYLER JOHANNES, MICHAEL KEENAN NUTTER, IVAN
    MICHAEL POULLAOS; GEOFFREY P. EATON, Washington,
    DC.
    ______________________
    2                        OREXO AB   v. ACTAVIS ELIZABETH LLC
    Before NEWMAN, HUGHES, and STOLL, Circuit Judges.
    NEWMAN, Circuit Judge.
    Orexo AB and Orexo US Inc. (collectively “Orexo”) ap-
    peal the decision of the United States District Court for
    the District of Delaware, holding claims 1, 3–6, and 8–10
    of 
    U.S. Patent No. 8,940,330
     (“the ’330 Patent”) invalid on
    the ground of obviousness. 1 The ’330 Patent, entitled
    “Abuse-Resistant Pharmaceutical Composition for the
    Treatment of Opioid Dependence,” claims a product
    having the brand name Zubsolv®, approved by the FDA
    for treatment of opioid dependence.
    Actavis Elizabeth LLC (“Actavis”) filed an Abbreviat-
    ed New Drug Application (“ANDA”) for a generic counter-
    part of Zubsolv, accompanied by a Paragraph IV
    certification, leading to this Hatch-Waxman litigation in
    accordance with 
    21 U.S.C. § 355
    (j) and 
    35 U.S.C. § 271
    (e)(2)(A). Two Orexo patents were challenged by
    Actavis, but 
    U.S. Patent No. 8,454,996
     (“the ’996 Patent”),
    entitled “Pharmaceutical Composition for the Treatment
    of Acute Disorders,” which was held valid in the district
    court, is not involved in this appeal.
    We reverse the judgment of invalidity of the ’330 Pa-
    tent, for we conclude that obviousness was not proved by
    clear and convincing evidence.
    BACKGROUND
    A
    The ’330 Patent
    The ’330 Patent specification explains that opioid-
    based pharmaceutical products intended for the relief of
    pain have become a source of addiction, dependency, and
    1  Orexo AB v. Actavis Elizabeth LLC, 
    217 F. Supp. 3d 756
     (D. Del. 2016) (“Dist. Ct. Op.”).
    OREXO AB   v. ACTAVIS ELIZABETH LLC                       3
    abuse. Treatment for opioid addiction includes a protocol
    called “substitution therapy,” where partial opioid ago-
    nists 2 that have higher binding affinities at opioid recep-
    tors but produce lowered dependency than full agonists
    like heroin, can lead to cessation of addiction by relieving
    the opioid craving. The prior art shows use for this pur-
    pose of the partial agonist buprenorphine, administered
    in sublingual tablets and in oral films.
    The ’330 Patent explains that while buprenorphine
    has less narcotic effect than a full opioid, addicts were
    known to dissolve the buprenorphine from the substitu-
    tion therapy tablet, and inject the dissolved buprenor-
    phine intravenously to achieve an enhanced opioid effect.
    To counteract this abuse, it was known to combine bu-
    prenorphine with the opioid antagonist 3 naloxone in
    substitution therapy.
    It was known that formulations containing buprenor-
    phine to naloxone at a ratio of 4:1 provide the therapeuti-
    cally optimal balance for sublingual treatment. Naloxone
    has poor transmucosal bioavailability so that if the mix-
    2      An agonist is a chemical compound that binds to a
    receptor and activates the receptor to produce a biological
    response. Partial opioid agonists have opioid agonist
    effects that “are less than the maximal effects of other,
    ‘full’ opioid agonists, such as morphine, and are limited by
    a ‘ceiling’ effect. The drug thus produces a lower degree of
    physical dependence than other opioid agonists, such as
    heroin, morphine, or methadone, and is therefore particu-
    larly useful in substitution therapy.” ’330 Patent, col. 9,
    ll. 19–29.
    3    “Opioid antagonists are used to reverse the phar-
    macological effects of opioids. Selective opioid antago-
    nists, such as naloxone, may therefore be used to treat
    drug overdose or to diagnose suspected opioid addiction.”
    ’330 Patent, col. 1, l. 65–col. 2, l. 1.
    4                          OREXO AB   v. ACTAVIS ELIZABETH LLC
    ture is taken in tablet form as directed, the buprenor-
    phine will act as intended to treat opioid dependence with
    little interference from the naloxone. However, if the
    tablet is dissolved and injected, the naloxone will antago-
    nize the effects of the buprenorphine, resulting in with-
    drawal symptoms and thus deterring abuse of the
    formulation.     The 4:1 ratio provides for appropriate
    pharmacological amounts of naloxone to deter abuse when
    injected, but does not interfere with buprenorphine when
    taken in tablet form. ’330 Patent, col. 2, ll. 13–22; 
    id.,
     col.
    9, ll. 37–50. However, naloxone’s “functional blockade of
    buprenorphine’s action is also only partial and is short-
    lived in its nature,” 
    id.,
     col. 2, ll. 23–25, and there was a
    continuing need for improvement in substitution therapy
    formulations.
    The ’330 Patent is for a sublingual tablet formulation
    that is less subject to abuse. The formulation enhances
    the agonist effectiveness of buprenorphine, permitting a
    reduced amount of buprenorphine in the tablet and thus
    reducing the amount available on dissolving and injecting
    the product. In this formulation, microparticles of bu-
    prenorphine are adhered to the surface of carrier particles
    of citric acid, and the formulation also contains naloxone
    in the 4:1 ratio. The ’330 Patent explains that the bu-
    prenorphine in the microparticles acts with little interfer-
    ence from the naloxone, but if the tablet is dissolved in
    water for injection into the bloodstream, the naloxone will
    also be dissolved and will antagonize buprenorphine’s
    effects.
    All parties agree that the product in the ’330 Patent
    provides improved treatment of opioid dependence, as
    compared with the prior art. The ’330 Patent specifica-
    tion includes data from clinical trials comparing the
    related sublingual product Suboxone®. Patent Example 2
    shows a 66% improvement in bioavailability of buprenor-
    phine, and Patent Examples 7 and 8 show bioequivalent
    OREXO AB   v. ACTAVIS ELIZABETH LLC                        5
    results for a sublingual tablet containing 29% less bu-
    prenorphine than in Suboxone tablets.
    Actavis does not dispute the improvement, or its value
    in treatment of addiction. Rather, Actavis argues that
    this formulation is obvious based on a combination of
    references, and that improved function and use are irrele-
    vant if the product is obvious. This theory is flawed, for
    an unobvious improvement in properties or use is highly
    relevant to patentability of a new product.
    Claims 1 and 6 were deemed representative:
    1. A tablet composition suitable for sublingual
    administration comprising:
    microparticles of a pharmacologically-effective
    amount of buprenorphine, or a pharmaceutically-
    acceptable salt thereof, presented upon the sur-
    face of carrier particles,
    wherein microparticles of buprenorphine or a
    pharmaceutically acceptable salt thereof are in
    contact with particles comprising citric acid,
    wherein the buprenorphine or pharmaceuti-
    cally acceptable salt thereof and the citric acid are
    not in the same particle;
    a pharmacologically-effective amount of na-
    loxone, or a pharmaceutically-acceptable salt
    thereof;
    and a disintegrant selected from the group
    consisting of croscarmellose sodium, sodium
    starch glycolate, crosslinked polyvinylpyrrolidone
    and mixtures thereof.
    6. The composition as claimed in claim 1, wherein
    the particles of citric acid are presented and act as
    carrier particles.
    6                        OREXO AB   v. ACTAVIS ELIZABETH LLC
    The district court found that all the ingredients in the
    claims were generally known, and held that although the
    specific formulation was not shown or suggested in any
    reference, the new combination would have been obvious
    to a person of ordinary skill. However, the prior art does
    not show or suggest the claimed combination, and does
    not show or suggest that this combination would achieve
    enhanced therapeutic effect while being less subject to
    abuse.
    B
    The Prior Art
    1. Suboxone® and Subutex®
    The buprenorphine and naloxone combination in the
    4:1 ratio has been used for substitution therapy at least
    since 2002. The prior art Suboxone sublingual tablets are
    a homogeneous combination made by mixing the ingredi-
    ents of buprenorphine, naloxone, citric acid, sodium
    citrate, and sublingual excipients. Dist. Ct. Op. at 769
    n.17 (citing Physicians’ Desk Reference, 58th ed. 2004).
    Subutex® is the same formulation as Suboxone, but
    without the naloxone. WO2008/152347 (“Cairns”), cited
    by the examiner during prosecution, describes the tablet
    formulation as a wet granulation process where bupren-
    orphine, citric acid, and sodium citrate are dissolved
    together and then mixed with excipients. See Orexo Br.
    at 14 & n.2 (“Cairns provides the manufacturing process
    for Subutex® tablets, a product with essentially the same
    formulation as Suboxone® tablets, but without nalox-
    one.”).
    Orexo attributes the improvements achieved by the
    Zubsolv product to the microparticles of buprenorphine
    adhered to the surface of citric acid carrier particles.
    Orexo states that the 66% higher bioavailability is not
    suggested or reasonably predictable from the prior art.
    We have been directed to no reference to show or suggest
    OREXO AB   v. ACTAVIS ELIZABETH LLC                        7
    otherwise. Orexo stresses the Examiner’s statement in
    allowing the ’330 Patent, that the improvement is due to
    the ingredients and the structure:
    [T]he mere presence of citric acid in the sublin-
    gual tablets formulated according to the prior art
    (e.g. Cairns) is insufficient to achieve the superior
    pharmacokinetic profile exhibited by the instant
    invention. Applicant has persuasively demon-
    strated that the instant tablet exhibits unexpect-
    edly     superior      sublingual     buprenorphine
    bioavailability due to the ingredients as well as
    the structural characteristics recited in the in-
    stant claims.
    Notice of Allowability at 5 (emphasis original), Applica-
    tion No. 14/127,470 (issued as the ’330 Patent) (Nov. 4,
    2014); see also Orexo Br. at 29 (quoting Notice of Allowa-
    bility at 5).
    2. Suboxone® Film
    
    U.S. Patent No. 8,475,832
     (“the ’832 Patent”) de-
    scribes an orally dissolvable film that cannot be easily
    removed once placed inside the mouth. The film contains
    the buprenorphine/naloxone combination in the 4:1 ratio,
    and is described as bioequivalent to Suboxone sublingual
    tablets. The ’832 Patent teaches that optimum bioavaila-
    bility of buprenorphine and naloxone from the film is
    achieved at pH 3–3.5, with citric acid included in the film
    to lower the pH. The district court relied on this presence
    of citric acid to render obvious the citric acid carrier
    particles in the Zubsolv formulation.
    However, the ’832 Patent does not reduce the amount
    of buprenorphine needed to provide an effective substitu-
    tion therapy dose. And the use of film in substitution
    therapy presents recognized problems, as stated in the
    ’330 Patent, for the film does not dissolve quickly and a
    maximum of only two films may be administered simul-
    8                        OREXO AB   v. ACTAVIS ELIZABETH LLC
    taneously, producing inadequate dosage as well as prob-
    lems of compliance and administration. ’330 Patent, col.
    2, ll. 43–50.
    3. The Orexo Application
    Orexo’s U.S. Patent Application No. 2010/0129443
    (“the ’443 Application”), titled “Non-Abusable Pharmaceu-
    tical Composition Comprising Opioids,” was filed on
    December 3, 2007, published on May 27, 2010, and issued
    as 
    U.S. Patent No. 8,470,361
     on June 25, 2013. It is prior
    art as of its filing date.
    The ’443 Application describes sublingual tablets
    where smaller particles of opioid agonists are carried on
    larger particles that include an opioid antagonist. The
    ’443 Application lists many opioid agonists including
    buprenorphine, and many antagonists including naloxone.
    However, citric acid is not mentioned or suggested as the
    carrier particle.
    4.  European Patent Application No. EP
    0324725
    European Patent Application No. EP 0324725 (“the
    EP ’725 Application”) lists a large number of water-
    soluble carrier particles, to which smaller particles of a
    pharmaceutically active substance may be adhered. The
    EP ’725 Application does not mention sublingual tablets,
    does not mention opioids as the active substance, and
    does not mention citric acid as a carrier.
    C
    The District Court Decision
    The district court held the asserted ’330 Patent claims
    invalid, ruling that a skilled artisan would obviously have
    selected these components from the prior art and reformu-
    lated them as in the ’330 Patent. The district court stated
    that the ’443 Application taught that “a person of ordi-
    nary skill in the art would have been motivated to refor-
    OREXO AB   v. ACTAVIS ELIZABETH LLC                         9
    mulate Suboxone tablets as an interactive mixture to
    improve bioavailability,” Dist. Ct. Op. at 773; that the
    ’832 Patent for an oral film “expressly taught a person of
    ordinary skill that the addition of citric acid facilitated an
    increased level of absorption of buprenorphine despite a
    lower pH,” 
    id.
     at 772–73; and that the EP ’725 Application
    “described how to make such a mixture using dry mixing,”
    
    id. at 773
    .
    In response to Orexo’s argument that no reference
    showed the new formulation in the ’330 Patent, stressing
    the unexpectedly enhanced bioavailability and its bene-
    fits, the district court reasoned that a skilled artisan
    “would not have excluded citric acid” as a carrier and
    “would have known how to form an interactive mixture
    using citric acid.” 
    Id.
     The district court found that the
    ’832 Patent taught “the use of citric acid with an interac-
    tive mixture would also improve [buprenorphine] bioa-
    vailability,” 
    id.,
     and concluded that it would have been
    obvious to use citric acid as carrier particles.
    Orexo argued that a person of ordinary skill would
    have been dissuaded from using citric acid in this interac-
    tive mixture because Examples 6–8 of the ’832 Patent
    taught that as the pH is lowered through use of citric
    acid, the buprenorphine bioavailability increase is accom-
    panied by a compromised naloxone availability such that
    the 4:1 ratio is lost. The district court described this
    argument as irrelevant because the 4:1 ratio is an “un-
    claimed feature” of the ’330 Patent, the court stating “any
    problems with maintaining the ratio forecast by the ’832
    patent goes to the reasonable expectation of success
    requirement, not to motivation to combine; i.e., this
    argument is irrelevant in this context.” 
    Id.
     at 773 n.23.
    Orexo stresses that no reference teaches or suggests
    using citric acid particles as a carrier for micronized
    buprenorphine, and that the benefits of this formulation
    were unexpected. Rejecting this argument, the district
    10                        OREXO AB   v. ACTAVIS ELIZABETH LLC
    court cited the testimony of Actavis’ expert that citric acid
    “fits the definition of a carrier particle” and “therefore it
    would act as a carrier particle, because it is in the Subox-
    one tablet.” Dist. Ct. Op. at 771 (quoting testimony of Dr.
    Dyar). However, no reference suggests citric acid carrier
    particles.
    The district court also discussed the objective indicia
    of unobviousness, responding to Orexo’s arguments of
    unexpectedly increased bioavailability, long-felt need for
    improved treatment of opioid dependence, copying by
    Actavis, and hindsight. The court stated that “the unex-
    pected result of increased bioavailability provides some
    support for nonobviousness,” Dist. Ct. Op. at 776, but
    found that interactive mixtures were generally known to
    improve bioavailability and that the increase here was a
    “‘difference in degree,’ not a difference in ‘kind.’” 
    Id. at 774
    . The district court stated that Orexo’s arguments of
    teaching away, long-felt need, and copying were “not
    persuasive evidence.” 
    Id.
     at 773 n.27, 776. The court
    concluded that “Actavis has met its burden to prove, by
    clear and convincing evidence, that claims 1, 3–6, and 8–
    10 are obvious.” 
    Id. at 776
    .
    DISCUSSION
    Standard of Review
    Following a bench trial, we review the district court’s
    factual findings for clear error. Conclusions of law receive
    de novo determination. See In re Cyclobenzaprine Hydro-
    chloride Extended-Release Capsule Patent Litig., 
    676 F.3d 1063
    , 1069 (Fed. Cir. 2012) (“While we afford deference to
    a district court’s factual findings, however, we retain
    plenary review to determine whether, as a legal matter,
    the evidence satisfies the clear-and-convincing standard
    of proof.”).
    Obviousness is a question of law, based on the facts of
    (1) the scope and content of the prior art, (2) the level of
    OREXO AB   v. ACTAVIS ELIZABETH LLC                       11
    ordinary skill in the field, (3) the differences between the
    claimed invention and the prior art, and (4) any objective
    indicia of nonobviousness. Graham v. John Deere Co., 
    383 U.S. 1
    , 17–18 (1966). To invalidate a patent on the
    ground of obviousness, the challenger has the burden of
    proving that the subject matter as a whole would have
    been obvious to a person of ordinary skill in the field of
    the invention. 
    35 U.S.C. § 103
    (a). A party seeking to
    invalidate a patent on obviousness grounds must demon-
    strate by clear and convincing evidence that a person of
    ordinary skill would have selected and combined and
    modified the subject matter of the references in the man-
    ner of the claimed invention, with a reasonable expecta-
    tion of success.     E.g., InTouch Techs., Inc. v. VGO
    Commc’ns, Inc., 
    751 F.3d 1327
    , 1347 (Fed. Cir. 2014).
    Judicial hindsight must be avoided. See KSR Int’l Co.
    v. Teleflex Inc., 
    550 U.S. 398
    , 421 (2007) (“A factfinder
    should be aware, of course, of the distortion caused by
    hindsight bias and must be cautious of arguments reliant
    upon ex post reasoning.”). It is inappropriate to use the
    template provided by the inventor, to render the inven-
    tor’s contribution obvious. See Interconnect Planning
    Corp. v. Feil, 
    774 F.2d 1132
    , 1138 (Fed. Cir. 1985) (“The
    invention must be viewed not with the blueprint drawn by
    the inventor, but in the state of the art that existed at the
    time. The invention must be evaluated not through the
    eyes of the inventor, who may have been of exceptional
    skill, but as by one of ‘ordinary skill’.”).
    Obviousness
    In holding the ’330 Patent’s claims invalid for obvi-
    ousness, the district court cited the ’832 Patent to show
    that “the use of citric acid with an interactive mixture
    would also improve bioavailability.” Dist. Ct. Op. at 773.
    The ’832 Patent is for a film that includes citric acid to
    lower the pH of the film. Example 7 of the ’832 Patent
    shows that a lowering of pH to 5.5 increases buprenor-
    12                         OREXO AB   v. ACTAVIS ELIZABETH LLC
    phine bioavailability, but also compromises the desired
    4:1 ratio of buprenorphine to naloxone. ’832 Patent, col.
    21, ll. 17–26. Example 8 of the ’832 Patent shows that a
    further decrease in pH to 3.5 using citric acid maintained
    the 4:1 ratio but did not increase buprenorphine bioavail-
    ability. 
    Id.,
     col. 23, ll. 1–11. The ’832 Patent is directed to
    replacing sublingual tablets with oral film, for possible
    advantage in administration. There is no suggestion of
    the different structure of the Zubsolv tablet and its ad-
    vantage in deterring abuse. The Zubsolv structure is
    achieved solely upon the hindsight knowledge of the
    structure and benefits described in the ’330 Patent.
    The district court cited the Orexo ’443 Application for
    its disclosure of particles of buprenorphine adhered to
    carrier particles. However, the ’443 Application does not
    mention citric acid in its extensive list of carriers, and
    does not suggest that citric acid carrier particles may
    provide benefits compared with the prior art. These
    benefits were not predicted or suggested in any reference.
    The district court cited the EP ’725 Application for its
    general description of interactive mixtures as pharmaceu-
    tical formulations. This reference does not mention
    opioids, does not mention sublingual tablets, does not
    mention citric acid in its extensive list of carrier particles,
    and does not suggest the formulation in the ’330 Patent or
    its unexpected benefits.
    The product herein is admittedly new. The district
    court acknowledged the undisputed testimony of Orexo’s
    co-founder, Mr. Thomas Lundqvist, and Orexo’s global
    chief medical officer, Dr. Michael Sumner. The district
    court wrote:
    Lundqvist testified that the first clinical results
    showed that Zubsolv had a 66% improvement in
    bioavailability. (D.I. 202 at 58:9–15; D.I. 211 at
    36) According to a bioequivalence study, Zubsolv
    increases the bioavailability of buprenorphine,
    OREXO AB   v. ACTAVIS ELIZABETH LLC                         13
    such that patients require a 29% lower dose using
    Zubsolv as compared to Suboxone. (JTX 153; D.I.
    202 at 63:11–17 [Testimony of Mr. Lundqvist];
    D.I. 205 at 770:22–771:3 [Testimony of Dr.
    Sumner]; D.I. 196 at 12) Orexo’s pharmaceutical
    development report stated that “[d]ue to the antic-
    ipated improved dissolution of buprenorphine the
    selected dose of 6 mg buprenorphine is expected to
    give approximately the same systemic buprenor-
    phine exposure in humans as a Suboxone® tablet
    with 8 mg buprenorphine.” (JTX 123 at 4; JTX
    128 at 32; D.I. 203 at 352:11–22)
    Dist. Ct. Op. at 760 (citations in original, bracketed
    information added).
    The district court nonetheless concluded that the Zub-
    solv formulation was obvious. The court cited Actavis’s
    expert Dr. Dyar as showing that “citric acid is pharma-
    ceutically acceptable, water soluble, and of the right size,
    so therefore it would act as a carrier particle, because it is
    in the Suboxone tablet.” Dist. Ct. Op. at 771 (quoting J.A.
    6685, June 8, 2016 Trial Tr. at 433:12–15, ECF No. 204
    (Testimony of Dr. Dyar)). Orexo points out that Dr. Dyar
    cited no reference, and describes this reasoning as “hind-
    sight bias,” for it recreates the prior art from the teaching
    in the ’330 Patent. Orexo points out that citric acid is
    nowhere used or listed or suggested as a carrier particle,
    and it is not so used in the Suboxone tablet.
    At the oral argument of this appeal, Actavis conceded
    that no reference teaches using citric acid as a carrier
    particle, or that citric acid should be used as a carrier
    particle:
    Actavis Counsel: Your Honor, I will confirm what
    counsel said before and what we’ve said in our
    briefs. There is no piece of prior art that was pre-
    sented that says citric acid is a carrier particle or
    should be used as a carrier particle.
    14                         OREXO AB   v. ACTAVIS ELIZABETH LLC
    Oral. Arg.      at 21:19–21:36, http://oralarguments.
    cafc.uscourts.gov/default.aspx?fl=2017-1333.mp3.
    Court: If both of those things are really well
    known, then one would think that if citric acid
    were routinely or it was obvious to use it as a car-
    rier particle, you could have found some reference
    that used it. . . . Your expert didn’t even testify
    that he was familiar with this industry and that
    citric acid was routinely used as a carrier particle
    in interactive mixtures. He just said it was the
    right size and it could be used.
    Actavis Counsel: Well. You’re right Your Honor in
    terms of your characterization of the record.
    There was not citric acid used as a carrier particle
    that was in the record.
    
    Id.
     at 26:12–26:50.
    Dr. Dyar did not testify that a skilled artisan would
    obviously select citric acid as a carrier for buprenorphine;
    he stated that if it were selected, the artisan would expect
    it to work. The district court’s finding that “a person of
    ordinary skill in the art would not have excluded citric
    acid,” Dist. Ct. Op. at 773, is not a teaching or suggestion
    to use citric acid. See In re Gordon, 
    733 F.2d 900
    , 902
    (Fed. Cir. 1984) (“The mere fact that the prior art could be
    so modified would not have made the modification obvious
    unless the prior art suggested the desirability of the
    modification.”). The record does not contain clear and
    convincing evidence of a teaching or suggestion to use
    citric acid particles as a carrier for this opioid product in
    substitution therapy, or that the actual beneficial results
    would be obtained.
    Orexo also argued that the specific formulation in the
    ’330 Patent preserves the 4:1 ratio of buprenorphine to
    naloxone during use of the product, unlike the prior art
    products. The district court stated that this benefit is
    OREXO AB   v. ACTAVIS ELIZABETH LLC                        15
    irrelevant because it “goes to the reasonable expectation
    of success requirement, not to motivation to combine.”
    Dist. Ct. Op. at 773 n.23. The district court found that
    “there is nothing in the prior art which would have dis-
    couraged a person of ordinary skill from following the
    path set out in the various references.” Id. at 773. How-
    ever, no reference or combination of references proposes
    the path of the ’330 Patent.
    The question is not whether the various references
    separately taught components of the ’330 Patent formula-
    tion, but whether the prior art suggested the selection and
    combination achieved by the ’330 inventors. Although the
    reference ’832 Patent showed that buprenorphine bioa-
    vailability in the film formulation is affected by pH, this is
    not a suggestion of the sublingual tablet interactive
    formulation in the ’330 Patent or a teaching of its benefit
    in deterring abuse.
    The references show that the field of opioid biophar-
    macology has received extensive scientific study. The ’330
    Patent provides a significant improvement. Despite the
    extensive study, this improvement over the then-available
    treatments for addiction is not proposed or suggested in
    the references. There is no suggestion that the specified
    elements should be selected and combined, and that the
    designated sublingual formulation would be less subject
    to abuse than prior formulations for substitution therapy.
    Although the need to reduce this abuse was known,
    recognizing a need does not render the solution obvious.
    Here, the objective indicia guide the analysis of obvi-
    ousness. See, e.g., Leo Pharm. Prods., Ltd. v. Rea, 
    726 F.3d 1346
    , 1357–58 (Fed. Cir. 2013) (“[T]his court has
    emphasized that consideration of the objective indicia is
    part of the whole obviousness analysis, not just an after-
    thought.”). The district court stated, “the unexpected
    result of increased bioavailability provides some support
    for nonobviousness,” although the court also stated that
    16                        OREXO AB   v. ACTAVIS ELIZABETH LLC
    Orexo’s long-felt need and copying arguments “are not
    persuasive evidence of such.” Dist. Ct. Op. at 776. The
    court reasoned that the prior art sought to improve bioa-
    vailability, that interactive mixtures were known to
    improve bioavailability, and therefore that the improved
    result of the ’330 Patent’s formulation was inadequate to
    serve as probative evidence of unexpected results. See 
    id. at 774
    .
    Orexo states that the district court erred, for the prior
    art does not teach or suggest the ’330 Patent’s formulation
    as a way to improve bioavailability. Actavis responds
    that the prior art is silent “about whether it would be
    expected or difficult ‘to increase buprenorphine absorption
    without simultaneously increasing naloxone absorption to
    unacceptable levels.’” Actavis Br. at 62. Orexo counters
    that silence is not a teaching or suggestion; and that the
    beneficial results could not be predicted, and were indeed
    unexpected. 4
    The district court erred in discounting the enhanced
    bioavailability in the ’330 Patent’s formulation as “a
    ‘difference in degree,’ not a difference in ‘kind,’” Dist. Ct.
    Op. at 774, for the clinical studies reported in the ’330
    Patent show 66% improved bioavailability. Particularly
    in the context of this invention, this is more than a trivial
    “degree.”
    4   Actavis states that Orexo did not argue to the dis-
    trict court that maintenance of the 4:1 ratio was an unex-
    pected result, and thus that this argument was waived.
    Actavis Br. at 61–62. Contrary to Actavis’ statement, the
    record shows Orexo’s arguments that “the ’330 invention’s
    novel structure and arrangement unexpectedly improves
    bioavailability over the closest prior art (Cairns / Subox-
    one), while maintaining the 4:1 buprenorphine to nalox-
    one ratio.” Orexo’s Resp. Dist. Ct. Br. at 53, ECF No. 200;
    
    id. at 54
     (“The 4:1 ratio is unexpected and relevant.”).
    OREXO AB   v. ACTAVIS ELIZABETH LLC                      17
    The district court also discounted Orexo’s evidence
    that Zubsolv is less susceptible to abuse than Suboxone,
    stating that “Orexo’s ‘real world evidence’ set forth above
    is not compelling or unrebutted,” and that “[t]he only
    objective evidence for this factor is that which was pre-
    sented to, and rejected by, the FDA.” 
    Id. at 776
    . Orexo
    stated that evidence of Zubsolv’s effectiveness in reducing
    abuse accumulated after FDA approval, and was present-
    ed to the district court. Although the weight of this
    evidence was disputed, the FDA deemed the product
    worthy of approval for the efficacy that was established in
    the clinical trials. It was established that this novel
    formulation enables reduced dosage and enhanced effica-
    cy in substitution therapy products, deterring abuse.
    On the entirety of the record, Actavis did not establish
    obviousness by clear and convincing evidence. The judg-
    ment of invalidity is reversed. We remand for appropriate
    further proceedings.
    REVERSED AND REMANDED