DCT

3:19-cv-13348

Senju Pharmaceutical Co Ltd v. Aurobindo Pharma USA Inc

Log In
Key Events
Complaint
complaint Intelligence

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:19-cv-13348, D.N.J., 06/03/2019
  • Venue Allegations: Venue is alleged to be proper against Aurobindo USA based on its principal place of business in the District of New Jersey. Venue is alleged against Aurobindo India on the basis that it is a foreign corporation subject to personal jurisdiction in the district.
  • Core Dispute: Plaintiffs allege that Defendants’ filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiffs’ Prolensa® ophthalmic solution constitutes infringement of nine U.S. patents.
  • Technical Context: The technology involves aqueous ophthalmic formulations of bromfenac, a non-steroidal anti-inflammatory drug (NSAID) used to treat ocular pain and inflammation, particularly following cataract surgery.
  • Key Procedural History: The action was triggered by Defendants' submission of ANDA No. 212964 seeking FDA approval to market a generic 0.07% bromfenac ophthalmic solution and Plaintiffs' receipt of a corresponding notice letter on April 19, 2019. All nine asserted patents are listed in the FDA's "Orange Book" for Prolensa®. Five of the asserted patents (’431, ’290, ’131, ’813, ’606) have previously survived inter partes review (IPR) proceedings, with their claims confirmed as patentable, a fact that may be relevant to future validity challenges.

Case Timeline

Date Event
2003-01-21 Priority Date for '431, '290, '131, '813, '606 Patents
2011-10-12 Priority Date for ’609, ’220, ’277, ’958 Patents
2012-03-06 '431 Patent Issued
2013-04-05 FDA Approved NDA No. 203168 for Prolensa®
2014-03-11 '290 Patent Issued
2014-06-17 '131 Patent Issued
2014-10-28 '813 Patent Issued
2015-01-06 '606 Patent Issued
2015-09-29 '609 Patent Issued
2016-12-13 '220 Patent Issued
2017-02-07 '277 Patent Issued
2018-10-02 '958 Patent Issued
2019-04-19 Plaintiffs Received Aurobindo's Notice Letter for ANDA No. 212964
2019-06-03 Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 8,129,431 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

The Invention Explained

  • Problem Addressed: The patent addresses the problem that preservatives commonly used in ophthalmic solutions, such as benzalkonium chloride, can lose their effectiveness when combined with acidic non-steroidal anti-inflammatory drugs (NSAIDs) like bromfenac, because the preservative and drug form complexes ('431 Patent, col. 2:1-11).
  • The Patented Solution: The invention introduces a stabilizing agent—specifically an alkyl aryl polyether alcohol type polymer like tyloxapol or a polyethylene glycol fatty acid ester—into the aqueous bromfenac formulation. This agent is described as preventing the loss of preservative effect and inhibiting the degradation of the bromfenac active ingredient over time ('431 Patent, abstract; '431 Patent, col. 2:35-50).
  • Technical Importance: This solution enabled the creation of a stable, commercially viable, multi-dose ophthalmic formulation of bromfenac that retains its preservative efficacy, which is critical for patient safety and product shelf-life ('431 Patent, col. 2:51-54).

Key Claims at a Glance

  • The complaint asserts at least one claim of the '431 patent (Compl. ¶38). Independent claim 1 is representative.
  • The essential elements of independent claim 1 are:
    • An aqueous liquid preparation consisting essentially of:
    • A first component: 2-amino-3-(4-bromobenzoyl)phenylacetic acid or a salt or hydrate thereof; and
    • A second component: tyloxapol.
    • The preparation is formulated for ophthalmic administration.
    • If a quaternary ammonium compound is included, it is benzalkonium chloride.

U.S. Patent No. 8,669,290 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

The Invention Explained

  • Problem Addressed: As a divisional of the '431 patent, the '290 patent addresses the same technical challenge: the instability of aqueous bromfenac solutions and the reduced efficacy of preservatives like benzalkonium chloride when combined with bromfenac ('290 Patent, col. 2:1-11).
  • The Patented Solution: The solution is also the same: incorporating a stabilizing agent, such as tyloxapol, into the formulation to prevent both drug degradation and loss of preservative effect ('290 Patent, abstract; '290 Patent, col. 2:35-50).
  • Technical Importance: The invention provides a basis for a stable, preserved, multi-dose bromfenac eye drop suitable for treating ocular inflammation ('290 Patent, col. 2:51-54).

Key Claims at a Glance

  • The complaint asserts at least one claim of the '290 patent (Compl. ¶49). Independent claim 1 is representative.
  • The essential elements of independent claim 1 are:
    • A stable aqueous liquid preparation comprising:
    • A first component: 2-amino-3-(4-bromobenzoyl)phenylacetic acid or a salt/hydrate thereof, which is the sole pharmaceutical active ingredient.
    • A second component: tyloxapol, present in an amount sufficient to stabilize the first component.
    • The preparation is formulated for ophthalmic administration.

U.S. Patent No. 8,754,131 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

  • Technology Synopsis: As a continuation of the '431 and '290 patents, this patent covers stable aqueous bromfenac formulations containing tyloxapol as a stabilizer. The claims add a functional requirement that the preparation is characterized by retaining a specific percentage of the active ingredient after a period of storage ('131 Patent, claim 7).
  • Asserted Claims: At least one claim is asserted (Compl. ¶60).
  • Accused Features: The accused product is Aurobindo's generic bromfenac ophthalmic solution, which is alleged to infringe by virtue of its filing with the FDA (Compl. ¶60).

U.S. Patent No. 8,871,813 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenyl-Acetic Acid”

  • Technology Synopsis: This patent, also in the same family, claims specific stable formulations of bromfenac containing tyloxapol and a list of other excipients, such as boric acid, sodium tetraborate, and polyvinylpyrrolidone ('813 Patent, claim 13).
  • Asserted Claims: At least one claim is asserted (Compl. ¶71).
  • Accused Features: The act of submitting ANDA No. 212964 for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶71).

U.S. Patent No. 8,927,606 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

  • Technology Synopsis: This patent continues the same technology, with claims directed to methods of treating inflammatory eye diseases by administering the stable bromfenac/tyloxapol formulations ('606 Patent, claim 1). The claims also recite the formulation's stability characteristics.
  • Asserted Claims: At least one claim is asserted (Compl. ¶82).
  • Accused Features: The filing of the ANDA for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶82).

U.S. Patent No. 9,144,609 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

  • Technology Synopsis: This patent relates to a different technical approach for improving bromfenac eye drops. It describes a non-preserved formulation of bromfenac, packaged as a unit-dose, addressing the needs of patients sensitive to preservatives ('609 Patent, claim 4).
  • Asserted Claims: At least one claim is asserted (Compl. ¶93).
  • Accused Features: The filing of the ANDA for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶93).

U.S. Patent No. 9,517,220 - “Bromfenac Bioavailability”

  • Technology Synopsis: This patent discloses methods for enhancing the penetration of bromfenac into ocular tissue by formulating the solution at a specific pH range (pH ≥6.0 and <8.3). This allows for a lower concentration of bromfenac while maintaining efficacy, which is presented as an advantage ('220 Patent, abstract).
  • Asserted Claims: At least one claim is asserted (Compl. ¶104).
  • Accused Features: The filing of the ANDA for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶104).

U.S. Patent No. 9,561,277 - “Aqueous Liquid Preparation Containing 2-Amino-3-(4-Bromobenzoyl)Phenylacetic Acid”

  • Technology Synopsis: This patent is another continuation in the '431 family, claiming specific stable aqueous formulations of bromfenac that contain tyloxapol as a stabilizer ('277 Patent, claim 1).
  • Asserted Claims: At least one claim is asserted (Compl. ¶115).
  • Accused Features: The filing of the ANDA for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶115).

U.S. Patent No. 10,085,958 - “Bromfenac Bioavailability”

  • Technology Synopsis: As a continuation of the '220 patent, this patent covers aqueous compositions of bromfenac with a specific pH range (between ≥6.0 and <8.0) and povidone as an excipient, designed to enhance bioavailability ('958 Patent, claim 1).
  • Asserted Claims: At least one claim is asserted (Compl. ¶126).
  • Accused Features: The filing of the ANDA for a generic bromfenac ophthalmic solution is the accused act of infringement (Compl. ¶126).

III. The Accused Instrumentality

Product Identification

Defendants' "generic bromfenac ophthalmic solution (0.07%)" for which ANDA No. 212964 was filed with the U.S. Food and Drug Administration (FDA) (Compl. ¶6; Compl. ¶31).

Functionality and Market Context

The accused product is intended to be a generic version of Prolensa®, a once-daily ophthalmic solution used for the treatment of postoperative inflammation and reduction of ocular pain in patients who have had cataract surgery (Compl. ¶32; '958 Patent, col. 1:11-16). The complaint alleges that the formulation of the accused product is "the same, or substantially the same, as Prolensa®" (Compl. ¶36). The complaint does not provide specific details about the excipients or pH of the accused product, as that information is contained within the confidential ANDA submission.

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint alleges infringement under 35 U.S.C. § 271(e)(2), which defines the submission of an ANDA for a drug claimed in a patent as a technical act of infringement to create federal court jurisdiction to resolve the dispute before the generic product enters the market (Compl. ¶38). The complaint does not provide a detailed, element-by-element infringement analysis. The infringement theory rests on the allegation that Defendants' product is a generic version of Prolensa® and that the patents-in-suit are listed in the Orange Book for Prolensa®, creating an inference that the generic product will infringe (Compl. ¶29; Compl. ¶32; Compl. ¶36).

'431 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
An aqueous liquid preparation consisting essentially of: (a) a first component, and (b) a second component; wherein the first component is 2-amino-3-(4-bromobenzoyl)phenylaceticacid or a pharmacologically acceptable salt thereof or a hydrate thereof... The complaint alleges that Defendants' ANDA product is an aqueous ophthalmic solution of bromfenac intended as a generic version of Prolensa®. ¶32; ¶36 col. 4:15-24
and wherein the second component is tyloxapol... The complaint alleges that the submission of ANDA No. 212964 for a product intended to be a generic version of Prolensa® constitutes an act of infringement of the '431 patent. ¶38; ¶39 col. 4:47-53
wherein said liquid preparation is formulated for ophthalmic administration... The accused product is an ophthalmic solution for which Defendants are seeking FDA approval. ¶6; ¶32 col. 4:6-14

'290 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A stable aqueous liquid preparation comprising: (a) a first component... wherein the first component is 2-amino-3-(4-bromobenzoyl)phenylacetic acid or a pharmacologically acceptable salt thereof or a hydrate thereof... and is the sole pharmaceutical active ingredient... The complaint alleges that Defendants' ANDA product is an aqueous ophthalmic solution of bromfenac intended as a generic version of Prolensa®. ¶32; ¶36 col. 4:15-24
and (b) a second component; wherein the second component is tyloxapol and is present in said liquid preparation in an amount sufficient to stabilize said first component... The complaint alleges that the ANDA submission is an act of infringement, and that the resulting product, if marketed, would infringe the '290 patent. ¶49; ¶50 col. 2:35-50
and wherein said stable liquid preparation is formulated for ophthalmic administration. The accused product is an ophthalmic solution for which Defendants are seeking FDA approval. ¶6; ¶32 col. 4:6-14

Identified Points of Contention

  • Formulation Identity Questions: A primary set of factual questions will concern the precise composition of Defendants' proposed generic product. Does it contain tyloxapol, as required by claims in the '431 patent family? Does its pH fall within the ranges claimed by the '958 patent family? The answers, contained in the ANDA, will be central to the infringement analysis.
  • Scope Questions: For the '431 patent, a key legal question may be the interpretation of the term "consisting essentially of." The court will have to determine whether any unlisted excipients in the accused product materially alter the basic and novel properties of the claimed invention, namely stability and preservative efficacy.
  • Functional Limitation Questions: For the '290 patent, a point of contention may be the meaning of "an amount sufficient to stabilize." This raises the question of what benchmark or degree of stability is required to meet this limitation, and what evidence is needed to prove it.

V. Key Claim Terms for Construction

The Term: "consisting essentially of" (from '431 Patent, claim 1)

  • Context and Importance: This transitional phrase is a term of art that restricts the scope of the claim to the specified ingredients and those that do not "materially affect the basic and novel properties of the invention." Its construction is critical because if Defendants' formulation contains additional excipients (e.g., other surfactants or stabilizers), the infringement analysis will turn on whether those excipients have a material effect.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification discloses that numerous other additives, such as buffers (boric acid, borax), thickeners (polyvinylpyrrolidone), and chelating agents (sodium edetate), may be added to the formulation, which may support an argument that these common excipients do not materially affect the invention's core properties ('431 Patent, col. 6:11-35).
    • Evidence for a Narrower Interpretation: The patent identifies the core problem as the interaction between the NSAID and the preservative, and the solution as the specific addition of tyloxapol or a similar polymer ('431 Patent, col. 2:1-11; '431 Patent, col. 2:35-50). A party could argue that the "basic and novel" property is this specific stabilizing interaction, and any other substance that affects it, even slightly, would be a material alteration.

The Term: "an amount sufficient to stabilize" (from '290 Patent, claim 1)

  • Context and Importance: This functional language defines the quantity of the second component (tyloxapol) by its result rather than a specific numerical range. Practitioners may focus on this term because its interpretation will determine the evidentiary burden for proving infringement. The dispute will likely center on what level of stability is "sufficient" and how it should be measured.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A plaintiff might argue that any statistically significant improvement in stability compared to a formulation without tyloxapol is "sufficient," and that the term does not require meeting a specific commercial or regulatory threshold.
    • Evidence for a Narrower Interpretation: The '431 patent (parent to the '290 patent) provides experimental data showing formulations with tyloxapol retaining over 89% of the active ingredient after 4 weeks at 60°C ('431 Patent, col. 7, Table 1). A defendant could argue that "sufficient" should be interpreted in light of these examples, requiring a high degree of stability that provides a meaningful advantage over the prior art.

VI. Other Allegations

  • Indirect Infringement: The complaint includes general allegations of contributory and induced infringement for all asserted patents (e.g., Compl. ¶40; Compl. ¶51). No specific facts are alleged to support these claims, which are likely included as a standard pleading measure.
  • Willful Infringement: The complaint does not use the word "willful." However, it requests a declaration that the case is "exceptional" under 35 U.S.C. § 285 and seeks an award of attorney's fees (Prayer for Relief, ¶13). The complaint alleges that Defendants’ notice letter "does not allege meritorious non-infringement defenses" for any of the asserted patents, which could form part of a basis for an exceptional case argument (Compl. ¶35).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central question of fact will be one of formulation identity: does the Defendants' proposed generic product, as described in its confidential ANDA, contain the specific excipients (e.g., tyloxapol) and operate at the specific pH levels required by the asserted claims, or does it utilize a different, non-infringing formulation design?
  • A core issue of claim construction will be one of scope: for the '431 patent family, can the term "consisting essentially of" be interpreted to read on a formulation containing additional, unlisted excipients, or does their presence place the product outside the claim's boundary?
  • A key strategic question will revolve around validity: given that five of the asserted patents have already survived IPR challenges, a significant hurdle for Defendants will be to present evidence of invalidity that is sufficiently new or persuasive to overcome the patents' resilience before the Patent Trial and Appeal Board.