DCT

1:13-cv-01674

Reckitt Benckiser Pharma Inc v. Watson Laboratories Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:13-cv-01674, D. Del., 08/04/2014
  • Venue Allegations: Plaintiffs allege venue is proper in the District of Delaware based on Defendants' incorporation in Delaware, their continuous and systematic business contacts within the district, and their previous submission to the jurisdiction of the court in other matters.
  • Core Dispute: Plaintiffs allege that Defendants' submission of an Abbreviated New Drug Application (ANDA) to seek approval for a generic version of Plaintiffs' Suboxone® sublingual film constitutes an act of patent infringement.
  • Technical Context: The technology concerns orally dissolvable films for delivering drugs, specifically for the treatment of opioid dependence, a formulation designed to provide therapeutic benefits while deterring abuse.
  • Key Procedural History: The complaint outlines a complex procedural history under the Hatch-Waxman Act, involving multiple Paragraph IV notice letters sent by Defendant Par to Plaintiffs between July 2013 and June 2014. Plaintiffs allege that the initial notices were premature and legally ineffective to trigger the 30-month statutory stay on FDA approval, contending that the operative notice was the one sent in March 2014 after the FDA had accepted the ANDA for substantive review.

Case Timeline

Date Event
2002-04-11 U.S. Patent No. 8,017,150 Priority Date
2002-06-07 U.S. Patent No. 8,603,514 Priority Date
2009-08-07 U.S. Patent No. 8,475,832 Priority Date
2010-08-30 FDA approves Plaintiffs' NDA for Suboxone® sublingual film
2011-09-13 U.S. Patent No. 8,017,150 Issues
2013-07-02 U.S. Patent No. 8,475,832 Issues
2013-07-08 Defendant Par sends first Paragraph IV Notice Letter
2013-12-10 U.S. Patent No. 8,603,514 Issues
2014-02-03 Defendant Par sends Paragraph IV Notice Letter regarding '514' Patent
2014-03-25 Defendant Par sends new Paragraph IV Notice Letter for all patents-in-suit
2014-04-08 Defendant Par sends another Paragraph IV Notice Letter adding new dosage strengths
2014-06-13 Defendant Par sends another Paragraph IV Notice Letter adding a new dosage strength
2014-08-04 Complaint Filing Date

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

U.S. Patent No. 8,475,832 - "Sublingual and Buccal Film Compositions"

  • Patent Identification: U.S. Patent No. 8,475,832, "Sublingual and Buccal Film Compositions", Issued July 2, 2013.

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of co-administering two drugs in a single oral dosage where one (an opioid agonist like buprenorphine) is intended for absorption in the mouth and the other (an antagonist like naloxone) is intended to pass through unabsorbed to prevent intravenous abuse (Compl., Ex. A, '832' Patent, col. 1:20-29). It also seeks to solve the problem of abuse associated with tablet forms, which can be removed from the mouth, crushed, and injected ('832 Patent, col. 1:55-63).
  • The Patented Solution: The invention is a self-supporting, orally dissolvable film that contains both the agonist and antagonist. The film includes a buffer system that controls the local pH in the mouth to a specific range. This pH manipulation is designed to "optimize" the absorption of buprenorphine while simultaneously "inhibiting" the absorption of naloxone, which remains ionized and thus poorly absorbed through the oral mucosa ('832 Patent, col. 11:19-39). The film's adhesive properties also make it difficult to remove once placed, further deterring abuse ('832 Patent, col. 2:1-4).
  • Technical Importance: This approach allows for a drug delivery system for opioid dependence that is bioequivalent to existing tablets but has a lower potential for abuse and diversion ('832 Patent, col. 2:55-63).

Key Claims at a Glance

  • The complaint asserts infringement of one or more unspecified claims (Compl. ¶58). Independent claim 1 is representative.
  • Claim 1 requires:
    • A film dosage composition comprising:
    • a. A polymeric carrier matrix;
    • b. A therapeutically effective amount of buprenorphine or a pharmaceutically acceptable salt thereof;
    • c. A therapeutically effective amount of naloxone or a pharmaceutically acceptable salt thereof; and
    • d. A buffer in an amount to provide a local pH for said composition of a value sufficient to optimize absorption of said buprenorphine, wherein said local pH is from about 3 to about 3.5 in the presence of saliva.

U.S. Patent No. 8,017,150 - "Polyethylene Oxide-Based Films and Drug Delivery Systems Made Therefrom"

  • Patent Identification: U.S. Patent No. 8,017,150, "Polyethylene Oxide-Based Films and Drug Delivery Systems Made Therefrom", Issued September 13, 2011.

The Invention Explained

  • Problem Addressed: The patent's background describes how conventional methods for making drug-containing films often result in non-uniformity due to the "aggregation or conglomeration of particles" during the drying process (Compl., Ex. B, '150' Patent, col. 2:7-9). This non-uniformity prevents accurate and consistent dosing. Furthermore, conventional high-temperature drying can create a "skin" on the film's surface, which traps moisture and leads to an uneven, rippled final product ('150 Patent, col. 3:30-50).
  • The Patented Solution: The invention claims a water-soluble film with a specific polymer composition based on polyethylene oxide (PEO), optionally blended with hydrophilic cellulosic polymers. This composition is processed using a controlled, rapid drying method, such as applying heat to the bottom of the film, which prevents skin formation and maintains the uniform distribution of the active ingredient ('150 Patent, col. 4:5-14). The result is a film with a non-self-aggregating uniform heterogeneity, defined as having no more than a 10% variance of the active agent per unit area ('150 Patent, Abstract).
  • Technical Importance: This invention provides a method to manufacture uniform, rapidly dissolving oral films, enabling them to serve as a reliable dosage form for pharmaceuticals ('150 Patent, col. 4:5-9).

Key Claims at a Glance

  • The complaint asserts infringement of one or more unspecified claims (Compl. ¶64). Independent claim 1 is representative.
  • Claim 1 requires:
    • A mucosally-adhesive water-soluble film product, which includes:
    • an analgesic opiate pharmaceutical active; and
    • at least one water-soluble polymer component including polyethylene oxide in combination with a hydrophilic cellulosic polymer;
    • wherein the component includes greater than 75% polyethylene oxide and up to 25% hydrophilic cellulosic polymer;
    • wherein the polyethylene oxide includes specific low molecular weight (100k-300k) and higher molecular weight (600k-900k) ranges; and
    • wherein the polyethylene oxide of low molecular weight is about 60% or more of the polymer component.

U.S. Patent No. 8,603,514 - "Uniform Films for Rapid Dissolve Dosage Form Incorporating Taste-Masking Compositions"

  • Patent Identification: U.S. Patent No. 8,603,514, "Uniform Films for Rapid Dissolve Dosage Form Incorporating Taste-Masking Compositions", Issued December 10, 2013.

Technology Synopsis

This patent focuses on achieving uniform distribution of active ingredients within a rapidly dissolving film when those ingredients have been coated for taste-masking or controlled-release purposes (Compl., Ex. C, '514 Patent, col. 1:18-24). The invention describes specific film-forming matrices and controlled drying processes that prevent the coated particles from aggregating, ensuring that each unit dose cut from a larger film sheet contains a consistent and accurate amount of the active drug ('514 Patent, Abstract).

Asserted Claims

The complaint asserts infringement of one or more unspecified claims (Compl. ¶70).

Accused Features

The accused product is Defendants' generic buprenorphine hydrochloride and naloxone hydrochloride sublingual film, which the complaint alleges is covered by one or more claims of the '514 Patent (Compl. ¶¶33, 70).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Defendants' generic version of buprenorphine hydrochloride and naloxone hydrochloride sublingual film, for which Defendant Par submitted ANDA No. 20-5854 to the FDA (Compl. ¶¶33, 59).

Functionality and Market Context

The accused product is a sublingual film intended for the maintenance treatment of opioid dependence (Compl. ¶38). It is designed as a generic equivalent to Plaintiffs' Suboxone® sublingual film and purports to be bioequivalent (Compl. ¶34). The complaint alleges that the product was designed by Defendant IGX and incorporates its VersaFilmTM drug delivery technology (Compl. ¶¶36-37). The product is the subject of an ANDA filing, which is a statutory act of infringement under the Hatch-Waxman Act, allowing the patent holder to sue before the generic product enters the market (Compl. ¶¶23-28, 59).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not provide a detailed, element-by-element infringement analysis. The allegations are based on Defendants' filing of an ANDA, which under 35 U.S.C. § 271(e)(2) is an act of infringement if the product described in the ANDA, were it to be commercially manufactured and sold, would infringe the patents-in-suit (Compl. ¶¶59, 65, 71). The following charts summarize the infringement theory based on the general description of the accused product.

'832 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A film dosage composition comprising: The accused product is a sublingual film dosage form. ¶33 col. 11:59-60
a. A polymeric carrier matrix; As a film, the accused product necessarily contains a polymeric carrier matrix, and is alleged to use VersaFilmTM technology. ¶33, ¶37 col. 11:61-62
b. A therapeutically effective amount of buprenorphine or a pharmaceutically acceptable salt thereof; The accused product contains buprenorphine hydrochloride. ¶33, ¶50 col. 11:63-64
c. A therapeutically effective amount of naloxone or a pharmaceutically acceptable salt thereof; and The accused product contains naloxone hydrochloride. ¶33, ¶50 col. 11:65-66
d. A buffer in an amount to provide a local pH for said composition ... from about 3 to about 3.5 in the presence of saliva. The complaint does not specify the buffering agent or resulting pH of the accused product but alleges that the product is covered by the claims. ¶58 col. 11:67-col. 12:4

'150 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A mucosally-adhesive water-soluble film product, which includes: The accused product is a sublingual film. ¶33 col. 4:26-27
an analgesic opiate pharmaceutical active; and The accused product contains buprenorphine hydrochloride, an opioid partial agonist. ¶33 col. 4:26
at least one water-soluble polymer component including polyethylene oxide in combination with a hydrophilic cellulosic polymer; The complaint does not specify the polymer composition of the accused product but alleges that the product is covered by the claims. ¶64 col. 4:27-30
wherein: the water-soluble polymer component includes greater than 75% polyethylene oxide and up to 25% hydrophilic cellulosic polymer; The complaint does not specify the polymer ratios of the accused product. ¶64 col. 4:31-33
the polyethylene oxide includes one or more low molecular weight polyethylene oxides and one or more higher molecular weight polyethylene oxides... The complaint does not specify the molecular weights of the polymers in the accused product. ¶64 col. 4:34-40
the polyethylene oxide of low molecular weight is about 60% or more in the polymer component. The complaint does not specify the relative amount of low molecular weight PEO in the accused product. ¶64 col. 4:41-43

Identified Points of Contention

  • Scope Questions: A primary question for the '832 Patent will be the interpretation of "a local pH ... from about 3 to about 3.5." The scope of the term "about" will be critical, as will the method for measuring the "local pH" created by the film in the presence of saliva.
  • Technical Questions: The core of the dispute will likely turn on the specific formulation detailed in the Defendants' ANDA, which is not public. For the '832 Patent, what evidence will show that the accused product's excipients function as a "buffer" to achieve the claimed pH? For the '150 Patent, does the accused product's polymer matrix contain the specific combination of polyethylene oxide and hydrophilic cellulosic polymer, in the claimed molecular weight ranges and ratios, required by the claim?

V. Key Claim Terms for Construction

Term: "a local pH ... from about 3 to about 3.5" ('832 Patent, Claim 1)

  • Context and Importance: This term is the central technical feature of the '832 Patent's invention, which relies on precise pH control to achieve differential absorption of the two active ingredients. Infringement will depend entirely on whether the accused product creates this specific chemical environment. Practitioners may focus on this term because its boundaries, defined by "about," and the methodology for its measurement ("local pH... in the presence of saliva") are not explicitly defined in the claim and may be subject to significant debate.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification describes the desired pH range more broadly in several places, such as "in the range of about 2 to about 4" and "more preferably about 3 to about 4" ('832 Patent, col. 12:30-32). This language may be used to argue that "about 3 to about 3.5" should not be read as a rigid range.
    • Evidence for a Narrower Interpretation: The specification repeatedly identifies a pH of 3.5 as "most preferably the local pH" ('832 Patent, col. 12:34). Furthermore, experimental data in the patent compares results at pH 3.5, 5.5, and 6.5, with the data suggesting that the pH 3.5 formulation provides results most bioequivalent to the Suboxone® tablet ('832 Patent, Tables 10-12). This could support a narrower construction where "about" does not extend far from the 3.0-3.5 range.

Term: "water-soluble polymer component including polyethylene oxide in combination with a hydrophilic cellulosic polymer" ('150 Patent, Claim 1)

  • Context and Importance: The infringement analysis for the '150 Patent will depend on whether the accused product contains this specific combination of polymers. The term defines the fundamental composition of the film's matrix.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification lists numerous water-soluble polymers, suggesting a wide array of possibilities, though the claims are more specific ('150 Patent, col. 15:43-58). A defendant might argue that its film, while functional, uses a different combination of polymers that falls outside the claim scope.
    • Evidence for a Narrower Interpretation: The claim language itself is quite specific, requiring both PEO and a hydrophilic cellulosic polymer. The detailed description and examples may provide a technical rationale for why this specific combination is necessary to achieve the desired properties of fast dissolution and tear resistance, supporting a construction that requires the presence of both polymer types ('150 Patent, col. 18:14-23).

VI. Other Allegations

Indirect Infringement

The complaint alleges that Defendant IGX, the technology developer, was "actively involved in the preparation" and "prosecution before the FDA of ANDA No. 20-5854" (Compl. ¶60). It further alleges that IGX's "active assistance and involvement with the submission of ANDA No. 20-5854 is an act of infringement" (Compl. ¶61). This appears to be a basis for holding the non-ANDA applicant liable for infringement under § 271(e)(2).

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

  • A core issue will be one of chemical equivalence: does the specific formulation of the accused generic film, as disclosed in the confidential ANDA, meet the precise quantitative limitations of the asserted claims? This will involve detailed factual analysis of its polymer composition, molecular weights, and ratios for the '150 Patent, and its buffering capacity and resulting local pH for the '832 Patent.
  • A key threshold question will be one of procedural timing: which of the multiple Paragraph IV notice letters sent by Defendants was legally effective under the Hatch-Waxman Act? The court's determination of this issue could impact the timing of the statutory 30-month stay of FDA approval, a matter of significant commercial importance to both the brand and generic manufacturers.
  • A central question of claim scope will be the construction of "local pH... from about 3 to about 3.5." The interpretation of this term will likely determine the outcome of infringement for the '832 patent, as it represents the core of the patented solution to the problem of differential drug absorption.