PTAB

IPR2015-00988

Coalition for Affordable Drugs II LLC v. Cosmo Technologies Ltd

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1. Case Identification

2. Patent Overview

  • Title: Mesalazine Controlled Release Oral Pharmaceutical Compositions
  • Brief Description: The ’720 patent describes controlled-release oral pharmaceutical compositions for treating inflammatory bowel disease. The compositions comprise the active ingredient 5-amino-salicylic acid (5-ASA) within a dual-matrix system, consisting of an inner lipophilic matrix dispersed within an outer hydrophilic matrix, to ensure targeted delivery to the colon.

3. Grounds for Unpatentability

Ground 1: Obviousness over Leslie - Claims 1-4 are obvious over Leslie.

  • Prior Art Relied Upon: Leslie (Patent 3,965,256).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Leslie taught every element of the challenged claims in a single reference. Leslie disclosed controlled-release pharmaceutical compositions comprising an inner lipophilic matrix (cetyl alcohol, which Petitioner contended is a "wax" under the proper claim construction) and an outer hydrophilic matrix (hydroxyl-alkyl cellulose). Petitioner asserted that Leslie also explicitly taught that the active ingredient (API) can be "divided among both agents," thereby being dispersed in both matrices. Furthermore, Leslie taught formulating these compositions into tablets with high API concentrations (e.g., 80% and 82%), meeting all limitations of independent claim 1 and dependent claims 2-4.
    • Motivation to Combine (for §103 grounds): As a single-reference ground, the motivation was to apply Leslie's established teachings to the known therapeutic agent 5-ASA. Petitioner argued that a person of ordinary skill in the art (POSA) seeking to improve 5-ASA formulations would have been motivated to use Leslie's system, as it addressed the same controlled-release objectives. This motivation was strengthened because Leslie expressly identified "salicylate and acetyl-salicylate compounds" as a preferred genus of APIs, making 5-ASA an obvious species for use in the disclosed system.
    • Expectation of Success: A POSA would have had a reasonable expectation of success in formulating 5-ASA according to Leslie's teachings because the methods were well-defined and their application to a known salicylate compound was predictable.

Ground 2: Obviousness over Leslie in view of Rhodes - Claims 1-4 are obvious over Leslie in further view of Rhodes.

  • Prior Art Relied Upon: Leslie (Patent 3,965,256) and Rhodes (Patent 5,541,170).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Leslie provided the core dual-matrix formulation technology, as detailed in Ground 1. Rhodes provided the specific teaching of using high concentrations of 5-ASA (a composition with nearly 83% API) and, importantly, demonstrated its successful clinical results in treating colonic disorders. The combination of Leslie's matrix system with Rhodes' high-dose 5-ASA met all claim limitations.
    • Motivation to Combine: A POSA would have been motivated to combine the references to overcome known deficiencies in prior art 5-ASA formulations, such as inconsistent colonic delivery caused by pH-dependent release mechanisms. Rhodes showed the therapeutic benefit of a high-dose 5-ASA composition, while Leslie provided a robust, pH-independent matrix delivery system. A POSA would combine Leslie's superior delivery platform with Rhodes' clinically proven high-dose API to create a more reliable and effective treatment.
    • Expectation of Success: A POSA would have had a reasonable expectation of success because Leslie's matrix system was taught to be effective for high-dose APIs, and Rhodes demonstrated that high-dose 5-ASA was safe and effective. Combining the two was a predictable implementation of known technologies to achieve a desired result.

Ground 3: Obviousness over Groenendaal in view of Leslie - Claims 1-4 are obvious over Groenendaal in view of Leslie.

  • Prior Art Relied Upon: Groenendaal (EP 0 375 063) and Leslie (Patent 3,965,256).
  • Core Argument for this Ground:
    • Prior Art Mapping: Leslie again supplied the core teachings of a dual lipophilic/hydrophilic matrix system. Groenendaal specifically taught controlled-release granulates of 5-ASA with a high API content, disclosing a preferred range of 20-90% by weight, which overlaps with and extends to the upper end of the ’720 patent’s claimed range (80-95%). Groenendaal also provided valuable dissolution data for its high-concentration 5-ASA formulations.
    • Motivation to Combine: The motivation was to improve upon existing 5-ASA delivery systems. A POSA would have recognized the benefits of the high-dose 5-ASA formulations disclosed in Groenendaal and sought to formulate them using a reliable delivery mechanism. Leslie's pH-independent matrix system provided an obvious and advantageous solution for ensuring that the high-dose 5-ASA from Groenendaal reached its therapeutic target in the lower intestine.
    • Expectation of Success: A POSA would have reasonably expected to successfully formulate Groenendaal's high-dose 5-ASA using Leslie's matrix system. The successful examples in Leslie, combined with the dissolution data in Groenendaal, would have provided a high degree of confidence that the combination would work for its intended purpose.

4. Key Claim Construction Positions

  • "Inner lipophilic matrix" / "Outer hydrophilic matrix": Petitioner construed these terms to mean separate matrix structures with distinct physical characteristics (lipophilic or hydrophilic), a structure they argued was clearly taught by Leslie’s two-component system of cetyl alcohol and hydroxyl-alkyl cellulose.
  • "Wherein the active ingredient is dispersed both in the lipophilic matrix and in the hydrophilic matrix": Petitioner construed this to mean the API is sufficiently mixed to be incorporated into both matrices. This construction was central to the argument that Leslie met this limitation by explicitly teaching that the API can be "divided among both agents" (the lipophilic alcohol and the hydrophilic cellulose components).
  • Markush Groups (e.g., "waxes"): Petitioner argued for a construction consistent with the understanding of a POSA, contending that the term "waxes" would encompass substances like cetyl alcohol, a key lipophilic component in Leslie that possesses waxy properties and a melting point below 90°C.

7. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-4 of Patent 6,773,720 as unpatentable.