PTAB

IPR2018-01021

Cipla Ltd v. Alcon Research Ltd

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: High Concentration Olopatadine Ophthalmic Composition
  • Brief Description: The ’053 patent discloses aqueous ophthalmic solutions for treating ocular allergic conjunctivitis. The core of the invention is a stable, high-concentration formulation of the drug olopatadine (at least 0.67 w/v%) combined with specific stabilizing excipients, including polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), and a cyclodextrin derivative.

3. Grounds for Unpatentability

Ground 1: Claims 1-13 are obvious over Bhowmick in view of Yanni, Castillo, and Abelson

  • Prior Art Relied Upon: Bhowmick (WO 2008/015695), Yanni (a 1996 journal article), Castillo (Patent 6,995,186), and Abelson (a 2008 journal article).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that the combination of these references teaches all limitations of the challenged claims. Bhowmick taught using cyclodextrins to stabilize olopatadine solutions and prevent precipitation, a known problem. While Bhowmick disclosed concentrations up to 0.62 w/v%, Yanni taught that concentrations up to 1 w/v% provided superior, longer-lasting efficacy, motivating a person of ordinary skill in the art (POSA) to pursue concentrations meeting the claimed "at least 0.67 w/v%" limitation. To solve the known instability of such high-concentration solutions, a POSA would have looked to other known stabilizers for olopatadine. Castillo expressly taught using both PEG 400 (which falls within the claimed molecular weight range) and PVP to enhance the stability of olopatadine formulations.
    • Motivation to Combine: A POSA would combine these references to achieve the known goal of a stable, high-concentration olopatadine ophthalmic solution with enhanced efficacy. The motivation was to improve upon Bhowmick's base formulation by increasing the olopatadine concentration for better performance (as taught by Yanni) and incorporating well-known, proven stabilizers (PEG and PVP, as taught by Castillo) to ensure the resulting high-concentration product remained physically stable in solution.
    • Expectation of Success: A POSA would have had a reasonable expectation of success because all the components—olopatadine, cyclodextrins, PEG, and PVP—were well-known and commonly used in ophthalmic formulations. Combining them to enhance stability and drug loading was a predictable application of established formulation principles.

Ground 2: Claims 1-13 are obvious over Schneider in view of Hayakawa, Bhowmick, and Castillo

  • Prior Art Relied Upon: Schneider (Application # 2011/0082145), Hayakawa (Patent 5,641,805), Bhowmick (WO 2008/015695), and Castillo (Patent 6,995,186).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Schneider, as the primary reference, disclosed an aqueous ophthalmic solution containing olopatadine for treating allergic conjunctivitis at concentrations of "about 0.05%... 0.60% w/v, or higher." Schneider further taught that it is desirable to include compounds that enhance solubility, and listed PEG and PVP as optional excipients. To determine what "or higher" would mean, a POSA would have looked to Hayakawa, which taught stable olopatadine solutions with concentrations as high as 5 w/v%. This provided a clear motivation to increase the concentration beyond Schneider's 0.60% to the claimed level of at least 0.67 w/v%. The teachings of Bhowmick (using cyclodextrins) and Castillo (using PEG and PVP) provided the known methods to achieve the stability required for such a high-concentration formula.
    • Motivation to Combine: A POSA would combine Schneider with the other references to develop an optimized, high-concentration formulation. Schneider provided the blueprint for a modern olopatadine solution and explicitly suggested pursuing higher concentrations. Hayakawa demonstrated the feasibility and benefits of much higher concentrations. To enable such a formula, a POSA would have been motivated to incorporate the specific stabilizing agents taught by Bhowmick and Castillo, both of which addressed the known stability challenges of olopatadine.
    • Expectation of Success: Given that Schneider taught olopatadine solutions with the key excipients and suggested higher concentrations were possible, and Hayakawa confirmed the viability of very high concentrations, a POSA would have reasonably expected to successfully formulate a stable solution at 0.67 w/v%. The use of cyclodextrins, PEG, and PVP were common and predictable tools for achieving this outcome.

  • Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 3) based on the combination of Bhowmick in view of Castillo, Schneider, and Abelson, relying on similar arguments regarding the combination of known stabilizing excipients to achieve a high-concentration olopatadine formulation.

4. Key Claim Construction Positions

  • Petitioner argued that while several claim terms should be given their plain and ordinary meaning, specific attention should be paid to the preamble ("An aqueous ophthalmic solution for treatment...") and the concentration limitation ("at least 0.67 w/v % olopatadine dissolved in the solution"). Petitioner contended that even if the Board adopted the more limiting constructions from a related District Court case involving the parent ’154 patent, the asserted prior art combinations would still render all challenged claims obvious.

5. Key Technical Contentions (Beyond Claim Construction)

  • Petitioner dedicated a significant portion of its argument to challenging the patent's claim to priority. It argued that none of the challenged claims are entitled to the May 19, 2011, priority date of the '789 Provisional application. The basis for this argument was that the '789 Provisional allegedly fails to provide adequate written description support under §112 for key limitations, such as "hydroxypropyl-γ-cyclodextrin," and instead focuses exclusively on β-cyclodextrin derivatives. This argument, if successful, would establish an effective priority date of October 19, 2011, confirming the prior art status of certain references.

6. Arguments Regarding Discretionary Denial

  • Petitioner presented substantial arguments that discretionary denial would be inappropriate. Petitioner preemptively addressed an expected argument from the Patent Owner regarding a District Court decision that found the parent ’154 patent not invalid. Petitioner argued the PTAB should not be dissuaded because:
    • The District Court did not rule on the validity of the challenged ’053 patent.
    • The Board itself had previously instituted IPR on the parent ’154 patent based on similar art, demonstrating the merit of the challenge.
    • The District Court's analysis was flawed because it focused too heavily on the "preferred embodiments" of the prior art and on existing "commercial formulations," rather than considering the full scope of what the prior art taught a POSA.

7. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-13 of the ’053 patent as unpatentable under 35 U.S.C. §103.