PTAB

IPR2017-00380

Merck Sharp & Dohme Corp v. Wyeth LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Formulations of Polysaccharide-Protein Conjugates
  • Brief Description: The ’999 patent discloses immunogenic formulations, such as vaccines, containing polysaccharide-protein conjugates. The invention centers on formulations that include an aluminum salt and a buffer within a siliconized container, which are asserted to inhibit the known problem of protein aggregation induced by silicone oil lubricants.

3. Grounds for Unpatentability

Ground 1: Obviousness over Prevenar 2005 and Chiron 2003 - Claims 1-6, 10-11, 14, and 17-20 are obvious over Prevenar 2005 in view of Chiron 2003 and the general knowledge of a POSITA.

  • Prior Art Relied Upon: Prevenar 2005 (Summary of Product Characteristics for Patent Owner's 7-valent Prevenar vaccine), Chiron 2003 (WO 03/009869).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Prevenar 2005, a commercially available vaccine from the Patent Owner, disclosed nearly every element of independent claim 1. It was a pneumococcal polysaccharide-protein conjugate vaccine containing an aluminum phosphate adjuvant and sodium chloride, provided in a pre-filled glass syringe, which a person of ordinary skill in the art (POSITA) would have known was siliconized. The only missing element was a buffer. Chiron 2003, which is directed to similar aluminum-adjuvanted conjugate vaccines, explicitly taught adding a buffer (specifically, histidine) to enhance pH stability and antigen stability. Dependent claims reciting specific surfactants (polysorbate 80), conjugates (7-valent pneumococcal), and aluminum salts (aluminum phosphate) were also taught by the combination of Prevenar 2005 and Chiron 2003. The claimed property of inhibiting silicone-induced aggregation was argued to be an inherent property of the prior art formulation, particularly given the known stabilizing effects of adsorbing conjugates onto an aluminum phosphate adjuvant, a feature present in Prevenar 2005.
    • Motivation to Combine: A POSITA would combine the teachings because adding a buffer was a routine and well-understood method for optimizing vaccine formulations. Chiron 2003 provided the explicit rationale to add a histidine buffer to a formulation like Prevenar 2005 (which lacked a buffer) to improve its stability, a known goal for vaccine developers.
    • Expectation of Success: A POSITA would have had a high expectation of success. Both references dealt with the same technical field of aluminum-adjuvanted conjugate vaccines, and incorporating a standard component like a buffer for its known stabilizing properties was a predictable and routine step in formulation development.

Ground 2: Obviousness over Prevenar 2005, Chiron 2003, and Pena 2004 - Claim 18 is obvious over Prevenar 2005 in view of Chiron 2003 and Pena 2004.

  • Prior Art Relied Upon: Prevenar 2005 (product summary), Chiron 2003 (WO 03/009869), and Pena 2004 (a 2004 journal article reviewing pneumococcal vaccines).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground specifically targeted claim 18, which recites a 13-valent pneumococcal conjugate formulation. Petitioner leveraged the same core combination from Ground 1, where Prevenar 2005 and Chiron 2003 established the base formulation of claim 1. The additional reference, Pena 2004, was introduced to demonstrate that expanding the 7-valent Prevenar vaccine to a 13-valent version was an obvious and predictable step. Pena 2004 explicitly described the ongoing development and natural progression from the 7-valent Prevenar vaccine to 9-valent, 11-valent, and ultimately 13-valent versions, identifying the specific serotypes that would be added.
    • Motivation to Combine: The motivation was to increase the serotype coverage of the vaccine to provide broader protection against pneumococcal disease. Petitioner argued this was a well-established and natural progression in multivalent vaccine development. Pena 2004 confirmed that this exact progression was already in advanced stages of study for the Prevenar vaccine, making the expansion to 13 serotypes an obvious design choice for a POSITA.
    • Expectation of Success: A POSITA would have reasonably expected success in creating a stable 13-valent formulation. The underlying formulation technology was the same as the 7-valent version, and the expansion of serotypes was a known strategy in the field. Pena 2004’s disclosure of ongoing studies confirmed the feasibility of this progression.

4. Key Claim Construction Positions

  • "the formulation . . . inhibits aggregation induced by the siliconized container means": Petitioner argued this phrase recites a property of the formulation as a whole and does not require that any specific ingredient listed in the claim (e.g., the aluminum salt) be the sole agent responsible for the inhibition. This construction supports the argument that the prior art formulation inherently possessed this property, even if not explicitly recognized, and allows for other components (like surfactants taught in dependent claims) to contribute to the effect.
  • "polysaccharide": Petitioner proposed this term be given the broad, explicit definition provided in the ’999 patent’s specification, which includes not only traditional polysaccharides but also shorter oligosaccharides and other saccharide elements commonly used in vaccine arts.
  • "container means": Petitioner asserted this term should be construed according to its explicit definition in the specification, which encompasses a wide range of containers used for drug formulation, storage, and administration, including vials, stoppers, and the pre-filled syringes disclosed in the prior art.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-6, 10-11, 14, and 17-20 of the ’999 patent as unpatentable.