PTAB

IPR2017-00060

Edwards Lifesciences Corp v. Boston Scientific Scimed Inc

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1. Case Identification

2. Patent Overview

  • Title: Prosthetic Heart Valve System
  • Brief Description: The ’608 patent discloses a collapsible and expandable transcatheter heart valve (THV). The system includes an expandable anchor, a replacement valve, and a fabric seal designed to prevent blood from leaking around the prosthesis (paravalvular leak) by forming "flaps" and "pockets" upon deployment.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1-4 under 35 U.S.C. §102(b) over Cribier

  • Prior Art Relied Upon: Cribier (WO 98/29057).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Cribier, which discloses a THV, taught every element of claims 1-4. Specifically, Cribier disclosed an expandable anchor, a replacement valve with commissure supports, and a fabric seal. Petitioner contended that the key limitation requiring the fabric seal to form "flaps" and "pockets" was inherently disclosed. Cribier taught that its anchor frame foreshortens by up to 50% upon expansion. Petitioner asserted that this degree of foreshortening, when applied to a fabric seal secured along the anchor's length, would necessarily cause the fabric to bunch up and form circumferentially oriented folds ("flaps") and resulting open spaces ("pockets"). Furthermore, Petitioner identified Figure 6d of Cribier as disclosing the claimed configuration where the fabric seal extends from the distal end of the valve and rolls back proximally over the external surface of the anchor.

Ground 2: Obviousness of Claims 1-4 under 35 U.S.C. §103(a) over Cribier in view of Elliot or Thornton

  • Prior Art Relied Upon: Cribier (WO 98/29057), Elliot (Application # 2003/0236567), and Thornton (Patent 6,015,431).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that even if Cribier was found not to disclose the "flaps" and "pockets" limitations, these features were well-known sealing structures that would have been obvious to add. Elliot and Thornton both disclosed using fabric "skirts" or flared sealing members on implantable tubular prostheses to prevent endoleaks. These structures were described as having unattached ends that conform to the surrounding tissue and form seals, functioning identically to the claimed "flaps" and "pockets."
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine the teachings of Cribier with either Elliot or Thornton to solve the known problem of paravalvular leakage in THVs. Cribier’s own publications recognized the need for improved sealing. Adding the known external sealing skirts from Elliot or Thornton to Cribier’s THV was presented as a straightforward application of a known solution to a similar device to achieve a predictable result.
    • Expectation of Success: A POSITA would have a high expectation of success, as the components were known to be compatible (e.g., Dacron fabric, nitinol stents) and the sealing principles were well-established in the analogous field of stent grafts.

Ground 3: Obviousness of Claims 1-4 under 35 U.S.C. §103(a) over Spenser in view of Elliot or Thornton

  • Prior Art Relied Upon: Spenser (WO 03/047468), Elliot (Application # 2003/0236567), and Thornton (Patent 6,015,431).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner asserted that Spenser, an alternative primary reference, disclosed a THV system meeting all limitations of claims 1-4 except for the explicit "flaps" and "pockets." Spenser taught an expandable anchor, a valve, commissure supports, and a fabric "cuff portion" that could be rolled over the exterior of the anchor to prevent leakage. As with the Cribier-based grounds, Petitioner argued that Elliot and Thornton supplied the missing "flaps" and "pockets" element.
    • Motivation to Combine: The motivation was identical to the Cribier-based obviousness ground: to improve the sealing function of Spenser's THV by incorporating a known, effective sealing structure from Elliot or Thornton to address the recognized problem of paravalvular leaks.
    • Key Aspects: This ground provided an alternative invalidity theory based on a different foundational THV design, strengthening the overall challenge. Petitioner also argued in an alternative ground (Ground 11) that Spenser alone would anticipate the claims if the Patent Owner's allegedly broad interpretation of "flaps" (i.e., not requiring a circumferential orientation) was adopted.

  • Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Cribier or Spenser with other prior art, including Spiridigliozzi (Application # 2004/0033364), Cook (Application # 2004/0082989), and De Paulis (Patent 6,352,554), all of which were argued to teach various known configurations of fabric seals with pleats, folds, or pockets for preventing leakage in implantable devices.

4. Key Claim Construction Positions

  • Petitioner argued that the terms "flaps" and "pockets" were not terms of art and required construction.
  • "Flaps": Based on the specification and prosecution history, where the examiner equated "flaps" with "pleats," Petitioner proposed that "flaps" should be construed as "circumferentially oriented folds or unattached ends." However, Petitioner also noted that the Patent Owner had argued in a related European proceeding for a broader definition without any directional limitation. Petitioner contended that the prior art disclosed "flaps" under either construction.
  • "Pockets": Based on the specification's description, Petitioner argued that "pockets" are "open spaces or cavities formed by flaps of the fabric seal" which are capable of filling with blood to enhance the seal. This construction was central to showing that references teaching pleated or folded seals inherently disclosed the claimed pockets.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-4 of Patent 8,992,608 as unpatentable.