Edwards Lifesciences LLC v. Colibri Heart Valve LLC

1. Case Identification

• Case #: IPR2022-00611
• Patent #: 10,390,945
• Filed: February 15, 2022
• Petitioner(s): Edwards Lifesciences Corporation and Edwards Lifesciences LLC
• Patent Owner(s): Colibri Heart Valve LLC
• Challenged Claims: 1-10

2. Patent Overview

• Title: Percutaneously Implantable Replacement Heart Valve Device And Method Of Making Same
• Brief Description: The ’945 patent is directed to a transcatheter heart valve device. The device comprises a compressible and expandable stent to which a "dry valve" made of treated mammalian pericardium tissue is directly sutured.

3. Grounds for Unpatentability

Ground 1: Obviousness over Scott in view of Chen - Claims 1-10 are obvious over Scott in view of Chen and the knowledge of a POSITA.

• Prior Art Relied Upon: Scott (Application # 2003/0212454) and Chen (Patent 6,534,004).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Scott taught the core elements of the claimed device, including a compressible and expandable stent, a valve made from treated mammalian pericardium with two to four leaflets, and the valve being directly sutured to the stent. Crucially, Petitioner asserted that Scott’s disclosure of mechanically compressing tissue to reduce its thickness inherently met the limitation of subjecting tissue to "light and mechanical compression to decrease the molecular distance of collagen fibers," as this process squeezes out interstitial water. Scott, however, did not explicitly disclose treating the tissue with glycerol or using gas sterilization. Petitioner argued that Chen supplied these missing elements, disclosing a well-known method of fixing tissue with glutaraldehyde, treating it with glycerol to prevent shrinkage during drying, and terminally sterilizing the final product with sterilizing gas.
  • Motivation to Combine: A POSITA would combine Chen’s tissue treatment method with Scott’s valve design to solve known problems. Chen’s use of glycerol prevents tissue shrinkage during drying and enables the use of gas sterilization, which was known to be advantageous over wet-storage aldehyde solutions. Applying this known treatment to Scott’s compressed tissue would predictably result in a more dimensionally stable, easily storable bioprosthetic valve with a desirable low profile for minimally invasive delivery.
  • Expectation of Success: A POSITA would have had a high expectation of success, as combining the references involved applying a standard, proven tissue treatment process (Chen) to a known valve structure (Scott) to achieve the predictable benefits of improved stability and storability.

Ground 2: Obviousness over Paniagua in view of Chen and Scott - Claims 1-10 are obvious over Paniagua in view of Chen and Scott.

• Prior Art Relied Upon: Paniagua (Application # 2003/0130729), Chen (Patent 6,534,004), and Scott (Application # 2003/0212454).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Paniagua disclosed a percutaneously implantable heart valve with a self-expanding stent and a valve made from bovine pericardium treated with glutaraldehyde. Significantly, Paniagua taught drying the pericardium with a lamp ("artificial light") to make it less slippery and easier to handle before suturing it to the stent. While Paniagua taught using light, it did not teach mechanical compression. Petitioner contended it would have been obvious to incorporate the mechanical compression step taught by Scott, which discloses compressing tissue between two surfaces to reduce thickness and non-uniformity. The additional treatment steps of using glycerol and gas sterilization were supplied by Chen, as in Ground 1.
  • Motivation to Combine: A POSITA would combine these references to improve upon Paniagua's device. A POSITA would be motivated to add Scott's mechanical compression step to Paniagua's process to achieve a thinner, more uniform leaflet, a known objective for improving transcatheter valves. This modification would predictably reduce the valve's insertion profile. Likewise, a POSITA would incorporate Chen's glycerol treatment and gas sterilization for the same reasons as in Ground 1: to improve dimensional stability and enable dry storage.
  • Expectation of Success: The combination represented the application of known techniques (mechanical compression, glycerol treatment) to a known device (Paniagua’s valve) to achieve predictable results (reduced profile, improved stability).

• Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 2) for dependent claims 2, 5, 7, and 10, which added Andersen (Patent 5,411,552) to the Scott and Chen combination to provide further explicit support for using self-expanding stents and stainless steel, which were known design alternatives.

4. Key Claim Construction Positions

• "dry valve": Petitioner proposed that the term "dry" in the context of the "dry valve" should be construed to mean "substantially free from water."
• Relevance: This construction was central to Petitioner's argument that prior art teaching mechanical compression met the claim limitations. Petitioner argued that compressing tissue squeezes out interstitial fluid (primarily water), resulting in a tissue that is "substantially free from water" and therefore "dry" under the proposed construction. The argument was based on the patent’s specification, prosecution history (where the examiner considered freeze-dried tissue art), and the plain meaning of the word.

5. Key Technical Contentions (Beyond Claim Construction)

• Mechanical Compression Reduces Collagen Fiber Distance: Petitioner’s core technical argument was that the physical act of mechanically compressing pericardial tissue, as taught by Scott, inherently achieves the claimed result of "decreas[ing] the molecular distance of collagen fibers." Petitioner explained that uncompressed tissue contains significant void space filled with interstitial fluid. The act of compression expels this fluid, forcing the collagen fibers closer together and thus directly reducing their molecular distance.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial would be inappropriate.
• §314(a) (Fintiv): Petitioner asserted that the Fintiv factors did not favor denial because Petitioner was not a party to any co-pending district court litigation involving the ’945 patent.
• §325(d): Petitioner argued that denial under §325(d) was unwarranted because the primary prior art references relied upon in the petition (Scott, Chen, and Paniagua) were never considered, or even cited, by the examiner during prosecution. Petitioner emphasized that Scott, in particular, expressly disclosed the critical limitation (mechanical compression) upon which the examiner based the allowance of the claims, making the invalidity grounds presented in the petition uniquely strong and not cumulative to the art of record.

7. Relief Requested

• Petitioner requested institution of an inter partes review (IPR) and cancellation of claims 1-10 of Patent 10,390,945 as unpatentable.