In Re: Entresto -Written Description and Enablement Do Not Have To Be Complicated.
| January 16, 2025
In re: Entresto; Novartis Pharm. Corp. v. Torrent Pharma Inc. et al.
Date of Decision: January 10, 2025
Before: LOURIE, PROST, and REYNA.
Summary:
The Federal Circuit reversed a finding by the District of Delaware that the drug patent covering the heart drug, Entresto was invalid for failing to provide a written description of future embodiments wherein a combination of two drugs where formed in a chemical complex. The Federal Circuit found that the District Court had erred by interpreting the written description requirement as demanding that a future embodiment needed to be adequately described in the patent in order for the claim to be valid. Instead, the CAFC noted that any written description sufficient to describe the claim satisfies the requirement.
Background:
The U.S. District of Delaware determined that claims 1-4 of U.S. Patent 8,101,659 (“the ’659 patent”) owned by Novartis were shown to be invalid for lack of written description. The ‘659 patent covers the heart failure treatment drug, Entresto. Entresto combines two different drug therapies, valsartan and sacubitril, in a specific form known as a “complex,” which combines the two drugs into a single unit-dose-form through weak, non-covalent bonds. During the District Court proceeding there had been a dispute as to the claim construction of the aspect of claim 1 “wherein said [valsartan and sacubitril] are administered in combination.” The District Court gave the term its plain and ordinary meaning as Novartis had argued for.
As a result of this construction, the District Court interpreted the claim to cover valsartan and sacubitril as a physical combination and as a complex (i.e. as used in Entresto). Torrent argued that the ’659 patent was required to enable and describe such complexes, since a patent must enable and describe the full scope of the claims. However, overwhelming evidence (in the form of later patents) showed that the complex of the two drugs was not invented until after the ‘659 patent issued.
As to enablement, the District Court found that because enablement is judged as of the priority date, later-existing state of the art may not be properly considered in the enablement analysis. As to written description, the District found because it was undisputed that complexes were unknown to a person of ordinary skill in the art, “‘[Novartis] scientists, by definition, could not have possession of, and disclose, the subject matter of [such complexes]’ and therefore, ‘axiomatically, [Novartis] cannot satisfy the written description requirement’ for such complexes.”
Novartis appealed. MSN (one of the Torrent defendants) remained for the appeal arguing that either the District Court’s written description determination should be affirmed or the enablement determination reversed.[1]
Discussion:
The CAFC took immediate issue with the manner in which the District Court had interpreted the written description requirement, noting that: “The issue is not whether the ’659 patent describes valsartan-sacubitril complexes. Because the ’659 patent does not claim valsartan-sacubitril complexes, those complexes need not have been described.” (Emphasis in original).
The Court restated the settled law that: “A specification adequately describes an invention when it ‘reasonably conveys to those skilled in the art that the inventor had possession of the claimed subject matter as of the filing date.’” Juno Therapeutics,Inc. v. Kite Pharma, Inc., 10 F.4th 1330, 1335 (Fed. Cir.2021) (quoting Ariad Pharms. Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (en banc)). They then noted that the claim construction had given the term “administered in combination” its plain and ordinary meaning, and that the specification provided ample description of the two drugs being administered together. Therefore, concluding that the claim had adequate written description support and that the District Court had “erroneously conflated the distinct issues of patentability and infringement, which led it astray in evaluating written description.”
Turning to enablement, the CAFC reiterated that the same is true -that it is the claim that must be enabled and not future potential embodiments which are the subject of infringement. Thus, the Circuit Court affirmed the District’s interpretation of enablement.
The district court correctly recognized that valsartan-sacubitril complexes, which include the claimed invention along with additional unclaimed features, are part of a later-existing state of the art” that “may not be properly considered in the enablement analysis.”
Conclusion:
The CAFC concluded that the District Court had erred in finding there was insufficient written description support and reversed and affirmed the District Court’s finding that the claims of the ‘659 patent are enabled.
Take away:
- When reviewing issues of written description and enablement, the review must center on the claim language and the claim construction thereof being supported by the patent.
- Future embodiments of a claim which could not possibly be enabled or described within the patent may still infringe the claim if they read on all the terms thereof as construed. Enablement and written description are issues of patentability not infringement.
[1] Issues of obviousness and indefiniteness were also raised but are not covered herein.
