CAFC reminds applicants to be wary of functionally defined genus claims
| July 22, 2014
AbbVie Deutschland GMBH & CO., KG et al., v. Janssen Biotech, Inc.
July 1, 2014
Panel: Lourie, O’Malley, and Chen. Opinion by Lourie. Concurring opinion by O’Malley.
Summary
Functionally defined genus claims can be inherently vulnerable to invalidity challenge for lack of written description, especially in technology fields that are highly unpredictable, where it is difficult to establish a correlation between structure and function for the whole genus or to predict what would be covered by the functionally claimed genus. Functionally defined claims can meet the written description requirement if a reasonable structure-function correlation is established, whether by the inventor as described in the specification or known in the art at the time of the filing date.
Details
Procedural Background
AbbVie owned two patents, U.S. Patent 6,914,128 (the “′128 patent”) and U.S. Patent 7,504,485 (the “′485 patent”), directed to fully human antibodies that bind to and neutralize the activity of human interleukin 12 (“IL-12”). The ′128 and ′485 patents share the same written description of an amino acid sequence of about 300 antibodies having a range of IL-12 binding affinities and structures that are similar but with certain differences.
Centocor filed its ′994 application directed to human IL-12 antibodies (developed under the brand name Stelara® (“Stelara”)), and provoked an interference with the ′128 patent. The Board awarded priority to AbbVie, held that the ′128 patent claims were not invalid for obviousness, and therefore entered judgment in favor of AbbVie.
Following the Board’s decision, AbbVie filed an infringement action against Centocor, asserting that Stelara infringed the ′128 and ′485 patents; and Centocor filed two actions seeking judicial review of the Board’s interference decisions under 35 USC § 146 and seeking a declaratory judgment of noninfringement and invalidity of the ′128 and ′485 patents. Centocor’s two actions were transferred and consolidated with AbbVie’s actions.
After a trial on validity in the infringement action, the jury determined that all of the asserted claims were invalid on the grounds of written description, enablement, and obviousness. The district court denied AbbVie’s post-trial motions for judgment as a matter of law (“JMOL”), and in the alternative, for a new trial, and entered judgments of invalidity in both the infringement and the interference actions.
AbbVie appealed the district court’s decisions in both actions to the CAFC; and the appeals were consolidated. On appeal, AbbVie challenged the district court’s denial of: (1) its motion for summary judgment, in which the district court held that Centocor was not collaterally estopped from raising invalidity defenses in the infringement action after the interference proceeding at the PTO; (2) its motion for JMOL on the issues of written description and enablement; and (3) its motion for a new trial for alleged errors in the court’s evidentiary rulings and jury instructions.
Discussion
This Case Review is limited to the CAFC’s decision on (2), and more specifically, review of the District Court’s decision on the issues of written description and enablement.
There are two techniques used to develop a fully human IL-12 antibody: phage display and transgenic mice. AbbVie used phage display to develop its IL-12 antibodies, including, in order of development, antibodies it named “Joe-9,” “Y61,” and “J695.” These three antibodies had ascending abilities to bind to and neutralize the activity of IL-12. The binding affinity of an antibody to an antigen can be measured by koff, the rate at which the antigen dissociates from the antibody after binding.
The asserted claims of the ′128 and ′485 patents defined the claimed antibodies by their function, i.e., IL-12 binding and neutralizing characteristics, rather than by structure. Claim 29 of the ′128 patent is representative and reads as follows:
29. A neutralizing isolated human antibody, or antigen-binding portion thereof that binds to human IL-12 and disassociates from human IL-12 with a koff rate constant of 1×10 -2 s -1 or less, as determined by surface plasmon resonance.
Centocor developed its human IL-12 neutralizing antibody drug, Stelara, using the transgenic mice technology.
In connection with its invalidity defenses based on lack of written description and enablement, Centocor presented evidence to establish that the J695 and Joe-9 antibodies described in the ′128 and ′485 patents had certain structural characteristics that were identical to each other, but that differed from those of Stelara; so that the antibodies described in AbbVie’s patents were not representative of other members of the functionally claimed genus, which included Stelara. These characteristics are as follows:
In the infringement action, the jury found that each of the asserted claims was invalid for lack of an adequate written description and lack of enablement. AbbVie moved for JMOL as to the invalidity verdict, and in the alternative, for a new trial. The court denied both motions and entered judgment based on the jury verdict in the infringement action.
The CAFC applied the law of the First Circuit, which reviews the denial of a motion for JMOL de novo. JMOL is appropriate when “a reasonable jury would not have a legally sufficient evidentiary basis to find for the party on that issue.” Fed.R.Civ.P. 50(a)(1). Whether a patent claim is supported by an adequate written description is a question of fact, so the CAFC reviewed the jury’s factual determination for substantial evidence.
To satisfy the written description requirement, a patent applicant must describe the invention so that the public will know what it is and that the inventor has truly made the claimed invention; and the specification must show that the inventor has in fact invented what is claimed.
In this case, the claims recited a genus — a class of fully human antibodies defined by their high affinity and neutralizing activity to human IL-12 — but the specification only described part of the genus. Moreover, the claims recited the genus “using functional language to define a desired result.” Was this partial description sufficient to constitute a description of the genus in satisfaction of the written description requirement, given the functional language?
In general, for a description of a genus to be sufficient, it must disclose “either a representative number of species falling within the scope of the genus or structural features common to the members of the genus so that one of skill in the art can ‘visualize or recognize’ the members of the genus.”
In addition, “when a patent claims a genus using functional language to define a desired result, ‘the specification must demonstrate that the applicant has made a generic invention that achieves the claimed result and do so by showing that the applicant has invented species sufficient to support a claim to the functionally-defined genus.’” Whether these hurdles are cleared depends in part on how large a genus is involved and what species of the genus are described in the patent.
Because each of the asserted claims encompassed both the Joe-9 antibodies and the allegedly infringing Stelara, the claimed genus covered structurally diverse antibodies. AbbVie’s expert conceded that the ′128 and ′485 patents did not disclose structural features common to the members of the claimed genus.
The CAFC held that while AbbVie’s patents did not have to describe Stelara in “exact terms,” they at least had to describe some species representative of antibodies that were structurally similar to Stelara. The ′128 and ′485 patents only described species of structurally similar antibodies that were derived from Joe-9. Although the number of the described species appeared “high quantitatively, the described species are all of the similar type and do not qualitatively represent other types of antibodies encompassed by the genus.”
There was no evidence of record to show any described antibody to be structurally similar to, and thus representative of, Stelara; or that one of skill in the art could make predictable changes to the described antibodies to arrive at other types of antibodies such as Stelara.
The CAFC therefore agreed with Centocor that there was substantial evidence to support the jury verdict that the asserted claims were invalid for lack of an adequate written description. The CAFC therefore found it unnecessary to consider the enablement issue.
Take-away
If it is necessary to define a genus claim functionally, rather than structurally, more than usual care should be taken to ensure that there is adequate written description of species that qualitatively represent the types of species encompassed by the genus, especially in technology fields that are highly unpredictable, where it is difficult to establish a correlation between structure and function for the whole genus or to predict what would be covered by the functionally claimed genus.
Where the species are differentiated by their process of manufacture (that is, where, as here, the primary structural differences between species arise due to different manufacturing processes), it may be useful to avoid a genus claim by limit the claim to the species made by a specific process.
