CHEMICAL PATENT PRACTICE MEETING SUMMARY

AIPLA Spring Meeting 2004

The Chemical Patent Practice Committee held a meeting on Thursday, May 13, 2004, in Dallas, Texas.  About 45 people attended the meeting.

The Committee chair, Susan Wolfe opened the meeting and introduced the featured speakers.  The featured speakers were Mark Skoog, of Merchant & Gould who spoke on the topic of enablement, Steve Szczepanski, of Kelley Drye & Warren who spoke on the topic of anticipation by inherency, Paul Cole, of Lucas & Co. who spoke on empirical research tool inventions and Benjamin Bai of Jones Day, who spoke on the topic of enablement of generic claims.  Mark’s and Steve’s PowerPoint slides are now available on the Committee web page on the AIPLA website.

1.         Skoog Presentation

A summary of the presentation given by Mark Skoog, entitled “Enablement (The Plain Vanilla Variety)” follows.

The first paragraph of 35 U.S.C. § 112 states the enablement requirement.  35 U.S.C. § 112, 1^st paragraph states in relevant part that the patent specification:

. . . shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same” (emphasis added).

The USPTO has provided guidance with respect to the enablement requirement in MPEP § 2164 and other published materials.  Recent cases relating to enablement of inventions in the fields of chemistry and biotechnology were also discussed.

In re Wands sets forth the factors to be considered in making a determination of whether a claim is enabled by the teaching in the specification of an application.  These factors, often referred to as the “Wands Factors”, include:

1. quantity of experimentation necessary;
2. amount of direction or guidance presented;
3. presence or absence of working examples;
4. nature of the invention;
5. state of the prior art;
6. relative skill of the those in the art;
7. predictability or unpredictability of the art; and
8. breadth of the claims.

A recent case of interest dealing with the enablement issue is Chiron Corporation v. Genentech, Inc., No. 03-1158, 1159 (Fed. Cir. March 30, 2004).  The patent at suit related to antibodies against proteins specific to breast cancer cells and claimed priority to applications filed in 1984, 1985 and 1986.  Specifically, there were claims to murine mAb, conjugates, and methods of using them and one claim to a mAb that binds a 210 kD breast cancer protein.  The 1984 application was filed before chimeric Ab was known and the 1986 application was filed before humanized Ab was known.  In the disclosure mAb was defined as “an antibody composition having a homogenous antibody population” and it was stated that it was not intended to be limited in regard to the source of the antibody or the manner of making it.  Several months later, chimeric Ab was invented and humanized Ab became routine several years later.

In 1995 a CIP of the 1980’s applications was filed with broader definitions.  In the 1995 CIP, mAb was defined as “an antibody composition having a homogenous antibody population” and “encompassed whole immunoglobulins”.  Further, it stated that the term antibody “encompasses polyclonal and monoclonal antibody compositions, as well as preparations including chimeric antibodies and humanized antibodies.  The CIP application also disclosed and defined Fab fragments, single chain Ab, humanized Ab, and other advances in antibody technology and molecular biology.  The 210 kD antigen was later determined to be HER2 (MW 185 kD). 

The claims of the 1995 CIP application recited a monoclonal antibody that binds to a human breast cancer antigen that is also bound by monoclonal antibody 454C11 produced by the deposited hybridoma and a monoclonal antibody that binds to human c-erb-2-antigen (aka HER2).   During litigation it was stipulated that the claims of the CIP application were invalid under 35 U.S.C. § 102 if the CIP application was not entitled to priority to the 1980 applications. 

The court reasoned that a patent document cannot enable technology that arises after the date of the application and since chimeric antibody technology arose after the filing date of the 1984 application, it was outside the bounds of the enablement requirement.  The court further stated that chimeric antibodies were a “nascent technology requiring a ‘specific and useful teaching’”.

2.         Szczepanski Presentation

Steve Szczepanski gave a presentation entitled “Anticipation by Inherency” based on the following topical outline.

I.          The Concept of Inherency in Patent Law

II.         Applications of Inherency

A.        Establishing Effective Filing Date under 35 U.S.C. § 120

B.         Establishing Priority Date in an Interference’

C.        Anticipation Under 35 U.S.C. § 102

III.       Inherency in the Context of Anticipation

A.        Specific Definition

B.         The Need for Claim Construction in Defining Inherency

C.        Procedure for Determining Inherency

1. Forward Chronology
2. Backward Chronology

D.        Recognition of an Inherent Feature

E.         Enablement of the Embodiment Containing the Inherent Feature

F.         Inherency to Supply a Missing Limitation

G.        Inherency for the Entire Invention Prior Art Reference

H.        Proof of Inherency

I.          Inherency Distinguished from the Doctrine of Accidental, Unintended and Unappreciated Results

J.          Inherency Distinguished from Obviousness

IV.       Claim Drafting to Avoid Anticipation by Inherency

V.        Conclusion

3.         Cole Presentation

Paul Cole of Lucas & Co., in the United Kingdom gave a presentation entitled “Empirical Research Inventions Allowable Generic Claim Scope”.  A summary of the presentation follows.

This discussion deals with practice in the pharmaceutical industry for claiming new molecular entities and in particular to defining a genus of compounds that validly covers compounds that have not yet been made and tested.

In the early days of the pharmaceutical industry claims were directed to a single molecular entity or compound, such as the Hoffman patent, U.S. Pat. No. 644,077 granted in 1900 for aspirin.

The practice of claiming classes of compounds generically by structural formulae developed in the dyestuffs industry.   U.S. Pat. No. 1,744,172 provides an example of “Markush” practice as it developed in the 1920’s.  The pharmaceutical industry is an offshoot of the dyestuffs industry.

Markush groups were devised for dyestuffs and other relatively simple systems.  The ‘172 patent claimed a class of azo dyes for cotton and it is clearly credible that the whole class of compounds would work for the intended purpose of dying cotton.  However, in the case of pharmaceuticals, the credibility of Markush claims is open to question since human and animal cells are more complex than cotton fibers.

Finding pharmaceutically active compounds has been a task of empirical research similar to that employed by Thomas Alva Edison in developing the incandescent lamp.  In Consolidated Electric Light Co., v. McKeesport Light Co., 159 U.S. 465 (1895),

a case involving infringement by licensees of Edison’s lamp where the patent holder asserted that the patent claims covered all carbonized fibrous or textile materials for use as filaments for electric lamps, the Supreme Court reasoned:

[T]o hold that one who had discovered that a certain fibrous or textile material answered the required purpose should obtain the right to exclude everybody from the whole domain of fibrous and textile materials, and thereby shut out any further efforts to discover a better specimen of that class than the patentee had employed, would be an unwarranted extension of his monopoly, and operate rather to discourage than to promote invention.

This view coincides with the English courts, which follow the basic principle that generic claims are permissible where there is a rational basis for them.  In the case of May & Baker v. Boots, 67 RPC 23 at 50, the House of Lords set out the following principles for research in an empirical art:

(i)         in a field where progress is by empirical discovery, an invention must be in respect of a substance which has actually been produced, since there cannot be an empirical discovery in respect of a bare formula;

(ii)        each new compound is a separate invention since its worth is a new discovery; but

(iii)       where the chemist has found some law or principle by which he can predict therapeutic effect in advance so that each of a group of new products will be of value, the art will have lost its empirical nature, at least to some extent (i.e., Markush claim may be allowable).

In a case in the EPO concerning a class of herbicidal triazole sulphonamides, the dispute was whether the whole class of compounds had to be herbicidal in order to establish patentability or whether it was enough for the applicant to show that some of the compounds were herbicides and the cited art did not teach the skilled person how to make any compound within the class.  Agrevo/Triazoles T 0939/92.  The court held that the selection of such compounds must be justified by an unknown technical effect which is caused by the structural features that distinguish the claimed compounds from numerous other compound and this technical effect must be one that can be fairly assumed to be produced by substantially all of the claimed compounds.

The UK decision in Olin Mathieson v. Biorex, [1970] RPC 157 provides an example where a generic claim was held to be valid.  The court’s decision to uphold the generic claims was primarily based on:

(a) the side chains covered by the patent in issue had been disclosed in earlier patents and had been shown to be active;

(b) there was no reason to expect that a change of the ring substituent from Cl to CF₃ would affect the range of side chains compatible with activity;

(c) for any given side chain the CF₃ substituent at the same position, i.e., the 2-    position gave the highest activity; and

(d) all of the CF₃-substituted compounds that the plaintiffs made and tested were therapeutically active.

Monsanto v. Merck, [2000] RPC 77, is a recently litigated case involving Markush claims that were held to be invalid.  The patent claimed a class of compounds said to exhibit anti-inflammatory an analgesic activity without causing erosion of the lignin of the stomach.  At trial the defendants provided evidence that a number of the compounds covered by the patent did not have the claimed properties and that one of the preferred compounds exhibited all of the undesirable features that the compounds were said to prevent.  The court thus concluded that the patent was invalid and not infringed stating:

If compounds having the features of the claim may or may not possess the qualities which the patent says unify the class, it cannot be said that the claim represents a true class at all.  It is just a generalized description of a large number of chemical compounds.  Such a claim is not analogous to a claim to a new principle, since the patentee has given no information, such as structure/activity relationship, which enables the reader of the specification to draw any conclusions as to the properties of any particular compound without further experiment.  All he has done is to describe the scope of the claim with spurious precision.

In American Home Products, et al v. Novartis, [2000] RPC 547, claimed a new use for rapamycin, a known antifungal antibiotic, as an immunosuppressant.  The claim was written in second medical use format and recited “use of rapamycin for the preparation for a medicament for inhibiting organ or tissue transplant rejection in a mammal in need thereof.”  In the specification, the invention was described as including the use of natural and synthetic rapamycin, genetically engineered rapamycin and all of its derivatives and prodrugs of rapamycin.

At issue during litigation was whether the claim covered the defendants compounds, which was a derivative of rapamycin and if so whether the patent was invalid as lacking a sufficient disclosure for the scope of the claimed compounds.  A third issue was whether there is a distinction between ordinary claims and “second medical use” claims.  The patent was ultimately held to be valid with sufficient disclosure as to the rapamycin compound.  However, the court rejected arguments that the claims covered all rapamycin derivatives and therefore no infringement was found.

In conclusion, overbroad claims should be avoided and participation from chemists, biologists and molecular modelers could be helpful in formulating claims that cover the broadest possible scope that is scientifically supportable based on established structure/activity relationships that can be used as a basis for rational prediction.  Further, it is important to claim the disclosed compounds individually as well as within the genus because the claims to the individual compounds may be the only valid claims.

4.         Bai Presnetation

Benjamin Bai followed Paul Cole with a presentation entitled “Enablement of Generic Claims”.  A summary of the presentation follows.

The question posed is whether an applicant can claim an entire genus when the discovery lies in just a few species, in the absence of prior art. 

The legal standards that we are most concerned with in this context are enablement and written description.  The legal standard for enablement set forth in In re Moore, 429 F.2d 1232, 1236, 169 USPQ 236, 239 (CCPA 1971) is that the scope of enablement must be commensurate with the scope of the claims.  Further, In re Wands, 858 F.2d 731, 737 (Fed. Cir. 1985),sets forth eight factors used to determine whether the claims are enabled.  While no one factor is determinative, two of the eight factors, breadth of the claims and predictability of the art, have special significance in the pharmaceutical art.  There is an inverse relationship between these two factors.  See, e.g., PPG Industries v. Guardian Industries Corp. 75 F.3d 1558 (Fed. Cir. 1996), In re Goodman, 11 F.3d 1046 (Fed. Cir. 1993) and Amgen v. Chugai, 927, F.2d 1200, 1212 (Fed. Cir. 1991).

The “Incandescent Lamp” case, 159 U.S. 465, involving U.S. Patent No. 317,676 discussed by Dr. Paul Cole is an exemplary case, where it was found that description of a species may not support claims to a genus where there is no predictability in the art.  In that case, discovery of the subgenus did not provide sufficient enablement for the genus because there was no quality common to all fibrous and textile materials; most fibrous and textile materials did not work and only certain bamboo strips worked. 

Thus, the scope of enablement varies inversely with the degree of predictability involved.  But, even in unpredictable arts, a disclosure of every operable species is not required.  See,Iin re Vickers, 141 F.2d 522 (CCPA 1944).  For example, in the mechanical and electrical arts, a single embodiment may support a generic claim.

In conclusion:

• Be careful with broad overreaching generic claims
• Describe sub-generic and draft claims of reasonable scope
• Identify common quality giving rise to a particular property
• Predictability is your friend
• Pioneering invention does not necessarily deserve broad claims.

5.         CLE

The Advanced Biotechnology & Chemical Patent Practice Seminar was held June 11 in Seattle, WA, June 18 in St. Louis, MO, and June 25 in Wilmington, DE.  CLE has been requested.  See www.aipla.orgfor additional information.

6.         Judicial and Administrative Decisions

The Judicial Decisions subcommittee provided a written report summarizing recent chemical, biotechnological, and medical device decisions which was included on the CD-ROM distributed to attendees of the Annual Meeting.  A supplemental report was handed out at the meeting.  The report is posted on the Committtee’s web page on the AIPLA web site.  Thanks to Subcommittee Co-Chairs and editors, Steven J. Helmer, Donna Becker, Mark T. Skoog, and Sandra P. Thompson, and the following authors who contributed to the report:

7.         Litigation

Subcommittee Chairpersons, Linda Pingatore and Steve Z. Szczepanski, provided a Litigation Subcommittee Report summarizing several articles dealing with anticipation by inherency.  This report is posted on the Committee’s web page.

Reported by Jennifer M. Hayes