Monday, December 26, 2005

Ranbaxy's arguments about Lipitor fail at D. Delaware

The really "big deal" in the Pfizer v. Ranbaxy case, 2005 U.S. Dist. LEXIS 33393, was an argument by Ranbaxy that Pfizer had not claimed atrovastatin calcium, the active ingredient in Lipitor, in U.S. Patent No. 5,273,995. This hypertechnical argument concerning 35 USC 112 P4 did not get much traction with Judge Joseph J. Farnan Jr., although it did produce some discussion about disagreements among judges of the CAFC about 35 USC 112 P1. Ranbaxy had a weak 112 P1 argument about claims of US 4,681,893, which also went nowhere.

[Note the relevance of the later Energizer, Everyready vs. ITC case, wherein the CAFC rejected a similar hypertechnical argument over 112 P2. Don't bet on Ranbaxy in the appeal.]

On the '893 patent-->

Some text on written description:

the Federal Circuit also acknowledged in Lilly its holding in Utter v. Hiraga, 845 F.2d 993, 998-999 (Fed. Cir. 1988), that "[a]
specification may, within the meaning of ยง 112 P1, contain a written
description of a broadly claimed invention without describing all species that claim encompasses."

In this case, the written description of the '893 patent is a generic formula which the patent specification expressly indicates includes all
trans-enantiomers. Ranbaxy acknowledges that one skilled in the art would know how to resolve racemates into their constituent enantiomers, and therefore, the Court concludes that the generic formula description contained in the '893 patent is sufficient to satisfy the written description requirement, regardless of whether the specific
isomeric compounds are individually described in the patent.

Of the relevance of foreign prosecutions to US litigations:

However, the Federal Circuit has recognized that "'the varying legal and procedural requirements for obtaining patent protection in foreign countries might render consideration of certain types of representations inappropriate' for consideration in a claim construction analysis of a United States counterpart." TI Group Auto. Sys. (N. Am.), Inc. v. VDO N. Am., L.L.C., 375 F.3d 1126, 1136 (Fed. Cir. 2004) (citations omitted).

Of estoppel from a later-prosecuted patent:

In a similar vein, Ranbaxy contends that Pfizer is precluded from
pursuing its proposed claim construction of the '893 patent based on statements made by Warner-Lambert during the prosecution of the '995 patent. However, the Federal Circuit has repeatedly held that arguments from a later, unrelated patent prosecution cannot be used to interpret and/or limit an earlier, unrelated and already issued patent. n3 Integra Lifesciences 1, Ltd. v. Merck KGaA, 331 F.3d 860, 868 (Fed. Cir. 2003), cert. granted on other grounds, 125 S. Ct. 823

On the '995 patent-->

The claim construction issue pertained to claim 6 of the '995 patent.

6. The hemicalcium salt of the compound of claim 2.

The parties' claim construction dispute regarding claim 6 is whether
claim 6 can be construed to cover the salt atorvastatin calcium. Ranbaxy
contends that claim 6 cannot be construed to cover the salt, because claim 6 depends on claim 2 and claim 2 narrows the subject matter of claim 1 from atorvastatin acid or atorvastatin lactone, or harmaceutically acceptable salts thereof to the single
compound, atorvastatin acid.
Ranbaxy argues that because claim 2 does not encompass salts, dependent claim 6 cannot cover the salt atorvastatin calcium. According to Ranbaxy, a reading of claim 6 to include the salt would render the patent invalid under Section 112, paragraph 4.

The Court finds the language of claim 6 to be unambiguous to the
extent that claim 6 is meant to claim the salt, atrovastatin calcium.

Despite this standard use of chemical nomenclature and the fact that
the meaning of claim 6 is clear to those skilled in the art, Ranbaxy
contends that the Court should not interpret claim 6 to refer to atorvastatin calcium, because such an interpretation would render the claim invalid for failure to adhere to the drafting requirements for dependent claims set forth in Section 112. Pursuant to Section 112, paragraph 4, "a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation
of the subject matter claimed."

Darrell L. Olson was on-board for Ranbaxy along with Jay R. Deshmukh, Esquire and George E. Heibel of Ranbaxy.


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