United States District Court, W.D. Pennsylvania
November 2, 2005.
PFIZER, INC., Plaintiff and Counterclaim Defendant,
MYLAN LABORATORIES, INC. and MYLAN PHARMACEUTICALS, INC., Defendant and Counterclaim Plaintiffs.
The opinion of the court was delivered by: TERRENCE McVERRY, District Judge
MEMORANDUM OPINION AND ORDER OF COURT
Presently before the Court for disposition is the MOTION FOR
PARTIAL SUMMARY JUDGMENT ON INVALIDITY OF CLAIMS 1-11 OF U.S.
PATENT NO. 4,572,909, with brief in support filed by Defendants
Mylan Laboratories, Inc. and Mylan Pharmaceuticals, Inc.
(collectively referred to as "Mylan") (Document Nos. 78 and
79), the Memorandum in Opposition filed by Pfizer, Inc.
(Document No. 106), and the Reply Brief filed by Mylan (Sealed
Document No. 118). For the reasons that follow, the Motion will
Plaintiff Pfizer, Inc. ("Pfizer") is a pharmaceutical company
whose two patents cover an amlodipine besylate product sold under
the trade name, Norvasc®. The active chemical compound in
Norvasc® is amlodipine, a compound of the class known as
1,4-dihydropyridines. The amlodipine compound in Norvasc® is a
salt, amlodipine besylate.
Amlodipine is protected by United States Patent No. 4,572,909
("the '909 patent"), which covers a genus of compounds, including
a specific claim (claim 8) to amlodipine, pharmaceutical formulations of the claimed compounds, and methods
of treating humans for cardiovascular disease by administering
the claimed compounds. The application for the '909 patent was
filed originally on March 11, 1982, in Great Britain by Pfizer's
British subsidiary. On February 3, 1983, the parent application
for the '909 patent was filed in the United States claiming the
UK filing date of March 11, 1982, as its priority date under
35 U.S.C. § 119. On February 3, 1984, a continuation-in-part
application was filed in the United States, and that application
issued as the '909 patent on February 26, 1986.
The second patented invention utilized in Norvasc® is the
besylate salt of amlodipine, and specific pharmaceutical
formulations of the besylate salt of amlodipine. Amlodipine
besyalte salt is protected by United States Patent No. 4,879,303
("the '303 patent"). A patent application for amlodipine besylate
salt was filed in the UK on April 4, 1986, and filed in the
United States on March 25, 1987. A continuation application was
filed on October 13, 1988, and the patent issued on November 7,
Pursuant to the Patent Term Restoration Act, 35 U.S.C. § 156,
the term of the '909 patent was extended by the Patent and
Trademark Office ("PTO") to July 31, 2006, to restore the time
lost from the patent term while the drug was undergoing FDA
trials and approval. In addition, pursuant to 21 U.S.C. § 355(a),
Pfizer conducted pediatric trials and Norvasc® was awarded six
months "pediatric exclusivity." Thus, the expiration date of the
'909 patent is January 31, 2007. Due to a similar six-month
pediatric exclusivity period, the '303 patent will expire on
September 28, 2007.
On May 22, 2002, Mylan filed an Abbreviated New Drug
Application ("ANDA") in which it sought approval to sell generic
amlodipine besylate. By letter dated July 23, 2002, Mylan certified pursuant to 21 C.F.R. 314.94(a)(12)(i)(A)(4)
(hereinafter referred to as a "paragraph IV certification") that
it was seeking approval to market its generic copy of Norvasc®
prior to the expiration of the '909 and '303 patents. The
application stated that to the best of Mylan's knowledge neither
the '909 nor the '303 patents would be infringed by the
manufacture, use or sale of the proposed generic amlodipine
On September 20, 2002, Pfizer filed this patent infringement
action pursuant to 35 U.S.C. § 271(e), which makes it an act of
infringement to file an ANDA for a drug claimed in a patent.
Mylan's defenses and counterclaims include, inter alia, the
allegation that the '909 patent is invalid based on double
patenting. Specifically, Mylan claims that certain claims of the
'909 patent are invalid for double-patenting over U.S. Patent
4,430,333 (the "'333 patent"), an earlier patent issued to
At issue in the instant motion for partial summary judgment is
the validity of the '909 patent.
STANDARD OF REVIEW
The general standard for summary judgment applies in a patent
case. See Brown v. 3M, 265 F.3d 1349, 1350 (Fed. Cir. 2001)
(general summary judgment standard applies to invalidity).
Accordingly, the burden is on the moving party to establish that
there are no genuine issues of material fact in dispute and that
it is entitled to judgment as a matter of law. See
Fed.R.Civ.P. 56(c); Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 256
(1986). A court must grant summary judgment if the pleadings, depositions,
answers to interrogatories, and admissions on file, together with
affidavits, if any, show that there is no genuine issue as to any
material fact. Celotex Corp v. Catrett, 477 U.S. 317, 325
(1986). A dispute regarding a material fact is genuine "if the
evidence is such that a reasonable jury could return a verdict
for the nonmoving party." Anderson, 477 U.S. at 248.
When a party challenges a patent's validity, the court begins
with the statutory presumption of validity. 35 U.S.C. § 282 ("A
patent shall be presumed valid."). Accordingly, "the burden of
establishing invalidity of a patent or any claim thereof shall
rest on the party asserting such invalidity." Id. Invalidity
must be shown by clear and convincing evidence. Robotic Vision
Sys. v. View Eng'g, Inc., 189 F.3d 1370, 1377 (Fed. Cir. 1999).
This presumption of validity is never weakened, and the burden of
proving invalidity does not shift from the party asserting
invalidity. Imperial Chemical Industries, PLC v. Danbury
Pharmacal, Inc., 745 F. Supp. 998, 1004 (D. Del. 1990) (citing
ACS Hospital Systems, Inc. v. Montefiore Hospital,
732 F.2d 1572, 1574-75 (Fed. Cir. 1984) (other citations omitted)). The
burden of going forward with evidence rebutting invalidity may
shift to the patentee only after the party asserting invalidity
has demonstrated a legally sufficient prima facie case of
invalidity. Ashland Oil, Inc. v. Delta Resins & Refractories,
Inc., 776 F.2d 281, 291 (Fed. Cir. 1985). If the party asserting
invalidity has established a legally sufficient case of
invalidity, the court then examines all of the evidence of
invalidity together with all of the evidence rebutting
invalidity, and determines whether there is clear and convincing
evidence of invalidity. Id. at 291-92.
It is with these principles in mind that the Court turns to the
merits of the motion before it. Discussion
Mylan argues that it is entitled to partial summary judgment
because Claims 1-11 of the '909 patent are "inherently
anticipated by Claims 1-4 and 8-10 of the '333 patent because
practicing the '333 patent claims necessarily and inevitably
produces the metabolites amlodipine and UK-48,265." Mylan Br. at
Pfizer, not surprisingly, strenously argues that the practice
of the claims of the '333 patent does not necessarily result in
the production of a compound claimed by the '909 patent claims,
i.e., namely, amlodopine and UK-48,265. In support of its
argument, Pfizer argues that "one could practice method claim 10
of the '333 patent by using a 1-naphtyle compound and it would
never metabolize to amlodipine." Pfizer Br. at 21-22 (citing
Castagnoli Tr. 156).
The judicially-created doctrine of obviousness-type double
patenting prohibits parties from in effect extending their patent
exclusion rights by filing a later patent with claims that cannot
be considered patentably distinct from claims previously asserted
in a commonly-owned earlier patent. Eli Lilly and Co. v. Barr
Laboratories, Inc., 251 F.3d 955, 967 (Fed. Cir. 2001) (citation
omitted). In reviewing a double patenting claim:
a court construes the claim in the earlier patent and
the claim in the later patent and determines the
differences. Second, the court determines whether the
differences in subject matter between the two claims
render them patentably distinct. A later claim that
is not patentably distinct from an earlier claim in a
commonly owned patent is invalid for obvious-type
double patenting. A later patent claim is not
patentably distinct from an earlier patent claim if
the later claim is obvious over, or anticipated by,
the earlier claim.
Id. at 968 (citations omitted). In assessing obviousness, only
the claims are to be compared, and the Court neither examines
motivation to combine prior art references nor objective standards of non-obviousness as with obviousness inquiries under
35 U.S.C. § 103. Geneva Pharmaceuticals, Inc. v. Glaxosmithkline
PLC, 349 F.3d 1373
, 1378 (Fed. Cir. 2003).
Double patenting, as an invalidity defense, must be proved by
the moving party by clear and convincing evidence, Symbol
Technologies, Inc. v. Opticon, Inc., 935 F.2d 1569, 1580 (Fed.
Cir. 1991) ("a heavy and unshifting burden"), and is considered a
question of law because it relies solely on the terms of what has
been claimed in the two patents at issue, like claim
construction. Georgia-Pacific Corp. v. United States Gypsum
Co., 195 F.3d 1322, 1326 (Fed. Cir. 1999). Thus, the court
cannot rely on the earlier patent's specification as prior art in
evaluating double patenting, though the specification may be used
as in claim construction to evaluate the scope of the claims at
issue. Geneva, 349 F.3d at 1385.
The first step in the analysis of the validity issues raised by
the instant motion for partial summary judgment is claim
construction, that is, the determination of the ordinary and
customary meaning that would be attributed to the claim terms by
those skilled in the art. Markman v. Westview Instruments,
Inc., 52 F.3d 967, 979 (Fed. Cir. 1995) (en banc), aff'd,
517 U.S. 370 (1996). The construction of the relevant claims of the
'909 and '333 patents appears to be undisputed.*fn5 Thus, in
construing the relevant claims, the Court will rely upon the
plain language of the claims and, where the language is unclear,
The next step in the analysis is for the Court to determine
whether the differences in subject matter between the claims
render the claims patentably distinct. Georgia-Pacific Corp. v.
United States Gypsum Co., 195 F.3d 1322, 1327 (Fed. Cir. 1999),
cert. denied, 531 U.S. 816 (2000). A later claim that is not patently distinct from an
earlier claim in a commonly owned patent is invalid for
nonstatutory double patenting. In re Berg, 140 F.3d 1428, 1431
(Fed. Cir. 1998). "A later patent claim is not patentably
distinct from an earlier patent claim if the later claim is
obvious over, or anticipated by, the earlier claim." Eli Lilly &
Co. v. Barr Labs, Inc., 251 F.3d 955, 968 (Fed. Cir. 2001).
"A reference is anticipatory if it discloses every limitation
of the claimed invention either explicitly or inherently. . . . A
reference includes an inherent characteristic if that
characteristic is the `natural result' flowing from the
reference's explicitly explicated limitations." Id. at 970. If
the later claim is anticipated by the earlier claim, there can be
no patentable distinction, as a matter of law. Id. In order to
receive patent protection the newly claimed invention must be
novel and distinct from all previously claimed patented
inventions the holder owns. Id.
As stated supra, Mylan argues that "the undisputed evidence
shows the production of metabolites UK-46,265 and amlodipine upon
administration of UK-46,129 ['333]. . . . Thus, the natural
metabolic production of the claimed metabolites, here amlodipine
and UK-48,265, flow from practicing claims directed to a parent
compound, here UK-46,129." Mylan Br. at 11.
In support of its position, Mylan relies, inter alia, on
Schering Corp. v. Geneva Pharmaceuticals, 339 F.3d 1373 (Fed.
Cir. 2003), in which the Federal Circuit Court held that "the
metabolite of the prior art [patent] is the same compound as the
claimed invention." In Schering, it was undisputed that after
clinical trials involving 864 humans and 21 clinical studies, no
human had been found that did not metabolize the [prior art
compound] to the [same compound as the claimed invention.]" Thus, the parties agreed
that the claims at issue covered a metabolite of the prior art
In rebuttal, Pfizer argues, that "the facts show that the
practice of claims of the '333 patent does not necessarily
result in the production of a compound claimed by the '909
patent claims." Pfizer Br. at 20 (emphasis in original). In the
alternative, Pfizer argues that "even assuming arguendo that
the use of UK-46,129 claimed in the '333 patent in animals would
always and necessarily result in the production of UK-48,265 and
amlodipine because of their formation of metabolites, amlodipine
and UK-48,265 are indisputably not claimed in the '333 patent."
Id. at 19 (emphasis in original).
Further, Pfizer argues that the '333 patent describes a genus
of 1,4-dihydropyridine compounds that are either secondary or
primary amines not tertiary amines as in the '333 patent. All
of the compounds in the '333 patent have a tertiary amine
substituent at the 2-position of the molecule.
Unlike the parties in the Schering case, the parties in the
present case do not agree that the practice of claims of the '333
patent necessarily result in the production of a compound claimed
by the '909 patent claims.
Therefore, based on the record upon which summary judgment is
to be determined, the Court finds and rules that Mylan has not
come forward with clear and convincing evidence that claims 1-11
of the '909 patent were anticipated by the '333 patent.
Specifically, there are genuine issues of material fact, due to
competing expert opinions, as to what is disclosed and claimed by
the '333 patent. Therefore, summary judgment as to whether claims
1-11 of the '909 patent are anticipated by the '333 patent is not
appropriate at this time. CONCLUSION
For the reasons stated above, the Motion for Partial Summary
Judgment on Invalidity of Claims 1-11 of U.S. Patent No.
4,572,909 filed by Defendants Mylan Laboratories, Inc. and Mylan
Pharmaceuticals, Inc. will be denied.
An appropriate Order follows. ORDER OF COURT
AND NOW, this 2nd day of November, 2005, in accordance with the
foregoing Memorandum Opinion, it is hereby ORDERED, ADJUDGED,
AND DECREED that the Motion for Partial Summary Judgment on
Invalidity of Claims 1-11 of U.S. Patent No. 4,572,909 filed by
Defendants Mylan Laboratories, Inc. and Mylan Pharmaceuticals,
Inc. is DENIED.
© 1992-2005 VersusLaw Inc.