United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued December 6, 2004 Decided December 21, 2004
No. 04-5211
APOTEX , INC.,
APPELLANT
v.
FOOD & DRUG ADMINISTRATION, ET AL.,
APPELLEES
Appeal from the United States District Court
for the District of Columbia
(No. 04cv00605)
William A. Rakoczy argued the cause for appellant. With
him on the briefs were Christine J. Siwik, Matthew O. Brady,
Amy D. Brody, Lara Monroe-Sampson, and Arthur Y. Tsien.
Charles J. Raubicheck argued the cause for appellee
Purepac Pharmaceutical Company. With him on the brief was
William B. Schultz. Ronald H. Weich entered an appearance.
Howard S. Scher, Attorney, U.S. Department of Justice,
argued the cause for federal appellees. With him on the brief
were Peter D. Keisler, Assistant Attorney General, Kenneth L.
Wainstein, U.S. Attorney, Douglas N. Letter, Attorney, Alex M.
Azar, II, General Counsel, U.S. Department of Health & Human
2
Services, Daniel E. Troy, Chief Counsel, and Karen E. Schifter,
Counsel.
Before: EDWARDS, SENTELLE, and RANDOLPH, Circuit
Judges.
Opinion for the Court filed by Circuit Judge EDWARDS.
EDWARDS, Circuit Judge: Since December 2002, the
District Court has issued three decisions in connection with
disputes between Apotex, Inc. ("Apotex") and Purepac
Pharmaceutical Co. ("Purepac") over the marketing of a generic
version of the drug gabapentin. The Food and Drug
Administration ("FDA" or "agency") has approved gabapentin,
sold by Pfizer, Inc. ("Pfizer") under the brand name Neurontin,
for the treatment of epilepsy. The first two decisions, Purepac
Pharmaceutical Co. v. Thompson, 238 F. Supp. 2d 191 (D.D.C.
2002) ("Purepac I"), and TorPharm, Inc. v. Thompson, 260 F.
Supp. 2d 69 (D.D.C. 2003) ("TorPharm"), were affirmed by this
court in a consolidated appeal. See Purepac Pharm. Co. v.
Thompson, 354 F.3d 877 (D.C. Cir. 2004) ("Purepac II").
At issue in this case is a dispute over the proper
interpretation and application of the pre-amended version of the
180-day generic marketing exclusivity provision of the Federal
Food, Drug, and Cosmetic Act ("FDCA"), 21 U.S.C. §
355(j)(5)(B)(iv) (2000) (amended 2003). The parties disagree
over whether the pre-2003 version of this statutory provision
adopts a "patent-based" approach or "first-filer" approach in
establishing the 180-day period for generic marketing
exclusivity. Applying a patent-based interpretation of §
355(j)(5)(B)(iv), FDA awarded Purepac two separate periods of
180-day exclusivity for the same generic gabapentin drug.
Purepac's first exclusivity period has expired. But the second
exclusivity period, which FDA awarded on the basis of a later-
listed patent, is now running and will not expire until April
2005. Meanwhile, FDA has delayed final approval of Apotex's
3
application to market its generic version of gabapentin pending
the expiration of Purepac's period of marketing exclusivity.
Apotex claims that FDA erred in awarding multiple 180-day
periods of marketing exclusivity for the same drug when, in its
view, the statute allows only awards for a single period of
exclusivity to the first applicant.
Apotex filed the present suit in District Court against FDA
and federal officials (collectively "federal appellees"),
advancing Apotex's interpretation of § 355(j)(5)(B)(iv) and
seeking an injunction directing FDA to issue final approval for
Apotex's gabapentin application. Purepac intervened as a
defendant. After consolidating Apotex's motion for a
preliminary injunction and defendants' motions to dismiss or for
summary judgment, the District Court granted summary
judgment to defendants. The District Court's judgment rested on
two grounds. First, the District Court ruled that res judicata
barred Apotex's action, because the parties in this case are the
same parties who appeared in TorPharm; a final judgment was
rendered against Apotex in TorPharm; the causes of action in
this case and TorPharm share a common nucleus of facts; there
has been no intervening change in the law; and there have been
no material changes in the facts since the judgment in
TorPharm. In the alternative, the District Court held that, even
if res judicata did not apply, the defendants would be entitled to
summary judgment, because FDA's interpretation of §
355(j)(5)(B)(iv) was reasonable and thus entitled to deference.
We agree that res judicata bars Apotex from bringing this
suit. Therefore, we affirm the judgment of the District Court on
this ground alone. We vacate the District Court's alternative
holding reaching the merits of whether FDA's interpretation of
21 U.S.C. § 355(j)(5)(B)(iv) is reasonable.
4
I. BACKGROUND
A. Statutory and Regulatory Framework
The FDCA requires that companies seeking to market a
drug that has not previously been approved by FDA submit a
New Drug Application ("NDA") to FDA. See 21 U.S.C. §
355(b)(1) (2000), amended by Pediatric Research Equity Act of
2003, Pub. L. No. 108-155, § 2(b), 117 Stat. 1936, 1941 (2003).
NDAs are usually lengthy, and they must include, among other
things, evidence surrounding the drug's safety and information
about any patents that cover or might cover the drug. Purepac
Pharm. Co. v. Thompson, 354 F.3d 877, 879 (D.C. Cir. 2004)
("Purepac II") (citing 21 U.S.C. § 355(b)(1)).
In 1984, Congress passed the Hatch-Waxman Amendments
to the FDCA. See Drug Price Competition and Patent Term
Restoration Act of 1984, Pub. L. No. 98-417, 98 Stat. 1585
(1984) ("Hatch-Waxman"). Hatch-Waxman eased the process
of generic drug approval by allowing companies seeking to
market generic versions of approved drugs to submit
Abbreviated New Drug Applications ("ANDAs"). ANDAs must
contain, among other things, information demonstrating that the
generic version is the bioequivalent of the approved version of
the drug. See 21 U.S.C. § 355(j)(2)(A)(iv) (2000).
ANDAs must also address patents that apply or might apply
to the drug for which the ANDA is submitted. ANDA
applicants can satisfy this requirement by making one of four
certifications with regard to the patent's claim on the drug. Id.
§ 355(j)(2)(A)(vii). The relevant certification for the purposes
of this case, known as a "paragraph IV certification," requires
an ANDA applicant to certify that "such patent is invalid or will
not be infringed by the manufacture, use, or sale of the new drug
for which the application is submitted." Id. §
355(j)(2)(A)(vii)(IV). When an ANDA includes a paragraph IV
certification, the ANDA applicant must notify the owner of the
5
patent and the holder of the NDA for the approved drug. See id.
§ 355(j)(2)(B)(i). If a patent infringement lawsuit is brought
against the ANDA applicant within 45 days from the date notice
is received, FDA's approval of the ANDA is automatically
stayed for 30 months. See id. § 355(j)(5)(B)(iii).
An ANDA applicant who submits a paragraph IV
certification is entitled under certain circumstances to a 180-day
period of generic marketing exclusivity during which no other
company can market a generic version of the drug. See id. §
355(j)(5)(B)(iv). This exclusivity provision was amended in
2003, but this case arose under § 355(j)(5)(B)(iv) as it existed
prior to the 2003 Amendments. See Medicare Prescription
Drug, Improvement, and Modernization Act of 2003, Pub. L.
No. 108-173, § 1102, 117 Stat. 2066, 2457-60 (2003) ("2003
Amendments"). All references to § 355(j)(5)(B)(iv) are to the
statute as it existed prior to the 2003 Amendments.
Because we conclude that Apotex is barred by res judicata
from bringing this case, we need not provide an elaborate
discussion of this generic marketing exclusivity provision.
Rather, what is important here is that the parties have advanced
competing interpretations of § 355(j)(5)(B)(iv). These
competing interpretations emanate from the fact that NDA
holders may receive additional patents that claim an approved
drug, or that claim a method of use for the drug, after the
approval of their NDAs. Thus, an ANDA applicant who filed
the first ANDA with a paragraph IV certification for a particular
drug may not be the first ANDA applicant to file paragraph IV
certifications for all patents that claim the drug.
Consistent with FDA's determination in this case, the
federal appellees and Purepac understand § 355(j)(5)(B)(iv) to
allow a company to be eligible for a period of generic marketing
exclusivity if it was the first ANDA applicant to file a paragraph
IV certification for a particular patent, once the other statutory
triggers are satisfied, even if another company had previously
6
filed a paragraph IV certification for another patent claiming the
same drug. Under this interpretation, multiple companies could
be eligible for generic marketing exclusivity, and multiple
periods of exclusivity are possible. This is the so-called "patent-
based approach." By contrast, Apotex argues that §
355(j)(5)(B)(iv) should be interpreted to grant generic marketing
exclusivity only once – i.e., only to the generic manufacturer
who filed the first ANDA with a paragraph IV certification for
any patent involving a particular drug product, and only based
on that first paragraph IV certification. This is the "first-filer
approach."
Although no court had addressed these competing
interpretations before January 2004, the possible tension
between them has been apparent since at least 1999. In August
of that year, FDA issued a proposed rule that would have
adopted the first-filer approach. See 180-Day Generic Drug
Exclusivity for Abbreviated New Drug Applications, 64 Fed.
Reg. 42,873, 42,875 (Aug. 6, 1999) ("August 1999 proposed
rule"). The agency never implemented the August 1999
proposed rule, however, and instead continued to apply the
patent-based approach in disputes surrounding generic
marketing exclusivity. See, e.g., Letter from FDA's Office of
Generic Drugs ("OGD") to Genpharm, Inc. of 11/16/01, Joint
Appendix ("J.A.") 1124, 1128-30; Letter from OGD to
American Pharmaceutical Partners, Inc. of 2/4/03, J.A. 1149,
1152-54. The August 1999 proposed rule was formally
withdrawn in 2002. See 180-Day Generic Drug Exclusivity for
Abbreviated New Drug Applications, 67 Fed. Reg. 66,593 (Nov.
1, 2002).
Before turning to the factual background of the present
dispute, we note that the four types of certifications enumerated
in 21 U.S.C. § 355(j)(2)(A)(vii) are not the only mechanisms by
which an ANDA applicant can address a potentially relevant
patent. A generic company can instead submit a statement
7
pursuant to 21 U.S.C. § 355(j)(2)(A)(viii) ("section viii
statement"). A section viii statement asserts that a patent does
not prevent FDA from approving the company's ANDA because
the ANDA applicant seeks to market the drug for a use other
than that covered by the patent. See 21 U.S.C. §
355(j)(2)(A)(viii). As we have previously explained, applicants
use paragraph IV certifications to challenge the validity of
applicable patents, whereas they submit section viii statements
to assert that patents do not apply. Purepac II, 354 F.3d at 880.
ANDA applicants who submit section viii statements are not
eligible for generic marketing exclusivity pursuant to 21 U.S.C.
§ 355(j)(5)(B)(iv).
B. Facts
As noted above, this case involves gabapentin, a drug sold
by Pfizer under the name Neurontin, which FDA has approved
for the treatment of epilepsy. In 1993, FDA approved Neurontin
capsules based on a NDA submitted by Warner-Lambert Co.
("Warner-Lambert"), which later assigned Pfizer the rights to
Neurontin. In 1997, Warner-Lambert submitted information to
FDA on two patents that were not part of its original NDA
filing: U.S. Patent Nos. 4,894,476 ("'476 patent"), claiming a
crystal form of gabapentin, and 5,084,479 ("'479 patent"),
claiming a method for using gabapentin to treat
neurodegenerative diseases. See Letter from Parke-Davis to
FDA of 7/1/97, J.A. 445, 448. In 2000, Warner-Lambert
submitted information on an additional patent, U.S. Patent No.
6,054,482 ("'482 patent"), claiming a pharmaceutical
composition of gabapentin. See Submission from Warner-
Lambert to FDA of 4/25/00, J.A. 452, 453.
In 1998, Purepac submitted ANDAs for a generic version
of gabapentin. Purepac's ANDAs contained a paragraph IV
certification for the '476 patent and a section viii statement for
the '479 patent. In May 2000, Purepac submitted a paragraph IV
certification to FDA with respect to the '482 patent. Purepac
8
was the first ANDA applicant to file paragraph IV certifications
for the '476 and '482 patents. See Purepac Pharm. Co. v.
Thompson, 238 F. Supp. 2d 191, 198-200 (D.D.C. 2002)
("Purepac I").
Apotex also submitted an ANDA for gabapentin in 1998,
and Apotex ultimately submitted paragraph IV certifications for
all three patents, as well as a section viii statement for the '479
patent. Id. at 200. (Apotex was at that time an affiliate of
TorPharm Corp.; the distinction between Apotex and TorPharm
Corp. is of no relevance for this appeal, and we refer to the
companies both individually and collectively as "Apotex.")
In two separate proceedings filed in 1998, Warner-Lambert
sued Purepac and Apotex for infringement of the '476 and '479
patents. Although Warner-Lambert ultimately lost both suits,
the ANDAs filed by Purepac and Apotex were stayed for 30
months pursuant to 21 U.S.C. § 355(j)(5)(B)(iii). See Purepac
I, 238 F. Supp. 2d at 200-01 & n.14. In 2000, Warner-Lambert
initiated lawsuits against both Purepac and Apotex for
infringement of the '482 patent. Under FDA's then-prevailing
interpretation of the statute, these lawsuits triggered additional
30-month stays before FDA could approve the companies'
ANDAs. See id. at 201 & n.15. Purepac's 180-day exclusivity
period based on the paragraph IV certification for the '476 patent
began in 2001, when all statutory conditions were satisfied.
However, Warner-Lambert's '482 infringement suit precluded
FDA from granting final approval of Purepac's ANDA, so
Purepac's exclusivity period passed without Purepac having the
opportunity to market the drug.
In April 2002, FDA notified Purepac that, because, in the
agency's view, a section viii statement was not appropriate for
the '479 patent, Purepac could not receive final approval of its
ANDA before it filed a certification for the '479 patent. See id.
at 199. Purepac filed suit in District Court challenging FDA's
decision. Purepac also sought to enjoin FDA from approving
9
Apotex's ANDA for gabapentin, because of the adverse
consequences of such approval for any exclusivity Purepac
would have pursuant to its paragraph IV certification for the '482
patent. See id. at 211 & n.27. Apotex intervened as a defendant,
arguing among other things that Purepac's claims were barred by
the doctrine of laches. See id. at 201. Apotex did not present
the first-filer interpretation of § 355(j)(5)(B)(iv). Because
Purepac's paragraph IV certification for the '476 patent was the
first paragraph IV certification submitted for any patent
claiming gabapentin, the first-filer approach would not have
promoted generic marketing exclusivity for the ANDAs relating
to the '479 an '482 patents. Rather, an argument founded on the
first-filer approach would have rested on the premise that no
ANDA, save for the one related to the '476 patent, could serve
as the basis for generic marketing exclusivity to the
disadvantage of competing claims. Apotex did not raise this
argument in the Purepac I litigation.
The District Court ruled in Purepac's favor on the section
viii issue, ordering FDA to accept Purepac's section viii
statement. See Purepac I, 238 F. Supp. 2d at 193. However, the
court declined to enjoin FDA from approving Apotex's ANDA,
stating that it was up to FDA to determine, in the first instance,
the effect of the court's decision. See id. at 211-12.
In response to Purepac I, FDA sought comments from
generic gabapentin applicants, including Apotex and Purepac.
See Letter from OGD to Apotex of 12/18/02, J.A. 741; Letter
from OGD to Purepac of 12/18/02, J.A. 896. Apotex submitted
several letters, which argued that, notwithstanding Purepac I,
Apotex was entitled to at least share in any exclusivity period
with Purepac, because Apotex was the first to file a paragraph
IV certification for the '479 patent. In addition, the letters
asserted that Apotex was the first company to submit a valid
paragraph IV certification for the '482 patent. Once again,
Apotex did not raise the first-filer approach to §
10
355(j)(5)(B)(iv). See, e.g., Letter from Gilbert's to OGC of
1/7/03, J.A. 984; Letter from Gilbert's to OGC of 1/9/03, J.A.
1031.
On January 28, 2003, FDA issued a letter ruling addressing
the dispute between Purepac and Apotex concerning generic
marketing exclusivity for gabapentin. FDA sided with Purepac,
ruling that Apotex was not entitled to any exclusivity based on
its paragraph IV certification for the '479 patent, and that
Purepac alone would be entitled to exclusivity based on the '482
patent. Letter from OGD to Apotex and Purepac of 1/28/03,
J.A. 743, 744, 747-50.
Apotex challenged FDA's actions in District Court. Once
again, Apotex failed to advance the first-filer interpretation of 21
U.S.C. § 355(j)(5)(B)(iv). Rather, Apotex argued for a patent-
based interpretation of the statute, contending that Apotex was
entitled to exclusivity based on its paragraph IV certification for
the '482 patent, or that Apotex should at least be eligible for a
period of shared exclusivity along with Purepac based on
Apotex's submission of the first paragraph IV certification for
the '479 patent. See Letter from OGD to TorPharm of 2/6/04,
J.A. 802, 803 (quoting TorPharm's Memorandum in Support of
its Motion for Preliminary Injunction (Feb. 14, 2003)). In April
2003, the District Court rejected Apotex's challenge, entering
summary judgment in favor of FDA. TorPharm, Inc. v.
Thompson, 260 F. Supp. 2d 69, 71 (D.D.C. 2003) ("TorPharm").
Apotex appealed the District Court's decisions in both
Purepac I and TorPharm. Once again, Apotex failed to advance
the first-filer interpretation of 21 U.S.C. § 355(j)(5)(B)(iv). This
court consolidated the appeals and affirmed the District Court's
rulings in all respects on January 20, 2004. Purepac II, 354 F.3d
at 878-79.
Less than two weeks before this court's decision in Purepac
II, District Court Judge Roberts issued a written order
11
memorializing an oral decision in a separate action filed by
Apotex regarding generic marketing exclusivity for the drug
paroxetine. TorPharm, Inc. v. FDA, No. Civ. A. 03-2401, 2004
WL 64064 (D.D.C. Jan. 8, 2004) ("Paroxetine"), vacated as
moot, No. 04-5046 (D.C. Cir. Dec. 17, 2004). In Paroxetine,
Judge Roberts ruled that the plain language of 21 U.S.C. §
355(j)(5)(B)(iv) compelled the first-filer as opposed to the
patent-based interpretation of the statute. See id. Based on
Paroxetine, Apotex submitted a letter to FDA requesting
immediate approval of its gabapentin ANDA. For the first time,
Apotex asserted that FDA was bound to follow the first-filer
approach in awarding generic marketing exclusivity for
gabapentin. As explained above, under the first-filer approach,
Purepac's exclusivity for gabapentin stemmed solely from the
'476 patent, and that exclusivity period had expired. See Letter
from TorPharm to OGD of 1/15/04, J.A. 761, 762.
On February 6, 2004, FDA rejected Apotex's request. The
agency concluded that Apotex had waived the argument as the
company had not previously raised it before FDA, the District
Court, or this court, despite having had the opportunity to do so
in the previous litigation concerning gabapentin. In fact, FDA
noted that Apotex had taken the opposite position – making
exclusivity arguments premised on the patent-based reading of
the statute. According to FDA, the doctrine of judicial estoppel
barred Apotex from advancing these inconsistent positions. See
Letter from OGD to TorPharm of 2/6/04, J.A. 802, 802-04. The
agency also rejected Apotex's contention that collateral estoppel
required that FDA adopt the first-filer approach in line with
Paroxetine, and announced that it would continue to apply the
patent-based approach in determining exclusivity for gabapentin
ANDAs. See id., J.A. 804.
Apotex challenged FDA's decision in District Court, and
Purepac intervened as a defendant. Speaking through Judge
Huvelle, the District Court ruled for the agency. Apotex, Inc. v.
12
FDA, No. Civ. A. 04-605 (D.D.C. June 3, 2004) (oral decision),
reprinted in J.A. 8-34. The court held that Apotex's claims were
barred by res judicata, and that collateral estoppel did not
prevent FDA from implementing the patent-based approach to
§ 355(j)(5)(B)(iv) concerning gabapentin ANDAs. See id., J.A.
32. Judge Huvelle also went on to consider the merits of the
statutory interpretation question. Recognizing that she was not
bound by Judge Roberts' Paroxetine decision, Judge Huvelle
concluded that FDA's patent-based interpretation of 21 U.S.C.
§ 355(j)(5)(B)(iv) was reasonable, and that the court would defer
to it. See id., J.A. 32-34. Apotex filed the present appeal.
II. ANALYSIS
A. Standard of Review
We review the District Court's grant of summary judgment
de novo. Cruz v. Am. Airlines, Inc., 356 F.3d 320, 328 (D.C.
Cir. 2004). Because the material facts of this case are not in
dispute, "our task is to ensure that the District Court correctly
applied the relevant law to the undisputed facts." Beckett v. Air
Line Pilots Ass'n, 995 F.2d 280, 284 (D.C. Cir. 1993).
B. Res Judicata
Also known as claim preclusion, the doctrine of res judicata
holds that a judgment on the merits in a prior suit bars a second
suit involving identical parties or their privies based on the same
cause of action. Drake v. FAA, 291 F.3d 59, 66 (D.C. Cir.
2002). Res judicata plays a central role in advancing the
"purpose for which civil courts have been established, the
conclusive resolution of disputes within their jurisdictions."
Montana v. United States, 440 U.S. 147, 153 (1979). As the
Supreme Court has explained: "To preclude parties from
contesting matters that they have had a full and fair opportunity
to litigate protects their adversaries from the expense and
vexation attending multiple lawsuits, conserves judicial
13
resources, and fosters reliance on judicial action by minimizing
the possibility of inconsistent decisions." Id. at 153-54.
In this case, Apotex does not dispute that TorPharm was a
judgment on the merits by a court of competent jurisdiction
involving the identical parties. Rather, Apotex argues res
judicata does not bar its suit because the cause of action here is
not identical to the cause of action in TorPharm. Apotex's
argument is unpersuasive.
"Whether two cases implicate the same cause of action
turns on whether they share the same 'nucleus of facts.'" Drake,
291 F.3d at 66 (quoting Page v. United States, 729 F.2d 818,
820 (D.C. Cir. 1984)). In pursuing this inquiry, the court will
consider "'whether the facts are related in time, space, origin, or
motivation, whether they form a convenient trial unit, and
whether their treatment as a unit conforms to the parties'
expectations or business understanding or usage.'" I.A.M. Nat'l
Pension Fund v. Indus. Gear Mfg. Co., 723 F.2d 944, 949 n.5
(D.C. Cir. 1983) (quoting 1B J. MOORE, MOORE'S FEDERAL
PRACTICE ¶ 0.410[1] (2d ed. 1983)).
Apotex maintains that the facts of this case are not related
in time, space, origin, or motivation to those of TorPharm and
that they would not form a convenient trial unit. But TorPharm
and the case at bar each involve a dispute between Apotex and
Purepac over generic marketing exclusivity and final ANDA
approval for the drug gabapentin. Moreover, the relevant
patents – and the companies' submissions relating to those
patents – have not changed since Apotex filed suit in TorPharm .
Thus, the underlying facts of the two cases are closely related in
time, space, origin, and motivation, and they would have formed
a convenient trial unit.
Apotex nonetheless insists that this case involves
submissions relating to the '476 patent, whereas TorPharm
involved submissions surrounding the '482 and '479 patents.
14
Apotex Br. at 53-55. This is not an accurate description of the
two cases. Apotex chose not to present the first-filer
interpretation of 21 U.S.C. § 355(j)(5)(B)(iv) before the court in
TorPharm. Apotex's argument in this case is that, following the
first-filer approach, FDA has no authority under §
355(j)(5)(B)(iv) to award multiple 180-day periods of generic
marketing exclusivity for the same drug. Apotex could have
presented the same argument to challenge FDA's decision in
TorPharm. Apotex chose not to do so. There are no new facts.
Apotex is simply raising a new legal theory. This is precisely
what is barred by res judicata. See Drak e, 291 F.3d at 66
("[U]nder res judicata, 'a final judgment on the merits of an
action precludes the parties or their privies from relitigating
issues that were or could have been raised in that action.'")
(quoting Allen v. McCurry, 449 U.S. 90, 94 (1980)) (emphasis
in original).
Apotex also argues that res judicata does not apply here,
because Judge Roberts' decision in Paroxetine effected a
significant change in circumstances after TorPharm had issued.
Res judicata does not bar parties from bringing claims based on
material facts that were not in existence when they brought the
original suit. Drake, 291 F.3d at 66. And, in a small set of
cases, a change in controlling legal principles may allow a party
to relitigate a claim that would otherwise be barred by res
judicata. See Hardison v. Alexander, 655 F.2d 1281, 1288-89
(D.C. Cir. 1981) (stating that in general res judicata applies
even if there has been a subsequent change in the law of the
circuit, but noting that there are exceptions for reasons of
compelling public policy, such as cases involving important
questions of constitutional law). Neither exception applies here.
It is true that Judge Roberts' opinion in Paroxetine
embraced the legal theory that Apotex is advancing in this case,
but this was not a "change" either in the facts or the law
sufficient to overcome the effects of res judicata. The relevant
15
facts here involve the effect of paragraph IV certifications
submitted by Purepac and TorPharm for the '476 and '482
patents. These certifications were submitted well before Apotex
brought suit in TorPharm. Moreover, Judge Roberts' decision
in Paroxetine is not a change in controlling legal principles.
Judge Huvelle was not bound by Judge Roberts' decision, from
which an appeal was pending, and neither Judge Roberts' nor
Judge Huvelle's decision established the law of the circuit. See
In re Executive Office of the President, 215 F.3d 20, 24 (D.C.
Cir. 2000) ("District Court decisions do not establish the law of
the circuit, nor, indeed, do they even establish the law of the
district.") (citations and internal quotations omitted).
Apotex presents two additional arguments as to why res
judicata should not apply in this case, neither of which have
merit. First, Apotex argues that it would have been
impracticable for Apotex to have presented the first-filer
interpretation of 21 U.S.C. § 355(j)(5)(B)(iv) in TorPharm,
because the company elected to argue that it was entitled to
generic marketing exclusivity for gabapentin under the patent-
based approach to the statute. This argument fails. It is true that
res judicata does not prevent parties from later bringing claims
that "would have been utterly impracticable to join" in an earlier
suit. United States Indus., Inc. v. Blake Constr. Co., 765 F.2d
195, 205 n.21 (D.C. Cir. 1985). But it would not have been
"utterly impractical" for Apotex to raise the first-filer argument
to advance its cause in TorPharm. Indeed, at oral argument,
Apotex's counsel did not deny that Apotex could have presented
the first-filer approach as an alternative argument in TorPharm.
Recording of Oral Argument at 7:52-:59. Rather than seeking
the advantage that flows from having alternative arguments,
either of which in Apotex's view would have supported its claim
in TorPharm, Apotex chose instead to argue solely in favor of
the patent- based approach, which is diametrically opposed to the
first-filer theory that Apotex advances in this case.
16
Second, Apotex claims that public policy considerations
weigh against applying res judicata in this case. We disagree.
There is no general public policy exception to the operation of
res judicata. See Federated Dep't Stores, Inc. v. Moitie, 452
U.S. 394, 401 (1981) (rejecting the court of appeals' reliance on
"simple justice" and "public policy" in declining to apply res
judicata, and stating: "There is simply 'no principle of law or
equity which sanctions the rejection by a federal court of the
salutary principle of res judicata.'") (quoting Heiser v. Woodruff,
327 U.S. 726, 733 (1946)). If there is any "public policy"
exception to res judicata, it applies only in very limited
circumstances, e.g., in cases implicating significant questions of
constitutional law where there has been a change in controlling
legal principles. See Hardison, 655 F.2d at 1288-89.
The only argument Apotex offered in its opening brief as to
why this case might fit within the scope of a public policy
exception to res judicata is that, absent a favorable ruling from
this court, FDA will continue to apply the 180-day generic
marketing exclusivity provision under § 355(j)(5)(B)(iv) in a
way that defies congressional intent. Obviously, this argument
does not save Apotex from the res judicata bar in this case. The
statutory question raised by Apotex is no doubt compelling. But
its resolution must await another day, i.e., when a suit is
properly before the court calling into question FDA's
interpretation of 21 U.S.C. § 355(j)(5)(B)(iv).
Finally, because we affirm the District Court's judgment on
res judicata grounds, we vacate the District Court's alternative
holding addressing the merits of the statutory interpretation
question.
III. CONCLUSION
Res judicata bars Apotex from bringing this suit.
Therefore, we affirm the judgment of the District Court on this
ground alone. We vacate the District Court's alternative holding
17
purporting to resolve the parties' dispute over the interpretation
of 21 U.S.C. § 355(j)(5)(B)(iv).
So ordered.