Amer Bioscience Inc v. Thompson, Tommy G.

United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued September 17, 2001 Decided November 6, 2001

No. 01-5125

American Bioscience, Inc.,
Appellant

v.

Tommy G. Thompson,
Secretary of Health and Human Services, et al.,
Appellees

Appeal from the United States District Court
for the District of Columbia
(00cv02247)

Jacqueline H. Eagle argued the cause for appellant. With
her on the briefs were Joseph F. Coyne, Jr., Carlton A.
Varner, Arthur Y. Tsien, David F. Weeda, and Robert F.
Green.

 Howard S. Scher, Attorney, United States Department of
Justice, argued the cause for appellee. With him on the brief
were Kenneth L. Wainstein, United States Attorney, Douglas
N. Letter, Litigation Counsel, Michael M. Landa, Acting
Chief Counsel, Food & Drug Administration, and AnnaMarie
Kempic, Associate Chief Counsel.

Richard M. Cooper argued the cause for appellees Baker
Norton Pharmaceuticals, Inc. and IVAX Pharmaceuticals,
Inc. With him on the brief was Philip A. Sechler.

Before: Tatel, Circuit Judge; Silberman and Williams,*
Senior Circuit Judges.

Opinion for the Court filed by Senior Circuit Judge
Silberman.

Silberman, Senior Circuit Judge: American Bioscience,
Inc., appeals from the district court's denial of its request for
preliminary injunctive relief. Appellant argues that the Food
and Drug Administration's decision to approve intervenor-
defendant Baker Norton Pharmaceutical's Abbreviated New
Drug Application (ANDA) for a generic version of the cancer
treatment Taxol was arbitrary and capricious. We agree and
vacate that approval.

I.

This case is here for the second time. See American
Bioscience, Inc. v. Thompson, 243 F.3d 579 (D.C. Cir. 2001).
American Bioscience is a pharmaceutical research firm that
has developed a patented process for delivering safer and
more effective dosage forms of Taxol. Bristol-Myers Squibb
Company holds the patent on and FDA approval of Taxol
itself, a drug that has generated billions of dollars in sales.
Bristol-Myers intervened in the district court proceeding for
the limited purpose of providing information. Appellees Bak-
er Norton Pharmaceuticals, Inc. (BNP) and Zenith Goldline
Pharmaceuticals, Inc., who are corporate affiliates and hold

__________
* Senior Judge Williams was in regular active service at the time
of oral argument.

ANDAs for generic versions of Taxol, intervened as defen-
dants.

This dispute arises out of the complex relationship between
the FDA's approval process for generic drugs and patent law.
A company wishing to market a new (or "pioneer") drug must
seek FDA approval, usually by completing a New Drug
Application. The NDA is expensive and time-consuming,
requiring data from tests showing the drug's safety and
effectiveness. Prior to 1984, a firm that wished to make a
generic version of an approved drug was required to file a
new NDA, complete with new safety and effectiveness stud-
ies. In 1984, Congress enacted the Hatch-Waxman Amend-
ments,1 which introduced the Abbreviated NDA and allowed a
generic drug ANDA to rely on the pioneer NDA's safety and
effectiveness studies. These amendments also provide that a
competitor may use and manufacture an approved and pat-
ented drug, for the purpose of developing a generic version,
without infringing that patent.

The Hatch-Waxman Amendments also sought to afford an
NDA holder some patent protection, to lower the risk to
innovation posed by the simplified ANDA process. NDAs
are required to contain a list of any patents which claim the
drug or which claim a method of using such a drug and with
respect to which a claim of patent infringement could reason-
ably be asserted--but that includes patents held by those
other than the NDA holder. The FDA publishes all patent
listings in the Approved Drug Products With Therapeutic
Equivalence (the "Orange Book"). For "each patent which
claims" the pioneer drug, an ANDA must certify: (1) that no
patent has been filed with the FDA; (2) that the patent has
expired; (3) that the patent has not expired, but will expire
on a particular date; or (4) that the patent is either invalid or
the generic drug will not infringe it (a "Paragraph IV certifi-
cation"). When an ANDA applicant files a Paragraph IV
certification, it must also certify to the FDA that it will give
notice to the patent holder. That notice must include a

__________
1 The Drug Price Competition and Patent Term Restoration Act
of 1984, Pub. L. No. 98-417, 98 Stat. 1585 (1984).

detailed statement of the factual and legal basis of the
applicant's opinion that the patent is not valid or will not be
infringed and must be given at the same time the certification
is submitted to the FDA. Filing a Paragraph IV certification
can constitute patent infringement. Upon receipt of notice of
a Paragraph IV certification, the patent holder has 45 days in
which to file an infringement suit. If the patent holder does
not file within that time period, the FDA may immediately
approve an otherwise conforming ANDA. If, on the other
hand, the patent holder does sue within 45 days, the FDA
may not approve the ANDA for 30 months, or until the patent
dispute has been resolved, whichever is sooner. The first
ANDA filed and approved gets a 180-day period of market
exclusivity.

If a qualifying patent issues at a later date--after the NDA
is approved--the NDA holder must inform the FDA within 30
days of the patent's issuance. See 21 U.S.C. s 355(c)(2). But
if the NDA holder fails to so notify the FDA, an ANDA
applicant is excused, according to the FDA's late-listing regu-
lation, from amending its patent certification to reflect the
new patent so long as the ANDA had an "appropriate" patent
certification on file. As shall be apparent, however, only the
NDA holder has the obligation (and the right) to list the new
patent--not the patent holder if it is another company. In
this case, if Bristol-Myers listed American Bioscience's pat-
ent within 30 days of its issuance, BNP was required to
certify to that patent, potentially leading to a patent infringe-
ment suit and 30-month stay.2

In the event a person disputes the accuracy or relevance of
patent information published by the FDA in the Orange
Book, he must first notify the agency, in writing, stating the
grounds for disagreement. The FDA will then request that
the applicable NDA holder confirm the correctness of the
patent information or omission of patent information. Unless
the NDA holder withdraws or amends its patent information

__________
2 BNP argues that the statute does not allow for consecutive 30-
month stays, even if there are subsequent Paragraph IV certifica-
tions. The FDA did not adopt this reading.

in response to the FDA's request, the agency will not change
the patent information in the list. And if the NDA holder
does not change the patent information, an ANDA must,
despite any disagreement as to the correctness of the patent
information, contain an appropriate certification for each list-
ed patent. The FDA, pursuant to longstanding practice and
its own regulations, and based on its acknowledged lack of
expertise and resources, has refused to become involved in
patent listing disputes, accepting at face value the accuracy of
NDA holders' patent declarations and following their listing
instructions.

The FDA approved Bristol-Myers' NDA to manufacture
and distribute Taxol, an anti-cancer drug with the active
ingredient paclitaxel, in 1992. Five years later, BNP submit-
ted an ANDA for a generic version of Taxol. Bristol-Myers
instituted patent infringement proceedings against BNP with-
in the 45-day statutory window, triggering the 30-month
stay, which expired in June 2000. The record does not
reveal, and counsel for the FDA could not explain, why the
FDA did not approve BNP's ANDA promptly upon expiration
of the stay. But on August 1, 2000, American Bioscience
received U.S. Patent Number 6,906,331 for a new process that
purported to permit a patient to receive higher doses of Taxol
with fewer side effects. Bristol-Myers did not immediately
list the new patent.3 Ten days after the patent issued,
American Bioscience sued Bristol-Myers in the United States
District Court for the Central District of California request-
ing a TRO compelling Bristol-Myers to submit the '331
patent for listing in the Orange Book, which the court grant-
ed, ordering Bristol-Myers to "immediately take all steps
under its control to cause the FDA to list in its 'Orange Book'
[American Bioscience's] Taxol Patent, subject to the proviso
that, unless Plaintiff carries its burden of proof on the [Order
to Show Cause], [Bristol-Myers] shall then take all steps

__________
3 We are told that correspondence between American Bioscience
and Bristol-Myers indicates that Bristol-Myers refused to list the
patent without a court order, but that is not part of the administra-
tive record.

under its control to cause the de-listing of the Taxol Patent
from the FDA's Orange Book." That same day, Bristol-
Myers sent a letter to the FDA, stating that it was submitting
the '331 patent for listing "pursuant to" the August 11 court
order and "in accordance with" the voluntary listing provi-
sion. Bristol-Myers also submitted a patent declaration with
the listing.

On August 14, 2000, BNP filed a Paragraph IV certification
for the '331 patent but contrary to the statute it did not notify
either Bristol-Myers or American Bioscience. One week
later, the California court held a hearing at which Bristol-
Myers, American Bioscience and BNP (as a proposed interve-
nor) were present.4 American Bioscience then learned for
the first time of BNP's Paragraph IV certification. On
August 28, 2000, the FDA tentatively approved BNP's
ANDA, subject to resolution of the '331 patent issues. Mean-
while, after two hearings, the California court determined
that it lacked "jurisdiction" over American Bioscience's suit
because the Food Drug and Cosmetic Act did not provide
American Bioscience a private right of action. On September
7, 2000, the California court dissolved the TRO and ordered
Bristol-Myers "[p]ursuant to the condition in the TRO and in
order to restore the status quo ... [to] use its best efforts to
cause the delisting of [American Bioscience's] '331 Patent
from the Orange Book." It recommended to the FDA that it
toll the amount of time the TRO was in place and stayed its
order until September 13, 2000.

Also on September 7, 2000, American Bioscience sued BNP
for patent infringement and informed the FDA the next day
but the FDA did not grant a stay. On September 11, 2000,
Bristol-Myers wrote the FDA a letter stating that it was
listing the '331 patent "pursuant to" the voluntary listing
provision. Then three days later, on September 14, 2000,
Bristol-Myers wrote the FDA another letter, which stated

__________
4 BNP repeatedly refers to the transcript of this hearing in
support of its allegation that Bristol-Myers and American Biosci-
ence colluded to obtain temporary injunctive relief. This transcript
is not a part of the administrative record.

that it was de-listing the '331 patent to the extent it was listed
pursuant to the California court's TRO, but that it did not
mean to affect the continued and continuous listing of the
patent. That same day, after receiving a phone call from the
FDA, BNP withdrew its Paragraph IV certification.5 And
the next day, the FDA approved BNP's ANDA. In its
approval letter, the FDA referenced BNP's September 8 and
September 14 amendments, but did not otherwise discuss
the '331 patent.

American Bioscience then brought this action, claiming that
the FDA's actions were contrary to the Administrative Proce-
dure Act. Specifically, it asserted that the '331 patent was
timely and continuously listed from August 11, 2000, there-
fore the FDA's refusal to grant a stay and its approval of
BNP's ANDA were contrary to law; that the FDA's decision
not to toll the 30-day listing window was arbitrary and
capricious; that BNP could not benefit from the late-listing
regulation because a certification could not be "appropriate"
without the required notice; and that the FDA exceeded its
regulatory authority in promulgating the late-listing regula-
tion. Appellant requested a declaration that approval be
stayed; injunctive relief ordering the FDA to rescind the
approval; attorney fees and costs; and any other just and
proper relief. The district court granted BNP's motion to
intervene and allowed Bristol-Myers to intervene to provide
additional information.

The FDA defended on the ground that Bristol-Myers had
not "timely" listed the '331 patent and therefore BNP did not
have to certify to it. The agency had not previously disclosed
the basis for its approval, nor did it provide a certified
administrative record. After oral argument, the district court
issued a written memorandum and opinion denying American
Bioscience's requested relief on the ground that it had failed
to show that it was likely to prevail on the merits because the
FDA's interpretation and application of the late-listing regu-

__________
5 Between August 14, 2000 and September 14, 2000, the FDA had
at least seven telephone conversations with BNP.

lation was not plainly erroneous or inconsistent with the
regulation, which was itself valid.

American Bioscience appealed and we vacated the district
court's decision and remanded because "there [was] nothing
in the FDA's approval letter to indicate how it interpreted
[the late-listing] regulation." American Bioscience, 243 F.3d
at 582. We did not know whether the FDA approved the
application because it considered the '331 patent to have been
de-listed; whether it considered the court-ordered listing
ineffective for purposes of the Hatch-Waxman Act; whether
it treated the application as one covered by the late-listing
regulation; or, if it did, why it thought the regulation applied,
observing that, for all we knew, the FDA made a "clerical
error" in approving the application even though it thought
that the '331 patent had been continually listed. We held that
the district court, "before assessing American Bioscience's
probability of success on the merits, should have required the
FDA to file the administrative record and should have deter-
mined the grounds on which the FDA granted [BNP]'s
application." Id. We left to the district court the determina-
tion of how best to proceed on remand in light of what the
administrative record revealed.

On April 6, 2001, the FDA certified the administrative
record which included a declaration by Gary J. Buehler, the
acting director of the FDA's Office of Generic Drugs, Center
for Drug Evaluation and Research. Buehler focused on the
court orders in his explanation of the agency's rationale. In
his view, the September 7 order compelled Bristol-Myers to
de-list the '331 patent "to restore the status quo." He
concluded that because the court order directing Bristol-
Myers to submit the patent to the FDA was dissolved, and
Bristol-Myers withdrew the original submission, the August
11 listing was "without effect." Accordingly, because Bristol-
Myers had failed to timely list the patent, BNP was entitled
to the benefit of the late-listing regulation. The FDA did not
follow the court's recommendation that it toll the period in
which Bristol-Myers could timely list because the FDA was
not a party to the California litigation; he was not sure that
the FDA had the authority to toll the statutory time limit;

tolling would set an undesirable precedent; and he saw no
reason why Bristol-Myers could not have "voluntarily" listed
the '331 patent during the 30-day statutory period.

Buehler quoted the passage from the September 14 letter
in which Bristol-Myers stated that it was "[t]hereby with-
drawing" the August 11 listing to the extent that listing was
compelled by the TRO, but did not address the significance of
Bristol-Myers' statement that it had not intended to affect
the continued and continuous listing of the patent. Buehler
also said that the FDA received letters pertaining to "this
issue" (presumably the issue of approving a generic version of
Taxol), and that he had been made aware of the concerns of
the Federal Trade Commission and some members of the
public about the potential for the aggressive use of patent
listings to delay generic competition.6 The administrative
record consists in large part of the tentative and final approv-
al letters for BNP's ANDA; the August 11, 2000 TRO and
the September 7, 2000 order; the August 11, 2000, September
11, 2000, and September 14, 2000 letters from Bristol-Myers
to the FDA; correspondence from BNP to the FDA outlining
BNP's concerns about the '331 patent, certifying to the '331
patent, and withdrawing the certification to the '331 patent;
the Federal Trade Commission's amicus brief in the Califor-
nia case; records of telephone conversations between the
FDA and BNP; and letters from the National Organization
for Women Foundation, the Generic Pharmaceutical Associa-
tion, and Senator Kennedy expressing their concerns about
delay in the availability of generic drugs. The administrative
record does not contain either the transcripts of the hearings
in the California court, or any correspondence between
Bristol-Myers and American Bioscience.

__________
6 After American Bioscience filed suit and before the FDA filed a
certified administrative record, the FDA approved a second poten-
tially infringing ANDA for Zenith Goldline and granted "tentative"
approval to a third. BNP apparently waived its 180-day statutory
market exclusivity as to its corporate affiliate Zenith Goldline, but
not with respect to the third ANDA.

 Shortly after the FDA certified the administrative record,
American Bioscience renewed its request for preliminary
injunctive relief, which the district court denied. The court
held that American Bioscience failed to show that it would
suffer irreparable harm and was not substantially likely to
prevail on the merits. It acknowledged that the administra-
tive record did not include any "overt reference to the
decisions at issue," but concluded that the record implicitly
supported the FDA's version of events (as set forth by
counsel) and that the FDA's decision to approve BNP's
ANDA was supported by "inferences" that could be drawn
from the administrative record.

II.

Appellant makes two basic arguments. The FDA acted
contrary to law by approving BNP's application in light of
Bristol-Myers' listing of the '331 patent. It was arbitrary
and capricious for the agency to have concluded that Bristol-
Myers' September 14 letter revoked the August 11 listing.
Secondly, American Bioscience argues that even if the Sep-
tember 11 listing were legitimately thought to be Bristol-
Myers' first listing, BNP could not benefit by the late-listing
regulation since it did not have an "appropriate" patent
certification filed (as it had never given notice). We need not
reach appellant's second argument because we think it is
clearly correct on its first.

Before discussing the merits we must dispose of the gov-
ernment's argument as to appellant's asserted lack of irrepa-
rable injury. Normally when a party seeks a preliminary
injunction in district court the district judge properly bal-
ances the likelihood of the plaintiff prevailing on the merits
against the severity of the injury the plaintiff will suffer if
relief is denied. But that procedure assumes that the district
judge will be obliged to make a decision before the complete
case is presented--before all the evidence is submitted.

As we have repeatedly recognized, however, when a party
seeks review of agency action under the APA, the district

judge sits as an appellate tribunal.7 The "entire case" on
review is a question of law. See, e.g., Marshall County
Health Care Auth. v. Shalala, 988 F.2d 1221, 1226 (D.C. Cir.
1993) (holding that in agency review context there was no real
distinction between questions presented in Rule 12(b)(6) mo-
tion to dismiss and motion for summary judgment); Univer-
sity Medical Center of S. Nevada v. Shalala, 173 F.3d 438,
440 n.3 (D.C. Cir. 1999) (explaining that when reviewing
agency action the question of whether the agency acted in an
arbitrary and capricious manner is a legal one which the
district court can resolve on the agency record, regardless of
whether it is presented in the context of a motion for judg-
ment on the pleadings or in a motion for summary judgment);
James Madison Ltd. v. Ludwig, 82 F.3d 1085, 1096 (D.C. Cir.
1996), cert. denied, 519 U.S. 1077 (1997) (holding that issues
that appellant argued were issues of fact precluding summary
judgment were issues of law in the context of agency review);
County of Los Angeles v. Shalala, 192 F.3d 1005, 1011 (D.C.
Cir. 1999), cert. denied, 530 U.S. 1204 (2000) (holding that rule
of finality does not apply to bar appellate review of the
district court's finding that the agency action was arbitrary
and capricious even though that court had not yet resolved
the issue of remedy). Absent very unusual circumstances the
district court does not take testimony. See, e.g., Citizens to
Preserve Overton Park, Inc. v. Volpe, 401 U.S. 402 (1971);
James Madison, 82 F.3d at 1096.

If an appellant has standing--which is undeniable here--
and prevails on its APA claim, it is entitled to relief under
that statute, which normally will be a vacatur of the agency's
order. See, e.g., Association of Battery Recyclers, Inc. v.
EPA, 208 F.3d 1047, 1061 (D.C. Cir. 2000). Cf. Canadian
Pacific Railway Co. v. Surface Transp. Bd., 197 F.3d 1165
(D.C. Cir. 1999). To be sure, although appellant based its
cause of action on the APA, it introduced a good deal of

__________
7 Which is not to say that a motion for preliminary injunction
against an agency is never appropriate. See, e.g., CityFed Finan-
cial Corp. v. Office of Thrift Supervision, 58 F.3d 738 (D.C. Cir.
1995) (involving Office of Thrift Supervision's decision to issue a
temporary cease and desist order against appellant freezing virtual-
ly all of its assets).

confusion by seeking an injunction (as well as other appropri-
ate relief). But, whether or not appellant has suffered irrepa-
rable injury, if it makes out its case under the APA it is
entitled to a remedy.8

We implicitly recognized this point before when we ordered
the remand of the case for the agency to produce a record
without consideration as to whether appellant's injury was
irreparable. See American Bioscience, 243 F.3d 579. The
challenged action is an "informal adjudication" which is the
administrative law term for agency action that is neither the
product of formal adjudication or a rulemaking. See, e.g., id.
at 582; United States v. Mead Corp., 121 S. Ct. 2164, 2178 n.1
(2001) (Scalia, J., dissenting). Ever since Overton Park and
Camp v. Pitts, 411 U.S. 138 (1973), government agencies
which issue orders subject to appeal under the APA typically
include some explanation--however short--that will provide a
record on appeal. After examining the Buehler declaration,
which purports to explain the FDA's action in this case, it is
perhaps not surprising that the agency took the action it did
originally without explanation. For assuming that that decla-
ration satisfies our demand for the record before the agency,
we find it sadly inadequate to sustain the agency's action.

As we noted, and the parties agree, the FDA has a
longstanding policy not to get involved in patent disputes. It
administers the Hatch-Waxman Amendments in a ministerial
fashion simply following the intent of the parties that list
patents. In this case, however, Buehler appears to have
relied on his reading of the district court order-to which the
agency was not a party--to trump Bristol-Myers' stated
intention.9 His declaration notes that the district court on
September 7 "dissolved the TRO, dismissed [American Biosci-
ence's] complaint and ordered [Bristol-Myers] to delist the

__________
8 Since under 28 U.S.C. s 1657(a) the granting or denying of a
preliminary injunction is the basis for an expedited appeal the
district courts should be careful--in such a case as this--not to do
so.

9 Paradoxically, in rejecting the district court's tolling recommen-
dation Buehler emphasizes the California district court had no
jurisdiction and the FDA was not a party.

'331 patent from the Orange Book to restore the status quo."
And then "on September 14, 2000 [Bristol-Myers] submitted
a letter to FDA to comply with the court order to delist the
patent. The letter states '[Bristol-Myers] hereby withdraws
the Original Listing to the extent that listing was compelled
by the TRO.' " Because of that sequence, the "FDA consid-
ered [Bristol-Myers'] first submission of the patent on Au-
gust 11, 2000 to be without effect."

But Buehler omits reference to much of the September 14
letter which clearly indicates that Bristol-Myers' original
filing of August 11 had a bifurcated purpose-to comply with
the court order and to voluntarily list the '331 patent and
accordingly it was abrogating the first but not the second.

Thus, Bristol-Myers' counsel stated:

Although that submission (the "Original Listing") (At-
tachment A) was made in accordance with a Temporary
Restraining Order ("TRO") entered on that date by the
United States District Court for the Central District of
California, it was also timely filed in full compliance with
all governing statutory and regulatory requirements for
voluntary patent listing. It contained all required listing
information, was presented in the format recommended
by the agency for voluntary listings, and was supported
by a declaration signed by Steven Reiter, counsel for the
patent owner, using the precise language required by
regulations set forth at 21 C.F.R. 314.53(c)(2).

And at the end of the letter, after the sentence Buehler
quoted, counsel states: "This action does not affect the
continued and continuous listing of the patent ...," which
unequivocally indicates what Bristol-Myers meant when it
limited its withdrawal of the listing only "to the extent that
listing was compelled by the TRO ..." As such Buehler,
speaking for the FDA, seems to wholly ignore Bristol-Myers'
stated intent. He gives no forthright justification for such a
blatantly artificial reading of its letters.10

__________
10 The government contends that Bristol-Myers' letter of Septem-
ber 11 again listing the '331 patent suggests that it realized the

 He seems to implicitly suggest that Bristol-Myers' stated
intent is somehow inconsistent with the California district
court's order and on appeal the government boldly contends
that that intent--to continue its listing on a voluntary basis--
is "unacceptable" without explaining why that should be so.
But there is nothing in the California district court's original
order that prevented Bristol-Myers from changing its mind
and deciding to list voluntarily in addition to complying with
the court order. Nor is there anything in the order directing
the return to the status quo that would extend to requiring
Bristol-Myers to abrogate such voluntary action. We, of
course, owe no deference to an agency's reading of judicial
orders or decisions, see, e.g., United States Dep't of Justice v.
FLRA, No. 00-1433, 2001 WL 1180726, *2 (D.C. Cir. Oct. 9,
2001); New York v. Shalala, 119 F.3d 175, 180 (2d Cir. 1997),
but even if we did we would not accept the reading the
government urges upon us because it is unreasonable. In-
deed, it is not at all clear to us that the FDA, under its
regulations, would be authorized to reject the obvious intent
of an NDA holder even if it acted directly contrary to a court
order. Certainly, the FDA points us to no authority upon
which it could rely to do so.

Intervenor BNP in its brief (and its letters to the FDA)
would have us believe that appellant and Bristol-Myers are in
cahoots, that the California lawsuit was a Kabuki play and
that they have a common objective to frustrate the introduc-
tion of generic versions of Taxol. The difficulty with these
assertions--besides being not proven--is that the FDA
(Buehler) did not rely on this rationale. Nor is it clear that
the FDA, as opposed to a district court in an antitrust or
patent infringement case, could adjudicate such a claim.

__________
district court order would result in the elimination of the August 11
listing. But the FDA (Buehler) did not offer that reasoning. In
any event, it seems obvious to us that Bristol-Myers' September 11
letter was simply an effort to add a belt to suspenders and is even a
greater indication that it never intended to completely de-list the
'331 patent.

 To be sure, Buehler hints in his declaration that he has
dark suspicions by saying that he "was also made aware of
the concerns of the Federal Trade Commission and some
members of the public of the potential for the aggressive use
of patent listings to delay generic competition." But such
hints are hardly the stuff of reasoned decisionmaking. We
therefore do not see how we can give any weight to BNP's
allegations nor the letter from other members of the public
opposing appellant's position.

Which brings us to the remedy. We have already directed
the district court to remand this case once to compile a
record. See American Bioscience, 243 F.3d at 582-83. That
is consistent with our practice of remanding without vacating
when we are unsure of the grounds the agency asserts to
defend its action (and, perhaps, where we perceive that a
ground poorly articulated might be sufficient to sustain the
action). See, e.g., Checkosky v. SEC, 23 F.3d 452, 454 (D.C.
Cir. 1992); City of Los Angeles, 192 F.3d at 1023; Radio-
Television News Directors Assoc. v. FCC, 184 F.3d 872, 887-
88 (D.C. Cir. 1999). But at this point we think the only
appropriate course is to vacate the action appellant chal-
lenges--the FDA's approval of BNP's ANDA. We frankly do
not know what recourse is left to the FDA or other govern-
ment agencies to take any steps that would affect the market-
ing of generic versions of Taxol. But we are convinced that
the FDA's order, in this case, was arbitrary and capricious
and must be vacated.

* * * *

Accordingly, the district court is directed to vacate the
FDA's order and remand to the agency.

So ordered.