Source: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-caDC-94-05041/USCOURTS-caDC-94-05041-0/pdf.json

Nature of Suit Code: 890
Nature of Suit: Other Statutory Actions
Cause of Action: 

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United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued March 17, 1995 Decided August 25, 1995

No. 94-5041

A.L. PHARMA, INC.,

APPELLANT 

v.

DONNA E. SHALALA, ET AL.,

APPELLEES 

Appeal from the United States District Court

for the District of Columbia

(83cv01603)

James H. Wallace Jr., with whom James M. Johnstone and Richard L. McConnell Jr. were on the

briefs, argued the cause for appellant.

Jeffrey B. Chasnow, Attorney, United States Department of Justice, with whom Frank W. Hunger,

Assistant Attorney General, and Catherine L. Copp, Associate Chief Counsel, Food and Drug

Administration, were on the brief, argued the cause for appellees.

Before EDWARDS, Chief Judge, and BUCKLEY and GINSBURG, Circuit Judges.

Opinion for the court filed by Circuit Judge BUCKLEY.

BUCKLEY, Circuit Judge: To gain Food and Drug Administration approval for the sale of a

new animal drug, an applicant must demonstrate that it is both safe and effective for itsintended uses.

Finding that this standard had been met, the FDA approved for sale a drug produced by Philips

Roxane, Inc., which is marketed to improve growth and feed efficiency in broiler chickens. Appellant

A.L. Pharma, Inc. ("A.L."), a competitor of Philips Roxane, petitioned the FDA to reverse its

approval and, receiving no satisfaction fromthe agency,sought reliefin the district court. The district

court granted summary judgment for the agency, and A.L. appeals. We affirm in part and reverse and

remand in part with instructions to the district court to return the matter to the FDA for a more

reasoned justification of its actions.

I. BACKGROUND

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A. New Animal Drug Application No. 128-550

The tortured story of this litigation begins in 1981, when Philips Roxane first sought FDA

permission to sell two chicken feed mixes containing bacitracin zinc, a drug used to increase the rate

of growth and feed efficiency in poultry. The Food, Drug and Cosmetic Act ("FDCA") provides that

any new animal drug is considered unsafe prior to receiving FDA approval for its intended use. 21

U.S.C. § 360b(a)(1)(A) (1988). To secure such approval, the FDCA requires the applicant to file

a New Animal Drug Application ("NADA") that includes information demonstrating both the safety

and the efficacy of the drug. Id. § 360b(d)(1)(A), (B) & (E) (1988). Philips Roxane's bacitracin zinc

feed mixes are regulated by these provisions, and the company accordingly filed New Animal Drug

Application No. 128-550 ("NADA 128-550") in order to obtain FDA approval to market the

products.

In the early 1970's, the Animal Health Institute ("AHI"), an industry trade association,

coordinated a safety study on bacitracin zinc, the results of which were to be shared by the

pharmaceutical companies that contributed to the research costs. See A.L. Labs., Inc. v. Philips

Roxane, Inc., 803 F.2d 378, 380 (8th Cir. 1986). In 1973, copies of the study were sent to the FDA

and placed in what the agency calls its "master files" for subsequent use by the study's sponsors.

When Philips Roxane submitted its application, it referred to one of these master files, MF 3578, as

evidence that its product met the FDA's safety requirement. See A.L. Labs., 803 F.2d at 380. There

is no dispute that the AHI study provided an adequate basis for the FDA to determine that Philips

Roxane's product was "safe for use under the conditions prescribed, recommended, or suggested in

the proposed labeling," as required by the FDCA. 21 U.S.C. § 360b(d)(1)(A). 

That study, however, did not establish that PhilipsRoxane's product met the agency's efficacy

requirement. The FDCA conditions the FDA's approval of a NADA on

substantial evidence that the drug will have the effect it purports or is represented to

have under the conditions of use prescribed, recommended, or suggested in the

proposed labeling thereof....

21 U.S.C. § 360b(d)(1)(E). It defines "substantial evidence" to mean

evidence consisting of adequate and well-controlled investigations, including field

investigation, by experts qualified by scientific training and experience to evaluate the

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effectiveness ofthe drug involved, on the basis of which it could fairly and reasonably

be concluded by such experts that the drug will have the effect it purports or is

represented to have under the conditions of use prescribed, recommended, or

suggested in the labeling or proposed labeling thereof.

21 U.S.C. § 360b(d)(3) (1988). To paraphrase, then, a NADA generally must include evidence that

the applicant's drug is not only safe, but that it will do what the applicant claimsit will do. The FDA's

regulations mirror the statute, requiring manufacturers to provide "substantial evidence" of the

"effectiveness of the drug involved...." 21 C.F.R. § 514.111(a)(5)(i) (1994).

In 1970, the National Academy of Sciences/NationalResearch Council conducted a study of

the efficacy of bacitracin zinc drugs. 35 Fed. Reg. 11,531 (1970). Based on the Academy's findings

concerning the effectiveness of bacitracin zinc products used to increase the rate of growth and feed

efficiencyin poultry, the FDAconcluded that the drug "c[ould] be moved into the effective category";

it also provided, by regulation, that it would approve applicationsfor bacitracin zinc drugs "identical"

to the one tested by the Academy if, in lieu of direct proof of effectiveness, the applicant submits

"bioequivalency or similar data ... as suggested in the guideline for submitting NADA's for generic

drugs reviewed by the [Academy]." 46 Fed. Reg. 37,043, 37,044 (1981) (codified at 21 C.F.R. §

558.78 (1994)). This regulation provided Philips Roxane with an important shortcut to FDA

approval. Instead of conducting studies to prove that its particular product actually would promote

growth and feed efficiency in chickens, Philips Roxane had the option of demonstrating that its

product was "bioequivalent" to the "benchmark" product that the Academy had found to be effective

for those purposes.

Thisregulatory shortcut, of course, begs the question of what precisely a manufacturer must

prove forthe FDAto deemits product "bioequivalent" and therefore effective. Unfortunately, neither

the regulation nor the guideline referred to in the FederalRegister sheds any light on the matter. The

guideline merely instructs the applicant to submit "bioequivalency data which compares and

establishesthe similarity of the generic drug to that reviewed by the Academy preferably in the target

animal."

To establishbioequivalency, PhilipsRoxane commissionedDr. John Prescott of the University

of Guelph in Ontario, Canada, to conduct a study comparing its bacitracin zinc product with that of

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the benchmark product manufactured by International Minerals & Chemical Corp. ("International

Minerals"). To this end, Dr. Prescott tested the ability of the Philips Roxane and International

Minerals products to prevent the experimental inducement of a disease organism, necrotic enteritis,

in a population of chickens, and found the two equally effective for that purpose.

In 1982, the FDA issued a rule approving NADA 128-550, based on its conclusion that

Philips Roxane's bacitracin zinc product was safe and effective for increasing the rate of weight gain

and improving feed efficiency in chickens. 47 Fed. Reg. 35,187 (1982). The agency noted that the

Philips Roxane and International Minerals feed mixes were similar and determined that the Prescott

necrotic enteritis study "establishes bioequivalency" between the two. Id.

B. A.L. Pharma's Challenge

Over the past thirteen years, A.L. hasfiled no fewer than four citizen petitions with the FDA,

see 21 C.F.R. § 10.25(a), 10.30 (1994), requesting the withdrawal of the rule approving Philip

Roxane's application, each of which the agency has rejected. After the FDA's denial of A.L.'s first

citizen petition, A.L. brought suit in the U.S. District Court for the District of Columbia seeking a

declaration that the approval of Philip Roxane's application was unlawful and an injunction setting

it aside. That suit was amended on subsequent occasions to incorporate the agency's denial of

subsequent citizen petitions. Although A.L. has challenged the approval of the application on a

number of grounds, it presses only two on appeal.

The first ofthese hasitsrootsin an allegation in A.L.'sinitial citizen petition that it, not Philips

Roxane, owned the safety data in MF 3578 and that the FDA'sreliance on it wastherefore improper.

The FDA responded that itsrecordsindicated that Philips Roxane owned the MF 3578 data and that

any dispute over the ownership of that information was "more appropriately resolved" in a civil suit

for misappropriation of trade secrets that A.L. was then pursuing against Philips Roxane in the U.S.

District Court for the Western District of Missouri than in an administrative proceeding. Letter from

Joseph P. Hile, FDA Assoc. Commissioner for Regulatory Affairs, to James J. Johnstone, Esq., and

Bruce L. McDonald, Esq., Attorneys for A.L. Pharma ("1982 Petition Denial"), reprinted in Joint

Appendix ("J.A.") at 137.

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A.L. eventually prevailed in that lawsuit. On appeal, the Eighth Circuit upheld an award of

$785,000 in punitive damages and a 51-month injunction against Philips Roxane's sale of bacitracin

zinc to compensate for the time it would have taken the company to replicate the safety data and then

secure FDA approval based on those independent results. A.L. Labs., 803 F.2d at 383-85. With this

judgment in hand, A.L. returned to the FDA seeking rescission of its approval of Philips Roxane's

application. By this time, however, the application no longer relied on MF 3578. Philips Roxane had

since purchased fromanothersponsor ofthe AHIstudy the right to refer to its copy of the safety data

and had amended its application to refer to that alternative file. The FDA ruled that revoking its

approval would serve no public health purpose and that neither the FDCA nor the citizen petition

rules contemplated the use of the FDA's administrative procedures for punitive action against an

animal drug manufacturer.

Second, A.L. maintains that the Prescott Study did not establish the bioequivalency of the

Philips Roxane bacitracin zinc and the International Minerals benchmark product. In support of its

initial citizen petition, the company submitted affidavits and letters of sixteen highly credentialed

scientists, all of whom questioned the bioequivalency conclusion. The agency responded that the

Prescott Study's demonstration that the two drugs' biological activity against the necrotic enteritis

disease organism were not significantly different, "together with manufacturing data and the results

of microbiological assays, adequately establish that drugs from the two sources will be equally

effective for increased weight gain and improved feed efficiency." 1982 Petition Denial at 2.

A.L. argued, in the district court, that the FDA acted arbitrarily in denying its petitions

because the agency misapplied its "bioequivalency" standard and, in any event, that it violated its

regulations when it declined to withdraw its approval of the application upon learning that Philips

Roxane had falsely claimed that it owned the safety data. In December 1993, the district court

granted the agency's motion for summary judgment. A.L. Labs. v. Shalala, No. Civ. A. 83-1603

(D.D.C. Dec. 21, 1993) ("Memorandum Opinion"). The court held that the FDA properly permitted

Philips Roxane to substitute the untainted safety data for the identical data owned by A.L., and that

there was nothing in the agency's rules that obliged it to withdraw approval of the application based

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on the ownership dispute. Id. at 12-13. The court also deferred to the agency's bioequivalency

judgment, noting that the record indicated that the "FDA evaluated alternative means of establishing

bioequivalence" before approving the Prescott Study and deciding that "this Court is not in a position

to decide which scientific method is preferable." Id. at 11. A.L. then filed this appeal.

II. DISCUSSION 

A. The Safety Data

A.L. contendsthat the FDA failed to follow its own regulations when it refused to rescind the

application as a consequence ofPhilipsRoxane'smisrepresentationofits ownership ofthe safetydata.

A.L. relies on an FDA regulation that provides:

Any reference to information furnished by a person other than the applicant may not

be considered unless its use is authorized in a written statement signed by the person

who submitted it.

21 C.F.R. § 514.1(a) (1994).

Pointing to itssuccessfulmisappropriationsuit inthe EighthCircuit, A.L. arguesthat the FDA

never should have permitted Philips Roxane to rely on the safety data in MF 3578 and that it violated

itsregulation byso doing. The remedy, A.L. urges, is rescission of the FDA's approval of the NADA,

thus requiring Philips Roxane to file a new application and shepherd it through another approval

process.

The initial problem with A.L.'s theory is that it incorrectly presumes that establishing its

ownership rights in MF 3578, which it did in its civil suit, constitutes proof that the FDA failed to

abide by its regulation. By its terms, the regulation prevents the agency from using data submitted

by one party for the benefit of another without the permission of the submitter. It thus provides

pioneering animal drug manufacturers with a reasonable expectation that their research and

development investments will not inure to the benefit of their competitors. See Tri-Bio Labs., Inc.

v. United States, 836 F.2d 135, 140-41 (3d Cir. 1987). The regulation does not, however, require

or even invite the FDA to adjudicate ownership disputes between competitors, as A.L. seems to

suggest.

The evidence presented to the district court clearly indicates that the FDA did not violate the

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terms of section 514.1(a). In its motion for summary judgment, the FDA alleged, and A.L. did not

dispute, that the safety data was submitted to the FDA by AHI along with a list of the study's

sponsors, which included Philips Roxane. In other words, "the person who submitted" the data to

the FDA "authorized" Philips Roxane's use. 21 C.F.R. § 514.1(a). Consequently, there was "no

genuine issue asto any materialfact," Fed. R. Civ. P. 56(c); and the agency was entitled to summary

judgment on that claim. Whether AHI erred by including Philips Roxane on the list of study sponsors

or, as A.L. argued to the district court, Philips Roxane had an obligation arising from an

understanding with an A.L. affiliate not to make use ofthe data, are issuesthat are simply not relevant

to the question of whether the FDA failed to abide by its regulation.

Even if the agency had violated its regulation when it approved Philip Roxane's application,

A.L.'s proposed remedy of vacatur and remand would be inappropriate in light of Philips Roxane's

replacement of the reference to MF 3578 in its application with a reference to the identical data in a

different master file. A.L. attempts to analogize this case to instances in which we have found an

agency action invalid due to procedural error and ordered the agency to repeat its process in

accordance with law. The cases it cites are distinguishable, however, by virtue of the fact that the

agencies involved had failed to take any corrective action. See, e.g., American Cyanamid Co. v.

FDA, 606 F.2d 1307, 1323-24 (D.C. Cir. 1979) (reversing FDA order when agency failed to grant

appellant a statutorily mandated hearing); Panhandle Eastern Pipe Line Co. v. FERC, 613 F.2d

1120, 1134-36 (D.C. Cir. 1979) (setting aside FERC order when agency misinterpreted its

regulations); Way of Life Television Network, Inc. v. FCC, 593 F.2d 1356, 1358-59 (D.C. Cir. 1979)

(reversing FCC licensing decision when agency improperly failed to publish a required notice in the

Federal Register).

Because the FDA has now approved Philips Roxane's product on the basis of unquestionably

proper safety data, it is clear that were we to vacate the FDA's approval of the application and

remand, Philips Roxane would merely duplicate its amended NADA, which refers to the data in the

replacement master file, and the FDA would approve the application. We do not remand where

"[t]here is not the slightest uncertainty as to the outcome of a[n] [agency] proceeding...." NLRB v.

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Wyman-Gordon Co., 394 U.S. 759, 766-67 n.6 (1969); see also American Train Dispatchers Ass'n

v. ICC, 26 F.3d 1157, 1163 (D.C. Cir. 1994) ("A remand is unnecessary where, as here, the outcome

of a new administrative proceeding is preordained.").

A remand of the FDA's action in this circumstance would serve only one purpose: the

punishment of Philips Roxane. To the extent that a misstatement in Philips Roxane's application

harmed A.L. directly, the latter's proper recourse was in the civil suit that it has, in fact, prosecuted

and won. To the extent that the misrepresentation harmed the FDA's administrative process, the

agency has broad latitude to determine an appropriate response. It is well within the discretion of the

FDA to decide not to penalize the company by withdrawing its approval of NADA 128-550. See

ABF Freight System, Inc. v. NLRB, 114 S. Ct. 835, 839-40 (1994) (finding no abuse of discretion

when the NLRB relied on "other civil and criminal remedies" to punish victim of an unfair labor

practice for lying to the Board rather than denying him administrative relief).

B. Bioequivalency

A.L. also renews its challenge to the agency's finding of bioequivalency between Philips

Roxane's bacitracin zinc and the benchmark product. It relies on affidavits and letters of sixteen

veterinary medicine research scientists that it submitted to the FDA to support its initial citizen

petition. Each of these experts contended that the results of the Prescott Study do not establish

bioequivalency. A.L. maintains that the unanimous views of these experts conclusively establish that

the FDA acted arbitrarily and thus illegally when it refused to rescind its approval of the NADA.

The scientists advance two formidable criticisms of the Prescott Study and of its acceptance

by the FDA as proof of bioequivalency. First, a number of them contend that a test of the relative

effectiveness of two drugsfor the purpose offighting a disease cannot prove equivalent effectiveness

for the purpose of promoting growth and feed efficiency. Second, A.L.'s experts questioned whether

the Prescott Study proved even that the drugs were equivalent for the purpose of fighting necrotic

enteritis, because the two drugs were tested at a single dosage. To reach such a conclusion, they

argue, different dosages would have to be tested and dose-response curves for the two products

constructed and compared. Without dose-response curves constructed from multiple data points,

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they believe, there is no way to rule out the possibility that one of the drugs barely reached

effectiveness at the dosage tested while the other would have been effective against the disease at a

fraction of the dose.

In denying A.L.'s first citizen petition, the FDA defended its reliance on Prescott's disease

study to establish bioequivalence by pointing out that because it is not possible to measure bacitracin

zinc levels in blood, this commonly used method for establishing bioequivalency was not available.

In addition, it noted it "d[id] not believe that it [was] necessary to test different levels of the drugs

and compare dose- response curves" in order to show "that the biological activity of the two drugs

against a known disease organism was not significantly different." 1982 Petition Denial at 2. On

appeal, the agency maintains that its scientific determinations were supported by the administrative

record. It specifically refers to its internal scientific evaluations and an affidavit provided by Dr.

Prescott stating his belief that, given certain assumptions, the two drugs "could be presumed to be

bioequivalent in clinical use...." Affidavit of John Prescott, Dec. 10, 1982, reprinted in J.A. at 106-

07.

As the FDA stresses, courts give a high level of deference to an agency's evaluations of

scientific data within its area of expertise. See, e.g., Schering Corp. v. FDA, 51 F.3d 390, 399 (3d

Cir. 1995) (FDA's "judgments asto what isrequired to ascertain the safety and efficacy of drugsfalls

squarely within the ambit of the FDA's expertise and merit deference from us."); International

Fabricare Inst. v. EPA, 972 F.2d 384, 389 (D.C. Cir. 1992) (rationale for deference "particularly

strong" when agencyevaluatesscientific evidencewithin itstechnical expertise). In addition, we must

defer to an agency'sinterpretation ofits own regulations "unlessit is plainlyerroneous or inconsistent

with the regulation," K N Energy, Inc. v. FERC, 968 F.2d 1295, 1299 (D.C. Cir. 1992) (quoting

United States v. Larionoff, 431 U.S. 864, 872 (1977)), regardless of whether interpreting the

regulation requires an agency'stechnical expertise. As an FDA regulation not challenged here permits

Philips Roxane to prove effectiveness by establishing bioequivalency but does not explicitly define

that term, 46 Fed. Reg. 37,043, 37,044, the agency has broad latitude in interpreting the standard.

Deferring to an agency's exercise of its discretion, however, is not tantamount to abdicating

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the judiciary'sresponsibility under the Administrative Procedure Act to set aside agency actionsthat

are "arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law." 5 U.S.C.

§ 706(2)(A) (1994). To enable us to fulfill our duty, "an agency must cogently explain why it has

exercised its discretion in a given manner," Motor Vehicle Mfr's Ass'n of the United States, Inc. v.

State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 48 (1983); and that explanation must be "sufficient to

enable us to conclude that the [agency's action] was the product of reasoned decisionmaking." Id.

at 52. Based on the record before us, we are unable to say that it was.

Of the two principal arguments advanced in A.L.'s affidavits as to why the study could not

prove bioequivalency, we are able to discern a reasoned response to onlyone. As the FDA explained,

because it had already determined that Philips Roxane's bacitracin zinc was "identical" to that in the

benchmark drug, the company was entitled to substitute proof of bioequivalency for proof of

effectiveness. See 46 Fed. Reg. at 37,044 (establishing rule that "approval for identical products in

poultry need not include certain types of efficacy data" normally required); 1982 Petition Denial at

1 (Philips Roxane and benchmark products "are considered "identical' "). Therefore, the purpose of

the Prescott Study was not to prove the effectiveness of Philips Roxane's products but, rather, to

determine whether they were bioequivalent with the benchmark drug. See 1982 Petition Denial at

2.

As we understand it, the FDA requires companies like Philips Roxane to submit

bioequivalency data not to determine whether the new drug contains the ingredients necessary to

promote growth and improve feed efficiency, because that has already been established; instead, it

seeksto determine whether the drug's deliverymechanismoperatessimilarlyto that ofthe benchmark

product. In this case, the FDA's scientists believed that "the expected differences [between the

performance of drugs in the necrotic enteritis study] ... are much greater than those for growth

experiments," Memorandum of Thomas V. Raines, D.V.M., Aug. 25, 1981, reprinted in J.A. at 37;

thus, a comparison of the drugs' abilities to fight disease was perhaps even a better measure of the

similarities of their delivery mechanisms than a direct comparison of the drugs' effects on growth

promotion. This position reflects a scientific determination within the scope of the FDA's expertise,

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to which we defer.

The agency, however, has provided no similarlyreasoned explanation ofwhyit disagrees with

A.L.'s experts' criticism that a single-dosage test cannot prove bioequivalency. Those scientists

charged, in effect, that the two drugs could have had an identical effect on necrotic enteritis during

the Prescott Study even if one delivered twice as much of the active ingredient or delivered it twice

as rapidly. Whether this criticism is relevant depends on what characteristics the two drugs must

share in order to be deemed bioequivalent. The FDA correctly defines the term "bioequivalence" in

the human drug context to mean

the absence of a significant difference in the rate and extent to which the active

ingredient or active moiety in pharmaceutical equivalents or pharmaceutical

alternatives becomes available at the site of drug action when administered at the

same molar dose under similar conditions in an appropriately designed study.

21 C.F.R. § 320.1(e) (1994); compare 21 U.S.C. § 355(j)(7)(B) (1988) (similar definition in human

drug portion of FDCA). The agency has not defined the term, by regulation, in the animal drug

context.

It is doubtful that the Prescott Study could meet the human drug bioequivalency standard

because, as A.L.'s experts note, comparisons of the rate and extent to which two drugs are delivered

to the site of drug action cannot be drawn from evaluations of the effects of a single dosage, at least

when it is not possible to measure the level of the drug in the bloodstream over time. There may be

more than one reasonable definition of bioequivalency, however; and the agency is entitled to latitude

in its construction of the term. But on the evidence before us, we cannot say that the FDA has

provided an adequate explanation for its conclusion that the Prescott Study demonstrated the

bioequivalency of the Philips Roxane and International Minerals bacitracin zinc products.

The FDA has made no attempt to "cogently explain," State Farm, 463 U.S. at 48, why A.L.

is mistaken when it contends that a single-dosage study unaccompanied by blood level comparisons

cannot prove bioequivalency. Neither its conclusory response to A.L. that it "does not believe that

it is necessary to test different levels of the drugs and compare dose-response curves," 1982 Petition

Denial at 2, nor its reminders that its scientific determinations are entitled to deference are sufficient

to enable us to reach the independent conclusion that its decision was the "product of reasoned

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decisionmaking." State Farm, 463 U.S. at 52. Accordingly, the district court erred by granting the

FDA's motion for summary judgment. We remand the issue so that the FDA may explain what

bioequivalency entailsin the animal drug context and how the Prescott Study satisfied that standard.

Although, on this record, we are unable to conclude that the FDA's approval of Philips

Roxane's application was not arbitrary and capricious, we are not required to vacate the approval.

See Checkosky v. SEC, 23 F.3d 452, 462-66 & App. (D.C. Cir. 1994) (Silberman, J.) (failure to

provide satisfactory explanation does not necessarilymean that agency has acted illegally; therefore,

court has discretion not to vacate agency action pending agency's elaboration of its reasoning);

Allied-Signal, Inc. v. NRC, 988 F.2d 146, 151 (D.C. Cir. 1993) (remanding rule to agency without

vacating "to develop a reasoned" explanation for its action). In deciding whether to vacate an

agency's decision pending further explanation, we consider "the seriousness ofthe order's deficiencies

(and thus the extent of doubt whether the agency chose correctly) and the disruptive consequences

of an interim change that may itself be changed." International Union, United Mine Workers of Am.

v. Federal Mine Safety and Health Admin., 920 F.2d 960, 967 (D.C. Cir. 1990).

In this case, the FDA may well be able to explain why it reasonably determined that the

Prescott Study demonstrated bioequivalency. In addition, vacating the rule approving the NADA

would prove disruptive to Philips Roxane, which hasrelied on it in good faith for over thirteen years.

By the same token, nothing in the record suggests that significant harm would result from allowing

the approval to remain in effect pending the agency's further explanation. Cf. Maryland People's

Counsel v. FERC, 768 F.2d 450, 455 (D.C. Cir. 1985) (declining to vacate agency order due to

expire soon where impact on petitioners and others similarly situated "is not likely to be especially

severe"). Therefore, we will leave the rule in place for a period of 90 days following the issuance of

this opinion. If, by the end of that period, the FDA has failed to provide an adequate justification for

its conclusion that the two drugs are bioequivalent, the rule approving Philips Roxane's application

will be vacated automatically as of the end of the 90th day.

III. CONCLUSION

For the reasons stated above, we set aside the district court's grant ofsummary judgment for

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the FDA and remand the case to the court with instructions to return the matter of NADA 128-550

to theFDAfor either reconsideration or an adequate explanation ofits determination that the Prescott

Study established bioequivalency.

So ordered.

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