202 F.3d 331 (D.C. Cir. 2000)
Washington Legal Foundation, Appelleev.Jane E. Henney,  Commissioner, Food and Drug Administration, and Donna E.  Shalala, Secretary, U.S. Department of Health and Human Services, Appellants
No. 99-5304
United States Court of Appeals FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued January 10, 2000Decided February 11, 2000

Appeal from the United States District Court for the District of Columbia(No. 94cv01306)
William B. Schultz, Deputy Assistant Attorney General,  United States Department of Justice, argued the cause for  appellants.  With him on the briefs were David W. Ogden,  Acting Assistant Attorney General, Douglas N. Letter and Michael S. Raab, Attorneys, Wilma A. Lewis, United States  Attorney, Eric M. Blumberg, Deputy Chief Counsel for Litigation, Food and Drug Administration, and Annamarie  Kempic, Associate Chief Counsel for Enforcement.
Bert W. Rein argued the cause for appellee.  With him on  the brief were Daniel J. Popeo, Richard A. Samp, Andrew S.  Krulwich, Thomas W. Queen, Daniel E. Troy, and Michael  L. Sturm.
Matthew Van Hook, Peter Barton Hutt, Bruce N. Kuhlik,  and Michael S. Labson were on the brief for amicus curiae  Pharmaceutical Research and Manufacturers of America.
Arthur B. Spitzer and Daniel I. Prywes were on the brief  for amicus curiae American Civil Liberties Union of the  National Capital Area.
Before:  Silberman, Williams, and Tatel, Circuit Judges.
Opinion for the Court filed by Circuit Judge Silberman.
Silberman, Circuit Judge:


1
The government appeals a district court decision holding that the Food and Drug Administration Modernization Act of 1997, which establishes procedures by which drug and medical device manufacturers may  disseminate information about "off-label" uses for their products, violates the First Amendment.  In light of the government's appellate position that the statute does not provide it  with independent authority to proscribe speech, we dismiss  the appeal and vacate the district court's injunction.


2
* * * *


3
To secure Food and Drug Administration (FDA) approval  for a drug or medical device,1 a manufacturer must demonstrate that its product is safe and effective for each of its  intended uses.  See 21 U.S.C. § 355(d);  id. at § 360e(e)(1)(A).It will often be discovered after initial FDA approval, however, that a drug has uses other than those for which it was approved.  These so-called "off-label uses" are subject to  asymmetrical--if not necessarily inconsistent--regulatory treatment.  On the one hand, it is unlawful for a manufacturer to  introduce a drug into interstate commerce with an intent that  it be used for an off-label purpose, see id. at § 331(d), and a  manufacturer illegally "misbrands" a drug if the drug's labeling includes information about its unapproveduses, see id. at  § 331(a);  id at § 352(a);  cf. Kordel v. United States, 335 U.S.  345, 348-50 (1948) (affirming broad definition of "labeling"  under the Food, Drug, and Cosmetic Act).  On the other  hand, neither Congress nor the FDA has attempted to regulate the off-label use of drugs by doctors and consumers.  A  physician may prescribe a legal drug to serve any purpose  that he or she deems appropriate, regardless of whether the  drug has been approved for that use by the FDA.  See, e.g.,  Citizen Petition Regarding the Food and Drug Administration's Policy on Promotion of Unapproved Drugs and Devices;  Request for Comments, 59 Fed. Reg. 59,820, 59,821  (1994).  Although the parties have differing views about the  health risks and benefits of off-label uses, it is undisputed  that the prescription of drugs for unapproved uses is commonplace in modern medical practice and ubiquitous in certain specialties.  See, e.g., James M. Beck & Elizabeth D.  Azari, FDA, Off-Label Use, and Informed Consent:  Debunking Myths and Misconceptions, 53 Food & Drug L.J. 71, 80  (1998).


4
While a manufacturer's direct advertising or explicit promotion of a product's off-label uses is likely to provoke an  FDA misbranding or "intended use" enforcement action,  manufacturers have sought to employ more indirect methods  of informing physicians about their products' off-label uses. This case concerns the FDA's and Congress' attempts to  regulate two of these promotional strategies:  manufacturer  dissemination to physicians of independent medical and scientific publications concerning the off-label uses of their products, and manufacturer support for Continuing Medical Education (CME) programs for doctors that focus on off-label  uses.  The FDA's examination of these practices led to  publication of an agency enforcement policy set forth in three guidance documents.  Two of these documents limited the  circumstances under which manufacturers could permissibly  distribute "enduring materials"--i.e., journal article reprints  and textbooks--to physicians.  See Guidance to Industry on  Dissemination of Reprints of Certain Published, Original  Data and Guidance for Industry Funded Dissemination of  Reference Texts, 61 Fed. Reg. 52,800 (1996) ("Enduring Materials Guidances").2  The third guidance document, concerning  manufacturer involvement in CME programs (the "CME  Guidance"), set forth twelve factors that the FDA will consider in determining whether a program is independent of  manufacturer influence.  See Guidance for Industry:  Industry-Supported Scientific and Educational Activities, 62 Fed.  Reg. 64,093, 64,096-99 (1997).


5
Washington Legal Foundation (WLF) brought this action  asserting that the policies articulated in the Guidance Documents violated the First Amendment right of its physician  members to receive information about off-label uses from  manufacturers.3  Cf. Virginia State Bd. of Pharmacy v. Virginia Citizens Consumer Council, Inc., 425 U.S. 748, 756-57  (1976) (First Amendment protections extend both to distribution and receipt of commercialspeech).  The district court, in  its decision granting summary judgment, began its discussion of WLF's constitutional claim by classifying the speech being  regulated.  Rejecting both the WLF's contention that the  policies restricted fully-protected scientific speech and the  FDA's argument that the speech was constitutionally unprotected because it "proposed an illegal transaction," the court  determined that the Guidance Documents regulated commercial speech.  See Washington Legal Foundation v. Friedman,  13 F .Supp.2d 51, 62-65 (D.D.C. 1998) (WLF I).  It then  applied the three-part test set forth in Central Hudson Gas &  Elec. Corp. v. Public Serv. Comm'n, 447 U.S. 557 (1980), to  determine whether the policies' restrictions on commercial  speech exceeded constitutional limits.  It concluded that the  Guidance Documents satisfied the first and second parts of  Central Hudson, since they directly advanced the government's substantial interest in encouraging manufacturers to  seek FDA approval for off-label uses.  They fell short of  satisfying the final part of the Central Hudson test, however,  because the policies restricted considerably more speech than  necessary to encourage manufacturers to achieve this objective.  See WLF I, 13 F. Supp.2d at 65-74.  Holding that the  Enduring Materials and CME   Guidances violated the First  Amendment, the court enjoined the FDA from prohibiting  manufacturers' dissemination of enduring materials "regardless of whether such [materials] include[ ] a significant or  exclusive focus" on off-label uses, and from proscribing manufacturers from suggesting content to CME program providers.  Id. at 74-75.


6
Shortly after the district court issued its injunction, the  Food and Drug Administration (FDA) Modernization Act of  1997, Pub. L. No. 105-115, 111 Stat. 2296 (FDAMA or the  Act), became effective.  The Act includes provisions concerning manufacturer distribution of enduring materials on off label uses that supersede4 the Enduring Materials Guidances found unconstitutional in WLF I.  See 21 U.S.C. §§ 360aaa et  seq.  It specifically authorizes a manufacturer to disseminate  "written information concerning the safety, effectiveness, or  benefit of a use not described in the approved labeling of a  drug or device," 21 U.S.C. § 360aaa(a), if it complies with  several requirements:  the manufacturer must submit an application to the FDA seeking approval of the drug for the off label use;  the manufacturer must provide the materials to the  FDA prior to dissemination;  the materials themselves must  be in unabridged form;  and the manufacturer must include  disclosures that the materials pertain to an unapproved use of  the drug, and, if the FDA deems it appropriate, "additional  objective and scientifically sound information ... necessary to  provide objectivity and balance."  See 21 U.S.C.  § 360aaa(b)(1)-(6);  id. at 360aaa(c);  id. at 360aaa-1.  Importantly, the Act amends the Food, Drug, and Cosmetic Act to  prohibit "[t]he dissemination of information in violation" of  these provisions.  21 U.S.C. § 331(z);  see also id. at  § 360aaa-4(b)(1) (emphasis added).


7
After the Act became effective, questions arose concerning  the scope of the district court's decision and injunction in  WLF I.  The government asserted that the district court's  ruling applied only to the Guidance Documents, two of which  had been superseded by the Act, and asked that the district  court confine the application of its injunction accordingly. The court denied the FDA's motion, noting that its "decision  and injunction must be read to apply to the underlying  policies of theFDA, and not merely to the express provisions  of the Guidance Documents," Washington Legal Foundation  v. Friedman, 36 F.Supp.2d 16, 18 (D.D.C. 1999) (WLF II),  and requested supplemental briefing on the constitutionality  of the Act's provisions addressing manufacturer promotion of  off-label uses.  In a subsequent opinion, the district court  held that those provisions, like the Enduring Materials Guid-ances that preceded them, violated the First Amendment. See Washington Legal Foundation v. Henney, 56 F.Supp.2d 81 (D.D.C. 1999) (WLF III).  The FDA appealed, contending  that the district court erred in concluding that the FDAMA  and the CME Guidance are unconstitutional.


8
The stage therefore appeared set for us to consider a  difficult constitutional question of considerable practical importance.  However, as a result of the government's clarification at oral argument, the dispute between the parties has  disappeared before our eyes.  The parties' briefs were quite  confusing as to the meaning of the Act and the CME Guidance, perhaps because both provisions became effective during the later stages of the litigation in the district court. While WLF clearly understood these provisions as independently banning both manufacturer dissemination of enduring  materials on off-label uses and support for CME conferences,  see, e.g., Appellee's Br. at 1, 12-13, 20, 33, the FDA's view of  the Act and the CME Guidance was somewhat unclear:  At  times the FDA appeared to share WLF's assessment that  these provisions provide legal authorization to restrict manufacturer speech, but more frequently the FDA asserted that  they established nothing more than a "safe harbor" ensuring  that certain forms of conduct would not be used against  manufacturers in misbranding and "intended use" enforcement actions based on pre-existing legislative authority. Compare Appellant's Br. at 34-35 (safe harbor) with id. at  46-47, 51 (describing provisions as restricting speech, and  noting that "enforcement of the FDCA's misbranding provision ... is a wholly inadequate substitute for the FDAMA").In response to questioning at oral argument, the government  definitively stated that it subscribed to the "safe harbor"  interpretation and further explained that, in its view, neither  the FDAMA nor the CME Guidance independently authorizes the FDA to prohibit or to sanction speech.5  When we pressed government counsel about the significance of 21  U.S.C. § 331(z)--which specifically prohibits "the dissemination of information in violation of section 360aaa"--he explained that this provision provides that a manufacturer who  disregards section 360aaa's conditions cannot avail itself of  the FDAMA safe harbor, and might be liable in some fashion  if it breached an agreement with the Secretary pursuant to  that section.  See Tr. at 34.  Were a pharmaceutical company  to send out reprints of an article devoted to its drug's off label uses to thousands of physicians tomorrow, the government agreed--indeed stipulated-that the agency would draw  no independent prosecutorial authority from FDAMA to buttress any enforcement proceeding.  See Tr. at 60--61.  And  the FDA offers a similar view of the CME Guidance:  If a  drug manufacturer wishes to suggest content to a CME  program provider in a manner that runs afoul of all the  Guidance's twelve "factors" that, by itself, is not a violation of  law.  See Tr. at 73-74.  Although the FDA retains the  prerogative to use both types of arguably promotional conduct as evidence in a misbranding or "intended use" enforcement action, cf. Action on Smoking and Health v. Harris, 655  F.2d 236, 239 (D.C. Cir. 1980) (observing that "it is well  established that the 'intended use' of a product, within the  meaning of the [Food, Drug, and Cosmetic] Act, is determined from its label, accompanying labeling, promotional  claims, advertising, and any other relevant source" (internal  citations omitted)), the agency insists that nothing in either of  the provisions challenged in this case provides the FDA with  independent authority to regulate manufacturer speech.


9
WLF responded that in light of the government's position  as refined and explained at oral argument it no longer has a  constitutional objection to the Act or the CME Guidance,6 see  Tr. at 52, 66-68, 69--a response that, it would seem, eliminates  entirely the only issues in dispute between the parties in this  case.  WLF apparently believes we should nevertheless affirm the district court.  It is a well-recognized principle that a  case will not become moot merely because a defendant agrees  voluntarily to cease engaging in the challenged conduct, as  there remains a risk that the defendant will merely resume  the challenged conduct after the case is dismissed.  See, e.g.,  United States v. W. T. Grant Co., 345 U.S. 629, 632 (1953).Voluntary cessation of challenged conduct will only moot a  case if "subsequent events made it absolutely clear that the  allegedly wrongful behavior could not reasonably be expected  to recur."  Friends of the Earth, Inc. v. Laidlaw Environmental Servs. (TOC), Inc., 120 S.Ct. 693, 708, 145 L.Ed.2d 610 (2000) (quoting United States v. Concentrated Phosphate Export Assn., Inc., 393 U.S. 199, 203 (1968)).  Relying  on this principle, and apparently concerned that the FDA will  prosecute manufacturers for violating a normative standard  set forth in the Act or CME Guidance notwithstanding the  agency's concession in this case that it has no authority to do  so, WLF indicates that we should still reach the merits of the  district court's decision and injunction.


10
We think that WLF misapprehends the nature and significance of the FDA's concessions, which do not in our view  implicate principles of mootness at all.  This is not an instance of "voluntary cessation," since WLF has not alleged  that FDA engaged in any conduct pursuant to the challenged  statute and guidance document.  The relevant question before us therefore is not whether certain enforcement activities  conducted under these provisions were unconstitutional (since  there were no such activities alleged), but instead whether the  statute and guidance document facially violate the First Amendment.  Since both parties now agree that they do not,  there is no constitutional controversy between the parties  that remains to be resolved;  we do not think it at all  appropriate to rule on the constitutionality of a hypothetical  interpretation of a statute, see Aetna Life Ins. Co. v. Haworth, 300 U.S. 227, 240-41 (1937) (distinguishing a justiciable  controversy from "a difference or dispute of a hypothetical or  abstract character"), which is what WLF in effect requests by  suggesting that we "reach the merits" of the district court's  decision.  The government has announced here nothing less  than an official interpretation of the FDAMA which the  agency may not change unless it provides a reasoned explanation for doing so.  See Amax Land Co. v. Quarterman, 181  F.3d 1356, 1365 & n.6 (D.C. Cir. 1999).  It goes without  saying that an attempt to evade judicial review in this case  would hardly be a legitimate basis.  Cf. AT & T v. FCC, 978  F.2d 727, 731-32 (1993).


11
Accordingly, we dismiss the FDA's appeal and vacate the  district court's decisions and injunctions insofar as they declare the FDAMA and the CME Guidance unconstitutional.7


12
So ordered.



Notes:


1
 For brevity's sake we use the term "drugs" to encompass  drugs and medical devices, both of which are regulated under the  statute and guidance document at issue here.


2
 These Guidances provided that, while a manufacturerdistributed article could reference a product's off-label use, "the  principal subject of the article should be the use[ ] ... that has been  approved by FDA," 61 Fed. Reg. at 52,801;  it also stated that the  manufacturer should indicate clearly to the recipient that the article  discusses "information that is different from approved labeling."Id.  The Guidances included similar provisions limiting the dissemination of medical textbooks where the textbook contains content too  extensively devoted to off-label uses.  See id.


3
 WLF's original complaint, filed before the FDA published the  Guidances, was based on a series of FDA actions taken against  manufacturers for their dissemination of off-label information that  WLF asserted constituted final agency policy.  See Washington  Legal Foundation v. Kessler, 880 F.Supp. 26 (D.D.C. 1995).  The  Guidance Documents were published during the course of the  litigation.


4
 We emphasize that the FDA unequivocally stipulated in its  briefs and at oral argument that the Act and its implementing  regulations supersede, rather than supplement, the Enduring Material Guidances.  And even if they were not superseded, they would  be unenforceable, since the FDA does not challenge on appeal the district court's decision and injunction insofar as they pertain to the  Enduring Material Guidances.  See WLF I, 13 F.Supp.2d at 74.


5
 The government's position, articulated and repeated several  times during oral argument, is most succinctly presented by the  following colloquy:
THE COURT: ....  I thought your whole explanation of thisstatute and the guidance was that they have established aprocedure for manufacturers who distribute certain materials regarding off-label uses in such a way that they will not beused as evidence against them in a prosecution under them is branding provisions.  I thought that's what this was about.And that I thought that any manufacturer could distributeanything they wanted, if they wanted to take a chance ofending up a defendant in a mislabeling case.  Isn't that right?
COUNSEL:  That's all correct.  That's all correct.
THE COURT:  That's all correct.
COUNSEL:  Yes.
Tr. at 31-32.


6
 A manufacturer, of course, may still argue that the FDA's use  of a manufacturer's promotion of off-label uses as evidence in a  particular enforcement action violates the First Amendment.


7
 In disposing of the case in this manner, we certainly do not  criticize the reasoning or conclusions of the district court.  As we  have made clear, we do not reach the merits of the district court's  First Amendment holdings and part of its injunction still stands.


