Prohibition Juice Co. v. FDA ( 2022 )


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  •  United States Court of Appeals
    FOR THE DISTRICT OF COLUMBIA CIRCUIT
    Argued April 21, 2022                   Decided July 26, 2022
    No. 21-1201
    PROHIBITION JUICE CO.,
    PETITIONER
    v.
    UNITED STATES FOOD AND DRUG ADMINISTRATION,
    RESPONDENT
    Consolidated with 21-1203, 21-1205, 21-1207
    On Petitions for Review of an Order
    of the Food & Drug Administration
    Jerad Wayne Najvar argued the cause and filed the briefs
    for petitioners.
    J. Gregory Troutman was on the brief for amici curiae 36
    National and State Electronic Nicotine Delivery System
    Product Advocacy Associations in support of petitioners.
    Scott P. Kennedy, Trial Attorney, U.S. Department of
    Justice, argued the cause for respondent. With him on the brief
    were Brian M. Boynton, Principal Deputy Assistant Attorney
    2
    General, and Hilary K. Perkins, Assistant Director. Courtney
    Dixon, Kathleen Gilchrist, Alisa B. Klein, Joshua M. Koppel,
    and Lindsey Powell, Attorneys, entered appearances.
    William B. Schultz and Andrew N. Goldfarb were on the
    brief for amici curiae Medical and Public Health Groups in
    support of respondent.
    Before: HENDERSON, PILLARD, and KATSAS, Circuit
    Judges.
    Opinion for the Court filed by Circuit Judge PILLARD.
    Concurring opinion filed by Circuit Judge KATSAS.
    PILLARD, Circuit Judge: More than 3.6 million young
    people in the United States reported using e-cigarettes in 2020,
    including nearly one in five high school students. That makes
    e-cigarettes “the most widely used tobacco product among
    youth by far.” FDA, Technical Project Lead (TPL) Review of
    PMTAs (2021) (FDA Technical Review), at 6. The public
    health consequences are dire: Tobacco is quickly and
    powerfully addicting, and e-cigarettes can permanently
    damage developing adolescent brains, cause chronic lung
    diseases, and hook young users for life. Given the scale and
    severity of the problem, by 2018 the Surgeon General had
    already decried an “epidemic” of youth e-cigarette use. 1 And
    1
    Surgeon General of the United States Public Health Service,
    Surgeon General’s Advisory on E-cigarette Use Among Youth (Dec.
    2018), https://www.cdc.gov/tobacco/basic_information/e-cigarettes/
    surgeon-general-advisory/pdfs/surgeon-generals-advisory-on-e-
    cigarette-use-among-youth-2018-h.pdf       [https://perma.cc/3FPK-
    7MRL]; see also Scott Gottlieb, Statement from FDA Commissioner
    Scott Gottlieb, M.D., on New Steps to Address Epidemic of Youth E-
    3
    the FDA declared in 2021 that “preventing tobacco use
    initiation in young people is a central priority for protecting
    population health.” FDA Technical Review at 6.
    Flavored tobacco products lie at the heart of the problem.
    A vast body of scientific evidence shows that flavors encourage
    youth to try e-cigarettes and, together with the nicotine, keep
    them coming back. With names like Brain Freeze Caramel
    Cone, Crazy Bubble Grape, and Green Apple Gummy Guts,
    flavors play a “fundamental role” in driving youth interest in e-
    cigarette use. FDA Technical Review at 8. The FDA has
    concluded that the availability of flavored products “is one of
    the primary reasons for the popularity of [e-cigarettes] among
    youth.” Id. at 6.
    Congress has called on the FDA to regulate e-cigarette
    products pursuant to the Family Smoking Prevention and
    Tobacco Control Act, Pub. L. No. 111-31, 
    123 Stat. 1776
    (2009) (Tobacco Control Act or Act). Under the Act,
    manufacturers must apply for FDA authorization to sell new
    tobacco products, which the FDA grants only if it determines
    that doing so would be “appropriate for the protection of the
    public health.” 21 U.S.C. § 387j(c)(2)(A). The agency makes
    that determination by weighing, on a population-wide basis,
    any benefits of such products against their harms. Id.
    § 387j(c)(4).
    Prohibition Juice makes flavored liquids containing
    nicotine derived from tobacco, which it sells for use in e-
    cigarettes, or Electronic Nicotine Delivery Systems (ENDS).
    cigarette Use (Sept. 11, 2018), https://www.fda.gov/news-
    events/press-announcements/statement-fda-commissioner-scott-
    gottlieb-md-new-steps-address-epidemic-youth-e-cigarette-use
    [https://perma.cc/RL2A-4Y8F].
    4
    Along with the three other e-liquid manufacturer petitioners,
    Prohibition applied in September 2020 for FDA authorization
    to market several flavors in a range of sizes. The FDA denied
    those applications a year later. 2 In view of flavored tobacco
    products’ serious, well-documented, and lasting risks to youth,
    the FDA requires applicants to present reliable evidence of
    robust public health benefits exceeding known risks. The
    manufacturers describe their products as a beneficial
    alternative to combustible cigarettes that offer comparative
    health benefits to existing smokers. Finding the manufacturers
    had presented insufficient evidence that their flavored products
    are more effective than unflavored products in helping adult
    cigarette smokers decrease or quit harmful tobacco uses, the
    FDA denied the applications.
    The manufacturers petition for review of those denials.
    They first argue that the FDA lacked statutory authority to
    require that parties establish that their flavored liquids carry
    greater public health benefits than unflavored liquids. They
    also challenge the application denials as arbitrary and
    capricious, asserting that the FDA (1) departed from an earlier
    guidance document, changing both the types of evidence the
    agency would accept and the substantive showing it expected
    parties to make; (2) underscored the potential importance of
    marketing plans including measures to limit youth access to
    their products but then failed to consider the plans petitioners
    submitted; and (3) overlooked various other aspects of the
    problem.
    2
    The FDA applied a common Technical Project Lead memorandum
    to the four manufacturers’ applications, and the record includes four
    copies, as sent to each of four petitioners. See J.A. 34-53, 819-38,
    1016-34, 1223-42.
    5
    We deny the petitions for review. The FDA plainly had
    statutory authority under the Tobacco Control Act to regulate
    as it did. As to the arbitrary and capricious challenges, we hold
    that the FDA did not change the evidentiary or substantive
    standard from its 2019 Guidance. We also hold that any error
    in the FDA’s failure to consider the marketing plans was
    harmless because the manufacturers failed to identify how
    individualized review of the plans they submitted could have
    made any difference. Finally, the FDA did not otherwise fail
    to consider important aspects of the problem. We accordingly
    deny the petitions for review.
    I. BACKGROUND
    A. Statutory Background
    In 2009, Congress enacted the Tobacco Control Act to
    regulate the sale of tobacco products. Pub. L. No. 111-31, 
    123 Stat. 1776
    . Congress concluded that the “use of tobacco
    products by the Nation’s children is a pediatric disease of
    considerable proportions that results in new generations of
    tobacco-dependent children and adults.” 
    Id.
     § 2, 123 Stat. at
    1777. We canvassed the history of the Tobacco Control Act in
    Nicopure Labs, LLC v. FDA, 
    944 F.3d 267
     (D.C. Cir. 2019),
    where we recounted that Congress acted based on extensive
    evidence that tobacco is widely used, highly addictive, and
    destructive of human health. See id. at 270-79. The enacting
    Congress knew that kids are key: The FDA had already shown
    that the vast majority of adults who smoke have their first
    cigarette before the age of 18, and that “[v]irtually all new users
    of tobacco products are under the minimum legal age to
    purchase such products.” Id. at 272 (quoting the Tobacco
    Control Act, Pub. L. No. 111-31, §§ 2(3), (4), 123 Stat. at 1777
    (alteration in original)). Businesses seeking to make a profit
    selling tobacco products know that, too, and face powerful
    6
    economic incentives to reach younger customers. A core
    objective of the Tobacco Control Act is to “ensure” tobacco
    products will not be “sold or accessible to underage
    purchasers.” Pub. L. No. 111-31, § 3(7), 123 Stat. at 1782.
    Under the Act, a “new tobacco product” may not be
    marketed in interstate commerce unless the manufacturer
    obtains premarket authorization from the FDA. 21 U.S.C.
    § 387j(a)(1)-(2). The FDA in turn “shall deny” an application
    to market a new tobacco product unless the agency finds “that
    permitting such tobacco product to be marketed would be
    appropriate for the protection of the public health.” Id.
    § 387j(c)(2). The statute explains how the FDA is to determine
    whether approving a product is, on balance, appropriate for the
    protection of public health:
    For purposes of this section, the finding as to whether
    the marketing of a tobacco product for which an
    application has been submitted is appropriate for the
    protection of the public health shall be determined
    with respect to the risks and benefits to the
    population as a whole, including users and nonusers
    of the tobacco product, and taking into account—
    (A) the increased or decreased likelihood that
    existing users of tobacco products will stop
    using such products; and
    (B) the increased or decreased likelihood that those
    who do not use tobacco products will start
    using such products.
    Id. § 387j(c)(4)(A)-(B).
    7
    That statutory directive reflects the fact that tobacco is
    highly addictive and generally harmful to human health. Proof
    that a new tobacco product has public health benefit thus
    depends on favorable substitution effects, such as evidence that
    the new product is less harmful to existing users than current
    products, and that it either draws existing users away from the
    more harmful tobacco products or helps them to quit altogether.
    Any such benefit must be shown to offset the product’s public
    health harms to new users, including youth.
    The statute also directs manufacturers to include in their
    applications “full reports of all information . . . concerning
    investigations which have been made to show the health risks
    of such tobacco product and whether such tobacco product
    presents less risk than other tobacco products.”            Id.
    § 387j(b)(1)(A). The Act grandfathered tobacco products on
    the market as of February 15, 2007, excusing them from the
    premarket authorization requirement. Id. § 387j(a)(1). But no
    product brought to market after that date may lawfully be sold
    unless and until it receives FDA premarket authorization.
    B. Regulatory Background
    Electronic cigarettes subject to the Tobacco Control Act
    deliver nicotine to their users by vaporizing a liquid derived
    from tobacco. See Nicopure Labs, 944 F.3d at 270, 272. These
    devices are either disposable (closed) or refillable (open).
    Open systems are refilled either by inserting a pod or cartridge
    containing the liquid into the device or by manually pouring in
    the liquid. For current purposes, the liquids inside those
    devices are treated as either non-flavored, meaning they taste
    like tobacco, or as flavored because they carry a distinctive,
    often sweet, flavoring. Flavored liquids are the subject of this
    challenge. The FDA is separately addressing applications for
    menthol-flavored devices, see FDA Technical Review at 3 n.ii,
    8
    and is re-evaluating whether it mistakenly included some
    tobacco- and menthol-flavored products in the denial order
    challenged here, see FDA Br. 16 n.6. (This opinion does not
    address those products.)
    A hallmark of flavored liquids is their disproportionate
    appeal to children. The FDA cited clear scientific consensus
    that such products hold “extraordinary popularity” among
    youth. FDA, Enforcement Priorities for Electronic Nicotine
    Delivery Systems (ENDS) and Other Deemed Products on the
    Market Without Premarket Authorization (Revised) (2020)
    (2020 Guidance). One study found that 93.2% of youth e-
    cigarette users and 83.7% of young adult users (ages 18-24)
    reported their first e-cigarette was flavored, and 84.7% of high
    school e-cigarette users reported using a flavored product in
    2020. FDA Technical Review at 6. The agency also surveyed
    compelling evidence that youth are more likely than adults to
    use flavored products. Id. It accordingly concluded that, for
    flavored products, “the risk of youth initiation and use is
    substantial.” Id. at 10.
    In view of flavored tobacco products’ appeal to young
    people, it is especially challenging for marketers to make a case
    that those products are appropriate for the protection of public
    health. Applicants seeking to market e-cigarettes have
    generally sought to show that their products cause users of
    existing, less safe tobacco products to transition to safer use
    patterns without enticing new users, especially children. That
    is, again, because the FDA may approve a new product only if
    the applicant succeeds in showing that its benefits to the
    population as a whole outweigh its risks.
    In 2016, the FDA promulgated a “deeming rule”
    designating e-cigarettes and their component e-liquids as “new
    9
    tobacco products” under the Act. 3 That means Prohibition
    Juice and other e-liquid manufacturers may not lawfully market
    their products without FDA approval. We rejected a challenge
    to that deeming rule in Nicopure Labs, sustaining both the
    Tobacco Control Act and its application to e-cigarettes. 944
    F.3d at 272.
    As a matter of enforcement discretion, however, the FDA
    announced it would not enforce the Act against new (post-
    2007) products for staggered two-to-three-year periods. See
    Deeming Rule, 81 Fed. Reg. at 28,977-78. Following a further
    FDA extension in 2017 of up to six years, a suit by the
    American Academy of Pediatrics garnered a court-ordered
    deadline, which in turn was adjusted due to the COVID-19
    pandemic. See Am. Acad. of Pediatrics v. FDA, 
    399 F. Supp. 3d 479
    , 487 (D. Md. 2019), appeal dismissed sub nom. In re
    Cigar Ass’n of Am., 812 F. App’x 128 (4th Cir. 2020). The
    deadline for manufacturers to submit their marketing
    applications ultimately settled on September 9, 2020. See
    Breeze Smoke, LLC v. FDA, 
    18 F.4th 499
    , 504 (6th Cir. 2021).
    Meanwhile, a wave of new e-cigarette products flooded the
    market without scientific review or premarket authorization,
    causing e-cigarette use to hit the highest levels ever seen. See
    2020 Guidance at 6-9.
    Central to the manufacturers’ claims is a nonbinding
    guidance document the FDA issued in 2019 to help
    manufacturers prepare applications ahead of the deadline.
    FDA, Premarket Tobacco Product Applications for Electronic
    3
    See Deeming Tobacco Products to Be Subject to the Federal Food,
    Drug, and Cosmetic Act, as Amended by the Family Smoking
    Prevention and Tobacco Control Act; Restrictions on the Sale and
    Distribution of Tobacco Products and Required Warning Statements
    for Tobacco Products (Deeming Rule), 
    81 Fed. Reg. 28,974
     (May
    10, 2016).
    10
    Nicotine Delivery Systems: Guidance for Industry (June 2019)
    (2019 Guidance). Prohibition Juice highlights two pieces of
    that guidance. First, it points to the FDA’s discussion of the
    types of evidence that applicants should consider submitting.
    2019 Guidance at 12-13. In relevant part, the agency wrote:
    Given the relatively new entrance of [e-cigarettes] on
    the U.S. market, FDA understands that limited data
    may exist from scientific studies and analyses. If an
    application includes, for example, information on
    other products (e.g., published literature, marketing
    information) with appropriate bridging studies, FDA
    intends to review that information to determine
    whether it is valid scientific evidence sufficient to
    demonstrate that the marketing of a product would
    be [appropriate for the protection of public health].
    Nonclinical studies alone are generally not sufficient
    to support a determination that permitting the
    marketing of a tobacco product would be appropriate
    for the protection of the public health. Nonetheless,
    in general, FDA does not expect that applicants will
    need to conduct long-term studies to support an
    application.
    2019 Guidance at 12-13 (footnote omitted).
    Second, the manufacturers focus on how the agency
    recommended that applicants compare their products to other
    tobacco products to help identify and account for their own
    product’s relative health risks. In a section titled “Comparison
    Products,” the agency wrote:
    As part of FDA’s consideration under 910(c)(4) of
    the FD&C Act of the risks and benefits of the
    marketing of the new tobacco product to the
    11
    population as a whole, including users and nonusers
    of tobacco products, FDA reviews the health risks
    associated with changes in tobacco product use
    behavior (e.g., initiation, switching, dual use,
    cessation) that are likely to occur with the marketing
    of the new tobacco product. We recommend an
    applicant compare the health risks of its product to
    both products within the same category and
    subcategory, as well as products in different
    categories as appropriate. . . . This comparative
    health risk data is an important part of the evaluation
    of the health effects of product switching. . . . For
    example, for [an application] for an e-liquid, FDA
    recommends the product’s health risks be compared
    to those health risks presented by other e-liquids used
    in a similar manner.
    2019 Guidance at 13-14.
    The FDA followed up with a 2020 guidance document
    setting out the agency’s enforcement priorities. FDA,
    Enforcement Priorities for Electronic Nicotine Delivery
    Systems (ENDS) and Other Deemed Products on the Market
    Without Premarket Authorization (Revised) (2020) (2020
    Guidance). The FDA issued that guidance after industry
    manufacturers, at FDA’s urging, had identified a variety of
    measures, including age verification, they said they would use
    to try to restrict minors’ access to their products. See 2020
    Guidance at 7. The 2020 Guidance emphasized that,
    notwithstanding such measures, youth e-cigarette use “has hit
    the highest levels ever recorded.” Id. at 8. With the rising wave
    of youth vaping, the “extraordinary popularity” of flavored
    products driving that rise, and industry’s measures proving
    insufficient to stem it, the FDA announced that flavored
    products would be an enforcement priority. Id. at 13, 18-21.
    12
    As a result, by the September 9, 2020, deadline for
    submitting applications, the FDA had publicly highlighted the
    particular dangers of flavored products and noted the types of
    rigorous scientific evidence it would accept in support of
    applications to market such products. The FDA received
    applications from more than five hundred companies, many
    submitted shortly in advance of that deadline, including those
    of the four petitioners here. Enforcement was suspended for an
    additional year following the deadline to allow the FDA time
    to review and act on the applications. See Deeming Rule, 81
    Fed. Reg. at 28,9778.
    C. Procedural History
    Prohibition Juice, ECig Charleston L.L.C., Cool Breeze
    L.L.C., and Jay Shore Liquids L.L.C. manufacture flavored e-
    liquid products. In September 2020, the manufacturers applied
    for approval to market a large set of variously flavored e-liquid
    products. A small sampling of the flavors the manufacturers
    seek to sell includes Prohibition Juice’s Boozehound, Sweet
    Thang, White Lightning, and Black Market (J.A. 3-24); Cool
    Breeze’s Awesome Sauce (Peach, Raspberry, Strawberry),
    Brain Freeze Caramel Cone, Buncha Crunch (Crunch Fruit
    Cereal), Crazy Bubble Grape, Giggle Juice, Jolly Apple, and
    Sugar Rush Peach Ring Candy (J.A. 472-807); ECig’s
    Cinnamon Pear, Banana Strawberry, Cloud Chaser, and
    Fireball Cinnamon (J.A. 986-1006); and Jay Shore’s Blueberry
    Dream Cake, Green Apple Gummy Guts, Pink-Burst, and
    Rootbeer Float (J.A. 1197-213).
    Each manufacturer submitted a marketing plan as part of
    its application. See J.A. 268-76 (Prohibition); J.A. 861-64
    (Cool Breeze); J.A. 1036-41 (ECig); J.A. 1264-77 (Jay Shore).
    The marketing plans described measures each manufacturer
    13
    was taking to limit youth access to their products. See Pet’rs
    Br. at 39. As examples, the manufacturers highlighted their use
    of age-verification “gating” on their websites (accepting any
    qualifying birthdate) and “dull, less vibrant colors” without
    “mascots and similar characters” on their labeling to avoid
    appealing to youth. Id. (internal quotation omitted). Other e-
    cigarette companies are developing novel technologies, such as
    requiring age verification assisted by facial recognition
    software to unlock their products, which they assert could
    prevent underage use. The FDA noted those developments and
    explained that it communicates with tobacco companies to
    keep abreast of measures that might better control youth access
    to their products. See Oral Argument Tr. at 31-32. Petitioners
    acknowledge that their marketing plans proposed no such novel
    controls. See Oral Argument Tr. at 12.
    In September 2021, the FDA denied petitioners’
    applications. It did so based on a common memorandum it
    issued to all four manufacturers setting out the analytic
    framework under which the agency assessed their applications.
    It also issued each manufacturer a separate denial letter and
    review memorandum.
    The FDA’s common memorandum began by surveying the
    well-known risks of flavored electronic nicotine delivery
    systems to youth. FDA Technical Review at 4-9. It noted the
    data showing dramatic and accelerating rates of youth use of e-
    cigarette products, notwithstanding the decrease in cigarette
    smoking by youth. Id. at 4-7. The memorandum also
    referenced evidence that flavors drive youth uptake, intensity
    of use, and addiction, and that flavored products appeal more
    to youth than they do to adults. Id. The FDA surveyed the
    substantial damage nicotine causes to the adolescent brain. Id.
    at 8-9. It emphasized that the youth preference for flavor
    remained “consistent” across different types of devices. Id. at
    14
    7. While there may be “variability” in the popularity of
    different device types among youth, young people consistently
    use whichever products will allow them to enjoy flavors that
    appeal to them—evidence the FDA described as “underscoring
    the fundamental role of flavor in driving appeal.” Id. at 7-8.
    Based on this evidence, the FDA concluded that flavored e-
    liquids “pose a significant risk to youth.” Id. at 9.
    The FDA then considered how best to weigh that known
    risk against potential benefits to adult smokers. It concluded
    that “any risks posed by a new product to youth would need to
    be overcome by a sufficient benefit to adult users, and as the
    known risks increase, so too does the burden of demonstrating
    a substantial enough benefit.” FDA Technical Review at 10.
    And because flavored products carry a “substantial” risk of
    youth initiation, the FDA determined that such products would
    be approved only if a manufacturer could show “that the
    significant risk to youth could be overcome by likely benefits
    substantial enough such that the net impact to public health
    would be positive.” Id. In sum, the FDA required that
    manufacturers produce evidence that is scientifically rigorous;
    compares flavored liquids to non-flavored liquids; and
    establishes that flavored products have substantial benefits
    over non-flavored ones to fully overcome flavored products’
    known risks.
    In separate denial orders to each manufacturer, the FDA
    explained how each had failed to make that showing. The FDA
    concluded that the manufacturers had not submitted rigorous
    evidence demonstrating benefits of their flavored products as
    compared to unflavored products—be that evidence from
    randomized controlled trials, longitudinal studies, or some
    other form of analysis. Without reliable, probative evidence of
    benefits outweighing the products’ known risks, the FDA
    denied the applications.
    15
    The FDA also declined to review the manufacturers’
    marketing plans, stating its rationale in a footnote:
    Limiting youth access and exposure to marketing is
    a critical aspect of product regulation. It is
    theoretically possible that significant mitigation
    efforts could adequately reduce youth access and
    appeal such that the risk for youth initiation would be
    reduced. However, to date, none of the [applications]
    that FDA has evaluated have proposed advertising
    and promotion restrictions that would decrease
    appeal to youth to a degree significant enough to
    address and counter-balance the substantial
    concerns, and supporting evidence, discussed above
    regarding youth use. Similarly, we are not aware of
    access restrictions that, to date, have been successful
    in sufficiently decreasing the ability of youth to
    obtain and use [e-cigarettes]. Accordingly, for the
    sake of efficiency, the evaluation of the marketing
    plans in applications will not occur at this stage of
    review, and we have not evaluated any marketing
    plans submitted with these applications.
    FDA Technical Review at 11 n.xix.
    The manufacturers timely petitioned this court for review,
    and we consolidated the cases.
    D. Decisions in Parallel Cases
    Under the Tobacco Control Act’s judicial review
    provision, a party subject to a marketing denial order may
    petition for review either in this court or in the circuit in which
    its principal place of business is located. See 21 U.S.C.
    16
    § 387l(a)(1)(B). Other manufacturers have sought review in
    other circuits of orders denying approval to market flavored
    ENDS, with some courts denying and others granting stays of
    enforcement pending review. See Breeze Smoke, LLC v. FDA,
    
    18 F.4th 499
     (6th Cir. 2021) (opinion denying stay), cert.
    denied, 
    142 S. Ct. 638
     (2021) (mem.); My Vape Order v. FDA,
    No. 21-71302, ECF No. 18 (9th Cir. 2021) (order denying stay
    of enforcement); Gripum LLC v. FDA, No. 21-2840, 
    2021 WL 8874972
     (7th Cir. Nov. 4, 2021) (order granting stay), Bidi
    Vapor LLC v. FDA, No. 21-13340-DD (11th Cir. Feb. 1, 2022)
    (order granting stay).
    To date, only the Fifth Circuit has reached the merits of
    FDA denial orders like those challenged here. On the eve of
    issuance of this opinion, that court in Wages & White Lion
    Investments, LLC d/b/a Triton v. FDA (Triton), No. 21-60766,
    
    2022 WL 2799797
     (July 18, 2022), denied two e-liquid
    manufacturers’ petitions for review. Id. at *1. The court
    rejected as “blatantly wrong” the manufacturers’ contention
    that the Tobacco Control Act does not authorize the FDA to
    consider comparative cessation benefits of flavored over
    unflavored or tobacco-flavored products. Id. at *4. And the
    court denied the manufacturers’ various arbitrary and
    capricious challenges. See id. at *5-11. It held that the FDA
    adequately explained the shortcomings of the manufacturers’
    study, considered relevant differences between “open” and
    “closed” e-cigarette device types, did not assess applications
    under evidentiary or substantive requirements different from
    those communicated to the regulated parties, and adequately
    justified its decision not to review the manufacturers’
    marketing plans (or, alternatively, committed only harmless
    error). Id. The court accordingly denied the manufacturers’
    petitions for review. Id. at *11.
    17
    Judge Jones dissented on the ground that, in her view, the
    orders are arbitrary and capricious. Id. at *12-19; see 
    16 F.4th 1130
     (5th Cir. 2021) (motions panel granting stay on similar
    reasoning). She would have held the FDA’s decision to not
    review the manufacturers’ marketing plans “obviously illogical
    and unreasonable,” 
    2022 WL 2799797
     at *16, and rejected the
    majority’s view that any error was harmless, id. at *17. She
    also would have held that the FDA took a “meandering
    administrative course” that, without notice, altered the
    substantive and evidentiary requirements manufacturers were
    expected to meet. Id. at *18. Her analysis tracked that of the
    earlier motions panel in the same case, which had stayed the
    FDA’s order and held the manufacturers were likely to succeed
    on their arbitrary and capricious claims. See id. at *16 (quoting
    and citing 16 F.4th at 1137).
    The only other published opinion to date on flavored
    ENDS product marketing orders is the Sixth Circuit’s opinion
    in Breeze Smoke, LLC v. FDA, denying an e-liquid
    manufacturer’s petition for a stay based on its failure to show a
    likelihood of success. 18 F.4th at 503. For reasons later
    adopted by the Fifth Circuit merits panel in Triton, the court
    sustained the FDA’s determination that Breeze failed to meet
    its evidentiary requirements, explaining that the FDA’s
    statement in its 2019 Guidance that it was willing to “consider”
    additional forms of evidence did not require it to accept such
    evidence as sufficient to meet the statute’s requirement. Id. at
    507. Relatedly, the court was unpersuaded that the FDA’s
    Guidance had changed applicants’ evidentiary burden without
    notice. The agency, the court observed, has consistently
    required applicants to submit randomized controlled trials,
    longitudinal studies, or other similarly rigorous evidence. Id.
    at 506-07. Commenting that the FDA probably should have
    more thoroughly considered applicants’ marketing and youth
    prevention plans or better explained why it did not, the court
    18
    held that potential shortcoming did not in any event establish a
    likelihood of success to justify a stay. Id. at 507-08.
    II. DISCUSSION
    A. Jurisdiction, Standing, and Standard of Review
    The Tobacco Control Act confirms our jurisdiction to
    review the FDA’s denial orders.             See 21 U.S.C.
    § 387l(a)(1)(B). And the manufacturers have standing to
    challenge the FDA’s marketing denial orders, which deny them
    the authorization the Tobacco Control Act requires before they
    may lawfully sell their products.
    The manufacturers assert that the FDA exceeded its
    statutory authority under the Tobacco Control Act by requiring
    applicants to show their flavored e-liquids carry sufficiently
    greater benefits than non-flavored e-liquids to outweigh their
    relatively greater risks. Because we conclude the statute is best
    read to support the FDA’s action, we need not consider whether
    or how much deference to accord its interpretation. The
    manufacturers also argue that the FDA’s denial order was
    arbitrary and capricious in several respects. We review such
    challenges to the FDA’s exercise of its Tobacco Control Act
    authority under the ordinary APA standard of review. 21
    U.S.C. § 387l(b) (citing 
    5 U.S.C. § 706
    (2)(A)). Under section
    706 we assess whether the agency offered a “satisfactory
    explanation for its action” and hold arbitrary and capricious
    explanations that “entirely fail[] to consider an important
    aspect of the problem.” Motor Vehicle Mfrs. Ass’n v. State
    Farm Mut. Auto. Ins. Co., 
    463 U.S. 29
    , 43 (1983). In so doing,
    we must “judge the propriety of [an agency’s] action solely by
    the grounds invoked by the agency.” SEC v. Chenery Corp.,
    
    332 U.S. 194
    , 196 (1947). Our review incorporates the APA’s
    prejudicial error rule, under which the “burden of showing that
    19
    an error is harmful normally falls upon the party attacking the
    agency’s determination.” Shinseki v. Sanders, 
    556 U.S. 396
    ,
    409 (2009) (citing 
    5 U.S.C. § 706
    ).
    B. Challenge to FDA’s Statutory Authority
    Congress directed the FDA to authorize the marketing of
    only those new tobacco products that an applicant has shown
    “would be appropriate for the protection of the public health.”
    21 U.S.C. § 387j(c)(2)(A). The distinct public health hazards
    of flavored tobacco products, especially to young people, are
    extensively documented. Given those risks, purveyors of
    flavored products cannot show they are appropriate in public
    health terms without establishing that they have substantial
    public health benefits that overcome their risks. The FDA
    accordingly requires applicants seeking to market flavored
    tobacco products to show their products are more beneficial to
    the public health than non-flavored products.
    Petitioners challenge that requirement as contrary to the
    Act. They assert that the FDA lacks statutory authority to
    consider a product’s “relative effectiveness at promoting
    cessation of combustible cigarette use versus another product
    with an otherwise similar health risk profile and labeling.”
    Pet’rs Br. at 50. But the Tobacco Control Act itself instructs
    that, in seeking an FDA determination that their product is
    appropriate for the protection of the public health, an applicant
    must supply “full reports of all information . . . concerning
    investigations which have been made to show the health risks
    of such tobacco product and whether such tobacco product
    presents less risk than other tobacco products.” 21 U.S.C.
    § 387j(b)(1)(A) (emphasis added). The Act then provides that
    the FDA “shall deny an application . . . if, upon the basis of the
    information submitted . . . and any other information before the
    [FDA],” it concludes that the applicant has failed to “show[]
    20
    that permitting [the] product to be marketed would be
    appropriate for the protection of the public health.” Id.
    § 387j(c)(2). In other words, the statute not only allows but
    expressly instructs the FDA to consider evidence regarding just
    the comparison that the manufacturers say the FDA lacks
    statutory authority to make.
    The FDA acted well within that statutory directive when it
    compared the claimed cessation benefits of flavored and non-
    flavored products. The FDA has found that flavored products
    present greater risks than other tobacco products, based on a
    robust array of literature showing the dangers those products
    pose of hooking new users, especially youth. See FDA
    Technical Review at 5-9. Instead of stopping there and
    denying the applications for flavored products as
    comparatively risky, it addressed their asserted upsides,
    reasoning that a product could still be net beneficial if its large
    risks were overcome by larger benefits to current users. See id.
    at 10-14. By contrast, if the new product carried greater risks
    but no overmatching greater benefits, authorizing it would not
    on balance serve public health. That is precisely the type of
    analysis the statute calls for.
    The manufacturers contend that the statutory phrase “the
    health risks of such tobacco product” limits the FDA to
    comparing only the “physiological health risks” of individual
    tobacco products without taking account of a “broader concept
    of risk that encompasses initiation and cessation behaviors.”
    Pet’rs Reply Br. at 12-13. The statutory text is to the contrary.
    The degree to which a harmful product entices and addicts new
    users is inarguably a component of the “health risk” it poses.
    That is plain from Congress’s express directive that the FDA
    determine whether a product is “appropriate for the protection
    of the public health,” a population-wide inquiry. 21 U.S.C.
    § 387j(c)(2)(A) (emphasis added); see also Health, BLACK’S
    21
    LAW DICTIONARY (11th ed. 2019) (defining “public health” as
    “[t]he health of the community at large” or “the general body
    of people or the community en masse”).
    The manufacturers are wrong that the FDA applied a
    standard akin to or more stringent than the “safe and effective”
    standard to which new drugs are subject or conflated its
    statutory inquiry with the “modified risk tobacco products”
    inquiry.     See Pet’rs Br. at 50-54 (citing 
    21 U.S.C. §§ 355
    (b)(1)(A), 387k). Those distinct standards apply to
    other kinds of approvals contingent on evidentiary showings
    that do not apply here and that the FDA did not demand. See
    
    21 U.S.C. § 355
    (b)(1)(A) (requiring evidence that new drug is
    effective for therapeutic use, which the manufacturers do not
    claim of e-cigarette liquids); 
    id.
     § 387k (requiring evidence
    substantiating specific modified risk claims, which the
    manufacturers do not seek to make here). Moreover, the fact
    that the FDA has other authorities through which it can approve
    other products, like those designed and approved specifically
    as smoking cessation products, does not release the FDA from
    following its statutory mandate here to approve only tobacco
    products the sale of which it determines “would be appropriate
    for the protection of the public health.” 21 U.S.C. § 387j(c)(2).
    The manufacturers give us no persuasive reason to think that
    those other authorities somehow limit the inquiry the FDA may
    make in reaching a § 387j determination.
    C. Arbitrary and Capricious Challenges
    The manufacturers also contend that the FDA’s denial of
    their marketing applications was arbitrary and capricious.
    They raise two principal arguments. First, they argue the FDA
    misdirected applicants by altering both the types of evidence it
    would accept and the comparison it required applicants to
    make. Second, they argue the FDA failed to reasonably explain
    22
    its decision not to review the manufacturers’ individual
    marketing plans. They more briefly make a handful of other
    arguments, also addressed below.
    We hold that the FDA did not misdirect applicants. And,
    assuming the FDA insufficiently explained its non-review of
    applicants’ marketing plans, we hold that error was harmless.
    The manufacturers’ other arbitrary and capricious challenges
    fail as well. We accordingly deny the petitions for review.
    1.   The “Surprise Switcheroo” Challenge Fails
    The manufacturers argue that the FDA’s 2019 Guidance
    rendered its denial orders arbitrary and capricious because the
    guidance steered them astray. Agencies must explain changes
    in position, particularly once a prior position has engendered
    regulated parties’ reliance. See FCC v. Fox Television Stations,
    Inc., 
    556 U.S. 502
    , 514-16 (2009); PHH Corp. v. CFPB, 
    839 F.3d 1
    , 44-49 (D.C. Cir. 2016), vacated and reinstated in
    relevant part, 
    881 F.3d 75
    , 83 (D.C. Cir 2018) (en banc). The
    manufacturers assail the FDA’s denial orders as departing from
    its 2019 Guidance in two ways: They argue the FDA (1)
    changed the types of evidence it expected applicants to
    produce, and (2) changed the substantive comparison it
    expected applicants to make. Because those changes conflicted
    with the 2019 Guidance, the manufacturers say, the FDA acted
    without fair notice of the requirements their applications had to
    meet to gain approval. See Pet’rs Reply Br. at 3 (citing SNR
    Wireless LicenseCo., LLC v. FCC, 
    868 F.3d 1021
    , 1043 (D.C.
    Cir. 2017)).
    The manufacturers’ notice claim effectively boils down to
    an assertion that the FDA’s 2019 Guidance affirmatively
    misdirected them. They do not claim insufficient notice based
    on the statutory standard or the FDA’s deeming rule. Indeed,
    23
    they seem to acknowledge that, had the agency not issued its
    2019 Guidance, they would have no claim of inadequate notice.
    See Oral Argument Tr. at 5-6. The manufacturers instead argue
    that the FDA’s 2019 Guidance suggested the agency would
    approve the type of application they filed, making its rejections
    unexpected and arbitrary. But the FDA’s final determinations
    were consistent with the 2019 Guidance, undercutting their
    claim.
    a.   No change to requisite types of evidence
    The manufacturers argue that the FDA without warning
    altered the types of evidence it would accept. Specifically, they
    claim that the 2019 Guidance suggested that applicants need
    not produce data from randomized controlled trials or
    longitudinal studies, and that the FDA here suddenly reversed
    course by effectively requiring those forms of evidence.
    We disagree. The FDA did not reverse course. The 2019
    Guidance said that randomized controlled trials or longitudinal
    studies would not be necessary if applicants submitted
    similarly rigorous “valid scientific evidence.” 2019 Guidance
    at 12. In the orders under review, the agency found that these
    applicants’ evidence was not similarly rigorous. As the Sixth
    Circuit reasoned in Breeze Smoke, the FDA said only that “it
    might accept evidence other than long-term studies, if that
    evidence had sufficient scientific underpinnings” to meet the
    statutory standard. 18 F.4th at 506-07. The FDA nowhere
    guaranteed that unspecified other forms of evidence would
    necessarily be sufficient—only that they might be, so the FDA
    would consider them. 2019 Guidance at 12-13.
    The text of the FDA’s 2019 Guidance makes that clear.
    The agency stated that it “intends to review” evidence in forms
    other than randomized controlled trials or longitudinal studies
    24
    “to determine whether it is valid scientific evidence sufficient
    to demonstrate that” the statutory standard is met. 2019
    Guidance at 12. The FDA thereby broadened the types of
    evidence it would consider: Instead of limiting applicants to
    the two types of evidence it usually requires, the agency
    allowed manufacturers to submit evidence in other forms. But
    at the same time the agency made clear it would not relax the
    scientific rigor of the requisite public health demonstration.
    The agency’s finding that the evidence was insufficiently
    rigorous does not reflect a changed standard, but the
    manufacturers’ failure to meet the standard the agency
    consistently applied.
    Nor did the FDA act arbitrarily and capriciously by finding
    the manufacturers’ evidence insufficiently rigorous.
    Prohibition Juice’s own literature review concluded that “there
    is not enough evidence from well-designed studies to
    determine whether e-cigarette flavors aid in smoking
    cessation.” J.A. 469. The manufacturers argue that the FDA
    failed to credit data they collected through online voluntary
    surveys. But the FDA explained that one-time assessments and
    consumer perception surveys “do[] not enable reliable
    evaluation of behavior change over time” and that their lack of
    product-specific comparisons deprive them of probative
    weight. FDA Technical Review at 12-13. The FDA
    accordingly concluded that, “in contrast to the evidence related
    to youth initiation—which shows clear and consistent patterns
    of real-world use that support strong conclusions—the
    evidence regarding the role of flavors in promoting switching
    among adult smokers is far from conclusive.” Id. at 11.
    Considered in light of the evidence before the agency, that
    conclusion was entirely reasonable.
    The manufacturers argue that, even if the FDA nominally
    claimed it would accept other evidence, the agency effectively
    25
    engaged in an arbitrary “fatal flaw” analysis to reject
    applications lacking either of the two leading types of evidence.
    Pet’rs Br. at 16. As they see it, the FDA in practice considered
    only whether applicants had submitted data from randomized
    controlled trials or longitudinal cohort studies. Id. But the
    material the manufacturers rely on itself directly refutes that
    characterization.
    First, they point to the check-box forms the FDA used to
    assess applications. But they omit that those forms looked
    beyond randomized trials and longitudinal studies to list a third
    category of potential support: “Other evidence in the
    [application] related to potential benefit to adults.” See J.A.
    32-33, FDA Br. at 43. The manufacturers’ problem, per that
    document, was not their failure to include longitudinal or
    randomized controlled studies. It was their failure to include,
    as the FDA consistently required, studies sufficiently rigorous
    to show a benefit of flavored e-cigarette products sufficient to
    overcome their risks.
    Second, the manufacturers point to an internal agency
    guidance memorandum dated July 9, 2021, as evidence of this
    fatal flaw approach. See J.A. 159-60. The July memorandum’s
    prediction that applications lacking evidence from randomized
    controlled trials or longitudinal studies would “likely” be
    denied did not necessarily foreclose reliance on other forms of
    rigorous evidence. Id. at 160. In any event, the FDA replaced
    that memorandum the next month, on August 17, 2021, with
    superseding guidance that expressly required the agency to
    consider other forms of evidence if sufficiently robust. See J.A.
    161-62; see also J.A. 162 n.ix. That August memorandum
    preceded the FDA’s rejection of petitioners’ applications.
    The manufacturers also contend the FDA imposed an
    evidentiary “double standard” by using literature reviews as
    26
    evidence for flavored products’ risks but eschewing literature
    reviews as evidence of their benefits. The FDA explained that
    its treatment of various materials depended on the nature and
    conclusiveness of the findings they reported. From its study of
    reviews of the scientific evidence on the risks of flavored
    products, the agency concluded that those risks “are understood
    as a matter of scientific consensus.” Breeze Smoke, 18 F.4th at
    508; see FDA Technical Memorandum at 11 (noting that risks
    to youth are “clear and consistent”). But the reports of
    evidence of flavored products’ benefits, the agency found, were
    “far from conclusive” and “quite mixed,” particularly due to
    relevant differences from product to product. FDA Technical
    Memorandum at 11. The agency reasonably drew differing
    conclusions from evidence of differing strength.
    Finally, the manufacturers urge us to adopt the reasoning
    of the Fifth Circuit panel in its decision to grant a stay in Triton.
    That stay was in place as this case was briefed and argued, but
    has been superseded by the decision on the merits.
    Nonetheless, we consider on its own terms and are unpersuaded
    by the stay panel’s analysis. See 
    2022 WL 2799797
     at *5-11;
    18 F.4th at 506-07. The stay panel, and merits dissent in
    accord, over-read the FDA’s statement that it would consider
    evidence other than long-term studies as announcing that
    “long-term studies were likely unnecessary.” 
    16 F.4th 1140
    -
    41. Against that asserted baseline, the stay opinion concluded
    that the FDA’s rejection of Triton’s application showed the
    agency “changed its mind and required the very thing it said it
    would not—namely, long-term studies of e-cigarettes.” Id. at
    1135. But again, the FDA has all along required “valid
    scientific evidence,” and its denial orders explained how the
    survey data petitioners submitted fell short of the mark.
    27
    b.   No change to substantive standard
    The manufacturers also argue that the FDA pulled a bait-
    and-switch of the substantive standard it applied in reviewing
    their applications. See Pet’rs Reply Br. at 4-8. The
    manufacturers argue they relied on the FDA’s 2019 Guidance,
    which included a section describing the types of “comparison
    products” applicants should reference to show their products’
    benefits. See 2019 Guidance at 13-14. There, the FDA
    emphasized that applicants should compare their products to
    “tobacco products in the same category or subcategory.” Id. at
    13. But the manufacturers claim they were unfairly surprised
    to see the FDA explain in its denial order that it looked for
    evidence “that could potentially demonstrate [an] added benefit
    to adult users of flavored ENDS [electronic nicotine delivery
    system] over an appropriate comparator tobacco-flavored
    ENDS.” Pet’rs Reply Br. at 5 (citing J.A. 47, 823, 1029, 1236).
    The manufacturers contend that “nobody reading [the 2019
    Guidance] would believe that it was necessary to compare a
    particular e-liquid to a tobacco-flavored e-liquid,” id. at 6-7,
    and that accordingly “FDA flunked Petitioners for failing to
    answer a question that it never even asked,” id. at 8. They
    claim that doing so both worked a change to the substantive
    standard of review and upset their interest in reliance on the old
    standard.
    This argument is far off base. The governing statute
    expressly asks for evidence concerning whether an applicant’s
    “tobacco product presents less risk than other tobacco
    products,” 21 U.S.C. § 387j(b)(1)(A), and the FDA’s 2019
    Guidance told manufacturers that the agency would look for
    comparisons between the proposed product and “tobacco
    products in the same category or subcategory,” 2019 Guidance
    at 13. Petitioners knew they needed to show that their flavored
    e-liquids were sufficiently beneficial to adult smokers to offset
    28
    the risks from flavored products’ particular attractiveness to
    youth. It was widely known when petitioners prepared and
    submitted their applications that the FDA had identified e-
    cigarette flavors as a driver of soaring youth rates of tobacco
    uptake, use, and addiction. Petitioners’ own unflavored or
    tobacco-flavored e-liquids were an obvious, otherwise-similar
    comparator against which to gauge whether the added risks of
    their flavored e-liquids are overcome by those products’ added
    benefits to adult smokers. The manufacturers’ own insistence
    that device type is the primary feature driving ENDS popularity
    among youth does not render arbitrary or surprising the FDA’s
    attention to the relative risks and benefits of flavored versus
    unflavored products of the same type.
    The manufacturers cannot identify any misdirection in the
    2019 Guidance. The FDA’s product-specific analysis in the
    denial orders is fully consistent with its Guidance. The 2019
    Guidance identified what types of comparisons the FDA would
    be looking for. The denial orders applied that guidance to
    examine whether the added risk of these manufacturers’
    flavored e-liquids over otherwise-comparable products without
    flavoring is outweighed by greater added benefit to adult
    smokers of the flavored over unflavored versions. That is a
    straightforward application of the FDA’s stated standard.
    There was nothing new about the FDA’s review of the
    manufacturers’ applications that deprived them of fair warning.
    See Breeze Smoke, 18 F.4th at 507. Because the 2019 Guidance
    gave fair notice of the analysis the agency would perform and
    the purpose of those comparisons, we hold the agency did not
    create unfair surprise by focusing on comparisons between
    otherwise similar flavored and nonflavored products.
    29
    2.   The FDA’s Decision Not to Review Each Youth Access
    Plan Was Immaterial
    The manufacturers also argue that the FDA acted
    arbitrarily and capriciously by failing to reasonably explain
    why it did not review their individual marketing plans. They
    make plausible arguments that the agency erred in acting as it
    did without a more persuasive explanation.           But the
    manufacturers did not show that that error prejudiced them in
    any way. We accordingly hold that, even assuming the FDA’s
    explanation was error, that error was harmless.
    In their briefing, and even when specifically pressed on the
    point at argument, the manufacturers were unable to identify
    any prejudice they suffered from the FDA’s lack of
    individualized review of their plans to prevent youth access to
    their flavored e-liquids. The Tobacco Control Act applies the
    APA’s standard of review, see 21 U.S.C. § 387l(b), which
    instructs courts to take “due account . . . of the rule of
    prejudicial error” and thereby incorporates a harmless error
    rule, 
    5 U.S.C. § 706
    ; see Nat’l Assn. of Home Builders v.
    Defenders of Wildlife, 
    551 U.S. 644
    , 659-60 (2007). Under that
    rule, “the burden of showing that an error is harmful normally
    falls upon the party attacking the agency’s determination.”
    Shinseki v. Sanders, 
    556 U.S. 396
    , 409 (2009); see Air Canada
    v. Dep’t of Transp., 
    148 F.3d 1142
    , 1156 (D.C. Cir. 1998).
    When an agency’s mistake plainly “had no bearing” on the
    substance of its decision, we do not grant a petition for review
    based on that mistake. See Mass. Trs. of E. Gas & Fuel Assocs.
    v. United States, 
    377 U.S. 235
    , 248 (1964).
    We apply that harmless error rule consistent with SEC v.
    Chenery Corp., which requires courts to refrain from assessing
    agency action on bases the agency itself did not supply. 
    332 U.S. at 196
    . “[W]ith limited exception,” our circuit has noted,
    30
    Chenery “does not allow us to affirm an agency decision on a
    ground other than that relied upon by the agency.” Manin v.
    NTSB, 
    627 F.3d 1239
    , 1243 (D.C. Cir. 2011). But “when there
    is not the slightest uncertainty as to the outcome of a
    proceeding on remand, courts can affirm an agency decision on
    grounds other than those provided in the agency decision.” 
    Id.
    at 1243 n.1 (quoting Envirocare of Utah, Inc. v. Nuclear Regul.
    Comm’n, 
    194 F.3d 72
    , 79 (D.C. Cir. 1999)) (formatting
    modified); accord Grossmont Hosp. Corp. v. Burwell, 
    797 F.3d 1079
    , 1086 (D.C. Cir. 2015). Chenery, the Supreme Court has
    elaborated, was designed to “assur[e] that initial administrative
    determinations are made with relevant criteria in mind.” Mass.
    Trs. of E. Gas & Fuel, 
    377 U.S. at 248
    . When an asserted error
    clearly did not affect the outcome, applying Chenery and its
    progeny “would not advance the purpose they were intended to
    serve.” 
    Id.
     In short, “Chenery does not require that we convert
    judicial review of agency action into a ping-pong game,”
    lobbing the matter from agency to court and back. NLRB v.
    Wyman-Gordon Co., 
    394 U.S. 759
    , 766 n.6 (1969). Where a
    petitioner had ample opportunity yet failed to show that an
    agency error harmed it, vacatur and remand to give the agency
    an opportunity to fix the error is unwarranted.
    The manufacturers raise serious arguments that the FDA
    erred in deciding not to review their marketing plans on the
    ground that they presented nothing new, and that its
    explanation for the non-review fell short insofar as the FDA
    assumed the contents of plans without reading them. But those
    plans are in the record for all to read, and they vindicate the
    FDA’s assumption. Even the manufacturers do not claim that
    FDA’s consideration of their marketing plans could have
    changed the agency’s decision on their applications. The
    measures they highlight in their marketing plans are not
    materially different from those the FDA had previously found
    insufficient to stem the surge in youth e-cigarette use. In their
    31
    briefing and at argument petitioners identified examples of the
    youth access limitations they proposed and that they assert the
    FDA erred in not specifically reviewing. See Pet’rs Br. at 39;
    Oral Argument Tr. at 12. Yet their plans—to require
    customers’ self-verification of age at the point of sale and to
    use what they characterize as less vibrant marketing
    unappealing to youth—track measures the FDA in its 2020
    guidance deemed inadequate to prevent or otherwise materially
    limit youth access to flavored ENDS. Compare Pet’rs Br. at
    39, with 2020 Guidance at 42-44. The manufacturers fail to
    explain why their proposals will prevent youth access where
    other, similar measures did not.
    Petitioners thus cannot identify how they were harmed
    from the FDA’s failure to consider essentially the same
    measures it had previously rejected. Indeed, they offered no
    refutation whatsoever to the FDA’s pointed assertions that the
    manufacturers “do not claim to have proposed access measures
    different from those that FDA previously found inadequate,”
    and accordingly that “there is no basis to conclude that any
    harm flowed from the asserted failure-to-consider error.”
    Compare FDA Br. at 38-39, with Pet’rs Reply Br. at 8-9. In
    response to questioning on the point at oral argument, the
    manufacturers again did not identify any harm they
    experienced from FDA’s failure to have reviewed their
    marketing plans, instead simply referring to the familiar and
    demonstrably inadequate measures listed in their opening brief.
    See Oral Argument Tr. at 12 (responding “well, no” to the
    question whether manufacturers’ plans had proposed “anything
    qualitatively different” from measures the FDA had previously
    examined and deemed lacking); id. at 15 (responding “no” to
    the question whether manufacturers’ marketing plans would
    alone have altered the FDA’s analysis enough to warrant
    granting the petition, absent their other challenges to purported
    changing FDA guidance). In light of that failure, the
    32
    petitioners have also forfeited any argument that the alleged
    error prejudiced them.
    We accordingly assume without deciding that the FDA
    erred in not individually reviewing the manufacturers’
    marketing plans and offering an apparently circular
    explanation for that approach. The manufacturers’ inability to
    identify how the FDA’s denial orders could have come out
    differently if only it had known the contents of their plans
    defeats their request for vacatur and remand to the FDA for
    further consideration.
    3.   The Other Arbitrary and Capricious Challenges Fail
    None of the manufacturers’ other arbitrary and capricious
    challenges has merit. See Pet’rs Br. at 34-49; Reply Br. at 8-11.
    The manufacturers contend the FDA ignored a material
    distinction between open and closed systems.              These
    manufacturers seek to market e-liquids used to refill open
    systems, and they say the FDA erred in treating public health
    data regarding the risks of youth access to flavored closed-
    system e-cigarettes as applicable to flavored products used with
    open systems. But the FDA did acknowledge the distinct
    products, noting in its denial orders that “there may be
    differential appeal of certain product styles.” FDA Technical
    Memorandum at 7. The FDA then reasonably explained that it
    nonetheless found the scientific literature about public health
    risks to youth applicable to petitioners’ products, because
    “across these different device types, the role of flavor is
    consistent.” Id. The FDA cited data from the 2020 National
    Youth Tobacco Survey, among other sources, to support its
    conclusion that youth preference for flavor “is consistently
    demonstrated across large, national surveys and longitudinal
    cohort studies.” Id.
    33
    By contrast, the FDA noted that youth preferences for
    different device types are “fluid,” and that youth readily shift
    among devices. Id. at 8. For example, the FDA cited data
    showing that “the removal of one flavored product option
    prompted youth to migrate to another [device type] that offered
    their desired flavor options.” Id. This fact “underscore[d] the
    fundamental role of flavor in driving appeal.” Id. The FDA
    supported its conclusion with substantial evidence, and we
    have no basis to second-guess it.
    The FDA also did not impermissibly treat like products
    differently, as the manufacturers contend. The FDA concedes
    that it inadvertently denied approval to some manufacturers
    who had submitted results from randomized controlled trials
    comparing their flavored products to non-flavored cigarettes;
    the agency reports that it is reconsidering those applications
    separately. See FDA Br. at 47-48; see also FDA 28(j) Letter
    (dated Apr. 13, 2022) at 2. But the manufacturers here do not
    contend that they submitted similar studies for their products.
    Accordingly, there is no inconsistency between the FDA’s
    distinct treatment of these different applications.
    Finally, the FDA was not required to consider alternative
    regulatory approaches before denying the manufacturers’
    applications for premarket approval. The statute requires that
    applicants make a certain showing before their products can be
    approved for sale and provides that, where an applicant fails to
    make that showing, the FDA “shall deny” the application. See
    21 U.S.C. § 387j(c)(2)(A). After reviewing their applications,
    the FDA here found that these manufacturers had failed to
    make the requisite showing. The statute requires no more.
    34
    III. CONCLUSION
    For all of the above reasons, we deny the petitions for
    review.
    So ordered.
    KATSAS, Circuit Judge, concurring: This case arises from
    the Food and Drug Administration’s denial en masse of
    thousands of applications for permission to sell flavored e-
    cigarettes or liquid cartridges for use in flavored e-cigarettes.
    The FDA denied the applications primarily because flavored e-
    cigarettes appeal to children. Yet the agency refused even to
    consider any of the proposed marketing plans for these
    products, which bear critically on the risk that they pose to
    children. The FDA reasoned that because marketing plans it
    had previously reviewed were inadequate, the agency could
    simply stop reviewing the plans for other products, “for the
    sake of efficiency.” FDA, Technical Project Lead (TPL)
    Review of PMTAs (2021), at 11 n.xix (J.A. 44). The FDA earns
    points for candor, but the Administrative Procedure Act
    requires more. As the Fifth Circuit has explained, “it’s
    unreasonable for the FDA to stop looking at proposed
    [marketing] plans because past ones have been
    unpersuasive.” Wages & White Lion Invs., LLC v. FDA, 
    16 F.4th 1130
    , 1137 (5th Cir. 2021); see also Breeze Smoke, LLC
    v. FDA, 
    18 F.4th 499
    , 507 (6th Cir. 2021) (“The FDA likely
    should have more thoroughly considered Breeze Smoke’s
    marketing plan.”). 1
    Despite the FDA’s obvious error, I join the Court’s
    opinion in full. As Judge Pillard persuasively demonstrates,
    the petitioners here made no serious argument that the FDA’s
    failure to consider their marketing plans was prejudicial, as
    required for them to obtain relief under the APA. See 
    5 U.S.C. § 706
     (“due account shall be taken of the rule of prejudicial
    1
    The Fifth Circuit later held that the FDA’s failure to consider
    the full marketing plans at issue in Wages & White Lion Investments
    was not arbitrary. Wages & White Lion Invs., LLC v. FDA, No. 21-
    60766, slip op. at 19–23 (5th Cir. 2022); but see 
    id.
     at 32–35 (Jones,
    J., dissenting). In that case, however, the FDA claimed to have
    reviewed at least “a summary of the marketing plans.” Id. at 22
    (majority). Here, the FDA did not claim to have done even that.
    2
    error”). Moreover, I agree that the petitioners’ other arguments
    lack merit. In joining the Court’s opinion, I do not understand
    it to foreclose the possibility of our finding prejudicial error in
    other cases where manufacturers press the prejudice point more
    forcefully.