Mechanism-of-action claims not generally established may be misleading without disclosure

AI-verifiedwarningBinding lawRaised as a question — a person decides

Rule

An ad may be misleading if it makes a claim about a drug's mechanism or site of action that is not generally regarded as established by scientific evidence by experts qualified by scientific training and experience, without disclosing that the claim is not established and the limitations of the supporting evidence.

Check

For any mechanism-of-action or site-of-action claim, verify whether qualified experts generally regard it as established by scientific evidence; if not, confirm the ad discloses that the claim is not established and discloses the limitations of the supporting evidence.

Escalate when

Whether qualified experts generally regard the mechanism claim as established requires scientific/medical judgment.

Where this comes from

21 CFR 202.1(e)(7)(vi). The highlighted words are quoted exactly; a script confirms they appear in the source before the rule can be published.

…) Uses reports or statements represented to be statistical analyses, interpretations, or evaluations that are inconsistent with or violate the established principles of statistical theory, methodology, applied practice, and inference, or that are derived from clinical studies the design, data, or conduct of which substantially invalidate the application of statistical analyses, interpretations, or evaluations. (vi) Contains claims concerning the mechanism or site of drug action that are not generally regarded as established by scientific evidence by experts qualified by scientific training and experience without disclosing that the claims are not established and the limitations of the supporting evidence. (vii) Fails to provide sufficient emphasis for the information relating to side effects and contraindications, when such information is contained in a distinct part of an advertisement, because of repetition or other emphasis in that part of the advertisement of claims for effectiveness or safety of the drug. (viii) Fails to present information relating to side effects and contraindications with a prominence and r…

Open the original at these words on ecfr.gov ↗Read our full copy →

Document: 21 CFR 202.1
Version: 2026-09-16 — the link above is pinned to this date, so it shows the text as it stood then
Retrieved: 2026-09-21 from www.ecfr.gov
Fingerprint: a542640a872b3f2702d549e8…

Applies when

Naturepromotional

How this rule was checked

Citation proven by script and passed an independent verifier running on a different model. Not yet confirmed by a human.

Drafted
claude-code:sonnet · 2026-09-21
Independent verification — revise
claude-code:opus · 2026-09-21
Reviewer's reasons
- The quote is item (vi) of 21 CFR 202.1(e)(7) and is reproduced accurately and in full, so the substance is supported.
- Overstated in both the title and the rule statement. (e)(7) is prefaced by 'An advertisement may be false, lacking in fair balance, or otherwise misleading or otherwise violative of section 502(n) of the act if it:'. The rule converts that into a hard obligation - title 'must disclose lack of established scientific support', body 'must disclose that they are not established, along with limitations of the supporting evidence'. This is exactly the 'may be misleading written as is prohibited' failure. Note the contrast with US-SUB-005, which cites the same (e)(7) chapeau and correctly kept 'may'.
- The source does not state an affirmative labeling-style disclosure duty; it identifies undisclosed non-established mechanism claims as a factor that may render the advertisement misleading. The rule should state it that way.
- Atomic: the source frames the disclosure as one combined obligation ('that the claims are not established and the limitations of the supporting evidence'), so treating it as one checkable item is acceptable and does not bundle independent requirements.
- determinism 'judgment' is correct: whether a mechanism or site-of-action claim is 'generally regarded as established by scientific evidence by experts qualified by scientific training and experience' turns on expert consensus, not presence/absence.
- authority 'binding' is correct: 21 CFR 202.1 is a regulation.
- Severity 'warning' is defensible and consistent with the permissive framing of (e)(7); it is also inconsistent with the 'must' wording of the rule statement, which is further evidence the wording is overstated.
- Locator '21 CFR 202.1(e)(7)(vi)' matches the quoted text exactly; applies_when 'promotional' is justified because the section governs prescription-drug advertisements.
Revised by the drafter
claude-code:sonnet · 2026-09-21
Independent verification — pass
claude-code:opus · 2026-09-21
Reviewer's reasons
- The quote is the complete text of 21 CFR 202.1(e)(7)(vi) and the locator matches it exactly.
- The rule statement retains the source's conditional framing ('may be misleading'), consistent with the (e)(7) chapeau, 'An advertisement may be false, lacking in fair balance, or otherwise misleading or otherwise violative of section 502(n) of the act if it'. It does not convert a presumptive factor into an absolute prohibition.
- The rule preserves the qualifying standard 'not generally regarded as established by scientific evidence by experts qualified by scientific training and experience' rather than flattening it to 'unproven', and it preserves the cure the source contemplates — disclosure that the claim is not established and disclosure of the limitations of the supporting evidence. The trigger is therefore correctly stated as an undisclosed unestablished mechanism claim, not as a ban on mechanism claims.
- Atomic: one enumerated factor, one check. The two disclosure elements ('not established' and 'limitations of the supporting evidence') are joined in the source as a single cure for the same conduct, not as two independent obligations.
- 'Judgment' is correct — whether qualified experts generally regard a mechanism claim as established, and whether a disclosure adequately conveys the limitations, cannot be settled by presence/absence or literal match. The escalate condition names this.
- Authority 'binding' is correct (codified FDA regulation). Severity 'warning' is defensible and matches the presumptive character of (e)(7) as against the conclusive (e)(6) list. applies_when is limited to promotional material, which the source supports and which adds no invented limit.