Overview
On September 10, 2026, Representative Diana Harshbarger introduced H.R. 10336, the Dietary Supplement Innovation Act, which proposes significant amendments to the Federal Food, Drug, and Cosmetic Act's ("FDCA") drug-preclusion framework. The legislation addresses longstanding questions regarding the interaction between section 301(ll) of the FDCA and the parallel drug-exclusion provision in the dietary supplement definition under section 201(ff)(3).
The bill would replace portions of the existing framework with more specific statutory criteria, add procedural protections for regulated parties, and eliminate the separate drug-exclusion provision in section 201(ff)(3). Major dietary supplement trade associations, including the American Herbal Products Association, the Consumer Healthcare Products Association, and the Council for Responsible Nutrition, have publicly supported introduction of the legislation.
As H.R. 10336 moves through the legislative process, companies in the dietary supplement, food, pharmaceutical, and life sciences sectors should review the bill and monitor any amendments.
What H.R. 10336 Proposes
The Dietary Supplement Innovation Act would make several principal changes to existing law.
Replacing the current investigational-drug trigger. Current section 301(ll) refers to a drug for which "substantial clinical investigations" have been instituted and made public. H.R. 10336 would replace that formulation with a trigger based on publicly disclosed Phase 2 or Phase 3 clinical investigations.
Protecting certain pre-DSHEA products. The bill would expressly protect drugs or biological products marketed before October 15, 1994, as food or in products that would have satisfied the subsequently enacted definition of a dietary supplement, other than the labeling requirement.
Preserving prior food or supplement marketing. The legislation would continue to protect substances marketed as food or in a dietary supplement before the relevant drug approval, biologic licensure, or qualifying clinical investigation.
Creating exceptions for inactivity and discontinuation. H.R. 10336 would provide an exception where each relevant Phase 2 or Phase 3 investigation has been on inactive status, withdrawn, or both for a continuous period of at least seven years, or where the sponsor has publicly announced discontinuation of drug-development activities.
Replacing the current rulemaking pathway with an administrative-order process. Current section 301(ll) allows the Secretary, after notice and comment, to approve an otherwise precluded food use by regulation. H.R. 10336 would instead authorize approval by administrative order through a proceeding initiated by the Secretary.
Directing FDA to consider differences between uses. A new section 413A would direct FDA, in specified drug-preclusion determinations, to consider differences between the drug and the substance as used in food or a dietary supplement, including route of administration, recommended dosage and serving amount, concentration or composition, and safety.
Providing immediate judicial review. Certain FDA communications asserting a violation of section 301(ll)—including warning letters, specified notification responses, and statements on FDA-controlled websites—would be immediately reviewable in court without regard to whether the communication constitutes final agency action. The United States would bear the burden of proving the section 301(ll) violation.
Eliminating the parallel dietary supplement exclusion. The bill would strike section 201(ff)(3), eliminating the separately worded drug-exclusion provision from the definition of "dietary supplement."
Areas Stakeholders Should Be Watching
Certain provisions of H.R. 10336 warrant particular attention as the legislation proceeds through committee consideration and potential markup.
1. Scope of the Phase 2 Trigger
H.R. 10336 would replace the current statutory reference to "substantial clinical investigations" with a trigger tied specifically to publicly disclosed Phase 2 or Phase 3 investigations. The change could narrow the current standard in one respect while potentially broadening it in another.
Current section 301(ll) does not expressly limit "substantial clinical investigations" to any particular phase of clinical development. By identifying Phase 2 and Phase 3 specifically, H.R. 10336 would establish a more defined boundary and could exclude investigations conducted at earlier stages of development that might otherwise be argued to satisfy the current substantiality standard.
At the same time, the bill would remove the separate requirement that the clinical investigations be "substantial." FDA's regulation at 21 C.F.R. § 312.21 treats Phase 2 as a broad regulatory category and does not separately define Phase 2A and Phase 2B. FDA guidance and drug-development practice nevertheless recognize that Phase 2 may encompass both relatively early proof-of-concept and exposure-response studies and larger dose-ranging programs undertaken in preparation for Phase 3. As a result, a publicly disclosed investigation that qualifies as Phase 2 could satisfy the proposed statutory trigger without a separate inquiry into whether the investigation is substantial.
The practical effect of the change therefore may depend on the types of investigations that fall within the Phase 2 category and how the new standard is applied. As the bill proceeds through the legislative process, stakeholders may wish to monitor whether Congress further defines the level of clinical development necessary for preclusion to attach, including through an enrollment threshold, a specified development milestone or other objective criteria.
2. Operation of the Seven-Year Inactivity Provision
The seven-year inactivity provision would add a potential endpoint for investigational preclusion that is not expressly contained in current section 301(ll).
Questions may arise, however, regarding how the provision would operate in practice. FDA's existing regulations generally address "inactive status" and withdrawal in the context of an investigational new drug application ("IND"), while an individual clinical study may simply reach completion without the underlying IND being placed on inactive status or withdrawn.
The introduced text does not expressly specify how the seven-year period would be calculated for a completed Phase 2 or Phase 3 study where the underlying IND remains open or other development activity continues. Further statutory or regulatory clarification may therefore be considered regarding the event that begins the seven-year period and the circumstances in which continued development maintains preclusion.
3. Administrative-Order Authority for Otherwise Precluded Uses
H.R. 10336 would replace the current notice-and-comment regulation pathway with an administrative order, issued in the Secretary's discretion, allowing an otherwise precluded food or dietary supplement use.
This provision is distinct from a determination that section 301(ll) does not apply. It would instead allow FDA to authorize a specified food or supplement use notwithstanding otherwise applicable preclusion.
The introduced bill provides for a proceeding initiated by the Secretary and does not establish a corresponding petition right for manufacturers, ingredient suppliers, trade associations, or other interested parties. As the legislation develops, Congress may consider whether interested persons should be permitted to request such an order and, if so, what safety, intended-use, evidentiary, timing, and procedural standards should govern FDA's review.
4. Legal Significance of Differences Between Drug and Supplement Uses
The bill would direct FDA to consider differences between a drug and the substance as used in food or a dietary supplement, including differences in route of administration, dosage or serving amount, concentration or composition, and safety.
Congress may consider specifying the legal consequence of those differences. For example, Congress could specify when differences are sufficiently material that the food or dietary supplement use should be treated as outside the scope of drug preclusion, as well as how the respective burdens of production and persuasion should be allocated.
5. Post-Approval Preclusion
The bill's seven-year inactivity provision addresses investigational programs. Once a drug is approved or a biological product is licensed, however, H.R. 10336 does not establish a defined endpoint for post-approval preclusion.
Congress may therefore consider whether post-approval preclusion should continue indefinitely or should be tied to an identifiable period, potentially including an applicable statutory nonpatent exclusivity period.
6. Transparency and Notice
The legislation requires the existence of the relevant clinical investigations to have been made public but does not establish a dedicated drug-preclusion registry.
Additional transparency provisions could include public identification of the potentially precluded article, the qualifying clinical investigation, the date on which preclusion began, the sponsor, the relevant protected use, and the status of continuing development.
Such a mechanism could provide greater certainty for both pharmaceutical developers and companies evaluating potential food or dietary supplement uses.
7. Private Litigation Considerations
H.R. 10336 addresses federal enforcement and judicial review but does not expressly address whether an alleged section 301(ll) violation may serve as a predicate for state-law consumer protection, unfair competition, warranty, or similar claims.
Companies should continue to assess potential private litigation exposure independently of FDA enforcement risk as the legislation develops.
8. Technical Drafting Issues
The introduced text contains apparent cross-reference issues, including its reference to 21 C.F.R. § 312.21(b) for both Phase 2 and Phase 3 (Phase 3 is addressed in § 312.21(c)) and to section 402(ff) of the FDCA. These types of technical issues are commonly addressed through subsequent revisions or committee markup and do not necessarily reflect the ultimate form of the legislation.
Practical Considerations
As H.R. 10336 proceeds through the legislative process, affected companies may wish to:
- Review existing product portfolios to identify ingredients or products potentially affected by the current drug-preclusion framework or by the changes proposed in H.R. 10336.
- Evaluate relevant clinical-development programs to understand how the proposed Phase 2/Phase 3 trigger and seven-year inactivity provision could affect substances that are also used or proposed for use in food or dietary supplements.
- Document prior marketing evidence for ingredients that may qualify for the bill's pre-1994 or first-to-market protections.
- Monitor amendments and committee activity concerning the preclusion trigger, inactivity period, administrative-order authority, difference-factor analysis, and post-approval treatment.
- Evaluate litigation exposure separately from FDA enforcement risk, including potential state-law theories based on alleged drug preclusion.
- Consider providing technical input through appropriate trade associations or directly during the legislative process on provisions that could materially affect existing or planned products.
Conclusion
H.R. 10336 represents a significant development in congressional consideration of the FDCA's drug-preclusion framework. The legislation addresses several recurring issues under current law and provides a vehicle for further consideration of when preclusion should attach, how it should be maintained, and when it should end.
The introduced text is likely to receive technical and policy refinement as it proceeds through the legislative process. Companies across the dietary supplement, food, pharmaceutical, and life sciences sectors should monitor developments, evaluate how potential amendments could affect product development, market access, and regulatory strategy, and consider providing input on provisions that may have a significant impact on their business.