Supplement Innovation Act is a Good Start, but Does Not Yet Live Up to the Hype

Representative Diana Harshbarger deserves credit for putting drug preclusion squarely before Congress. On Sept. 10, 2026, she introduced H.R. 10336, the Dietary Supplement Innovation Act, to address a framework that is ambiguous, opaque, and capable of blocking food and dietary supplement uses long after meaningful drug development has ended. That problem is real, and a congressional vehicle is overdue.

Most of the major dietary supplement trade associations were therefore right to welcome congressional engagement. H.R. 10336 protects pre-DSHEA ingredients, preserves the first-to-market principle, directs FDA to consider differences between drug and supplement uses, makes certain FDA preclusion assertions immediately reviewable, places the burden on the United States in those proceedings, and removes the duplicative drug-exclusion provision in section 201(ff)(3). Those are real improvements over current law.

However, public statements surrounding the bill promise transparency, an end to perpetual preclusion, and a science-based pathway. The operative language does not yet deliver those results. The sponsor-released text cites the wrong regulatory subsection for Phase 3, invokes a statutory subsection that does not exist, and directs FDA’s difference-factor analysis to paragraphs structured as exceptions rather than clearly making it part of the governing preclusion standard. The first two issues are readily correctable. The third is substantive. More importantly, the bill’s central trigger and sunset provisions remain structurally weak.

That does not mean the trades were wrong to support introduction. It means enthusiasm arrived faster than scrutiny. Their most useful role now is to convert political momentum into durable statutory text.

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What H.R. 10336 Gets Right

The bill’s strongest reform is procedural. FDA should not be able to announce that a product violates section 301(ll) through a warning letter, notification response, or website statement and then resist review because the communication is supposedly nonfinal. H.R. 10336 makes specified assertions immediately reviewable and assigns the burden of proof to the government. That is meaningful.

The bill also uses careful language for products marketed before Oct. 15, 1994, recognizing that a product sold before DSHEA could not literally have been labeled as a “dietary supplement” under a definition that did not yet exist. And striking section 201(ff)(3) is essential. Reforming section 301(ll) while retaining a separate, differently worded exclusion in the dietary supplement definition would preserve needless ambiguity.

Why Significant Revision Is Still Necessary

The Phase 2 Trigger May Weaken Current Law

The most consequential defect is the replacement of “substantial clinical investigations” with any publicly disclosed Phase 2 or Phase 3 investigation. That is not necessarily a higher or clearer substantive threshold. It may be lower.

Current law at least permits an argument that a small exploratory study is not “substantial.” H.R. 10336 would make the Phase 2 label sufficient without regard to the number of subjects dosed, the study design, the endpoint, the dose tested, whether the trial was completed, or whether the sponsor ever progressed beyond proof of concept.

FDA’s binding regulation does not create legally distinct Phase 2A and Phase 2B categories. It defines Phase 2 broadly. FDA guidance recognizes the practical continuum: Phase 2A may involve early exposure-response, biomarker, or proof-of-concept work, while Phase 2B ordinarily includes patient dose-ranging before Phase 3. H.R. 10336 nevertheless treats the entire category alike.

A 20- or 25-patient proof-of-concept study could therefore carry the same nationwide preclusive consequence as a 300-patient randomized, multi-dose Phase 2B program. Both may be called Phase 2, but they do not reflect the same scientific maturity, investment, or likelihood that an approved drug will emerge. An early exploratory study may be worthwhile; it should not automatically create a market-exclusion right over a separate statutory category.

Congress should not delete “substantial.” It should define it. A qualifying investigation could be tied to the first dosed subject in Phase 3, a specified aggregate number of subjects actually dosed in Phase 2 or later development, or a narrowly tailored pivotal-study rule for rare diseases. There is nothing talismanic about 300 subjects, an 18-month milestone period, or a 10-year outside limit. Those are negotiable legislative lines. The need for objective measures of actual human exposure, continued development, and a finite term is not.

The Seven-Year Clock May Never Begin

The bill’s abandonment provision is promoted as ending perpetual preclusion, but it applies only when each relevant Phase 2 or Phase 3 investigation has been “on inactive status, withdrawn, or both” for seven continuous years, unless the sponsor publicly announces discontinuation.

Those terms do not map cleanly onto an individual completed trial. Under FDA regulations, inactive status applies to the IND, not ordinarily to a single investigation. FDA may place an IND on inactive status after specified periods of no enrollment or clinical hold, but mere dormancy does not automatically produce that status. Withdrawal likewise generally concerns the IND. By contrast, a normally concluded study is typically identified publicly as completed, not inactive or withdrawn.

Consider the predictable case: a sponsor completes a 25-person Phase 2 proof-of-concept trial, leaves the IND open, and never conducts a robust dose-ranging study. When does the seven-year period begin — last patient last visit, the posted completion date, an FDA inactive-status determination, withdrawal of the IND, or a voluntary sponsor announcement? H.R. 10336 does not say. On a literal reading, the clock may not begin at all.

Under another plausible application, the industry could wait through the regulatory period before FDA may place a dormant IND on inactive status and then another seven years. Neither result supplies the promised certainty.

The solution is a date-certain rule based on substantive development milestones, not litigation over when a “ghost” protocol became abandoned. Preclusion should terminate automatically after a defined period without actual enrollment and dosing, completion and submission of a study report, active review of an NDA or BLA, or diligent work to resolve a clinical hold or complete-response letter. Merely keeping an IND open, filing an annual report, amending a protocol, or holding an FDA meeting should not preserve exclusion.

An outside maximum term is also necessary because even a genuinely active program can otherwise maintain preclusion indefinitely. A sunset without a defined sunrise is not a sunset.

An FDA-Initiated Override Is Not an Accessible Petition Pathway

H.R. 10336’s proposed section 301(ll)(7) is not a process for determining that an article falls outside drug preclusion. It is an affirmative statutory override: even when an article is otherwise precluded, FDA may, in the Secretary’s discretion, issue an administrative order approving its use in food, including a dietary supplement. That authority could be valuable, but the bill reserves both initiation and decision to FDA. A manufacturer, ingredient supplier, trade association, consumer organization, or other interested person has no right to invoke the process, develop a record, or obtain a decision by a date certain.

Congress should make the override petitionable. The Secretary should be able to proceed on the agency’s own initiative, and any interested person should be permitted to petition for an order authorizing a specified use notwithstanding preclusion. The petitioner should demonstrate, based on published and publicly available evidence, that the proposed use is generally recognized as safe under its conditions of use and is reasonably expected, when consumed under the proposed conditions, to support or maintain normal structure or function or to promote general well-being — the existing DSHEA formulation — rather than to diagnose, mitigate, treat, cure, or prevent disease.

FDA should determine completeness within 30 days, provide public notice and an opportunity for the affected drug sponsor and other interested parties to comment, and issue a reasoned public order within 180 days, subject to one limited extension. Because this mechanism affirmatively permits an otherwise precluded use, agency inaction should be deemed a denial subject to immediate judicial review, not an automatic safe harbor or product approval.

Any order should be limited to the substance, route, serving amount, population, and conditions of use before the agency. This override should remain separate from a materially different-use determination: one asks whether preclusion applies; the other permits use even when it does.

A Factor List Is Not a Material-Equivalence Standard

Requiring FDA merely to “consider” route, dosage, composition, and safety does not establish a controlling rule. FDA could acknowledge every difference and still decide that chemical identity controls. The statute should provide that preclusion applies only when the proposed food or supplement use is materially equivalent to the protected drug use, based on route, exposure, dosage, composition, intended use, claims, mechanism, and comparative safety.

FDA will object that proving material equivalence is more burdensome than acknowledging a list of factors. The answer is a divided burden. The requester should make a prima facie showing of material difference and submit the relevant evidence. The party seeking to preserve preclusion should then bear the ultimate burden of persuasion. FDA would not have to prove material equivalence in every routine matter — only when it chooses to invoke section 301(ll) and its position is disputed.

Preclusion Must Be Transparent and Finite

H.R. 10336 creates no post-approval sunset. Once an article is approved as a drug, section 301(ll) may continue to exclude food or supplement use after patents and congressionally granted non-patent exclusivity have expired. That turns preclusion into an undefined shadow exclusivity.

Congress should tie post-approval preclusion to the latest expiration of any initial statutory non-patent exclusivity that actually protects the relevant drug use, including an extension of that initial period. If five-year new-chemical-entity exclusivity and seven-year orphan exclusivity both attach at initial approval, the later date should control only for the orphan-protected use. A biologic’s applicable statutory exclusivity would control for the licensed use. Later indications, formulations, dosage forms, supplemental applications, ownership transfers, or different sponsors should not restart the clock. Patents would remain enforceable on their own terms but should not extend section 301(ll).

Transparency also requires more than a public clinical-trial record. A sponsor seeking investigational preclusion should file a public notice identifying the article, qualifying investigation, protected use, trigger date, current development status, and expiration date. The rule should be simple: no public notice, no investigational preclusion, and no retroactive claim based on secret development activity.

Preclusion and Product Lawfulness Are Separate Questions

Section 301(ll) should answer only whether preclusion applies. A materially different-use determination would neither approve a product nor excuse compliance with applicable safety, new dietary ingredient, labeling, drug-definition, or FTC standards; FDA should not demand food-use GRAS status merely to determine that an otherwise lawful dietary ingredient is not precluded. That is distinct from the paragraph (7) override, for which Congress may impose GRAS as a heightened condition because the order affirmatively permits an otherwise precluded use.

Congress should also prevent private plaintiffs from using an alleged section 301(ll) violation as the predicate for an “illegal product” consumer claim, while preserving claims based on independently false advertising, personal injury, warranty, or deception. Otherwise, certainty against FDA will not produce marketplace certainty.

A Durable Framework

Drug developers deserve meaningful protection for meaningful investment, not secret, dormant, or perpetual control over a separate regulatory category. A durable statute should make preclusion public, earned, maintained, finite, use-specific, and reviewable. A no-preclusion determination should remove section 301(ll) as a barrier and nothing more; an override order should authorize only the specified conditions of use.

Improve the Vehicle, Do Not Declare Victory

Rep. Harshbarger has created an important vehicle. The trade associations were right to support congressional engagement. But support for introduction should not be mistaken for proof that the present language has solved the problem. An FDA-initiated override is not an accessible petition pathway. Seven years measured from an undefined regulatory status is not a reliable sunset. A factor list without a legal consequence is not a material-equivalence standard. And a statute with no post-approval end date does not end perpetual preclusion.

The worst outcome is not that Congress fails to enact H.R. 10336. The worse outcome would be for the industry and Congress to mistake momentum for sound legislation and enact a weak statutory framework that FDA can administer around, and then invoke that very enactment as evidence that Congress considered drug preclusion and chose to preserve broad agency authority.

After Loper Bright, a court would not defer to FDA merely because the statute is ambiguous. It would independently determine the best reading of the statutory text. But if Congress replaces the current “substantial clinical investigations” standard with an expansive Phase 2 trigger, leaves the seven-year clock uncertain, and preserves an indefinite post-approval bar, FDA would have a powerful argument that its restrictive interpretation is not simply agency policy, but the interpretation Congress itself chose to enact.

The task now is to refine the text so that it actually delivers the transparency, predictability, and end to perpetual preclusion promised in its public rollout. Congress should make preclusion public, earned, maintained, use-specific, reviewable, and finite. The industry should welcome the beginning of this effort without mistaking the beginning for the end.