This bill remakes the legal treatment of interchangeability for biological products licensed under section 351(k) of the Public Health Service Act. Instead of a separate FDA determination that a biosimilar is “interchangeable,” the statute would generally deem a biosimilar licensed under 351(k) to be interchangeable with its reference product, subject to limited exceptions tied to existing exclusivity for pre‑enactment interchangeable products.
The measure also requires the Department of Health and Human Services to update and reissue guidance documents to align with the statutory changes.
The change removes the regulatory pathway that has required additional switching studies and formal FDA determinations for interchangeability. That reduces an administrative and scientific hurdle for market entry, with immediate implications for substitution at the pharmacy-level, contracting, and pricing; it also raises questions about incentives to generate switching evidence and how the FDA and states will handle postmarket monitoring and substitution policies.
At a Glance
What It Does
The bill deletes the separate interchangeability determination in section 351(k) and provides that a biological product licensed under that subsection will be deemed interchangeable with its reference product, subject to a narrow exception tied to existing first‑interchangeable exclusivity for certain pre‑existing products. It sets a 60‑day transition window after enactment and preserves any unexpired first‑interchangeable exclusivity periods that existed on enactment.
Who It Affects
Biosimilar applicants and originator biologic sponsors, pharmacies and pharmacists (who implement substitution), payers and pharmacy benefit managers that contract on interchangeability, and the FDA (which must rewrite guidance and adjust review practices). State pharmacy substitution regimes will interact with, but are not directly changed by, this federal deeming.
Why It Matters
By eliminating the separate interchangeability pathway, the bill lowers the time and evidence costs associated with market entry for biosimilars and could accelerate price competition and substitution. At the same time, it alters the commercial and regulatory incentives that drove investment in switching studies and created statutory exclusivities, with practical consequences for market structure and for how safety and effectiveness of substituted products are monitored.
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What This Bill Actually Does
The bill amends section 351(k) of the Public Health Service Act so that the statute no longer requires a specific FDA finding that a biosimilar is “interchangeable” with its reference product. Instead, a biosimilar licensed under 351(k) is presumptively interchangeable with its reference product once it is licensed under that pathway.
The text defines a transition mechanism so that products licensed before the specified transition date are covered, and it preserves limited protections for certain existing interchangeable exclusivity periods.
Practically, the statute draws two timing lines. If a biosimilar is licensed on or after the transition date (60 days after enactment), it is deemed interchangeable upon licensure unless it depends on the same reference product as another biologic that both (1) had licensure in effect before the bill’s enactment and (2) enjoyed an unexpired first‑interchangeable exclusivity period on the relevant date.
If those conditions exist, the new biosimilar only becomes deemed interchangeable when that pre‑existing exclusivity ends. For products already licensed before the transition date, the bill deems them interchangeable on the transition date, subject to the same exclusivity caveat.
The bill also explicitly preserves any unexpired first‑interchangeable exclusivity periods that applied before enactment.Beyond the core interchangeability language, the bill makes several conforming edits to related statutes — for example, removing cross‑references that treated interchangeability as a separate legal standard elsewhere in the Public Health Service Act and the Federal Food, Drug, and Cosmetic Act — and it revises the FDCA pediatric new‑active‑ingredient language to reflect the change in interchangeability treatment. Finally, the bill requires the Secretary of HHS to revise or revoke prior FDA guidances on interchangeability and to issue updated guidance on the data needed to demonstrate biosimilarity; the law gives FDA specific 18‑month windows to produce and finalize those guidance documents.
The bill closes by saying these amendments do not change the underlying biosimilarity standard and do not limit the FDA’s authority to require whatever information it deems necessary to license a product as biosimilar.
The Five Things You Need to Know
The bill removes the separate statutory pathway for an FDA interchangeability determination and generally deems a 351(k)‑licensed biological product interchangeable with its reference product.
Deeming takes effect either upon licensure for products licensed after the transition date or on the transition date for products licensed before it; the transition date is 60 days after enactment.
An exception delays deeming when a newly licensed biosimilar relies on the same reference product as a biologic that had licensure before enactment and had a first‑interchangeable exclusivity period still in effect; in that case, deemed interchangeability waits until that exclusivity expires.
The bill requires the Secretary to update or revoke existing FDA guidances on interchangeability and to issue revised guidance on biosimilarity and required data, with an 18‑month deadline to update draft/final guidances and an additional 18 months after the comment period for revised versions.
Conforming edits strike references to separate interchangeable biosimilars elsewhere in PHSA and the FDCA and amend section 505B(l) (pediatric new‑active‑ingredient rules) to reflect that 351(k) products are not treated as new active ingredients merely because of interchangeability.
Section-by-Section Breakdown
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Short title — Biosimilar Red Tape Elimination Act
Provides the Act’s short title. Mechanically important for citations and reference in subsequent legal texts and guidance but carries no substantive regulatory change.
Eliminate separate interchangeability determination; restructure 351(k)
Rewrites subsection 351(k) to remove the separate statutory interchangeability finding and reorganizes internal paragraphs and clause numbering. The practical effect is to convert interchangeability from an affirmative FDA finding into a statutory presumption for biological products licensed under 351(k), subject to the limitations the bill lays out elsewhere.
Automatic deeming on licensure or transition date, with exclusivity carve‑out
Creates the core rule: a product licensed under 351(k) will be deemed interchangeable with its reference product. It then sets two timing rules — one for products licensed on or after the 60‑day transition date, and one for products licensed before the transition date — and a single carve‑out that defers deeming if the product relies on a reference product that is already the subject of a pre‑enactment licensed biological with an unexpired first‑interchangeable exclusivity period. This provision balances immediate substitution authority with protection for pre‑existing exclusivity holders.
Preserve pre‑enactment first‑interchangeable exclusivity; conforming statutory changes
Affirms that any unexpired first‑interchangeable exclusivity periods in effect before enactment remain in force for their original duration. The bill also amends related statutory provisions — PHSA 351(i)(3), PHSA 352A, various FDCA cross‑references, and FDCA section 505B(l) — to remove language that assumed interchangeability required a separate finding or that treated biosimilars as new active ingredients under certain pediatric determinations.
FDA guidance revision deadlines
Directs the Secretary to revise or revoke prior interchangeability guidances and to issue or revise guidance on biosimilarity data for 351(k) applications. The statute gives FDA 18 months after enactment to update draft and final guidance (including specified prior documents) and then another 18 months after the comment period closes to issue revised drafts or finals — creating hard windows for regulatory clarity that FDA must meet or explain if not met.
Preserve biosimilarity standard and FDA authority to require information
Clarifies that the amendments do not change the existing statutory standard for licensure as biosimilar under 351(k) and do not limit FDA’s authority to request data and information necessary to support a biosimilarity determination. This tries to limit legal challenges that the deeming approach implicitly weakens the scientific standard for approval.
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Explore Healthcare in Codify Search →Who Benefits and Who Bears the Cost
Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- Biosimilar manufacturers: They avoid the additional evidentiary and trial burden historically associated with demonstrating interchangeability, lowering development costs and time‑to‑market for 351(k) applicants.
- Pharmacies and pharmacists: Clearer federal deeming simplifies substitution decisions where state laws permit automatic substitution for interchangeable products, reducing administrative friction at dispensing.
- Payers and PBMs: Faster market entry and easier substitution raise the prospect of increased competition and lower net prices for biologics covered in formularies and benefit designs.
- Patients (especially those on biologic therapies): Greater likelihood of lower out‑of‑pocket costs and broader access to biosimilar options if substitution increases and competition compresses prices.
Who Bears the Cost
- Originator biologics sponsors seeking interchangeability exclusivity in the future: The bill reduces the value of pursuing separate interchangeability designations going forward because the deeming mechanism will grant interchangeability without additional switching data.
- Manufacturers that invested in switching studies anticipating premium interchangeability market value: Those sunk costs will not necessarily translate to exclusive substitution privileges under the new statutory regime.
- FDA and regulators: Although the bill reduces case‑by‑case interchangeability reviews, the agency must produce multiple revised guidances within set timeframes and manage postmarket surveillance, pharmacovigilance, and naming/labeling implications without additional statutory resources.
- State pharmacy boards and pharmacies navigating state substitution laws: The federal deeming may create operational and legal ambiguity where state statutes and rules differ on substitution criteria, increasing compliance complexity at the point of care.
Key Issues
The Core Tension
The bill trades higher evidentiary thresholds and slower market entry for greater near‑term competition by eliminating the separate interchangeability finding, creating a classic policy dilemma: accelerate access and lower prices now, or preserve incentives for robust switching data and exclusivity that can strengthen confidence in substitution and reward early innovators. There is no clean fix that simultaneously maximizes competition, maintains pre‑enactment exclusivity value, and preserves the original incentives that generated interchangeability data.
The bill resolves one regulatory bottleneck — the need for a separate interchangeability finding — but does so by statutory deeming rather than by setting new scientific criteria. That raises implementation questions: FDA guidances will need to clarify whether any minimal switching data remain necessary for labeling, for claims made in promotional materials, or for confidence among clinicians; the statute preserves FDA’s authority to require information, but the line between necessary and discretionary data becomes politically and legally salient.
The exclusivity carve‑out protects pre‑enactment first‑interchangeable holders, but only in a narrow way tied to products that relied on the same reference product and had licensure in effect before enactment. That creates a complex sequencing issue: market entrants will need to map which reference products are encumbered by active exclusivities and when those exclusivities expire, potentially driving strategic timing of licensing and commercialization.
Finally, the practical effect on pharmacy substitution depends on state laws and insurer contracting; federal deeming does not automatically harmonize substitution rules across states, and ambiguity about traceability, naming (suffixes), and postmarket safety signals could increase liability and coordination costs for health systems and payers.
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