The Biologics Price Competition and Innovation Act

In March 2015, FDA approved filgrastim-sndz, a biosimilar to the white-blood-cell-stimulating protein filgrastim, as the first biosimilar in the United States. It came five years after the Biologics Price Competition and Innovation Act was signed on March 23, 2010, as Title VII of the Affordable Care Act¹. As of its October 28, 2026 update, FDA's biosimilar product list² showed 90 biosimilar approvals referencing 21 different biologics.

Most of those approvals are recent. FDA cleared 18 biosimilars in 2024 and another 18 in 2025, together 40 percent of everything approved under the law, by GxRadar's count of the agency's list. Nine more had been approved in 2026 by the end of October.

The 2010 law, whose short title calls it the act “of 2009,” did for biologics roughly what the 1984 Hatch-Waxman Act did for chemical drugs. It created an abbreviated approval route, a fixed period of protection for the original product, a separate status for products that can be substituted at the pharmacy and a patent-exchange process for settling disputes before launch. This history covers each piece and how FDA's approach has shifted since.

The 351(k) pathway

Section 7002 added subsection (k) to section 351 of the Public Health Service Act. Anyone may apply to license a product as “biosimilar” to a reference biologic by submitting analytical studies showing it is “highly similar” notwithstanding minor differences in clinically inactive components, animal studies and clinical studies. FDA may decide in its discretion that one of those elements is unnecessary, the statute¹ says. The product must also share the reference product's route of administration, dosage form and strength. Each application may be compared with only one reference product, and it is reviewed by the same FDA division that oversees that product.

That standard differs from the sameness test for a small-molecule generic. FDA's consumer explainer³ says an approved biosimilar has no clinically meaningful differences in safety, purity or potency from its reference product and is made from the same types of sources, such as living cells. GxRadar compares the two systems in how biosimilars differ from generics.

Scientific expectations have moved since 2010. In September 2025 FDA finalized guidance on the comparative analytical assessment⁷ that underpins every application, and in November 2025 it issued draft guidance with updated recommendations on when comparative efficacy studies are needed⁶, meaning clinical studies with efficacy endpoints that compare a proposed product with its reference product. In March 2026 it opened another round of comment on its question-and-answer guidance on the act⁸.

Twelve years of exclusivity, and four

Protection for reference products is written as two clocks, both counted from the date the reference product was first licensed. FDA may not make a biosimilar approval effective until 12 years after that date, and may not accept a biosimilar application until four years after it. A sponsor that completes pediatric studies FDA requests gets six months added to each clock, the same reward described in GxRadar's article on pediatric exclusivity.

By comparison, a new small-molecule drug gets five years of new chemical entity exclusivity, with a generic patent challenge allowed after four.

Interchangeable biosimilars

A second, higher status sits above biosimilarity. An interchangeable product must be biosimilar and be expected to produce the same clinical result as the reference product in any given patient. For a product given more than once, the risk of alternating or switching between it and the reference product must be no greater than the risk of staying on the reference product. An interchangeable product “may be substituted for the reference product without the intervention of the health care provider who prescribed the reference product,” according to the definition in the law¹.

Whether a pharmacist can actually make that swap is governed by state law, as FDA's explainer³ notes. GxRadar covers the state rules in state generic substitution laws and FDA's listing of these products in the Purple Book and interchangeable biosimilars.

FDA has narrowed what it asks for to prove interchangeability. Its 2019 interchangeability guidance dealt at length with switching studies, in which patients alternate between products. In a June 2024 draft update⁵, the agency said experience had shown that for biosimilars approved to date, “the risk in terms of safety or diminished efficacy is insignificant following single or multiple switches,” and that its view of when switching studies are needed “has evolved.”

The patent dance

Subsection (l) of the law set out a private exchange of information that lawyers nicknamed the patent dance. Within 20 days after FDA accepts a biosimilar application for review, the applicant provides it and manufacturing information to the reference product sponsor. Within 60 days the sponsor lists the patents it believes could be asserted, and the applicant has 60 days to answer with its own list and arguments. The applicant must give notice at least 180 days before it begins commercial marketing.

In 2017 the Supreme Court ruled⁹ that the requirement to hand over the application is not enforceable by injunction under federal law, and that “an applicant may provide notice” of commercial marketing before obtaining FDA licensure. Under that second holding, the 180-day clock can run while FDA's review is still under way.

Biosimilar makers have also challenged patents at the patent office through inter partes review. A 2025 commentary in Health Affairs Scholar¹⁰ cited research finding that those reviews invalidated 14 of 20 patents that stood in the way of biosimilar entry, and that median revenue for the brand product fell 79 percent in the year after a patent was invalidated. The same authors documented a sharp rise in 2025 in the patent office's refusals to hear such challenges.

Insulin and the 2020 transition

Some protein products, including insulin, human growth hormone and pancreatic enzymes, had historically been approved as drugs under the Food, Drug, and Cosmetic Act. The act moved them into the biologics framework after a 10-year transition. On March 23, 2020, their approved applications were “deemed to be a license” under the Public Health Service Act, FDA's transition page⁴ says, and only after that could companies seek biosimilar or interchangeable versions of them. FDA's list now includes insulin glargine and insulin aspart biosimilars, three each.

GxRadar's tally of FDA's list shows how approvals have spread across reference biologics and years.

Adalimumab and denosumab lead with 10 listed biosimilars each, followed by pegfilgrastim and ustekinumab with eight each. Aflibercept, bevacizumab and trastuzumab have six apiece.

Fees and the 2027 renewal

Biosimilar review is paid for in part by a user fee program Congress added in 2012, the Biosimilar User Fee Act, enacted as Title IV of the FDA Safety and Innovation Act¹². Its current version, BsUFA III, expires in September 2027. FDA held a public meeting on its proposed recommendations for fiscal 2028 through 2032 on October 26, 2026, and is accepting written comments until November 25, 2026, according to its Federal Register notice¹¹. The notice says BsUFA III included a pilot program focused on advancing interchangeable products. Congress has to pass the next version by September 30, 2027, the same deadline it faces for the brand and generic fee programs.