From Dance to Battleground: How Biosimilars Reach the Finish Line

[1]

When people hear that the FDA approved a new generic medicine, some might expect to find it at their local pharmacy in a matter of weeks. For biosimilars, however, getting FDA approval is merely the opening act.[2] The intended purpose of biosimilars is to provide the everyday consumer with lower-cost alternatives that are just as safe and effective as brand-name biologics.[3] A biosimilar is a type of biologic that is made to be highly similar to an existing FDA-approved brand-name drug.[4] Biologics are derived from living cell structures designed to treat autoimmune diseases, certain kinds of cancers, and other chronic conditions.[5] In effect, biosimilars are meant to save developers time and resources by eliminating the need to duplicate expensive clinical trials that have already proven effective.[6] Given the potential conflicts with patent thickets and the financial risk that comes with bringing an FDA-approved biosimilar to market, this is no easy feat.[7] 

To balance lowering the costs of drugs with incentives for medical innovation, Congress enacted the Biologics Price Competition and Innovation Act (“BPCIA”) in 2010.[8] The statute establishes a pre-litigation process known as the “Patent Dance.”[9] As soon as a biosimilar application is accepted for review by the FDA, the biosimilar applicant has twenty days to hand over its confidential manufacturing dossier to the brand-name sponsor, known as the Reference Product Sponsor (“RPS”).[10] Over the next several months, the parties exchange detailed lists of asserted patents and any legal contentions regarding non-infringement or invalidity.[11] The exchange leads to waves of litigation and eventually requires the applicant to provide the RPS with a formal notice at least 180 days before commercially marketing its product to the public.[12] 

Following the Supreme Court’s decision in Sandoz Inc. v. Amgen Inc.,[13] an injunction under federal law is no longer available to enforce the initial disclosure of a biosimilar applicant’s manufacturing files, rendering an applicant’s participation in the Patent Dance a tactical option.[14] If an applicant chooses to “dance,” the statute is given the opportunity to limit the number of patents that the RPS can assert in early litigation.[15] In contrast, if an applicant opts out of the “dance,” the RPS can immediately file a patent infringement lawsuit on any relevant patents from its thicket.[16]

This high-stakes procedural strategy is best illustrated in the ongoing BPCIA battle between Regeneron Pharmaceuticals and Amgen over Eylea, a biologic injected into the eye to prevent vision loss.[17] When Amgen sought approval for its biosimilar, Pavblu, the company used a buffer-free formulation, allowing the applicant to claim that its product did not infringe on any of Regeneron’s patents.[18] Per BPCIA, Regeneron asserted its patent portfolio, leading to litigation.[19] In recent years, Amgen defeated Regeneron’s motion for a preliminary injunction which would have prevented Amgen from releasing its product to the market.[20] Consequently, Amgen executed an “At-Risk Launch,” a strategy where a manufacturer of a biosimilar can commercialize its product while patent litigation with the brand-name drug is still on-going.[21] In response, Regeneron secured tailored patents that explicitly covered the buffer-free formulations, suing Amgen once more.[22] 

As seen here, the BPCIA information exchange was designed to streamline patent resolution, but in practice, tactical maneuvers have turned the Patent Dance into a patent battleground.[23] While biosimilar applicants can leverage precise R&D designs to dodge preliminary injunctions, RPS can tailor new patent claims directly to a competitor’s process.[24] The fight to reach the market continues long after the FDA approves a drug, and the exchange of information under the BPCIA is just the beginning.[25] 

References

[1] Photo by JSB Co., A Woman Getting Her Eye Examined by a Doctor, Unsplash (Feb. 27, 2023),  https://unsplash.com/photos/a-woman-getting-her-eye-examined-by-a-doctor-mdNRCVL4ZgY.

[2] See Mastering the Dance: A Strategic Guide to the BPCIA Biosimilar Patent Timeline Litigation, DrugPatentWatch (Jan. 8, 2026), https://www.drugpatentwatch.com/blog/mastering-the-dance-a-strategic-guide-to-the-bpcia-biosimilar-patent-timeline-and-litigation/.

[3] See What Is a Biosimilar? Benefits, Costs & Employer Savings Explained, SmithRx (Apr. 22, 2025), https://smithrx.com/blog/biosimilars-101-understanding-the-basics-and-benefits.

[4] See id.

[5] See Biosimilars Basics for Patients, U.S. Food & Drug Admin. (Aug. 1, 2024), https://www.fda.gov/drugs/biosimilars/biosimilars-basics-patients.

[6] See Sarfaraz Niazi, Biorationality: The FDA Sets Sights on Removing Clinical Efficacy Studies for Biosimilars, MJH Life Scis. (Oct. 29, 2025), https://www.centerforbiosimilars.com/view/biorationality-the-fda-sets-sights-on-removing-clinical-efficacy-studies-for-biosimilars.

[7] See Biologic Patent Thickets: How They Work, Why They’re Losing, and What Comes Next, DrugPatentWatch (Apr. 20, 2026), https://www.drugpatentwatch.com/blog/revolutionizing-the-fight-against-biologic-drug-patent-thickets/.

[8] See 42 U.S.C. § 262 (2018).

[9] See Mastering the Dance: A Strategic Guide to the BPCIA Biosimilar Patent Timeline Litigation, supra note 2.

[10] See id.

[11] See id.

[12] See Chittam Thakore, Understanding the BPCIA Litigation Pathway to Avoid Expensive, Incurable Mistakes, IPWatchdog, Inc. (Nov. 15, 2016), https://ipwatchdog.com/2016/11/15/bpcia-litigation-pathway-avoid-expensive-incurable-mistakes/.

[13] 582 U.S. 1 (2017).

[14] See Sandazo Inc. v. Amgen Inc., 582 U.S. 1, 14 (2017).

[15] See Erika Hanson, Biosimilars, Shall We Do the Patent Dance?, S.J. Quinney C. of L. (Jan. 24, 2018), https://www.law.utah.edu/news-articles/biosimilars-shall-we-do-the-patent-dance/.

[16] See id.

[17] See David Turbert, What is Eylea?, Am. Acad. of Ophthalmology (Jun. 25, 2026) https://www.aao.org/eye-health/drugs/what-is-eylea.

[18] See Kevin DeJong et. al, Amgen Fires Back with Counterclaims in Aflibercept BPCIA Litigation, Big Molecule Watch (Sep. 24, 2025), https://www.bigmoleculewatch.com/2025/09/24/amgen-fires-back-with-counterclaims-in-aflibercept-bpcia-litigation/.

[19] See id.

[20] See id.

[21] See id.

[22] See id.

[23] See Tony Hagen, BIO Attorneys Discuss the BPCIA Patent Dance, MJH Life Scis. (Sep. 15, 2021), https://www.centerforbiosimilars.com/view/bio-attorneys-discuss-the-bpcia-patent-dance.

[24] See id.

[25] See Review and Approval, U.S. Food and Drug Admin. (Dec. 13, 2022), https://www.fda.gov/drugs/biosimilars/review-and-approval.