Amgen Inc. v. Samsung Bioepis Co., Ltd.

Amgen Inc., a major American multinational biopharmaceutical company, initiated this patent infringement lawsuit against Samsung Bioepis Co., Ltd., a South Korean biopharmaceutical company specializing in biosimilar drug development. Amgen focuses on discovering, developing, manufacturing, and delivering innovative human therapeutics for serious illnesses, including bone diseases, and markets the blockbuster drugs Prolia® and Xgeva® (denosumab). Samsung Bioepis sought to enter the U.S. market with its denosumab biosimilar products, OSPOMYV™ and XBRYK™ (denosumab-dssb), which reference Amgen's Prolia® (for osteoporosis) and Xgeva® (for cancer-related bone loss). The core of the dispute revolved around Samsung Bioepis's Abbreviated Biologics License Application (aBLA) filing with the FDA, which, under the Biologics Price Competition and Innovation Act (BPCIA), constituted a technical act of infringement.

The litigation, captioned Amgen Inc. v. Samsung Bioepis Co., Ltd., case number 1:24-cv-08417-CPO-EAP, was filed in the U.S. District Court for the District of New Jersey before Judge Christine P. O'Hearn and Magistrate Judge Elizabeth A. Pascal. Amgen initially asserted 34 U.S. patents, with 21 ultimately specified in the Consent Judgment, covering aspects such as the denosumab antibody composition (e.g., US7364736B2), pharmaceutical formulations, and methods of manufacturing and purification. Denosumab is a human monoclonal antibody that targets RANK Ligand (RANKL) to inhibit osteoclast formation and bone resorption, making it effective in treating osteoporosis and bone metastases. The District of New Jersey is a prominent venue for pharmaceutical patent litigation, known for its judges' expertise in handling complex BPCIA and Hatch-Waxman disputes, and this case was part of a larger multidistrict litigation (MDL) concerning denosumab biosimilars.

This case is notable as part of a significant wave of BPCIA challenges surrounding denosumab, a biologic with combined annual U.S. sales exceeding $5 billion for Amgen's reference products. The entry of biosimilars is expected to foster competition and potentially reduce healthcare costs for these important bone-health therapies. The litigation concluded on January 22, 2026, with a Consent Order and Judgment, entered by stipulation of both parties. For the purposes of this action, Samsung Bioepis agreed that the asserted claims of all 21 patents were valid, enforceable, and infringed by its denosumab biosimilar products. This settlement with Samsung Bioepis was one of several such agreements Amgen reached with biosimilar developers vying to enter the denosumab market. Notably, there have been no Patent Trial and Appeal Board (PTAB) inter partes reviews (IPRs) filed against Amgen's denosumab patents, which is unusual for biosimilar litigations and may be attributed to many of the asserted patents being manufacturing-related, which are less frequently challenged in IPRs.

The patent infringement litigation of Amgen Inc. v. Samsung Bioepis Co., Ltd., Case No. 1:24-cv-08417-CPO-EAP, in the District of New Jersey, concluded with a Consent Order and Judgment.

Key Legal Developments and Outcome:

1. Filing & Initial Pleadings (2024-08-12)
Amgen Inc. and Amgen Manufacturing Limited LLC ("Amgen") filed a complaint for patent infringement against Samsung Bioepis Co., Ltd. ("Bioepis") and Samsung Biologics Co., Ltd. ("Biologics") (collectively, "Samsung") on August 12, 2024. The action was brought under the Biologics Price Competition and Innovation Act (BPCIA) and involved 34 asserted patents related to Samsung's denosumab biosimilar products, OSPOMYV™ (denosumab-dssb) and XBRYK™ (denosumab-dssb), which reference Amgen's PROLIA® and XGEVA® products. The complaint detailed alleged failures by Samsung to comply with BPCIA statutory obligations regarding the production of its BLA materials.

2. Pre-trial Motions of Substance

• Multidistrict Litigation (MDL) Transfer (2025-02-06): On February 6, 2025, the Judicial Panel on Multidistrict Litigation centralized several "denosumab patent litigation" cases, including Amgen Inc. v. Samsung Bioepis Co., Ltd., into MDL No. 3138 in the District of New Jersey, assigned to the Honorable Christine P. O'Hearn. The panel noted that Samsung Bioepis did not respond to the motion for centralization. This centralization was intended to streamline pretrial proceedings due to common questions of fact regarding Amgen's patents covering Prolia® and XGEVA® and the defendants' biosimilar products.

3. Discovery Milestones (Scheduling Order - 2024-12-19)
A scheduling order filed on December 19, 2024, outlined several discovery milestones:

• Samsung Biologics was given until February 13, 2025, to submit a pre-motion conference letter seeking leave to file a motion to dismiss on jurisdictional grounds.
• Fact discovery was to be completed by December 15, 2025.
• By December 23, 2024, Plaintiffs were to substantially complete production of their BLA and associated regulatory filings, and Defendants were to substantially complete production of documents requested during the BPCIA exchange, including cell culture media composition and samples.
• Amgen was to narrow its asserted claims and infringement contentions to no more than twelve patents by August 21, 2025, and further narrow to no more than five patents by April 30, 2026.
• Samsung was to narrow its invalidity theories to no more than five per claim by September 4, 2025, and to no more than three per claim by May 14, 2026.

4. Settlement and Final Disposition (2025-09-05 & 2026-01-22)
On September 5, 2025, the U.S. District Court for the District of New Jersey entered a Consent Order and Judgment, resolving the litigation. This followed a Confidential Settlement Agreement executed between Amgen and Samsung one day prior. While the existing case summary indicates a termination date of January 22, 2026, the Consent Order and Judgment was entered on September 5, 2025. For the purposes of this action, Samsung agreed that 21 of the asserted patents, including US7364736B2, were "valid, enforceable, and infringed" by Samsung's denosumab biosimilar products. All other claims and counterclaims were dismissed with prejudice. The specific terms of the Confidential Settlement Agreement were not publicly disclosed. Samsung's biosimilars, OSPOMYV™ and XBRYK™, received FDA approval on February 13, 2025.

5. Parallel PTAB IPR/PGR Proceedings
While a general search for PTAB cases involving Samsung Bioepis yielded a list of cases, no specific IPR or PGR proceedings for patents US7364736 or US7364736B2 directly related to this Amgen litigation were identified in the provided search results. The court's MDL transfer order did mention that some defendants argued certain overlapping patents were expired or would soon expire, and Amgen might seek damages for past infringement after patent expiration, but this does not specifically point to IPRs or PGRs on the patents at issue in this specific case.

There is no information in the provided search results about specific answers, counterclaims beyond a general dismissal of all other claims and counterclaims with prejudice, pre-trial motions to dismiss or for summary judgment other than the MDL transfer, claim construction (Markman) outcomes, or trial events. The case settled before reaching those later stages.

Counsel of Record for Plaintiff Amgen Inc.

In the patent infringement case Amgen Inc. v. Samsung Bioepis Co., Ltd. (1:24-cv-08417-CPO-EAP, District of New Jersey), the following attorneys are identified as representing the plaintiff, Amgen Inc., and Amgen Manufacturing Limited LLC:

Walsh Pizzi O'Reilly Falanga LLP (Newark, New Jersey)

• Liza M. Walsh

  • Role: Likely local counsel. Ms. Walsh is a founding partner of Walsh Pizzi O'Reilly Falanga LLP and is listed as an attorney for Amgen on the initial complaint.
  • Firm Office: Newark, New Jersey.
  • Experience: Ms. Walsh is a highly experienced litigator with over 30 years in federal and complex commercial litigation, emphasizing intellectual property, antitrust, and class action defense. She has defended major pharmaceutical companies in significant patent litigation and has been recognized in "Best Lawyers in America" for Patent Law. She also led a litigation practice named "Intellectual Property Litigation Group of the Year" by the New Jersey Law Journal.

• Marc D. Haefner

  • Role: Likely local counsel. Mr. Haefner is a partner at Walsh Pizzi O'Reilly Falanga LLP and is listed as an attorney for Amgen on the initial complaint.
  • Firm Office: Newark, New Jersey.
  • Experience: Mr. Haefner's intellectual property practice focuses primarily on trademark, copyright infringement, and trade secret litigation in federal court, alongside complex commercial litigation. His public profile does not specifically detail extensive experience in pharmaceutical patent litigation or biosimilar cases.

• Jessica K. Formichella

  • Role: Likely local counsel. Ms. Formichella is an associate at Walsh Pizzi O'Reilly Falanga LLP and is listed as an attorney for Amgen on the initial complaint.
  • Firm Office: Newark, New Jersey.
  • Experience: Ms. Formichella focuses her practice on state and federal commercial litigation, including intellectual property matters. She is recognized in "Best Lawyers: Ones to Watch® in America 2026" for her work in "Litigation - Patent". She previously served as a Law Clerk to judges in the U.S. District Court for the District of New Jersey and the Superior Court of New Jersey, Appellate Division.

Lead Counsel and In-House Counsel:

While Amgen Inc. frequently retains Finnegan, Henderson, Farabow, Garrett & Dunner, LLP for its biologics and biosimilar patent litigation, and employs in-house intellectual property counsel, the available search results for this specific case (1:24-cv-08417-CPO-EAP) do not explicitly identify any attorneys from Finnegan or specific Amgen in-house counsel who formally entered an appearance on the docket. The initial complaint only lists attorneys from Walsh Pizzi O'Reilly Falanga LLP. Without direct access to the full docket entries detailing all appearances, it cannot be definitively stated whether other outside lead counsel or in-house counsel formally appeared in this particular terminated case.

The following counsel represented the defendant(s), Samsung Bioepis Co., Ltd. and Samsung Biologics Co., Ltd., in this patent infringement case:

Counsel for Samsung Bioepis Co., Ltd. and Samsung Biologics Co., Ltd.:

• Robert Cerwinski (Attorney for Defendant Samsung Bioepis Co., Ltd.)
  • Firm: Gemini Law LLP
  • Office Location: New York, NY
  • Relevant Experience: Cerwinski is listed as an attorney for Samsung Bioepis Co., Ltd. in other MDL patent litigation cases, such as the Aflibercept Patent Litigation.

While no specific New Jersey local counsel was identified in the provided search results for this particular case, it is common practice in federal court for out-of-state firms to associate with local counsel.

It is worth noting that Samsung Bioepis has also engaged other firms for patent litigation in different jurisdictions and contexts. For example, Simmons & Simmons in the Netherlands and UK have represented Samsung Bioepis in European patent disputes, and Quinn Emanuel Urquhart & Sullivan, LLP has represented Samsung Bioepis in PTAB proceedings. Additionally, Samsung Bioepis recently hired Chae Joo-yup, a legal expert with extensive experience in the bio industry, as head of its legal division, with an expected key role in overseas patent litigation.