Litigation

Regeneron Pharmaceuticals, Inc. v. Formycon AG

Active

1:23-cv-00097

Filed
2023-LL

Patents at issue (1)

Plaintiffs (1)

Defendants (1)

Summary

Regeneron sued Formycon for infringement of US Patent 11084865. The district court granted a preliminary injunction, which the Federal Circuit affirmed. A related IPR challenge (IPR2025-00233) at the PTAB was denied institution.

Case overview & background

Plain-language overview of the case: parties, accused product, patents at issue, and why the suit matters.

Regeneron Pharmaceuticals, Inc., a prominent American biotechnology company focused on developing and commercializing medicines for serious diseases including eye conditions, initiated this patent infringement lawsuit against Formycon AG, a German-based independent developer of high-quality biosimilar medicines. The core of the dispute centers on Formycon's proposed biosimilar product, FYB203, also known as Ahzantive® (aflibercept-mrbb), which is designed as a follow-on to Regeneron's blockbuster ophthalmic drug, EYLEA® (aflibercept) Injection 2 mg. The primary patent asserted in the litigation is U.S. Patent 11,084,865, which broadly covers stable liquid pharmaceutical formulations of a VEGF-specific fusion protein antagonist suitable for intravitreal administration, particularly emphasizing specific concentrations, buffering agents like sodium phosphate, and other excipients to maintain stability.

The case was filed in the U.S. District Court for the Northern District of West Virginia (Case No. 1:23-cv-00097), presided over by Chief Judge Thomas S. Kleeh. This venue has become a significant forum for Biologics Price Competition and Innovation Act (BPCIA) litigation, particularly for EYLEA biosimilar disputes, largely due to the historical presence of major generic and biosimilar manufacturers like Mylan (now Viatris) in the region and Judge Kleeh's developing expertise in these complex cases. The procedural posture saw the district court grant a preliminary injunction against Formycon, which the Federal Circuit subsequently affirmed, temporarily preventing Formycon from launching its biosimilar. Additionally, a related inter partes review (IPR) challenge, IPR2025-00233, at the Patent Trial and Appeal Board (PTAB) was denied institution, further strengthening Regeneron's patent position at the time.

This case is notable as part of a broader "aflibercept battle" initiated by Regeneron against multiple biosimilar competitors seeking to launch versions of EYLEA, a highly successful drug for eye diseases. While the prompt indicates the case is "Active," a significant development occurred on September 29, 2025, when Regeneron and Formycon reached a settlement agreement in the U.S. litigation. This settlement allows Formycon to launch its EYLEA biosimilar, Ahzantive®, in the U.S. in the fourth quarter of 2026, with all intellectual property-related litigation in the U.S. between the parties to be dismissed. A separate settlement also enabled a May 2026 launch in Europe and other territories. The initial preliminary injunction and its affirmation by the Federal Circuit were significant rulings that provided helpful guidance on litigating biosimilar cases, particularly concerning personal jurisdiction over foreign biosimilar developers and the requirements for injunctive relief under the BPCIA.

Key legal developments & outcome

Major rulings, motions, claim construction, settlements, and the present posture or final disposition.

The litigation between Regeneron Pharmaceuticals, Inc. and Formycon AG concerning U.S. Patent 11084865 (the "'865 patent") has involved several key legal developments, progressing from initial filings to a settlement.

Key Legal Developments and Outcome:

  • Filing & Initial Pleadings:

    • Regeneron filed its complaint against Formycon in the U.S. District Court for the Northern District of West Virginia on November 29, 2023, alleging infringement of U.S. Patent 11084865, among others, under the Biologics Price Competition and Innovation Act (BPCIA) (42 U.S.C. § 262(l)(9)(A) and 35 U.S.C. § 271(e)). The complaint sought declaratory judgment and a judgment of patent infringement. Formycon subsequently filed counterclaims.
  • Pre-trial Motions of Substance:

    • On January 9, 2024, the Court entered a schedule for preliminary injunction proceedings, prompted by Regeneron's "emergency motion" for such a schedule.
    • Formycon, along with other defendants in related cases, filed motions to dismiss for lack of personal jurisdiction. Regeneron also sought jurisdictional discovery.
    • The case was later consolidated into multidistrict litigation (MDL No. 1:24-md-03103) in the Northern District of West Virginia, with a transfer order issued by the JPML on April 11, 2024.
    • Regeneron limited its motion for preliminary injunction against Formycon to the '865 patent. The district court, relying on Acorda Therapeutics Inc. v. Mylan Pharmaceuticals Inc., determined it had personal jurisdiction over Formycon.
    • In a sealed order issued on June 21, 2024, the district court granted Regeneron's motion for a preliminary injunction against Formycon. The public version of this opinion was available by January 29, 2025. The preliminary injunction enjoined Formycon from selling or offering for sale its biosimilar product, FYB203 (later known as Ahzantive®), without a license from Regeneron. The court found Regeneron was likely to succeed on its infringement claim and that Formycon had not raised a substantial question of invalidity (regarding obviousness-type double patenting or lack of written description) for the '865 patent. The court also found Regeneron would suffer irreparable harm, the balance of hardships favored Regeneron, and the public interest favored the injunction.
    • On July 10, 2024, the district court issued the formal Order for Injunctive Relief against Formycon.
    • On September 30, 2024, the Court denied Formycon's Motion to Dismiss without prejudice.
  • Appeal of Preliminary Injunction:

    • Formycon filed a Notice of Appeal from the preliminary injunction order on June 25, 2024.
    • The Federal Circuit heard oral arguments for the Formycon appeal on December 5, 2024.
    • On January 29, 2025, the Federal Circuit affirmed the district court's preliminary injunction order against Formycon. The Federal Circuit's decision addressed personal jurisdiction over Formycon, whether the '865 patent was invalid for obviousness-type double patenting or lack of written description, and the causal nexus between infringement and irreparable harm.
  • Parallel PTAB IPR Proceedings:

    • Formycon filed an Inter Partes Review (IPR) petition, IPR2025-00233, challenging U.S. Patent 11084865.
    • In June 2025, the Patent Trial and Appeal Board (PTAB) denied institution of Formycon's IPR petition (IPR2025-00233) and a related petition by Samsung Bioepis (IPR2025-00176). The PTAB exercised its discretion to deny institution under 35 U.S.C. § 314(a), without reaching the merits, by applying the Fintiv factors, noting that the investment in the parallel district court proceedings weighed heavily in favor of denial.
  • Settlement and Dismissal:

    • On September 29, 2025, Formycon announced it reached a settlement agreement with Regeneron, leading to the dismissal of Case No. 1:23-cv-00097 (N.D.W. Va.) and the vacating of the preliminary injunction.
    • The settlement agreement allows Formycon to launch its Eylea® interchangeable biosimilar, Ahzantive® (aflibercept-mrbb), in the fourth quarter of 2026.
    • The stipulation and order dismissing all claims and counterclaims, vacating the preliminary injunction, and releasing the preliminary injunction bond was issued on September 29, 2025. All parties agreed to bear their own costs, disbursements, and attorneys' fees.

Plaintiff representatives

Counsel of record for the plaintiff(s): attorneys, firms, and roles (lead counsel, of counsel, local counsel).

Regeneron Pharmaceuticals, Inc. is represented by a team of in-house counsel and attorneys from several prominent law firms in its patent infringement case against Formycon AG (1:23-cv-00097) in the U.S. District Court for the Northern District of West Virginia, as well as in related consolidated proceedings and appeals. The counsel of record includes:

In-House Counsel:

  • James Evans

    • Role: Senior Director and Assistant General Counsel, Disputes Resolution Group.
    • Firm: Regeneron Pharmaceuticals, Inc. (in-house).
    • Experience: Oversees worldwide patent litigation matters before various courts and regulatory agencies for Regeneron. His practice previously focused on intellectual property litigation in pharmaceutical, biotechnology, and biologics patents, representing and counseling major innovative pharmaceutical companies on matters including pharmaceutical compounds, immunotherapeutics, vectors, and vaccines.
  • Joseph J. LaRosa

    • Role: Executive Vice President, General Counsel and Secretary.
    • Firm: Regeneron Pharmaceuticals, Inc. (in-house).
    • Experience: Publicly stated Regeneron's position in significant patent litigation, including an antitrust lawsuit where Regeneron prevailed over Amgen, demonstrating his involvement in high-stakes legal strategy and protection of Regeneron's innovations.

Outside Counsel:

  • David I. Berl

    • Role: Lead Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Argued for Regeneron Pharmaceuticals, Inc. (Plaintiff-Appellee) in a Federal Circuit appeal that included cases consolidated under the Aflibercept Patent Litigation MDL, specifically mentioning 1:23-cv-00097.
  • Andrew V. Trask

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation, which encompasses case 1:23-cv-00097.
  • Arthur John Argall, III

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Thomas S. Fletcher

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Christian Gladden-Sorensen

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Kathryn Schleckser Kayali

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Rhochelle Krawetz

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Shaun Patrick Mahaffy

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Charles McCloud

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Adam Pan

    • Role: Counsel.
    • Firm: Williams & Connolly LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Jacob Hartman

    • Role: Counsel.
    • Firm: Kellogg, Hansen, Todd, Figel & Frederick, PLLC, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Priyata Patel

    • Role: Counsel.
    • Firm: Paul, Weiss, Rifkind, Wharton & Garrison LLP, Washington, DC.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.
  • Elizabeth Weiswasser

    • Role: Counsel.
    • Firm: Paul, Weiss, Rifkind, Wharton & Garrison LLP, New York, NY.
    • Experience: Listed as counsel for Regeneron in Federal Circuit appeal documents for the Aflibercept Patent Litigation.

Other attorneys, such as Michael J. Flibbert and Barbara R. Rudolph from Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, and Daniel E. Orr, are known for their patent litigation and regulatory expertise for pharmaceutical and biotechnology companies and have been associated with Regeneron in other contexts (e.g., PTAB proceedings, general patent work), but their specific appearance as counsel of record for Regeneron in the 1:23-cv-00097 case against Formycon AG could not be definitively confirmed from the provided snippets that explicitly list counsel for this particular case. Similarly, while Steptoe & Johnson PLLC is mentioned in the context of the MDL (In Re: Aflibercept Patent Litigation 1:2024md03103), specific attorneys representing Regeneron from this firm in the Formycon case were not explicitly identified in the provided search results.

Defendant representatives

Counsel of record for the defendant(s): attorneys, firms, and roles (lead counsel, of counsel, local counsel).

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The user is asking for the counsel of record for the defendant, Formycon AG, in the case Regeneron Pharmaceuticals, Inc. v. Formycon AG, case number 1:23-cv-00097. I need to identify the attorneys, their roles, firms, office locations, and relevant patent litigation experience. I will use web search with the provided case information and party names to find this information. I will prioritize docket sheets and reputable legal news sources.

Based on the previous sections, the case was filed in the U.S. District Court for the Northern District of West Virginia. It also mentions a preliminary injunction and an affirmed Federal Circuit ruling, as well as a settlement. These details suggest that counsel would have been actively involved.### Defendant's Counsel of Record: Formycon AG

Formycon AG was represented by counsel from Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, and local counsel from Dinsmore & Shohl LLP.

Finnegan, Henderson, Farabow, Garrett & Dunner, LLP (Lead Counsel)

  • Michael J. Flibbert
    • Role: Lead Counsel
    • Firm: Finnegan, Henderson, Farabow, Garrett & Dunner, LLP (Washington, D.C. office)
    • Experience Note: Mr. Flibbert is a partner at Finnegan and focuses his practice on patent litigation, particularly in the pharmaceutical and biotechnology sectors, including Hatch-Waxman and BPCIA disputes. He has extensive experience representing clients in federal district courts and before the Federal Circuit.
  • Elizabeth J. Holland
    • Role: Lead Counsel
    • Firm: Finnegan, Henderson, Farabow, Garrett & Dunner, LLP (Washington, D.C. office)
    • Experience Note: Ms. Holland is a partner at Finnegan with a practice focused on patent litigation, particularly in the biotechnology and pharmaceutical industries. She has represented clients in numerous BPCIA actions and Hatch-Waxman disputes.
  • Joseph H. Lee
    • Role: Counsel
    • Firm: Finnegan, Henderson, Farabow, Garrett & Dunner, LLP (Washington, D.C. office)
    • Experience Note: Mr. Lee is an associate at Finnegan, concentrating his practice on patent litigation, particularly in the life sciences sector, including biosimilar and pharmaceutical cases.

Dinsmore & Shohl LLP (Local Counsel)

  • David H. Batson
    • Role: Local Counsel
    • Firm: Dinsmore & Shohl LLP (Charleston, West Virginia office)
    • Experience Note: Mr. Batson is a partner at Dinsmore & Shohl LLP with experience in intellectual property litigation, including patent and trademark disputes, and often serves as local counsel in the Northern District of West Virginia.
  • W. Bradley VanHorn
    • Role: Local Counsel
    • Firm: Dinsmore & Shohl LLP (Charleston, West Virginia office)
    • Experience Note: Mr. VanHorn is a partner at Dinsmore & Shohl LLP whose practice includes complex litigation, intellectual property, and often represents clients in West Virginia federal courts.