BioMarin Pharmaceutical Inc v. Zydus Lifesciences Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: BioMarin Pharmaceutical Inc. (Delaware)
  • Defendant: Zydus Lifesciences Limited (India); Zydus Lifesciences Global FZE (Dubai); Zydus Pharmaceuticals (USA) Inc. (New Jersey)
  • Plaintiff’s Counsel: FBT Gibbons LLP
• Case Identification: 2:26-cv-01005, D.N.J., 02/02/2026
• Venue Allegations: Venue is alleged to be proper as to the foreign defendants because they may be sued in any judicial district, and as to the domestic defendant because it is organized under the laws of New Jersey and has a regular and established place of business in the state.
• Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) for a generic version of the drug VOXZOGO® constitutes an act of patent infringement under the Hatch-Waxman Act.
• Technical Context: The technology concerns methods of using C-Type Natriuretic Peptide (CNP) variants to treat skeletal dysplasias, such as achondroplasia (the most common form of dwarfism), in very young children.
• Key Procedural History: The lawsuit was triggered by a notice letter dated January 5, 2026, in which Zydus informed BioMarin of its ANDA filing containing a Paragraph IV certification against the patent-in-suit. This certification asserts that Zydus believes the patent is invalid, unenforceable, or will not be infringed by the generic product. The complaint was filed within the 45-day statutory window, which triggers an automatic 30-month stay of FDA approval for Zydus's ANDA.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 12,233,106 - "Use of C-Type Natriuretic Peptide Variants to Treat Skeletal Dysplasia in Children"

• Patent Identification: U.S. Patent No. 12,233,106, "Use of C-Type Natriuretic Peptide Variants to Treat Skeletal Dysplasia in Children", issued February 25, 2025.

The Invention Explained

• Problem Addressed: The patent's background section explains that while C-type natriuretic peptide (CNP) can counteract the genetic mutations that cause skeletal dysplasias like achondroplasia, its therapeutic use is severely limited by a very short plasma half-life of only 2.6 minutes in humans ’106 Patent, col. 10:20-25
• The Patented Solution: The invention is a method for treating skeletal dysplasia specifically in children from birth to about two years of age by administering a CNP variant ’106 Patent, Abstract The specification describes how CNP variants that agonize the NPR-B receptor can inhibit the overactive FGFR-3 pathway responsible for abnormal cartilage formation, thereby promoting bone growth in this young patient population ’106 Patent, col. 9:55-10:11
• Technical Importance: The development of a CNP variant with a longer in-vivo serum half-life is described as important for creating a "sustainable therapeutic strategy" for conditions like achondroplasia ’106 Patent, col. 10:31-33

Key Claims at a Glance

• The complaint asserts infringement of one or more claims, including independent claim 1 (’106 Patent, Compl. ¶50).
• The essential elements of independent claim 1 are:
  • A method of treating skeletal dysplasia
  • in a subject about 0 month to about 2 years old
  • comprising administering to the subject a composition comprising a C-type natriuretic peptide (CNP) variant
  • in an amount effective to treat the skeletal dysplasia
  • wherein the CNP variant is selected from a specific group of peptide sequences.
• The complaint notes that Defendant’s notice letter failed to contest infringement of claims 1-14 and reserves the right to assert infringement of claims beyond claim 1 Compl. ¶¶ 51, 54

III. The Accused Instrumentality

Product Identification

The "Zydus ANDA Product," identified as a purported generic version of VOXZOGO® (vosoritide for injection) in 0.4 mg/vial, 0.56 mg/vial, and 1.2 mg/vial dosages Compl. ¶7

Functionality and Market Context

• The Zydus ANDA Product is a vosoritide injection intended "to treat skeletal dysplasia in children from birth to about 2 years of age" Compl. ¶¶ 46, 50 This intended use, as described in the complaint, directly corresponds to the method claimed in the ’106 patent.
• The complaint characterizes the branded drug, VOXZOGO®, as a "groundbreaking innovation" and the first drug approved in the United States for the treatment of achondroplasia Compl. ¶37 The Zydus ANDA Product seeks to compete as a generic equivalent in this market Compl. ¶1

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

'106 Patent Infringement Allegations

• Identified Points of Contention:
  • Evidentiary Question: The complaint's infringement theory is based on the "intended use" of the Zydus ANDA Product Compl. ¶50 A key question for the court will be what specific instructions and indications are included in the proposed product labeling submitted with Zydus's ANDA, and whether that label induces medical professionals and patients to perform the patented method.
  • Legal Question: The complaint alleges that by failing to provide a detailed claim-by-claim analysis for non-infringement in its Paragraph IV notice letter, Zydus has "conceded infringement" of the ’106 patent Compl. ¶51 This raises the question of whether Zydus has waived its right to contest infringement, which could shift the case's primary focus from infringement to the patent's validity.

V. Key Claim Terms for Construction

• The Term: "a subject about 0 month to about 2 years old"

• Context and Importance: This term defines the specific patient population and is a critical limitation of the method claim. The infringement analysis for inducement will hinge on whether the defendant's proposed drug label directs use for this particular age group.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The use of the word "about" suggests the term is not rigidly fixed and may encompass patients slightly outside the 0-to-24-month window. The specification also discusses treating children between 2 and 5 years old, which could be used to argue the inventors did not intend a strict cutoff at 2 years ’106 Patent, col. 10:49-54
  • Evidence for a Narrower Interpretation: Claim 1 explicitly recites "about 0 month to about 2 years old," and this language is distinct from other claims or disclosures directed to older children. The patent's clinical trial data is presented in cohorts that include "Ages 0 to <6 months" and "Ages 6 to <24 months," which may support an interpretation that the invention is specifically focused on this infant and toddler population ’106 Patent, Fig. 2

• The Term: "skeletal dysplasia"

• Context and Importance: This term defines the medical condition being treated. Its construction is central to defining the scope of the patented method. Practitioners may focus on this term to determine if the patent covers a broad category of diseases or is implicitly limited to the specific embodiment of achondroplasia.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification provides a long, non-exhaustive list of conditions considered to be skeletal dysplasias, including hypochondroplasia, thanatophoric dysplasia, and osteogenesis imperfecta, among many others ’106 Patent, col. 10:27-48 This suggests the term should be given a broad meaning.
  • Evidence for a Narrower Interpretation: The patent's background, summary, and detailed examples focus almost exclusively on achondroplasia as the primary disease of interest ’106 Patent, col. 9:48-54; Example 1, col. 39:27 A party could argue that the invention is functionally limited to what was actually demonstrated.

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement under 35 U.S.C. § 271(b), stating that upon FDA approval, Zydus will knowingly and intentionally encourage direct infringement by healthcare professionals and caregivers Compl. ¶55 The basis for this allegation is the product labeling that will allegedly instruct users to administer the Zydus ANDA Product in a manner that performs the steps of the patented method Compl. ¶55
• Willful Infringement: The complaint alleges willful and deliberate induced infringement, seeking a corresponding judgment Compl., Prayer for Relief ¶g The basis for pre-suit knowledge of the patent is Zydus's act of sending a Paragraph IV notice letter specifically directed to the ’106 patent Compl. ¶53

VII. Analyst’s Conclusion: Key Questions for the Case

• A primary issue will be one of induced infringement: does the proposed product label for the Zydus ANDA Product contain specific instructions that will inevitably lead medical professionals and caregivers to administer the generic drug to the claimed patient population ("about 0 month to about 2 years old") for the claimed indication ("skeletal dysplasia"), thereby satisfying the requirements for inducement?
• A second core issue will be one of legal strategy and waiver: the complaint alleges that Zydus "conceded infringement" by failing to provide a detailed non-infringement argument in its statutory notice letter. A key question for the court will be the legal effect of this alleged omission, which could potentially preclude Zydus from contesting infringement and shift the central dispute of the case entirely to the validity of the ’106 patent.