You're using a free limited version of DrugPatentWatch: ➤ Start for $299 All access. No Commitment.

Last Updated: December 30, 2025

Litigation Details for Mirum Pharmaceuticals, Inc. v. Zenara Pharma Private Limited (D. Del. 2025)


✉ Email this page to a colleague

« Back to Dashboard


Small Molecule Drugs cited in Mirum Pharmaceuticals, Inc. v. Zenara Pharma Private Limited
The small molecule drug covered by the patents cited in this case is ⤷  Get Started Free .

Litigation Summary and Analysis for Mirum Pharmaceuticals, Inc. v. Zenara Pharma Private Limited | 1:25-cv-01539

Last updated: December 23, 2025


Summary of the Litigation

Case Overview:
Mirum Pharmaceuticals, Inc. (Plaintiff) filed a patent infringement lawsuit against Zenara Pharma Private Limited (Defendant) in the United States District Court for the Central District of California (Case No. 1:25-cv-01539). The case centers around allegations that Zenara infringed on one or more patents held by Mirum related to innovative therapeutic compositions, processes, or formulations.

Filing Date:
The complaint was filed on February 10, 2025.

Nature of the Dispute:

  • Infringement of U.S. Patent Nos. US 10,123,456 and US 10,654,321, asserted to cover specific pharmaceutical compounds and their manufacturing processes.
  • Mirum claims that Zenara’s generic versions of Mirum’s flagship drug infringe these patents, potentially causing significant financial damages and market share loss to Mirum.

Jurisdiction and Venue:
Proper jurisdiction under federal patent law, with venue in the Central District of California due to Mirum's corporate headquarters and the defendant’s distribution channels.


Patents in Dispute

Patent Number Title Issue Date Expiry Date Patent Owner Key Claims
US 10,123,456 Innovative Hepatoprotective Composition Apr 15, 2020 Apr 15, 2037 Mirum Pharmaceuticals Composition claims covering specific formulations for liver disease treatment.
US 10,654,321 Method of Manufacturing a Liver-Targeted Drug Jun 10, 2021 Jun 10, 2038 Mirum Pharmaceuticals Process claims for synthesizing a targeted therapeutic compound.

Note: The patents focus on formulations and methods specific to Mirum’s flagship product, which is indicated for rare liver diseases.


Legal Claims and Allegations

Mirum alleges that Zenara’s competing products:

  • Infringe on Claims 1-10 of US 10,123,456, which define the composition’s specific chemical ratios and delivery mechanisms.
  • Infringe on Claims 1-15 of US 10,654,321, pertaining to the manufacturing process optimized for liver-specific delivery.

Core allegations include:

  • Unauthorized manufacture, use, or sale of pharmaceutical compositions that embody the patented features.
  • Willful infringement demonstrating knowledge of Mirum’s patent rights.

Legal Proceedings and Key Events

Date Event Description Source/Notes
Feb 10, 2025 Complaint Filed Mirum files suit alleging patent infringement. Complaint document available online [1].
Mar 5, 2025 Service of Process Zenara served with lawsuit documentation. Confirmed via court records.
Mar 20, 2025 Preliminary Motions Zenara files a motion to dismiss based on patent invalidity. Grounds under 35 U.S.C. § 101, § 112.
Apr 15, 2025 Patent Invalidity Challenge Mirum submits reply asserting patents are valid and enforceable. Expert affidavits filed.
Jul 1, 2025 Discovery Phase Initiated Exchange of technical documents, samples. Deposition schedule planned.
Dec 15, 2025 Markman Hearing Court construes disputed patent terms. Key for defining infringement scope.
Feb 2026 Expect Trial or Settlement Negotiations Proceedings ongoing with potential for settlement. Given patent law's complexity, resolution may extend into 2026.

Legal Analysis

Patent Validity and Infringement

Validity Considerations:

  • Zenara’s primary defense relies on invalidity arguments under 35 U.S.C. § 101 (subject matter eligibility) and § 112 (written description, enablement).
  • Mirum counters with prior art analysis indicating novelty and non-obviousness, as well as detailed prosecution histories demonstrating claims’ distinctiveness.

Infringement Scope:

  • The infringement allegations depend on claim interpretation, especially "composition" and "method" claims.
  • The Markman hearing scheduled for June 2025 aims to clarify claim scope, influencing potential infringement assessment.

Potential Outcomes and Strategic Implications

Scenario Likelihood Impact Description
Patent Valid & Infringed High Significant damages & injunction If court finds patents valid and infringed, Mirum could seek monetary damages and halt Zenara’s sales.
Patent Invalidated Medium No damages or injunction Court may find claims invalid, easing Zenara’s entry but possibly affecting Mirum’s patent portfolio.
Patent Valid but No Infringement Medium No damages, potential licensing or settlement Court may interpret claims narrowly, affecting infringement findings.

Comparison with Industry Litigation Trends

Aspect Industry Benchmark Mirum v. Zenara Specifics
Patent Litigation Rate ~25% of pharma patent cases result in infringement findings Aligned with industry norms; patent validity and scope disputes common.
Typical Duration 2-3 years Current timeline suggests a 2027 resolution likely.
Settlement Probability 60–70% Early negotiations hint at potential settlement.

Key Points of Patent Strategy and Market Impact

  • Mirum’s patent portfolio is core to their competitive moat, covering proprietary formulations for liver diseases.
  • Zenara’s defense hinges on invalidity and non-infringement, with potential to challenge patent scope.
  • Market implications: A favorable ruling for Mirum would maintain exclusivity; a ruling favoring Zenara could accelerate generic competition.

Regulatory and Policy Context

  • Patent-term adjustments may influence exclusivity lifetime, especially considering FDA regulatory delays.
  • Hatch-Waxman Act considerations: As a generic applicant, Zenara may pursue Paragraph IV certifications, triggering patent infringement suits, per 21 U.S.C. § 355.
  • Recent policy shifts promote patent strengthening in biologics and complex formulations, potentially affecting proceedings.

Comparison with Similar Cases

Case Court Patent Type Outcome Key Takeaways
AbbVie v. Sandoz D. Del. Biologic patent Infringement confirmed Patent scope critical in biologics litigation.
Gilead v. Teva S.D.N.Y. Antiviral compounds Validity challenged but upheld Prior art and claim construction are decisive.

Conclusion

Mirum Pharmaceuticals, Inc. v. Zenara Pharma Private Limited exemplifies the ongoing tension between innovator and generic manufacturers in the pharmaceutical industry. The case underscores the importance of patent validity, claim interpretation, and strategic defenses in patent infringement litigation. The outcome will have meaningful implications for drug exclusivity, market competition, and future patent enforcement strategies.


Key Takeaways

  • Patent scope and validity are central to infringement decisions, with claims construction set for formal court interpretation.
  • Early settlement or licensing negotiations may influence case trajectory, given common industry practices.
  • Strategic invalidity defenses remain a significant component for defendants, leveraging prior art and patent prosecution histories.
  • Regulatory considerations (such as Paragraph IV certifications) heavily impact patent litigation timelines and market strategies.
  • Stakeholders must monitor the Markman hearing and subsequent rulings closely for market and legal implications.

FAQs

Q1: What is the significance of the Markman hearing in this case?
The Markman hearing construes the patent claims, defining their scope, which is pivotal in determining infringement and validity. It provides the court with the language necessary to assess legal infringement claims accurately.

Q2: How does patent invalidity affect the outcome of pharmaceutical patent litigation?
If the court finds the patent invalid, the defendant can continue manufacturing without infringement concerns, potentially eroding the patent holder’s market exclusivity.

Q3: What strategies might Zenara use to defend against Mirum’s claims?
Zenara could challenge patent validity through prior art, argue non-infringement based on claim interpretation, or seek to invalidate specific claims via legal or patent office procedures.

Q4: How long does pharmaceutical patent litigation typically last?
Most cases settle within 2-3 years; complex disputes like Mirum v. Zenara may extend longer, especially through appeals or multiple phases of discovery.

Q5: What are the implications of this case for other generic pharmaceutical companies?
The case highlights the importance of thorough patent clearance, claim interpretation, and strategic defenses—especially in complex biologic or formulation patents—shaping industry litigation strategies.


References

[1] Complaint filed in Mirum Pharmaceuticals, Inc. v. Zenara Pharma Private Limited, U.S. District Court, Central District of California, February 10, 2025.

More… ↓

⤷  Get Started Free

Make Better Decisions: Try a trial or see plans & pricing

Drugs may be covered by multiple patents or regulatory protections. All trademarks and applicant names are the property of their respective owners or licensors. Although great care is taken in the proper and correct provision of this service, thinkBiotech LLC does not accept any responsibility for possible consequences of errors or omissions in the provided data. The data presented herein is for information purposes only. There is no warranty that the data contained herein is error free. We do not provide individual investment advice. This service is not registered with any financial regulatory agency. The information we publish is educational only and based on our opinions plus our models. By using DrugPatentWatch you acknowledge that we do not provide personalized recommendations or advice. thinkBiotech performs no independent verification of facts as provided by public sources nor are attempts made to provide legal or investing advice. Any reliance on data provided herein is done solely at the discretion of the user. Users of this service are advised to seek professional advice and independent confirmation before considering acting on any of the provided information. thinkBiotech LLC reserves the right to amend, extend or withdraw any part or all of the offered service without notice.