1:26-cv-00857
MyoKardia Inc v. Zenara Pharma Pvt Ltd
I. Executive Summary and Procedural Information
Parties & Counsel:
- Plaintiff: MyoKardia, Inc. (Delaware) and Bristol-Myers Squibb Company (Delaware)
- Defendant: Zenara Pharma Private Limited (India) and Biophore India Pharmaceuticals Private Limited (India)
- Plaintiff's Counsel: Morris, Nichols, Arsht & Tunnell LLP
Case Identification: MyoKardia, Inc. v. Zenara Pharma Private Limited, 1:26-cv-00857, D. Del., 07/14/2026
Venue Allegations: Venue is alleged to be proper as Defendants are corporations organized under the laws of India and subject to personal jurisdiction in the district. The complaint also notes that Defendant Zenara represented it does not object to venue in the district for this action.
Core Dispute: Plaintiffs allege that Defendants' submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Plaintiffs' Camzyos® (mavacamten) capsules constitutes an act of infringement of two patents covering the mavacamten compound and its method of use.
Technical Context: The technology involves pyrimidinedione compounds, specifically the cardiac myosin inhibitor mavacamten, for the treatment of obstructive hypertrophic cardiomyopathy, a genetic heart muscle disease.
Key Procedural History: This action arises under the Hatch-Waxman Act following Defendants' notification to Plaintiffs of their ANDA filing. The complaint states that Defendants filed certifications with the FDA asserting that the patents-in-suit are invalid, unenforceable, and/or will not be infringed by the proposed generic product.
Case Timeline
| Date | Event |
|---|---|
| 2013-06-21 | Priority Date for '883 and RE'050 Patents |
| 2017-03-07 | U.S. Patent No. 9,585,883 Issues |
| 2024-07-23 | U.S. Reissue Patent No. 50,050 Issues |
| 2026-06-04 | Zenara Pharma sends Notice Letter regarding its ANDA filing |
| 2026-06-05 | Plaintiffs receive Zenara's Notice Letter |
| 2026-06-25 | Zenara represents non-objection to jurisdiction and venue in Delaware |
| 2026-07-14 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Reissue Patent No. 50,050 (the "RE'050 Patent")
- Patent Identification: U.S. Reissue Patent No. 50,050, entitled "Pyrimidinedione Compounds," issued July 23, 2024 Compl. ¶2 Compl. ¶31
The Invention Explained
- Problem Addressed: The shared patent specification describes genetic hypertrophic cardiomyopathy (HCM) as a highly penetrant myocardial disease for which existing medical therapies are limited to treating symptoms and do not address the underlying cause of the disease-disruptions in the function of the sarcomere, the heart's contractile unit '883 Patent, col. 1:21-2:28
- The Patented Solution: The invention provides a class of pyrimidinedione compounds, including mavacamten, that act as novel therapeutic agents '883 Patent, abstract These compounds are designed to reduce excess contractility and promote cardiac relaxation by stabilizing a specific conformation of beta cardiac myosin, thereby reducing the number of myosin molecules participating in the "powerstroke" of muscle contraction '883 Patent, col. 3:25-44
- Technical Importance: These compounds represent a targeted therapy that addresses the fundamental hypercontractility of the sarcomere in HCM, a departure from previous therapies that only managed symptoms '883 Patent, col. 2:5-13
Key Claims at a Glance
- The complaint asserts at least claim 20 of the RE'050 Patent Compl. ¶34 Compl. ¶38 Compl. ¶42
- The complaint alleges that the RE'050 Patent claims recite, inter alia, a series of specifically defined compounds, including mavacamten Compl. ¶33 The full text of the asserted claims is not provided in the complaint.
U.S. Patent No. 9,585,883 (the "'883 Patent")
- Patent Identification: U.S. Patent No. 9,585,883, entitled "Pyrimidinedione Compounds," issued March 7, 2017 Compl. ¶51 '883 Patent, p. 1
The Invention Explained
The technology is as described above for the RE'050 Patent, as they share a common specification.
Key Claims at a Glance
- The complaint asserts at least claim 18, which is a dependent claim '883 Patent, col. 10:55-58, depending from independent claim 15 '883 Patent, col. 10:44-48
- The essential elements of independent claim 15 are:
- A method of treating hypertrophic cardiomyopathy (HCM),
- comprising administering to a subject in need thereof an effective amount
- of a compound of claim 1 or a pharmaceutically acceptable salt thereof.
- Claim 18 narrows the compound to "(S)-3-isopropyl-6-((1-phenylethyl)amino)pyrimidine-2,4(1H,3H)-dione," which is mavacamten, or a pharmaceutically acceptable salt thereof '883 Patent, col. 10:55-58
III. The Accused Instrumentality
Product Identification: The accused instrumentality is "Zenara's ANDA Product," which is a generic version of Plaintiffs' Camzyos® (mavacamten) capsules intended for marketing in 2.5 mg, 5 mg, 10 mg, and 15 mg dosages Compl. ¶2 Compl. ¶29
Functionality and Market Context: The accused product contains the active ingredient mavacamten, which is a cardiac myosin inhibitor used to treat adults with obstructive hypertrophic cardiomyopathy Compl. ¶28 The complaint alleges that Defendants have sought FDA approval to manufacture, use, and sell this generic product in the U.S. market prior to the expiration of the patents-in-suit Compl. ¶3 The infringement action was triggered by Defendants' submission of an Abbreviated New Drug Application ("ANDA") to the FDA Compl. ¶2
IV. Analysis of Infringement Allegations
The complaint does not provide sufficient detail to construct a claim chart for the RE'050 Patent. The infringement allegation is a statutory act of infringement under 35 U.S.C. § 271(e)(2)(A), based on the submission of an ANDA for a drug product where the product itself (mavacamten) is allegedly covered by claim 20 of the RE'050 Patent Compl. ¶33 Compl. ¶38 Compl. ¶40
'883 Patent Infringement Allegations
| Claim Element (from Independent Claim 15, as narrowed by Claim 18) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of treating hypertrophic cardiomyopathy (HCM), | The use of Zenara's ANDA Product will be in accordance with its proposed labeling, which will direct its administration for the treatment of obstructive hypertrophic cardiomyopathy. | ¶28; ¶59 | col. 2:29-34 |
| comprising administering to a subject in need thereof an effective amount | Zenara's proposed labeling will direct the administration of an effective amount of the product (offered in 2.5 mg, 5 mg, 10 mg, and 15 mg capsules) to subjects with the indicated condition. | ¶2; ¶59 | col. 18:65-67 |
| of (S)-3-isopropyl-6-((1-phenylethyl)amino)pyrimidine-2,4(1H,3H)-dione [mavacamten] or a pharmaceutically acceptable salt thereof. | Zenara's ANDA Product is a generic version of Camzyos® and contains the active ingredient mavacamten. | ¶28; ¶29 | col. 9:16-19 |
- Identified Points of Contention:
- Infringement Scope: For the RE'050 Patent, which claims the mavacamten compound, infringement appears to be a direct consequence of the ANDA filing for a product containing that compound. The central dispute will likely focus on the validity and/or enforceability of the patent claims, as asserted by Defendants in their Paragraph IV certification Compl. ¶36
- Inducement: For the '883 Patent, a method of use claim, the key legal question will be whether Zenara's proposed product labeling provides instructions that encourage, recommend, or promote an infringing use, thereby satisfying the requirements for induced infringement. The analysis will center on the content of the proposed label Compl. ¶59 Compl. ¶63
No probative visual evidence provided in complaint.
V. Key Claim Terms for Construction
The complaint does not provide sufficient detail for a comprehensive analysis of claim construction. However, based on the asserted claims and the nature of the technology, the following term may become a focus.
The Term: "effective amount" (from claim 15 of the '883 Patent)
Context and Importance: This term is central to the scope of the method claim. While infringement in an ANDA case is often determined by the proposed label mirroring the innovator's, any ambiguity in what constitutes an "effective amount" could be a point of contention, particularly if Defendants were to argue that the patent fails to teach what amount is effective, raising an indefiniteness challenge under 35 U.S.C. § 112.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides broad dosage ranges, such as "about 0.001 to 100 mg per kg patient body weight per day" ('883 Patent, col. 18:66-67) and tablet formulations containing "1.0 to 1000 milligrams of the active ingredient" '883 Patent, col. 19:8-10 This language may support a broad construction encompassing a wide range of doses.
- Evidence for a Narrower Interpretation: A party seeking a narrower construction might argue the term should be limited to dosages demonstrated to be effective in the patent's own examples, such as the in vitro IC50 values from the Myosin Inhibition Assay '883 Patent, Example 73, col. 27 However, the absence of specific human clinical trial data in the patent may complicate such an argument.
VI. Other Allegations
Indirect Infringement: The complaint alleges both active inducement and contributory infringement for both patents-in-suit Compl. ¶46 Compl. ¶65 For the '883 method patent, the inducement allegation is based on the claim that Zenara's proposed labeling will direct medical professionals and patients to use the ANDA product in an infringing manner Compl. ¶59 Compl. ¶63 The contributory infringement allegation is based on the assertion that Zenara's product is not suitable for substantial non-infringing use Compl. ¶39 Compl. ¶60
Willful Infringement: The complaint does not use the word "willful," but it does allege that Defendants have knowledge of the patents and have "continued to assert its intent to manufacture, offer for sale, sell, distribute, and/or import" the accused product Compl. ¶43 Compl. ¶64 The complaint seeks a declaration that the case is "exceptional" and an award of attorneys' fees under 35 U.S.C. § 285 Prayer ¶i This allegation is predicated on post-notice conduct, as knowledge is established by the notice letter sent by Defendants Compl. ¶35 Compl. ¶55
VII. Analyst's Conclusion: Key Questions for the Case
A primary issue will be one of validity: Given that Zenara's ANDA product contains the mavacamten compound for use in treating HCM, infringement of the asserted claims appears likely if the claims are valid. The case will therefore likely center on Defendants' asserted defenses that the patents are invalid or unenforceable, as raised in their Paragraph IV certifications.
A second key question will be one of induced infringement: For the '883 method-of-use patent, the court will need to determine if the language in Zenara's proposed product label provides sufficient instruction and encouragement to direct or cause physicians and patients to practice the patented method of treatment, thereby making Zenara liable for inducing infringement.