DCT
2:24-cv-06263
Esperion Therap Inc v. Alkem Laboratories Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Esperion Therapeutics, Inc. (Delaware)
- Defendant: Alkem Laboratories Ltd. (India)
- Plaintiff’s Counsel: Walsh Pizzi Oreilly Falanga LLP
- Case Identification: 2:24-cv-06263, D.N.J., 09/29/2025
- Venue Allegations: Plaintiff alleges venue is proper because Defendant is an Indian corporation not resident in the United States and may be sued in any judicial district. Plaintiff further alleges Defendant has a regular and established place of business in New Jersey through its business contacts, marketing, and sales in the state.
- Core Dispute: Plaintiff alleges that Defendant’s submission of Abbreviated New Drug Applications (ANDAs) to the FDA for generic versions of Plaintiff's cholesterol-lowering drugs, NEXLETOL® and NEXLIZET®, constitutes infringement of seven U.S. patents relating to bempedoic acid compositions, crystalline forms, and methods of use.
- Technical Context: The patents relate to bempedoic acid, an active pharmaceutical ingredient used to lower low-density lipoprotein cholesterol (LDL-C) in adults, addressing the significant market for cardiovascular disease treatments.
- Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendant’s submission of ANDA Nos. 219416 (for generic NEXLETOL®) and 219421 (for generic NEXLIZET®). Defendant provided Paragraph IV certifications asserting that the patents-in-suit are invalid, unenforceable, or will not be infringed by its generic products. This filing is a Second Amended Complaint, following an original complaint filed on May 17, 2024.
Case Timeline
| Date | Event |
|---|---|
| 2015-03-31 | Earliest Priority Date for ’751 and ’816 Patents |
| 2019-06-21 | Earliest Priority Date for ’714, ’511, ’584, ’087, and ’227 Patents |
| 2020-02-21 | FDA Approval of NEXLETOL® New Drug Application |
| 2020-02-26 | FDA Approval of NEXLIZET® New Drug Application |
| 2021-02-09 | U.S. Patent No. 10,912,751 Issues |
| 2023-03-28 | U.S. Patent No. 11,613,511 Issues |
| 2023-09-05 | U.S. Patent No. 11,744,816 Issues |
| 2023-09-19 | U.S. Patent No. 11,760,714 Issues |
| 2024-03-12 | U.S. Patent No. 11,926,584 Issues |
| 2024-03-22 | FDA approves new label for NEXLETOL® |
| 2024-04-05 | Plaintiff receives Defendant’s First NEXLETOL® Notice Letter |
| 2024-04-24 | Plaintiff receives Defendant’s First NEXLIZET® Notice Letter |
| 2024-05-17 | Original Complaint filed by Plaintiff |
| 2024-06-10 | Plaintiff receives Defendant's Second NEXLETOL® and NEXLIZET® Notice Letters |
| 2025-08-26 | U.S. Patent No. 12,398,087 Issues |
| 2025-09-02 | U.S. Patent No. 12,404,227 Issues |
| 2025-09-29 | Second Amended Complaint filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,760,714 - "Methods of Making Bempedoic Acid and Compositions of the Same"
The Invention Explained
- Problem Addressed: The patent's background describes the technical challenge of developing robust, cost-effective, and efficient manufacturing processes for producing active pharmaceutical ingredients (APIs) like bempedoic acid with the high yield and purity required by regulatory agencies for commercial drug products (’714 Patent, col. 1:22-34).
- The Patented Solution: The invention provides methods for synthesizing high-purity bempedoic acid and claims the resulting pharmaceutical compositions, which are defined by a high level of the desired API (bempedoic acid) and a strictly limited amount of a specified impurity (’714 Patent, Abstract; Compl. ¶113). The complaint provides a chemical structure diagram of bempedoic acid, identified as formula (V) in the patent claims (Compl. ¶113).
- Technical Importance: Achieving high purity and controlling specific impurities in an API is critical for ensuring patient safety, drug efficacy, and meeting the stringent standards for FDA approval.
Key Claims at a Glance
- The complaint asserts at least claim 1 (Compl. ¶115).
- Claim 1 is a composition claim with the following essential elements:
- A pharmaceutical composition comprising a pharmaceutical material, which in turn comprises a crystalline form of bempedoic acid (formula V) or its salt.
- The pharmaceutical material contains >98% by weight of the bempedoic acid or its salt.
- The pharmaceutical material contains between 0.0001% and 0.15% of a specified impurity (formula VI).
- The composition includes a pharmaceutically acceptable excipient (Compl. ¶113).
- The complaint does not explicitly reserve the right to assert dependent claims but makes general allegations against the "claims of the '714 Patent" (Compl. ¶114).
U.S. Patent No. 11,613,511 - "Methods of Making Bempedoic Acid and Compositions of the Same"
The Invention Explained
- Problem Addressed: Similar to the ’714 Patent, this patent addresses the need for robust manufacturing processes that produce bempedoic acid with a required purity profile for a commercial drug product (’511 Patent, col. 1:22-34).
- The Patented Solution: This invention claims a specific crystalline form, or polymorph, of bempedoic acid. The solution is a pharmaceutical material containing this specific crystalline form, which is identified by a characteristic pattern of peaks in an X-ray powder diffraction (XRPD) analysis, in addition to specified purity levels (’511 Patent, Abstract; Compl. ¶¶137, 148). The use of a specific, stable crystalline form ensures consistent physical properties like solubility and stability, which are critical for predictable drug performance.
- Technical Importance: Controlling the polymorphic form of an API is crucial in pharmaceutical development, as different crystalline structures can have different physical properties affecting bioavailability and stability.
Key Claims at a Glance
- The complaint asserts at least claim 1 (Compl. ¶139).
- Claim 1 is for a pharmaceutical material with the following essential elements:
- A pharmaceutical material comprising a crystalline form of bempedoic acid (formula V) or its salt.
- The material contains >99.0% by weight of the bempedoic acid or its salt.
- The material contains between 0.0001% and 0.15% of a specified impurity (formula VI).
- The crystalline form exhibits an XRPD pattern with peaks at specific diffraction angles (2θ), including 10.3±0.2, 10.4±0.2, and 17.9±0.2 (Compl. ¶¶137, 148).
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 11,744,816 - "Fixed Dose Combinations and Formulations Comprising ETC1002 and Ezetimibe and Methods of Treating or Reducing the Risk of Cardiovascular Disease"
- Patent Identification: Issued September 5, 2023 (Compl. ¶36).
- Technology Synopsis: The patent addresses cardiovascular disease and high cholesterol (hypercholesterolemia). It claims a method of lowering LDL-C by administering a combination of 180 mg of bempedoic acid and 10 mg of ezetimibe to a subject with familial hypercholesterolemia (’816 Patent, Abstract; Compl. ¶¶159, 180).
- Asserted Claims: Claim 1 (Compl. ¶¶159, 180).
- Accused Features: Alkem’s NEXLIZET® ANDA Product, a fixed-dose combination product, is accused of direct and indirect infringement (Compl. Count VI). Alkem’s NEXLETOL® ANDA Product is accused of indirect infringement based on allegations that its proposed label will instruct co-administration with ezetimibe (Compl. Count V).
U.S. Patent No. 11,926,584 - "Methods of Making Bempedoic Acid and Compositions of the Same"
- Patent Identification: Issued March 12, 2024 (Compl. ¶39).
- Technology Synopsis: The patent claims a method of lowering LDL-C by administering a therapeutically effective amount of a pharmaceutical material comprising a crystalline form of bempedoic acid with a purity greater than 99.0% and a specified impurity level of less than 0.15% (’584 Patent, Claim 1). This patent protects the therapeutic use of the highly purified compositions claimed in related patents.
- Asserted Claims: Claim 1 (Compl. ¶¶198, 214).
- Accused Features: Both the NEXLETOL® and NEXLIZET® ANDA products are accused of indirect infringement, based on allegations that their proposed product labels will instruct administration according to the claimed method (Compl. ¶¶203, 219).
U.S. Patent No. 10,912,751 - "Fixed Dose Combinations and Formulations Comprising ETC1002 and Ezetimibe and Methods of Treating or Reducing the Risk of Cardiovascular Disease"
- Patent Identification: Issued February 9, 2021 (Compl. ¶33).
- Technology Synopsis: This patent claims a method for treating familial hypercholesterolemia by administering a fixed-dose combination of 180 mg bempedoic acid and 10 mg ezetimibe (’751 Patent, Claim 1). This patent is directed at a specific treatment indication for the combination therapy.
- Asserted Claims: Claim 1 (Compl. ¶230).
- Accused Features: The Alkem NEXLIZET® ANDA Product is accused of indirect infringement, with allegations that its proposed package insert will instruct for the claimed method of treating familial hypercholesterolemia (Compl. ¶¶235-237).
U.S. Patent No. 12,398,087 - "Methods of Making Bempedoic Acid and Compositions of the Same"
- Patent Identification: Issued August 26, 2025 (Compl. ¶42).
- Technology Synopsis: The patent claims a pharmaceutical material comprising bempedoic acid with a purity greater than 98% and a specified impurity level between 0.001% and 0.15% (’087 Patent, Claim 1). This patent covers another composition defined by specific purity and impurity ranges.
- Asserted Claims: Claim 1 (Compl. ¶¶246, 258).
- Accused Features: Both the NEXLETOL® and NEXLIZET® ANDA products are accused of infringement on the basis that they will contain the claimed pharmaceutical material (Compl. ¶¶247, 259).
U.S. Patent No. 12,404,227 - "Methods of Making Bempedoic Acid and Compositions of the Same"
- Patent Identification: Issued September 2, 2025 (Compl. ¶45).
- Technology Synopsis: The patent claims a pharmaceutical material comprising bempedoic acid with a purity greater than 99.0% and containing a different specified impurity (formula VIII) at a level between 0.0001% and 0.15% (’227 Patent, Claim 1). This patent further protects the API through claims directed to a distinct impurity profile.
- Asserted Claims: Claim 1 (Compl. ¶¶270, 282).
- Accused Features: Both the NEXLETOL® and NEXLIZET® ANDA products are accused of infringement on the basis that they will contain the claimed pharmaceutical material (Compl. ¶¶271, 283).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are Defendant Alkem’s proposed generic drug products submitted to the FDA under ANDA No. 219416 (the "Alkem NEXLETOL® ANDA Product") and ANDA No. 219421 (the "Alkem NEXLIZET® ANDA Product") (Compl. ¶¶7, 11).
Functionality and Market Context
- The Alkem NEXLETOL® ANDA Product contains bempedoic acid as its active pharmaceutical ingredient (Compl. ¶7). The Alkem NEXLIZET® ANDA Product is a combination product containing bempedoic acid and ezetimibe (Compl. ¶11). The complaint alleges that by submitting its ANDAs, Alkem represented to the FDA that its proposed generic products have the same active ingredient(s), dosage form, and strength as Plaintiff’s NEXLETOL® and NEXLIZET® products and are bioequivalent to them (Compl. ¶¶63, 91). These products are intended to lower LDL-C in adults with cardiovascular disease or primary hyperlipidemia (Compl. ¶¶51, 56). The filing of the ANDAs is an act of infringement under 35 U.S.C. § 271(e)(2) that allows for litigation prior to the commercial launch of the generic products (Compl. ¶¶1, 114, 126).
IV. Analysis of Infringement Allegations
U.S. Patent No. 11,760,714 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a pharmaceutical composition, comprising: a pharmaceutical material comprising a crystalline form of the compound of formula (V), or a pharmaceutically acceptable salt thereof; | The Alkem ANDA products allegedly comprise a crystalline form of bempedoic acid (formula V), as they are represented to be bioequivalent to NEXLETOL® and NEXLIZET®, which are covered by the claim. | ¶¶63, 91, 113 | col. 19:19-22 |
| wherein the pharmaceutical material comprises the compound of formula (V), or a pharmaceutically acceptable salt thereof, in an amount greater than 98% by weight based on the total weight of the pharmaceutical material, | The Alkem ANDA products are alleged to meet this purity limitation by virtue of being generic versions of Plaintiff's products, which are alleged to meet this limitation. | ¶¶53, 63, 91, 113 | col. 19:22-26 |
| and the pharmaceutical material comprises 0.0001% to less than or equal to 0.15% of a compound of formula (VI): | The Alkem ANDA products are alleged to meet this impurity profile limitation by virtue of being generic versions of Plaintiff's products, which are alleged to meet this limitation. | ¶¶53, 63, 91, 113 | col. 19:26-29 |
| and a pharmaceutically acceptable excipient. | As formulated drug products, the Alkem ANDA products will necessarily contain one or more pharmaceutically acceptable excipients. | ¶¶63, 91, 113 | col. 19:33-34 |
U.S. Patent No. 11,613,511 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a pharmaceutical material comprising a crystalline form of the compound of formula (V) or a pharmaceutically acceptable salt thereof; | The Alkem ANDA products allegedly comprise a crystalline form of bempedoic acid (formula V), as they are represented to be bioequivalent to NEXLETOL® and NEXLIZET®. | ¶¶63, 91, 137 | col. 29:6-8 |
| wherein the pharmaceutical material comprises the compound of formula (V), or a pharmaceutically acceptable salt thereof, in an amount greater than 99.0% by weight based on the total weight of the pharmaceutical material, | The Alkem ANDA products are alleged to meet this higher purity limitation by virtue of being generic versions of Plaintiff's products. | ¶¶63, 91, 137 | col. 29:8-12 |
| the pharmaceutical material comprises 0.0001% to less than or equal to 0.15% of a compound of formula (VI): | The Alkem ANDA products are alleged to meet this impurity profile limitation by virtue of being generic versions of Plaintiff's products. | ¶¶63, 91, 137 | col. 29:12-14 |
| and the crystalline form of the compound of formula (V) exhibits an X-ray powder diffraction pattern comprising peaks at the following diffraction angles (2θ): 10.3±0.2, 10.4±0.2, 17.9±0.2, 18.8±0.2, 19.5±0.2, and 20.7±0.2. | The Alkem ANDA products, in seeking to be generic equivalents, are alleged to use the same crystalline polymorph of bempedoic acid as Plaintiff's products, which exhibits the claimed XRPD pattern. | ¶¶63, 91, 137 | col. 29:15-19 |
Identified Points of Contention
- Evidentiary Questions: For the composition patents (’714, ’511, ’087, ’227), the central dispute will likely be factual. The complaint's allegations rely on the premise that Alkem's ANDA products are identical or bioequivalent to the branded drugs. The key question is what evidence will show that Alkem’s actual products meet the specific purity percentages, impurity thresholds, and, for the ’511 Patent, the exact crystalline form defined by the XRPD peaks.
- Technical Questions: A potential point of contention for the ’511 Patent is whether Alkem may have developed a different, non-infringing crystalline polymorph of bempedoic acid that is nonetheless bioequivalent. The infringement analysis will turn on whether Alkem's API exhibits the specific XRPD peaks required by claim 1.
- Scope Questions: For the method of use patents (’816, ’584, ’751), a primary legal question will be whether the language in Alkem’s proposed product labels is sufficient to prove the specific intent required to induce infringement by doctors and patients. For the ’816 Patent asserted against the NEXLETOL® product, the dispute raises the question of whether marketing a single-ingredient drug can be proven to induce its combined use with a separate drug to infringe a combination method claim.
V. Key Claim Terms for Construction
The Term: "pharmaceutical material"
- Context and Importance: This term appears in the composition claims of the ’714, ’511, ’584, ’087, and ’227 patents. Its construction is critical because the claimed purity and impurity percentages are calculated based on the "total weight of the pharmaceutical material." The definition will determine the denominator for that calculation—specifically, whether it includes only the API and its direct process impurities, or also encompasses other substances like stabilizers or processing aids that might be present before final formulation with excipients.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The complaint does not provide specific language from the patent to support a broader interpretation. However, a party could argue that in the context of pharmaceutical manufacturing, a "material" ready for formulation might include more than just the pure API.
- Evidence for a Narrower Interpretation: The ’511 Patent specification states, "As used herein, 'pharmaceutical material' refers to the compound of formula (V), or a pharmaceutically acceptable salt thereof, and any impurities" (’511 Patent, col. 13:62-64). This language suggests a narrow definition limited to the API and its associated impurities, excluding other additives.
The Term: "crystalline form"
- Context and Importance: This term is central to all composition claims, but especially to claim 1 of the ’511 Patent, which defines the invention by a specific set of XRPD peaks. The definition of "crystalline form" and the scope of the phrase "exhibits an X-ray powder diffraction pattern comprising peaks at..." will determine whether minor variations in peak position or the presence of additional peaks in Alkem’s product can avoid infringement. Practitioners may focus on whether Alkem's product uses the same polymorph claimed by Esperion or has developed a different, non-infringing one.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim uses the word "comprising" with respect to the list of peaks, which typically means the list is not exhaustive. An argument could be made that an accused product exhibiting the required peaks infringes, even if it also shows additional peaks.
- Evidence for a Narrower Interpretation: The ’511 Patent specification provides detailed characterization data for a specific crystalline form, including not only XRPD but also DSC and TGA analyses (’511 Patent, col. 12-14, FIGS. 4-6). This focus on a single, well-characterized form could support an interpretation that the claims are limited to that specific polymorph and do not cover other crystalline forms.
VI. Other Allegations
Indirect Infringement
- The complaint extensively pleads induced and contributory infringement for all asserted patents. The primary basis for these allegations is that Alkem's proposed product labels and marketing activities will allegedly encourage and instruct physicians and patients to use the generic products in a manner that infringes the asserted method claims (e.g., Compl. ¶¶118, 130, 166, 184, 202, 234). For the composition claims, contributory infringement is alleged on the basis that the products are especially made for an infringing use and are not suitable for substantial non-infringing use (Compl. ¶¶119, 143).
Willful Infringement
- While the complaint does not contain a separate count for willful infringement, it lays the groundwork by alleging that Alkem had knowledge of each patent-in-suit. This knowledge is predicated on the patents' listing in the FDA's Orange Book and on the Paragraph IV notice letters Alkem sent to Esperion (e.g., Compl. ¶¶117, 129, 141, 152, 173, 191, 207, 223, 239).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of technical and evidentiary proof: Can Plaintiff demonstrate through discovery and testing that Defendant's generic products actually contain the specific crystalline form of bempedoic acid and meet the precise purity (>98% or >99%) and impurity (<0.15%) profiles as recited in the various composition claims? The case for these patents will likely shift from the pleadings' reliance on bioequivalence representations to a fact-intensive dispute over the final product's chemical and physical characteristics.
- A second central question will be one of induced infringement: For the asserted method-of-use claims, does the specific language in Defendant’s proposed product labels actively instruct or encourage physicians and patients to perform the patented methods, thereby establishing the requisite intent for inducement under 35 U.S.C. § 271(b)?
- A key point of contention will be the viability of the indirect infringement theory against a single-API product: Can Plaintiff prove that Defendant’s marketing and labeling of its NEXLETOL® generic (containing only bempedoic acid) will specifically induce its combination use with a separate ezetimibe product to infringe the combination method claims of the ’816 Patent?