DCT
1:17-cv-01808
Amgen Inc v. Barr Laboratories Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Amgen Inc. (Delaware)
- Defendant: Barr Laboratories, Inc. (Delaware)
- Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP
- Case Identification: 1:17-cv-01808, D. Del., 12/15/2017
- Venue Allegations: Venue is asserted based on Defendant being a Delaware corporation with continuous and systematic contacts in the state, and having previously availed itself of the district's courts.
- Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) for generic cinacalcet hydrochloride tablets constitutes an act of infringement of a patent covering a rapid dissolution formulation for that compound.
- Technical Context: The technology concerns pharmaceutical formulations designed to improve the dissolution and bioavailability of cinacalcet, a poorly water-soluble drug used to treat hyperparathyroidism.
- Key Procedural History: This action arises under the Hatch-Waxman Act, triggered by Defendant's ANDA submission. The complaint notes that Defendant was previously found to infringe a different set of patents covering the same drug product, SENSIPAR®, in prior litigation. It also alleges that Defendant has been aware of the patent-in-suit but has not provided a Paragraph IV certification, which may be relevant to potential claims of willfulness.
Case Timeline
| Date | Event |
|---|---|
| 2003-09-12 | ’405 Patent Priority Date |
| 2004-03-08 | FDA approves Amgen's NDA for SENSIPAR® |
| 2008-06-13 | Barr sends letter notifying Amgen of its ANDA filing |
| 2010-05-13 | Barr receives tentative FDA approval for its ANDA |
| 2016-06-28 | U.S. Patent No. 9,375,405 issues |
| 2016-07-22 | ’405 Patent submitted for Orange Book listing |
| 2017-09-12 | Counsel for Teva (Barr's parent) and Amgen discuss the '405 patent |
| 2017-12-15 | Complaint filed |
| 2018-03-08 | Anticipated generic launch date by Defendant |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,375,405 - "Rapid Dissolution Formulation of a Calcium Receptor-Active Compound"
- Patent Identification: U.S. Patent No. 9,375,405, “Rapid Dissolution Formulation of a Calcium Receptor-Active Compound,” issued June 28, 2016.
The Invention Explained
- Problem Addressed: The patent's background section explains that calcium receptor-active compounds like cinacalcet HCl are often "insoluble or sparingly soluble in water," especially at neutral pH ('405 Patent, col. 1:10-13). This limited solubility can hinder the development of effective oral dosage forms and result in "low bioavailability" of the drug ('405 Patent, col. 1:19-24).
- The Patented Solution: The invention claims to solve this problem through a pharmaceutical composition with a "defined dissolution profile" ('405 Patent, col. 1:30-33). This is achieved by combining the active ingredient with a specific combination of pharmaceutically acceptable excipients (diluents, binders, and disintegrants) in particular weight-percentage ranges to ensure rapid release of the drug when ingested ('405 Patent, col. 1:39-51). The manufacturing process, detailed in a process flow diagram, is described as one way to achieve the desired granule and particle properties ('405 Patent, Fig. 1).
- Technical Importance: The claimed formulation provides a method for delivering a poorly soluble but therapeutically significant compound in a solid oral tablet that dissolves quickly, thereby addressing a key challenge in oral drug delivery for this class of molecules ('405 Patent, col. 1:21-24).
Key Claims at a Glance
- The complaint asserts infringement of at least independent claim 1 (Compl. ¶36).
- The essential elements of Claim 1 are:
- A pharmaceutical composition comprising:
- (a) from about 10% to about 40% by weight of cinacalcet HCl in an amount from about 20 mg to about 100 mg;
- (b) from about 45% to about 85% by weight of a diluent selected from a specified group (e.g., microcrystalline cellulose, starch);
- (c) from about 1% to about 5% by weight of a binder selected from a specified group (e.g., povidone); and
- (d) from about 1% to 10% by weight of a disintegrant selected from a specified group (e.g., crospovidone).
- Wherein the composition is for the treatment of hyperparathyroidism, hyperphosphonia, hypercalcemia, or elevated calcium phosphorus product. ('405 Patent, col. 12:17-44).
- A pharmaceutical composition comprising:
III. The Accused Instrumentality
Product Identification
- Defendant Barr's cinacalcet hydrochloride tablets in 30 mg, 60 mg, and 90 mg dosage strengths, as described in its Abbreviated New Drug Application (ANDA) No. 090476 (Compl. ¶4).
Functionality and Market Context
- The accused products are generic versions of Plaintiff's SENSIPAR® tablets, intended to be therapeutic equivalents for treating secondary hyperparathyroidism and other conditions related to elevated calcium levels (Compl. ¶14-16, ¶22). The filing of the ANDA itself is the act of infringement alleged under 35 U.S.C. § 271(e)(2), which allows for litigation before a generic drug is commercially launched (Compl. ¶35). The complaint alleges that Barr intends to launch its product as early as March 8, 2018 (Compl. ¶31).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint alleges that the product described in Barr's ANDA will infringe at least Claim 1 of the '405 patent, both literally and under the doctrine of equivalents (Compl. ¶36). As the ANDA's specific formulation is confidential, the allegations are made on information and belief, premised on the requirement that a generic product must be bioequivalent to the branded drug.
’405 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A pharmaceutical composition comprising: (a) from about 10% to about 40% by weight of cinacalcet HCl in an amount of from about 20 mg to about 100 mg; | Barr's ANDA products are identified as 30 mg, 60 mg, and 90 mg cinacalcet HCl tablets, which are amounts falling within the claimed range. It is alleged the weight percentage also meets this limitation. | ¶4, ¶36 | col. 12:18-20 |
| (b) from about 45% to about 85% by weight of a diluent selected from the group consisting of microcrystalline cellulose, starch...and mixtures thereof; | The complaint alleges infringement of the full claim, which requires the presence of a diluent from the specified list within the claimed weight percentage range. | ¶36 | col. 12:21-27 |
| (c) from about 1% to about 5% by weight of at least one binder selected from the group consisting of povidone...and mixtures thereof; | The complaint’s allegation of infringement requires that Barr's ANDA product contains a binder from the specified list within the claimed weight percentage range. | ¶36 | col. 12:28-33 |
| (d) from about 1% to 10% by weight of at least one disintegrant selected from the group consisting of crospovidone...and mixtures thereof; | The complaint’s allegation requires that Barr's ANDA product contains a disintegrant from the specified list within the claimed weight percentage range. | ¶36 | col. 12:34-39 |
| wherein the composition is for the treatment of at least one of hyperparathyroidism, hyperphosphonia, hypercalcemia, and elevated calcium phosphorus product. | The accused generic product is intended to treat the same medical conditions as SENSIPAR®, which include hyperparathyroidism, as would be indicated on its label. | ¶14-16, ¶36 | col. 12:39-44 |
- Identified Points of Contention:
- Factual Question: The central dispute will be whether the specific formulation in Barr's confidential ANDA actually contains the excipients (diluent, binder, disintegrant) in the weight percentages required by Claim 1. Resolution of this question depends on discovery of the ANDA's contents.
- Scope Questions: If Barr's formulation does not literally meet the claimed ranges, the doctrine of equivalents analysis will be critical (Compl. ¶36). This raises the question of whether any alternative excipients or percentages used by Barr perform substantially the same function in substantially the same way to achieve the same result as the claimed invention.
V. Key Claim Terms for Construction
The Term: "about" (e.g., "about 10% to about 40%")
Context and Importance: This term appears in every quantitative limitation of Claim 1. The infringement analysis will likely depend on whether the precise percentages in Barr's formulation fall within the claimed ranges. Practitioners may focus on this term because its construction will determine the literal boundaries of the claim; a broader interpretation could capture formulations that are numerically outside the stated ranges, while a narrower one could allow a defendant to design around the patent.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The repeated use of "about" throughout the claims and specification suggests the inventors did not intend for the percentage values to be absolute endpoints, but rather approximations sufficient to achieve the desired dissolution profile ('405 Patent, col. 8:14-24).
- Evidence for a Narrower Interpretation: The patent provides working examples with specific target percentages for each component ('405 Patent, col. 11, Table). A party could argue that "about" should be limited to a scope that reflects normal manufacturing tolerances or measurement precision around these exemplified values.
The Term: "diluent", "binder", "disintegrant"
Context and Importance: These terms define the required categories of excipients. A dispute may arise if Barr uses a single chemical compound that can perform more than one of these functions. The classification of the components in Barr's formulation will be critical to the infringement analysis for elements (b), (c), and (d) of Claim 1.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification lists compounds like starch and microcrystalline cellulose as diluents ('405 Patent, col. 12:23-24), which are known in the art to also possess properties of disintegrants or binders. This could support an interpretation where the functional categories are not strictly mutually exclusive.
- Evidence for a Narrower Interpretation: Claim 1 lists diluents, binders, and disintegrants in separate, distinct limitations (b), (c), and (d). This structure suggests that the claim requires three structurally or functionally distinct types of components, and that an excipient should be classified based on its primary function in the formulation as understood by a person of ordinary skill in the art.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that upon FDA approval, Barr's sale of its ANDA product will induce and/or contribute to the infringement of at least Claim 1 (Compl. ¶42). The basis for this allegation is that the product's label will instruct physicians and patients to administer the drug for the treatment of hyperparathyroidism and other patented indications, thereby inducing infringement of the claim's method-of-use limitation.
- Willful Infringement: While not using the word "willful," the complaint requests a declaration that this is an "exceptional case" and seeks attorneys' fees (Compl., Prayer for Relief ¶D). The factual basis for this is the allegation that Barr was aware of the '405 patent, citing its listing in the Orange Book and direct communication between counsel, but continued its plans to launch a generic product without changing course or filing a required Paragraph IV certification (Compl. ¶28-30, ¶41).
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary evidentiary question will be one of compositional identity: does the specific formulation detailed in Barr's confidential ANDA—including the identity and precise weight percentages of its chosen excipients—fall within the literal scope of the composition defined in Claim 1 of the '405 patent?
- A central legal issue will be one of definitional precision: how will the court construe the term "about" as used in the claim's quantitative limitations, and will that construction be broad enough to capture Barr’s formulation if it lies at or near the boundaries of the recited ranges?
- A key question for a potential finding of an exceptional case will be one of objective recklessness: do the complaint's allegations—that Barr knew of the '405 patent but failed to file a Paragraph IV certification and continued preparations for launch—support a finding that Barr proceeded despite a substantial and unjustifiable risk of infringement?