DCT
3:11-cv-00481
Ferring BV v. Watson Laboratories
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Ferring B.V. (Netherlands)
- Defendant: Watson Pharmaceuticals, Inc. (Nevada), Watson Laboratories, Inc. (Nevada), Watson Laboratories, Inc. - Florida (Florida), Watson Pharma, Inc. (Delaware)
- Plaintiff’s Counsel: Jones Vargas; Finnegan Henderson Farabow Garrett & Dunner, LLP
- Case Identification: 3:11-cv-00481, D. Nev., 07/07/2011
- Venue Allegations: Venue is alleged based on Defendants' business operations, including the marketing and sale of generic drug products, within the District of Nevada, making the district a likely destination for the accused products.
- Core Dispute: Plaintiff alleges that Defendants' submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Plaintiff's Lysteda® product constitutes an act of infringement of a patent covering modified release formulations of tranexamic acid.
- Technical Context: The technology relates to oral pharmaceutical formulations designed to treat heavy menstrual bleeding (menorrhagia) by modifying the release profile of the active ingredient to improve patient tolerability.
- Key Procedural History: This action was triggered by Defendants' filing of ANDA No. 202093 and their subsequent "Notice of Certification" letter to Plaintiff, dated May 24, 2011, asserting that the patent-in-suit is invalid, unenforceable, or will not be infringed by the proposed generic product. The patent-in-suit is listed in the FDA's "Orange Book" as covering Plaintiff's approved Lysteda® drug product.
Case Timeline
| Date | Event |
|---|---|
| 2004-03-04 | ’739 Patent Priority Date |
| 2009-11-13 | FDA approves Plaintiff's New Drug Application (NDA) for Lysteda® |
| 2011-05-24 | ’739 Patent Issue Date |
| 2011-05-24 | Date of Defendant's Notice of Certification letter to Plaintiff |
| 2011-07-07 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,947,739 - “Tranexamic Acid Formulations”
- Issued: May 24, 2011
The Invention Explained
- Problem Addressed: The patent’s background section states that conventional, immediate-release oral formulations of tranexamic acid can cause significant gastrointestinal side effects, such as nausea, vomiting, and diarrhea, due to the rapid release of a large quantity of the drug into the stomach. (’739 Patent, col. 1:39-50).
- The Patented Solution: The invention is a modified release oral tablet that slows the release of tranexamic acid after ingestion. This prevents a concentrated "bolus" of the drug from entering the stomach at once, which is intended to reduce the adverse gastrointestinal effects and thereby improve patient compliance with the therapy. (’739 Patent, Abstract; col. 5:6-24).
- Technical Importance: By improving the tolerability of tranexamic acid, the invention provides a more viable non-hormonal, non-invasive medical therapy for menorrhagia, a common and persistent condition. (’739 Patent, col. 5:60-65).
Key Claims at a Glance
- The complaint asserts infringement of at least one claim of the ’739 patent. The independent claims are Claim 1 and Claim 11.
- Independent Claim 1 recites:
- A tranexamic acid tablet formulation comprising tranexamic acid and a modified release material.
- The modified release material is a specified type of polymer (e.g., hydroxyalkylcellulose) present in an amount from about 10% to 35% by weight of the formulation.
- The formulation has an in-vitro dissolution profile where less than about 70% of the drug is released at 45 minutes, and about 100% is released by 120 minutes.
- Each tablet provides a dose of about 650 mg of tranexamic acid.
- Independent Claim 11 recites:
- A tranexamic acid tablet formulation comprising tranexamic acid and a modified release material, with the polymer type and weight percentage limitations similar to Claim 1.
- The formulation has an in-vitro dissolution profile where it releases from about 10% to about 25% of the drug every 15 minutes, with about 100% released by 120 minutes.
- Each tablet provides a dose of about 650 mg of tranexamic acid.
- The complaint does not explicitly reserve the right to assert dependent claims, though such a right is standard practice.
III. The Accused Instrumentality
Product Identification
- The accused instrumentality is Defendants' generic tranexamic acid tablets, for which FDA approval is sought under ANDA No. 202093 (Compl. ¶16).
Functionality and Market Context
- The accused product is a tablet formulation containing 650 mg of tranexamic acid (Compl. ¶19).
- It is intended to be a generic version of Plaintiff's branded Lysteda® product and is alleged to be "the same, or substantially the same" (Compl. ¶21). In the context of a Hatch-Waxman ANDA filing, this allegation implies that the accused product is bioequivalent to the branded product and is intended for the same therapeutic use. The complaint does not contain specific details about the excipients or release profile of the accused product, as that information is contained within the confidential ANDA submission.
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint provides a "notice pleading" of infringement under 35 U.S.C. § 271(e)(2)(A), which defines the submission of an ANDA as an act of infringement if the proposed generic product would infringe the patent upon commercialization. The infringement theory is based on the allegation that the ANDA product is a generic equivalent of the patent-protected Lysteda® product.
’739 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A tranexamic acid tablet formulation, comprising: tranexamic acid or a pharmaceutically acceptable salt thereof | Defendants' ANDA product is a tablet formulation containing 650 mg of tranexamic acid. | ¶19 | col. 6:46-49 |
| a modified release material, wherein the modified release material comprises a polymer selected from the group consisting of hydroxyalkylcelluloses, alkylcelluloses, cellulose ethers, partial esters thereof, and mixtures thereof | The complaint does not specify the excipients in the ANDA product but alleges the product is the "same, or substantially the same" as Lysteda®, which is covered by the patent. | ¶21 | col. 6:49-54 |
| wherein the modified release material is present in the formulation in an amount from about 10% to about 35% by weight of the formulation | The complaint does not provide details on the weight percentage of excipients in the ANDA product. Infringement is inferred from the allegation that the generic is substantially the same as the patented product. | ¶21 | col. 6:55-57 |
| wherein the formulation provides an in-vitro dissolution release rate ... of less than about 70% ... released at about 45 minutes, and about 100% ... released by about 120 minutes | The complaint does not provide the dissolution profile of the ANDA product. Infringement is based on the allegation that the product is a generic equivalent intended to be bioequivalent to the patented product. | ¶21 | col. 6:58-64 |
| wherein each tablet of the formulation provides a dose of about 650 mg of tranexamic acid | The ANDA product is a tablet containing 650 mg of tranexamic acid. | ¶19 | col. 6:65-67 |
Identified Points of Contention
- Scope Questions: A central dispute will concern whether the specific excipients used in Defendants' ANDA formulation fall within the definition of "modified release material" as claimed in the patent. The construction of this term, particularly the scope of the listed polymer groups, will be critical.
- Technical Questions: A key factual question will be whether the in-vitro dissolution profile of Defendants' proposed generic tablet meets the specific numerical release rate limitations recited in the independent claims (e.g., Claim 1's "<70% at 45 minutes" or Claim 11's "10%-25%...every 15 minutes"). This will likely depend on expert analysis of data contained in the confidential ANDA filing.
V. Key Claim Terms for Construction
The Term: "modified release material"
- Context and Importance: This term is the technological core of the invention, distinguishing it from prior art immediate-release formulations. Whether Defendants' formulation contains such a material as claimed will be a dispositive issue for infringement. Practitioners may focus on this term because its scope determines whether Defendants' specific blend of excipients is covered by the patent.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent states that the invention is directed to formulations that "minimize or eliminate" gastrointestinal side effects by preventing a "bolus of tranexamic acid" from entering the stomach, suggesting a functional definition. (’739 Patent, col. 5:6-12). The specification also provides a long list of suitable polymers, including hydroxypropylmethylcellulose, methyl cellulose, and others, which could support a broad construction encompassing various release-controlling agents. (’739 Patent, col. 21:11-20).
- Evidence for a Narrower Interpretation: The patent’s examples focus on specific formulations using Hypromellose (a type of hydroxypropylmethylcellulose) as the release-controlling agent. (’739 Patent, col. 28, Table 1). A party could argue that the term should be construed more narrowly in light of these specific working examples.
The Term: "about" (as in "about 650 mg" and "about 10% to about 35%")
- Context and Importance: This term appears in relation to the dosage and the weight percentage of the release material. The ANDA product is for a 650 mg tablet, but the precise scope of "about" could be determinative if Defendants' formulation deviates even slightly from the recited values.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The repeated use of "about" throughout the claims and specification suggests the patentee did not intend to be limited to the exact numerical values, but rather to encompass minor variations that are common in pharmaceutical manufacturing and still achieve the same function.
- Evidence for a Narrower Interpretation: A party could argue that in the context of pharmaceutical formulation, where precision is high, "about" should be interpreted very narrowly. The focus on the specific 650 mg dosage, corresponding to the branded Lysteda® product, may suggest the patentee intended to claim a very specific formulation.
VI. Other Allegations
Indirect Infringement
- The complaint alleges that Defendants will contributorily infringe and induce infringement through the future manufacture and sale of the generic tablets (Compl. ¶23). The implied basis for an inducement claim in a Hatch-Waxman case is the proposed drug label that would be filed with the ANDA, which would instruct physicians and patients to use the generic drug for the patented method of treatment.
Willful Infringement
- The complaint does not explicitly allege willful infringement. However, it requests that the court declare the case "exceptional" under 35 U.S.C. § 285 and award attorneys' fees (Prayer for Relief ¶5). The factual basis for this request is not detailed but could later be tied to Defendants' knowledge of the patent through its listing in the FDA Orange Book and the statutory notice letter process (Compl. ¶¶14, 18).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of formulation equivalence: Do the specific excipients and their respective quantities in Defendants' ANDA product fall within the scope of the "modified release material" and its claimed weight percentages as defined by the ’739 patent?
- A key evidentiary question will be one of functional performance: Does the in-vitro dissolution profile of Defendants' proposed generic tablet meet the specific, numerical release-rate limitations required by the asserted claims, or is there a technical mismatch that avoids infringement?