DCT

2:17-cv-01951

Eli Lilly Co v. Hetero USA Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:17-cv-01951, D.N.J., 03/24/2017
  • Venue Allegations: Venue is asserted based on Defendant Hetero USA Inc.'s principal place of business in New Jersey, its substantial and continuous business contacts within the district, and the allegation that the district is a destination for its generic products. The complaint also asserts specific jurisdiction based on the filing of an Abbreviated New Drug Application (ANDA) that predicts future marketing activities purposefully directed at the district.
  • Core Dispute: Plaintiffs allege that Defendant’s submission of an ANDA to the FDA seeking approval to market a generic version of Cialis® (tadalafil) constitutes an act of infringement of a patent covering a method for treating sexual dysfunction.
  • Technical Context: The technology relates to pharmaceutical methods of use for a selective phosphodiesterase type 5 (PDE5) inhibitor, a class of drugs used to treat erectile dysfunction, which represents a significant commercial market.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendant’s notification to Plaintiffs of its ANDA filing containing a Paragraph IV certification. The complaint notes this matter is related to a series of previously filed and consolidated infringement actions in the Eastern District of Virginia against other generic drug manufacturers concerning the same active ingredient.

Case Timeline

Date Event
1999-04-30 U.S. Patent No. 6,943,166 Priority Date
2005-09-13 U.S. Patent No. 6,943,166 Issue Date
2017-02-08 Defendant sends Notice Letter regarding tadalafil ANDA
2017-03-24 Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,943,166 - "Compositions Comprising Phosphodiesterase Inhibitors for the Treatment of Sexual Dysfunction"

  • Patent Identification: U.S. Patent No. 6,943,166, “Compositions Comprising Phosphodiesterase Inhibitors for the Treatment of Sexual Dysfunction,” issued September 13, 2005. (’166 Patent, cover; Compl. ¶36).

The Invention Explained

  • Problem Addressed: The patent’s background section describes the limitations of the then-available PDE5 inhibitor, sildenafil. These limitations included significant adverse side effects such as facial flushing and vision abnormalities, as well as a clinically significant drop in blood pressure when used with organic nitrates, which created a contraindication for certain patients. (’166 Patent, col. 1:56–col. 2:11).
  • The Patented Solution: The patent discloses a method of treating sexual dysfunction by orally administering a specific compound, (6R,12aR)-2,3,6,7,12,12a-hexahydro-2-methyl-6-(3,4-methylenedioxyphenyl)-pyrazino[2',1':6,1]pyrido[3,4-b]indole-1,4-dione (tadalafil), in a low-dose range of about 1 to 20 mg per day. (’166 Patent, Abstract; col. 2:57-65). This specific dosage regimen is described as providing effective therapy while minimizing the side effects associated with prior art PDE5 inhibitors, thereby making the treatment available to individuals who were previously untreatable, such as those with certain cardiovascular conditions. (’166 Patent, col. 2:40-54).
  • Technical Importance: The claimed invention provided a method of treatment for sexual dysfunction with a potentially improved safety and side-effect profile compared to the first-generation drug in its class, which could expand the addressable patient population. (’166 Patent, col. 2:40-54).

Key Claims at a Glance

  • The complaint asserts independent claim 1 and dependent claims 2, 4, 5, and 7-12. (Compl. ¶43).
  • Independent Claim 1 of the ’166 Patent recites the following essential elements:
    • A method of treating sexual dysfunction in a patient in need thereof
    • comprising orally administering one or more unit dose
    • containing about 1 to about 20 mg, up to a maximum total dose of 20 mg per day,
    • of a compound having the structure [of tadalafil].

III. The Accused Instrumentality

Product Identification

  • Defendant’s proposed generic tadalafil tablets, which are the subject of Abbreviated New Drug Application No. 209908. (Compl. ¶1).

Functionality and Market Context

  • The accused instrumentality is the filing of the ANDA seeking FDA approval to market tadalafil tablets in 2.5 mg, 5 mg, 10 mg, and 20 mg dosage strengths. (Compl. ¶39). The complaint alleges that Defendant’s proposed product contains tadalafil as its active ingredient and will, upon information and belief, be marketed for the treatment of sexual dysfunction, consistent with the FDA-approved label for the branded drug Cialis®. (Compl. ¶45, ¶47). This positions the proposed product as a direct generic substitute for Plaintiffs' Cialis® product. No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

'166 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a method of treating sexual dysfunction in a patient in need thereof Defendant will market its proposed tadalafil product to treat sexual dysfunction, consistent with the FDA-approved label for Cialis®, which is indicated for male erectile dysfunction. The proposed label will instruct and encourage this use. ¶46, ¶47 col. 14:65-67
comprising orally administering one or more unit dose Defendant’s proposed product is a tablet, which is a unit dose form intended for oral administration. ¶45 col. 14:67–col. 15:1
containing about 1 to about 20 mg, up to a maximum total dose of 20 mg per day, Defendant’s ANDA seeks approval for 2.5 mg, 5 mg, 10 mg, and 20 mg dosage strengths, which fall within the claimed dosage range and daily maximum. ¶39, ¶45 col. 15:1-3
of a compound having the structure [shown, which is tadalafil]. Defendant’s Notice Letter admits that its proposed product contains tadalafil as the active ingredient. ¶45 col. 15:3-15
  • Identified Points of Contention:
    • Scope Questions: In this ANDA litigation context, a primary infringement question is whether the proposed label for Defendant's generic product will inevitably instruct medical professionals and patients to perform the patented method. The complaint alleges that Defendant’s Notice Letter provides no factual or legal basis for non-infringement, suggesting Plaintiffs' view that the proposed use directly maps onto the claim elements. (Compl. ¶46). The dispute may turn on any differences between the proposed label and the patent claims.
    • Technical Questions: The core of the case, as is common in Hatch-Waxman litigation, is more likely to concern the validity and/or enforceability of the ’166 Patent, which Defendant challenged in its Paragraph IV certification. (Compl. ¶42). The technical questions will likely relate to defenses such as obviousness based on prior art knowledge of other PDE5 inhibitors, or invalidity for lack of written description or enablement for the full scope of the claims.

V. Key Claim Terms for Construction

  • The Term: "about 1 to about 20 mg"
    • Context and Importance: This term defines the claimed dosage range. Practitioners may focus on this term to challenge the patent's validity, potentially arguing that the word "about" renders the claim indefinite or that the full range is not supported by the specification. Defendant’s proposed dosage strengths of 2.5, 5, 10, and 20 mg fall within the literal range, making the construction of "about" critical to the scope and validity of the claim. (Compl. ¶45).
    • Evidence for a Broader Interpretation: The use of "about" suggests the inventors did not intend to be limited to the exact numerical values. The specification's clinical data tables show that doses up to 100 mg were studied, but adverse events increased significantly above the 20 mg dose, which may support the upper limit as a critical, but not necessarily rigid, boundary. (’166 Patent, col. 14:20-35).
    • Evidence for a Narrower Interpretation: The specification describes a dose of "about 5 to about 20 mg/day" as preferable and a "10 mg dosage form" as most preferable. (’166 Patent, col. 3:19-21). A party could argue that these preferred embodiments should guide the interpretation of "about," limiting it to a narrow range around the disclosed values.
  • The Term: "sexual dysfunction"
    • Context and Importance: This term defines the medical condition to be treated and is central to the method claim's scope. Its construction will be critical for assessing the patent's validity, particularly for written description and enablement. A defendant may argue that the specification only enables treatment for a narrower condition, such as male erectile dysfunction, while the claim covers a broader scope.
    • Evidence for a Broader Interpretation: The patent explicitly states that treatable conditions include "male erectile dysfunction and female sexual dysfunction, particularly female arousal disorder." (’166 Patent, col. 3:7-11). This language directly supports a construction that is not limited to male-specific conditions.
    • Evidence for a Narrower Interpretation: The detailed clinical data provided in the examples section of the patent focuses exclusively on studies in men with erectile dysfunction. (’166 Patent, Examples 5, 6, 7). A party could argue that this lack of data for other forms of sexual dysfunction fails to provide adequate written description to support the full, broad scope of the term as claimed.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendant will induce infringement of the asserted claims. (Compl. ¶43). This allegation is based on the theory that Defendant’s proposed product label will instruct and encourage physicians to prescribe and patients to use the generic tadalafil tablets in a manner that directly practices the steps of the patented method of treatment. (Compl. ¶47, ¶50).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central issue will be one of patent validity: Can the defendant demonstrate by clear and convincing evidence that the asserted method-of-use claims are invalid, for instance, as obvious in light of prior art PDE5 inhibitors or for lacking adequate written description and enablement to support the full scope of the claimed dosage range and the broad term "sexual dysfunction"?
  • Another key question will be one of induced infringement: Assuming the patent is valid, will the final FDA-approved label for Defendant's generic product contain indications and instructions that will necessarily lead physicians and patients to practice the patented method? The outcome may depend on the precise language of the approved label and whether Defendant pursues a "skinny label" strategy to carve out any patented uses.