DCT
2:17-cv-13312
Eli Lilly Co v. Unichem Laboratories Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Eli Lilly and Company (Indiana) and ICOS Corporation (Delaware)
- Defendant: Unichem Laboratories Limited (India) and Unichem Pharmaceuticals (USA) Inc. (New Jersey)
- Plaintiff’s Counsel: McCarter & English, LLP
- Case Identification: 2:17-cv-13312, D.N.J., 12/19/2017
- Venue Allegations: Venue is alleged based on Defendant Unichem USA’s incorporation and principal place of business in New Jersey, and on Defendant Unichem Ltd.’s filing of an Abbreviated New Drug Application (ANDA) seeking to market its product throughout the U.S., including in New Jersey.
- Core Dispute: Plaintiffs allege that Defendants’ 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 of using tadalafil to treat sexual dysfunction.
- Technical Context: The technology relates to low-dose oral formulations of tadalafil, a selective PDE5 inhibitor, for the treatment of sexual dysfunction, a significant pharmaceutical market.
- Key Procedural History: This action was initiated under the Hatch-Waxman Act, triggered by Defendants’ filing of ANDA No. 209250 with a “Paragraph IV certification.” This certification asserts that Plaintiffs’ patent is invalid, unenforceable, or will not be infringed by the proposed generic product.
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 Issued |
| 2017-11-15 | Date of Defendant's "Notice Letter" regarding ANDA filing |
| 2017-12-19 | 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, Issued September 13, 2005
The Invention Explained
- Problem Addressed: The patent describes a need for improved pharmaceutical products for treating sexual dysfunction. It notes that existing treatments, such as sildenafil (Viagra®), can cause undesirable side effects like facial flushing and vision abnormalities, and can have dangerous hypotensive effects when used with organic nitrates ('166 Patent, col. 1:57-col. 2:12).
- The Patented Solution: The invention is a method of treatment using a specific compound, tadalafil, which is a highly selective inhibitor of the PDE5 enzyme ('166 Patent, col. 2:22-31). By administering this compound in a specific low oral dosage range—about 1 to 20 mg—the method claims to effectively treat sexual dysfunction while minimizing the side effects associated with less selective or higher-dosed inhibitors ('166 Patent, col. 2:31-48).
- Technical Importance: The claimed method provided a therapeutic option for individuals who may have been unable to use prior treatments, including those with cardiovascular conditions requiring nitrate therapy or those susceptible to other side effects ('166 Patent, col. 2:40-48).
Key Claims at a Glance
- The complaint asserts infringement of independent claim 1 and dependent claims 2, 4, 5, and 7-12 ('166 Patent, col. 14:66-col. 16:17; Compl. ¶35).
- Independent Claim 1:
- 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 [tadalafil].
III. The Accused Instrumentality
Product Identification
- The accused instrumentality is Defendant Unichem’s "proposed tadalafil ANDA product," submitted to the FDA for approval under ANDA No. 209250 (Compl. ¶1).
Functionality and Market Context
- The complaint alleges the accused product is a generic version of Plaintiffs’ Cialis® product, formulated as tablets containing tadalafil as the active ingredient (Compl. ¶1, ¶37). The ANDA seeks approval for dosage strengths of 2.5 mg, 5 mg, 10 mg, and 20 mg (Compl. ¶31, ¶37). The infringement alleged is statutory infringement under 35 U.S.C. § 271(e)(2), which makes the submission of an ANDA for a patented drug an act of infringement to enable litigation before the generic product enters the market (Compl. ¶55). The complaint alleges that upon approval, the product will be marketed for the treatment of male erectile dysfunction, consistent with the FDA-approved label for Cialis® (Compl. ¶38-39).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
'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 ANDA product to treat "male erectile dysfunction," which the complaint alleges is a form of "sexual dysfunction," consistent with the FDA-approved label for Cialis®. | ¶38, ¶39, ¶42 | col. 14:66-67; col. 15:16-17 |
| comprising orally administering one or more unit dose | The accused product is a tablet intended for oral administration. | ¶37, ¶45 | col. 15:1-2 |
| containing about 1 to about 20 mg, up to a maximum total dose of 20 mg per day, | Defendant seeks approval for its product in 2.5 mg, 5 mg, 10 mg, and 20 mg dosage strengths, all of which fall within the claimed range of "about 1 to about 20 mg." | ¶37, ¶43 | col. 15:2-5 |
| of a compound having the structure [(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] | Defendant admits in its Notice Letter that the proposed product will be a tablet and will contain tadalafil, which is the compound with the claimed structure, as its active ingredient. | ¶37 | col. 15:5-15 |
- Identified Points of Contention:
- Scope Questions: The case may raise questions about the relationship between the claimed method of treating "sexual dysfunction" (Claim 1) and the accused product's expected indication for "male erectile dysfunction." While the latter is a species of the former, and is explicitly recited in dependent claim 2 (Compl. ¶40), a defendant in an ANDA case could attempt to argue its proposed label does not meet every limitation of the broader claim.
- Technical Questions: As an ANDA case based on a method-of-use patent, the central question is not about the composition of the accused product itself, but whether the act of seeking FDA approval for that product with its proposed label constitutes infringement. The dispute will likely focus on whether the instructions and indications on the defendant's proposed label will inevitably lead to direct infringement by patients and physicians. The complaint repeatedly notes that Defendant's Notice Letter allegedly fails to provide a "factual and legal basis" for its non-infringement assertion (Compl. ¶38, ¶41, ¶48).
V. Key Claim Terms for Construction
- The Term: "sexual dysfunction"
- Context and Importance: This term defines the scope of the patented method. Its construction is critical because infringement will turn on whether the indication for which the defendant seeks FDA approval falls within its meaning. Practitioners may focus on this term to determine if the defendant could use a "skinny label" to "carve out" the patented indication, although this may be difficult where the primary, commercially viable use is the one patented.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The plain language of Claim 1 uses the general term "sexual dysfunction" without limitation. The specification provides further support by identifying multiple types of sexual dysfunction, stating that "Specific conditions that can be treated by the present invention, include, but are not limited to, male erectile dysfunction and female sexual dysfunction" ('166 Patent, col. 3:7-10).
- Evidence for a Narrower Interpretation: A defendant might point to dependent claim 2, which recites "[t]he method of claim 1 wherein the sexual dysfunction is male erectile dysfunction" ('166 Patent, col. 15:16-17), to argue under the doctrine of claim differentiation that the scope of "sexual dysfunction" in Claim 1 must be broader than, and not limited to, male erectile dysfunction. However, this argument typically serves to confirm that the broader term encompasses the narrower one.
VI. Other Allegations
- Indirect Infringement: The complaint is premised on induced infringement. It alleges that Defendant's future marketing and sale of its product, with a label instructing use for treating male erectile dysfunction, will induce infringement of the '166 patent by physicians and patients (Compl. ¶35). The basis for this allegation is the ANDA filing itself, which seeks approval for a product whose intended use, as dictated by its proposed label, will allegedly be the patented method (Compl. ¶38-39).
- Willful Infringement: The complaint does not contain a formal count for willful infringement. However, it establishes a basis for pre-suit knowledge by referencing the "Notice Letter" sent by Defendant to Plaintiffs, which notified Plaintiffs of the ANDA filing and the Paragraph IV certification against the '166 patent (Compl. ¶31).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of induced infringement: Will the final, FDA-approved label for Unichem’s proposed generic tadalafil product contain an indication for "male erectile dysfunction" that inevitably instructs users to practice the patented method of treating "sexual dysfunction"? The case will likely hinge on the contents of that proposed label and whether any attempt to "carve out" the patented use is legally and commercially feasible.
- A secondary issue is one of claim construction: Can the term "sexual dysfunction" in Claim 1 be interpreted in a way that would not cover the specific indication of "male erectile dysfunction" for which the accused product will likely be marketed? Given the patent’s specification and dependent claims, this presents a significant challenge for the defendant.