Boehringer Ingelheim Pharma Inc v. Ajanta Pharma Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Boehringer Ingelheim Pharmaceuticals Inc. (Delaware); Boehringer Ingelheim International GmbH (Germany); and Boehringer Ingelheim Corporation (Nevada)
  • Defendant: Ajanta Pharma Limited (India)
  • Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP; Kirkland & Ellis LLP
• Case Identification: 1:23-cv-00849, D. Del., 08/04/2023
• Venue Allegations: Venue is asserted on the basis that the defendant is a foreign corporation not residing in any U.S. judicial district and may therefore be sued in any district.
• Core Dispute: Plaintiff alleges that Defendant's submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Plaintiff's SYNJARDY® tablets constitutes an act of infringement of two patents covering pharmaceutical compositions and methods of use.
• Technical Context: The technology relates to methods of treating type 2 diabetes mellitus with the SGLT-2 inhibitor empagliflozin, particularly in patients who also have renal impairment or chronic kidney disease.
• Key Procedural History: The action arises under the Hatch-Waxman Act, triggered by Defendant’s submission of ANDA No. 217781 to the FDA. Plaintiff received notification letters from Defendant on or about September 12, 2022, containing a Paragraph IV certification that Defendant's proposed generic product would not infringe the patents-in-suit or that the patents are invalid.

Case Timeline

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

U.S. Patent No. 10,258,637 - "Pharmaceutical Composition, Method for Treating and Uses Thereof"

• Patent Identification: U.S. Patent No. 10258637, titled “Pharmaceutical Composition, Method for Treating and Uses Thereof,” issued on April 16, 2019 (the “’637 Patent”).

The Invention Explained

• Problem Addressed: The patent addresses the challenge of treating type 2 diabetes in patients who also suffer from renal impairment or chronic kidney disease (CKD). The background section notes that many conventional anti-diabetic agents, such as metformin, are restricted or require dose reduction in this patient population due to safety and efficacy concerns. (’637 Patent, col. 1:21-42).
• The Patented Solution: The invention provides a method for treating type 2 diabetes by administering the SGLT-2 inhibitor empagliflozin specifically to patients within defined ranges of renal function, as measured by their estimated glomerular filtration rate (eGFR). The method claims to offer a way to improve glycemic control in this specific, difficult-to-treat patient subset. (’637 Patent, Abstract; col. 2:50-61).
• Technical Importance: The claimed methods provide a therapeutic option for diabetic patients with moderate renal impairment, a population for whom other treatments may be contraindicated or less effective. (’637 Patent, col. 1:33-42).

Key Claims at a Glance

The complaint asserts infringement of "at least one claim" without further specification (Compl. ¶25). Independent claim 1 is representative of the patent's method claims.

• Independent Claim 1:
  • A method for improving glycemic control in a patient with type 2 diabetes mellitus.
  • The method comprises administering empagliflozin to the patient if their estimated glomerular filtration rate (eGFR) is ≥45 ml/min/1.73 m² and <60 ml/min/1.73 m².
  • The empagliflozin is administered orally in a total daily amount of 5 mg, 10 mg, 12.5 mg, or 25 mg.
  • The method results in improved glycemic control.
  • The method includes the step of discontinuing empagliflozin if the patient’s eGFR falls below 45 ml/min/1.73 m².

U.S. Patent No. 11,090,323 - "Pharmaceutical Composition, Methods for Treating and Uses Thereof"

• Patent Identification: U.S. Patent No. 11090323, titled “Pharmaceutical Composition, Methods for Treating and Uses Thereof,” issued on August 17, 2021 (the “’323 Patent”).

The Invention Explained

• Problem Addressed: As a continuation of the application leading to the ’637 Patent, the ’323 Patent addresses the same technical problem: the need for effective treatments for type 2 diabetes in patients with compromised renal function. (’323 Patent, col. 1:15-47).
• The Patented Solution: The invention provides methods of using empagliflozin to improve glycemic control in type 2 diabetes patients, with claims directed to a patient population with a different, and somewhat broader, range of moderate renal impairment compared to the ’637 Patent. (’323 Patent, Abstract; col. 2:50-57).
• Technical Importance: The invention extends the applicability of empagliflozin-based therapy to a wider range of patients with moderate chronic kidney disease, for whom therapeutic options can be limited. (’323 Patent, col. 1:33-42).

Key Claims at a Glance

The complaint asserts infringement of "at least one claim" (Compl. ¶39). Independent claim 1 is representative.

• Independent Claim 1:
  • A method for improving glycemic control in a patient with type 2 diabetes mellitus.
  • The method comprises administering empagliflozin to the patient if their eGFR is ≥30 ml/min/1.73 m² and <60 ml/min/1.73 m².
  • The empagliflozin is administered orally in a total daily amount of 10 mg or 25 mg.
  • The method results in improved glycemic control.

III. The Accused Instrumentality

• Product Identification: The accused products are Defendant Ajanta Pharma Limited’s proposed generic empagliflozin and metformin hydrochloride tablets, for which it submitted ANDA No. 217781 (the "Ajanta ANDA Products") (Compl. ¶8). The proposed dosages are 5 mg/500 mg, 5 mg/1 gm, 12.5 mg/500 mg, and 12.5 mg/1 gm (Compl. ¶8).
• Functionality and Market Context: The complaint alleges that the Ajanta ANDA Products are generic versions of Plaintiff's SYNJARDY® tablets and that Ajanta's ANDA filing relies on the SYNJARDY® New Drug Application (NDA) (Compl. ¶¶1, 23, 37). The filing includes data intended to demonstrate the bioequivalence of the Ajanta ANDA Products to SYNJARDY® (Compl. ¶¶23, 37). As such, the accused products are intended to be used for the same FDA-approved indications as SYNJARDY®, namely the treatment of type 2 diabetes. The act of infringement alleged is the statutory act of filing the ANDA to obtain approval for commercial manufacture and sale prior to the expiration of the patents-in-suit (Compl. ¶1).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not provide a detailed claim chart or a limitation-by-limitation analysis of infringement. It alleges that the submission of the ANDA is an act of infringement under 35 U.S.C. § 271(e)(2)(A) and that the future commercial sale and use of the Ajanta ANDA Products would directly and indirectly infringe the patents-in-suit (Compl. ¶¶25-28, 39-42). The central theory of infringement for the asserted method claims is that Ajanta is seeking approval for a drug with a proposed label that will instruct or encourage physicians and patients to administer the drug in a manner that practices the claimed methods. This includes administering empagliflozin to type 2 diabetes patients who fall within the specific eGFR ranges recited in the claims of the ’637 and ’323 Patents.

• Identified Points of Contention:
  • Infringement Scope: A primary dispute will likely concern whether the instructions and clinical information contained in the proposed label for the Ajanta ANDA Products will direct or encourage physicians to perform every step of the asserted method claims. This raises the question of whether the label language is merely informational or constitutes an affirmative instruction to infringe.
  • Claim Scope: Ajanta's Paragraph IV certification asserts non-infringement and/or invalidity (Compl. ¶¶24, 38). The non-infringement defense may hinge on arguments that the proposed label does not meet specific limitations, such as the mandatory "discontinuing" step in claim 1 of the ’637 Patent. The invalidity defense may question whether the patent specification adequately describes and enables a method of treatment defined by precise numerical eGFR boundaries.

V. Key Claim Terms for Construction

• The Term: "improving glycemic control" (’637 Patent, Claim 1; ’323 Patent, Claim 1)
  • Context and Importance: This term defines the purpose and outcome of the claimed method. Its construction is central to determining whether the intended use of the accused product achieves the claimed result and thus falls within the scope of the claims.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification suggests that improving glycemic control can encompass reducing "fasting plasma glucose, of postprandial plasma glucose and/or of glycosylated hemoglobin HbA1c" (’637 Patent, col. 2:1-4). This language could support a construction where a reduction in any of these metrics constitutes "improving."
    • Evidence for a Narrower Interpretation: The patent includes extensive clinical data showing specific, statistically significant reductions in HbA1c and fasting plasma glucose in patients treated with empagliflozin (’637 Patent, FIG. 1A, FIG. 7A). A party might argue these examples implicitly define "improving" as achieving a reduction of a certain clinical or statistical magnitude.
• The Term: "discontinuing empagliflozin if the eGFR of the patient falls below 45 ml/min/1.73 m²" (’637 Patent, Claim 1)
  • Context and Importance: This active step of ceasing treatment is a required limitation of claim 1 of the ’637 Patent. For infringement to be induced, Defendant's proposed label would need to instruct this specific action.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent claims this as an integral part of the "method," using mandatory-sounding language: "the method further comprises discontinuing empagliflozin" (’637 Patent, col. 4:8-9). This suggests that any label instruction that leads a physician to stop treatment under these conditions would satisfy the element.
    • Evidence for a Narrower Interpretation: A defendant could argue that standard pharmaceutical labels provide recommendations and warnings, leaving final treatment decisions to a physician's discretion. The question for claim construction may be whether a recommendation to stop treatment is equivalent to the affirmative step of "discontinuing" as part of a patented method.

VI. Other Allegations

• Indirect Infringement: The complaint alleges that Defendant's offering to sell the Ajanta ANDA Products would actively induce infringement (Compl. ¶¶32, 46). The factual basis for this allegation is Defendant’s knowledge of the patents and the allegation that its "promotional activities and package inserts for its ANDA Products" will instruct users in a manner that directly infringes the method claims (Compl. ¶¶31, 45).
• Willful Infringement: The complaint does not explicitly allege "willful" infringement. However, it does plead that this is an "exceptional case" under 35 U.S.C. § 285, which would warrant an award of attorneys' fees (Compl. ¶¶34, 49). The basis for this appears to be Defendant's knowledge of the patents, evidenced by its submission of the Paragraph IV certification letters (Compl. ¶¶24, 38).

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

• A core issue will be one of induced infringement: does the specific language in Defendant’s proposed product label constitute an affirmative instruction that would lead physicians and patients to perform all steps of the asserted method claims, or does it merely provide clinical information that leaves the infringing acts to the physician's independent medical judgment?
• A key invalidity question will likely be one of written description and enablement: does the patent specification provide adequate support for claims covering a method of treatment defined by the precise numerical eGFR ranges, or are these ranges subject to challenge as being arbitrary or not fully described and enabled across their entire scope?
• A central question of claim scope will be whether the negative limitation in the ’637 Patent requiring the "discontinuing" of treatment if a patient's eGFR falls below a certain threshold is a step that Defendant's proposed label will instruct, and whether a label's recommendation or warning can satisfy such a mandatory method step.