1:23-cv-01382
AstraZeneca Ab v. Sun Pharmaceutical Industries Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: AstraZeneca AB (Sweden)
- Defendant: Sun Pharmaceutical Industries Limited (India) and Sun Pharmaceutical Industries, Inc. (Delaware)
- Plaintiff’s Counsel: McCarter & English, LLP
- Case Identification: 1:23-cv-01382, D. Del., 12/04/2023
- Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendant Sun Inc. is incorporated in Delaware, and Defendant Sun Ltd. is a foreign corporation that may be sued in any judicial district.
- Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff's QTERN® drug product constitutes an act of patent infringement.
- Technical Context: The technology at issue is a specific C-aryl glucoside compound, known as dapagliflozin, which functions as an SGLT2 inhibitor for the treatment of type 2 diabetes.
- Key Procedural History: The litigation was initiated under the Hatch-Waxman Act, triggered by Defendants' submission of ANDA No. 211492 with a Paragraph IV certification, asserting that the patent-in-suit is invalid, unenforceable, or will not be infringed. The complaint was filed within the 45-day statutory window following Plaintiff's receipt of Defendants' notice letter. The patent-in-suit has received a patent term extension, and its expiration date is listed as October 4, 2025.
Case Timeline
| Date | Event |
|---|---|
| 1999-10-12 | ’117 Patent Priority Date |
| 2003-02-04 | ’117 Patent Issue Date |
| 2017-02-28 | FDA approves AstraZeneca's NDA No. 209091 for QTERN® |
| 2020-03-11 | Sun Inc. incorporates in Delaware |
| 2023-10-20 | Sun provides Paragraph IV Notice Letter to AstraZeneca |
| 2023-12-04 | Complaint Filing Date |
| 2025-10-04 | ’117 Patent Expiration Date (with patent term extension) |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,515,117 - "C-Aryl Glucoside SGLT2 Inhibitors and Method" (issued Feb. 4, 2003)
The Invention Explained
- Problem Addressed: The patent addresses the problem of hyperglycemia (high blood sugar) in patients with type II diabetes, which results from excessive glucose production by the liver and peripheral insulin resistance (U.S. Patent No. 6,515,117, col. 1:21-29). The background notes a need for novel, safe, and orally active antidiabetic agents to normalize plasma glucose and complement existing therapies (U.S. Patent No. 6,515,117, col. 1:39-47).
- The Patented Solution: The invention is a specific C-aryl glucoside compound that selectively inhibits the sodium-dependent glucose transporter 2 (SGLT2) located in the kidney's proximal tubules (U.S. Patent No. 6,515,117, col. 2:20-25; col. 2:56-64). By inhibiting SGLT2, the patented compound blocks the reabsorption of glucose from the filtrate back into the blood, causing excess glucose to be excreted in the urine. This mechanism is intended to lower plasma glucose levels in diabetic patients (U.S. Patent No. 6,515,117, col. 1:30-38).
- Technical Importance: This selective inhibition of SGLT2 represented a targeted therapeutic approach. It was designed to avoid the adverse effects of non-specific inhibitors (like phlorizin), which also inhibit SGLT1, a transporter found in the small intestine, and can lead to undesirable gastrointestinal side effects (U.S. Patent No. 6,515,117, col. 2:59-col. 3:8).
Key Claims at a Glance
- The complaint asserts infringement of at least independent claim 1 and method of use claim 14 (Compl. ¶¶46-49).
- Independent Claim 1: Claims a single compound having a specific chemical structure (dapagliflozin), as well as its pharmaceutically acceptable salts, stereoisomers, and prodrug esters.
- The complaint reserves the right to assert infringement of other claims (Compl., Prayer for Relief ¶2).
III. The Accused Instrumentality
Product Identification
Defendants’ proposed "10 mg/5 mg dapagliflozin/saxagliptin hydrochloride tablets," which are the subject of ANDA No. 211492 (Compl. ¶1).
Functionality and Market Context
The accused product is a generic version of AstraZeneca’s brand-name drug, QTERN®, which is approved as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes (Compl. ¶¶1, 42). The infringement alleged is the statutory act of filing the ANDA under 35 U.S.C. § 271(e)(2)(A) to obtain FDA approval to market this generic drug prior to the expiration of the ’117 patent (Compl. ¶46).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint alleges that the submission of ANDA No. 211492 is a per se act of infringement under 35 U.S.C. § 271(e)(2)(A) and that the future commercialization of the product described in the ANDA would constitute infringement under 35 U.S.C. § 271(a), (b), and/or (c) (Compl. ¶¶46-47).
'117 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A compound having the structure [image of dapagliflozin] | Defendants’ ANDA No. 211492 seeks approval to market "dapagliflozin/saxagliptin hydrochloride tablets" (Compl. ¶1). The complaint alleges that the submission of this ANDA for a product containing the claimed compound infringes at least claim 1 of the ’117 patent (Compl. ¶46). | ¶1, ¶46 | col. 25:1-15 |
| or a pharmaceutically acceptable salt, a stereoisomer thereof, or a prodrug ester thereof. | The complaint alleges that the products described in ANDA No. 211492 would infringe, which may implicate a salt or stereoisomer form of the claimed compound (Compl. ¶46). | ¶46 | col. 25:15-18 |
Identified Points of Contention
- Technical Questions: The central technical question is whether the dapagliflozin active pharmaceutical ingredient described in Defendants' ANDA No. 211492 is structurally identical to the compound claimed in Claim 1 of the ’117 patent. In ANDA litigation, infringement of a compound claim is frequently stipulated, shifting the focus to the patent's validity.
- Scope Questions: A potential dispute could arise over whether the specific form of dapagliflozin in the accused product (e.g., a particular salt or stereoisomer) falls within the scope of the claim language "pharmaceutically acceptable salt, a stereoisomer thereof, or a prodrug ester thereof."
V. Key Claim Terms for Construction
The complaint does not provide sufficient detail for analysis of claim construction issues. The primary asserted claim is a chemical structure claim, which typically presents fewer construction disputes than claims with functional or structural terms of degree.
VI. Other Allegations
Indirect Infringement
The complaint alleges that upon approval, Defendants will induce infringement of method claim 14 by encouraging physicians and patients to use the ANDA products in an infringing manner, specifically through the product's FDA-mandated labeling (Compl. ¶49). It further alleges contributory infringement on the basis that the ANDA products are a material part of the invention and are not staple articles of commerce suitable for substantial non-infringing use (Compl. ¶50).
Willful Infringement
The complaint does not use the term "willful," but it alleges that Defendants have actual knowledge of the ’117 patent as a result of providing the October 20, 2023 Notice Letter (Compl. ¶¶24, 45). In its prayer for relief, Plaintiff requests a declaration that the case is "exceptional" under 35 U.S.C. § 285, which provides a basis for recovering attorneys' fees, often in cases of willful or egregious conduct (Compl., Prayer for Relief ¶7).
VII. Analyst’s Conclusion: Key Questions for the Case
The resolution of this case will likely depend on the answers to a few central questions:
- Chemical Identity: Is the dapagliflozin compound that is the subject of Sun's ANDA the same as, or an equivalent of, the compound defined by Claim 1 of the ’117 patent? While this is the core infringement question, the answer may be straightforward if Sun seeks to market a bioequivalent product.
- Patent Validity: The central, albeit unstated, issue in the complaint is the anticipated defense of patent invalidity. The case will likely turn on whether Sun can prove by clear and convincing evidence that the asserted claims of the ’117 patent are invalid, for instance, on grounds of obviousness over the prior art or lack of adequate written description.
- Indirect Infringement: For the method of use claim (Claim 14), a key question will be whether the proposed label for Sun's generic product instructs or encourages physicians and patients to use the drug in a manner that directly infringes the patented method, thereby establishing the requisite intent for inducement.