Fennec Pharma Inc v. Cipla Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Fennec Pharmaceuticals Inc. (Canada/North Carolina)
  • Defendant: Cipla Limited (India) and Cipla USA, Inc. (Delaware/New Jersey)
  • Plaintiff's Counsel: Marino, Tortorella & Boyle, P.C.
• Case Identification: Fennec Pharmaceuticals Inc. v. Cipla Ltd., 2:23-cv-00123, D.N.J., 09/16/2024
• Venue Allegations: Venue is alleged to be proper based on Defendant Cipla USA, Inc. having a regular and established place of business in the District of New Jersey and Defendant Cipla Limited being a foreign corporation subject to personal jurisdiction within the district.
• Core Dispute: Plaintiff alleges that Defendants' filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff's PEDMARK® product constitutes infringement of two patents covering a pharmaceutical composition and its therapeutic use.
• Technical Context: The technology concerns a specific formulation of sodium thiosulfate used to reduce the risk of hearing loss (ototoxicity) associated with cisplatin-based chemotherapy in pediatric cancer patients.
• Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendants' submission of ANDA No. 218028 and associated Paragraph IV certifications. The certifications assert that Plaintiff's patents are invalid, unenforceable, or will not be infringed by the proposed generic product. This Third Amended Complaint adds allegations concerning the more recently issued of the two asserted patents. Plaintiff's PEDMARK® product is also noted to have FDA orphan-drug exclusivity until September 2029.

Case Timeline

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

II.A. U.S. Patent No. 11,617,793 - "Anhydrous Sodium Thiosulfate and Formulations Thereof"

The Invention Explained

• Problem Addressed: The patent addresses the problem of ototoxicity, or hearing loss, which is a significant and often permanent side effect of platinum-based chemotherapeutics like cisplatin, particularly in pediatric patients for whom normal hearing is critical for development U.S. Patent 11,617,793, col. 1:12-53
• The Patented Solution: The invention is a specific, stable pharmaceutical formulation of sodium thiosulfate intended to reduce ototoxicity U.S. Patent 11,617,793, abstract The formulation is defined by specific concentrations of sodium thiosulfate and boric acid, as well as a specific pH range, to provide a therapeutic composition suitable for administration U.S. Patent 11,617,793, col. 8:36-41
• Technical Importance: This formulation provides a specific, ready-to-administer solution designed to mitigate a debilitating side effect of a cornerstone cancer therapy without compromising the chemotherapy's effectiveness U.S. Patent 11,617,793, col. 1:47-53

Key Claims at a Glance

• The complaint asserts at least independent claim 1 Compl. ¶7
• Claim 1 of the '793 Patent recites the following essential elements:
  • A pharmaceutical composition
  • comprising sodium thiosulfate at a concentration of about 0.5 M
  • and further comprising about 0.004 M boric acid
  • wherein the pharmaceutical composition has a pH between about 6.5 and about 8.9 Compl. ¶42
• The complaint does not explicitly reserve the right to assert dependent claims.

II.B. U.S. Patent No. 11,964,018 - "Therapeutic Uses for Sodium Thiosulfate Formulations"

The Invention Explained

• Problem Addressed: The patent addresses the same problem as the '793 Patent: cisplatin-induced hearing loss in cancer patients, particularly children U.S. Patent 11,964,018, col. 1:26-58
• The Patented Solution: The invention is a method for reducing ototoxicity by administering the specific pharmaceutical formulation claimed in the '793 Patent to a patient receiving platinum-based chemotherapy U.S. Patent 11,964,018, abstract The patent protects the act of using the specific composition for its intended therapeutic purpose U.S. Patent 11,964,018, col. 8:36-48
• Technical Importance: This method patent provides legal protection for the specific, approved use of the formulation, complementing the patent on the composition itself and strengthening the intellectual property position around the therapy Compl. ¶11

Key Claims at a Glance

• The complaint asserts at least independent claim 1 Compl. ¶7
• Claim 1 of the '018 Patent recites the following essential elements:
  • A method of reducing ototoxicity in a human patient receiving a platinum based chemotherapeutic
  • comprising administering an effective amount of a pharmaceutical composition
  • wherein the composition comprises sodium thiosulfate at a concentration of about 0.5 M
  • and further comprises about 0.004 M boric acid
  • wherein the pharmaceutical composition has a pH between about 6.5 and about 8.9 Compl. ¶45
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

III.A. Product Identification

The accused instrumentality is "Cipla's ANDA Product," a generic sodium thiosulfate injection described in Abbreviated New Drug Application (ANDA) No. 218028 submitted to the FDA Compl. ¶13

III.B. Functionality and Market Context

• The complaint alleges that Cipla's ANDA Product is a generic version of Plaintiff's PEDMARK® product, intended for the same use: "reducing the risk of ototoxicity, induced by cisplatin chemotherapy in pediatric patients with localized, non-metastatic solid tumors" Compl. ¶13
• It is alleged that the Cipla ANDA Product will have a formulation containing "about 0.5 M sodium thiosulfate and about 0.004 M boric acid" with a pH between 7 and 9, thereby mirroring the formulation of PEDMARK® Compl. ¶50 Compl. ¶71
• The complaint alleges that Defendants intend to commercially manufacture, market, and sell the ANDA Product in the United States upon FDA approval, directly competing with PEDMARK® Compl. ¶15

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

IV.A. 11,617,793 Patent Infringement Allegations

IV.B. 11,964,018 Patent Infringement Allegations

IV.C. Identified Points of Contention

• Scope Questions: A central issue may be the construction of the term "about" as it applies to the concentrations of sodium thiosulfate and boric acid. The dispute may focus on whether the formulation detailed in Defendants' ANDA falls within the scope of "about 0.5 M" and "about 0.004 M" as construed by the court.
• Technical Questions: For the '793 Patent, an evidentiary question is whether the product Defendants seek to market will, in fact, have the chemical properties recited in claim 1. For the '018 Patent, the analysis will question whether the instructions for use in Defendants' proposed label will necessarily lead physicians and patients to practice all steps of the claimed method, and whether any substantial non-infringing uses for the product exist Compl. ¶78

V. Key Claim Terms for Construction

V.A. The Term

"about"

V.B. Context and Importance

This term appears in both asserted independent claims, qualifying the required molar concentrations of sodium thiosulfate ("about 0.5 M") and boric acid ("about 0.004 M") Compl. ¶42 Compl. ¶45 The construction of "about" is critical because it defines the permissible range of concentration variation. Its scope will determine whether Defendants' proposed formulation, if not precisely matching the recited values, still falls within the literal scope of the claims.

V.C. Intrinsic Evidence for Interpretation

• Evidence for a Broader Interpretation: Practitioners may cite the specification of the parent application to the '793 Patent, which explicitly defines the term. For example, the specification of U.S. Patent 11,291,728, a related family member, states that ""about" as used herein refers to any values... within a variation of up to +/-10% of the value modified by the term "about"" U.S. Patent 11,291,728, col. 5:29-33
• Evidence for a Narrower Interpretation: To argue for a more limited scope, practitioners may point to specific embodiments in the patent that disclose the exact concentrations. For instance, Example 8 and Table 13 in the '793 Patent describe an "Exemplary Sodium Thiosulfate Formulation" with exactly 0.5 M sodium thiosulfate and 0.004 M boric acid, which could suggest the inventors considered these precise values to be central to the invention U.S. Patent 11,617,793, col. 24

VI. Other Allegations

VI.A. Indirect Infringement

The complaint alleges both induced and contributory infringement for both patents Compl. ¶55 Compl. ¶56 Compl. ¶57 Inducement is primarily based on the allegation that Defendants' proposed product label will instruct and encourage physicians and patients to administer the drug in a manner that directly infringes the asserted method claim ('018 Patent) and composition claim ('793 Patent) Compl. ¶55 Compl. ¶76 Contributory infringement is based on the allegation that the accused product is not a staple article of commerce and has no substantial non-infringing uses Compl. ¶57 Compl. ¶78

VI.B. Willful Infringement

The complaint alleges that Defendants have actual knowledge of the '793 and '018 Patents, citing the Paragraph IV notice letters received by Plaintiff Compl. ¶49 Compl. ¶70 It further alleges that Defendants' positions on invalidity and non-infringement are "devoid of an objective good faith basis," which forms the basis for seeking enhanced damages and attorneys' fees for an "exceptional case" Compl. ¶65 Compl. ¶86

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

• A core issue will be one of definitional scope: How will the court construe the term "about" as it modifies the claimed concentrations? The explicit definition of "+/- 10%" in the specification of a related patent provides a strong starting point, and the case may turn on whether Defendants' proposed generic formulation falls inside or outside of this range.
• A key evidentiary question will be one of infringing use: For the method-of-use patent ('018 Patent), the central issue is whether Defendants' proposed product label will inevitably induce infringement by medical professionals. The analysis will focus on whether the label's instructions for the FDA-approved indication align with the steps of the asserted claim and whether any commercially significant, non-infringing uses exist.