Depomed Inc v. Strides Pharma Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Depomed, Inc. (California)
  • Defendant: Strides Pharma, Inc. (New Jersey) and Strides Pharma Global Pte Limited (Singapore)
  • Plaintiff’s Counsel: Robinson Miller LLC; McAndrews, Held & Malloy, Ltd.
• Case Identification: 2:17-cv-03180, D.N.J., 05/05/2017
• Venue Allegations: Venue is alleged based on Defendant Strides Pharma, Inc.’s corporate presence and business contacts within New Jersey, and on Strides Pharma Global Pte Limited’s alleged actions in concert with its U.S. affiliate and its intent to derive substantial revenue from the state.
• Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff’s ZIPSOR® (diclofenac potassium) capsules constitutes an act of patent infringement.
• Technical Context: The patents relate to methods of using specific low-dose, liquid-formulation versions of the non-steroidal anti-inflammatory drug (NSAID) diclofenac potassium for treating post-surgical acute pain.
• Key Procedural History: The complaint notes a prior lawsuit filed by Depomed in 2013 against Banner Pharmacaps and Watson Laboratories concerning a different ANDA for a generic ZIPSOR® product. That case involved five of the six patents asserted in the present action. The court in that prior case issued an opinion construing certain claim terms of U.S. Patent Nos. 7,662,858 and 7,884,095 before the litigation was terminated by a settlement agreement. The settlement permits Watson to launch its generic product on March 24, 2022.

Case Timeline

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

U.S. Patent No. 7,662,858 - Method of Treating Post-Surgical Acute Pain

The Invention Explained

• Problem Addressed: The patent describes a need for improved methods of treating post-surgical acute pain, particularly following outpatient procedures like a bunionectomy, that provide rapid pain relief without the risks associated with opioids or certain high-dose NSAIDs and COX-2 inhibitors (’858 Patent, col. 1:49-col. 2:12).
• The Patented Solution: The invention is a method of treatment using an orally administered low dose (between 13 and 25 mg) of diclofenac potassium formulated as a dispersible liquid, administered at regular intervals (every 4 to 8 hours) with a total daily dose not to exceed 100 mg (’858 Patent, col. 2:36-43). This specific formulation and dosing regimen is intended to provide rapid and effective analgesia for acute pain following bunionectomy surgery (’858 Patent, col. 2:23-31).
• Technical Importance: The method provides a non-opioid option for managing acute post-operative pain that aims to balance a rapid onset of action with a favorable safety profile, which is particularly relevant for outpatient surgeries (’858 Patent, col. 3:63-col. 4:8).

Key Claims at a Glance

• The complaint does not specify which claims are asserted but states its allegations against the patent generally (Compl. ¶¶27-30). Independent claim 1 is representative.
• Claim 1 Elements:
  • A method of treating acute post-bunionectomy pain in a patient.
  • Orally administering a dose of between about 13 to about 25 mg of diclofenac potassium.
  • The diclofenac potassium is in a dispersible liquid formulation.
  • Administering about every 4 hours to about 8 hours over a period of at least 24 hours.
  • The daily total amount of diclofenac potassium administered is less than or equal to about 100 mg.

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U.S. Patent No. 7,884,095 - Method of Treating Post-Surgical Acute Pain

The Invention Explained

• Problem Addressed: The patent addresses the same technical problem as the ’858 Patent: the need for effective, rapid-acting, non-opioid treatments for acute pain following outpatient surgery (’095 Patent, col. 1:50-col. 2:16).
• The Patented Solution: The ’095 Patent claims a method of treating acute post-osteotomy pain, a broader category of surgery that includes bunionectomy (’095 Patent, col. 29:10-18). The solution remains a specific low-dose regimen (13 to 25 mg) of diclofenac potassium in a dispersible liquid formulation, with the total daily dose capped at 100 mg (’095 Patent, Abstract). The patent explains that an osteotomy is a surgical procedure where a bone is cut to change its alignment, such as correcting a bone deformity (’095 Patent, col. 30:16-18).
• Technical Importance: This patent broadens the claimed method of use from the specific context of bunionectomy to the wider category of osteotomy, expanding the potential application of the low-dose liquid formulation for pain management.

Key Claims at a Glance

• The complaint does not specify which claims are asserted but states its allegations against the patent generally (Compl. ¶¶31-34). Independent claim 1 is representative.
• Claim 1 Elements:
  • A method of treating acute post-osteotomy pain in a patient.
  • Orally administering a dose of between about 13 to about 25 mg of diclofenac potassium.
  • The diclofenac potassium is in a dispersible liquid formulation.
  • Administering about every 4 hours to about 8 hours over a period of at least 24 hours.
  • The daily total amount of diclofenac potassium administered is less than or equal to about 100 mg.
  • Wherein the osteotomy is correction of a bone deformity.

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U.S. Patent No. 7,939,518 - Method of Treating Post-Surgical Acute Pain

• Technology Synopsis: This patent, part of the same family, is directed to a method of treating acute post-osteotomy pain. It claims a slightly different dosage range compared to the ’095 Patent (’518 Patent, Abstract).
• Asserted Claims: The complaint does not specify asserted claims (Compl. ¶¶35-38). Independent claim 1 recites a dose of "between about 13 to 30 mg" of diclofenac potassium.
• Accused Features: Defendants’ ANDA product, a 25 mg diclofenac potassium capsule, is accused of infringing this patent by seeking approval for a generic equivalent of ZIPSOR® (Compl. ¶¶6, 36).

U.S. Patent No. 8,110,606 - Method of Treating Post-Surgical Acute Pain

• Technology Synopsis: This patent is directed to a method of treating acute post-bunionectomy pain, similar to the ’858 Patent. It claims a dosage range of "between about 13 to 30 mg" of diclofenac potassium (’606 Patent, Abstract).
• Asserted Claims: The complaint does not specify asserted claims (Compl. ¶¶39-42). Independent claim 1 is directed to post-bunionectomy pain.
• Accused Features: Defendants’ ANDA product, a 25 mg diclofenac potassium capsule, is accused of infringing this patent (Compl. ¶¶6, 40).

U.S. Patent No. 8,623,920 - Method of Treating Post-Surgical Acute Pain

• Technology Synopsis: This patent claims a method of treating acute post-surgical pain defined as "moderately severe to severe" based on a specific score on a Numerical Pain Rating Scale (NPRS). The claimed dosage is "about 20 mg to 30 mg" and requires that the average Pain Intensity Difference (PID) over 48 hours is greater than 2 units (’920 Patent, col. 29:6-18). A certificate of correction was issued for this patent to correct a typographical error in dependent claim 12 (’920 Patent, Certificate of Correction).
• Asserted Claims: The complaint does not specify asserted claims (Compl. ¶¶43-46).
• Accused Features: Defendants’ ANDA product, a 25 mg diclofenac potassium capsule, is accused of infringing this patent (Compl. ¶¶6, 44).

U.S. Patent No. 9,561,200 - Method of Treating Post-Surgical Acute Pain

• Technology Synopsis: This patent is directed to a method for treating acute post-surgical pain that results from an osteotomy that includes internal fixation. The claimed dosage is "about 20 mg to about 30 mg" of diclofenac potassium (’200 Patent, col. 29:10-19).
• Asserted Claims: The complaint does not specify asserted claims (Compl. ¶¶47-50).
• Accused Features: Defendants’ ANDA product, a 25 mg diclofenac potassium capsule, is accused of infringing this patent (Compl. ¶¶6, 48).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Defendants' Abbreviated New Drug Application No. 210078 and the proposed drug product described therein: diclofenac potassium 25 mg oral capsules (Compl. ¶6).

Functionality and Market Context

The complaint alleges that Defendants’ product is a generic version of Depomed’s ZIPSOR® product (Compl. ¶6). ZIPSOR® is approved for the relief of mild to moderate acute pain (Compl. ¶18). By filing an ANDA, Defendants are representing that their proposed generic product is bioequivalent to ZIPSOR® and will have a label that recommends the same or similar methods of use. The complaint alleges that Defendants seek approval to commercially manufacture, use, and sell this product in the United States before the expiration of the patents-in-suit (Compl. ¶25).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not contain a claim chart or detailed, element-by-element infringement allegations for any of the asserted patents. The central infringement theory is statutory, based on 35 U.S.C. § 271(e)(2)(A), which defines the submission of an ANDA seeking approval to market a drug claimed in a patent before that patent’s expiration as an act of infringement (Compl. ¶28, 32, 36, 40, 44, 48).

The complaint alleges that Defendants' ANDA product is a "generic version of Depomed's ZIPSOR® product" (Compl. ¶6). This allegation implies that the proposed generic product contains the same active ingredient (diclofenac potassium) at the same dosage strength (25 mg) and is intended for the same therapeutic use (relief of acute pain) as the branded drug. The infringement allegation is therefore premised on the assertion that the method of use for which Defendants seek approval in their ANDA—and which will be described on the product's label—will fall within the scope of the asserted method claims of the patents-in-suit. The complaint does not provide sufficient detail for analysis of how specific features of the ANDA product or its proposed label meet specific claim limitations.

• Identified Points of Contention:
  • Scope Questions: A central question will be whether the method of administration described in the proposed label for Defendants’ ANDA product meets every limitation of the asserted method claims. This includes the specified indication (e.g., "post-bunionectomy pain"), dosage ("about 25 mg"), formulation type ("dispersible liquid"), and dosing frequency ("about every 4 to 8 hours").
  • Technical Questions: A potential point of dispute may be whether Defendants’ formulation qualifies as a "dispersible liquid formulation" as that term is used and defined in the patents-in-suit. The physical and chemical characteristics of the Defendants' formulation will be compared to the requirements of the claims as construed by the court.

V. Key Claim Terms for Construction

• The Term: "dispersible liquid formulation"

• Context and Importance: This term appears in the independent claims of all asserted patents (e.g., ’858 Patent, col. 29:8-9) and is central to the invention, which is not merely about using diclofenac, but using it in a specific type of formulation to achieve rapid pain relief. The dispute will likely focus on whether Defendants' generic formulation, contained within an oral capsule, meets the technical definition of this term as defined by the patent's intrinsic evidence. Practitioners may focus on this term because the prior Depomed v. Banner litigation involved construction of patent terms, suggesting this area has been contentious before (Compl. ¶21).

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification describes the formulation in general terms as "an oral dispersible liquid formulation comprising diclofenac potassium and at least one pharmaceutically acceptable, non-toxic dispersing agent" (’858 Patent, col. 3:60-64), which could suggest the term is not limited to a narrow list of excipients.
  • Evidence for a Narrower Interpretation: The specification provides detailed examples of formulations, including specific dispersing agents (e.g., PVP K-30), solubilizing agents (e.g., PEG 400), and surfactants (e.g., Polysorbate 80) (’858 Patent, col. 5:26-col. 6:67; Table 1). A defendant may argue that these specific embodiments limit the scope of the term to formulations with similar characteristics or components.

• The Term: "acute post-bunionectomy pain"

• Context and Importance: This term, found in the independent claims of the ’858 and ’606 patents, defines the specific patient population and medical indication for the claimed method. The infringement analysis will require determining whether the proposed label for Defendants' ANDA product specifically instructs, or inherently covers, the treatment of this type of pain. Its construction is critical for determining the scope of what constitutes an infringing use.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent background broadly discusses "post-surgical acute pain" and uses bunionectomy as a primary but not necessarily exclusive example of an outpatient surgery that results in such pain (’858 Patent, col. 1:45-51, col. 1:60-62).
  • Evidence for a Narrower Interpretation: The claim language itself is specific to "bunionectomy," and the patent's clinical trial data and detailed examples are focused on this particular surgery (’858 Patent, Example 2, col. 11:36-44). A defendant may argue that the term should be limited to pain resulting directly from that specific procedure, as opposed to general foot pain or pain from other osteotomies.

VI. Other Allegations

• Indirect Infringement: The complaint alleges future infringement under 35 U.S.C. § 271(b) and (c), which correspond to induced and contributory infringement (Compl. ¶29, 33, 37, 41, 45, 49). The factual basis for these allegations would be that Defendants, upon receiving FDA approval, will sell their product with a label and instructions that will inevitably lead medical professionals and patients to use the drug in a manner that directly infringes the patented methods.
• Willful Infringement: The complaint does not contain an explicit allegation of willful infringement. It requests that the case be declared "exceptional" under 35 U.S.C. § 285 to recover attorney fees, but does not plead the facts typically associated with a willfulness claim (Prayer for Relief ¶6).

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

• A core issue will be one of claim scope and construction: How will the court construe key terms like "dispersible liquid formulation," and will the construction from the prior Depomed v. Banner litigation be adopted in this case? The answer will determine whether the specific chemical and physical properties of Defendants' proposed generic product fall within the boundaries of the patent claims.
• A key evidentiary question will be one of label-based infringement: Does the proposed product label submitted with Defendants’ ANDA instruct a method of use that satisfies every element of at least one asserted claim? The case will likely turn on a comparison of the proposed label's instructions regarding indication, dosage, and frequency against the specific limitations recited in the patent claims.